Patent Application
20240299507
The instant application contains a Sequence Listing which has been submitted electronically in XML format and is hereby incorporated by reference in its entirety. Said XML copy, created on Mar. 21, 2024, is named 56699-737.301_Replacement SL.xml and is 1,390,328 bytes in size.
The present application relates to humanized and non-human anti-MUC1* antibodies and methods of making and using them. The present application also relates to using an immune cell transfected or transduced with a cleavage enzyme for the treatment of cancer. The present invention also relates to using an immune cells transfected or transduced with a CAR and another protein for the treatment of cancer.
We previously discovered that a cleaved form of the MUC1 (SEQ ID NO:1) transmembrane protein is a growth factor receptor that drives the growth of over 75% of all human cancers. The cleaved form of MUC1, which we called MUC1* (pronounced muk 1 star), is a powerful growth factor receptor. Cleavage and release of the bulk of the extracellular domain of MUC1 unmasks a binding site for activating ligands dimeric NME1, NME6, NME7, NME7AB, NME7-X1 or NME8. It is an ideal target for cancer drugs as it is aberrantly expressed on over 75% of all cancers and is likely overexpressed on an even higher percentage of metastatic cancers (Mahanta et al. (2008) A Minimal Fragment of MUC1 Mediates Growth of Cancer Cells. PLOS ONE 3(4): e2054. doi:10.1371/journal.pone.0002054; Fessler et al. (2009), “MUC1* is a determinant of trastuzumab (Herceptin) resistance in breast cancer cells,” Breast Cancer Res Treat. 118(1): 113-124). After MUC1 cleavage most of its extracellular domain is shed from the cell surface. The remaining portion has a truncated extracellular domain that comprises most or all of the primary growth factor receptor sequence called PSMGFR (SEQ ID NO:2).
Antibodies are increasingly used to treat human diseases. Antibodies generated in non-human species have historically been used as therapeutics in humans, such as horse antibodies. More recently, antibodies are engineered or selected so that they contain mostly human sequences in order to avoid a generalized rejection of the foreign antibody. The process of engineering recognition fragments of a non-human antibody into a human antibody is generally called ‘humanizing’. The amount of non-human sequences that are used to replace the human antibody sequences determines whether they are called chimeric, humanized or fully human.
Alternative technologies exist that enable generation of humanized or fully human antibodies. These strategies involve screening libraries of human antibodies or antibody fragments and identifying those that bind to the target antigen, rather than immunizing an animal with the antigen. Another approach is to engineer the variable region(s) of an antibody into an antibody-like molecule. Another approach involves immunizing a humanized animal. The present invention is intended to also encompass these approaches for use with recognition fragments of antibodies that the inventors have determined bind to the extracellular domain of MUC1*.
In addition to treating patients with an antibody, cancer immunotherapies have recently been shown to be effective in the treatment of blood cancers. One cancer immunotherapy, called CAR T (chimeric antigen receptor T cell) therapy, engineers a T cell so that it expresses a chimeric receptor having an extra cellular domain that recognizes a tumor antigen, and a transmembrane and cytoplasmic tail of a T cell (Dai H, Wang Y, Lu X, Han W. (2016) Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy. J Natl Cancer Inst. 108(7): djv439). Such receptor is composed of an single chain antibody fragment (scFv) that recognizes a tumor antigen, linked to a T cell transmembrane and signaling domains. Upon binding of the receptor to a cancer associated antigen, a signal is transmitted resulting in T-cell activation, propagation and the targeted killing of the cancer cells. In practice, a patient's T cells are isolated and transduced with a CAR, expanded and then injected back into the patient. When the patient's CAR T cells bind to the antigen on a cancer cell, the CAR T cells expand and attack the cancer cells. A drawback of this method is the risk of activating the patient's immune system to destroy cells bearing the target antigen, when most cancer antigens are expressed on some healthy tissues, but overexpressed on cancerous tissues. To minimize the risk of off-tumor/on-target effects, the cancer antigen should be minimally expressed on healthy tissues.
Another cancer immunotherapy involves BiTEs (Bi-specific T cell Engagers). The BiTE approach attempts to eliminate the CAR T associated risk of off-tumor/on-target effects. Unlike CAR T, BiTEs are bispecific antibodies that should not pose any greater risk than regular antibody-based therapies. However, unlike typical anti-cancer antibodies that bind to and block a cancer antigen, BiTEs are designed to bind to an antigen on the tumor cell and simultaneously bind to an antigen on an immune cell, such as a T cell. In this way, a BiTE recruits the T cell to the tumor. BiTEs are engineered proteins that simultaneously bind to a cancer associated antigen and a T-cell surface protein such as CD3-epsilon. BiTEs are antibodies made by genetically linking the scFv's of an antibody that binds to a T cell antigen, like anti-CD3-epsilon to a scFv of a therapeutic monoclonal antibody that binds to a cancer antigen (Patrick A. Baeuerle, and Carsten Reinhardt (2009) Bispecific T-cell engaging antibodies for cancer therapy. Cancer Res. 69(12):4941-4944).
In one aspect, the present invention is directed to a non-human, human or humanized anti-MUC1* antibody or antibody fragment or antibody-like protein that binds to a region on extracellular domain of MUC1 isoform or cleavage product that is devoid of the tandem repeat domains. The non-human, human or humanized anti-MUC1* antibody or antibody fragment or antibody-like protein may specifically bind to
The non-human, human or humanized antibody may be IgG1, IgG2, IgG3, IgG4 or IgM. The human or humanized antibody fragment or antibody-like protein may be scFv or scFv-Fc.
The human or humanized antibody, antibody fragment or antibody-like protein as in above may comprise a heavy chain variable region and light chain variable region which is derived from mouse monoclonal MN-E6 antibody, and has at least 80%, 90% or 95% or 98% sequence identity to the mouse monoclonal MN-E6 antibody. The heavy chain variable region may have at least 90% or 95% or 98% sequence identity to SEQ ID NO:13 and the light chain variable region may have at least 90% or 95% or 98% sequence identity to SEQ ID NO:66.
