NOVEL ANTI-CD276 ANTIBODIES AND THE USES THEREOF

Abstract
Provided are anti-CD276 antibodies, and anti-CD276/PD-L1 bispecific antibody molecules, isolated polynucleotides encoding the same, pharmaceutical compositions comprising the same, and the uses thereof.
Description
FIELD OF THE INVENTION

The present disclosure generally relates to novel anti-CD276 antibodies.


BACKGROUND

B7-H3 (CD276, UniProt IDs for human amino acid sequence: Q5ZPR3 and mouse amino acid sequence: Q8VE98) is an important newly found immune checkpoint member of the B7 and CD28 families, which is a type I transmembrane costimulatory molecule, existing in two isoforms determined by its extracellular domain. In mice, the extracellular domain consists of a single pair of immunoglobulin variable (IgV)-like and immunoglobulin constant (IgC)-like domains, whereas in humans it consists of one pair (21 g-B7-H3) or two identical pairs (4Ig-B7-H3) due to exon duplication. B7-H3 mRNA is widely distributed in most tissues; in contrast, B7-H3 protein has a very limited expression on normal tissues because of its post-transcriptional regulation by microRNAs. However, B7-H3 protein is expressed at high frequency on many different cancer types (60% of all cancers) (“B7-H3: an attractive target for antibody-based immunotherapy”. Clinical Cancer Research: clincanres.2584.2020).


The function of B7-H3 has been controversial. It was classified as either a costimulatory molecule for T cell activation that inhibits tumor antigen-specific immune responses, or the non-immunological role such as promoting migration, tumor growth, invasion, metastasis, malignant stage, recurrence rate, angiogenesis, chemoresistance, epithelial-to-mesenchymal transition, and affecting tumor cell metabolism. The receptor for B7-H3 has been reported to be triggering receptor expressed on myeloid cell (TREM)-like transcript 2 (TLT-2, or TREML2), which binds B7-H3 and costimulates activation of CD8 T cells in particular. B7-H3 is also reported an inhibitor for NK cells and osteoblastic cells by ligating unknown receptor(s). (The contrasting role of B7-H3, PNAS Jul. 29, 2008, 105 (30) 10277-10278). Treatment with monoclonal antibodies to block B7-H3 are the main immunotherapeutic strategies for cancer treatment.


Based on the clinical success of inhibitory immune checkpoint blockade (CTLA-4, PD-1, and PD-L1), mAbs against CD276 appear to be a promising therapeutic strategy worthy of development. Due to its selective expression on solid tumors, several groups have generated anti-CD276 antibodies, such as enoblituzumab (MGA271), omburtamab, MGD009, MGC018, DS-7300a, and CAR T cells (“B7-H3: an attractive target for antibody-based immunotherapy”. Clinical Cancer Research: clincanres.2584.2020), and observed tumor growth suppression in vitro and in vivo. CD276 is also reported to be expressed in hematological tumor cells (see Wei Zhang et al., B7 Family Members in Lymphoma: Promising Novel Targets for Tumor Immunotherapy? Front. Oncol., 31 Mar. 2021), indicating that CD276 can also be a potential target for treating hematological cancers.


Despite of the development of therapeutics targeting the CD276, there is a significant need for novel anti-CD276 antibodies.


BRIEF SUMMARY OF THE INVENTION

Throughout the present disclosure, the articles “a,” “an,” and “the” are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, “an antibody” means one antibody or more than one antibody.


The present disclosure provides novel anti-CD276 antibody molecules, amino acid and nucleotide sequences thereof, and uses thereof.


In one aspect, the present disclosure provides an isolated antibody or an antigen-binding fragment thereof, comprising 1, 2, or 3 heavy chain complementarity determining region (CDR) sequences selected from the group consisting of: SEQ ID NOs: 1-3, 9-11, 17-19, 25-27, 33-35, 41-43, 49-51, 57-59, 65-67, 73-75, 81-83, 89-91, 97-99, 105-107, 113-115, 121-123, 129-131, 137-139, 145-147, 153-155, 161-163, 169-171, 177-179, 185-187, 193-195, 201-203, 209-211, 217-219, 225-227, 233-235, 241-243, 249-251, 257-259, 265-267, 273-275, 281-283, 289-291, 297-299, 305-307, 313-315, 321-323, 329-331, 337-339 and 374-375, and/or 1, 2, or 3 light chain CDR sequences selected from the group consisting of: SEQ ID NOs: 4-6, 12-14, 20-22, 28-30, 36-38, 44-46, 52-54, 60-62, 68-70, 76-78, 84-86, 92-94, 100-102, 108-110, 116-118, 124-126, 132-134, 140-142, 148-150, 156-158, 164-166, 172-174, 180-181, 188-190, 196-198, 204-206, 212-214, 220-222, 228-230, 236-238, 244-246, 252-254, 260-262, 268-270, 276-278, 284-286, 292-294, 300-302, 308-310, 316-318, 324-326, 332-334, 340-342 and 376-377.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein comprises a heavy chain variable region selected from the group consisting of:

    • a) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 1-3;
    • b) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 9-11;
    • c) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 17-19;
    • d) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 25-27;
    • e) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 33-35;
    • f) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 41-43;
    • g) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 49-51;
    • h) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 57-59;
    • i) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 65-67;
    • j) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 73-75;
    • k) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 81-83;
    • l) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 89-91;
    • m) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 97-99;
    • n) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 105-107;
    • o) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 113-115;
    • p) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 121-123;
    • q) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 129-131;
    • r) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 137-139;
    • s) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 145-147;
    • t) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 153-155;
    • u) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 161-163;
    • v) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 169-171;
    • w) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 177-179;
    • x) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 185-187;
    • y) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 193-195;
    • z) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 201-203;
    • aa) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 209-211;
    • bb) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 217-219;
    • cc) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 225-227;
    • dd) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 233-235;
    • ee) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 241-243;
    • ff) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 249-251;
    • gg) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 257-259;
    • hh) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 265-267;
    • ii) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 273-275;
    • jj) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 281-283;
    • kk) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 289-291;
    • ll) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 297-299;
    • mm) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 305-307;
    • nn) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 313-315;
    • oo) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 321-323;
    • pp) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 329-331;
    • qq) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 337-339; and
    • rr) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 9, 374 and 375.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein comprises a light chain variable region selected from the group consisting of:

    • a) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 4-6;
    • b) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 12-14;
    • c) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 20-22;
    • d) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 28-30;
    • e) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 36-38;
    • f) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 44-46;
    • g) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 52-54;
    • h) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 60-62;
    • i) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 68-70;
    • j) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 76-78;
    • k) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 84-86;
    • l) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 92-94;
    • m) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 100-102, 108-110;
    • n) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 108-110;
    • o) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 116-118;
    • p) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 124-126;
    • q) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 132-134;
    • r) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 140-142;
    • s) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 148-150;
    • t) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 156-158;
    • u) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 164-166;
    • v) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 172-174;
    • w) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 180-181;
    • x) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 188-190;
    • y) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 196-198;
    • z) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 204-206;
    • aa) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 212-214;
    • bb) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 220-222;
    • cc) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 228-230;
    • dd) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 236-238;
    • ee) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 244-246;
    • ff) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 252-254;
    • gg) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 260-262;
    • hh) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 268-270;
    • ii) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 276-278;
    • jj) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 284-286;
    • kk) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 292-294;
    • ll) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 300-302;
    • mm) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 308-310;
    • nn) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 316-318;
    • oo) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 324-326;
    • pp) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 332-334;
    • qq) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 340-342;
    • rr) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 376, 13 and 14; and
    • ss) a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NOs: 377, 45 and 46.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein comprises:

    • a) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 1, SEQ ID NO: 2, and SEQ ID NO: 3; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 4, SEQ ID NO: 5, and SEQ ID NO: 6;
    • b) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14;
    • c) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 17, SEQ ID NO: 18, and SEQ ID NO: 19; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 20, SEQ ID NO: 21 and SEQ ID NO: 22;
    • d) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 25, SEQ ID NO: 26, and SEQ ID NO: 27; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 28, SEQ ID NO: 29, and SEQ ID NO: 30;
    • e) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 33, SEQ ID NO: 34, and SEQ ID NO: 35; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 36, SEQ ID NO: 37, and SEQ ID NO: 38;
    • f) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:41, SEQ ID NO: 42, and SEQ ID NO: 43; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO:46;
    • g) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:49, SEQ ID NO: 50, and SEQ ID NO: 51; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 52, SEQ ID NO: 53, and SEQ ID NO: 54;
    • h) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 57, SEQ ID NO: 58, and SEQ ID NO: 59; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 60, SEQ ID NO: 61, and SEQ ID NO: 62;
    • i) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 65, SEQ ID NO: 66, and SEQ ID NO: 67; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 68, SEQ ID NO: 69, and SEQ ID NO: 70;
    • j) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 73, SEQ ID NO: 74, and SEQ ID NO: 75; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 76, SEQ ID NO: 77, and SEQ ID NO: 78;
    • k) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 81, SEQ ID NO: 82, and SEQ ID NO: 83; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 84, SEQ ID NO: 85, and SEQ ID NO: 86;
    • l) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 89, SEQ ID NO: 90, and SEQ ID NO: 91; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 92, SEQ ID NO: 93, and SEQ ID NO: 94;
    • m) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 97, SEQ ID NO: 98, and SEQ ID NO: 99; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 100, SEQ ID NO: 101, and SEQ ID NO: 102;
    • n) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 105, SEQ ID NO: 106, and SEQ ID NO: 107; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 108, SEQ ID NO: 109 and SEQ ID NO: 110;
    • o) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 113, SEQ ID NO: 114, and SEQ ID NO: 115; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 116, SEQ ID NO: 117, and SEQ ID NO: 118;
    • p) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 121, SEQ ID NO: 122, and SEQ ID NO: 123; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 124, SEQ ID NO: 125, and SEQ ID NO: 126;
    • q) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:129, SEQ ID NO: 130, and SEQ ID NO: 131; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 132, SEQ ID NO: 133, and SEQ ID NO:134;
    • r) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:137, SEQ ID NO: 138, and SEQ ID NO: 139; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 140, SEQ ID NO: 141, and SEQ ID NO: 142;
    • s) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 145, SEQ ID NO: 146, and SEQ ID NO: 147; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 148, SEQ ID NO: 149, and SEQ ID NO: 150;
    • t) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 153, SEQ ID NO: 154, and SEQ ID NO: 155; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 156, SEQ ID NO: 157, and SEQ ID NO: 158;
    • u) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 161, SEQ ID NO: 162, and SEQ ID NO: 163; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 164, SEQ ID NO: 165, and SEQ ID NO: 166;
    • v) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 169, SEQ ID NO: 170, and SEQ ID NO: 171; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 172, SEQ ID NO: 173, and SEQ ID NO: 174;
    • w) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 177, SEQ ID NO: 178, and SEQ ID NO: 179; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 180, SEQ ID NO: 181, and SEQ ID NO: 182;
    • x) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 185, SEQ ID NO: 186, and SEQ ID NO: 187; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 188, SEQ ID NO: 189, and SEQ ID NO: 190;
    • y) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 193, SEQ ID NO: 194, and SEQ ID NO: 195; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 196, SEQ ID NO: 197 and SEQ ID NO: 198;
    • z) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 201, SEQ ID NO: 202, and SEQ ID NO: 203; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 204, SEQ ID NO: 205, and SEQ ID NO: 206;
    • aa) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 209, SEQ ID NO: 210, and SEQ ID NO: 211; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 212, SEQ ID NO: 213, and SEQ ID NO: 214;
    • bb) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:217, SEQ ID NO: 218, and SEQ ID NO: 219; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 220, SEQ ID NO: 221, and SEQ ID NO:222;
    • cc) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:225, SEQ ID NO: 226, and SEQ ID NO: 227; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 228, SEQ ID NO: 229, and SEQ ID NO: 230;
    • dd) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 233, SEQ ID NO: 234, and SEQ ID NO: 235; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 236, SEQ ID NO: 237, and SEQ ID NO: 238;
    • ee) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 241, SEQ ID NO: 242, and SEQ ID NO: 243; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 244, SEQ ID NO: 245, and SEQ ID NO: 246;
    • ff) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 249, SEQ ID NO: 250, and SEQ ID NO: 251; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 252, SEQ ID NO: 253, and SEQ ID NO: 254;
    • gg) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 257, SEQ ID NO: 258, and SEQ ID NO: 259; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 260, SEQ ID NO: 261, and SEQ ID NO: 262;
    • hh) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 265, SEQ ID NO: 266, and SEQ ID NO: 267; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 268, SEQ ID NO: 269, and SEQ ID NO: 270;
    • ii) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 273, SEQ ID NO: 274, and SEQ ID NO: 275; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 276, SEQ ID NO: 277, and SEQ ID NO: 278;
    • jj) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 281, SEQ ID NO: 282, and SEQ ID NO: 283; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 284, SEQ ID NO: 285 and SEQ ID NO: 286;
    • kk) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 289, SEQ ID NO: 290, and SEQ ID NO: 291; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 292, SEQ ID NO: 293, and SEQ ID NO: 294;
    • ll) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 297, SEQ ID NO: 298, and SEQ ID NO: 299; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 300, SEQ ID NO: 301, and SEQ ID NO: 302;
    • mm) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:305, SEQ ID NO: 306, and SEQ ID NO: 307; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 308, SEQ ID NO: 309, and SEQ ID NO:310;
    • nn) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:313, SEQ ID NO: 314, and SEQ ID NO: 315; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 316, SEQ ID NO: 317, and SEQ ID NO: 318;
    • oo) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 321, SEQ ID NO: 322, and SEQ ID NO: 323; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 324, SEQ ID NO: 325, and SEQ ID NO: 326;
    • pp) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 329, SEQ ID NO: 330, and SEQ ID NO: 331; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 332, SEQ ID NO: 333, and SEQ ID NO: 334;
    • qq) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 337, SEQ ID NO: 338, and SEQ ID NO: 339; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 340, SEQ ID NO: 341, and SEQ ID NO: 342; or
    • rr) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 9, SEQ ID NO: 374, and SEQ ID NO: 375; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 376, SEQ ID NO: 13, and SEQ ID NO: 14; or
    • ss) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 41, SEQ ID NO: 42, and SEQ ID NO: 43; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 377, SEQ ID NO: 45, and SEQ ID NO: 46.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein comprises a heavy chain variable region selected from the group consisting of: SEQ ID NO: 7, SEQ ID NO: 15, SEQ ID NO: 23, SEQ ID NO: 31, SEQ ID NO: 39, SEQ ID NO: 47, SEQ ID NO: 55, SEQ ID NO: 63, SEQ ID NO: 71, SEQ ID NO: 79, SEQ ID NO: 87, SEQ ID NO: 95, SEQ ID NO: 103, SEQ ID NO: 111, SEQ ID NO: 119, SEQ ID NO: 127, SEQ ID NO: 135, SEQ ID NO: 143, SEQ ID NO: 151, SEQ ID NO: 159, SEQ ID NO: 167, SEQ ID NO: 175, SEQ ID NO: 183, SEQ ID NO: 191, SEQ ID NO: 199, SEQ ID NO: 207, SEQ ID NO: 215, SEQ ID NO: 223, SEQ ID NO: 231, SEQ ID NO: 239, SEQ ID NO: 247, SEQ ID NO: 255, SEQ ID NO: 263, SEQ ID NO: 271, SEQ ID NO: 279, SEQ ID NO: 287, SEQ ID NO: 295, SEQ ID NO: 303, SEQ ID NO: 311, SEQ ID NO: 319, SEQ ID NO: 327, SEQ ID NO: 335, SEQ ID NO: 343, SEQ ID NO: 347, and SEQ ID NO: 349 and the homologue sequences of at least 80% (e.g., at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%) sequence identity thereof.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein comprises a light chain variable region selected from the group consisting of: SEQ ID NO: 8, SEQ ID NO: 16, SEQ ID NO: 24, SEQ ID NO: 32, SEQ ID NO: 40, SEQ ID NO: 48, SEQ ID NO: 56, SEQ ID NO: 64, SEQ ID NO: 72, SEQ ID NO: 80, SEQ ID NO: 88, SEQ ID NO: 96, SEQ ID NO: 104, SEQ ID NO: 112, SEQ ID NO: 120, SEQ ID NO: 128, SEQ ID NO: 136, SEQ ID NO: 144, SEQ ID NO: 152, SEQ ID NO: 160, SEQ ID NO: 168, SEQ ID NO: 1756, SEQ ID NO: 184, SEQ ID NO: 192, SEQ ID NO: 200, SEQ ID NO: 208, SEQ ID NO: 216, SEQ ID NO: 224, SEQ ID NO: 232, SEQ ID NO: 240, SEQ ID NO: 248, SEQ ID NO: 256, SEQ ID NO: 264, SEQ ID NO: 272, SEQ ID NO: 280, SEQ ID NO: 288, SEQ ID NO: 296, SEQ ID NO: 304, SEQ ID NO: 312, SEQ ID NO: 320, SEQ ID NO: 328, SEQ ID NO: 336, SEQ ID NO: 344, SEQ ID NO: 348, and SEQ ID NO: 350 and the homologue sequences of at least 80% (e.g., at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%) sequence identity thereof.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein comprises:

    • a) a heavy chain variable region comprising SEQ ID NO: 7 and a light chain variable region comprising SEQ ID NO: 8;
    • b) a heavy chain variable region comprising SEQ ID NO: 15 and a light chain variable region comprising SEQ ID NO: 16;
    • c) a heavy chain variable region comprising SEQ ID NO: 23 and a light chain variable region comprising SEQ ID NO: 24;
    • d) a heavy chain variable region comprising SEQ ID NO: 31 and a light chain variable region comprising SEQ ID NO: 32;
    • e) a heavy chain variable region comprising SEQ ID NO: 39 and a light chain variable region comprising SEQ ID NO: 40;
    • f) a heavy chain variable region comprising SEQ ID NO: 47 and a light chain variable region comprising SEQ ID NO: 48;
    • g) a heavy chain variable region comprising SEQ ID NO: 55 and a light chain variable region comprising SEQ ID NO: 56;
    • h) a heavy chain variable region comprising SEQ ID NO: 63 and a light chain variable region comprising SEQ ID NO: 64;
    • i) a heavy chain variable region comprising SEQ ID NO: 71 and a light chain variable region comprising SEQ ID NO: 72;
    • j) a heavy chain variable region comprising SEQ ID NO: 79 and a light chain variable region comprising SEQ ID NO: 80;
    • k) a heavy chain variable region comprising SEQ ID NO: 87 and a light chain variable region comprising SEQ ID NO: 88;
    • l) a heavy chain variable region comprising SEQ ID NO: 95 and a light chain variable region comprising SEQ ID NO: 96;
    • m) a heavy chain variable region comprising SEQ ID NO: 103 and a light chain variable region comprising SEQ ID NO: 104;
    • n) a heavy chain variable region comprising SEQ ID NO: 111 and a light chain variable region comprising SEQ ID NO: 112;
    • o) a heavy chain variable region comprising SEQ ID NO: 119 and a light chain variable region comprising SEQ ID NO: 120;
    • p) a heavy chain variable region comprising SEQ ID NO: 127 and a light chain variable region comprising SEQ ID NO: 128;
    • q) a heavy chain variable region comprising SEQ ID NO: 135 and a light chain variable region comprising SEQ ID NO: 136;
    • r) a heavy chain variable region comprising SEQ ID NO: 143 and a light chain variable region comprising SEQ ID NO: 144;
    • s) a heavy chain variable region comprising SEQ ID NO: 151 and a light chain variable region comprising SEQ ID NO: 152;
    • t) a heavy chain variable region comprising SEQ ID NO: 159 and a light chain variable region comprising SEQ ID NO: 160;
    • u) a heavy chain variable region comprising SEQ ID NO: 167 and a light chain variable region comprising SEQ ID NO: 168;
    • v) a heavy chain variable region comprising SEQ ID NO: 175 and a light chain variable region comprising SEQ ID NO: 176;
    • w) a heavy chain variable region comprising SEQ ID NO: 183 and a light chain variable region comprising SEQ ID NO: 184;
    • x) a heavy chain variable region comprising SEQ ID NO: 191 and a light chain variable region comprising SEQ ID NO: 192;
    • y) a heavy chain variable region comprising SEQ ID NO: 199 and a light chain variable region comprising SEQ ID NO: 200;
    • z) a heavy chain variable region comprising SEQ ID NO: 207 and a light chain variable region comprising SEQ ID NO: 208;
    • aa) a heavy chain variable region comprising SEQ ID NO: 215 and a light chain variable region comprising SEQ ID NO: 216;
    • bb) a heavy chain variable region comprising SEQ ID NO: 223 and a light chain variable region comprising SEQ ID NO: 224;
    • cc) a heavy chain variable region comprising SEQ ID NO: 231 and a light chain variable region comprising SEQ ID NO: 232;
    • dd) a heavy chain variable region comprising SEQ ID NO: 239 and a light chain variable region comprising SEQ ID NO: 240;
    • ee) a heavy chain variable region comprising SEQ ID NO: 247 and a light chain variable region comprising SEQ ID NO: 248;
    • ff) a heavy chain variable region comprising SEQ ID NO: 255 and a light chain variable region comprising SEQ ID NO: 256;
    • gg) a heavy chain variable region comprising SEQ ID NO: 263 and a light chain variable region comprising SEQ ID NO: 264;
    • hh) a heavy chain variable region comprising SEQ ID NO: 271 and a light chain variable region comprising SEQ ID NO: 272;
    • ii) a heavy chain variable region comprising SEQ ID NO: 279 and a light chain variable region comprising SEQ ID NO: 280;
    • jj) a heavy chain variable region comprising SEQ ID NO: 287 and a light chain variable region comprising SEQ ID NO: 288;
    • kk) a heavy chain variable region comprising SEQ ID NO: 295 and a light chain variable region comprising SEQ ID NO: 296;
    • ll) a heavy chain variable region comprising SEQ ID NO: 303 and a light chain variable region comprising SEQ ID NO: 304;
    • mm) a heavy chain variable region comprising SEQ ID NO: 311 and a light chain variable region comprising SEQ ID NO: 312;
    • nn) a heavy chain variable region comprising SEQ ID NO: 319 and a light chain variable region comprising SEQ ID NO: 320;
    • oo) a heavy chain variable region comprising SEQ ID NO: 327 and a light chain variable region comprising SEQ ID NO: 328;
    • pp) a heavy chain variable region comprising SEQ ID NO: 335 and a light chain variable region comprising SEQ ID NO:336;
    • qq) a heavy chain variable region comprising SEQ ID NO: 343 and a light chain variable region comprising SEQ ID NO: 344;
    • rr) a heavy chain variable region comprising SEQ ID NO: 347 and a light chain variable region comprising SEQ ID NO: 348; or
    • ss) a heavy chain variable region comprising SEQ ID NO: 349 and a light chain variable region comprising SEQ ID NO: 350.


In some embodiments, the antibody or antigen-binding fragment thereof is humanized.


In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable region comprising SEQ ID NO: 378 (EVOLVESGGGLXQPGXSLRLSCXTSGFTLSDYYMSWVRQXPGKGLEWVXF MRNKANXYTTEYSASVRGRFTISRDTSKSXIYLQMNSLXXEDTAVYYCVRDR XGRPFAYWGQGTLVTVSS), wherein the X at position i (i=12, 16, 23, 40, 49, 57, 80, 89, 90 and 103) of SEQ ID NO: 378 is referred as XHi, wherein XH12 is V or I, XH16 is G or R, XH23 is A or T, XH40 is A or P, XH49 is G or S, XH57 is A or G, XH80 is I or T, XH89 is R or K, XH90 is A or T, XH103 is D or E; and a light chain variable region comprising SEQ ID NO: 379 (DIXMTQSPXSLXXXXGXXXXIXCKSSQSLLNXINQKNFLTWYXQKPGXXPX LLIYWASTRESGVPXRFSGSGSGTDFTLXISXXXXEDLXXYYCQNDYTYPLTF GQGTKLEIK), wherein the X at position i (i=3, 9, 12, 13, 14, 15, 17, 18, 19, 20, 22, 32, 43, 48, 49, 51, 66, 80, 83, 84, 85, 86, 90 and 91) of SEQ ID NO: 379 is referred as XLi, wherein XL3 is V or Q, XL9 is D, L or S, XL12 is A, S or P, XL13 is A or V, XL14 is S or T, XL15 is L, V or P, XL17 is D or E, XL18 is R or P, XL19 is A or V, XL20 is S or T, XL22 is N, T or S, XL32 is A or S, XL43 is Q or L, XL48 is Q or K, XL49 is A, P or S, XL51 is K or Q, XL66 is S or D, XL80 is K or T, XL83 is R or S, XL84 is L or V, XL85 is Q or E, XL86 is A or P, XL90 is A or G, XL91 is T or V.


In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable region comprising SEQ ID NO: 380 (QVQLQESGPGLVKPSXTLSLTCXVXGYSITSDYAWNWIRQXPGKGLEWIGYI SHSGSTSYNPSLKSRVTISRDTSKNQFSLKLSSVTAADTAVYYCARSLGRRWY FDVWGQGTTVTVSS), wherein the X at position i (i=16, 23, 25 and 41) of SEQ ID NO: 380 is referred as XHi, wherein XH16 is E or Q, XH23 is A or T, XH25 is S or Y, XH41 is H or P; and a light chain variable region comprising SEQ ID NO: 381 (DIXMTQSPXSLXXXXGXXXXIXCKSSQSLLXSSTQKNYLAWYXQKPGXXPX LLIYFASTRDSGVPXRFSGSGSGTDFTLXISXXXXEDLXXYFCQQHYIIPFTFG QGTKLEIK), wherein the X at position i (i=3, 9, 12, 13, 14, 15, 17, 18, 19, 20, 22, 31, 43, 48, 49, 51, 66, 80, 83, 84, 85, 86, 90 and 91) of SEQ ID NO: 381 is referred as XLi, wherein XL3 is V or Q, XL9 is D, L or S, XL12 is A, S or P, XL13 is A or V, XL14 IS S or T, XL15 is L, V or P, XL17 is D or E, XL18 is R or P, XL19 is A or V, XL20 is S or T, XL22 is N, T or S, XL31 is N or Q, XL43 is Q or L, XL48 is Q or K, XL49 is A, P or S, XL51 is K or Q, XL66 is S or D, XL80 is K or T, XL83 is R or S, XL84 is L or V, XL85 is Q or E, XL86 is A or P, XL90 is A or G, XL91 is T or V.


In some embodiments, the antibody or antigen-binding fragment thereof comprises:

    • (i) a heavy chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 9, SEQ ID NO: 10 or 374 (MRNKANAYTT), and SEQ ID NO: 11 or 375 (VRDREGRPFAY), respectively; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 12 or 376 (QSLLNAINQKNF), SEQ ID NO: 13, and SEQ ID NO: 14, respectively; or
    • (ii) a heavy chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 41, SEQ ID NO: 42, and SEQ ID NO: 43, respectively; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 44 or 377 (QSLLQSSTQKNY), SEQ ID NO: 45, and SEQ ID NO: 46, respectively.


In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable region comprising a sequence selected from SEQ ID NO: 351, 353, 355, 357, 358, 360, 362, 364, 365, 367 and 370; and a light chain variable region comprising a sequence selected from SEQ ID NO: 352, 354, 356, 359, 361, 363, 366, 368, 369, 371, 372 and 373.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein comprises:

    • a) a heavy chain variable region comprising SEQ ID NO: 351 and a light chain variable region comprising SEQ ID NO: 352;
    • b) a heavy chain variable region comprising SEQ ID NO: 353 and a light chain variable region comprising SEQ ID NO: 354;
    • c) a heavy chain variable region comprising SEQ ID NO: 355 and a light chain variable region comprising SEQ ID NO: 352;
    • d) a heavy chain variable region comprising SEQ ID NO: 355 and a light chain variable region comprising SEQ ID NO: 356;
    • e) a heavy chain variable region comprising SEQ ID NO: 357 and a light chain variable region comprising SEQ ID NO: 352;
    • f) a heavy chain variable region comprising SEQ ID NO: 357 and a light chain variable region comprising SEQ ID NO: 354;
    • g) a heavy chain variable region comprising SEQ ID NO: 358 and a light chain variable region comprising SEQ ID NO: 359;
    • h) a heavy chain variable region comprising SEQ ID NO: 360 and a light chain variable region comprising SEQ ID NO: 361;
    • i) a heavy chain variable region comprising SEQ ID NO: 362 and a light chain variable region comprising SEQ ID NO: 359;
    • j) a heavy chain variable region comprising SEQ ID NO: 362 and a light chain variable region comprising SEQ ID NO: 363;
    • k) a heavy chain variable region comprising SEQ ID NO: 364 and a light chain variable region comprising SEQ ID NO: 359;
    • l) a heavy chain variable region comprising SEQ ID NO: 364 and a light chain variable region comprising SEQ ID NO: 361;
    • m) a heavy chain variable region comprising SEQ ID NO: 365 and a light chain variable region comprising SEQ ID NO: 366;
    • n) a heavy chain variable region comprising SEQ ID NO: 367 and a light chain variable region comprising SEQ ID NO: 368;
    • o) a heavy chain variable region comprising SEQ ID NO: 367 and a light chain variable region comprising SEQ ID NO: 369;
    • p) a heavy chain variable region comprising SEQ ID NO: 367 and a light chain variable region comprising SEQ ID NO: 366;
    • q) a heavy chain variable region comprising SEQ ID NO: 370 and a light chain variable region comprising SEQ ID NO: 369;
    • r) a heavy chain variable region comprising SEQ ID NO: 370 and a light chain variable region comprising SEQ ID NO: 366;
    • s) a heavy chain variable region comprising SEQ ID NO: 365 and a light chain variable region comprising SEQ ID NO: 371;
    • t) a heavy chain variable region comprising SEQ ID NO: 367 and a light chain variable region comprising SEQ ID NO: 372;
    • u) a heavy chain variable region comprising SEQ ID NO: 367 and a light chain variable region comprising SEQ ID NO: 373;
    • v) a heavy chain variable region comprising SEQ ID NO: 367 and a light chain variable region comprising SEQ ID NO: 371;
    • w) a heavy chain variable region comprising SEQ ID NO: 370 and a light chain variable region comprising SEQ ID NO: 373; or
    • x) a heavy chain variable region comprising SEQ ID NO: 370 and a light chain variable region comprising SEQ ID NO: 371.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein further comprises one or more amino acid residue substitutions or modifications yet retains specific binding affinity to human CD276.


In some embodiments, the substitution is in one or more CDR sequences, and/or in one or more of the VH or VL sequences but not in any of the CDR sequences.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein further comprises an immunoglobulin constant region, optionally a constant region of human Ig, or optionally a constant region of human IgG.


In some embodiments, the constant region comprises a constant region of human IgG1, IgG2, IgG3, or IgG4.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein is a chimeric or humanized.


In some embodiments, the antibody or antigen-binding fragment thereof provided herein is a Fab, a Fab′, a F(ab′)2, a Fd, an Fv fragment, a disulfide stabilized Fv fragment (dsFv), a (dsFv)2, a single-chain antibody molecule (scFv), a camelized single domain antibody, a nanobody, a domain antibody, and a bivalent domain antibody.


In some embodiments, the antibody or antigen-binding fragment is linked to one or more conjugates. In some embodiments, the conjugate is covalently attached either directly or via a linker. In some embodiments, the conjugate comprises a clearance-modifying agent, a chemotherapeutic agent, a toxin, a radioactive isotope, a lanthanide, a luminescent label, a fluorescent label, an enzyme-substrate label, a DNA-alkylators, a topoisomerase inhibitor, a tubulin-binders, or other anticancer drugs.