The human or humanized antibody, antibody fragment or antibody-like protein according to above may include complementarity determining regions (CDRs) in the heavy chain variable region and light chain variable region having at least 90% or 95% or 98% sequence identity to CDR1, CDR2 or CDR3 regions having sequence as follows:
The human or humanized antibody, antibody fragment or antibody-like protein described above may include a heavy chain variable region and light chain variable region which is derived from mouse monoclonal MN-C2 antibody, and has at least 80%, 90% or 95% or 98% sequence identity to the mouse monoclonal MN-C2 antibody. The heavy chain variable region may have at least 90% or 95% or 98% sequence identity to SEQ ID NO:119 and the light chain variable region has at least 90% or 95% or 98% sequence identity to SEQ ID NO:169. The complementarity determining regions (CDRs) in the heavy chain variable region and light chain variable region may have at least 90% or 95% or 98% sequence identity to CDR1, CDR2 or CDR3 regions having sequence as follows:
The human or humanized antibody, antibody fragment or antibody-like protein as in above may include a heavy chain variable region and light chain variable region which is derived from mouse monoclonal MN-C3 antibody, and may have at least 80%, 90% or 95% or 98% sequence identity to the mouse monoclonal MN-C3 antibody. The heavy chain variable region may have at least 90% or 95% or 98% sequence identity to SEQ ID NO:414 and the light chain variable region may have at least 90% or 95% or 98% sequence identity to SEQ ID NO:459. The complementarity determining regions (CDRs) in the heavy chain variable region and light chain variable region may have at least 90% or 95% or 98% sequence identity to CDR1, CDR2 or CDR3 regions having sequence as follows:
The human or humanized antibody, antibody fragment or antibody-like protein described above may include a heavy chain variable region and light chain variable region which is derived from mouse monoclonal MN-C8 antibody, and has at least 80%, 90% or 95% or 98% sequence identity to the mouse monoclonal MN-C8 antibody. The heavy chain variable region may have at least 90% or 95% or 98% sequence identity to SEQ ID NO:506 and the light chain variable region may have at least 90% or 95% or 98% sequence identity to SEQ ID NO:544. The complementarity determining regions (CDRs) in the heavy chain variable region and light chain variable region may have at least 90% or 95% or 98% sequence identity to CDR1, CDR2 or CDR3 regions having sequence as follows:
In another aspect, the present invention is directed to an anti-MUC1* extracellular domain antibody comprised of sequences of a humanized MN-E6 represented by humanized IgG2 heavy chain, or humanized IgG1 heavy chain, paired with humanized Kappa light chain, or humanized Lambda light chain. The humanized IgG2 heavy chain may be SEQ ID NOS:53, humanized IgG1 heavy chain may be SEQ ID NO:57, humanized Kappa light chain may be SEQ ID NO:108, and humanized Lambda light chain may be SEQ ID NO:112, or a sequence having 90%, 95% or 98% sequence identity thereof.
In another aspect, the invention is directed to an anti-MUC1* extracellular domain antibody comprised of sequences of a humanized MN-C2 represented by humanized IgG1 heavy chain, humanized IgG2 heavy chain, paired with humanized Lambda light chain, and humanized Kappa light chain. The humanized IgG1 heavy chain MN-C2 may be SEQ ID NOS:159 or IgG2 heavy chain may be SEQ ID NOS:164 paired with Lambda light chain (SEQ ID NO:219) or Kappa light chain (SEQ ID NO:213), or a sequence having 90%, 95% or 98% sequence identity thereof.
In another aspect, the invention is directed to an anti-MUC1* extracellular domain antibody comprised of sequences of a humanized MN-C3 represented by humanized IgG1 heavy chain or humanized IgG2 heavy chain paired with humanized Lambda light chain or humanized Kappa light chain. The humanized MN-C3 IgG1 heavy chain may be SEQ ID NOS:454, IgG2 heavy chain may be SEQ ID NOS:456, Lambda light chain may be SEQ ID NO:501, and Kappa light chain may be SEQ ID NO:503, or a sequence having 90%, 95% or 98% sequence identity thereof.
In another aspect, the invention is directed to an anti-MUC1* extracellular domain antibody comprised of sequences of a humanized MN-C8 represented by humanized IgG1 heavy chain or humanized IgG2 heavy chain paired with humanized Lambda light chain or humanized Kappa light chain. The humanized MN-C8 IgG1 heavy chain may be SEQ ID NOS:540, IgG2 heavy chain may be SEQ ID NOS:542, Lambda light chain may be SEQ ID NO:580 and Kappa light chain may be SEQ ID NO:582, or a sequence having 90%, 95% or 98% sequence identity thereof.
In another aspect, the invention is directed to a human or humanized anti-MUC1* antibody or antibody fragment or antibody-like protein according to above, which inhibits the binding of NME protein to MUC1*. The NME may be NME1, NME6, NME7AB, NME7-X1, NME7 or NME8.
In yet another aspect, the invention is directed to a single chain variable fragment (scFv) comprising a heavy and light chain variable regions connected via a linker, further comprising CDRs of antibodies that bind to MUC1* extracellular domain. The CDRs may be derived from MN-E6, MN-C2, MN-C3 or MN-C8 antibodies or humanized antibodies thereof. The scFv may be one that possesses the SEQ ID NOS:233, 235 and 237 (E6); SEQ ID NOS:239, 241, and 243 (C2); SEQ ID NOS:245, 247, and 249 (C3); or SEQ ID NOS:251, 253, and 255 (C8).
In still another aspect, the invention is directed to a chimeric antigen receptor (CAR) comprising a scFv or a humanized variable region that binds to the extracellular domain of a MUC1 that is devoid of tandem repeats, a linker molecule, a transmembrane domain and a cytoplasmic domain. The single chain antibody fragment may bind to
In the CAR as described above, portions of any of the variable regions set forth and described above, or combination thereof may be used in the extracellular domain of the CAR. The CAR also comprises a transmembrane region and a cytoplasmic tail that comprises sequence motifs that signal immune system activation. The extracellular domain may be comprised of non-human, or humanized single chain antibody fragments of an MN-E6 scFv, MN-C2 scFv, MN-C3 scFv or MN-C8 scFv.
In the CAR as described above, the extracellular domain may include a non-human or humanized single chain antibody fragments of an MN-E6 scFv set forth as SEQ ID NOS: 233, 235, or 237), MN-C2 scFv (SEQ ID NOS:239, 241, or 243), MN-C3 scFv (SEQ ID NOS: 245, 247, or 249) or MN-C8 scFv (SEQ ID NOS:251, 253, or 255).
In any of the CARs described above, the cytoplasmic tail may be comprised of one or more of signaling sequence motifs CD3-zeta, CD27, CD28, 4-1BB, OX40, CD30, CD40, ICAm-1, LFA-1, ICOS, CD2, CD5, or CD7.
In any of the CARs described above, the sequence may be CARMN-E6 CD3z (SEQ ID NOS:295), CARMN-E6 CD28/CD3z (SEQ ID NOS:298); CARMN-E6 4-1BB/CD3z (SEQ ID NOS:301); CARMN-E6 OX40/CD3z (SEQ ID NOS:617); CARMN-E6 CD28/4-1BB/CD3z (SEQ ID NOS:304); CARMN-E6 CD28/OX40/CD3z (SEQ ID NOS:619); CAR MN-C2 CD3z (SEQ ID NOS:607); CAR MN-C2 CD28/CD3z (SEQ ID NOS:609); CAR MN-C2 4-1BB/CD3z (SEQ ID NOS:611 and SEQ ID NOS: 719); CAR MN-C2 OX40/CD3z (SEQ ID NOS:613); CAR MN-C2 CD28/4-1BB/CD3z (SEQ ID NOS: 307); CAR MN-C2 CD28/OX40/CD3z (SEQ ID NOS:615) or CAR MN-C3 4-1BB/CD3z (SEQ ID NOS: 601).