In some embodiments, the antibody or antigen-binding fragment is capable of specifically binding to CD276. In some embodiments, the CD276 are derived from human. In some embodiments, the CD276 is a recombinant CD276 or a CD276 expressed on a cell surface.


In one aspect, the present disclosure provides an antibody or antigen-binding fragment thereof, which competes for the same epitope with the antibody or antigen-binding fragment thereof provided herein.


In one aspect, the present disclosure provides a pharmaceutical composition comprising the antibody or antigen-binding fragment thereof provided herein, and a pharmaceutically acceptable carrier.


In some embodiments, the pharmaceutical composition provided herein further comprises a second therapeutic agent.


In some embodiments, the second therapeutic agent is an antagonist against one or more immunoinhibitory molecules.


In some embodiments, the second therapeutic agent is a PD-L1 antagonist.


In some embodiments, the PD-L1 antagonist is a PD-L1 antibody or antigen-binding fragment thereof.


In one aspect, the present disclosure provides an isolated polynucleotide encoding the antibody or antigen-binding fragment thereof provided herein.


In one aspect, the present disclosure provides a vector comprising the isolated polynucleotide provided herein.


In one aspect, the present disclosure provides a host cell comprising the vector provided herein.


In one aspect, the present disclosure provides a method of expressing the antibody or antigen-binding fragment thereof provided herein, comprising culturing the host cell provided herein under the condition at which the vector provided herein is expressed.


In one aspect, the present disclosure provides a method of treating a disease or condition in a subject that would benefit from modulation of CD276 activity, comprising administering to the subject a therapeutically effective amount of the antibody or antigen-binding fragment thereof provided herein or the pharmaceutical composition provided herein.


In some embodiments, the disease or condition is a CD276 related disease or condition.


In some embodiments, the disease or condition is cancer, adaptive immune disease, autoimmune disease, inflammatory disease, or infectious disease.


In some embodiments, the cancer is adrenal gland tumor, an AIDS-associated cancer, an alveolar soft part sarcoma, an astrocytic tumor, bladder cancer, bone cancer, a brain and spinal cord cancer, a metastatic brain tumor, a breast cancer, a carotid body tumors, a cervical cancer, a chondrosarcoma, a chordoma, a chromophobe renal cell carcinoma, a clear cell carcinoma, a colon cancer, a colorectal cancer, a cutaneous benign fibrous histiocytoma, a desmoplastic small round cell tumor, an ependymoma, a Ewing's tumor, an extraskeletal myxoid chondrosarcoma, a fibrogenesis imperfecta ossium, a fibrous dysplasia of the bone, a gallbladder or bile duct cancer, gastric cancer, a gestational trophoblastic disease, a germ cell tumor, a head and neck cancer, hepatocellular carcinoma, an islet cell tumor, a Kaposi's Sarcoma, a kidney cancer, a leukemia, a lipoma/benign lipomatous tumor, a liposarcoma/malignant lipomatous tumor, a liver cancer, a lymphoma, a lung cancer, a medulloblastoma, a melanoma, a meningioma, a multiple endocrine neoplasia, a multiple myeloma, a myelodysplastic syndrome, a neuroblastoma, a neuroendocrine tumors, an ovarian cancer, a pancreatic cancer, a papillary thyroid carcinoma, a parathyroid tumor, a pediatric cancer, a peripheral nerve sheath tumor, a phaeochromocytoma, a pituitary tumor, a prostate cancer, a posterior uveal melanoma, a rare hematologic disorder, a renal metastatic cancer, a rhabdoid tumor, a rhabdomysarcoma, a sarcoma, a skin cancer, a soft-tissue sarcoma, a squamous cell cancer, a stomach cancer, a synovial sarcoma, a testicular cancer, a thymic carcinoma, a thymoma, a thyroid metastatic cancer, and a uterine cancer, optionally, wherein the cancer is chemoresistant.


In some embodiments, the disease or condition is hematological cancer selected from B-cell lymphomas, such as Hodgkin's lymphoma, non-Hodgkin's lymphoma (NHL), acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), chronic myelogenous leukemia (CML), multiple myeloma (MM), diffuse large B cell lymphoma (DLBCL), Marginal zone B-cell lymphoma (MZL), Mantle cell lymphoma (MCL), Richter's syndrome, Burkitt's lymphoma or follicular lymphoma.


In some embodiments, the subject is human.


In some embodiments, the method provided herein comprises administering to the subject a therapeutically effective amount of one or more therapeutic agent. In some embodiments, said therapeutic agent is a chemotherapeutic agent, a radiation therapeutic agent, a hormonal therapeutic agent, a toxin or an immunotherapeutic agent.


In some embodiments, the second therapeutic agent is a PD-L1 antagonist.


In some embodiments, the PD-L1 antagonist is an anti-PD-L1 antibody or antigen-binding fragment thereof.


In some embodiments, the administration is via oral, nasal, intravenous, subcutaneous, sublingual, or intramuscular administration.


In some embodiments, said method further comprises administration of one or more additional cancer therapies selected from the group consisting of chemotherapy, immunotherapy, radiation therapy, hormonal therapy, and surgery.


In one aspect, the present disclosure provides a method of modulating CD276 activity in a CD276-expressing cell, comprising exposing the CD276-expressing cell to the antibody or antigen-binding fragment thereof provided herein.


In one aspect, the present disclosure provides a method of detecting presence or amount of CD276 in a sample, comprising contacting the sample with the antibody or antigen-binding fragment thereof provided herein, and determining the presence or the amount of CD276 in the sample.


In one aspect, the present disclosure provides a method of diagnosing a CD276 related disease or condition in a subject, comprising: a) obtaining a sample from the subject; b) contacting the sample obtained from the subject with the antibody or antigen-binding fragment thereof provided herein; c) determining presence or amount of CD276 in the sample; and d) correlating the presence or the amount of CD276 to existence or status of the CD276 related disease or condition in the subject.


In one aspect, the present disclosure provides use of the antibody or antigen-binding fragment thereof provided herein in the manufacture of a medicament for treating a CD276 related disease or condition in a subject.


In some embodiments, the medicament further comprises a second therapeutic agent. In some embodiments, the second therapeutic agent is a chemotherapeutic agent, a radiation therapeutic agent, a hormonal therapeutic agent, a toxin or an immunotherapeutic agent.


In some embodiments, the second therapeutic agent is a PD-L1 antagonist. In some embodiments, the PD-L1 antagonist is an anti-PD-L1 antibody or antigen-binding fragment thereof.


In one aspect, the present disclosure provides use of the antibody or antigen-binding fragment thereof provided herein in the manufacture of a diagnostic reagent for diagnosing a CD276 related disease or condition.


In one aspect, the present disclosure provides a kit comprising the antibody or antigen-binding fragment thereof provided herein, useful in detecting CD276, optionally recombinant CD276, CD276 expressed on cell surface, or CD276-expressing cells.


In one aspect, the present disclosure provides a chimeric antigen receptor (CAR) comprising an antigen binding domain, a transmembrane domain, a costimulatory signaling region, and a TCR signaling domain, wherein the antigen binding domain specifically binds to CD276 and comprises an antigen binding fragment provided herein. In some embodiments, the antigen binding fragment is a Fab or a scFv.


In some embodiments, the CAR provided herein is bispecific.


In some embodiments, the CAR is capable of further specifically binding to a second antigen other than CD276, or a second epitope on CD276. In some embodiments, the second antigen is a tumor antigen.


In some embodiments, the TCR signaling domain is selected from the group consisting of: an intracellular signal regions sequence of CD3ζ, FccRIγ, CD27, CD28, CD137, CD134, MyD88, CD40, CD278, TLRs, or a combination thereof.


In some embodiments, the transmembrane region comprises a transmembrane region of CD3, CD4, CD8 or CD28.


In one aspect, the present disclosure provides a nucleic acid sequence encoding the chimeric antigen receptor (CAR) provided herein. In one aspect, the present disclosure provides a cell comprising the nucleic acid sequence provided herein. In one aspect, the present disclosure provides a cell genetically modified to express the CAR provided herein. In some embodiments, the cell is immune cell, optionally, wherein the immune cell is T lymphocyte, NK cell, monocyte, macrophage or NKT lymphocyte.


In one aspect, the present disclosure provides a vector comprising the nucleic acid sequence provided herein.


In one aspect, the present disclosure provides a method for stimulating a T cell-mediated immune response to a CD276-expressing cell or tissue in a mammal, the method comprising administering to the mammal an effective amount of a cell genetically modified to express the CAR provided herein.


In one aspect, the present disclosure provides a method of treating a mammal having a CD276 related disease or condition, comprising administering to the mammal an effective amount of a cell provided herein, thereby treating the mammal. In some embodiments, the cell is an autologous T cell.


In some embodiments, the CD276 related disease or condition is cancer.


In some embodiments, the mammal is a human subject.


In one aspect, the present disclosure provides use of a cell genetically modified to express the CAR provided herein in the manufacture of a medicament for stimulating a T cell-mediated immune response to a CD276-expressing cell or tissue in a mammal.


In one aspect, the present disclosure provides use a cell provided herein in the manufacture of a medicament for treating a mammal having a CD276 related disease or condition.





BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are for illustration purposes only not for limitation.



FIG. 1 shows the binding affinity of the anti-CD276 antibodies provided herein on SKOV3 cells as measured by FACs analysis.



FIG. 2A-2E show binding of 6-D8-E7-A11 to several cancer cell lines that express B7H3 as measured by FACS analysis.



FIG. 3A-3C show ADCC effect of the anti-CD276 antibodies provided herein on SKOV3 cells.



FIGS. 4A and 4B show CDC effect of the anti-CD276 antibodies provided herein on CHO-S-hCD276 cells.



FIG. 5A-5E show indirect ADC cytotoxicity effect of the anti-CD276 antibodies provided herein on SKOV3 cells.



FIG. 6 shows in vivo efficacy of the anti-CD276 antibodies provided herein in inhibiting the tumor growth in the mouse model inoculated with MC-38-hCD276 (B7H3) tumor cells.



FIG. 7 shows effects on tumor growth in subcutaneous calu-6 model in balb/c nude mice (mean±sem).



FIG. 8 shows IL2 release by T cell activation in MLR assay.



FIG. 9 shows IFNγ release by T cell activation in MLR assay.



FIG. 10 shows the binding affinity on SKOV3 of humanized antibodies derived from 30-C7-C11-D4.



FIG. 11 shows binding affinity on SKOV3 of humanized antibodies derived from 10-G6-C4-B2.



FIG. 12 shows effects on tumor growth in subcutaneous Calu-6 model in Balb/c nude mice (Mean±SEM).





DETAILED DESCRIPTION OF THE INVENTION

The following description of the disclosure is merely intended to illustrate various embodiments of the disclosure. As such, the specific modifications discussed are not to be construed as limitations on the scope of the disclosure. It will be apparent to one skilled in the art that various equivalents, changes, and modifications may be made without departing from the scope of the disclosure, and it is understood that such equivalent embodiments are to be included herein. All references cited herein, including publications, patents and patent applications are incorporated herein by reference in their entirety.


Definitions

The term “antibody” as used herein includes any immunoglobulin, monoclonal antibody, polyclonal antibody, multivalent antibody, bivalent antibody, or monovalent antibody that binds to a specific antigen. A native intact antibody comprises two heavy (H) chains and two light (L) chains. Mammalian heavy chains are classified as alpha, delta, epsilon, gamma, and mu, each heavy chain consists of a variable region (VH) and a first, second, and third constant region (CH1, CH2, CH3, respectively); mammalian light chains are classified as λ or κ, while each light chain consists of a variable region (VL) and a constant region. The antibody has a “Y” shape, with the stem of the Y consisting of the second and third constant regions of two heavy chains bound together via disulfide bonding. Each arm of the Y includes the variable region and first constant region of a single heavy chain bound to the variable and constant regions of a single light chain. The variable regions of the light and heavy chains are responsible for antigen binding. The variable regions in both chains generally contain three highly variable loops called the complementarity determining regions (CDRs) (light chain CDRs including LCDR1, LCDR2, and LCDR3, heavy chain CDRs including HCDR1, HCDR2, and HCDR3). CDR boundaries for the antibodies and antigen-binding domains disclosed herein may be defined or identified by the conventions of Kabat, IMGT, AbM, Chothia, or A1-Lazikani (A1-Lazikani, B., Chothia, C., Lesk, A. M., J. Mol. Biol., 273 (4), 927 (1997); Chothia, C. et al., J Mol Biol. Dec 5; 186 (3): 651-63 (1985); Chothia, C. and Lesk, A. M., J. Mol. Biol., 196,901 (1987); N. R. Whitelegg et al, Protein Engineering, v13 (12), 819-824 (2000); Chothia, C. et al., Nature. Dec 21-28; 342 (6252): 877-83 (1989); Kabat E. A. et al., National Institutes of Health, Bethesda, Md. (1991); Marie-Paule Lefranc et al, Developmental and Comparative Immunology, 27:55-77 (2003); Marie-Paule Lefranc et al, Immunome Research, 1 (3), (2005); Marie-Paule Lefranc, Molecular Biology of B cells (second edition), chapter 26, 481-514, (2015)). The three CDRs are interposed between flanking stretches known as framework regions (FRs), which are more highly conserved than the CDRs and form a scaffold to support the hypervariable loops. The constant regions of the heavy and light chains are not involved in antigen-binding, but exhibit various effector functions. Antibodies are assigned to classes based on the amino acid sequence of the constant region of their heavy chain. The five major classes or isotypes of antibodies are IgA, IgD, IgE, IgG, and IgM, which are characterized by the presence of alpha, delta, epsilon, gamma, and mu heavy chains, respectively. Several of the major antibody classes are divided into subclasses such as IgG1 (gamma1 heavy chain), IgG2 (gamma2 heavy chain), IgG3 (gamma3 heavy chain), IgG4 (gamma4 heavy chain), IgA1 (alpha1 heavy chain), or IgA2 (alpha2 heavy chain).


The term “antibody molecule” as used herein refers to an antigen-binding protein or polypeptide comprising at least one antibody fragment (such as CDR, and/or variable region sequence). An antibody molecule includes, for example, a monoclonal antibody, an antibody fragment or domain, a fusion protein comprising an antibody fragment or domain, a polypeptide complex comprising an antibody fragment or domain, and so on.


The term “antigen-binding domain” (e.g. CD276-binding domain) as used herein refers to an antibody fragment formed from a portion of an antibody comprising one or more CDRs, or any other antibody fragment that binds to an antigen but does not comprise an intact native antibody structure. Examples of antigen-binding domain include, without limitation, a Fab, a Fab′, a F(ab′)2, an Fv fragment, a disulfide stabilized Fv fragment (dsFv), a (dsFv)2, a single-chain antibody molecule (scFv), a camelized single domain antibody, a nanobody, a domain antibody, and a bivalent domain antibody. An antigen-binding domain is capable of binding to the same antigen to which the parent antibody binds. In certain embodiments, an antigen-binding domain may comprise one or more CDRs from a particular human antibody grafted to a framework region from one or more different human antibodies. For more and detailed formats of antigen-binding domain are described in Spiess et al, 2015, and Brinkman et al., mAbs, 9 (2), pp. 182-212 (2017), which are incorporated herein by entirety reference.


“Fab” with regard to an antibody refers to that portion of the antibody consisting of a single light chain (both variable and constant regions) bound to the variable region and first constant region of a single heavy chain by a disulfide bond.


“Fab′” refers to a Fab fragment that includes a portion of the hinge region.


“F(ab′)2” refers to a dimer of Fab′.


A “fragment difficult (Fd)” with regard to an antibody refers to the amino-terminal half of the heavy chain fragment that can be combined with the light chain to form Fab. For example, Fd fragment may consists of the VH and CH1 domains


“Fv” with regard to an antibody refers to the smallest fragment of the antibody to bear the complete antigen-binding site. An Fv fragment consists of the variable region of a single light chain bound to the variable region of a single heavy chain. A number of Fv designs have been provided, including dsFvs, in which the association between the two domains is enhanced by an introduced disulphide bond; and scFvs can be formed using a peptide linker to bind the two domains together as a single polypeptide. Fvs constructs containing a variable domain of a heavy or light immunoglobulin chain associated to the variable and constant domain of the corresponding immunoglobulin heavy or light chain have also been produced.


“Single-chain Fv antibody” or “scFv” refers to an engineered antibody consisting of a light chain variable region and a heavy chain variable region connected to one another directly or via a peptide linker sequence (Huston J S et al. Proc Natl Acad Sci USA, 85: 5879 (1988)).


A “dsFv” refers to a disulfide-stabilized Fv fragment that the linkage between the variable region of a single light chain and the variable region of a single heavy chain is a disulfide bond. In some embodiments, a “(dsFv)2” or “(dsFv-dsFv′)” comprises three peptide chains: two VH moieties linked by a peptide linker (e.g., a long flexible linker) and bound to two VL moieties, respectively, via disulfide bridges. In some embodiments, dsFv-dsFv′ is bispecific in which each disulfide paired heavy and light chain has a different antigen specificity.


“Fc” with regard to an antibody refers to that portion of the antibody consisting of the second and third constant regions of a first heavy chain bound to the second and third constant regions of a second heavy chain via disulfide bonding. The Fc portion of the antibody is responsible for various effector functions such as antibody-dependent cell-mediated cytotoxicity (ADCC), and complement dependent cytotoxicity (CDC), but does not function in antigen binding.


“Camelized single domain antibody,” “heavy chain antibody,” or “HCAb” refers to an antibody that contains two VH domains and no light chains (Riechmann L. and Muyldermans S., J Immunol Methods. Dec 10; 231 (1-2): 25-38 (1999); Muyldermans S., J Biotechnol. Jun; 74 (4): 277-302 (2001); WO94/04678; WO94/25591; U.S. Pat. No. 6,005,079). Heavy chain antibodies were originally derived from Camelidae (camels, dromedaries, and llamas). Although devoid of light chains, camelized antibodies have an authentic antigen-binding repertoire (Hamers-Casterman C. et al., Nature. Jun 3; 363 (6428): 446-8 (1993); Nguyen V K. et al. “Heavy-chain antibodies in Camelidae; a case of evolutionary innovation,” Immunogenetics. Apr; 54 (1): 39-47 (2002); Nguyen V K. et al. Immunology. May; 109 (1): 93-101 (2003)). The variable domain of a heavy chain antibody (VHH domain) represents the smallest known antigen-binding unit generated by adaptive immune responses (Koch-Nolte F. et al., FASEB J. Nov; 21 (13): 3490-8. Epub 2007 Jun. 15 (2007)).


A “nanobody” refers to an antibody fragment that consists of a VHH domain from a heavy chain antibody and two constant domains, CH2 and CH3.


A “domain antibody” refers to an antibody fragment containing only the variable region of a heavy chain or the variable region of a light chain. In certain instances, two or more VH domains are covalently joined with a peptide linker to create a bivalent or multivalent domain antibody. The two VH domains of a bivalent domain antibody may target the same or different antigens.


The term “chimeric” as used herein, means an antibody or antigen-binding domain, having a portion of heavy and/or light chain derived from one species, and the rest of the heavy and/or light chain derived from a different species. In an illustrative example, a chimeric antibody may comprise a constant region derived from human and a variable region from a non-human animal, such as from mouse. In some embodiments, the non-human animal is a mammal, for example, a mouse, a rat, a rabbit, a goat, a sheep, a guinea pig, or a hamster.


The term “humanized” as used herein means that the antibody or antigen-binding domain comprises CDRs derived from non-human animals, FR regions derived from human, and when applicable, the constant regions derived from human.


The term “operably link” or “operably linked” refers to a juxtaposition, with or without a spacer or a linker or an intervening sequence, of two or more biological sequences of interest in such a way that they are in a relationship permitting them to function in an intended manner. When used with respect to polypeptides, it is intended to mean that the polypeptide sequences are linked in such a way that permits the linked product to have the intended biological function. For example, an antibody variable region may be operably linked to a constant region so as to provide for a stable product with antigen-binding activity. For another example, an antigen-binding domain can be operably linked to another antigen-binding domain with an intervening sequence there between, and such intervening sequence can be a spacer or can comprise a much longer sequence such as a constant region of an antibody. The term may also be used with respect to polynucleotides. For one instance, when a polynucleotide encoding a polypeptide is operably linked to a regulatory sequence (e.g., promoter, enhancer, silencer sequence, etc.), it is intended to mean that the polynucleotide sequences are linked in such a way that permits regulated expression of the polypeptide from the polynucleotide.


The term “fusion” or “fused” when used with respect to amino acid sequences (e.g. peptide, polypeptide or protein) refers to combination of two or more amino acid sequences, for example by chemical bonding or recombinant means, into a single amino acid sequence which does not exist naturally. A fusion amino acid sequence may be produced by genetic recombination of two encoding polynucleotide sequences, and can be expressed by a method of introducing a construct containing the recombinant polynucleotides into a host cell.


An “antigen” as used herein refers to a compound, composition, peptide, polypeptide, protein or substance that can stimulate the production of antibodies or a T cell response in cell culture or in an animal, including compositions (such as one that includes a cancer-specific protein) that are added to a cell culture (such as a hybridoma), or injected or absorbed into an animal. An antigen reacts with the products of specific humoral or cellular immunity (such as an antibody), including those induced by heterologous antigens.


The term “CD276 protein” or “B7-H3 protein” as used herein is intended to encompass any form of CD276, for example, 1) native unprocessed CD276 molecule, “full-length” CD276 chain or naturally occurring variants of CD276, including, for example, splice variants or allelic variants; 2) any form of CD276 that results from processing in the cell; or 3) full length, a fragment (e.g., a truncated form, an extracellular/transmembrane domain) or a modified form (e.g. a mutated form, a glycosylated/PEGylated, a His-tag/immunofluorescence fused form) of CD276 subunit generated through recombinant method.


The term “anti-CD276 antibody”, “anti-CD276 binding domain” or “CD276-binding domain” refers to an antibody or antigen-binding domain that is capable of specifically binding to CD276 (e.g. human, monkey or mouse CD276).


The term “specific binding” or “specifically binds” as used herein refers to a non-random binding reaction between two molecules, such as for example between an antibody and an antigen.


Binding of the antibodies to recombinant CD276 or CD276 expressed on surface of cells can also be represented by “half maximal effective concentration” (EC50) value, which refers to the concentration of an antibody where 50% of its maximal effect (e.g., binding or inhibition etc.) is observed. The EC50 value can be measured by methods known in the art, for example, sandwich assay such as ELISA, Western Blot, flow cytometry assay, and other binding assays. In certain embodiments, the antibodies and the fragments thereof provided herein specifically bind to recombinant human CD276 at an EC50 (i.e. 50% binding concentration) of no more than 0.05 nM, no more than 0.06 nM, no more than 0.07 nM, no more than 0.08 nM, no more than 0.09 nM, no more than 0.1 nM, no more than 0.2 nM, no more than 0.3 nM, no more than 0.4 nM, no more than 0.5 nM, no more than 0.6 nM, no more than 0.7 nM, no more than 0.8 nM, no more than 0.9 nM, no more than 1 nM, no more than 1.5 nM, no more than 2 nM, no more than 2.5 nM, no more than 3.5 nM, no more than 3 nM, no more than 4 nM, no more than 4.5 nM, no more than 5 nM, no more than 6 nM, no more than 7 nM, no more than 8 nM, no more than 9 nM, or no more than 10 nM, by flow cytometry assay.


The ability to “block binding” or “compete for the same epitope” as used herein refers to the ability of an antibody or antigen-binding domain to inhibit the binding interaction between two molecules (e.g. human CD276 and its binding ligand, e.g. TLT-2) to any detectable degree. In certain embodiments, an antibody or antigen-binding domain that blocks binding between two molecules inhibits the binding interaction between the two molecules by at least 85%, or at least 90%. In certain embodiments, this inhibition may be greater than 85%, or greater than 90%.


The term “epitope” as used herein refers to the specific group of atoms or amino acids on an antigen to which an antibody binds. Epitopes can be formed both from contiguous amino acids (also called linear or sequential epitope) or noncontiguous amino acids juxtaposed by tertiary folding of a protein (also called configurational or conformational epitope). Epitopes formed from contiguous amino acids are typically arranged linearly along the primary amino acid residues on the protein and the small segments of the contiguous amino acids can be digested from an antigen binding with major histocompatibility complex (MHC) molecules or retained on exposure to denaturing solvents whereas epitopes formed by tertiary folding are typically lost on treatment with denaturing solvents. An epitope typically includes at least 3, and more usually, at least 5, about 7, or about 8-10 amino acids in a unique spatial conformation. Two antibodies may bind the same or a closely related epitope within an antigen if they exhibit competitive binding for the antigen. For example, if an antibody or antigen-binding domain blocks binding of a reference antibody to the antigen by at least 85%, or at least 90%, or at least 95%, then the antibody or antigen-binding domain may be considered to bind the same/closely related epitope as the reference antibody.


A “conservative substitution” with reference to amino acid sequence refers to replacing an amino acid residue with a different amino acid residue having a side chain with similar physiochemical properties. For example, conservative substitutions can be made among amino acid residues with hydrophobic side chains (e.g. Met, Ala, Val, Leu, and Ile), among residues with neutral hydrophilic side chains (e.g. Cys, Ser, Thr, Asn and Gln), among residues with acidic side chains (e.g. Asp, Glu), among amino acids with basic side chains (e.g. His, Lys, and Arg), or among residues with aromatic side chains (e.g. Trp, Tyr, and Phe). As known in the art, conservative substitution usually does not cause significant change in the protein conformational structure, and therefore could retain the biological activity of a protein.


The term “homolog” and “homologous” as used herein are interchangeable and refer to nucleic acid sequences (or its complementary strand) or amino acid sequences that have sequence identity of at least 80% (e.g., at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%) to another sequences when optimally aligned.


“Percent (%) sequence identity” with respect to amino acid sequence (or nucleic acid sequence) is defined as the percentage of amino acid (or nucleic acid) residues in a candidate sequence that are identical to the amino acid (or nucleic acid) residues in a reference sequence, after aligning the sequences and, if necessary, introducing gaps, to achieve the maximum number of identical amino acids (or nucleic acids). Conservative substitution of the amino acid residues may or may not be considered as identical residues. Alignment for purposes of determining percent amino acid (or nucleic acid) sequence identity can be achieved, for example, using publicly available tools such as BLASTN, BLASTp (available on the website of U.S. National Center for Biotechnology Information (NCBI), see also, Altschul S. F. et al, J. Mol. Biol., 215:403-410 (1990); Stephen F. et al, Nucleic Acids Res., 25:3389-3402 (1997)), ClustalW2 (available on the website of European Bioinformatics Institute, see also, Higgins D. G. et al, Methods in Enzymology, 266:383-402 (1996); Larkin M. A. et al, Bioinformatics (Oxford, England), 23 (21): 2947-8 (2007)), and ALIGN or Megalign (DNASTAR) software. Those skilled in the art may use the default parameters provided by the tool, or may customize the parameters as appropriate for the alignment, such as for example, by selecting a suitable algorithm.


“Effector functions” as used herein refer to biological activities attributable to the binding of Fc region of an antibody to its effectors such as C1 complex, Fc receptor and effector cell (e.g., macrophage). Exemplary effector functions include: complement dependent cytotoxicity (CDC) induced by interaction of antibodies and C1q on the C1 complex; antibody-dependent cell-mediated cytotoxicity (ADCC) induced by binding of Fc region of an antibody to Fc receptor on an effector cell; and antibody-dependent cellular phagocytosis (ADCP) induced by binding of Fc region of an antibody to phagocytosis. It has become well established that the specific glycan structures associated with the conserved bi-antennary glycan in the Fc-CH2 domain can strongly influence the interaction with the FcyRs that mediate ADCC and ADCP and with C1q binding, the initial binding event leading to CDC (see Reusch D, Tejada M L. Fc glycans of therapeutic antibodies as critical quality attributes. Glycobiology 2015; 25:1325-34).


“Treating” or “treatment” of a condition as used herein includes preventing or alleviating a condition, slowing the onset or rate of development of a condition, reducing the risk of developing a condition, preventing or delaying the development of symptoms associated with a condition, reducing or ending symptoms associated with a condition, generating a complete or partial regression of a condition, curing a condition, or some combination thereof.


The term “subject” or “individual” or “animal” or “patient” as used herein refers to human or non-human animal, including a mammal or a primate, in need of diagnosis, prognosis, amelioration, prevention and/or treatment of a disease or disorder. Mammalian subjects include humans, monkeys, domestic animals, farm animals, and zoo, sports, or pet animals such as dogs, cats, guinea pigs, rabbits, rats, mice, horses, swine, cows, bears, and so on.


The term “vector” as used herein refers to a vehicle into which a polynucleotide encoding a protein may be operably inserted so as to bring about the expression of that protein. A vector may be used to transform, transduce, or transfect a host cell so as to bring about expression of the genetic element it carries within the host cell. Examples of vectors include plasmids, phagemids, cosmids, and artificial chromosomes such as yeast artificial chromosome (YAC), bacterial artificial chromosome (BAC), or P1-derived artificial chromosome (PAC), bacteriophages such as lambda phage or M13 phage, and animal viruses. Categories of animal viruses used as vectors include retrovirus (including lentivirus), adenovirus, adeno-associated virus, herpesvirus (e.g., herpes simplex virus), poxvirus, baculovirus, papillomavirus, and papovavirus (e.g., SV40). A vector may contain a variety of elements for controlling expression, including promoter sequences, transcription initiation sequences, enhancer sequences, selectable elements, and reporter genes. In addition, the vector may contain an origin of replication. A vector may also include materials to aid in its entry into the cell, including but not limited to a viral particle, a liposome, or a protein coating. A vector can be an expression vector or a cloning vector.


The phrase “host cell” as used herein refers to a cell into which an exogenous polynucleotide and/or a vector has been introduced.


A “CD276-related” disease or condition as used herein refers to any disease or condition caused by, exacerbated by, or otherwise linked to increased or decreased expression or activities of CD276. In some embodiments, the CD276 related condition is immune-related disorder, such as, for example, cancer, autoimmune disease, inflammatory disease or infectious disease.


“Cancer” as used herein refers to any medical condition characterized by malignant cell growth or neoplasm, abnormal proliferation, infiltration or metastasis, and includes both solid tumors and non-solid cancers (hematologic malignancies) such as leukemia. As used herein “solid tumor” refers to a solid mass of neoplastic and/or malignant cells. Examples of cancer or tumors include adrenal gland tumor, an AIDS-associated cancer, an alveolar soft part sarcoma, an astrocytic tumor, bladder cancer, bone cancer, a brain and spinal cord cancer, a metastatic brain tumor, a breast cancer, a carotid body tumors, a cervical cancer, a chondrosarcoma, a chordoma, a chromophobe renal cell carcinoma, a clear cell carcinoma, a colon cancer, a colorectal cancer, a cutaneous benign fibrous histiocytoma, a desmoplastic small round cell tumor, an ependymoma, a Ewing's tumor, an extraskeletal myxoid chondrosarcoma, a fibrogenesis imperfecta ossium, a fibrous dysplasia of the bone, a gallbladder or bile duct cancer, gastric cancer, a gestational trophoblastic disease, a germ cell tumor, a head and neck cancer, hepatocellular carcinoma, an islet cell tumor, a Kaposi's Sarcoma, a kidney cancer, a leukemia, a lipoma/benign lipomatous tumor, a liposarcoma/malignant lipomatous tumor, a liver cancer, a lymphoma, a lung cancer, a medulloblastoma, a melanoma, a meningioma, a multiple endocrine neoplasia, a multiple myeloma, a myelodysplastic syndrome, a neuroblastoma, a neuroendocrine tumors, an ovarian cancer, a pancreatic cancer, a papillary thyroid carcinoma, a parathyroid tumor, a pediatric cancer, a peripheral nerve sheath tumor, a phaeochromocytoma, a pituitary tumor, a prostate cancer, a posterior uveal melanoma, a rare hematologic disorder, a renal metastatic cancer, a rhabdoid tumor, a rhabdomysarcoma, a sarcoma, a skin cancer, a soft-tissue sarcoma, a squamous cell cancer, a stomach cancer, a synovial sarcoma, a testicular cancer, a thymic carcinoma, a thymoma, a thyroid metastatic cancer, and a uterine cancer.