In another aspect, the CAR may have an extracellular domain unit that recognizes a peptide. The peptide may be PSMGFR (SEQ ID NO:2). The peptide may be a peptide derived from NME7. The peptide may be
In another aspect, the invention is directed to a composition that includes at least two CARs with different extracellular domain units transfected into the same cell, which may be an immune cell, which may be derived from the patient requiring treatment for a cancer. The expression of the second CAR may be inducible and driven by the recognition of a target by the first CAR. The nucleic acid encoding the second CAR may be linked to an inducible promoter. The expression of the second CAR may be induced by an event that occurs specifically when the immune cell mounts an immune response to a target tumor cell. The antibody fragments of one or both of the CARs may direct the cell to a MUC1* positive tumor. The antibody fragments of the first and second CARs may bind to a MUC1* that is produced when MUC1 is cleaved by two different cleavage enzymes. Expression of the second CAR by the inducible promoter may be induced when the antibody fragment of the first CAR engages or binds to a MUC1 or MUC1* on the tumor. One way to do this is to induce expression of the second CAR when, or shortly after, an NFAT protein is expressed or translocated to the nucleus. For example, a sequence derived from an NFAT promoter region is put upstream of the gene for the second CAR. In this way, when the transcription factors that bind to the promoter of the NFAT protein are present in sufficient concentration to bind to and induce transcription of the NFAT protein, they will also bind to that same promoter that is engineered in front of the sequence for transcription of the second CAR. The NFAT protein may be NFAT1 also known as NFATc2, NFAT2 also known as NFATc or NFATc1, NFAT3 also known as NFATc4, NFAT4 also known as NFATc3, or NFAT5. In one aspect of the invention, the NFAT is NFATc1, NFATc3 or NFATc2. In one aspect of the invention, the NFAT is NFAT2 also known as NFATc1. SEQ ID NO:646 shows nucleic acid sequence of the upstream transcriptional regulatory region for NFAT2. The recognition unit of the second CAR may be an antibody fragment or a peptide, wherein the recognition units may bind to NME7, PD-1, PDL-1, or a checkpoint inhibitor.
The at least two CARs may have one CAR that does not have a tumor antigen targeting recognition unit and the other CAR does have a tumor antigen targeting recognition unit. In another aspect of the invention, one of the extracellular domain recognition units may bind to MUC1* extracellular domain. In another aspect of the invention, one of the extracellular domain recognition units may be an antibody fragment and the other is a peptide, which may be devoid of transmembrane and signaling motifs; the peptide may be a single chain antibody fragment. In another aspect of the invention, one of the recognition units may bind PD-1 or PDL-1. In another aspect of the invention, one extra cellular domain recognition unit is an anti-MUC1* scFv chosen from the group consisting of scFv of MN-E6 antibody, scFv of MN-C2 antibody, scFv of MN-C3 antibody or scFv of MN-C8 antibody and the other is a peptide derived from NME7 or chosen from the group consisting of
In another aspect, the invention is directed to a cell comprising a CAR with an extracellular domain that binds to the extra cellular domain of a MUC1 molecule that is devoid of tandem repeats. In another aspect, the invention is directed to a cell comprising a CAR with an extracellular domain that binds to a MUC1* transfected or transduced cell. The cell that includes the CAR may be an immune system cell, preferably a T cell, a natural killer cell (NK), a dendritic cell or mast cell.
In another aspect, the invention is directed to an engineered antibody-like protein.
In another aspect, the invention is directed to a method of screening a library of antibodies or antibody fragments that are human, for those that bind to
In another aspect, the invention is directed to a method for treating a disease in a subject comprising administering an antibody according to any claim above, to a person suffering from the disease, wherein the subject expresses MUC1 aberrantly. The disease may be cancer, such as breast cancer, ovarian cancer, lung cancer, colon cancer, gastric cancer or esophageal cancer.
In another aspect, the invention is directed to a method for treating a disease in a subject comprising administering an NME peptide, to a person suffering from the disease, wherein the subject expresses MUC1 aberrantly.
In another aspect, the invention is directed to a method of proliferating or expanding stem cell population comprising contacting the cells with the antibody according to any method or composition described above.
In another aspect, the invention is directed to a method of facilitating stem cell attachment to a surface comprising coating the surface with a humanized MN-C3 or MN-C8 antibody, antibody fragment or single chain antibody thereof and contacting stem cell to the surface.
In another aspect, the invention is directed to a method of delivering stem cell in vitro or in vivo comprising the steps of coating a surface with a humanized MN-C3 or MN-C8 antibody, antibody fragment or single chain antibody thereof, contacting the stem cell to the surface and delivering the stem cell to a specific location.
In another aspect, the invention is directed to a method of isolating stem cell comprising the steps of coating a surface with a humanized MN-C3 or MN-C8 antibody, antibody fragment or single chain antibody thereof, and contacting a mixed population of cells to the surface and isolating stem cell.
In another aspect, the invention is directed to a scFv comprising variable domain fragments derived from an antibody that binds to an extracellular domain of MUC1 isoform or cleavage product that is devoid of the tandem repeat domains. The variable domain fragments may be derived from mouse monoclonal antibody MN-E6 (SEQ ID NO:13 and 66) or from the humanized MN-E6 (SEQ ID NO: 39 and 94), or from MN-E6 scFv (SEQ ID NO: 233, 235 and 237). Or, the variable domain fragments may be derived from mouse monoclonal antibody MN-C2 (SEQ ID NO: 119 and 169) or from the humanized MN-C2 (SEQ ID NO: 145 and 195), or from MN-C2 scFv (SEQ ID NO: 239, 241 and 243). Or, the variable domain fragments may be derived from mouse monoclonal antibody MN-C3 (SEQ ID NO: 414 and 459) or from the humanized MN-C3 (SEQ ID NO: 440 and 487), or from MN-C3 scFv (SEQ ID NO: 245, 247 and 249). Or, the variable domain fragments may be derived from mouse monoclonal antibody MN-C8 (SEQ ID NO: 505 and 544) or from the humanized MN-C8 (SEQ ID NO: 526 and 566), or from MN-C8 scFv (SEQ ID NO: 251, 253, 255).
In another aspect, the invention is directed to a method for the treatment of a person diagnosed with, suspected of having or at risk of developing a MUC1 or MUC1* positive cancer involving administering to the person an effective amount of the scFv described above.
In another aspect, the invention is directed to a scFv-Fc construct comprising the scFv as described above. The scFv-Fc may be dimerized. The Fc component may be mutated so that scFv-Fc is monomeric. The mutation may include mutating or deleting hinge region on Fc, making F405Q, Y407R, T366W/L368W, or T364R/L368R mutation or combinations thereof on the Fc represented by SEQ ID NO: 281, 279, 285 and 287.
In another aspect, the invention is directed to a polypeptide comprising at least two different scFv sequences, wherein one of the scFv sequences is a sequence that binds to extracellular domain of MUC1 isoform or cleavage product that is devoid of the tandem repeat domains. The polypeptide may bind to
The polypeptide may bind to a receptor on an immune cell, such as T cell, and in particular, CD3 on T-cell.