In certain embodiments, the hematological malignancies includes B-cell lymphomas, optionally Hodgkin's lymphoma, non-Hodgkin's lymphoma (NHL), acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), chronic myelogenous leukemia (CML), multiple myeloma (MM), diffuse large B cell lymphoma (DLBCL), Marginal zone B-cell lymphoma (MZL), Mantle cell lymphoma (MCL), Richter's syndrome, Burkitt's lymphoma or follicular lymphoma.


In certain embodiments, the cancer is selected from gastric cancer, breast cancer, head and neck cancer, pancreatic cancer, and colon cancer. In certain embodiments, the cancer is selected from a lymphoma, Hodgkin's lymphoma, non-Hodgkin's lymphoma and B-cell lymphoma.


In certain embodiments, the cancer is chemoresistant. The term “chemoresistant cancer” as used herein refers to a type of cancer that are not responsive to the effects of chemotherapy. For example, a cancer that has been responding to a chemotherapy or a combination of different chemotherapies suddenly begins to grow can be referred to as a chemoresistant cancer.


The term “pharmaceutically acceptable” indicates that the designated carrier, vehicle, diluent, excipient(s), and/or salt is generally chemically and/or physically compatible with the other ingredients comprising the formulation, and physiologically compatible with the recipient thereof.


Anti-CD276 Antibody

The present disclosure provides anti-CD276 antibodies and antigen-binding fragments thereof comprising one or more (e.g. 1, 2, 3, 4, 5, or 6) CDR sequences of an anti-CD276 antibody 9-E8-F9-C10, 10-G6-C4-B2, 18-F9-D8-G7, 9-G2-H6-E4, 20-F8-B5-G2, 30-C7-C11-D4, 23-F10-G4-F11, 6-H11-G5-D8, 27-E7-D8-C7, 30-E2-G7-G7, 5-D1-G6-D9, 3-C2-C3-E7, 11-G10-B4-B11, 16-C6-F7-F5, 22-E11-C3-F2, 24-C10-F9-G7, 25-C8-D7-C5, 4-D5-B9-B11, 10-B9-D10-A12, 15-G1-D1-E3, 8-B4-F5-E11, 6-F3-G2-G1, 9-B9-H11-G7, 9-G12-D6-A11, 13-A8-C4-G1, 15-C8-B5-G7, 28-G2-E6-B10, 3-G7-D8-D3, 14-E7-G9-D4, 20-C5-D7-D3, 8-C3-E3-F3, 2-A7-B10-A3, 26-D2-D6-B12, 11-C12-F4-F6, 16-G3-D10-C10, 27-F8-E10-E11, 7-E1-F8-F6, 25-D3-G4-C6, 13-E4-G9-A4, 20-A2-D10-G8, 3-F2-E7-F9, 6-D8-E7-A11, and 21-B3-B1-H5. In certain embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof provided herein is capable of specifically binding to CD276. Optionally, the CD276 are derived from human, monkey or mouse. In certain embodiments, the CD276 is a recombinant CD276 or a CD276 expressed on a cell surface.


All of the anti-CD276 antibodies and antigen-binding fragments thereof provided herein are mouse monoclonal antibodies. Table 1 shows the CDR sequences of these 43 anti-CD276 antibodies according to IMGT numbering system. The heavy chain and light chain variable region sequences are also provided below.









TABLE 1







CDR sequences of the anti-CD276 antibodies











Antibody Clone

CDR1
CDR2
CDR3





9-E8-F9-C10
VH
SEQ ID NO: 1
SEQ ID NO: 2
SEQ ID NO: 3




GYAFSDYW
ICPGSGNI
TRLITRVIDY



VL
SEQ ID NO: 4
SEQ ID NO: 5
SEQ ID NO: 6




SSVNY
DTS
FQGSGYPLT





10-G6-C4-B2
VH
SEQ ID NO: 9
SEQ ID NO: 10
SEQ ID NO: 11




GFTLSDYY
MRNKANGYTT
VRDRDGRPFAY



VL
SEQ ID NO: 12
SEQ ID NO: 13
SEQ ID NO: 14




QSLLNSINQKNF
WAS
QNDYTYPLT





18-F9-D8-G7
VH
SEQ ID NO: 17
SEQ ID NO: 18
SEQ ID NO: 19




GYTFTDYA
INTYSGDT
ARGGGNYPYWYFDV



VL
SEQ ID NO: 20
SEQ ID NO: 21
SEQ ID NO: 22




SSVSSSY
STS
QQFSVYPLT





9-G2-H6-E4
VH
SEQ ID NO: 25
SEQ ID NO: 26
SEQ ID NO: 27




GYSFTGYF
INPNNGDT
GRGGLPFGALDY



VL
SEQ ID NO: 28
SEQ ID NO: 29
SEQ ID NO: 30




QSLLYSRNQKNY
WAS
QQYHSYPYT





20-F8-B5-G2
VH
SEQ ID NO: 33
SEQ ID NO: 34
SEQ ID NO: 35




GDSITSAY
ISNSGST
VRGERYYGYGAY



VL
SEQ ID NO: 36
SEQ ID NO: 37
SEQ ID NO: 38




KSLLHSNGNTYL Y
RMS
MQHLEYPFT





30-C7-C11-D4
VH
SEQ ID NO: 41
SEQ ID NO: 42
SEQ ID NO: 43




GYSITSDYA
SHSGST
ARSLGRRWYFDV



VL
SEQ ID NO: 44
SEQ ID NO: 45
SEQ ID NO: 46




QSLLNSSTQKNY
FAS
QQHYIIPFT





23-F10-G4-F11
VH
SEQ ID NO: 49
SEQ ID NO: 50
SEQ ID NO: 51




GFNIKDYP
FDPDNGNV
SSPYGAMDY



VL
SEQ ID NO: 52
SEQ ID NO: 53
SEQ ID NO: 54




SSVSY
DTS
QQGSSNPRT





6-H11-G5-D8
VH
SEQ ID NO: 57
SEQ ID NO: 58
SEQ ID NO: 59




GYTFTSYD
IFPGNGDT
ARDLRLGTFDY



VL
SEQ ID NO: 60
SEQ ID NO: 61
SEQ ID NO: 62




SSVSY
DTS
QQGSSNPRT





27-E7-D8-C7
VH
SEQ ID NO: 65
SEQ ID NO: 66
SEQ ID NO: 67




GYTFTDYA
INTYSDNT
ARGLLLRSQLGVYFDY



VL
SEQ ID NO: 68
SEQ ID NO: 69
SEQ ID NO: 70




SSVSY
ATS
QQWSSNPWT





30-E2-G7-G7
VH
SEQ ID NO: 73
SEQ ID NO: 74
SEQ ID NO: 75




GFTFSYYA
INGDGSHT
ASLLQLGPF



VL
SEQ ID NO: 76
SEQ ID NO: 77
SEQ ID NO: 78




QNVGTN
SAS
QQYNNYPLT





5-D1-G6-D9
VH
SEQ ID NO: 81
SEQ ID NO: 82
SEQ ID NO: 83




GLTFSTNY
IYGGNGGT
TSHDYYGGPMDY



VL
SEQ ID NO: 84
SEQ ID NO: 85
SEQ ID NO: 86




QDISNY
FTS
QQTNTLPWT





3-C2-C3-E7
VH
SEQ ID NO: 89
SEQ ID NO: 90
SEQ ID NO: 91




GYTFTENT
INPNTGGT
ARRGTNWEHWYFDV



VL
SEQ ID NO: 92
SEQ ID NO: 93
SEQ ID NO: 94




SSVSY
DTS
QQWSSNPLT





11-G10-B4-B11
VH
SEQ ID NO: 97
SEQ ID NO: 98
SEQ ID NO: 99




GYSITSDYA
ISYSGST
ARGGPWFAY



VL
SEQ ID NO: 100
SEQ ID NO: 101
SEQ ID NO: 102




QSL VHSNGNTY
KVS
SQSTHVPFT





16-C6-F7-F5
VH
SEQ ID NO: 105
SEQ ID NO: 106
SEQ ID NO: 107




GYTFTKYG
IWTYTGKP
ARDDGYYYTMNY



VL
SEQ ID NO: 108
SEQ ID NO: 109
SEQ ID NO: 110




QSLLHTNGDTY
KVS
SQSTHIPWT





22-E11-C3-F2
VH
SEQ ID NO: 113
SEQ ID NO: 114
SEQ ID NO: 115




GYSFTNYG
NPYTGEP
GRDDGYHYTMNY



VL
SEQ ID NO: 116
SEQ ID NO: 117
SEQ ID NO: 118




QSLIHSNGDTY
KVS
SQSTYVPWT





24-C10-F9-G7
VH
SEQ ID NO: 121
SEQ ID NO: 122
SEQ ID NO: 123




GYTFTDHT
ISTYYGNT
ARASYGSGYGPYYWY






FDV



VL
SEQ ID NO: 124
SEQ ID NO: 125
SEQ ID NO: 126




EKIYSY
NAN
QHHYGTPVT





25-C8-D7-C5
VH
SEQ ID NO: 129
SEQ ID NO: 130
SEQ ID NO: 131




GFTFSTYA
ISGGGIDT
ARQGSKGWGAMDY



VL
SEQ ID NO: 132
SEQ ID NO: 133
SEQ ID NO: 134




SSVSF
ETS
QQWSSNPLT





4-D5-B9-B11
VH
SEQ ID NO: 137
SEQ ID NO: 138
SEQ ID NO: 139




GFTFSSYA
ISGGGI
ARQGSKGWDAMDY



VL
SEQ ID NO: 140
SEQ ID NO: 141
SEQ ID NO: 142




SSVSF
ETS
QQWSSNPLT





10-B9-D10-A12
VH
SEQ ID NO: 145
SEQ ID NO: 146
SEQ ID NO: 147




GYTFTDYT
ISTYYGNT
ARASYGSGYGPYYWY






FDV



VL
SEQ ID NO: 148
SEQ ID NO: 149
SEQ ID NO: 150




EKIYSY
NAN
QHHYGTPVT





15-G1-D1-E3
VH
SEQ ID NO: 153
SEQ ID NO: 154
SEQ ID NO: 155




GYTFTSYW
IHPKSGTV
ARGENYDYRPQFVY



VL
SEQ ID NO: 156
SEQ ID NO: 157
SEQ ID NO: 158




SQHSTYT
LKKDGSH
GVGDTIKEQFVYV





8-B4-F5-E11
VH
SEQ ID NO: 161
SEQ ID NO: 162
SEQ ID NO: 163




GDTFTSYW
IHPDSGTR
CSRSYGSRLAWFAY



VL
SEQ ID NO: 164
SEQ ID NO: 165
SEQ ID NO: 166




TGAVTTSNF
GTN
ALWYTNHFI





6-F3-G2-G1
VH
SEQ ID NO: 169
SEQ ID NO: 170
SEQ ID NO: 171




DYTFTNYW
IHPNSGTT
ASHYGNSYSAMDY



VL
SEQ ID NO: 172
SEQ ID NO: 173
SEQ ID NO: 174




TGAVTTSNY
GTS
ALWYSTHYV





9-B9-H11-G7
VH
SEQ ID NO: 177
SEQ ID NO: 178
SEQ ID NO: 179




GYSITSGYY
YISYDGTN
ARGDSNSYYFDY



VL
SEQ ID NO: 180
SEQ ID NO: 181
SEQ ID NO: 182




TGAVTTSNY
GTS
ALWYRTHYV





9-G12-D6-A11
VH
SEQ ID NO: 185
SEQ ID NO: 186
SEQ ID NO: 187




GYSITSDYY
ISYDGTN
ARGKDGSYYFDY



VL
SEQ ID NO: 188
SEQ ID NO: 189
SEQ ID NO: 190




TGAVTTSNY
GTS
ALWYRTHYV





13-A8-C4-G1
VH
SEQ ID NO: 193
SEQ ID NO: 194
SEQ ID NO: 195




SGYIFTSNW
IHPNSGTT
AGPTTTRRFYPMDY



VL
SEQ ID NO: 196
SEQ ID NO: 197
SEQ ID NO: 198




TGAVTTSNY
GTN
AL WYSNHFI





15-C8-B5-G7
VH
SEQ ID NO: 201
SEQ ID NO: 202
SEQ ID NO: 203




DYTFTSHWMHW
IHPNSGTT
AWGSSNSYFYAMAY



VL
SEQ ID NO: 204
SEQ ID NO: 205
SEQ ID NO: 206




TGAVTTSNY
GTN
ALWFSNHL V





28-G2-E6-B10
VH
SEQ ID NO: 209
SEQ ID NO: 210
SEQ ID NO: 211




GYTFTSYW
IHPNSDTT
ARGGLGPHYFVY



VL
SEQ ID NO: 212
SEQ ID NO: 213
SEQ ID NO: 214




TGAVTTSNY
GTS
ALWYSPHYV





3-G7-D8-D3
VH
SEQ ID NO: 217
SEQ ID NO: 218
SEQ ID NO: 219




GYTFTTYW
IYPGDGDT
ARPYDGYYIDYPMDS



VL
SEQ ID NO: 220
SEQ ID NO: 221
SEQ ID NO: 222




SRINY
DTS
HQRSSYPFT





14-E7-G9-D4
VH
SEQ ID NO: 225
SEQ ID NO: 226
SEQ ID NO: 227




GYTFTNYI
INPYNDGI
TRWGNYVFYYTMDY



VL
SEQ ID NO: 228
SEQ ID NO: 229
SEQ ID NO: 230




SSVSY
ATS
QQWSGNPPLT





20-C5-D7-D3
VH
SEQ ID NO: 233
SEQ ID NO: 234
SEQ ID NO: 235




GFTFRSYG
ISGGGNYT
ARHEGLPLDY



VL
SEQ ID NO: 236
SEQ ID NO: 237
SEQ ID NO: 238




ENIYSY
NAK
QHHYGTPTWT





8-C3-E3-F3
VH
SEQ ID NO: 241
SEQ ID NO: 242
SEQ ID NO: 243




GFTFSNYG
IGSYGGNTY
ARDIYYGNSEAWFAY



VL
SEQ ID NO: 244
SEQ ID NO: 245
SEQ ID NO: 246




KSLLHSNGITY
QMS
AQNLELPWT





2-A7-B10-A3
VH
SEQ ID NO: 249
SEQ ID NO: 250
SEQ ID NO: 251




GYTFTDYA
INTNYVNT
ARGGKYGNYVFFFAY



VL
SEQ ID NO: 252
SEQ ID NO: 253
SEQ ID NO: 254




QDISNY
YTS
QQGNTLPYT





26-D2-D6-B12
VH
SEQ ID NO: 257
SEQ ID NO: 258
SEQ ID NO: 259




GYIFRNYG
INSYTGKPTY
ARDDGYWYTMDY



VL
SEQ ID NO: 260
SEQ ID NO: 261
SEQ ID NO: 262




QSL VHSNGHTY
KVS
SQSTHVPWT





11-C12-F4-F6
VH
SEQ ID NO: 265
SEQ ID NO: 266
SEQ ID NO: 267




GYTFRNFG
INPYTGEP
ARDDGYWYTMDY



VL
SEQ ID NO: 268
SEQ ID NO: 269
SEQ ID NO: 270




QSL VHSNGITY
KVS
SQSTHVPWT





16-G3-D10-C10
VH
SEQ ID NO: 273
SEQ ID NO: 274
SEQ ID NO: 275




GYTFRNYG
INPYTGEP
ARDDGYWYTMDY



VL
SEQ ID NO: 276
SEQ ID NO: 277
SEQ ID NO: 278




QSL VHSNGITY
KVS
SQSTHVPWT





27-F8-E10-E11
VH
SEQ ID NO: 281
SEQ ID NO: 282
SEQ ID NO: 283




GYTFTEYA
INPNIGGT
ARFL VPSTEGFTY



VL
SEQ ID NO: 284
SEQ ID NO: 285
SEQ ID NO: 286




SSVSY
DTS
QQWSSNPLT





7-E1-F8-F6
VH
SEQ ID NO: 289
SEQ ID NO: 290
SEQ ID NO: 291




GYTFTDYV
IYPRSGNT
ARFDIA YSFDY



VL
SEQ ID NO: 292
SEQ ID NO: 293
SEQ ID NO: 294




QSL VHSNGVTY
KVS
SQGTHVPWT





25-D3-G4-C6
VH
SEQ ID NO: 297
SEQ ID NO: 298
SEQ ID NO: 299




GYSFTDYI
INPYYNST
ARDSFDWYFGV



VL
SEQ ID NO: 300
SEQ ID NO: 301
SEQ ID NO: 302




QSL VHSNGNTY
KVS
SQSTHVPPLT





13-E4-G9-A4
VH
SEQ ID NO: 305
SEQ ID NO: 306
SEQ ID NO: 307




GFTFITYA
ISGGGIDT
TRQGSQGWGAMDY



VL
SEQ ID NO: 308
SEQ ID NO: 309
SEQ ID NO: 310




SRVSF
ETS
QQWSSNPLT





20-A2-D10-G8
VH
SEQ ID NO: 313
SEQ ID NO: 314
SEQ ID NO: 315




GYTFTDYT
ISTYYGNT
ARASYGSGYGPYYWY






FDV



VL
SEQ ID NO: 316
SEQ ID NO: 317
SEQ ID NO: 318




EKIYSY
NAN
QHHYGSPVT





3-F2-E7-F9
VH
SEQ ID NO: 321
SEQ ID NO: 322
SEQ ID NO: 323




GYTFTDYT
ISTYYGNT
ARASYGSGYGPYYWY






FDV



VL
SEQ ID NO: 324
SEQ ID NO: 325
SEQ ID NO: 326




EKIYSY
NAN
QHHYGTPVT





6-D8-E7-A11
VH
SEQ ID NO: 329
SEQ ID NO: 330
SEQ ID NO: 331




GYTFTNYW
IHPNSGTT
AGYYGSSFSWFTY



VL
SEQ ID NO: 332
SEQ ID NO: 333
SEQ ID NO: 334




TGAVTTSNF
GTS
ALWYSTHYV





21-B3-B1-H5
VH
SEQ ID NO: 337
SEQ ID NO: 338
SEQ ID NO: 339




GYIFRNYG
INSYTGKP
ARDDGYWYTMDY



VL
SEQ ID NO: 340
SEQ ID NO: 341
SEQ ID NO: 342




QSL VHSNGHTY
KVS
SQSTHVPWT









Heavy or light chain variable region sequences of 9-E8-F9-C10, 10-G6-C4-B2, 18-F9-D8-G7, 9-G2-H6-E4, 20-F8-B5-G2, 30-C7-C11-D4, 23-F10-G4-F11, 6-H11-G5-D8, 27-E7-D8-C7, 30-E2-G7-G7, 5-D1-G6-D9, 3-C2-C3-E7, 11-G10-B4-B11, 16-C6-F7-F5, 22-E11-C3-F2, 24-C10-F9-G7, 25-C8-D7-C5, 4-D5-B9-B11, 10-B9-D10-A12, 15-G1-D1-E3, 8-B4-F5-E11, 6-F3-G2-G1, 9-B9-H11-G7, 9-G12-D6-A11, 13-A8-C4-G1, 15-C8-B5-G7, 28-G2-E6-B10, 3-G7-D8-D3, 14-E7-G9-D4, 20-C5-D7-D3, 8-C3-E3-F3, 2-A7-B10-A3, 26-D2-D6-B12, 11-C12-F4-F6, 16-G3-D10-C10, 27-F8-E10-E11, 7-E1-F8-F6, 25-D3-G4-C6, 13-E4-G9-A4, 20-A2-D10-G8, 3-F2-E7-F9, 6-D8-E7-A11, and 21-B3-B1-H5 antibodies are provided in Table 2.









TABLE 2







Variable region sequences of the anti-CD276 antibodies









Clone
VH
VL





9-E8-F9-C10
SEQ ID NO: 7
SEQ ID NO: 8



EVQLQQSGAELVRPGTSVKISC
ENVLTQSPAIMSASPGEKVTM



KASGYAFSDYWLSWVKQRPG
TCSASSSVNYMHWYQQKSSTS



HGLEWIGDICPGSGNIYYNERF
PKLWIYDTSKLSSGVPGRFSGS



KDKVILTADRSSSTAYLQFSSL
GSGNSYSLTISSMEAEDVATY



TSEDSVVYFCTRLITRVIDYWG
YCFQGSGYPLTFGAGTKLELK



QGTSVTVST






10-G6-C4-B2
SEQ ID NO: 15
SEQ ID NO: 16



EVQLVESGGGLVQPGGSLRLSC
DIVMTQSPSSLTVTAGEKVTM



ATSGFTLSDYYMSWVRQPPGK
SCKSSQSLLNSINQKNFLTWY



APEWLGFMRNKANGYTTEYSA
QQKPGQPPKLLIYWASTRESG



SVRGRFTISRDTSQSIIYLQMNT
VPDRFTGSGSGTDFTLTISSVQ



LRAEDGATYYCVRDRDGRPFA
AEDLAIYYCQNDYTYPLTFGT



YWGQGTLVTVSA
GTKLELK





18-F9-D8-G7
SEQ ID NO: 23
SEQ ID NO: 24



EVQLQQSGPELVRPGVSVKISC
ENVLTQSPAIMSASPGEKVTM



KGSGYTFTDYAMHWVKQSHA
TCRASSSVSSSYLHWYQQKSG



QSLEWIGIINTYSGDTNYNQKF
DSPKLWIYSTSNLASGVPARFS



KGKATMTVDKSSSTAYMGLA
GSGSGTSYSLTISSVEAEDAAT



RLTSEDSAIFYCARGGGNYPY
YYCQQFSVYPLTFGAGTKLEI



WYFDVWGAGTTVTVSS
K





9-G2-H6-E4
SEQ ID NO: 31
SEQ ID NO: 32



EVQLQQSGPDLVKPGASVKISC
DIVMSQSPSSLAVSVGEKVNM



KASGYSFTGYFMNWVKQRHG
SCKSSQSLLYSRNQKNYLAWN



KSLEWIGYINPNNGDTIYNQKF
QQKPGQSPKLLIYWASARESG



KGKATLTVDKSSSTAHMELLS
VPDRFTGSGSGTDFTLTISSVK



LTSEDSAVYYCGRGGLPFGAL
AEDLAAYYCQQYHSYPYTFG



DYWGQGTSVTVSS
GGTKLELK





20-F8-B5-G2
SEQ ID NO: 39
SEQ ID NO: 40



EVQLQESGPSLVKPSQTLSLTC
DIVMTQATPSVPVTPGESISISC



SVTGDSITSAYWNWIRKFPGNK
RSSKSLLHSNGNTYLYWFLQR



LEYMGYISNSGSTYYNPSLKSR
PGQSPQLLIYRMSNLASGVPD



ISITRDTSKNQYYLQLNSVTTE
RFSGSGSGTAFTLRISRVEAED



DTGTYYCVRGERYYGYGAYW
VGVYYCMQHLEYPFTFGAGT



GQGTLVTVSA
KLELK





30-C7-C11-D4
SEQ ID NO: 47
SEQ ID NO: 48



EVQLVESGPGLVKPSQSLSLTC
DIVMTQSPSSLAMSVGQKVTL



TVTGYSITSDYAWNWIRQFPG
SCKSSQSLLNSSTQKNYLAWY



NKLEWMGYISHSGSTSYNPSLK
QQKPGQSPKLLVYFASTRDSG



SRISITRDTSKNQFFLQLNSVTT
VPDRFIGSGSGTEFTLTISSVQA



EDTATYYCARSLGRRWYFDV
EDLADYFCQQHYIIPFTFGAGT



WGAGTTVTVSS
KLEIK





23-F10-G4-
SEQ ID NO: 55
SEQ ID NO: 56


F11
EVQLQESGPDLVRPGALVKLSC
QIVLTQSPEIMSASPGEKVTMT



KSSGFNIKDYPIHWVRQRPEQG
CSASSSVSYIHWYQQKSGTSP



LEWIGWFDPDNGNVIYDPRFQ
KRWIYDTSKLASGVPARFSGS



GKASITADTSSNTAYLQLNSLT
GSGTSYSLTIRSMEAEDAATY



SEDTAVYYCSSPYGAMDYWG
YCQQGSSNPRTFGGGTKLEIK



QGTSVTVSS






6-H11-G5-D8
SEQ ID NO: 63
SEQ ID NO: 64



EVQLQESGPELVKPGTSVKLSC
QIVLTQSPEIMSASPGEKVTMT



KASGYTFTSYDINWVRQRPEQ
CSASSSVSYIHWYQQKSGTSP



GLEWIGWIFPGNGDTYYNEKF
KRWIYDTSKLASGVPARFSGS



KGKATLTSDKSSSTAYMQLSR
GSGTSYSLTIRSMEAEDAATY



LTSEDSAVYFCARDLRLGTFDY
YCQQGSSNPRTFGGGTKLELK



WGQGTTLTVSS






27-E7-D8-C7
SEQ ID NO: 71
SEQ ID NO: 72



EVQLQESGPELVRPGVSVKISC
QIVLSQSPAILSASPGEKVTMT



KGSGYTFTDYAMHWVKQSHA
CRASSSVSYMHWYQQKPGSSP



KSLEWIGVINTYSDNTNYNRKF
KPWIYATSNLASGVPARFSGS



KGKATMTVDKSSSTAYMELAR
GSGTSYSLTISRVEAEDAATYY



LTSEDSAIYYCARGLLLRSQLG
CQQWSSNPWTFGGGTKLEIK



VYFDYWGQGTTLTVSS






30-E2-G7-G7
SEQ ID NO: 79
SEQ ID NO: 80



EVQLQESGGGLVKPGGSLKLS
DIVMTQSQKFMSTSVGDRVSV



CAASGFTFSYYAMSWVRQTPE
TCKASQNVGTNVAWYHQRPG



KRLEWVATINGDGSHTYYPDS
QSPKPLIYSASYRYSGVPDRFT



VRGRFTISRDNAKNTLYLQVSS
GSGSGTDFTLTISNVQSEDLAE



LRSEDTAMYYCASLLQLGPFW
YFCQQYNNYPLTFGSGTKLEI



GQGTTLTVSS
K





5-D1-G6-D9
SEQ ID NO: 87
SEQ ID NO: 88



EVQLQESGAELVKPGASVKLS
DIQMTQTTSSLSASLGDRVTIS



CKTSGLTFSTNYISWLKQKPGQ
CRASQDISNYLNWYQQKPDGT



SLEWIAWIYGGNGGTSYNQRF
VKLLIYFTSRLHSGVPSRFSAS



TGKAQLTVDTSSSTAYMQFSSL
GSGTDYSLTISNLEQEDIATYF



TTEDSAIYYCTSHDYYGGPMD
CQQTNTLPWTFGGGTKLEIK



YWGQGTSVTVSS






3-C2-C3-E7
SEQ ID NO: 95
SEQ ID NO: 96



EVQLQQSGPELVKPGASVKISC
QIVLTQSPAIMSASPGEKVTMT



KTSGYTFTENTMHWVKQSHG
CSASSSVSYMHWYQQKSGTSP



KRLEWIGGINPNTGGTTYNQKF
KRWIYDTSKLASGVPARFSGS



KGKATLTVDKSSSTAYMELRS
GSGTSYSLTISSMEAEDAATYY



LTSEDSAVYYCARRGTNWEH
CQQWSSNPLTFGAGTKLELK



WYFDVWGAGTTVTVSS






11-G10-B4-
SEQ ID NO: 103
SEQ ID NO: 104


B11
DVQLQESGPGLVKPSQSLSLTC
DVVMTQTPLSLPVSLGDQASIS



TVTGYSITSDYAWNWIRQFPG
CRSSQSLVHSNGNTYLHWYLQ



NKLEWMGYISYSGSTSYNPSLK
KPGQSPKLLIYKVSNRFSGVPD



SRISITRDTSKNQFFLQLNSVTT
RFSGSGSGTDFTLKISRVEAED



EDTATYYCARGGPWFAYWGQ
LGVYFCSQSTHVPFTFGSGTKL



GTLVTVSA
EIK





16-C6-F7-F5
SEQ ID NO: 111
SEQ ID NO: 112



QIQLVQSGPEVKKPGETVKISC
DIVMTQTPLSLPVSLGDQASIS



KASGYTFTKYGINWVKQAPGE
CRSSQSLLHTNGDTYLHWYLQ



GLKWMGWIWTYTGKPTYGDD
KAGQPPKLLIYKVSNRFSGVP



FKGRFAFSLETSASTAYLQISDL
DRFSGSGSGTDFTLKISRVEAE



KIEDMATYFCARDDGYYYTM
DLGVYFCSQSTHIPWTFGGGT



NYWGQGTSVTVSS
KLEIK





22-E11-C3-F2
SEQ ID NO: 119
SEQ ID NO: 120



QIQLVQSGPELKRPGETVKISC
DVVMTQPPLSLPVSLGDQASIS



KASGYSFTNYGMNWVKQAPG
CRSSQSLIHSNGDTYLHWYLQ



KGLKWMGWINPYTGEPTYAD
KPGQSPKLLIYKVSIRFSGVPD



DFKGRFAMSLETSASAAYLQIN
RFSGSGSGTDFTLKISRVEAED



NLKNEDMATYFCGRDDGYHY
LGVYFCSQSTYVPWTFGGGTK



TMNYWGQGTSVTVSS
LEIK





24-C10-F9-G7
SEQ ID NO: 127
SEQ ID NO: 128



EVQLQESGPELVRPGVSVKISC
DIQMTQSPASLFASVGETVTIT



KGSGYTFTDHTMHWVKESHA
CRASEKIYSYLAWYFQKQGKS



QSLEWIGVISTYYGNTNYNQNF
PQFLVYNANALAEGVPSRFSG



KGKATLTVDKSSSTAYMELAG
SGSGTQFSLKINSLQPEDFGTY



LTSEDSAIYYCARASYGSGYGP
YCQHHYGTPVTFGAGSKLELK



YYWYFDVWGAGTTVTVSS






25-C8-D7-C5
SEQ ID NO: 135
SEQ ID NO: 136



EVQLQESGGGLVKPGGSLKFSC
QIVLTQSPAIMSASPGEKVTMT



AASGFTFSTYAMSWVRQTPEK
CRASSSVSFMHWYQQKSGTSP



RLEWVATISGGGIDTYYPDSVK
KRWIYETSKLASGVPDRFSGS



GRFTISRDNAKNTLYLQMNSLR
GSGTSYSLTISSMEAEDAATYY



SEDTAMYYCARQGSKGWGAM
CQQWSSNPLTFGAGTKLELK



DYWGQGTSVTVSS






4-D5-B9-B11
SEQ ID NO: 143
SEQ ID NO: 144



EIGGLVKPGGSLKFSCAASGFT
QIVLTQSPAIMSASPGEKVTMT



FSSYAMSWVRQTPEKRLEWVA
CRASSSVSFMHWYQQKSGTSP



TISGGGIYYPDSVKGRFTISRDN
KRWIYETSKLASGVPDRFSGS



AKNTLYLQMSSLRSEDTAMYY
GSGTSYSLTISSMEAEDAATYY



CARQGSKGWDAMDYWGQGT
CQQWSSNPLTFGAGTKLELK



SVTVSS






10-B9-D10-
SEQ ID NO: 151
SEQ ID NO: 152


A12
EVQLQESGPELVRPGVSVKISC
DIQMTQSPASLFASVGETVTIT



KGSGYTFTDYTMHWVKLSHA
CRASEKIYSYLAWYFQKQGKS



KSLEWIGVISTYYGNTNYNQKF
PQFLVYNANALAEGVPSRFSG



KGKATLTVDKSSSTAYMELAR
SGSGTQFSLKINSLQPEDFGTY



LTSEDSAIYYCARASYGSGYGP
YCQHHYGTPVTFGAGSKLELK



YYWYFDVWGAGTTVTVSS






15-G1-D1-E3
SEQ ID NO: 159
SEQ ID NO: 160



QVQLQQPGAELVKPGTSVKLS
QLVLTQSSSASFSLGASAKLTC



CKASGYTFTSYWIHWVKQRPG
TLSSQHSTYTIEWYQQQPLKPP



QGLEWIGMIHPKSGTVDYNEK
KYVMELKKDGSHRTGDGIPDR



FKSKATLTADKSSNTAYMQLS
FSGSSSGADRYLSISNIQPEDEA



SLTSEASVVYYCARGENYDYR
IYICGVGDTIKEQFVYVFGGGT



PQFVYWGQGTLVTVSA
KVTVL





8-B4-F5-E11
SEQ ID NO: 167
SEQ ID NO: 168



QVQLQQPGAELVKPGASVKLS
QAVVTQESALTTSPGETVTLT



CKASGDTFTSYWMHWVKQRP
CRSSTGAVTTSNFANWVQEKP



GQGLEWIGMIHPDSGTRNYNE
DHLFTGLIGGTNNRAPGVPAR



KVMSKATLNVDKSSSTAYLHL
FSGSLIGDKAALTITGAQTEDE



SSLTSEDSAVYYCSRSYGSRLA
AVYFCALWYTNHFIFGSGTKV



WFAYWGQGTLVTVSA
TVL





6-F3-G2-G1
SEQ ID NO: 175
SEQ ID NO: 176



QVQLQQPGAELVKPGASVKLS
QAVVTQESALTTSPGGTVILTC



CKASDYTFTNYWMHWVKQRP
RSSTGAVTTSNYANWVQEKP



GQGLEWIGMIHPNSGTTSYNEK
DHLFTGLIGGTSNRAPGVPVRF



FKNKATLTVDTSSATTYMHLSS
SGSLIGDKAALTITGAQTEDDA



LTSEDSAVYYCASHYGNSYSA
MYFCALWYSTHYVFGGGTKV



MDYWGQGTSVTVSS
TVL





9-B9-H11-G7
SEQ ID NO: 183
SEQ ID NO: 184



DVQLQESGPGLVKPSQSLSLTC
QAVVTQESALTTSPGGTVILTC



SVTGYSITSGYYWNWIRQFPGN
RSSTGAVTTSNYANWVQEKP



KLEWMVYISYDGTNNYNPSLK
DHLFTGLIGGTSNRAPGVPVRF



NRISITRDTSKNQFFLKLNSVTT
SGSLIGDKAALTITGAQTEDDA



EDTATYYCARGDSNSYYFDYW
MYFCALWYRTHYVFGGGTKV



GQGTTLTVSS
TVL





9-G12-D6-
SEQ ID NO: 191
SEQ ID NO: 192


A11
DVQLQVSGPGLVKPSQSLSLTC
QAVVTQESALTTSPGGTVILTC



SVAGYSITSDYYWNWIRQFPG
RSSTGAVTTSNYANWVQEKP



NKLEWMGYISYDGTNNYNPSL
DHLFTGLIGGTSNRAPGVPVRF



KNRISITRDTSKGQFFLKFNSVT
SGSLIGDKAALTITGAQTEDDA



TEDTATYYCARGKDGSYYFDY
MYFCALWYRTHYVFGGGTM



WGQGTTLTVSS
VTVL





13-A8-C4-G1
SEQ ID NO: 199
SEQ ID NO: 200



QVQLQQPGAELVKPGASMKLS
QAVVTQESALTTSPGETVTLT



CKASGYIFTSNWMHWVKQRP
CRSSTGAVTTSNYANWVQEKP



GQGLEWIGMIHPNSGTTSYNEK
DHLFTGLIGGTNNRAPGVPAR



FKNKAKLTVDKSSSTAYVQLSS
FSGSLIGDKAALTITGAQTEDE



LTSEDSAVYYCAGPTTTRRFYP
AIYFCALWYSNHFIFGSGTKVT



MDYWGQGTSVTVSS
VL





15-C8-B5-G7
SEQ ID NO: 207
SEQ ID NO: 208



QVQLQQPGAELVKPGASVKLS
QAVVTQESALTTSPGETVTLT



CKASDYTFTSHWMHWVKQRP
CRSSTGAVTTSNYANWVQEKP



GQGLEWIGMIHPNSGTTHYNE
AHLFTGLIGGTNNRAPGVPAR



NFKNKATLTVDNSSSTAYMQL
FSGSLIGDKAALTITGAQTEDE



SSLTSEDSAVYYCAWGSSNSYF
AIYFCALWFSNHLVFGGGTKL



YAMAYWGQGTSVTVSS
TVL





28-G2-E6-B10
SEQ ID NO: 215
SEQ ID NO: 216



QVQLQQPGAELVKPGASVKLS
QAVVTQESALTTSPGGTVILTC



CKASGYTFTSYWMHWVKQRP
RSSTGAVTTSNYASWVQEKPD



GQGLEWIGMIHPNSDTTDYNE
HLFTGLIGGTSNRAPGVPVRFS



KFKTKATLTVDKSSSTAYMQL
GSLIGDKAALTITGAQTEDDA



SSLTSEDSAVFYCARGGLGPHY
MYFCALWYSPHYVFGGGTKV



FVYWGQGTTLTVSS
TVL





3-G7-D8-D3
SEQ ID NO: 223
SEQ ID NO: 224



QVQLQQSGAELARPGTSVKLS
QIVLTQSPAIMSASPGEKVTMT



CKASGYTFTTYWIQWVKQRPG
CSASSRINYMHWYQQKPGTSP



QGLEWIGAIYPGDGDTRYTQK
IIWIYDTSKLASGVPARFSGSG



FKGKATLTADKSSSTAYMQLS
SGTSYSLTISSMEAEDAATYYC



TLASEDSAVYYCARPYDGYYI
HQRSSYPFTFGSGTKLEIK



DYPMDSWGQGTSVTVSS






14-E7-G9-D4
SEQ ID NO: 231
SEQ ID NO: 232



EVQLQQSGPELVKPGASVKMS
QIVLSQSPAILSASPGEKVTMT



CKASGYTFTNYIMHWVKQKPG
CRASSSVSYMHWYQQKPGSSP



QGLEWIGYINPYNDGIKYNEKF
KPWIYATSNLASGVPARFSGS



KGKATLTSDKSSSTAYMELSSL
GSGTSYSLTISRMEAEDAATY



TSEDSAVYYCTRWGNYVFYYT
YCQQWSGNPPLTFGAGTKLEL



MDYWGQGTSVTVSS
K





20-C5-D7-D3
SEQ ID NO: 239
SEQ ID NO: 240



EVQLVESGGDLVKPGGSLKLS
DIQMTQSPASLSASVGETVTIT



CAASGFTFRSYGMSWVRQTPD
CRASENIYSYLAWYQQKQGKS



KRLEWVATISGGGNYTYYPDS
PQLLVYNAKTLAEGVPSRFSG



VKGRFTISRDNAKNTLYLQMSS
SGSGTQFSLKINSLQPEDFGNF



LKSEDTAMYYCARHEGLPLDY
YCQHHYGTPTWTFGGGTKLEI



WGQGTTLTVSS
K





8-C3-E3-F3
SEQ ID NO: 247
SEQ ID NO: 248



EVQLVESGGGLVQPGGSLKLS
DIVMTQAAFSNPVTLGTSASIS



CAASGFTFSNYGLSWVRLTPD
CRSSKSLLHSNGITYLYWYLQ



KRLEVVATIGSYGGNTYYPDS
KPGQSPQLLIYQMSNLASGVP



VKGRFTISRDNAKNTLYLQMSS
DRESSSGSETDFTLRISRVEAE



LKSEDTAIYYCARDIYYGNSEA
DVGVYYCAQNLELPWTFGGG



WFAYWGQGTLVTVSA
TKLEIK





2-A7-B10-A3
SEQ ID NO: 255
SEQ ID NO: 256



QVQLQQSGAELVRPGVSVKISC
DIQMTQTTSSLSASLGDRVTIS



KGSGYTFTDYAMHWVKQSHA
CRASQDISNYLNWYQQKPDGT



KSLEWIGVINTNYVNTSYNQKF
VKLLIYYTSRLHSGVPSRFSGS



KGKATMTVDKSSSTAFMELAR
GSGTDYSLTISNLEQEDIATYF



LTSEDSAIYYCARGGKYGNYV
CQQGNTLPYTFGGGTKLEIK



FFFAYWGQGTLVTVSA






26-D2-D6-
SEQ ID NO: 263
SEQ ID NO: 264


B12
QIQLVQSGPELKKPGETVKISC
DVVMTQTPLSLPVSLGDQASIS



KASGYIFRNYGMNWVKQAPG
CRSSQSLVHSNGHTYLHWYLQ



KGLKWMGWINSYTGKPTYVD
KPGQSPKLLIYKVSNRFSGVPD



DFKGRFAFSLETSASTAYLQIN
RFSGSGSGTDFTLKISRVEAED



NLKNEDMATYFCARDDGYWY
LGVYFCSQSTHVPWTFGGGTK



TMDYWGQGTSVTVSS
LEIK





11-C12-F4-F6
SEQ ID NO: 271
SEQ ID NO: 272



QIQLVQSGPELKKPGETVKISC
DVVMTQTPPSLPVSLGDQASIP



KASGYTFRNFGMNWVKQGPG
CRSSQSLVHSNGITYLHWYLQ



KGLKWMGWINPYTGEPTYVG
KPGQSPKLLIYKVSNRFSGVPD



DFKGRFAFSLETSASTAYLQIN
RFSGSGSGTDFTLKISRVEAED



NLKNEDMATYFCARDDGYWY
LGVYFCSQSTHVPWTFGGGTK



TMDYWGQGTSVTVSS
LEIK





16-G3-D10-
SEQ ID NO: 279
SEQ ID NO: 280


C10
QIQLVQSGPELKKPGETVKISC
DVVMTQTPPSLPVSLGDQASIP



KASGYTFRNYGMNWVKQGPG
CRSSQSLVHSNGITYLHWYLQ



KDLKWMGWINPYTGEPTYIGD
KPGQSPKLLIYKVSNRFSGVPD



FKGRFAFSLETSANSAYLQINN
RFSGSGSGTDFTLKISRVEAED



LNNEDMATYFCARDDGYWYT
LGVYFCSQSTHVPWTFGGGTK



MDYWGQGTSVTVSS
LEIK





27-F8-E10-
SEQ ID NO: 287
SEQ ID NO: 288


E11
EVQLQQSGPELVKPGASVKISC
QIVLTQSPAIMSASPGEKVTMT



KTSGYTFTEYAMHWVKQSHG
CSASSSVSYMHWYQQKSGTSP



KILEWIGGINPNIGGTTYNQKF
KRWIYDTSRVASGVPARFSGS



KDKATLTVDKSSSTASMELRSL
GSGTSYSLTISSMEAEDAATYY



TSEDSAVYYCARFLVPSTEGFT
CQQWSSNPLTFGAGTKLELK



YWGQGTLVTVSA






7-E1-F8-F6
SEQ ID NO: 295
SEQ ID NO: 296



QVQLQQSGPELVKPGASVQMS
DVVMTQTPLSLPVSLGDQASIS



CKASGYTFTDYVISWVNQRTG
CRSTQSLVHSNGVTYLHWYL



QGLEWIGEIYPRSGNTYYNEKF
QKPGQSPKLLIYKVSNRFSGVP



KGKATLTADKSSNTAYMQLSS
DRFSGSGSGTDFTLKISRVEAE



LTSEDSAVYFCARFDIAYSFDY
DLGVYFCSQGTHVPWTFGGG



WGQGTTLTVSS
TKLEIK





25-D3-G4-C6
SEQ ID NO: 303
SEQ ID NO: 304



EIQLQQTGPELVKPGASVKISC
DVVMTQTPLSLPVSLGDQASIS



KASGYSFTDYIILWVKQSHGMS
CRSSQSLVHSNGNTYLHWYLQ



LEWIGNINPYYNSTYYNLKFKG
KPGQSPKLLIYKVSNRFSGVPD



KATLTVDKSSSTAYMQLDSLTS
RFSGSGSGTDFTLKISRVETED



EDSAVYYCARDSFDWYFGVW
LGIYFCSQSTHVPPLTFGAGTK



GAGTTVTVSS
LELK





13-E4-G9-A4
SEQ ID NO: 311
SEQ ID NO: 312



EVMLVESGGGLVKPGGSLKFS
QIVLTQSPPIMSASPGERVTMT



CAASGFTFITYAMSWVRQTPE
CRASSRVSFMHWYQQKSGTSP



KRLEWVATISGGGIDTYYPDSV
RRWIYETSKLASGVPDRFSGS



KGRFTISRDNAKNTLYLQVNSL
VSGTSYSLTISSMEAEDAATYY



RSEDTAMYYCTRQGSQGWGA
CQQWSSNPLTFGAGTKLELK



MDYWGQGTSVTVSS






20-A2-D10-
SEQ ID NO: 319
SEQ ID NO: 320


G8
QVQLQQSGPELVRPGVSVKISC
DIQMTQSPASLFASVGETVTIT



KGSGYTFTDYTMHWVKESHA
CRASEKIYSYLAWYFQKQGKS



QSLEWIGVISTYYGNTNYNQNF
PQFLVYNANALAEGVPSRFSG



KGKATLTVDKSSSTAYMELAG
SGSGTQFSLKIKSLQPEDFGTY



LTSEDSAIYYCARASYGSGYGP
YCQHHYGSPVTFGAGSKLELK



YYWYFDVWGAGTTVTVSS






3-F2-E7-F9
SEQ ID NO: 327
SEQ ID NO: 328



QVQLQQSGPELVRPGVSVKISC
DIQMTQSPASLFASVGETVTIT



KGSGYTFTDYTMHWVKESHA
CRASEKIYSYLAWYFQKQGKS



KSLEWIGVISTYYGNTNYNQKF
PQFLVYNANALAEGVPSRFSG



KGKATLTVDKSSSTAYMELAG
SGSGTQFSLKINSLQPEDFGTY



LTSEDSAIYYCARASYGSGYGP
YCQHHYGTPVTFGAGSKLELK



YYWYFDVWGAGTTVTVSS






6-D8-E7-A11
SEQ ID NO: 335
SEQ ID NO: 336



QVHLQQPGAELVKPGASVKLS
QAVVTQESALTTSPGGTVILTC



CKASGYTFTNYWMHWVKRRP
RSSTGAVTTSNFANWVQEKPD



GQGLEWIGMIHPNSGTTSFNEK
HLFTGLIGGTSNRAPGVPVRFS



FKSKATLTVDKSSSTAYMQLSS
GSLIGDKAALTITGAQTEDDA



LTSEDSAVYYCAGYYGSSFSW
MYFCALWYSTHYVFGGGTKV



FTYWGQGTLVTVSA
TVL





21-B3-B1-H5
SEQ ID NO: 343
SEQ ID NO: 344



QIQLVQSGPELKKPGETVKISC
DVVMTQTPLSLPVSLGDQASIS



KASGYIFRNYGMNWVKQAPG
CRSSQSLVHSNGHTYLHWYLQ



KGLKWMGWINSYTGKPTYVD
KPGQSPKLLIYKVSNRFSGVPD



DFKGRFAFSLETSASTAYLQIN
RFSGSGSGTDFTLKISRVEAED



NLKNEDMATYFCARDDGYWY
LGVYFCSQSTHVPWTFGGGTK



TMDYWGQGTSVTVSS
LEIK









CDRs are known to be responsible for antigen binding, however, it has been found that not all of the 6 CDRs are indispensable or unchangeable. In other words, it is possible to replace or change or modify one or more CDRs in anti-CD276 antibody 9-E8-F9-C10, 10-G6-C4-B2, 18-F9-D8-G7, 9-G2-H6-E4, 20-F8-B5-G2, 30-C7-C11-D4, 23-F10-G4-F11, 6-H11-G5-D8, 27-E7-D8-C7, 30-E2-G7-G7, 5-D1-G6-D9, 3-C2-C3-E7, 11-G10-B4-B11, 16-C6-F7-F5, 22-E11-C3-F2, 24-C10-F9-G7, 25-C8-D7-C5, 4-D5-B9-B11, 10-B9-D10-A12, 15-G1-D1-E3, 8-B4-F5-E11, 6-F3-G2-G1, 9-B9-H11-G7, 9-G12-D6-A11, 13-A8-C4-G1, 15-C8-B5-G7, 28-G2-E6-B10, 3-G7-D8-D3, 14-E7-G9-D4, 20-C5-D7-D3, 8-C3-E3-F3, 2-A7-B10-A3, 26-D2-D6-B12, 11-C12-F4-F6, 16-G3-D10-C10, 27-F8-E10-E11, 7-E1-F8-F6, 25-D3-G4-C6, 13-E4-G9-A4, 20-A2-D10-G8, 3-F2-E7-F9, 6-D8-E7-A11, and 21-B3-B1-H5, yet substantially retain the specific binding affinity to CD276.


In certain embodiments, the anti-CD276 antibodies and the antigen-binding fragments provided herein comprise a heavy chain CDR3 sequence of one of the anti-CD276 antibodies 9-E8-F9-C10, 10-G6-C4-B2, 18-F9-D8-G7, 9-G2-H6-E4, 20-F8-B5-G2, 30-C7-C11-D4, 23-F10-G4-F11, 6-H11-G5-D8, 27-E7-D8-C7, 30-E2-G7-G7, 5-D1-G6-D9, 3-C2-C3-E7, 11-G10-B4-B11, 16-C6-F7-F5, 22-E11-C3-F2, 24-C10-F9-G7, 25-C8-D7-C5, 4-D5-B9-B11, 10-B9-D10-A12, 15-G1-D1-E3, 8-B4-F5-E11, 6-F3-G2-G1, 9-B9-H11-G7, 9-G12-D6-A11, 13-A8-C4-G1, 15-C8-B5-G7, 28-G2-E6-B10, 3-G7-D8-D3, 14-E7-G9-D4, 20-C5-D7-D3, 8-C3-E3-F3, 2-A7-B10-A3, 26-D2-D6-B12, 11-C12-F4-F6, 16-G3-D10-C10, 27-F8-E10-E11, 7-E1-F8-F6, 25-D3-G4-C6, 13-E4-G9-A4, 20-A2-D10-G8, 3-F2-E7-F9, 6-D8-E7-A11, and 21-B3-B1-H5. In certain embodiments, the anti-CD276 antibodies and the antigen-binding fragments provided herein comprise a heavy chain CDR3 sequence selected from the group consisting of SEQ ID NOs: 3, 11, 19, 27, 35, 43, 51, 59, 67, 75, 83, 91, 99, 107, 115, 123, 131, 139, 147, 155, 163, 171, 179, 187, 195, 203, 211, 219, 227, 235, 243, 251, 259, 267, 275, 283, 291, 299, 307, 315, 323, 331, and 339. Heavy chain CDR3 regions are located at the center of the antigen-binding site, and therefore are believed to make the most contact with antigen and provide the most free energy to the affinity of antibody to antigen. It is also believed that the heavy chain CDR3 is by far the most diverse CDR of the antigen-binding site in terms of length, amino acid composition and conformation by multiple diversification mechanisms (Tonegawa S. Nature. 302:575-81). The diversity in the heavy chain CDR3 is sufficient to produce most antibody specificities (Xu J L, Davis M M. Immunity. 13:37-45) as well as desirable antigen-binding affinity (Schier R, etc. J Mol Biol. 263:551-67).


In certain embodiments, the antibodies and/or antigen-binding fragments thereof provided herein comprise suitable framework region (FR) sequences, as long as the antibodies and/or antigen-binding fragments thereof can specifically bind to CD276. The CDR sequences provided in Table 1 are obtained from mouse antibodies, but they can be grafted to any suitable FR sequences of any suitable species such as mouse, human, rat, rabbit, among others, using suitable methods known in the art such as recombinant techniques.


In certain embodiments, the antibodies and/or antigen-binding fragments thereof provided herein are PTM optimized. As used herein, PTM optimization refers to post-translation modification, aiming at avoiding potential aggregation, activity loss or other risk. Exemplary PTM optimized antibody and/or antigen-binding fragments thereof includes mVH5-mVL4-10 and mVH-mVL1-30, derived from 10-G6-C4-B2 and 30-C7-C11-D4, respectively. The variable region sequences of mVH5-mVL4-10 and mVH-mVL1-30 are shown in Table 3, wherein all the CDR regions are underlined.









TABLE 3







CDR sequences and variable region sequences of the anti-CD276


antibodies with PTM optimization











Clone
VH

VL













mVH5-mVL4-
SEQ ID NO: 347
SEQ ID NO: 348


10
EVQLVESGGGLVQPGGSLRLSC
DIVMTQSPSSLTVTAGEKVTM



ATSGFTLSDYYMSWVRQPPGK
SCKSSQSLLNAINQKNFLTWY



APEWLGFMRNKANAYTTEYSA
QQKPGQPPKLLIYWASTRESG



SVRGRFTISRDTSQSIIYLQMNT
VPDRFTGSGSGTDFTLTISSVQ



LRAEDGATYYCVRDREGRPFA
AEDLAIYYCQNDYTYPLTFGT




YWGQGTLVTVSA

GTKLELK












CDR1
SEQ ID NO: 9
CDR1
SEQ ID NO: 376




GFTLSDYY

QSLLNAINQKNF



CDR2
SEQ ID NO: 374
CDR2
SEQ ID NO: 13




MRNKANAYTT

WAS



CDR3
SEQ ID NO: 375
CDR3
SEQ ID NO: 14




VRDREGRPFAY

QNDYTYPLT












mVH-mVL1-
SEQ ID NO: 349
SEQ ID NO: 350


30
EVQLVESGPGLVKPSQSLSLTC
DIVMTQSPSSLAMSVGQKVTL



TVTGYSITSDYAWNWIRQFPG
SCKSSQSLLQSSTQKNYLAWY



NKLEWMGYISHSGSTSYNPSLK
QQKPGQSPKLLVYFASTRDSG



SRISITRDTSKNQFFLQLNSVTT
VPDRFIGSGSGTEFTLTISSVQA



EDTATYYCARSLGRRWYFDV
EDLADYFCQQHYIIPFTFGAGT



WGAGTTVTVSS
KLEIK












CDR1
SEQ ID NO: 41
CDR1
SEQ ID NO: 377




GYSITSDYA

QSLLQSSTQKNY



CDR2
SEQ ID NO: 42
CDR2
SEQ ID NO: 45




SHSGST

FAS



CDR3
SEQ ID NO: 43
CDR3
SEQ ID NO: 46




ARSLGRRWYFDV

QQHYIIPFT









In certain embodiments, the antibodies and/or antigen-binding fragments thereof provided herein are humanized. A humanized antibody or antigen-binding fragment is desirable in its reduced immunogenicity in human. A humanized antibody is chimeric in its variable regions, as non-human CDR sequences are grafted to human or substantially human FR sequences. Humanization of an antibody or antigen-binding fragment can be essentially performed by substituting the non-human (such as murine) CDR genes for the corresponding human CDR genes in a human immunoglobulin gene (see, for example, Jones et al. (1986) Nature 321:522-525; Riechmann et al. (1988) Nature 332:323-327; Verhoeyen et al. (1988) Science 239:1534-1536).


Suitable human heavy chain and light chain variable domains can be selected to achieve this purpose using methods known in the art. In an illustrative example, “best-fit” approach can be used, where a non-human (e.g. rodent) antibody variable domain sequence is screened or BLASTed against a database of known human variable domain sequences, and the human sequence closest to the non-human query sequence is identified and used as the human scaffold for grafting the non-human CDR sequences (see, for example, Sims et al, (1993) J. Immunol. 151:2296; Chothia et al. (1987) J. Mot. Biol. 196:901). Alternatively, a framework derived from the consensus sequence of all human antibodies may be used for the grafting of the non-human CDRs (see, for example, Carter et al. (1992) Proc. Natl. Acad. Sci. USA, 89:4285; Presta et al. (1993) J. Immunol., 151:2623). In certain embodiments, the humanized antibodies or antigen-binding fragments provided herein are composed of substantially all human sequences except for the CDR sequences which are non-human. In some embodiments, the variable region FRs, and constant regions if present, are entirely or substantially from human immunoglobulin sequences. The human FR sequences and human constant region sequences may be derived different human immunoglobulin genes, for example, FR sequences derived from one human antibody and constant region from another human antibody.


Table 4 below shows the heavy chain and light chain variable region amino acid sequences of humanized antibodies for 10-G6-C4-B2 and 30-C7-C11-D4, which are designated as hVH2-hVL1-10, hVH3-hVL3-10, hVH4-hVL1-10, hVH4-hVL2-10, hVH5-hVL1-10, hVH5-hVL3-10, 10-G6-C4-B2_hVH2-VL1_PTM, 10-G6-C4-B2_hVH3-VL3_PTM, 10-G6-C4-B2_hVH4-VL1_PTM, 10-G6-C4-B2_hVH4-VL2_PTM, 10-G6-C4-B2_hVH5-VL1_PTM, 10-G6-C4-B2 hVH5-VL3_PTM, hVH1-hVL5-30, hVH2-hVL1-30, hVH3-hVL2-30, hVH3-hVL5-30, hVH4-hVL2-30, hVH4-hVL5-30, 30-C7-C11-D4_hVH1-hVL5_PTM, 30-C7-C11-D4_hVH2-hVL1_PTM, 30-C7-C11-D4_hVH3-hVL2_PTM, 30-C7-C11-D4_hVH3-hVL5_PTM, 30-C7-C11-D4_hVH4-hVL2_PTM and 30-C7-C11-D4 hVH4-hVL5 PTM, wherein all the CDR regions are underlined.