In another aspect, the invention is directed to a method of detecting presence of a cell that expresses MUC1* aberrantly, comprising contacting a sample of cells with the scFv-Fc described above and detecting for the presence of the binding of scFv-Fc to the cell. The cell may be cancer cell.
In another aspect, the invention is directed to a method for testing a subject's cancer for suitability of treatment with a composition comprising portions of the variable regions of MN-E6, MN-C2, MN-C3 or MN-C8, comprising the steps of contacting a bodily specimen from the patient with the corresponding MN-E6 scFv-Fc, MN-C2 scFv-Fc, MN-C3 scFv-Fc or MN-C8 scFv-Fc.
In another aspect, the invention is directed to a method of treating a subject suffering from a disease comprising, exposing T cells from the subject to MUC1* peptides wherein through various rounds of maturation, T cells develop MUC1* specific receptors, creating adapted T cells, and expanding and administering the adapted T cells to the donor patient who is diagnosed with, suspected of having, or is at risk of developing a MUC1* positive cancer.
In one aspect, the invention may be directed to an immune cell transfected or transduced with a cleavage enzyme for the treatment of cancer. The cancer may be a MUC1 positive cancer. The immune cell may be a T cell. The immune cell may be derived from the patient to be treated. The cleavage enzyme may be an MMP or ADAM family member. The cleavage enzyme may be MMP2, MMP9, MMP3, MMP14, ADAM17, ADAM28, or ADAM TS16.
In another aspect of the invention, the cleavage enzyme is administered directly to the patient, alone or concurrent with an agent for the treatment of cancer, including but not limited to chemotherapy agents, targeted biologicals, CAR T cells, BiTEs or ADCs. In one aspect, the cleavage enzyme is MMP1, MMP2, MMP3, MMP7, MMP8, MMP9, MMP11, MMP12, MMP13, MMP14, MMP16, ADAM9, ADAM10, ADAM17, ADAM 19, ADAMTS16, ADAM28 or a catalytically active fragment thereof. In another aspect, the cleavage enzyme is MMP9 or MMP14 and the other agent for the treatment of cancer is an anti-MUC1* CAR T cell. In yet another aspect, the cleavage enzyme is MMP9 or MMP14 and the other agent for the treatment of cancer is an anti-MUC16 CAR T cell.
In another aspect, the invention may be directed to an immune cell transfected or transduced with a CAR wherein its extra cellular domain comprises an antibody scFv that binds to the extra cellular domain of a MUC1 molecule that is devoid of the tandem repeats.
In another aspect, the invention may be directed to an immune cell transfected or transduced with a cleavage enzyme for the treatment of cancer. The cancer may be a MUC1 positive cancer. The immune cell may be a T cell. The immune cell may be an NK cell. The cleavage enzyme may be any enzyme that cleaves MUC1 such that the tandem repeat domain is separated from the transmembrane domain. Such cleavage enzymes include but are not limited to MMP1, MMP2, MMP3, MMP7, MMP8, MMP9, MMP11, MMP12, MMP13, MMP14, MMP16, ADAM9, ADAM10, ADAM17, ADAM 19, ADAMTS16, ADAM28 or a catalytically active fragment thereof. The immune cell may be further transfected or transduced with an activator of the cleavage enzyme. The cleavage enzyme may be without limitation, MMP2 or MMP9 or ADAM17, and the activator of cleavage enzymes MMP2 and MMP9 may be MMP14 and MMP3, respectively. The nucleic acid encoding the cleavage enzyme may be linked to an inducible promoter. The expression of the cleavage enzyme may be induced by an event that occurs specifically when the immune cell mounts an immune response to a target tumor cell. In one aspect of the invention, the cleavage enzyme cleaves MUC1 such that the cleavage product is recognized by an antibody that specifically recognizes cleaved MUC1 on cancerous tissues. In one aspect, the antibody that specifically recognizes cleaved MUC1 on cancerous tissues would bind to cancerous tissues at least two-times more than it binds to healthy tissues where T cells normally traffic.
In another aspect, the invention may be directed to an immune cell transfected or transduced with a CAR comprising an antibody fragment, and a cleavage enzyme for the treatment of cancer. The cancer may be a MUC1 positive cancer. The immune cell may be a T cell. The antibody fragment of the CAR on the T cell may direct the cell to a MUC1* positive tumor. The antibody fragment of the CAR on the T cell may recognize a form of MUC1 after it is cleaved by that specific cleavage enzyme. The antibody fragment of the CAR may be derived from MNC2 or MNE6 and the cleavage enzyme may be MMP9, MMP2, or ADAM17 or an activated form of MMP9, MMP2 or ADAM17. The immune cell may be further transfected or transduced with an activator of the cleavage enzyme. The cleavage enzyme maybe MMP2 or MMP9 or ADAM17, and an activator of cleavage enzymes MMP2 and MMP9 may be MMP14 and MMP3, respectively. The nucleic acid encoding the cleavage enzyme may be linked to an inducible promoter. The expression of the cleavage enzyme may be induced by an event that occurs specifically when the immune cell mounts an immune response to a target tumor cell. The antibody fragment may recognize a form of MUC1 or MUC1* that is created when the cleavage enzyme cleaves MUC1 or MUC1*. Expression of the cleavage enzyme by the inducible promoter may be induced when the antibody fragment of the CAR engages or binds to a MUC1 or MUC1* on the tumor.
In another aspect, the invention is directed to a method of treating cancer in a patient comprising administering to the patient the immune cell of any of the above, in combination with a checkpoint inhibitor.
It can also be appreciated that in any of the methods above, particularly in the methods of treating cancer, the MUC1 cleavage enzyme can be administered directly to the patient without necessarily being expressed from a nucleic acid construct.
In this regard, in one aspect, the present invention is directed to a method for treating a patient diagnosed with cancer comprising administering directly to the patient, a MUC1 cleavage enzyme, alone or concurrent with an agent for treating cancer. The agent may be a chemotherapy agent, targeted biological, CAR T cell, BiTE or antibody drug conjugate (ADC). The cleavage enzyme may be MMP1, MMP2, MMP3, MMP7, MMP8, MMP9, MMP11, MMP12, MMP13, MMP14, MMP16, ADAM9, ADAM10, ADAM17, ADAM 19, ADAMTS16, ADAM28 or a catalytically active fragment thereof. The agent may be an anti-MUC1* CAR T cell. In the CAR, the single chain antibody fragment may bind to a peptide comprising at least 12 contiguous amino acids of
In the method above, any of the variable regions set forth in the following may be used:
In the method above, in the CAR, the extracellular domain may be comprised of humanized single chain antibody fragments of an MN-E6 scFv, MN-C2 scFv, MN-C3 scFv or MN-C8 scFv. The extracellular domain may be comprised of humanized single chain antibody fragments of an MN-E6 scFv set forth as SEQ ID NOS: 233, 235, or 237), MN-C2 scFv (SEQ ID NOS:239, 241, or 243), MN-C3 scFv (SEQ ID NOS: 245, 247, or 249) or MN-C8 scFv (SEQ ID NOS:251, 253, or 255). In the CAR, the cytoplasmic tail may be comprised of one or more of signaling sequence motifs CD3-zeta, CD27, CD28, 4-1BB, OX40, CD30, CD40, ICAm-1, LFA-1, ICOS, CD2, CD5, or CD7.
In the CAR above, its sequence may be CARMN-E6 CD3z (SEQ ID NOS:295), CARMN-E6 CD28/CD3z (SEQ ID NOS:298); CARMN-E6 4-1BB/CD3z (SEQ ID NOS:301); CARMN-E6 OX40/CD3z (SEQ ID NOS:617); CARMN-E6 CD28/4-1BB/CD3z (SEQ ID NOS:304); CARMN-E6 CD28/OX40/CD3z (SEQ ID NOS:619); CAR-MN-E6 Fc/4-1BB/CD3z (SEQ ID NOS:311), CAR-MN-E6 IgD/Fc/4-1BB/CD3z (SEQ ID NOS:771), CAR-MN-E6 FcH/4-1BB/CD3z (SEQ ID NOS:316), CAR-MN-E6 IgD/FcH/4-1BB/CD3z (SEQ ID NOS:773), CAR-MN-E6 IgD/4-1BB/CD3z (SEQ ID NOS:324), CAR-MN-E6 X4/4-1BB/CD3z (SEQ ID NOS:331), CAR MN-C2 CD3z (SEQ ID NOS:607); CAR MN-C2 CD28/CD3z (SEQ ID NOS:609); CAR MN-C2 4-1BB/CD3z (SEQ ID NOS:611); CAR MN-C2 OX40/CD3z (SEQ ID NOS:613); CAR MN-C2 CD28/4-1BB/CD3z (SEQ ID NOS:307); CAR MN-C2 CD28/OX40/CD3z (SEQ ID NOS:615), CAR44 huMNC2-CD8-4-1BB-CD3z (SEQ ID NOS:719), CAR-MN-C2 Fc/4-1BB/CD3z (SEQ ID NOS:733), CAR-MN-C2 IgD/Fc/4-1BB/CD3z (SEQ ID NOS:735), CAR-MN-C2 FcH/4-1BB/CD3z (SEQ ID NOS:737), CAR-MN-C2 IgD/FcH/4-1BB/CD3z (SEQ ID NOS:739), CAR-MN-C2 IgD/4-1BB/CD3z (SEQ ID NOS:741), CAR-MN-C2 X4/4-1BB/CD3z (SEQ ID NOS:743).
The above method may comprise a cell comprising a CAR with an extracellular domain that binds to MUC1* transfected or transduced cell. The cell may including the CAR may be an immune system cell. The immune system cell may be T cell, NK cell, dendritic cell or mast cell.
In the method above, the agent may be an anti-MUC16 CAR T cell.
The method above may include at least two CARs with different extracellular domain units transfected into the same cell. One of the extracellular domain recognition units may bind to MUC1* extracellular domain. One of the extracellular domain recognition units may bind to PD-1. One of the extracellular domain recognition units may be an antibody fragment and the other may be a peptide or an anti-MUC1* antibody fragment.
The method may include an immune cell transfected or transduced with a plasmid encoding a CAR and a plasmid encoding a non-CAR species that is expressed from an inducible promoter. The non-CAR species may be expressed from an inducible promoter that is activated by elements of an activated immune cell. The non-CAR species may be expressed from an NFAT inducible promoter. The NFAT may be NFATc1, NFATc3 or NFATc2. The cleavage enzyme may be MMP2, MMP3, MMP9, MMP13, MMP14, MMP16, ADAM10, ADAM17, or ADAM28, or a catalytically active fragment thereof. The non-CAR species may be a cytokine. The cytokine may be IL-7, IL-12, IL-15 or IL-18.
These and other objects of the invention will be more fully understood from the following description of the invention, the referenced drawings attached hereto and the claims appended hereto.
The present invention will become more fully understood from the detailed description given herein below, and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein;
Table 1 shows details of many of the anti-MUC1* CARs that were generated and tested. For each construct shown, a number assigned to that CAR, promoter used, signal peptide, antibody species, sequences of scFv, hinge region, transmembrane domain, and signaling motifs used in each CAR, length of the insert in number of base pairs, its molecular weight and the length of the construct are displayed.
Table 2 shows cytokine release data for some of the CARs after transduction into human T cells and co-cultured with a variety of cancer cells.
In the present application, “a” and “an” are used to refer to both single and a plurality of objects.
As used herein, occasionally, in short hand, a polypeptide is indicated as being “transduced or transfected” into a cell. In these occurrences, it is understood that the nucleic acid encoding the polypeptide sequence is transduced or transfected into the cell, as it is an impossibility that a polypeptide could be transduced or transfected into a cell.
As used herein, occasionally when referring to number of cells injected into an animal or otherwise contextually wherein the number of cells is referred to, “M” refers to millions, and “K” refers to thousands.
As used herein, interchangeable designations for various monoclonal antibodies are used, such as, “MN-C2”, which is interchangeable with “C2”, “Min-C2” and “MNC2”; “MN-E6”, which is interchangeable with “E6”, “Min-E6” and “MNE6”; “MN-C3”, which is interchangeable with “C3”, “Min-C3” and “MNC3”; and “MN-C8”, which is interchangeable with “C8”, “Min-C8” and “MNC8”.
As used herein, “h” or “hu” placed before an antibody construct is short-hand for humanized.
As used herein, the term “antibody-like” means a molecule that may be engineered such that it contains portions of antibodies but is not an antibody that would naturally occur in nature. Examples include but are not limited to CAR (chimeric antigen receptor) T cell technology and the Ylanthia® technology. The CAR technology uses an antibody epitope fused to a portion of a T cell so that the body's immune system is directed to attack a specific target protein or cell. The Ylanthia® technology consists of an “antibody-like” library that is a collection of synthetic human Fabs that are then screened for binding to peptide epitopes from target proteins. The selected Fab regions can then be engineered into a scaffold or framework so that they resemble antibodies.
As used herein, “PSMGFR” is abbreviation for Primary Sequence of the MUC1 Growth Factor Receptor which is identified by SEQ ID NO:2, and thus is not to be confused with a six amino acid sequence. “PSMGFR peptide” or “PSMGFR region” refers to a peptide or region that incorporates the Primary Sequence of the MUC1 Growth Factor Receptor (SEQ ID NO:2).
As used herein, the “MUC1*” extra cellular domain is defined primarily by the PSMGFR sequence (GTINVHDVETQFNQYKTEAASRYNLTISDVSVSDVPFPFSAQSGA (SEQ ID NO:2)). Because the exact site of MUC1 cleavage depends on the enzyme that clips it, and that the cleavage enzyme varies depending on cell type, tissue type or the time in the evolution of the cell, the exact sequence of the MUC1* extra cellular domain may vary at the N-terminus.
Other clipped amino acid sequences may include SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:620); or SVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:621).