TABLE 4







Variable region amino acid sequences of the umanized


antibodies









Antibody
VH
VL





hVH2-
SEQ ID NO: 351
SEQ ID NO: 352


hVL1-10
EVQLVESGGGLVQPGGSLRLS
DIVMTQSPDSLAVSLGERATI



CATSGFTLSDYYMSWVRQAP
NCKSSQSLLNSINQKNFLTW



GKGLEWVSFMRNKANGYTT
YQQKPGQPPKLLIYWASTRE



EYSASVRGRFTISRDTSKSTIY
SGVPDRFSGSGSGTDFTLTIS



LQMNSLRAEDTAVYYCVRDR
SLQAEDLAVYYCQNDYTYP




DGRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






hVH3-
SEQ ID NO: 353
SEQ ID NO: 354


hVL3-10
EVQLVESGGGLVQPGGSLRLS
DIQMTQSPSSLSASVGDRVTI



CATSGFTLSDYYMSWVRQAP
TCKSSQSLLNSINQKNFLTW



GKGLEWVGFMRNKANGYTT
YQQKPGKAPKLLIYWASTRE



EYSASVRGRFTISRDTSKSSIY
SGVPSRFSGSGSGTDFTLTIS



LQMNSLKTEDTAVYYCVRDR
SLQPEDLATYYCQNDYTYPL




DGRPFAYWGQGTLVTVSS


TFGQGTKLEIK






hVH4-
SEQ ID NO: 355
SEQ ID NO: 352


hVL1-10
EVQLVESGGGLIQPGGSLRLS
DIVMTQSPDSLAVSLGERATI



CATSGFTLSDYYMSWVRQPP
NCKSSQSLLNSINQKNFLTW



GKGLEWVSFMRNKANGYTT
YQQKPGQPPKLLIYWASTRE



EYSASVRGRFTISRDTSKSTIY
SGVPDRFSGSGSGTDFTLTIS



LQMNSLRAEDTAVYYCVRDR
SLQAEDLAVYYCQNDYTYP




DGRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






hVH4-
SEQ ID NO: 355
SEQ ID NO: 356


hVL2-10
EVQLVESGGGLIQPGGSLRLS
DIVMTQSPLSLPVTPGEPASI



CATSGFTLSDYYMSWVRQPP
SCKSSQSLLNSINQKNFLTW



GKGLEWVSFMRNKANGYTT
YLQKPGQSPQLLIYWASTRE



EYSASVRGRFTISRDTSKSTIY
SGVPDRFSGSGSGTDFTLKIS



LQMNSLRAEDTAVYYCVRDR
RVEAEDLGVYYCQNDYTYP




DGRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






hVH5-
SEQ ID NO: 357
SEQ ID NO: 352


hVL1-10
EVQLVESGGGLVQPGRSLRLS
DIVMTQSPDSLAVSLGERATI



CTTSGFTLSDYYMSWVRQAP
NCKSSQSLLNSINQKNFLTW



GKGLEWVGFMRNKANGYTT
YQQKPGQPPKLLIYWASTRE



EYSASVRGRFTISRDTSKSIIYL
SGVPDRFSGSGSGTDFTLTIS



QMNSLKTEDTAVYYCVRDRD
SLQAEDLAVYYCQNDYTYP




GRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






hVH5-
SEQ ID NO: 357
SEQ ID NO: 354


hVL3-10
EVQLVESGGGLVQPGRSLRLS
DIQMTQSPSSLSASVGDRVTI



CTTSGFTLSDYYMSWVRQAP
TCKSSQSLLNSINQKNFLTW



GKGLEWVGFMRNKANGYTT
YQQKPGKAPKLLIYWASTRE



EYSASVRGRFTISRDTSKSIIYL
SGVPSRFSGSGSGTDFTLTIS



QMNSLKTEDTAVYYCVRDRD
SLQPEDLATYYCQNDYTYPL




GRPFAYWGQGTLVTVSS


TFGQGTKLEIK






10-G6-C4-
SEQ ID NO: 358
SEQ ID NO: 359


B2_hVH2-
EVQLVESGGGLVQPGGSLRLS
DIVMTQSPDSLAVSLGERATI


VL1_PTM
CATSGFTLSDYYMSWVRQAP
NCKSSQSLLNAINQKNFLTW



GKGLEWVSFMRNKANAYTT
YQQKPGQPPKLLIYWASTRE



EYSASVRGRFTISRDTSKSTIY
SGVPDRFSGSGSGTDFTLTIS



LQMNSLRAEDTAVYYCVRDR
SLQAEDLAVYYCQNDYTYP




EGRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






10-G6-C4-
SEQ ID NO: 360
SEQ ID NO: 361


B2_hVH3-
EVQLVESGGGLVQPGGSLRLS
DIQMTQSPSSLSASVGDRVTI


VL3_PTM
CATSGFTLSDYYMSWVRQAP
TCKSSQSLLNAINQKNFLTW



GKGLEWVGFMRNKANAYTT
YQQKPGKAPKLLIYWASTRE



EYSASVRGRFTISRDTSKSSIY
SGVPSRFSGSGSGTDFTLTIS



LQMNSLKTEDTAVYYCVRDR
SLQPEDLATYYCQNDYTYPL




EGRPFAYWGQGTLVTVSS


TFGQGTKLEIK






10-G6-C4-
SEQ ID NO: 362
SEQ ID NO: 359


B2_hVH4-
EVQLVESGGGLIQPGGSLRLS
DIVMTQSPDSLAVSLGERATI


VL1_PTM
CATSGFTLSDYYMSWVRQPP
NCKSSQSLLNAINQKNFLTW



GKGLEWVSFMRNKANAYTT
YQQKPGQPPKLLIYWASTRE



EYSASVRGRFTISRDTSKSTIY
SGVPDRFSGSGSGTDFTLTIS



LQMNSLRAEDTAVYYCVRDR
SLQAEDLAVYYCQNDYTYP




EGRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






10-G6-C4-
SEQ ID NO: 362
SEQ ID NO: 363


B2_hVH4-
EVQLVESGGGLIQPGGSLRLS
DIVMTQSPLSLPVTPGEPASI


VL2_PTM
CATSGFTLSDYYMSWVRQPP
SCKSSQSLLNAINQKNFLTW



GKGLEWVSFMRNKANAYTT
YLQKPGQSPQLLIYWASTRE



EYSASVRGRFTISRDTSKSTIY
SGVPDRFSGSGSGTDFTLKIS



LQMNSLRAEDTAVYYCVRDR
RVEAEDLGVYYCQNDYTYP




EGRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






10-G6-C4-
SEQ ID NO: 364
SEQ ID NO: 359


B2_hVH5-
EVQLVESGGGLVQPGRSLRLS
DIVMTQSPDSLAVSLGERATI


VL1_PTM
CTTSGFTLSDYYMSWVRQAP
NCKSSQSLLNAINQKNFLTW



GKGLEWVGFMRNKANAYTT
YQQKPGQPPKLLIYWASTRE



EYSASVRGRFTISRDTSKSIIYL
SGVPDRFSGSGSGTDFTLTIS



QMNSLKTEDTAVYYCVRDRE
SLQAEDLAVYYCQNDYTYP




GRPFAYWGQGTLVTVSS


LTFGQGTKLEIK






10-G6-C4-
SEQ ID NO: 364
SEQ ID NO: 361


B2_hVH5-
EVQLVESGGGLVQPGRSLRLS
DIQMTQSPSSLSASVGDRVTI


VL3_PTM
CTTSGFTLSDYYMSWVRQAP
TCKSSQSLLNAINQKNFLTW



GKGLEWVGFMRNKANAYTT
YQQKPGKAPKLLIYWASTRE



EYSASVRGRFTISRDTSKSIIYL
SGVPSRFSGSGSGTDFTLTIS



QMNSLKTEDTAVYYCVRDRE
SLQPEDLATYYCQNDYTYPL




GRPFAYWGQGTLVTVSS


TFGQGTKLEIK






hVH1-
SEQ ID NO: 365
SEQ ID NO: 366


hVL5-30
QVQLQESGPGLVKPSQTLSLT
DIVMTQSPLSLPVTPGEPASI



CTVSGYSITSDYAWNWIRQHP
SCKSSQSLLNSSTQKNYLAW



GKGLEWIGYISHSGSTSYNPS
YLQKPGQSPQLLIYFASTRDS



LKSRVTISRDTSKNQFSLKLSS
GVPDRFSGSGSGTDFTLKISR



VTAADTAVYYCARSLGRRW
VEAEDLGVYFCQQHYIIPFTF




YFDVWGQGTTVTVSS

GQGTKLEIK





hVH2-
SEQ ID NO: 367
SEQ ID NO: 368


hVL1-30
QVQLQESGPGLVKPSETLSLT
DIQMTQSPSSLSASVGDRVTI



CTVSGYSITSDYAWNWIRQPP
TCKSSQSLLNSSTQKNYLAW



GKGLEWIGYISHSGSTSYNPS
YQQKPGKAPKLLIYFASTRD



LKSRVTISRDTSKNQFSLKLSS
SGVPSRFSGSGSGTDFTLTIS



VTAADTAVYYCARSLGRRW
SLQPEDLATYFCQQHYIIPFT




YFDVWGQGTTVTVSS

FGQGTKLEIK





hVH3-
SEQ ID NO: 367
SEQ ID NO: 369


hVL2-30
QVQLQESGPGLVKPSETLSLT
DIVMTQSPDSLAVSLGERATI



CTVSGYSITSDYAWNWIRQPP
NCKSSQSLLNSSTQKNYLA



GKGLEWIGYISHSGSTSYNPS
WYQQKPGQPPKLLIYFASTR



LKSRVTISRDTSKNQFSLKLSS
DSGVPDRFSGSGSGTDFTLTI



VTAADTAVYYCARSLGRRW
SSLQAEDLAVYFCQQHYIIPF




YFDVWGQGTTVTVSS


TFGQGTKLEIK






hVH3-
SEQ ID NO: 367
SEQ ID NO: 366


hVL5-30
QVQLQESGPGLVKPSETLSLT
DIVMTQSPLSLPVTPGEPASI



CTVSGYSITSDYAWNWIRQPP
SCKSSQSLLNSSTQKNYLAW



GKGLEWIGYISHSGSTSYNPS
YLQKPGQSPQLLIYFASTRDS



LKSRVTISRDTSKNQFSLKLSS
GVPDRFSGSGSGTDFTLKISR



VTAADTAVYYCARSLGRRW
VEAEDLGVYFCQQHYIIPFTF




YFDVWGQGTTVTVSS

GQGTKLEIK





hVH4-
SEQ ID NO: 370
SEQ ID NO: 369


hVL2-30
QVQLQESGPGLVKPSQTLSLT
DIVMTQSPDSLAVSLGERATI



CAVYGYSITSDYAWNWIRQP
NCKSSQSLLNSSTQKNYLA



PGKGLEWIGYISHSGSTSYNPS
WYQQKPGQPPKLLIYFASTR



LKSRVTISRDTSKNQFSLKLSS
DSGVPDRFSGSGSGTDFTLTI



VTAADTAVYYCARSLGRRW
SSLQAEDLAVYFCQQHYIIPF




YFDVWGQGTTVTVSS


TFGQGTKLEIK






hVH4-
SEQ ID NO: 370
SEQ ID NO: 366


hVL5-30
QVQLQESGPGLVKPSQTLSLT
DIVMTQSPLSLPVTPGEPASI



CAVYGYSITSDYAWNWIRQP
SCKSSQSLLNSSTQKNYLAW



PGKGLEWIGYISHSGSTSYNPS
YLQKPGQSPQLLIYFASTRDS



LKSRVTISRDTSKNQFSLKLSS
GVPDRFSGSGSGTDFTLKISR



VTAADTAVYYCARSLGRRW
VEAEDLGVYFCQQHYIIPFTF




YFDVWGQGTTVTVSS

GQGTKLEIK





30-C7-C11-
SEQ ID NO: 365
SEQ ID NO: 371


D4_hVH1-
QVQLQESGPGLVKPSQTLSLT
DIVMTQSPLSLPVTPGEPASI


hVL5_PTM
CTVSGYSITSDYAWNWIRQHP
SCKSSQSLLQSSTQKNYLAW



GKGLEWIGYISHSGSTSYNPS
YLQKPGQSPQLLIYFASTRDS



LKSRVTISRDTSKNQFSLKLSS
GVPDRFSGSGSGTDFTLKISR



VTAADTAVYYCARSLGRRW
VEAEDLGVYFCQQHYIIPFTF




YFDVWGQGTTVTVSS

GQGTKLEIK





30-C7-C11-
SEQ ID NO: 367
SEQ ID NO: 372


D4_hVH2-
QVQLQESGPGLVKPSETLSLT
DIQMTQSPSSLSASVGDRVTI


hVL1_PTM
CTVSGYSITSDYAWNWIRQPP
TCKSSQSLLQSSTQKNYLAW



GKGLEWIGYISHSGSTSYNPS
YQQKPGKAPKLLIYFASTRD



LKSRVTISRDTSKNQFSLKLSS
SGVPSRFSGSGSGTDFTLTIS



VTAADTAVYYCARSLGRRW
SLQPEDLATYFCQQHYIIPFT




YFDVWGQGTTVTVSS

FGQGTKLEIK





30-C7-C11-
SEQ ID NO: 367
SEQ ID NO: 373


D4_hVH3-
QVQLQESGPGLVKPSETLSLT
DIVMTQSPDSLAVSLGERATI


hVL2_PTM
CTVSGYSITSDYAWNWIRQPP
NCKSSQSLLQSSTQKNYLA



GKGLEWIGYISHSGSTSYNPS
WYQQKPGQPPKLLIYFASTR



LKSRVTISRDTSKNQFSLKLSS
DSGVPDRFSGSGSGTDFTLTI



VTAADTAVYYCARSLGRRW
SSLQAEDLAVYFCQQHYIIPF




YFDVWGQGTTVTVSS


TFGQGTKLEIK






30-C7-C11-
SEQ ID NO: 367
SEQ ID NO: 371


D4_hVH3-
QVQLQESGPGLVKPSETLSLT
DIVMTQSPLSLPVTPGEPASI


hVL5_PTM
CTVSGYSITSDYAWNWIRQPP
SCKSSQSLLQSSTQKNYLAW



GKGLEWIGYISHSGSTSYNPS
YLQKPGQSPQLLIYFASTRDS



LKSRVTISRDTSKNQFSLKLSS
GVPDRFSGSGSGTDFTLKISR



VTAADTAVYYCARSLGRRW
VEAEDLGVYFCQQHYIIPFTF




YFDVWGQGTTVTVSS

GQGTKLEIK





30-C7-C11-
SEQ ID NO: 370
SEQ ID NO: 373


D4_hVH4-
QVQLQESGPGLVKPSQTLSLT
DIVMTQSPDSLAVSLGERATI


hVL2_PTM
CAVYGYSITSDYAWNWIRQP
NCKSSQSLLQSSTQKNYLA



PGKGLEWIGYISHSGSTSYNPS
WYQQKPGQPPKLLIYFASTR



LKSRVTISRDTSKNQFSLKLSS
DSGVPDRFSGSGSGTDFTLTI



VTAADTAVYYCARSLGRRW
SSLQAEDLAVYFCQQHYIIPF




YFDVWGQGTTVTVSS


TFGQGTKLEIK






30-C7-C11-
SEQ ID NO: 370
SEQ ID NO: 371


D4_hVH4-
QVQLQESGPGLVKPSQTLSLT
DIVMTQSPLSLPVTPGEPASI


hVL5_PTM
CAVYGYSITSDYAWNWIRQP
SCKSSQSLLQSSTQKNYLAW



PGKGLEWIGYISHSGSTSYNPS
YLQKPGQSPQLLIYFASTRDS



LKSRVTISRDTSKNQFSLKLSS
GVPDRFSGSGSGTDFTLKISR



VTAADTAVYYCARSLGRRW
VEAEDLGVYFCQQHYIIPFTF




YFDVWGQGTTVTVSS

GQGTKLEIK









In certain embodiments, the humanized antibodies or antigen-binding fragments thereof provided herein are composed of substantially all human sequences except for the CDR sequences which are non-human. In some embodiments, the variable region FRs, and constant regions if present, are entirely or substantially from human immunoglobulin sequences. The human FR sequences and human constant region sequences may be derived from different human immunoglobulin genes, for example, FR sequences derived from one human antibody and constant region from another human antibody. In some embodiments, the humanized antibody or antigen-binding fragment thereof comprises human heavy chain HFR1-4, and/or light chain LFR1-4.


In some embodiments, the FR regions derived from human may comprise the same amino acid sequence as the human immunoglobulin from which it is derived. In some embodiments, one or more amino acid residues of the human FR are substituted with the corresponding residues from the parent non-human antibody. This may be desirable in certain embodiments to make the humanized antibody or its fragment closely approximate the non-human parent antibody structure, so as to optimize binding characteristics (for example, increase binding affinity). In certain embodiments, the humanized antibody or antigen-binding fragment thereof provided herein comprises no more than 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 amino acid residue substitutions in each of the human FR sequences, or no more than 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 amino acid residue substitutions in all the FR sequences of a heavy or a light chain variable domain. In some embodiments, such change in amino acid residue could be present in heavy chain FR regions only, in light chain FR regions only, or in both chains. In certain embodiments, one or more amino acids of the human FR sequences are randomly mutated to increase binding affinity. In certain embodiments, one or more amino acids of the human FR sequences are back mutated to the corresponding amino acid(s) of the parent non-human antibody so as to increase binding affinity.


In certain embodiments, the anti-CD276 antibodies and the fragments thereof provided herein further comprise an immunoglobulin constant region. In some embodiments, an immunoglobulin constant region comprises a heavy chain and/or a light chain constant region. The heavy chain constant region comprises CH1, hinge, and/or CH2-CH3 regions. In certain embodiments, the heavy chain constant region comprises an Fc region. In certain embodiments, the light chain constant region comprises CK or CA.


In some embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof provided herein have a constant region of an immunoglobulin (Ig), optionally a human Ig, optionally a human IgG. In some embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof provided herein comprises a constant region of human IgG1, IgG2, IgG3, or IgG4.


Human IgG isotypes (the subclasses of mature gamma globulin class G antibodies; IgG1, IgG2, IgG3 and IgG4) exhibit differential capacity to recruit effector functions. For example, ADCC is promoted by IgG1 and IgG3, ADCP is promoted by IgG1, IgG2, IgG3 and IgG4, and CDC is promoted by IgG1 and IgG3. Isotype-specific engagement of such effector functions is based on selectivity for Fc receptors on distinct immune cells and the ability to bind C1q thereby activating the assembly of a membrane attack complex (MAC). Among the various isotypes, relative affinity for Fcγ receptors, which include FcγRI, FcγRIIa/b/c, and FcγRIIIa/b is high for IgG1 and IgG3. However, Fcγ affinity for IgG2 is considerably lower with the exception of FcγRIIa H131 polymorphism and IgG4 only has measurable affinity for FcγRI.


In certain embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof provided herein comprises a constant region of human IgG1 isotype, which could induce ADCC, CDC or ADCP, or a constant region of IgG4 or IgG2 isotype, which has reduced or depleted effector function. Effector functions such as ADCC and CDC can lead to cytotoxicity to cells expressing CD276. Effector functions can be evaluated using various assays such as Fc receptor binding assay, C1q binding assay, and cell lysis assay.


In certain embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof provided herein comprises a constant region of mouse IgG2 isotype, which could induce ADCC, CDC or ADCP.


Antibody Variants

The present disclosure also encompasses various variants of the antibodies and/or antigen-binding fragments thereof provided herein. In certain embodiments, the present disclosure encompasses various types of variants of an exemplary antibody provided herein, i.e., the antibody with a heavy chain CDR3 sequence selected from the group consisting of SEQ ID NOs: 3, 11, 19, 27, 35, 43, 51, 59, 67, 75, 83, 91, 99, 107, 115, 123, 131, 139, 147, 155, 163, 171, 179, 187, 195, 203, 211, 219, 227, 235, 243, 251, 259, 267, 275, 283, 291, 299, 307, 315, 323, 331, 339, or 375.


In certain embodiments, the antibody variants comprise one or more modifications or substitutions in one or more CDR sequences as provided in Table 1, one or more FR sequences, the heavy or light chain variable region sequences provided in Table 2, and/or the constant region (e.g. Fc region). Such variants retain specific binding affinity to CD276 of their parent antibodies, but have one or more desirable properties conferred by the modification(s) or substitution(s). For example, the antibody variants may have improved antigen-binding affinity, improved glycosylation pattern, reduced risk of glycosylation, reduced deamination, reduced or depleted effector function(s), improved FcRn receptor binding, increased pharmacokinetic half-life, pH sensitivity, and/or compatibility to conjugation (e.g. one or more introduced cysteine residues).


The parent antibody sequence may be screened to identify suitable or preferred residues to be modified or substituted, using methods known in the art, for example “alanine scanning mutagenesis” (see, for example, Cunningham and Wells (1989) Science, 244:1081-1085). Briefly, target residues (e.g., charged residues such as Arg, Asp, His, Lys, and Glu) can be identified and replaced by a neutral or negatively charged amino acid (e.g., alanine or polyalanine), and the modified antibodies are produced and screened for the interested property. If substitution at a particular amino acid location demonstrates an interested functional change, then the position can be identified as a potential residue for modification or substitution. The potential residues may be further assessed by substituting with a different type of residue (e.g. cysteine residue, positively charged residue, etc.).


Affinity Variant

Affinity variant may contain modifications or substitutions in one or more CDR sequences as provided in Table 1, one or more FR sequences, or the heavy or light chain variable region sequences in provided in Table 2, 3 or 4. The affinity variants retain specific binding affinity to CD276 of the parent antibody, or even have improved CD276 specific binding affinity over the parent antibody. In certain embodiments, at least one (or all) of the substitution(s) in the CDR sequences, FR sequences, or variable region sequences comprises a conservative substitution.


A skilled artisan will understand that in the CDR sequences provided in Table 1 and FR sequences, one or more amino acid residues may be substituted yet the resulting antibody or antigen-binding fragment still retain the binding affinity to CD276, or even have an improved binding affinity. Various methods known in the art can be used to achieve this purpose. For example, a library of antibody variants (such as Fab or scFv variants) can be generated and expressed with phage display technology, and then screened for the binding affinity to human CD276. For another example, computer software can be used to virtually simulate the binding of the antibodies to human CD276, and identify the amino acid residues on the antibodies which form the binding interface. Such residues may be either avoided in the substitution so as to prevent reduction in binding affinity, or targeted for substitution to provide for a stronger binding.


In certain embodiments, the humanized antibody or antigen-binding fragment provided herein comprises one or more amino acid residue substitutions in one or more CDR sequences, and/or one or more FR sequences. In certain embodiments, an affinity variant comprises no more than 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 substitutions in the CDR sequences and/or FR sequences in total.


In certain embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof comprise 1, 2, or 3 CDR sequences having at least 80% (e.g. at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%) sequence identity to that (or those) listed in Table 1, and in the meantime retain the binding affinity to CD276 at a level similar to or even higher than its parent antibody.


In certain embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof comprise one or more variable region sequences having at least 80% (e.g. at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%) sequence identity to that (or those) listed in Table 1, and in the meantime retain the binding affinity to CD276 at a level similar to or even higher than its parent antibody. In some embodiments, a total of 1 to 10 amino acids have been substituted, inserted, or deleted in a sequence selected from that (or those) listed in Table 1. In some embodiments, the substitutions, insertions, or deletions occur in regions outside the CDRs (i.e., in the FRs).


Glycosylation Variant

The anti-CD276 antibodies and antigen-binding fragments provided herein also encompass a glycosylation variant, which can be obtained to either increase or decrease the extent of glycosylation of the antibody or antigen binding fragment thereof.


The antibody or antigen binding fragment thereof may comprise one or more amino acid residues with a side chain to which a carbohydrate moiety (e.g. an oligosaccharide structure) can be attached. Glycosylation of antibodies is typically either N-linked or O-linked. N-linked refers to the attachment of the carbohydrate moiety to the side chain of an asparagine residue, for example, an asparagine residue in a tripeptide sequence such as asparagine-X-serine and asparagine-X-threonine, where X is any amino acid except proline. O-linked glycosylation refers to the attachment of one of the sugars N-aceylgalactosamine, galactose, or xylose to a hydroxyamino acid, most commonly to serine or threonine. Removal of a native glycosylation site can be conveniently accomplished, for example, by altering the amino acid sequence such that one of the above-described tripeptide sequences (for N-linked glycosylation sites) or serine or threonine residues (for O-linked glycosylation sites) present in the sequence is substituted. A new glycosylation site can be created in a similar way by introducing such a tripeptide sequence or serine or threonine residue.


Cysteine-Engineered Variant

The anti-CD276 antibodies and antigen-binding fragments provided herein also encompass a cysteine-engineered variant, which comprises one or more introduced free cysteine amino acid residues.


A free cysteine residue is one which is not part of a disulfide bridge. A cysteine-engineered variant is useful for conjugation with for example, a cytotoxic and/or imaging compound, a label, or a radioisoptype among others, at the site of the engineered cysteine, through for example a maleimide or haloacetyl. Methods for engineering antibodies or antigen-binding fragments to introduce free cysteine residues are known in the art, see, for example, WO2006/034488.


Fc Variant

The anti-CD276 antibodies and antigen-binding fragments provided herein also encompass an Fc variant, which comprises one or more amino acid residue modifications or substitutions at its Fc region and/or hinge region.


In certain embodiments, the anti-CD276 antibodies or antigen-binding fragments comprise one or more amino acid substitution(s) that improves pH-dependent binding to neonatal Fc receptor (FcRn). Such a variant can have an extended pharmacokinetic half-life, as it binds to FcRn at acidic pH which allows it to escape from degradation in the lysosome and then be translocated and released out of the cell. Methods of engineering an antibody and antigen-binding fragment thereof to improve binding affinity with FcRn are well-known in the art, see, for example, Vaughn, D. et al, Structure, 6 (1): 63-73, 1998; Kontermann, R. et al, Antibody Engineering, Volume 1, Chapter 27: Engineering of the Fc region for improved P K, published by Springer, 2010; Yeung, Y. et al, Cancer Research, 70:3269-3277 (2010); and Hinton, P. et al, J. Immunology, 176:346-356 (2006).


In certain embodiments, the anti-CD276 antibodies or antigen-binding fragments comprise one or more amino acid substitution(s) that alters the antibody-dependent cellular cytotoxicity (ADCC). Certain amino acid residues at CH2 domain of the Fc region can be substituted to provide for enhanced ADCC activity. Alternatively or additionally, carbohydrate structures on the antibody can be changed to enhance ADCC activity. Methods of altering ADCC activity by antibody engineering have been described in the art, see for example, Shields R L. et al., J Biol Chem. 2001. 276 (9): 6591-604; Idusogie E E. et al., J Immunol. 2000.164 (8): 4178-84; Steurer W. et al., J Immunol. 1995, 155 (3): 1165-74; Idusogie E E. et al., J Immunol. 2001, 166 (4): 2571-5; Lazar G A. et al., PNAS, 2006, 103 (11): 4005-4010; Ryan M C. et al., Mol. Cancer Ther., 2007, 6:3009-3018; Richards J O., et al., Mol Cancer Ther. 2008, 7 (8): 2517-27; Shields R. L. et al, J. Biol. Chem, 2002, 277:26733-26740; Shinkawa T. et al, J. Biol. Chem, 2003, 278:3466-3473.


In certain embodiments, the anti-CD276 antibodies or antigen-binding fragments comprise one or more amino acid substitution(s) that alters Complement Dependent Cytotoxicity (CDC), for example, by improving or diminishing C1q binding and/or CDC (see, for example, WO99/51642; Duncan & Winter Nature 322:738-40 (1988); U.S. Pat. Nos. 5,648,260; 5,624,821); and WO94/29351 concerning other examples of Fc region variants.


In certain embodiments, the anti-CD276 antibodies or antigen-binding fragments thereof comprise one or more amino acid substitution(s) in the interface of the Fc region to facilitate and/or promote heterodimerization. These modifications comprise introduction of a protuberance into a first Fc polypeptide and a cavity into a second Fc polypeptide, wherein the protuberance can be positioned in the cavity so as to promote interaction of the first and second Fc polypeptides to form a heterodimer or a complex. Methods of generating antibodies with these modifications are known in the art, e.g., as described in U.S. Pat. No. 5,731,168.


Antigen-Binding Fragments

Provided herein are also anti-CD276 antigen-binding fragments. Various types of antigen-binding fragments are known in the art and can be developed based on the anti-CD276 antibodies provided herein, including for example, the exemplary antibodies whose CDR and FR sequences are shown in Table 1, and their different variants (such as affinity variants, glycosylation variants, Fc variants, cysteine-engineered variants and so on).


In certain embodiments, an anti-CD276 antigen-binding fragment provided herein is a camelized single domain antibody, a single chain Fv fragment (scFv), a dsFv, a (dsFv)2, an Fv fragment, a Fab, a Fab′, a F(ab′)2, a nanobody, a domain antibody, a single domain antibody, or a bivalent domain antibody.


Various techniques can be used for the production of such antigen-binding fragments. Illustrative methods include, enzymatic digestion of intact antibodies (see, e.g., Morimoto et al., Journal of Biochemical and Biophysical Methods 24:107-117 (1992); and Brennan et al., Science, 229:81 (1985)), recombinant expression by host cells such as E. Coli (e.g. for Fab, Fv and ScFv antibody fragments), screening from a phage display library as discussed above (e.g. for ScFv), and chemical coupling of two Fab′-SH fragments to form F(ab′)2 fragments (Carter et al., Bio/Technology 10:163-167 (1992)). Other techniques for the production of antibody fragments will be apparent to a skilled practitioner.


In certain embodiments, the antigen-binding fragment is a scFv. Generation of scFv is described in, for example, WO 93/16185; U.S. Pat. Nos. 5,571,894; and 5,587,458. scFv may be fused to an effector protein at either the amino or the carboxy terminus to provide for a fusion protein (see, for example, Antibody Engineering, ed. Borrebaeck).


Conjugates

In some embodiments, the anti-CD276 antibodies and antigen-binding fragments thereof is linked to one or more conjugates, optionally, wherein the conjugate is covalently attached either directly or via a linker. A conjugate is a non-proteinaceous moiety that can be attached to the antibody or antigen-binding fragment thereof. It is contemplated that a variety of conjugates may be linked to the antibodies or antigen-binding fragments provided herein (see, for example, “Conjugate Vaccines”, Contributions to Microbiology and Immunology, J. M. Cruse and R. E. Lewis, Jr. (eds.), Carger Press, New York, (1989)). These conjugates may be linked to the antibodies or antigen-binding fragments by covalent binding, affinity binding, intercalation, coordinate binding, complexation, association, blending, or addition, among other methods. In some embodiments, the conjugate comprises a clearance-modifying agent, a chemotherapeutic agent, a toxin, a radioactive isotope, a lanthanide, a luminescent label, a fluorescent label, an enzyme-substrate label, a DNA-alkylators, a topoisomerase inhibitor, a tubulin-binders, or other anticancer drugs.


In certain embodiments, the antibodies and antigen-binding fragments disclosed herein may be engineered to contain specific sites outside the epitope binding portion that may be utilized for binding to one or more conjugates. For example, such a site may include one or more reactive amino acid residues, such as for example cysteine or histidine residues, to facilitate covalent linkage to a conjugate.


In certain embodiments, the antibodies may be linked to a conjugate indirectly, or through another conjugate. For example, the antibody or antigen-binding fragments may be conjugated to biotin, then indirectly conjugated to a second conjugate that is conjugated to avidin. The conjugate can be a toxin (e.g., a chemotherapeutic agent), a detectable label (e.g., a radioactive isotope, a lanthanide, a luminescent label, a fluorescent label, or an enzyme-substrate label).


A “toxin” can be any agent that is detrimental to cells or that can damage or kill cells. Examples of toxin include, without limitation, taxol, cytochalasin B, gramicidin D, ethidium bromide, emetine, mitomycin, etoposide, tenoposide, vincristine, vinblastine, colchicin, doxorubicin, daunorubicin, dihydroxy anthracin dione, mitoxantrone, mithramycin, actinomycin D, 1-dehydrotestosterone, glucocorticoids, procaine, tetracaine, lidocaine, propranolol, puromycin and analogs thereof, antimetabolites (e.g., methotrexate, 6-mercaptopurine, 6-thioguanine, cytarabine, 5-fluorouracil decarbazine), alkylating agents (e.g., mechlorethamine, thioepa chlorambucil, melphalan, carmustine (BSNU) and lomustine (CCNU), cyclothosphamide, busulfan, dibromomannitol, streptozotocin, mitomycin C, and cis-dichlorodiamine platinum (II) (DDP) cisplatin), anthracyclines (e.g., daunorubicin (formerly daunomycin) and doxorubicin), antibiotics (e.g., dactinomycin (formerly actinomycin), bleomycin, mithramycin, and anthramycin (AMC)), and anti-mitotic agents (e.g., vincristine and vinblastine).


Examples of detectable label may include a fluorescent labels (e.g. fluorescein, rhodamine, dansyl, phycoerythrin, or Texas Red), enzyme-substrate labels (e.g. horseradish peroxidase, alkaline phosphatase, luceriferases, glucoamylase, lysozyme, saccharide oxidases or β-D-galactosidase), radioisotopes (e.g. 123I, 124I, 125I, 131I, 35S, 3H, 111In, 112In, 14C, 64Cu, 67Cu, 86Y, 88Y, 90Y, 177Lu, 211At, 186Re, 188Re, 153Sm, 212Bi, and 32P, other lanthanides, luminescent labels), chromophoric moiety, digoxigenin, biotin/avidin, a DNA molecule or gold for detection.


In certain embodiments, the conjugate can be a pharmacokinetic modifying moiety which helps increase half-life of the antibody. Illustrative example include water-soluble polymers, such as PEG, carboxymethylcellulose, dextran, polyvinyl alcohol, polyvinyl pyrrolidone, copolymers of ethylene glycol/propylene glycol, and the like. The polymer may be of any molecular weight, and may be branched or unbranched. The number of polymers attached to the antibody may vary, and if more than one polymer are attached, they can be the same or different molecules.


In certain embodiments, the conjugate can be a purification moiety such as a magnetic bead.


In certain embodiments, the antibodies and/or antigen-binding fragments thereof provided herein is used for a base for a conjugate.


Polynucleotides and Recombinant Methods

The present disclosure provides isolated polynucleotides that encode the anti-CD276 antibodies and antigen-binding fragments thereof. DNA encoding the monoclonal antibody is readily isolated and sequenced using conventional procedures (e.g., by using oligonucleotide probes that are capable of binding specifically to genes encoding the heavy and light chains of the antibody). The encoding DNA may also be obtained by synthetic methods.


The isolated polynucleotide that encodes the anti-CD276 antibodies and antigen-binding fragments thereof can be inserted into a vector for further cloning (amplification of the DNA) or for expression, using recombinant techniques known in the art. Many vectors are available. The vector components generally include, but are not limited to, one or more of the following: a signal sequence, an origin of replication, one or more marker genes, an enhancer element, a promoter (e.g. SV40, CMV, EF-1α), and a transcription termination sequence.


In some embodiments, the vector system includes mammalian, bacterial, yeast systems, etc, and comprises plasmids such as, but not limited to, pALTER, pBAD, pcDNA, pCal, pL, pET, pGEMEX, pGEX, pCI, pCMV, PEGFP, pEGFT, pSV2, pFUSE, pVITRO, pVIVO, pMAL, pMD18-T, pMONO, pSELECT, pUNO, pDUO, Psg5L, pBABE, pWPXL, pBI, p15TV-L, pPro18, pTD, pRS420, pLexA, pACT2.2 etc, and other laboratorial and commercially available vectors. Suitable vectors may include, plasmid, or viral vectors (e.g., replication defective retroviruses, adenoviruses and adeno-associated viruses).


Vectors comprising the polynucleotide sequence encoding the antibody or antigen-binding fragment can be introduced to a host cell for cloning or gene expression. Suitable host cells for cloning or expressing the DNA in the vectors herein are the prokaryote, yeast, or higher eukaryote cells described above. Suitable prokaryotes for this purpose include eubacteria, such as Gram-negative or Gram-positive organisms, for example, Enterobacteriaceae such as Escherichia, e.g., E. coli, Enterobacter, Erwinia, Klebsiella, Proteus, Salmonella, e.g., Salmonella typhimurium, Serratia, e.g., Serratia marcescans, and Shigella, as well as Bacilli such as B. subtilis and B. licheniformis, Pseudomonas such as P. aeruginosa, and Streptomyces.


In addition to prokaryotes, eukaryotic microbes such as filamentous fungi or yeast are suitable cloning or expression hosts for anti-CD276 antibody-encoding vectors. Saccharomyces cerevisiae, or common baker's yeast, is the most commonly used among lower eukaryotic host microorganisms. However, a number of other genera, species, and strains are commonly available and useful herein, such as Schizosaccharomyces pombe; Kluyveromyces hosts such as, e.g., K. lactis, K. fragilis (ATCC 12,424), K. bulgaricus (ATCC 16,045), K. wickeramii (ATCC 24,178), K. waltii (ATCC 56,500), K. drosophilarum (ATCC 36,906), K. thermotolerans, and K. marxianus; yarrowia (EP 402,226); Pichia pastoris (EP 183,070); Candida; Trichoderma reesia (EP 244,234); Neurospora crassa; Schwanniomyces such as Schwanniomyces occidentalis; and filamentous fungi such as, e.g., Neurospora, Penicillium, Tolypocladium, and Aspergillus hosts such as A. nidulans and A. niger.