As used herein, the term “PSMGFR” is an acronym for Primary Sequence of MUC1 Growth Factor Receptor as set forth as GTINVHDVETQFNQYKTEAASRYNLTISDVSVSDVPFPFSAQSGA (SEQ ID NO:2). In this regard, the “N-number” as in “N-10 PSMGFR”, “N-15 PSMGFR”, or “N-20 PSMGFR” refers to the number of amino acid residues that have been deleted at the N-terminal end of PSMGFR. Likewise “C-number” as in “C-10 PSMGFR”, “C-15 PSMGFR”, or “C-20 PSMGFR” refers to the number of amino acid residues that have been deleted at the C-terminal end of PSMGFR.
As used herein, the “extracellular domain of MUC1*” refers to the extracellular portion of a MUC1 protein that is devoid of the tandem repeat domain. In most cases, MUC1* is a cleavage product wherein the MUC1* portion consists of a short extracellular domain devoid of tandem repeats, a transmembrane domain and a cytoplasmic tail. The precise location of cleavage of MUC1 is not known perhaps because it appears that it can be cleaved by more than one enzyme. The extracellular domain of MUC1* will include most of the PSMGFR sequence but may have an additional 10-20 N-terminal amino acids.
As used herein “sequence identity” means homology in sequence of a particular polypeptide or nucleic acid to a reference sequence of nucleic acid or amino acid such that the function of the homologous peptide is the same as the reference peptide or nucleic acid. Such homology can be so close with the reference peptide such that at times the two sequences may be 90%, 95% or 98% identical yet possess the same function in binding or other biological activities.
As used herein, “MUC1 positive” cell refers to a cell that expresses a gene for MUC1, MUC1-Y or MUC1-Z or other MUC1 variant.
As used herein, “MUC1 negative” cell refers to a cell that does not express a gene for MUC1.
As used herein, “MUC1* positive” cell refers to a cell that expresses a gene for MUC1, wherein that gene's expressed protein is a transmembrane protein that is devoid of tandem repeats, which may be a consequence of post-translational modification, cleavage, alternative splicing, or transfecting or transducing a cell with a MUC1 protein that is devoid of tandem repeats.
As used herein, “MUC1* negative” cell refers to a cell that may or may not express a gene for MUC1 but does not express a MUC1 transmembrane protein that is devoid of tandem repeats.
As used herein, “MUC1 positive” cancer cell refers to a cancer cell that overexpresses the gene for MUC1, expresses MUC1 in an aberrant pattern, wherein its expression is not restricted to the apical border and/or expresses a MUC1 that is devoid of tandem repeats.
As used herein, “MUC1 negative” cancer cell refers to a cancer cell that may or may not express a gene for MUC1 but does not overexpress MUC1 or does not overexpress a MUC1 transmembrane protein that is devoid of tandem repeats.
As used herein, “MUC1* positive” cancer cell refers to a cancer cell that overexpresses a MUC1 transmembrane protein that is devoid of tandem repeats.
As used herein, “MUC1* negative” cancer cell refers to a cancer cell that may or may not express a gene for MUC1 but does not overexpress a MUC1 transmembrane protein that is devoid of tandem repeats.
We discovered that a cleaved form of the MUC1 (SEQ ID NO:1) transmembrane protein is a growth factor receptor that drives the growth of over 75% of all human cancers. The cleaved form of MUC1, which we called MUC1* (pronounced muk 1 star), is a powerful growth factor receptor. Enzymatic cleavage releases the bulk of the MUC1 extracellular domain. It is the remaining portion comprising a truncated extracellular domain, transmembrane domain and cytoplasmic tail that is called MUC1*. Cleavage and release of the bulk of the extracellular domain of MUC1 unmasks a binding site for activating ligands dimeric NME1, NME6, NME8, NME7-AB, NME7-X1 or NME7. Cell growth assays show that it is ligand-induced dimerization of the MUC1* extracellular domain that promotes growth (
MUC1* is an excellent target for cancer drugs as it is aberrantly expressed on over 75% of all cancers and is likely overexpressed on an even higher percentage of metastatic cancers. After MUC1 cleavage, most of its extracellular domain is shed from the cell surface. The remaining portion has a truncated extracellular domain that at least comprises the primary growth factor receptor sequence, PSMGFR (SEQ ID NO:2). Antibodies that bind to the PSMGFR sequence and especially those that competitively inhibit the binding of activating ligands such as NME proteins, including NME1, NME6, NME8, NME7AB, NME7-X1 and NME7, are ideal therapeutics and can be used to treat or prevent MUC1 positive or MUC1* positive cancers, as stand-alone antibodies, antibody fragments or variable region fragments thereof incorporated into bispecific antibodies, or chimeric antigen receptors also called CARs, which are then transfected or transduced into immune cells, then administered to a patient.
Therapeutic anti-MUC1* antibodies can be monoclonal, polyclonal, antibody mimics, engineered antibody-like molecules, full antibodies or antibody fragments. Examples of antibody fragments include but are not limited to Fabs, scFv, and scFv-Fc. Human or humanized antibodies are preferred for use in the treatment or prevention of cancers. In any of these antibody-like molecules, mutations can be introduced to prevent or minimize dimer formation. Anti-MUC1* antibodies that are monovalent or bispecific are preferred because MUC1* function is activated by ligand induced dimerization. Typical binding assays show that NME1 and NME7-AB bind to the PSMGFR peptide portion of MUC1* (
Therapeutic anti-MUC1* antibodies for use as a stand alone antibody therapeutic or for integration into a BiTE or a CAR can be selected based on specific criteria. The parent antibody can be generated using typical methods for generating monoclonal antibodies in animals. Alternatively, they can be selected by screening antibody and antibody fragment libraries for their ability to bind to PSMGFR peptide (SEQ ID NO:2), a MUC1* peptide, which can be the SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:620); or SVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:621).
Resultant antibodies or antibody fragments generated or selected in this way can then be further selected by passing additional screens. For example, antibodies or antibody fragments become more preferred based on their ability to bind to MUC1* positive cancer cells or tissues but not to MUC1 negative cancer cells or to normal tissues. Further, anti-MUC1* antibodies or antibody fragments may be de-selected as anti-cancer therapeutics if they bind to stem or progenitor cells. Anti-MUC1* antibodies or antibody fragments become more preferred if they have the ability to competitively inhibit the binding of activating ligands to MUC1*.
A process for selecting anti-MUC1* antibodies for use in treating a patient diagnosed with a MUC1 positive cancer, at risk of developing a MUC1 positive cancer or suspected of having a MUC1 positive cancer comprises one or more of the following steps of selecting antibodies or antibody fragments that 1) bind to the PSMGFR peptide; 2) bind to the N-10 PSMGFR peptide; 3) bind to cancer cells; 4) do not bind to stem or progenitor cells; and 5) competitively inhibited the binding of dimeric NME1 or NME7-AB to the PSMGFR peptide. For example,
FACS scans show that anti-MUC1* antibodies MN-C2 and MN-E6 specifically bind to MUC1* positive solid tumor cancer cells and MUC1* transfected cells but not MUC1* negative or MUC1 negative cells. MNC3 and MNC8 bind to blood progenitor cells as well as to blood cancer cells, since these diseases are characterized by the inability of blood progenitor cells to terminally differentiate. Therefore, MNC3 and MNC8 are preferred for the treatment of blood cancers, as stand alone therapeutics, BiTEs or CAR T therapeutics. In one example, a humanized MN-C2 scFv is shown to bind to ZR-75-1, aka 1500, MUC1* positive breast cancer cells (
The Fabs of MN-E6 and MN-C2 or the comparable single chain variable regions derived from them potently inhibit the growth of MUC1* positive cancers in vitro and in vivo. In several examples, the Fabs of Anti-MUC1* antibodies inhibited the growth of human MUC1* positive cancers in vivo. In one case, immune-compromised mice were implanted with human breast tumors then treated with MN-E6 Fab after tumor engraftment.
In another aspect, MN-E6 was shown to halt the growth of prostate cancer.
Recombinant forms of MN-E6 and MINERVA-C2 were constructed that like the Fab are monomeric. In this case, MN-E6 was humanized and MINERVA-C2 was humanized. There are a number of methods known to those skilled in the art for humanizing antibodies. In addition to humanizing, libraries of human antibodies can be screened to identify other fully human antibodies that bind to the PSMGFR.
A single chain of the humanized MN-E6 variable region, called an scFv, was genetically engineered such that it was connected to the Fc portion of the antibody (SEQ ID NO:256 and 257). Fc regions impart certain benefits to antibody fragments for use as therapeutics. The Fc portion of an antibody recruits complement, which in general means it can recruit other aspects of the immune system and thus amplify the anti-tumor response beyond just inhibiting the target. The addition of the Fc portion also increases the half-life of the antibody fragment (Czajkowsky D M, Hu J, Shao Z and Pleass R J. (2012) Fc-fusion proteins: new developments and future perspectives. EMBO Mol Med. 4(10):1015-1028).
However, the Fc portion of an antibody homo-dimerizes, which in the case of anti-MUC1* antibody based therapeutics is not optimal since ligand-induced dimerization of the MUC1* receptor stimulates growth. As can be seen in
Some mutations or deletions were so effective that, even when loaded onto a gel at high concentrations, they resist dimer formation (
Like the parent mouse monoclonal antibodies, human or humanized antibodies as well as single chain constructs, scFv's, scFv-Fc fusions or scFv-Fc-mutants specifically bind to the synthetic MUC1* peptides (
The human or humanized anti-MUC1* antibody fragments described here specifically bind to MUC1 and MUC1* positive cancer cells.
In addition to binding to MUC1* positive cancer cells, the anti-MUC1* antibody variable region fragments, scFv's, scFv-Fc's and scFv-Fc-mutants inhibited growth of MUC1-positive cancer cells.
These data show that a human or humanized MN-E6 antibody or antibody fragment, Fab, MN-E6 scFv or hu MN-E6 scFv-FCmut are effective anti-cancer agents that can be administered to a person diagnosed with a MUC1 or MUC1* positive cancer, suspected of having a MUC1 or MUC1* positive cancer or is at risk of developing a MUC1 or MUC1* positive cancer.
In these specific examples, the dimer resistant Fc that was fused onto an antibody fragment or scFv is hu MN-E7 scFv. However, any of these Fc region mutations or combinations thereof that eliminate or minimize dimerization can be fused onto variable region fragments or single chain constructs of MN-E6, MN-C2, MN-C3 or MN-C8 or other antibodies identified that selectively bind to MUC1* as it exists on cancer cells or tissues. In addition, the Fabs of these antibodies can be used as an anti-cancer therapeutic. In one aspect of the invention, a person diagnosed with, suspected of having or is at risk of developing a MUC1* or MUC1 positive cancer is treated with an effective amount of human or humanized MN-E6 scFv, MN-C2 scFv, MN-C3 scFv, or MN-C8 scFv. In another aspect of the invention, a person diagnosed with, suspected of having or is at risk of developing a MUC1* or MUC1 positive cancer is treated with an effective amount of human or humanized MN-E6 scFv-FCY407R, MN-C2 scFv-FcY407R, MN-C3 scFv-FcY407R, or MN-C8 scFv-FcY407R. In another aspect of the invention, a person diagnosed with, suspected of having or is at risk of developing a MUC1* or MUC1 positive cancer is treated with an effective amount of human or humanized MN-E6 scFv-Fc mutantDhinge, MN-C2 scFv-Fc mutantDhinge, MN-C3 scFv-Fc mutantDhinge, or MN-C8 scFv-Fc mutantDhinge. In yet another aspect of the invention, a person diagnosed with, suspected of having or is at risk of developing a MUC1* or MUC1 positive cancer is treated with an effective amount of human or humanized MN-E6 scFv-Fc mutantY407R-Dhinge, MN-C2 scFv-Fc mutantY407R-Dhinge, MN-C3 scFv-Fc mutantY407R-Dhinge, or MN-C8 scFv-Fc mutantY407R-Dhinge. One aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a MUC1 positive or MUC1* positive cancer, wherein the patient is administered an effective amount of a monomeric MN-E6 scFv, MN-C2 scFv, MN-C3 scFv, MN-C8 scFv, or MN-E6 scFv-Fc, MN-C2 scFv-Fc, MN-C3 scFv-Fc, MN-C8 scFv-Fc, wherein the Fc portion of the antibody-like protein has been mutated such that it resists dimer formation.
Humanized antibodies or antibody fragments or fully human antibodies that bind to the extracellular domain of −MUC1* are preferred for therapeutic use. The techniques described herein for humanizing antibodies are but a few of a variety of methods known to those skilled in the art. The invention is not meant to be limited by the technique used to humanize the antibody.
Humanization is the process of replacing the non-human regions of a therapeutic antibody (usually mouse monoclonal antibody) by human one without changing its binding specificity and affinity. The main goal of humanization is to reduce immunogenicity of the therapeutic monoclonal antibody when administered to human. Three distinct types of humanization are possible. First, a chimeric antibody is made by replacing the non-human constant region of the antibody by the human constant region. Such antibody will contain the mouse Fab region and will contain about 80-90% of human sequence. Second, a humanized antibody is made by grafting of the mouse CDR regions (responsible of the binding specificity) onto the variable region of a human antibody, replacing the human CDR (CDR-grafting method). Such antibody will contain about 90-95% of human sequence. Third and last, a full human antibody (100% human sequence) can be created by phage display, where a library of human antibodies is screened to select antigen specific human antibody or by immunizing transgenic mice expressing human antibody.
A general technique for humanizing an antibody is practiced approximately as follows. Monoclonal antibodies are generated in a host animal, typically in mice. Monoclonal antibodies are then screened for affinity and specificity of binding to the target. Once a monoclonal antibody that has the desired effect and desired characteristics is identified, it is sequenced. The sequence of the animal-generated antibody is then aligned with the sequences of many human antibodies in order to find human antibodies with sequences that are the most homologous to the animal antibody. Biochemistry techniques are employed to paste together the human antibody sequences and the animal antibody sequences. Typically, the non-human CDRs are grafted into the human antibodies that have the highest homology to the non-human antibody. This process can generate many candidate humanized antibodies that need to be tested to identify which antibody or antibodies has the desired affinity and specificity.