Suitable host cells for the expression of glycosylated antibodies or antigen-fragment provided here are derived from multicellular organisms. Examples of invertebrate cells include plant and insect cells. Numerous baculoviral strains and variants and corresponding permissive insect host cells from hosts such as Spodoptera frugiperda (caterpillar), Aedes aegypti (mosquito), Aedes albopictus (mosquito), Drosophila melanogaster (fruiffly), and Bombyx mori have been identified. A variety of viral strains for transfection are publicly available, e.g., the L-1 variant of Autographa californica NPV and the Bm-5 strain of Bombyx mori NPV, and such viruses may be used as the virus herein according to the present invention, particularly for transfection of Spodoptera frugiperda cells. Plant cell cultures of cotton, corn, potato, soybean, petunia, tomato, and tobacco can also be utilized as hosts.


However, interest has been greatest in vertebrate cells, and propagation of vertebrate cells in culture (tissue culture) has become a routine procedure. Examples of useful mammalian host cell lines are monkey kidney CV1 line transformed by SV40 (COS-7, ATCC CRL 1651); human embryonic kidney line (293 or 293 cells subcloned for growth in suspension culture, Graham et al., J. Gen Virol. 36:59 (1977)); baby hamster kidney cells (BHK, ATCC CCL 10); Chinese hamster ovary cells/-DHFR (CHO, Urlaub et al., Proc. Natl. Acad. Sci. USA 77:4216 (1980)); mouse sertoli cells (TM4, Mather, Biol. Reprod. 23:243-251 (1980)); monkey kidney cells (CV1 ATCC CCL 70); African green monkey kidney cells (VERO-76, ATCC CRL-1587); human cervical carcinoma cells (HELA, ATCC CCL 2); canine kidney cells (MDCK, ATCC CCL 34); buffalo rat liver cells (BRL 3A, ATCC CRL 1442); human lung cells (W138, ATCC CCL 75); human liver cells (Hep G2, HB 8065); mouse mammary tumor (MMT 060562, ATCC CCL51); TRI cells (Mather et al., Annals N.Y. Acad. Sci. 383:44-68 (1982)); MRC 5 cells; FS4 cells; and a human hepatoma line (Hep G2).


Host cells are transformed with the above-described expression or cloning vectors for anti-CD276 antibody production and cultured in conventional nutrient media modified as appropriate for inducing promoters, selecting transformants, or amplifying the genes encoding the desired sequences. In another embodiment, the antibody may be produced by homologous recombination known in the art.


The host cells used to produce the antibodies or antigen-binding fragments provided herein may be cultured in a variety of media. Commercially available media such as Ham's F10 (Sigma), Minimal Essential Medium (MEM), (Sigma), RPMI-1640 (Sigma), and Dulbecco's Modified Eagle's Medium (DMEM), Sigma) are suitable for culturing the host cells. In addition, any of the media described in Ham et al., Meth. Enz. 58:44 (1979), Barnes et al., Anal. Biochem. 102:255 (1980), U.S. Pat. Nos. 4,767,704; 4,657,866; 4,927,762; 4,560,655; or 5,122,469; WO 90/03430; WO 87/00195; or U.S. Pat. Re. 30,985 may be used as culture media for the host cells. Any of these media may be supplemented as necessary with hormones and/or other growth factors (such as insulin, transferrin, or epidermal growth factor), salts (such as sodium chloride, calcium, magnesium, and phosphate), buffers (such as HEPES), nucleotides (such as adenosine and thymidine), antibiotics (such as GENTAMYCIN™ drug), trace elements (defined as inorganic compounds usually present at final concentrations in the micromolar range), and glucose or an equivalent energy source. Any other necessary supplements may also be included at appropriate concentrations that would be known to those skilled in the art. The culture conditions, such as temperature, pH, and the like, are those previously used with the host cell selected for expression, and will be apparent to the ordinarily skilled artisan.


When using recombinant techniques, the antibody can be produced intracellularly, in the periplasmic space, or directly secreted into the medium. If the antibody is produced intracellularly, as a first step, the particulate debris, either host cells or lysed fragments, is removed, for example, by centrifugation or ultrafiltration. Carter et al., Bio/Technology 10:163-167 (1992) describe a procedure for isolating antibodies which are secreted to the periplasmic space of E. coli. Briefly, cell paste is thawed in the presence of sodium acetate (pH 3.5), EDTA, and phenylmethylsulfonylfluoride (PMSF) over about 30 min. Cell debris can be removed by centrifugation. Where the antibody is secreted into the medium, supernatants from such expression systems are generally first concentrated using a commercially available protein concentration filter, for example, an Amicon or Millipore Pellicon ultrafiltration unit. A protease inhibitor such as PMSF may be included in any of the foregoing steps to inhibit proteolysis and antibiotics may be included to prevent the growth of adventitious contaminants.


The anti-CD276 antibodies and antigen-binding fragments thereof prepared from the cells can be purified using, for example, hydroxylapatite chromatography, gel electrophoresis, dialysis, DEAE-cellulose ion exchange chromatography, ammonium sulfate precipitation, salting out, and affinity chromatography, with affinity chromatography being the preferred purification technique.


In certain embodiments, Protein A immobilized on a solid phase is used for immunoaffinity purification of the antibody and antigen-binding fragment thereof. The suitability of protein A as an affinity ligand depends on the species and isotype of any immunoglobulin Fc domain that is present in the antibody. Protein A can be used to purify antibodies that are based on human gamma1, gamma2, or gamma4 heavy chains (Lindmark et al., J. Immunol. Meth. 62:1-13 (1983)). Protein G is recommended for all mouse isotypes and for human gamma3 (Guss et al., EMBO J. 5:1567 1575 (1986)). The matrix to which the affinity ligand is attached is most often agarose, but other matrices are available. Mechanically stable matrices such as controlled pore glass or poly(styrenedivinyl)benzene allow for faster flow rates and shorter processing times than can be achieved with agarose. Where the antibody comprises a CH3 domain, the Bakerbond ABX™ resin (J. T. Baker, Phillipsburg, N.J.) is useful for purification. Other techniques for protein purification such as fractionation on an ion-exchange column, ethanol precipitation, Reverse Phase HPLC, chromatography on silica, chromatography on heparin SEPHAROSE™ chromatography on an anion or cation exchange resin (such as a polyaspartic acid column), chromatofocusing, SDS-PAGE, and ammonium sulfate precipitation are also available depending on the antibody to be recovered.


Following any preliminary purification step(s), the mixture comprising the antibody of interest and contaminants may be subjected to low pH hydrophobic interaction chromatography using an elution buffer at a pH between about 2.5-4.5, preferably performed at low salt concentrations (e.g., from about 0-0.25M salt).


CAR

In another aspect, the present disclosure also provides chimeric antigen receptor (CAR) comprising an antigen binding domain, a transmembrane domain, a costimulatory signaling region, and a TCR signaling domain, wherein the antigen binding domain specifically binds to CD276 and comprises an antigen binding fragment provided herein. In certain embodiments, the antigen binding fragment is a Fab or a scFv. In certain embodiments, the CAR provided herein is bispecific. The CAR is capable of further specifically binding to a second antigen other than CD276, or a second epitope on CD276. In certain embodiments, the second antigen is a tumor antigen, tumor associated antigen, or an immune related target as mentioned above. The TCR signaling domain can be selected from the group consisting of: an intracellular signal regions sequence of CD3ζ, FccRIγ, CD27, CD28, CD137, CD134, MyD88, CD40, CD278, TLRs, or a combination thereof. The transmembrane region can comprise a transmembrane region of CD3, CD4, CD8 or CD28. In certain embodiments, the second antigen is an immunoinhibitory molecule, such as PD-L1, SIRPα, CD47 or B2M.


In another aspect, the present disclosure also provides a nucleic acid sequence encoding the CAR as mentioned above as well as a cell or a vector comprising such nucleic acid sequence or a cell genetically modified to express the CAR provided herein. The cell can be an immune cell, optionally, wherein the immune cell is T lymphocyte, NK cell, monocyte, macrophage or NKT lymphocyte.


Pharmaceutical Composition

The present disclosure further provides pharmaceutical compositions comprising the anti-CD276 antibodies or antigen-binding fragments thereof and one or more pharmaceutically acceptable carriers.


Pharmaceutical acceptable carriers for use in the pharmaceutical compositions disclosed herein may include, for example, pharmaceutically acceptable liquid, gel, or solid carriers, aqueous vehicles, nonaqueous vehicles, antimicrobial agents, isotonic agents, buffers, antioxidants, anesthetics, suspending/dispending agents, sequestering or chelating agents, diluents, adjuvants, excipients, or non-toxic auxiliary substances, other components known in the art, or various combinations thereof.


Suitable components may include, for example, antioxidants, fillers, binders, disintegrants, buffers, preservatives, lubricants, flavorings, thickeners, coloring agents, emulsifiers or stabilizers such as sugars and cyclodextrins. Suitable antioxidants may include, for example, methionine, ascorbic acid, EDTA, sodium thiosulfate, platinum, catalase, citric acid, cysteine, thioglycerol, thioglycolic acid, thiosorbitol, butylated hydroxanisol, butylated hydroxytoluene, and/or propyl gallate. As disclosed herein, inclusion of one or more antioxidants such as methionine in a composition comprising an antibody or antigen-binding fragment and conjugates as provided herein decreases oxidation of the antibody or antigen-binding fragment. This reduction in oxidation prevents or reduces loss of binding affinity, thereby improving antibody stability and maximizing shelf-life. Therefore, in certain embodiments compositions are provided that comprise one or more antibodies or antigen-binding fragments thereof as disclosed herein and one or more antioxidants such as methionine. Further provided are methods for preventing oxidation of, extending the shelf-life of, and/or improving the efficacy of an antibody or antigen-binding fragment as provided herein by mixing the antibody or antigen-binding fragment with one or more antioxidants such as methionine.


To further illustrate, pharmaceutical acceptable carriers may include, for example, aqueous vehicles such as sodium chloride injection, Ringer's injection, isotonic dextrose injection, sterile water injection, or dextrose and lactated Ringer's injection, nonaqueous vehicles such as fixed oils of vegetable origin, cottonseed oil, corn oil, sesame oil, or peanut oil, antimicrobial agents at bacteriostatic or fungistatic concentrations, isotonic agents such as sodium chloride or dextrose, buffers such as phosphate or citrate buffers, antioxidants such as sodium bisulfate, local anesthetics such as procaine hydrochloride, suspending and dispersing agents such as sodium carboxymethylcelluose, hydroxypropyl methylcellulose, or polyvinylpyrrolidone, emulsifying agents such as Polysorbate 80 (TWEEN-80), sequestering or chelating agents such as EDTA (ethylenediaminetetraacetic acid) or EGTA (ethylene glycol tetraacetic acid), ethyl alcohol, polyethylene glycol, propylene glycol, sodium hydroxide, hydrochloric acid, citric acid, or lactic acid. Antimicrobial agents utilized as carriers may be added to pharmaceutical compositions in multiple-dose containers that include phenols or cresols, mercurials, benzyl alcohol, chlorobutanol, methyl and propyl p-hydroxybenzoic acid esters, thimerosal, benzalkonium chloride and benzethonium chloride. Suitable excipients may include, for example, water, saline, dextrose, glycerol, or ethanol. Suitable non-toxic auxiliary substances may include, for example, wetting or emulsifying agents, pH buffering agents, stabilizers, solubility enhancers, or agents such as sodium acetate, sorbitan monolaurate, triethanolamine oleate, or cyclodextrin.


The pharmaceutical compositions can be a liquid solution, suspension, emulsion, pill, capsule, tablet, sustained release formulation, or powder. Oral formulations can include standard carriers such as pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, polyvinyl pyrollidone, sodium saccharine, cellulose, magnesium carbonate, etc.


In certain embodiments, the pharmaceutical compositions are formulated into an injectable composition. The injectable pharmaceutical compositions may be prepared in any conventional form, such as for example liquid solution, suspension, emulsion, or solid forms suitable for generating liquid solution, suspension, or emulsion. Preparations for injection may include sterile and/or non-pyretic solutions ready for injection, sterile dry soluble products, such as lyophilized powders, ready to be combined with a solvent just prior to use, including hypodermic tablets, sterile suspensions ready for injection, sterile dry insoluble products ready to be combined with a vehicle just prior to use, and sterile and/or non-pyretic emulsions. The solutions may be either aqueous or nonaqueous.


In certain embodiments, unit-dose parenteral preparations are packaged in an ampoule, a vial or a syringe with a needle. All preparations for parenteral administration should be sterile and not pyretic, as is known and practiced in the art.


In certain embodiments, a sterile, lyophilized powder is prepared by dissolving an antibody or antigen-binding fragment as disclosed herein in a suitable solvent. The solvent may contain an excipient which improves the stability or other pharmacological components of the powder or reconstituted solution, prepared from the powder. Excipients that may be used include, but are not limited to, water, dextrose, sorbital, fructose, corn syrup, xylitol, glycerin, glucose, sucrose or other suitable agents. The solvent may contain a buffer, such as citrate, sodium or potassium phosphate or other such buffer known to those of skill in the art at, in one embodiment, about neutral pH. Subsequent sterile filtration of the solution followed by lyophilization under standard conditions known to those of skill in the art provides a desirable formulation. In one embodiment, the resulting solution will be apportioned into vials for lyophilization. Each vial can contain a single dosage or multiple dosages of the anti-CD276 antibody or antigen-binding fragment thereof or composition thereof. Overfilling vials with a small amount above that needed for a dose or set of doses (e.g., about 10%) is acceptable so as to facilitate accurate sample withdrawal and accurate dosing. The lyophilized powder can be stored under appropriate conditions, such as at about 4° C. to room temperature.


Reconstitution of a lyophilized powder with water for injection provides a formulation for use in parenteral administration. In one embodiment, for reconstitution the sterile and/or non-pyretic water or other liquid suitable carrier is added to lyophilized powder. The precise amount depends upon the selected therapy being given, and can be empirically determined.


Methods of Use

The present disclosure also provides therapeutic methods comprising: administering a therapeutically effective amount of the antibody or antigen-binding fragment thereof as provided herein to a subject in need thereof, thereby treating or preventing a CD276-related disease or condition. In some embodiment, the CD276-related disease or condition is cancer, autoimmune disease, inflammatory disease, adaptive immune disease or infectious disease.


Examples of cancer include but are not limited to, non-small cell lung cancer (squamous/nonsquamous), small cell lung cancer, renal cell cancer, colorectal cancer, colon cancer, ovarian cancer, breast cancer (including basal breast carcinoma, ductal carcinoma and lobular breast carcinoma), pancreatic cancer, gastric carcinoma, bladder cancer, esophageal cancer, mesothelioma, melanoma, head and neck cancer, thyroid cancer, sarcoma, prostate cancer, glioblastoma, cervical cancer, thymic carcinoma, melanoma, myelomas, mycoses fungoids, merkel cell cancer, hepatocellular carcinoma (HCC), fibrosarcoma, myxosarcoma, liposarcoma, chondrosarcoma, osteogenic sarcoma, and other sarcomas, synovioma, mesothelioma, Ewing's tumor, leiomyosarcoma, rhabdomyosarcoma, lymphoid malignancy, basal cell carcinoma, adenocarcinoma, sweat gland carcinoma, medullary thyroid carcinoma, papillary thyroid carcinoma, pheochromocytomas sebaceous gland carcinoma, papillary carcinoma, papillary adenocarcinomas, medullary carcinoma, bronchogenic carcinoma, hepatoma, bile duct carcinoma, choriocarcinoma, Wilms' tumor, cervical cancer, testicular tumor, seminoma, classical Hodgkin lymphoma (CHL), primary mediastinal large B-cell lymphoma, T-cell/histiocyte-rich B-cell lymphoma, acute lymphocytic leukemia, acute myelocytic leukemia, acute myelogenous leukemia, chronic myelocytic (granulocytic) leukemia, chronic myelogenous leukemia, chronic lymphocytic leukemia, polycythemia vera, mast cell derived tumors, EBV-positive and -negative PTLD, and diffuse large B-cell lymphoma (DLBCL), plasmablastic lymphoma, extranodal NK/T-cell lymphoma, nasopharyngeal carcinoma, HHV8-associated primary effusion lymphoma, non-Hodgkin's lymphoma, multiple myeloma, Waldenstrom's macroglobulinemia, heavy chain disease, myelodysplastic syndrome, hairy cell leukemia and myelodysplasia, primary CNS lymphoma, spinal axis tumor, brain stem glioma, astrocytoma, medulloblastoma, craniopharyogioma, ependymoma, pinealoma, hemangioblastoma, acoustic neuroma, oligodendroglioma, menangioma, melanoma, neuroblastoma and retinoblastoma.


In certain embodiments, the cancer is adrenal gland tumor, an AIDS-associated cancer, an alveolar soft part sarcoma, an astrocytic tumor, bladder cancer, bone cancer, a brain and spinal cord cancer, a metastatic brain tumor, a breast cancer, a carotid body tumors, a cervical cancer, a chondrosarcoma, a chordoma, a chromophobe renal cell carcinoma, a clear cell carcinoma, a colon cancer, a colorectal cancer, a cutaneous benign fibrous histiocytoma, a desmoplastic small round cell tumor, an ependymoma, a Ewing's tumor, an extraskeletal myxoid chondrosarcoma, a fibrogenesis imperfecta ossium, a fibrous dysplasia of the bone, a gallbladder or bile duct cancer, gastric cancer, a gestational trophoblastic disease, a germ cell tumor, a head and neck cancer, hepatocellular carcinoma, an islet cell tumor, a Kaposi's Sarcoma, a kidney cancer, a leukemia, a lipoma/benign lipomatous tumor, a liposarcoma/malignant lipomatous tumor, a liver cancer, a lymphoma, a lung cancer, a medulloblastoma, a melanoma, a meningioma, a multiple endocrine neoplasia, a multiple myeloma, a myelodysplastic syndrome, a neuroblastoma, a neuroendocrine tumors, an ovarian cancer, a pancreatic cancer, a papillary thyroid carcinoma, a parathyroid tumor, a pediatric cancer, a peripheral nerve sheath tumor, a phaeochromocytoma, a pituitary tumor, a prostate cancer, a posterior uveal melanoma, a rare hematologic disorder, a renal metastatic cancer, a rhabdoid tumor, a rhabdomysarcoma, a sarcoma, a skin cancer, a soft-tissue sarcoma, a squamous cell cancer, a stomach cancer, a synovial sarcoma, a testicular cancer, a thymic carcinoma, a thymoma, a thyroid metastatic cancer, and a uterine cancer. In certain embodiments, the cancer is chemoresistant.


In certain embodiments, the disease or condition is hematological cancer chosen from B-cell lymphomas. Examples of B-cell lymphomas includes but not limited to, Hodgkin's lymphoma, non-Hodgkin's lymphoma (NHL), acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), chronic myelogenous leukemia (CML), multiple myeloma (MM), diffuse large B cell lymphoma (DLBCL), Marginal zone B-cell lymphoma (MZL), Mantle cell lymphoma (MCL), Richter's syndrome, Burkitt's lymphoma or follicular lymphoma.


Autoimmune diseases include, but are not limited to, Acquired Immunodeficiency Syndrome (AIDS, which is a viral disease with an autoimmune component), alopecia areata, ankylosing spondylitis, antiphospholipid syndrome, autoimmune Addison's disease, autoimmune hemolytic anemia, autoimmune hepatitis, autoimmune inner ear disease (AIED), autoimmune lymphoproliferative syndrome (ALPS), autoimmune thrombocytopenia purpura (ATP), Behcet's disease, cardiomyopathy, celiac sprue-dermatitis hepetiformis; chronic fatigue immune dysfunction syndrome (CFIDS), chronic inflammatory demyelinating polyneuropathy (CIPD), cicatricial pemphigold, cold agglutinin disease, crest syndrome, Crohn's disease, Degos' disease, dermatomyositis-juvenile, discoid lupus, essential mixed cryoglobulinemia, fibromyalgia-fibromyositis, Graves' disease, Guillain-Barre syndrome, Hashimoto's thyroiditis, idiopathic pulmonary fibrosis, idiopathic thrombocytopenia purpura (ITP), IgA nephropathy, insulin-dependent diabetes mellitus, juvenile chronic arthritis (Still's disease), juvenile rheumatoid arthritis, Meniere's disease, mixed connective tissue disease, multiple sclerosis, myasthenia gravis, pemacious anemia, polyarteritis nodosa, polychondritis, polyglandular syndromes, polymyalgia rheumatica, polymyositis and dermatomyositis, primary agammaglobulinemia, primary biliary cirrhosis, psoriasis, psoriatic arthritis, Raynaud's phenomena, Reiter's syndrome, rheumatic fever, rheumatoid arthritis, sarcoidosis, scleroderma (progressive systemic sclerosis (PSS), also known as systemic sclerosis (SS)), Sjogren's syndrome, stiff-man syndrome, systemic lupus erythematosus, Takayasu arteritis, temporal arteritis/giant cell arteritis, ulcerative colitis, uveitis, vitiligo and Wegener's granulomatosis.


Inflammatory disorders, include, for example, chronic and acute inflammatory disorders. Examples of inflammatory disorders include Alzheimer's disease, asthma, atopic allergy, allergy, atherosclerosis, bronchial asthma, eczema, glomerulonephritis, graft vs. host disease, hemolytic anemias, osteoarthritis, sepsis, stroke, transplantation of tissue and organs, vasculitis, diabetic retinopathy and ventilator induced lung injury. In some embodiments, the CD276 associated conditions are inflammatory diseases such as systemic lupus erythematosus (SLE), intestinal mucosal inflammation, wasting disease associated with colitis, multiple sclerosis, viral infections, rheumatoid arthritis, osteoarthritis, Cohn's disease, and inflammatory bowel disease, psoriasis, systemic scleroderma, autoimmune diabetes and the like.


Infectious disease include, but are not limited to, fungus infection, parasite/protozoan infection or chronic viral infection, for example, malaria, coccidioiodmycosis immitis, histoplasmosis, onychomycosis, aspergilosis, blastomycosis, candidiasis albicans, paracoccidioiomycosis, microsporidiosis, Acanthamoeba keratitis, Amoebiasis, Ascariasis, Babesiosis, Balantidiasis, Baylisascariasis, Chagas disease, Clonorchiasis, Cochliomyia, Cryptosporidiosis, Diphyllobothriasis, Dracunculiasis, Echinococcosis, Elephantiasis, Enterobiasis, Fascioliasis, Fasciolopsiasis, Filariasis, Giardiasis, Gnathostomiasis, Hymenolepiasis, Isosporiasis, Katayama fever, Leishmaniasis, Lyme disease, Metagonimiasis, Myiasis, Onchocerciasis, Pediculosis, Scabies, Schistosomiasis, Sleeping sickness, Strongyloidiasis, Taeniasis, Toxocariasis, Toxoplasmosis, Trichinosis, Trichuriasis, Trypanosomiasis, helminth infection, infection of hepatitis B (HBV), hepatitis C (HCV), herpes virus, Epstein-Barr virus, HIV, cytomegalovirus, herpes simplex virus type I, herpes simplex virus type II, human papilloma virus, adenovirus, human immunodeficiency virus I, human immunodeficiency virus II, Kaposi West sarcoma associated herpes virus epidemics, thin ring virus (Torquetenovirus), human T lymphotrophic viruse I, human T lymphotrophic viruse II, varicella zoster, JC virus or BK virus.


In certain embodiments, the subject is human.


In another aspect, methods are provided to treat a disease or condition in a subject that would benefit from modulation of CD276 activity, comprising administering a therapeutically effective amount of the antibody or antigen-binding fragment thereof as provided herein to a subject in need thereof. The term “disease or condition” as used herein can be used interchangeably with the term “CD276-related disease or condition”.


The therapeutically effective amount of an antibody or antigen-binding fragment thereof as provided herein will depend on various factors known in the art, such as for example body weight, age, past medical history, present medications, state of health of the subject and potential for cross-reaction, allergies, sensitivities and adverse side-effects, as well as the administration route and extent of disease development. Dosages may be proportionally reduced or increased by one of ordinary skill in the art (e.g., physician or veterinarian) as indicated by these and other circumstances or requirements.


In certain embodiments, an antibody or antigen-binding fragment thereof as provided herein may be administered at a therapeutically effective dosage of about 0.01 mg/kg to about 100 mg/kg (e.g., about 0.01 mg/kg, about 0.5 mg/kg, about 1 mg/kg, about 2 mg/kg, about 3 mg/kg, about 5 mg/kg, about 10 mg/kg, about 15 mg/kg, about 20 mg/kg, about 25 mg/kg, about 30 mg/kg, about 35 mg/kg, about 40 mg/kg, about 45 mg/kg, about 50 mg/kg, about 55 mg/kg, about 60 mg/kg, about 65 mg/kg, about 70 mg/kg, about 75 mg/kg, about 80 mg/kg, about 85 mg/kg, about 90 mg/kg, about 95 mg/kg, or about 100 mg/kg). In certain of these embodiments, the antibody or antigen-binding fragment thereof is administered at a dosage of about 50 mg/kg or less, and in certain of these embodiments the dosage is 10 mg/kg or less, 5 mg/kg or less, 3 mg/kg or less, 1 mg/kg or less, 0.5 mg/kg or less, or 0.1 mg/kg or less. In certain embodiments, the administration dosage may change over the course of treatment. For example, in certain embodiments, the initial administration dosage may be higher than subsequent administration dosages. In certain embodiments, the administration dosage may vary over the course of treatment depending on the reaction of the subject.


Dosage regimens may be adjusted to provide the optimum desired response (e.g., a therapeutic response). For example, a single dose may be administered, or several divided doses may be administered over time.


The antibodies and antigen-binding fragments thereof disclosed herein may be administered by any route known in the art, such as for example parenteral (e.g., subcutaneous, intraperitoneal, intravenous, including intravenous infusion, intramuscular, or intradermal injection) or non-parenteral (e.g., oral, intranasal, intraocular, sublingual, rectal, or topical) routes.


In some embodiments, the antibodies or antigen-binding fragments thereof disclosed herein may be administered alone or in combination with one or more additional therapeutic means or agents. In some embodiments, the antibodies or antigen-binding fragments thereof disclosed herein may be administered alone or in combination with a second therapeutic agent. For example, the antibodies or antigen-binding fragments thereof disclosed herein may be administered in combination with a second therapeutic agent, for example, a chemotherapeutic agent or an anti-cancer drug. In certain embodiments, the antibodies or antigen-binding fragments thereof disclosed herein may be administered in combination with an antagonist of one or more immunoinhibitory molecule, e.g., CD24, CD47, SIRPα, PD-L1, or the beta-2 microglobulin subunit of the major histocompatibility class I complex (B2M). The term “antagonist” as used herein comprises can refer to any small molecule, small or micro RNAs, or antibodies or antigen-binding fragments thereof that blocks or inhibits binding of CD24, CD47, SIRPα, PD-L1 or B2M to their respective binding partners so as to prevent elicit of immunoinhibitory signals. In certain embodiments, the antibodies or antigen-binding fragments thereof disclosed herein is administered in combination with a PD-L1 antagonist, such as an anti-PD-L1 antibody or antigen-binding fragment thereof.


The term “anti-PD-L1 antibody” can refer to any known anti-PD-L1 antibodies or antigen-binding fragment thereof, including without limitation, YN035 as disclosed in WO2019196309A1, and MPDL3280A as disclosed in WO2010077634A1.


In certain of these embodiments, an antibody or antigen-binding fragment thereof as disclosed herein that is administered in combination with one or more additional therapeutic agents may be administered simultaneously with the one or more additional therapeutic agents, and in certain of these embodiments the antibody or antigen-binding fragment thereof and the additional therapeutic agent(s) may be administered as part of the same pharmaceutical composition. However, an antibody or antigen-binding fragment thereof administered “in combination” with another therapeutic agent does not have to be administered simultaneously with or in the same composition as the agent. An antibody or antigen-binding fragment thereof administered prior to or after another agent is considered to be administered “in combination” with that agent as the phrase is used herein, even if the antibody or antigen-binding fragment thereof and a second agent are administered via different routes. Where possible, additional therapeutic agents administered in combination with the antibodies or antigen-binding fragments thereof disclosed herein are administered according to the schedule listed in the product information sheet of the additional therapeutic agent, or according to the Physicians' Desk Reference 2003 (Physicians' Desk Reference, 57th Ed; Medical Economics Company; ISBN: 1563634457; 57th edition (November 2002)) or protocols well known in the art.


In some embodiments, the present disclosure provides methods of detecting presence or amount of CD276 in a sample, comprising contacting the sample with the antibody or antigen-binding fragment thereof, and determining the presence or the amount of CD276 in the sample.


In some embodiments, the present disclosure provides methods of diagnosing a CD276 related disease or condition in a subject, comprising: a) obtaining a sample from the subject; b) contacting the sample obtained from the subject with the antibody or antigen-binding fragment thereof provided herein; c) determining presence or amount of CD276 in the sample; and d) correlating the existence of the CD276 to the CD276 related disease or condition in the subject.


In some embodiments, the present disclosure also provides use of the antibody or antigen-binding fragment thereof provided herein in the manufacture of a medicament for treating a CD276 related disease or condition in a subject, in the manufacture of a diagnostic reagent for diagnosing a CD276 related disease or condition.


In another aspect, the present disclosure also provides a method of modulating CD276 activity in a CD276-expressing cell, comprising exposing the CD276-expressing cell to the antibody or antigen-binding fragment thereof provided herein.


In another aspect, the present disclosure also provides a method of detecting presence or amount of CD276 in a sample, comprising contacting the sample with the antibody or antigen-binding fragment thereof provided herein, and determining the presence or the amount of CD276 in the sample.


In another aspect, the present disclosure also provides a method of diagnosing a CD276 related disease or condition in a subject, comprising: a) obtaining a sample from the subject; b) contacting the sample obtained from the subject with the antibody or antigen-binding fragment thereof provided herein; c) determining presence or amount of CD276 in the sample; and d) correlating the presence or the amount of CD276 to existence or status of the CD276 related disease or condition in the subject.


In another aspect, the present disclosure also provides use of the antibody or antigen-binding fragment thereof provided herein in the manufacture of a medicament for treating a CD276 related disease or condition in a subject. The medicament can further comprise a second therapeutic agent, e.g., a PD-L1 antagonist, optionally, wherein the PD-L1 antagonist is an anti-PD-L1 antibody or antigen-binding fragment thereof.


In another aspect, the present disclosure also provides use of the antibody or antigen-binding fragment thereof provided herein in the manufacture of a diagnostic reagent for diagnosing a CD276 related disease or condition.


In another aspect, the present disclosure also provides a kit comprising the antibody or antigen-binding fragment thereof provided herein, useful in detecting CD276, optionally recombinant CD276, CD276 expressed on cell surface, or CD276-expressing cells. The term “recombinant” as used herein refers to artificial manipulation of one or more biological molecules such as polynucleotide or polypeptide molecules using one or more molecular biology techniques to make such biological molecule(s) into something other than its natural state.


In another aspect, the present disclosure also provides a method for stimulating a T cell-mediated immune response to a CD276-expressing cell or tissue in a mammal, the method comprising administering to the mammal an effective amount of a cell genetically modified to express the CAR comprising an antigen binding domain, a transmembrane domain, a costimulatory signaling region, and a TCR signaling domain, wherein the antigen binding domain specifically binds to CD276 and comprises an antigen binding fragment provided herein. In certain embodiments, the antigen binding fragment is a Fab or a scFv. In certain embodiments, the CAR provided herein is bispecific. The CAR is capable of further specifically binding to a second antigen other than CD276 or a second epitope on CD276. In certain embodiments, the second antigen is a tumor antigen as mentioned above. The TCR signaling domain can be selected from the group consisting of: an intracellular signal region sequence of CD3ζ, FccRIγ, CD27, CD28, CD137, CD134, MyD88, CD40, CD278, TLRs, or a combination thereof. The transmembrane region can comprise a transmembrane region of CD3, CD4, CD8 or CD28. In certain embodiments, the second antigen is an immunoinhibitory molecule, e.g., PD-L1, SIRPα, CD24, CD47 or B2M.


In another aspect, the present disclosure also provides method for treating a mammal having a CD276 related disease or condition, comprising administering to the mammal an effective amount of a cell that is genetically modified to express the CAR provided herein (e.g., an autologous T cell), thereby treating the mammal. In certain embodiments, the CD276 related disease or condition is cancer. In certain embodiments, the mammal is a human subject.


The following examples are provided to better illustrate the claimed invention and are not to be interpreted as limiting the scope of the invention. All specific compositions, materials, and methods described below, in whole or in part, fall within the scope of the present invention. These specific compositions, materials, and methods are not intended to limit the invention, but merely to illustrate specific embodiments falling within the scope of the invention. One skilled in the art may develop equivalent compositions, materials, and methods without the exercise of inventive capacity and without departing from the scope of the invention. It will be understood that many variations can be made in the procedures herein described while still remaining within the bounds of the present invention. It is the intention of the inventors that such variations are included within the scope of the invention.


EXAMPLES
Example 1: Hybridoma Development
1. Methods
1.1 Immunization and Serum Titer Determination
1.1.1 Immunogen and Immunization Strategies
Cell Immunization

CHO-S cells overexpressing human CD276 protein (UniProt ID: Q5ZPR3, i.e. CHO-S-hCD276) or mouse CD276 protein (UniProt ID: Q8VE98, i.e. CHO-S-hCD276) were used as immunogen.


Protein Immunization

Recombinant human CD276 protein (SEQ ID NO: 346): the recombinant human CD276 protein was prepared by digesting the human CD276 protein with enterokinase, and the extracellular domain of human CD276 was fused with 6×His tag and DDDDK (SEQ ID NO: 345).


Recombinant human CD276 protein (SEQ ID NO: 346):









LEVQVPEDPVVALVGTDATLCCSFSPEPGFSLAQLNLIWQLTDTKQLVHS





FAEGDQGSAYANRTALFPDLLAQGNASLRLQRVRVADEGSFTCFVSIRDF





GSAAVSLQVAAPYSKPSMTLEPNKDLRPGDTVTITCSSYQGYPEAEVFWQ





DGQGVPLTGNVTTSQMANEQGLFDVHSILRVVLGANGTYSCLVRNPVLQQ





DAHSSVTITPQRSPTGAVEVQVPEDPVVALVGTDATLRCSFSPEPGFSLA





QLNLIWQLTDTKQLVHSFTEGRDQGSAYANRTALFPDLLAQGNASLRLQR





VRVADEGSFTCFVSIRDFGSAAVSLQVAAPYSKPSMTLEPNKDLRPGDTV





TITCSSYRGYPEAEVFWQDGQGVPLTGNVTTSQMANEQGLFDVHSVLRVV





LGANGTYSCLVRNPVLQQDAHGSVTITGQPMTFPPEAHHHHHHDDDDK.






Balb/c and SJL mice were immunized as shown below. The primary immunization was followed by several boosts until animals developed satisfactory antiserum titers suitable for hybridoma development.




















Animal/
Group



Group
Immunogen
Route
Strain
size
Dosage




















1
CHO-S-hCD276 cells
Intraperitoneal
Balb/c
5
5 × 106




Injection (I.P.)


2
Recombinant human
hypodermic
Balb/c
5
100 μg



CD276 protein
injection (I.H.)


3
CHO-S-mCD276
I.P.
Balb/c
5
5 × 106


4
CHO-S-hCD276 cells
I.P.
SJL
5
5 × 106


5
Recombinant human
I.H.
SJL
5
100 μg



CD276 protein









1.1.2 Immunization Schedules
Immunization Schedule (Group 1)

















Day 0
Pre-bleed (15-30 μL serum/mouse)




Primary: 5 × 106 cell per mouse I.P.



Day 14
Boost 1: 5 × 106 cell per mouse I.P.




Test Bleed (15-30 μL serum/mouse) (TB1)




Test bleed FACS



Day 28
Boost 2: I.P., 5 × 106 cell per mouse I.P.



Day 38
Test Bleed (15-30 μL serum/mouse) (TB2)



Day 38
Test bleed FACS




Data analysis and phase conclusion



Day 39
Pre-fusion (final) Boost, I.H., 100 μg per mouse







Animals not selected for cell fusion will be maintained in cage and may be given additional boost immunizations.






Immunization Schedule (Group 2)

















Day 0
Pre-bleed (15-30 μL serum/mouse)




Primary: 100 μg/mouse I.H., CFA



Day 14
Boost 1: 100 μg/mouse I.H., IFA




Test Bleed (15-30 μL serum/mouse) (TB1)




Test bleed FACS



Day 28
Boost 2: I.H., 100 μg/mouse I.H., IFA



Day 38
Test Bleed (15-30 μL serum/mouse) (TB2)



Day 38
Test bleed FACS




Data analysis and phase conclusion



Day 42
Pre-fusion (final) Boost, I.P., 5 × 106 cell per mouse







Animals not selected for cell fusion will be maintained in cage and may be given additional boost immunizations.






Immunization Schedule (Group 3)

















Day 0
Pre-bleed (15-30 μL serum/mouse)




Primary: 5 × 106 cell per mouse I.P.



Day 14
Boost 1: 5 × 106 cell per mouse I.P.




Test Bleed (15-30 μL serum/mouse) (TB1)




Test bleed FACS



Day 28
Boost 2: I.P., 5 × 106 cell per mouse I.P.



Day 38
Test Bleed (15-30 μL serum/mouse) (TB2)



Day 38
Test bleed FACS




Data analysis and phase conclusion



Day 39
Pre-fusion (final) Boost, I.P., 5 × 106 cell per mouse







Animals not selected for cell fusion were maintained in cage and were given additional boost immunizations.






Immunization Schedule (Group 4)

















Day 0
Pre-bleed (15-30 μL serum/mouse)




Primary: 5 × 106 cell per mouse I.P.



Day 14
Boost 1: 5 × 106 cell per mouse I.P.




Test Bleed (15-30 μL serum/mouse) (TB1)




Test bleed FACS



Day 28
Boost 2: I.P., 5 × 106 cell per mouse I.P.



Day 38
Test Bleed (15-30 μL serum/mouse) (TB2)



Day 38
Test bleed FACS




Data analysis and phase conclusion



Day 42
Boost 2: I.P., 5 × 106 cell per mouse I.P.



Day 51
Test Bleed (15-30 μL serum/mouse) (TB2)



Day 51
Test bleed FACS




Data analysis and phase conclusion



Day 52
Pre-fusion (final) Boost, I.P., 5 × 106 cell per mouse







Animals not selected for cell fusion were maintained in cage and were given additional boost immunizations.






Immunization Schedule (Group 5)

















Day 0
Pre-bleed (15-30 μL serum/mouse)




Primary: 100 μg/mouse I.H., CFA



Day 14
Boost 1: 100 μg/mouse I.H., IFA




Test Bleed (15-30 μL serum/mouse) (TB1)




Test bleed FACS



Day 28
Boost 2: I.H, 100 μg/mouse I.H., IFA



Day 38
Test Bleed (15-30 μL serum/mouse) (TB2)



Day 38
Test bleed FACS



Day 42
Boost 2: I.H, 100 μg/mouse I.H., IFA



Day 51
Test Bleed (15-30 μL serum/mouse) (TB2)



Day 51
Test bleed FACS




Data analysis and phase conclusion



Day 68
Pre-fusion (final) Boost, I.H, 100 μg/mouse







Animals not selected for cell fusion were maintained in cage and were given additional boost immunizations.






1.1.3 Test Bleed Antiserum Analysis

Screening-Test bleeds were performed and evaluated by testing using FACS on CHO-S cell line stably over-expressing human and/or mouse CD276 (CHO-S-hCD276 and/or CHO-S-mCD276).


Screening-Test bleeds were performed and evaluated by testing using Elisa with extra-cellular domain of recombinant human CD276 protein.


1.2 Hybridoma Generation and Screening
1.2.1 Cell Fusion and Screening

Fusion—Splenocyte fusions were performed on the mice which responded the best to the immunizations as determined by test bleed FACS. The lymphocytes from spleens and lymph nodes were fused to a Sp2/0 cell line using an optimized electrofusion protocol. Multiple fusions were performed to ensure success of the cell fusion.


Screening and expansion—The fusion was plated (2×104 to 105 per well) into a stack of 96-well plates. Plates were monitored for growth and fed weekly. Wells with cell growth were screened by primary screening assays in 10-14 days with FACS and/or other feasible assays such as Elisa. Multiple fusions for each targeting antigen were performed and screened. The positive parental clones which showed positive binding with CHO-S-CD276 and positive Elisa signal from primary screening were expanded into 24-well plates for secondary screening.


Additional antibody screening-Following primary screening, positive parental clones expanded into 24-well plates were screened again by the assay described in the hybridoma screening funnel below.


Hybridomas of interest were chosen to proceed to subcloning.


1.2.2 Hybridoma Subcloning, Screening and Cryopreservation

Subcloning—The parental hybridomas with desired reactivity and isotypes from the screening funnel above were then subcloned by multiple rounds of limiting dilution or single cell sorting until monoclones were obtained.


Screening & Expansion—The subcloning plates were screened by protein or cell-based Elisa, and the subclones with good binding ability were expanded to 24-wells for confirmation tests. The specificity and cross-reactivity of these subclones were confirmed with FACS analysis. Briefly, parental CHO-S cells, CHO-S-hCD276, CHO-S cell line stably over-expressing Macaca fascicularis CD276, CHO-K1 S, cell line stably over-expressing mouse CD276 were incubated with antibodies produced by each subclone respectively. Fluorescent dye-conjugated secondary antibody was used to detect the binding of the primary antibody with the cells. Median fluorescence intensity was measured by FACS analysis.


Cryopreservation—The desired subclonal cell lines were sequenced and further expanded into culture flasks for cryopreservation. 4-6 vials per cell line at 0.5-13.0×106 cells/vial were initially cryopreserved. Master cell bank and working cell bank were established for the selected most valuable cell lines if desired.


2. Results

We discovered 43 antibodies with unique sequences showing positive binding with CHO-S cell stably over-expressing human CD276 protein (CHO-S-hCD276) but not binding to parental CHO-S cells, suggesting these antibodies are human CD276 recognizing antibody. Among which 42 antibodies could bind with cynomolgus monkey CD276, and 11 antibodies could bind with mouse CD276 protein. The MFI of the mouse antibodies staining CHO-S, CHO-S-hCD276, CHO-S-mCD276, CHO-S-Macaca fascicularis CD276 (CHO-S-cynoCD276), detected by FACS were summarized in the table below (Table 5).









TABLE 5







MFI of antibodies binding with different cell lines












FACS
FACS MFI
FACS MFI
FACS MFI



MFI
(CHO-S-
CHO-S-
CHO-S-


Clone
(CHO-S)
hCD276)
mCD276
cynoCD276














15-G1-D1-E3
1585
62545
6610
99442


28-G2-E6-B10
1267
56316
2077
40831


6-D8-E7-A11
2571
37901
92619
100797


8-B4-F5-E11
1574
40419
7366
58650


13-A8-C4-G1
999
54074
6198
95808


6-F3-G2-G1
1441
37392
6978
113858


15-C8-B5-G7
1114
36640
5734
42958


3-G7-D8-D3
1331
82411
1291
6422


14-E7-G9-D4
1331
78067
1304
61808


6-H11-G5-D8
1327
112516
1358
30365


7-E1-F8-F6
1345
6990
1309
5590


9-E8-F9-C10
1309
7607
1951
5705


3-C2-C3-E7
1188
38810
2770
2106


27-F8-E10-E11
1322
15962
1349
80481


9-G2-H6-E4
1309
49603
27620
5404


25-D3-G4-C6
1331
5941
1372
5386


27-E7-D8-C7
1313
94678
1587
87885


2-A7-B10-A3
1322
58948
2039
56030


18-F9-D8-G7
1309
126666
20645
83534


10-B9-D10-A12
1280
399656
3171
10125


24-C10-F9-G7
1342
85105
1184
15198


20-A2-D10-G8
1184
77149
1255
9025


3-F2-E7-F9
1250
52275
1141
35661


5-D1-G6-D9
1349
45271
1529
62228


23-F10-G4-F11
1327
127095
1300
36702


16-C6-F7-F5
1276
141395
1833
19524


22-E11-C3-F2
1188
74329
1667
56507


11-C12-F4-F6
1345
41880
1340
5137


16-G3-D10-C10
1336
23162
1322
6188


26-D2-D6-B12
1345
47467
1313
63076


21-B3-B1-H5
1304
71491
1345
20230


30-C7-C11-D4
1327
138317
8222
96294


11-G10-B4-B11
1307
32768
2798
26386


20-F8-B5-G2
1322
88781
67038
51137


9-B9-H11-G7
1041
96785
1356
145769


9-G12-D6-A11
1066
53167
1422
35661


10-G6-C4-B2
1340
5647
17431
4322


8-C3-E3-F3
1340
63936
1322
12053


30-E2-G7-G7
1322
46988
1296
35122


20-C5-D7-D3
1309
77017
1345
13206


13-E4-G9-A4
1209
148759
1370
16822


25-C8-D7-C5
1188
147755
1157
39074


4-D5-B9-B11
1225
144785
2099
148256









Example 2: Antibody Characterization: Affinity
1. Methods
1.1 Cell Based Binding Affinity on SKOV3 Cancer Cell Line

Sequences of 31 mouse antibodies from Table 5 were selected to generate and produce human IgG1 chimeric antibodies. The binding affinity of these antibodies and bench mark antibody, Enoblituzumab (see U.S. Pat. No. 8,802,091, MGA271, specifically with a construct designated as hBRCA84D-2) and MGC018 (an antibody-drug-conjugate, in which the mAb MGA017 (human IgG1) is conjugated via a cleavable linker to the prodrug seco-DUocarmycin hydroxyBenzamide Azaindole (DUBA), an alkylating agent that can damage DNA in both dividing and non-dividing cells, thereby causing cell death) with human patient derived ovarian cancer cell line, SKOV3, was determined by FACS analysis.


The protocol for FACs analysis is described as follows:

    • 1. Digested cells using Trypsin (1×); Centrifuged the harvested cells at 300 g for 3 min and discarding the supernatant.
    • 2. Washed the cells 2 times with FACS buffer by centrifuging at 300 g for 3 min and discarding the supernatant.
    • 3. Resuspended the cells, and 2*105 cell/well was seeded into the assay plate in 50 μl FACS buffer, then added 50 μl primary antibody (primary antibody final concentration: (5.00, 1.67, 0.56, 0.19, 0.06, 0.02, 0.01, 0.00 μg/ml or 20.00, 6.67, 2.22, 0.74, 0.25, 0.08, 0.03, 0.00 μg/ml). Incubated at 4° C. for 1 hour.
    • 4. Washed the cells twice by using the condition in step 2. Resuspended the cells with 100 μl/well diluted 2nd antibody, incubated at 4° C. for 1 hour in the dark.
    • 5. Washed the cells twice by using the condition in step 2. Resuspended the cells with 100 μl/well FACS buffer. Kept the cells in dark for FACS analysis.


The binding affinity of the selected antibodies on SKOV3 are higher, lower or comparable with bench mark antibody Enoblituzumab (see Table 6 and FIG. 1).









TABLE 6







Binding affinity of the chimeric antibodies on SKOV3










SKOV3











Number
Name
MFI (Max)
EC50 (μg/ml)













1
igG
114.8
/


2
Enoblituzumab
830.3
0.9847


3
MGC018
2545
0.3847


4
15-G1-D1-E3
3186
0.8113


5
6-D8-E7-A11
2828
0.4022


6
15-C8-B5-G7
2137
0.2929


7
3-G7-D8-D3
1214
0.5095


8
14-E7-G9-D4
2726
1.618


9
6-H11-G5-D8
199.6
1.78


10
7-E1-F8-F6
3378
0.9823


11
3-C2-C3-E7
3703
1.433


12
27-F8-E10-E11
3224
2.26


13
9-G2-H6-E4
291.7
3.659


14
25-D3-G4-C6
3447
1.267


15
27-E7-D8-C7
4750
0.5425


16
18-F9-D8-G7
4610
0.2857


17
10-B9-D10-A12
3879
2.082


18
20-A2-D10-G8
3112
0.7906


19
23-F10-G4-F11
6725
4.425


20
16-C6-F7-F5
5354
0.1858


21
22-E11-C3-F2
5545
0.5228


22
16-G3-D10-C10
3176
1.311


23
21-B3-B1-H5
2718
0.7228


24
30-C7-C11-D4
4266
0.2821


25
11-G10-B4-B11
3747
0.5358


26
20-F8-B5-G2
3012
1.109


27
10-G6-C4-B2
5640
0.8215


28
8-C3-E3-F3
2883
0.6432


29
30-E2-G7-G7
5628
0.814


30
20-C5-D7-D3
2308
0.941


31
13-E4-G9-A4
3076
1.775


32
25-C8-D7-C5
3483
2.031









2. Protein Based Affinity Test by Biacore (ChemPartner)
Test Condition:





    • Analyte: B7H3

    • Running buffer: HBS-EP+

    • Flow Rate: 30 μL/min

    • Capture: Abs, 10 μL/min for 60 s

    • Injection of serial diluted B7H3

    • Contact time: 180 s

    • Dissociation time: 400 s

    • Regeneration: pH1.5 Gly, 30 μL/min for 30 s

    • Method: Multiple cycle kinetics/affinity using capture

    • Machine Model: Biacore 8K (GE)

    • Analysis Temperature: 25° C.












TABLE 7







shows the binding affinity of the chimeric antibodies on hB7H3


by Biacore (ChemPartner)















Kinetics
Capture 1
Analyte 1
Kinetics





Entry
model
Solution
Solution
Chi2 (RU2)
ka (1/Ms)
kd (1/s)
KD (M)

















1
1:1 binding
2 μg/ml 15-
HUMAN B7H3
5.91E−01
5.50E+05
2.11E−04
3.83E−10




G1-D1-E3







2
1:1 binding
1 μg/ml 6-
HUMAN B7H3
8.17E−01
4.64E+05
3.48E−04
7.49E−10




D8-E7-A11







3
1:1 binding
2 μg/ml 15-
HUMAN B7H3
3.70E−01
4.92E+05
1.96E−04
3.99E−10




C8-B5-G7







4
1:1 binding
2 μg/ml 7-
HUMAN B7H3
1.97E−01
2.60E+05
2.22E−04
8.55E−10




E1-F8-F6







5
1:1 binding
2 μg/ml 27-
HUMAN B7H3
2.34E−01
2.78E+05
1.73E−04
6.21E−10




F8-E10-E11







6
1:1 binding
2 μg/ml 25-
HUMAN B7H3
1.42E−01
1.08E+05
2.50E−04
2.31E−09




D3-G4-C6







7
1:1 binding
1 μg/ml 18-
HUMAN B7H3
8.59E−01
4.89E+05
2.39E−04
4.89E−10




F9-D8-G7







8
1:1 binding
2 μg/ml 20-
HUMAN B7H3
8.74E−01
5.08E+05
2.82E−04
5.55E−10




A2-D10-G8







9
1:1 binding
2 μg/ml 16-
HUMAN B7H3
2.15E+00
3.77E+05
2.43E−04
6.45E−10




C6-F7-F5







10
1:1 binding
2 μg/ml 16-
HUMAN B7H3
1.29E−01
1.85E+05
2.14E−04
1.16E−09




G3-D10-C10







11
1:1 binding
1 μg/ml 10-
HUMAN B7H3
1.80E−01
2.52E+05
1.98E−04
7.85E−10




G6-C4-B2







12
1:1 binding
1 μg/ml 8-
HUMAN B7H3
4.26E−01
9.90E+05
4.40E−04
4.44E−10




C3-E3-F3







13
1:1 binding
2 μg/ml 20-
HUMAN B7H3
5.33E−01
6.45E+05
4.16E−04
6.44E−10




C5-D7-D3







14
1:1 binding
2 μg/ml 25-
HUMAN B7H3
3.97E−01
2.03E+05
2.43E−04
1.20E−09




C8-D7-C5







15
1:1 binding
1 μg/ml 10-
HUMAN B7H3
6.25E−01
3.75E+05
2.82E−04
7.52E−10




B9-D10-A12







16
1:1 binding
1 μg/ml
HUMAN B7H3
5.98E−01
1.28E+05
4.86E−04
3.80E−09




Enoblituzumab







17
1:1 binding
2 μg/ml
HUMAN B7H3
6.03E−02
8.89E+05
4.08E−04
4.59E−10




MGC018









3. B7H3's Expression Pattern on Several Cancer Cell Lines

B7H3 expression were detected by FACS with 6-D8-E7-A11. High expression level of B7H3 on several cancer cell lines, such as BxPC3 (Pancreatic), MCF7 (Breast), Dentroit562 (Head and neck), RKO (Colon) and SUN620 (Gastric), were found (see FIG. 2).


Example 3. Antibody Characterization: ADCC
1. Methods

In order to determine the ADCC of the anti-CD276 antibodies, 1×105/well SKOV3 were seeded to 96 wells Flat-bottom sterile plate, then 2×104 Jurkat-NFAT-Luciferase-CD16 were added as effector cell. After that, serial diluted antibodies were added to each well and the plate were incubated at 37° C., 5% CO2 for 18 hours. Finally, the luciferase activity was detected to evaluate the ADCC activity of antibodies.


2. Result

All our antibodies showed potent ADCC effect on SKOV3 cells (a human ovarian cancer cell line). Some of the antibodies showed lower or comparable EC50 compared with bench mark antibody, Enoblituzumab (Table 8 and FIG. 3), indicating that they are more potent in mediating ADCC effect on SKOV3 cells than Enoblituzumab (MGA271).









TABLE 8







EC50 of antibody induced ADCC effect on SKOV3









EC50 (μg/ml)














Enoblituzumab
0.08636



9-E8-F9-C10
4.052



10-G6-C4-B2
0.2369



18-F9-D8-G7
0.5032



27-E7-D8-C7
0.1035



3-C2-C3-E7
0.1864



16-C6-F7-F5
0.006641



22-E11-C3-F2
0.01792



30-E2-G7-G7
0.2473



23-F10-G4-F11
0.1367



11-G10-B4-B11
17.34



30-C7-C11-D4
0.03268



5-D1-G6-D9
1.553



20-F8-B5-G2
3.013



9-G2-H6-E4
13.6



10-B9-D10-A12
0.2585



20-A2-D10-G8
0.2625



20-C5-D7-D3
0.06897



13-E4-G9-A4
0.8762



25-C8-D7-C5
0.1228



16-G3-D10-C10
0.04186



21-B3-B1-H5
0.6478



8-C3-E3-F3
0.1111



15-G1-D1-E3
0.06548



15-C8-B5-G7
0.6968



27-F8-E10-E11
0.02385



25-D3-G4-C6
0.03723



2-A7-B10-A3
4.207



3-G7-D8-D3
0.008984



14-E7-G9-D4
0.2516



7-E1-F8-F6
0.01771



6-D8-E7-A11
0.06677










Example 4. Antibody Characterization: CDC
1. Methods

In order to determine the CDC of the anti-CD276 antibodies, CHO-S-hCD276 cells were resuspended in cell culture medium at 4E5 cells/mL and were then added into a 96-well opaque wall plate at 50 μL/well. Anti-CD276 antibodies were diluted with complete F-12K medium and added to the 96-well opaque wall plate at 50 μL/well. Human serum complement was diluted with cell culture medium and was added to the same plate at 50 μL/well. The mixture was incubated for 2 hours in a CO2 incubator at 37° C. CellTiter-Glo reagent for determining the cell cytotoxicity was added at 50 μL/well and the mixture was incubated for 10 mins at R.T. Luminescence signal of viable cells on a microplate reader was recorded.


2. Result

All the anti-CD276 antibodies showed potent CDC effect on CHO-S-hCD276 cells and lower EC50 compared with benchmark antibody, Enoblituzumab (MGA271) (see Table 9 and FIG. 4).









TABLE 9







Max CHO-S-hCD276 killing percentage and


EC50 of antibody induced CDC effect










EC50 (nM)
Top cytotoxicity (%)















18-F9-D8-G7
2.441
70.33



30-C7-C11-D4
3.215
60.27



10-G6-C4-B2
2.738
93.53



16-C6-F7-F5
1.284
92.09



15-C8-B5-G7
7.537
86.1



7-E1-F8-F6
1.69
91.89



25-D3-G4-C6
2.413
89.7



MGA271-WT Fc
8.913
19.63



20-A2-D10-G8
1.922
85.07



16-G3-D10-C10
1.428
93.56



25-C8-D7-C5
2.417
91.37



6-D8-E7-A11
1.575
92.45



MGC018
1.672
93.32



MGA271
7.28
80.09



MGA271-WT Fc
9.64
19.77










Example 5. Antibody Characterization: Indirect ADC Cytotoxicity
1. Methods

Fab-ZAP is a chemical conjugate of goat anti-human monovalent antibody (a secondary antibody) and the ribosome-inactivating protein, saporin. Fab-ZAP is used to determine the internalization ability of antibodies. In this assay, 80 μL SKOV-3 cells were plated at 2000 cells/well in a 96-well plate and incubated overnight at 37° C. Anti-CD276 antibodies were then added at 40 μL/well. Fab-ZAP human dilution were added at 40 μL/well and incubated for 96 hours in a CO2 incubator at 37° C. CellTiter-Glo reagent for determining the cell cytotoxicity were added at 100 μL/well and incubated for 10 mins at R.T. Luminescence signal of viable cells on a microplate reader were recorded.


2. Result

All the anti-CD276 antibodies showed potent indirect ADC effect on SKOV3 cells, with lower or comparable IC50 compared with bench mark antibody, MGC018 (Table 10, FIG. 5), indicating that they are potential candidates for making ADCs.









TABLE 10







IC50 of indirect ADC cytotoxicity on SKOV3









IC50 (nM)














MGC018
0.013



6-D8-E7-A11
0.008



15-C8-B5-G7
0.008



7-E1-F8-F6
0.028



25-D3-G4-C6
0.023



18-F9-D8-G7
0.014



10-B9-D10-A12
0.021



20-A2-D10-G8
0.007



16-C6-F7-F5
0.009



22-E11-C3-F2
0.016



10-G6-C4-B2
0.008



8-C3-E3-F3
0.012



20-C5-D7-D3
0.007



13-E4-G9-A4
0.021



25-C8-D7-C5
0.018










Example 6. Antibody In Vivo Efficacy in the Treatment of Subcutaneous MC-38-hCD276 Murine Colon Carcinoma in Female C57BL/6 Mice
1. Study Design and Methods

Several monoclonal antibodies with mouse IgG2a Fc were constructed and expressed for the in vivo efficacy study.

    • 1. The MC-38-hCD276 (B7H3) tumor cells were maintained in vitro with DMEM medium supplemented with 10% fetal bovine serum at 37° C. in an atmosphere of 5% CO2 in air. The cells in exponential growth phase were harvested and quantitated by cell counter before tumor inoculation.
    • 2. Each mouse was inoculated subcutaneously in the right rear flank region with MC-38-hCD276 (B7H3) tumor cells (1×10{circumflex over ( )}6) in 0.1 ml of PBS for tumor development. The date of randomization was denoted as day 0, and dosing starts from day 0.
    • 3. The randomization will start when the mean tumor size reaches approximately 50-60 mm3. 60 mice were enrolled in this study. All animals were randomly allocated to 7 study groups. Randomization was performed based on randomized block design.
    • 4. Tumor volumes were measured twice per week in two dimensions using a caliper, and the volume were expressed in mm3 using the formula: V=(L×W×W)/2, where V is tumor volume, L is tumor length (the longest tumor dimension) and W is tumor width (the longest tumor dimension perpendicular to L). Dosing as well as tumor size and body weight measurements were conducted in a Laminar Flow Cabinet (see Table 11, FIG. 6).
    • 5. Atezolizumab (an anti-PD-L1 antibody, also named Tecentriq or MPDL3280A, see WO2010077634A1) and Antengene-084M (MGA271's Fab sequence (see U.S. Pat. No. 8,802,091B) constructed with mouse IgG2a) were used as control.









TABLE 11







Study design for in vivo efficacy test.





















Dose level
Dosing
Dosing

Dosing




Mouse
Tumor

(mg/kg) or
Solution
Volume

Frequency &


Group
No.
Strain
Model
Treatment
(mg/kg)
(mg/ml)
(μL/g)
ROA
Duration





1
6
C57BL/6
MC-38-
Mouse IgG2A
5
0.5
10
i.p.
Q3D × 5 doses





hCD276








2
6
C57BL/6
MC-38-
Atezolizumab
5
0.5
10
i.p.
Q3D × 5 doses





hCD276








3
6
C57BL/6
MC-38-
16-C6-F7-F5
5
0.5
10
i.p.
Q3D × 5 doses





hCD276
mouse IgG2a







4
6
C57BL/6
MC-38-
25-C8-D7-C5
5
0.5
10
i.p.
Q3D × 5 doses





hCD276
mouse IgG2a







5
6
C57BL/6
MC-38-
30-C7-C11-D4
5
0.5
10
i.p.
Q3D × 5 doses





hCD276
mouse IgG2a







6
6
C57BL/6
MC-38-
18-F9-D8-G7
5
0.5
10
i.p.
Q3D × 5 doses





hCD276
mouse IgG2a







7
6
C57BL/6
MC-38-
6-D8-E7-A11
5
0.5
10
i.p.
Q3D × 5 doses





hCD276
mouse IgG2a







8
6
C57BL/6
MC-38-
10-G6-C4-B2
5
0.5
10
i.p.
Q3D × 5 doses





hCD276
mouse IgG2a







9
6
C57BL/6
MC-38-
Antengene-
5
0.5
10
i.p.
Q3D × 5 doses





hCD276
084M mouse











IgG2a









2. Result

As shown in FIG. 6, some of the anti-CD276 antibodies showed potent in vivo efficacy. In particular, 25-C8-D7-C5 mouse IgG2a showed higher tumor inhibition than Antengene-084M mouse IgG2a.


Example 7: ADC In Vivo Efficacy Test of the Antibodies
1. Study Design and Methods

To evaluate the ADC potential of the antibodies, antibody conjugations with VC-MMAE in ChemPartner were performed. A serial of VC-MMAE conjugated antibodies were obtained. The details are shown in Table 12.









TABLE 12







Summary of the antibody conjugations













Concen-

SEC
Endotoxin




tration
Qty
Aggregation
level


ADC Name
(mg/mL)
(mg)
(%)
(EU/mg)
HIC-DAR















MGC018
3.865
11.6
1.04
0.23
4.48


16-C6-F7-F5
3.680
9.6
1.07
0.34
4.45


20-A2-D10-G8
3.287
9.9
0.26
0.27
4.15


6-D8-E7-A11
4.041
8.1
1.52
0.41
4.18


10-G6-C4-B2
3.706
16.7
0.62
0.48
4.20


15-C8-B5-G7
3.627
15.2
0.76
0.66
4.42


18-F9-D8-G7
3.900
15.6
0.79
0.75
4.04


higG
3.825
8.0
1.09
0.29
4.39









Each Balb/c nude mouse for Calu-6 study was inoculated subcutaneously in the right front flank region with Calu-6 tumor cells (5×106) in 0.1 ml of PBS for tumor development. The randomization starts when the mean tumor size reaches approximately 122 mm3. 60 mice were enrolled in the study. The date of randomization was denoted as day 0, dosing starts from day 0.


2. Results

The therapeutic efficacy of test articles in the treatment of subcutaneous human lung cancer Calu-6 in Balb/c nude mice was investigated in this study. No obvious body weight loss, mortality or toxic response was observed in the designed dosing regimens during the efficacy study. At day 24, MGC018, 10-G6-C4-B2, 16-C6-F7-F5, 15-C8-B5-G7 and 18-F9-D8-G7 at 3 mg/kg as a single agent show a significant anti-tumor efficacy against Calu-6 model in Balb/c nude mice, respectively. The results are shown in FIG. 7 and Table 13.









TABLE 13







Antitumor Activity of Test Compounds in Subcutaneous


Calu-6 Model in Balb/c Nude Mice














Tumor Size (mm3) a
T/C (%) on
TGI (%) on



Group
Treatment Description
on day 24
day 24
day 24
P value b















1
IgG
2103.52 ± 236.00





2
MGC018
215.48 ± 53.71
10.24
89.76
<0.0001


3
10-G6-C4-B2
229.10 ± 66.60
10.89
89.11
<0.0001


4
16-C6-F7-F5
 398.44 ± 116.04
18.94
81.06
0.00159


5
20-A2-D10-G8
504.02 ± 62.98
23.96
76.04
0.0765


6
15-C8-B5-G7
 561.24 ± 285.12
26.68
73.32
0.00174


7
18-F9-D8-G7
418.59 ± 75.48
19.90
80.10
0.0126


8
6-D8-E7-A11
493.00 ± 61.89
23.44
76.56
0.0677





Note:



a Mean ± SEM;




b TGI, T/C and p values were compared with group 1 tumor volume on day 24 by using Dunnett's tests.







Example 8: T Cell Activation (MLR Assay) Test of the Antibodies
1. Study Design and Methods
DC Induction

Monocyte cells were re-suspended at 5×106 in 3 ml complete medium supplemented with 2 U/ml of dendritic cell culture factor and then culture cells in 6-well plate. At the second day, 2 ml/well of fresh complete medium supplemented with 2 U/ml of dendritic cell culture factor were added for another three days culture. Then monocytes differentiated into immature dendritic cells (iDC). After stimulated 48 hours with 2 U/ml of dendritic cell mature factor, iDCs would differentiate into mature dendritic cells.


Antibody Digestion

Combined 25 μg of hIgG1 and 3 μl of 10× Glyco Buffer, and then added PBS to make a 30 μl total reaction volume. 1 μl of IdeZ Protease was added, then incubated at 37° C. for 30 minutes. 10 μl protein A/G beads were added in 1 mL PBS, washed 2 times. The beads were resuspended with reaction solution from the above step.


The tube was put on a magnet for 1 min RT, the F(ab)2 is in supernatant and the Fc was captured by beads.


MLR Assay

0.2 million cells/well T cells and 0.02 million cells/well mDCs were seeded.


Cells were treated PBS, IgG1, 25-C8-D7-C5, 30-C7-C11-D4, BMK (MGA271) or their Fab (final concentration 5 μg/ml). After 24 hours, supernatants were collected and human IL-2 and IFNγ was tested with Elisa.


2. Results

As shown in FIGS. 8 and 9, 30-C7-C11-D4 can activate T cell activation while 25-C8-D7-C5 and BMK (MGA271) cannot.


Example 9: Antibody Humanization and PTM Optimization
9.1 Cell-Based Affinity Test of the Humanized Antibodies by FACS

10-G6-C4-B2 and 30-C7-C11-D4 were chosen to perform humanization and PTM optimization. The affinity of humanized candidates and optimized PTM sequences were evaluated by FACS.


The results are shown in FIGS. 10 and 11. All sequence showed comparable affinity with parental antibody.


9.2 Protein Based Affinity Test by Biacore (ChemPartner)
Test Condition:

Analyte: B7H3. Running buffer: HBS-EP+. Flow Rate: 30 L/min. Capture: Abs, 10 μL/min for 60 s. Injection of serial diluted B7H3. Contact time 180 s, dissociation time 400 s. Regeneration: pH1.5 Gly, 30 μL/min for 30 s. Method: Multiple cycle kinetics/affinity using capture. Machine Model: Biacore 8K (GE). Analysis Temperature: 25° C.


The results are shown in Table 14.









TABLE 14







Binding affinity of the humanized antibodies on hB7H3 by


Biacore (ChemPartner)













Kinetics

Analyte 1
Kinetics





model
Capture 1 Solution
Solution
Chi2 (RU2)
ka (1/Ms)
kd (1/s)
KD (M)





1:1 binding
10-G6-C4-B2
B7H3
2.05E−01
2.16E+05
8.97E−05
4.15E−10


1:1 binding
10-G6-C4-B2_hVH2-
B7H3
1.10E−01
8.53E+04
7.26E−05
8.51E−10



VL_1_PTM







1:1 binding
10-G6-C4-B2_hVH3-
B7H3
1.61E−01
1.18E+05
1.02E−06
8.70E−12



VL3_PTM







1:1 binding
10-G6-C4-B2_h_VH4-
B7H3
1.16E−01
8.96E+04
1.55E−04
1.73E−09



VL1_PTM







1:1 binding
10-G6-C4-B2_hVH4-
B7H3
1.21E−01
5.27E+04
7.12E−05
1.35E−09



VL2_PTM







1:1 binding
10-G6-C4-B2_hVH5-
B7H3
1.11E−01
1.47E+05
1.37E−05
9.29E−11



VL_1_PTM







1:1 binding
10-G6-C4-B2_hVH5-
B7H3
2.61E−01
1.46E+05
1.01E−06
6.92E−12



VL3_PTM









9.3 ADC Therapeutic Capability Test of the Humanized 10-G6-C4-B2 Antibodies In Vivo

The in vivo ADC therapeutic capability of the humanized 10-G6-C4-B2 antibodies were evaluated. Antibody conjugations with VC-MMAE in ChemPartner were constructed. A serial of VC-MMAE conjugated antibodies were obtained, the details of which were shown in Table 15.









TABLE 15







Summary of the antibody conjugations















SEC





Concen-

Aggre-

Endotoxin



tration
Qty
gation
HIC-
Level


ADC Name
(mg/mL)
(mg)
(%)
DAR
(EU/mg)















10-G6-C4-B2_h_VH2-
3.073
6.88
0.85
4.69
0.039


VL1_PTM


10-G6-C4-B2_hVH3-
3.186
8.19
0.5
4.44
0.028


VL3_PTM


10-G6-C4-B2_hVH4-
3.181
7.60
1.37
4.57
0.047


VL1_PTM


10-G6-C4-B2_hVH4-
2.950
7.82
1.82
4.22
0.041


VL2_PTM


10-G6-C4-B2_hVH5-
1.834
1.47
1.56
4.33
Not tested


VL1_PTM


10-G6-C4-B2_hVH5-
3.251
7.90
0.2
4.6
0.055


VL3_PTM


IgG
3.286
7.85
1.19
4.63
0.037


10-G6-C4-B2
2.506
4.21
0.43
4.35
0.036









Each Balb/c nude mouse for Calu-6 study was inoculated subcutaneously in the right front flank region with Calu-6 tumor cells (5×106) in 0.1 ml of PBS for tumor development. The randomization starts when the mean tumor size reaches approximately 122 mm3. 60 mice were enrolled in the study. The date of randomization was denoted as day 0, dosing starts from day 0.


The therapeutic efficacy of test articles in the treatment of subcutaneous human lung cancer Calu-6 in Balb/c nude mice was investigated in this study. No obvious body weight loss, mortality or toxic response was observed in the designed dosing regimens during the efficacy study.


The results are shown in FIG. 12 and Table 16. At day 26, almost all the test articles at 3 mg/kg as a single agent show a significant anti-tumor efficacy against Calu-6 model in Balb/c nude mice, respectively.









TABLE 16







Antitumor activity of test compounds in subcutaneous


Calu-6 model in Balb/c nude mice













T/C
TGI




Tumor Size (mm3) a
(%) on
(%) on


Treatment Description
on day 26
day 26
day 26
P value b





igG, 3 mg/kg, QWx4 doses
2823.12 ± 361.18(6)





10-G6-C4-B2, 3 mg/kg, QWx4
752.77 ± 33.24(6)
26.66
73.34
>0.05


doses



(0.0645)


10-G6-C4-B2_hVH2-
 936.63 ± 227.54(6)
33.18
66.82
<0.05


VL1_PTM, 3 mg/kg, QWx4



(0.0421)


doses


10-G6-C4-B2_hVH3-
544.41 ± 49.50(6)
19.28
80.72
<0.001


VL3_PTM, 3 mg/kg, QWx4



(4.35E−05)


doses


10-G6-C4-B2_hVH4-
633.69 ± 61.73(6)
22.45
77.55
<0.001


VL1_PTM, 3 mg/kg, QWx4



(0.000727)


doses


10-G6-C4-B2_hVH4-
744.98 ± 69.83(6)
26.39
73.61
<0.05


VL2_PTM, 3 mg/kg, QWx4



(0.0396)


doses


10-G6-C4-B2_hVH5-
 856.17 ± 216.11(6)
30.33
69.67
<0.01


VL1_PTM, 3 mg/kg, QWx4



(0.00691)


doses


10-G6-C4-B2_hVH5-
 595.32 ± 124.15(6)
21.09
78.91
<0.001


VL3_PTM, 3 mg/kg, QWx4



(0.000593)


doses





Note:


Mean ± SEM; TGI, T/C and p values were compared with group 1 tumor volume on day 26 using Kruskal-Wallis test. . .





Claims
  • 1-3. (canceled)
  • 4. An antibody or antigen-binding fragment thereof, comprising: a) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 1, SEQ ID NO: 2, and SEQ ID NO: 3; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 4, SEQ ID NO: 5, and SEQ ID NO: 6;b) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14;c) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 17, SEQ ID NO: 18, and SEQ ID NO: 19; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 20, SEQ ID NO: 21 and SEQ ID NO: 22;d) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 25, SEQ ID NO: 26, and SEQ ID NO: 27; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 28, SEQ ID NO: 29, and SEQ ID NO: 30;e) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 33, SEQ ID NO: 34, and SEQ ID NO: 35; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 36, SEQ ID NO: 37, and SEQ ID NO: 38;f) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:41, SEQ ID NO: 42, and SEQ ID NO: 43; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO:46;g) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:49, SEQ ID NO: 50, and SEQ ID NO: 51; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 52, SEQ ID NO: 53, and SEQ ID NO: 54;h) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 57, SEQ ID NO: 58, and SEQ ID NO: 59; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 60, SEQ ID NO: 61, and SEQ ID NO: 62;i) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 65, SEQ ID NO: 66, and SEQ ID NO: 67; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 68, SEQ ID NO: 69, and SEQ ID NO: 70;j) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 73, SEQ ID NO: 74, and SEQ ID NO: 75; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 76, SEQ ID NO: 77, and SEQ ID NO: 78;k) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 81, SEQ ID NO: 82, and SEQ ID NO: 83; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 84, SEQ ID NO: 85, and SEQ ID NO: 86;l) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 89, SEQ ID NO: 90, and SEQ ID NO: 91; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 92, SEQ ID NO: 93, and SEQ ID NO: 94;m) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 97, SEQ ID NO: 98, and SEQ ID NO: 99; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 100, SEQ ID NO: 101, and SEQ ID NO: 102;n) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 105, SEQ ID NO: 106, and SEQ ID NO: 107; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 108, SEQ ID NO: 109 and SEQ ID NO: 110;o) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 113, SEQ ID NO: 114, and SEQ ID NO: 115; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 116, SEQ ID NO: 117, and SEQ ID NO: 118;p) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 121, SEQ ID NO: 122, and SEQ ID NO: 123; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 124, SEQ ID NO: 125, and SEQ ID NO: 126;q) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:129, SEQ ID NO: 130, and SEQ ID NO: 131; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 132, SEQ ID NO: 133, and SEQ ID NO:134;r) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:137, SEQ ID NO: 138, and SEQ ID NO: 139; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 140, SEQ ID NO: 141, and SEQ ID NO: 142;s) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 145, SEQ ID NO: 146, and SEQ ID NO: 147; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 148, SEQ ID NO: 149, and SEQ ID NO: 150;t) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 153, SEQ ID NO: 154, and SEQ ID NO: 155; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 156, SEQ ID NO: 157, and SEQ ID NO: 158;u) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 161, SEQ ID NO: 162, and SEQ ID NO: 163; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 164, SEQ ID NO: 165, and SEQ ID NO: 166;v) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 169, SEQ ID NO: 170, and SEQ ID NO: 171; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 172, SEQ ID NO: 173, and SEQ ID NO: 174;w) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 177, SEQ ID NO: 178, and SEQ ID NO: 179; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 180, SEQ ID NO: 181, and SEQ ID NO: 182;x) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 185, SEQ ID NO: 186, and SEQ ID NO: 187; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 188, SEQ ID NO: 189, and SEQ ID NO: 190;y) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 193, SEQ ID NO: 194, and SEQ ID NO: 195; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 196, SEQ ID NO: 197 and SEQ ID NO: 198;z) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 201, SEQ ID NO: 202, and SEQ ID NO: 203; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 204, SEQ ID NO: 205, and SEQ ID NO: 206;aa) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 209, SEQ ID NO: 210, and SEQ ID NO: 211; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 212, SEQ ID NO: 213, and SEQ ID NO: 214;bb) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:217, SEQ ID NO: 218, and SEQ ID NO: 219; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 220, SEQ ID NO: 221, and SEQ ID NO:222;cc) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:225, SEQ ID NO: 226, and SEQ ID NO: 227; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 228, SEQ ID NO: 229, and SEQ ID NO: 230;dd) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 233, SEQ ID NO: 234, and SEQ ID NO: 235; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 236, SEQ ID NO: 237, and SEQ ID NO: 238;ee) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 241, SEQ ID NO: 242, and SEQ ID NO: 243; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 244, SEQ ID NO: 245, and SEQ ID NO: 246;ff) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 249, SEQ ID NO: 250, and SEQ ID NO: 251; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 252, SEQ ID NO: 253, and SEQ ID NO: 254;gg) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 257, SEQ ID NO: 258, and SEQ ID NO: 259; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 260, SEQ ID NO: 261, and SEQ ID NO: 262;hh) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 265, SEQ ID NO: 266, and SEQ ID NO: 267; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 268, SEQ ID NO: 269, and SEQ ID NO: 270;ii) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 273, SEQ ID NO: 274, and SEQ ID NO: 275; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 276, SEQ ID NO: 277, and SEQ ID NO: 278;jj) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 281, SEQ ID NO: 282, and SEQ ID NO: 283; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 284, SEQ ID NO: 285 and SEQ ID NO: 286;kk) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 289, SEQ ID NO: 290, and SEQ ID NO: 291; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 292, SEQ ID NO: 293, and SEQ ID NO: 294;ll) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 297, SEQ ID NO: 298, and SEQ ID NO: 299; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 300, SEQ ID NO: 301, and SEQ ID NO: 302;mm) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:305, SEQ ID NO: 306, and SEQ ID NO: 307; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 308, SEQ ID NO: 309, and SEQ ID NO:310;nn) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO:313, SEQ ID NO: 314, and SEQ ID NO: 315; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 316, SEQ ID NO: 317, and SEQ ID NO: 318;oo) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 321, SEQ ID NO: 322, and SEQ ID NO: 323; and a light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID SEQ ID NO: 324, SEQ ID NO: 325, and SEQ ID NO: 326;pp) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 329, SEQ ID NO: 330, and SEQ ID NO: 331; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 332, SEQ ID NO: 333, and SEQ ID NO: 334;qq) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 337, SEQ ID NO: 338, and SEQ ID NO: 339; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 340, SEQ ID NO: 341, and SEQ ID NO: 342;rr) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 9, SEQ ID NO: 374, and SEQ ID NO: 375; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 376, SEQ ID NO: 13, and SEQ ID NO: 14; orss) a heavy chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 41, SEQ ID NO: 42, and SEQ ID NO: 43; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences selected from SEQ ID NO: 377, SEQ ID NO: 45, and SEQ ID NO: 46.
  • 5. The antibody or antigen-binding fragment thereof of claim 4, comprising a heavy chain variable region selected from the group consisting of: SEQ ID NO: 7, SEQ ID NO: 15, SEQ ID NO: 23, SEQ ID NO: 31, SEQ ID NO: 39, SEQ ID NO: 47, SEQ ID NO: 55, SEQ ID NO: 63, SEQ ID NO: 71, SEQ ID NO: 79, SEQ ID NO: 87, SEQ ID NO: 95, SEQ ID NO: 103, SEQ ID NO: 111, SEQ ID NO: 119, SEQ ID NO: 127, SEQ ID NO: 135, SEQ ID NO: 143, SEQ ID NO: 151, SEQ ID NO: 159, SEQ ID NO: 167, SEQ ID NO: 175, SEQ ID NO: 183, SEQ ID NO: 191, SEQ ID NO: 199, SEQ ID NO: 207, SEQ ID NO: 215, SEQ ID NO: 223, SEQ ID NO: 231, SEQ ID NO: 239, SEQ ID NO: 247, SEQ ID NO: 255, SEQ ID NO: 263, SEQ ID NO: 271, SEQ ID NO: 279, SEQ ID NO: 287, SEQ ID NO: 295, SEQ ID NO: 303, SEQ ID NO: 311, SEQ ID NO: 319, SEQ ID NO: 327, SEQ ID NO: 335, SEQ ID NO: 343, SEQ ID NO: 347, and SEQ ID NO: 349 and the homologue sequences of at least 80% sequence identity thereof.
  • 6. The antibody or antigen-binding fragment thereof of claim 4, comprising a light chain variable region selected from the group consisting of: SEQ ID NO: 8, SEQ ID NO: 16, SEQ ID NO: 24, SEQ ID NO: 32, SEQ ID NO: 40, SEQ ID NO: 48, SEQ ID NO: 56, SEQ ID NO: 64, SEQ ID NO: 72, SEQ ID NO: 80, SEQ ID NO: 88, SEQ ID NO: 96, SEQ ID NO: 104, SEQ ID NO: 112, SEQ ID NO: 120, SEQ ID NO: 128, SEQ ID NO: 136, SEQ ID NO: 144, SEQ ID NO: 152, SEQ ID NO: 160, SEQ ID NO: 168, SEQ ID NO: 176, SEQ ID NO: 184, SEQ ID NO: 192, SEQ ID NO: 200, SEQ ID NO: 208, SEQ ID NO: 216, SEQ ID NO: 224, SEQ ID NO: 232, SEQ ID NO: 240, SEQ ID NO: 248, SEQ ID NO: 256, SEQ ID NO: 264, SEQ ID NO: 272, SEQ ID NO: 280, SEQ ID NO: 288, SEQ ID NO: 296, SEQ ID NO: 304, SEQ ID NO: 312, SEQ ID NO: 320, SEQ ID NO: 328, SEQ ID NO: 336, SEQ ID NO: 344, SEQ ID NO: 348, and SEQ ID NO: 350 and the homologue sequences of at least 80% sequence identity thereof.
  • 7. The antibody or antigen-binding fragment thereof of claim 4, comprising: a) a heavy chain variable region comprising SEQ ID NO: 7 and a light chain variable region comprising SEQ ID NO: 8;b) a heavy chain variable region comprising SEQ ID NO: 15 and a light chain variable region comprising SEQ ID NO: 16;c) a heavy chain variable region comprising SEQ ID NO: 23 and a light chain variable region comprising SEQ ID NO: 24;d) a heavy chain variable region comprising SEQ ID NO: 31 and a light chain variable region comprising SEQ ID NO: 32;e) a heavy chain variable region comprising SEQ ID NO: 39 and a light chain variable region comprising SEQ ID NO: 40;f) a heavy chain variable region comprising SEQ ID NO: 47 and a light chain variable region comprising SEQ ID NO: 48;g) a heavy chain variable region comprising SEQ ID NO: 55 and a light chain variable region comprising SEQ ID NO: 56;h) a heavy chain variable region comprising SEQ ID NO: 63 and a light chain variable region comprising SEQ ID NO: 64;i) a heavy chain variable region comprising SEQ ID NO: 71 and a light chain variable region comprising SEQ ID NO: 72;j) a heavy chain variable region comprising SEQ ID NO: 79 and a light chain variable region comprising SEQ ID NO: 80;k) a heavy chain variable region comprising SEQ ID NO: 87 and a light chain variable region comprising SEQ ID NO: 88;l) a heavy chain variable region comprising SEQ ID NO: 95 and a light chain variable region comprising SEQ ID NO: 96;m) a heavy chain variable region comprising SEQ ID NO: 103 and a light chain variable region comprising SEQ ID NO: 104;n) a heavy chain variable region comprising SEQ ID NO: 111 and a light chain variable region comprising SEQ ID NO: 112;o) a heavy chain variable region comprising SEQ ID NO: 119 and a light chain variable region comprising SEQ ID NO: 120;p) a heavy chain variable region comprising SEQ ID NO: 127 and a light chain variable region comprising SEQ ID NO: 128;q) a heavy chain variable region comprising SEQ ID NO: 135 and a light chain variable region comprising SEQ ID NO: 136;r) a heavy chain variable region comprising SEQ ID NO: 143 and a light chain variable region comprising SEQ ID NO: 144;s) a heavy chain variable region comprising SEQ ID NO: 151 and a light chain variable region comprising SEQ ID NO: 152;t) a heavy chain variable region comprising SEQ ID NO: 159 and a light chain variable region comprising SEQ ID NO: 160;u) a heavy chain variable region comprising SEQ ID NO: 167 and a light chain variable region comprising SEQ ID NO: 168;v) a heavy chain variable region comprising SEQ ID NO: 175 and a light chain variable region comprising SEQ ID NO: 176;w) a heavy chain variable region comprising SEQ ID NO: 183 and a light chain variable region comprising SEQ ID NO: 184;x) a heavy chain variable region comprising SEQ ID NO: 191 and a light chain variable region comprising SEQ ID NO: 192;y) a heavy chain variable region comprising SEQ ID NO: 199 and a light chain variable region comprising SEQ ID NO: 200;z) a heavy chain variable region comprising SEQ ID NO: 207 and a light chain variable region comprising SEQ ID NO: 208;aa) a heavy chain variable region comprising SEQ ID NO: 215 and a light chain variable region comprising SEQ ID NO: 216;bb) a heavy chain variable region comprising SEQ ID NO: 223 and a light chain variable region comprising SEQ ID NO: 224;cc) a heavy chain variable region comprising SEQ ID NO: 231 and a light chain variable region comprising SEQ ID NO: 232;dd) a heavy chain variable region comprising SEQ ID NO: 239 and a light chain variable region comprising SEQ ID NO: 240;ee) a heavy chain variable region comprising SEQ ID NO: 247 and a light chain variable region comprising SEQ ID NO: 248;ff) a heavy chain variable region comprising SEQ ID NO: 255 and a light chain variable region comprising SEQ ID NO: 256;gg) a heavy chain variable region comprising SEQ ID NO: 263 and a light chain variable region comprising SEQ ID NO: 264;hh) a heavy chain variable region comprising SEQ ID NO: 271 and a light chain variable region comprising SEQ ID NO: 272;ii) a heavy chain variable region comprising SEQ ID NO: 279 and a light chain variable region comprising SEQ ID NO: 280;jj) a heavy chain variable region comprising SEQ ID NO: 287 and a light chain variable region comprising SEQ ID NO: 288;kk) a heavy chain variable region comprising SEQ ID NO: 295 and a light chain variable region comprising SEQ ID NO: 296;ll) a heavy chain variable region comprising SEQ ID NO: 303 and a light chain variable region comprising SEQ ID NO: 304;mm) a heavy chain variable region comprising SEQ ID NO: 311 and a light chain variable region comprising SEQ ID NO: 312;nn) a heavy chain variable region comprising SEQ ID NO: 319 and a light chain variable region comprising SEQ ID NO: 320;oo) a heavy chain variable region comprising SEQ ID NO: 327 and a light chain variable region comprising SEQ ID NO: 328;pp) a heavy chain variable region comprising SEQ ID NO: 335 and a light chain variable region comprising SEQ ID NO:336;qq) a heavy chain variable region comprising SEQ ID NO: 343 and a light chain variable region comprising SEQ ID NO: 344;rr) a heavy chain variable region comprising SEQ ID NO: 347 and a light chain variable region comprising SEQ ID NO: 348; orss) a heavy chain variable region comprising SEQ ID NO: 349 and a light chain variable region comprising SEQ ID NO: 350.
  • 8. (canceled)
  • 9. An antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising SEQ ID NO: 378 (EVOLVESGGGLXQPGXSLRLSCXTSGFTLSDYYMSWVRQXPGKGLEWVXF MRNKANXYTTEYSASVRGRFTISRDTSKSXIYLQMNSLXXEDTAVYYCVRDR XGRPFAYWGQGTLVTVSS), wherein the X at position i (i=12, 16, 23, 40, 49, 57, 80, 89, 90 and 103) of SEQ ID NO: 378 is referred as XHi, wherein XH12 is V or I, XH16 is G or R, XH23 is A or T, XH40 is A or P, XH49 is G or S, XH57 is A or G, XH80 is I or T, XH89 is R or K, XH90 is A or T, XH103 is D or E; and a light chain variable region comprising SEQ ID NO: 379 (DIXMTQSPXSLXXXXGXXXXIXCKSSQSLLNXINQKNFLTWYXQKPGXXPX LLIYWASTRESGVPXRFSGSGSGTDFTLXISXXXXEDLXXYYCQNDYTYPLTF GQGTKLEIK), wherein the X at position i (i=3, 9, 12, 13, 14, 15, 17, 18, 19, 20, 22, 32, 43, 48, 49, 51, 66, 80, 83, 84, 85, 86, 90 and 91) of SEQ ID NO: 379 is referred as XLi, wherein XL3 is V or Q, XL9 is D, L or S, XL12 is A, S or P, XL13 is A or V, XL14 is S or T, XL15 is L, V or P, XL17 is D or E, XL18 is R or P, XL19 is A or V, XL20 is S or T, XL22 is N, T or S, XL32 is A or S, XL43 is Q or L, XL48 is Q or K, XL49 is A, P or S, XL51 is K or Q, XL66 is S or D, XL80 is K or T, XL83 is R or S, XL84 is L or V, XL85 is Q or E, XL86 is A or P, XL90 is A or G, XL91 is T or V.
  • 10. An antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising SEQ ID NO: 380 (QVQLQESGPGLVKPSXTLSLTCXVXGYSITSDYAWNWIRQXPGKGLEWIGYI SHSGSTSYNPSLKSRVTISRDTSKNQFSLKLSSVTAADTAVYYCARSLGRRWY FDVWGQGTTVTVSS), wherein the X at position i (i=16, 23, 25 and 41) of SEQ ID NO: 380 is referred as XHi, wherein XH16 is E or Q, XH23 is A or T, XH25 is S or Y, XH41 is H or P; and a light chain variable region comprising SEQ ID NO: 381 (DIXMTQSPXSLXXXXGXXXXIXCKSSQSLLXSSTQKNYLAWYXQKPGXXPX LLIYFASTRDSGVPXRFSGSGSGTDFTLXISXXXXEDLXXYFCQQHYIIPFTFG QGTKLEIK), wherein the X at position i (i=3, 9, 12, 13, 14, 15, 17, 18, 19, 20, 22, 31, 43, 48, 49, 51, 66, 80, 83, 84, 85, 86, 90 and 91) of SEQ ID NO: 381 is referred as XLi, wherein XL3 is V or Q, XL9 is D, L or S, XL12 is A, S or P, XL13 is A or V, XL14 is S or T, XL15 is L, V or P, XL17 is D or E, XL18 is R or P, XL19 is A or V, XL20 is S or T, XL22 is N, T or S, XL31 is N or Q, XL43 is Q or L, XL48 is Q or K, XL49 is A, P or S, XL51 is K or Q, XL66 is S or D, XL80 is K or T, XL83 is R or S, XL84 is L or V, XL85 is Q or E, XL86 is A or P, XL90 is A or G, XL91 is T or V.
  • 11. The antibody or antigen-binding fragment thereof of claim 9, which comprises: a heavy chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 9, SEQ ID NO: 10 or 374 (MRNKANAYTT), and SEQ ID NO: 11 or 375 (VRDREGRPFAY), respectively; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 12 or 376 (QSLLNAINQKNF), SEQ ID NO: 13, and SEQ ID NO: 14, respectively.
  • 12. The antibody or antigen-binding fragment thereof of claim 9, which comprises a heavy chain variable region comprising a sequence selected from SEQ ID NO: 351, 353, 355, 357, 358, 360, 362 and 364; and a light chain variable region comprising a sequence selected from SEQ ID NO: 352, 354, 356, 359, 361 and 363.
  • 13-14. (canceled)
  • 15. The antibody or antigen-binding fragment thereof of claim 4, further comprising an immunoglobulin constant region, optionally a constant region of human Ig, or optionally a constant region of human IgG.
  • 16-17. (canceled)
  • 18. The antibody or antigen-binding fragment thereof of claim 4, which is a Fab, a Fab′, a F(ab′), a Fd, an Fv fragment, a disulfide stabilized Fv fragment (dsFv), a (dsFv)2, a single-chain antibody molecule (scFv), a camelized single domain antibody, a nanobody, a domain antibody, and a bivalent domain antibody.
  • 19. The antibody or antigen-binding fragment thereof of claim 4, wherein the antibody or antigen-binding fragment is linked to one or more conjugates, optionally, wherein the conjugate is covalently attached either directly or via a linker.
  • 20-22. (canceled)
  • 23. A pharmaceutical composition comprising the antibody or antigen-binding fragment thereof of claim 4, and a pharmaceutically acceptable carrier.
  • 24-25. (canceled)
  • 26. An isolated polynucleotide encoding the antibody or antigen-binding fragment thereof of claim 4.
  • 27. A vector comprising the isolated polynucleotide of claim 26.
  • 28. A host cell comprising the vector of claim 27.
  • 29. (canceled)
  • 30. A method of treating a disease or condition in a subject that would benefit from modulation of CD276 activity, comprising administering to the subject a therapeutically effective amount of the antibody or antigen-binding fragment thereof of claim 4.
  • 31. (canceled)
  • 32. The method of claim 30, wherein the disease or condition is cancer, adaptive immune disease, autoimmune disease, inflammatory disease, or infectious disease.
  • 33-40. (canceled)
  • 41. A method of modulating CD276 activity in a CD276-expressing cell, comprising exposing the CD276-expressing cell to the antibody or antigen-binding fragment thereof of claim 4.
  • 42-67. (canceled)
  • 68. The antibody or antigen-binding fragment thereof of claim 10, which comprises: a heavy chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 41, SEQ ID NO: 42, and SEQ ID NO: 43, respectively; and a kappa light chain variable region comprising 1, 2, or 3 CDR sequences shown as SEQ ID NO: 44 or 377 (QSLLOSSTOKNY), SEQ ID NO: 45, and SEQ ID NO: 46, respectively.
  • 69. The antibody or antigen-binding fragment thereof of claim 10, which comprises a heavy chain variable region comprising a sequence selected from SEO ID NO: 365, 367 and 370; and a light chain variable region comprising a sequence selected from SEO ID NO: 366, 368, 369, 371, 372 and 373.
Priority Claims (2)
Number Date Country Kind
PCT/CN2021/093157 May 2021 WO international
PCT/CN2022/089645 Apr 2022 WO international
PCT Information
Filing Document Filing Date Country Kind
PCT/CN2022/092138 5/11/2022 WO