Once a human antibody or a humanized antibody has been generated it can be further modified for use as an Fab fragment, as a full antibody, or as an antibody-like entity such as a single chain molecule containing the variable regions, such as scFv or an scFv-Fc. In some cases it is desirable to have Fc region of the antibody or antibody-like molecule mutated such that it does not dimerize.
In addition to methods that introduce human sequences into antibodies generated in non-human species, fully human antibodies can be obtained by screening human antibody libraries with a peptide fragment of an antigen. A fully human antibody that functions like MN-E6 or MN-C2 is generated by screening a human antibody library with a peptide having the sequence of the PSMGFR N-10 peptide. A fully human antibody that functions like MN-C3 or MN-C8 is generated by screening a human antibody library with a peptide having the sequence of the PSMGFR C-10 peptide.
Humanized anti-MUC1* antibodies were generated based on the sequences of the mouse monoclonal antibodies MN-E6, MN-C2, MN-C3 and MN-C8. In one aspect of the invention, a patient diagnosed with a MUC1* positive cancer is treated with an effective amount of humanized MN-E6, MN-C2, MN-C3 or MN-C8. In a preferred embodiment, a patient diagnosed with a MUC1* positive cancer is treated with an effective amount of humanized MN-E6 or MN-C2. In another aspect of the invention, a patient diagnosed with a MUC1* positive cancer is treated with an effective amount of humanized monovalent MN-E6, MN-C2, MN-C3 or MN-C8, wherein monovalent means the corresponding Fab fragment, the corresponding scFv or the corresponding scFv-Fc fusion. In a preferred embodiment, a patient diagnosed with a MUC1* positive cancer is treated with an effective amount of a humanized scFv or monomeric humanized scFv-Fc of MN-E6 or MN-C2. Since the MUC1* growth factor receptor is activated by ligand induced dimerization of its extracellular domain, and because the Fc portion of an antibody homo-dimerizes, it is preferable that a construct that includes an Fc portion uses a mutated Fc region that prevents or minimizes dimerization.
Antibodies that bind to PSMGFR (SEQ ID NO:2) peptide of the extracellular domain of the MUC1* receptor are potent anti-cancer therapeutics that are effective for the treatment or prevention of MUC1* positive cancers. They have been shown to inhibit the binding of activating ligands dimeric NME1 (SEQ ID NOS: 3 and 4) and NME7 (SEQ ID NOS: 5 and 6) to the extracellular domain of MUC1*. Anti-MUC1* antibodies that bind to the PSMGFR sequence inhibit the growth of MUC1*-positive cancer cells, specifically if they inhibit ligand-induced receptor dimerization. Fabs of anti-MUC1* antibodies have been demonstrated to block tumor growth in animals. Thus, antibodies or antibody fragments that bind to the extracellular domain of MUC1* would be beneficial for the treatment of cancers wherein the cancerous tissues express MUC1*.
Antibodies that bind to PSMGFR region of MUC1* or bind to a synthetic PSMGFR peptide are preferred. We have identified several monoclonal antibodies that bind to the extracellular domain of MUC1*. Among this group are mouse monoclonal antibodies MN-E6, MN-C2, MN-C3 and MN-C8, the variable regions of which were sequenced and are given as for MN-E6 SEQ ID NOS: 12-13 and 65-66, for MN-C2 SEQ ID NOS: 118-119 and 168-169, for MN-C3 SEQ ID NOS: 413-414 and 458-459 and for MN-C8 SEQ ID NOS: 505-506 and 543-554. The CDRs of these antibodies make up the recognition units of the antibodies and are the most important parts of the mouse antibody that should be retained when grafting into a human antibody. The sequences of the CDRs for each mouse monoclonal are as follows, heavy chain sequence followed by light chain: MN-E6 CDR1 (SEQ ID NO:16-17 and 69-70) CDR2 (SEQ ID NO:20-21 and 73-74) CDR3 (SEQ ID NO: 24-25 and 77-78), MN-C2 CDR1 (SEQ ID NO:122-123 and 172-173) CDR2 (SEQ ID NO:126-127 and 176-177) CDR3 (SEQ ID NO:130-131 and 180-181), MN-C3 CDR1 (SEQ ID NO:417-418 and 462-463) CDR2 (SEQ ID NO:421-422 and 466-467) CDR3 (SEQ ID NO:425-426 and 470-471), MN-C8 CDR1 (SEQ ID NO:507-508 and 545-546) CDR2 (SEQ ID NO:509-510 and 547-548) CDR3 (SEQ ID NO:511-512 and 549-550). In some cases, portions of the framework regions that by modeling are thought to be important for the 3-dimensional structure of the CDRs, are also imported from the mouse sequence.
Monoclonal antibodies MN-E6 and MN-C2 have greater affinity for MUC1* as it appears on cancer cells. Monoclonal antibodies MN-C3 and MN-C8 have greater affinity for MUC1* as it appears on stem cells. By sequence alignment the following human antibodies were chosen as being sufficiently homologous to the mouse antibody that substitution of the mouse CDRs would result in an antibody that retained ability to recognize the target. Mouse MN-E6 heavy chain variable region was homologous to human IGHV3-21*03 heavy chain variable region (SEQ ID NO: 26-27) and the light chain variable region was homologous to human IGKV3-11*02 light chain variable region (SEQ ID NO: 79-80). Mouse MN-C2 heavy chain variable region was homologous to human IGHV3-21*04 heavy chain variable region (SEQ ID NO: 132-133) and the light chain variable region was homologous to human IGKV7-3*01 light chain variable region (SEQ ID NO: 182-183). Mouse MN-C3 heavy chain variable region was homologous to human IGHV1-18*04 heavy chain variable region (SEQ ID NO: 427-428) and the light chain variable region was homologous to human IGKV2-29*03 light chain variable region (SEQ ID NO:472-473). Mouse MN-C8 heavy chain variable region was homologous to human IGHV3-21*04 heavy chain variable region (SEQ ID NO: 513-514) and the light chain variable region was homologous to human Z00023 light chain variable region (SEQ ID NO:551-552).
All four antibodies have been humanized, which process has resulted in several humanized forms of each antibody. CDRs derived from the variable regions of the mouse antibodies were biochemically grafted into a homologous human antibody variable region sequence. Humanized variable regions of MN-E6 (SEQ ID NOS: 38-39 and 93-94), MN-C2 (SEQ ID NOS: 144-145 and 194-195), MN-C3 (SEQ ID NOS: 439-440 and 486-487) and MN-C8 (SEQ ID NOS: 525-526 and 543-544) were generated by grafting the mouse CDRs into the variable region of a homologous human antibody. The humanized heavy chain variable constructs were then fused into constant regions of either human IgG1 heavy chain constant region (SEQ ID NOS:58-59) or human IgG2 heavy chain constant region (SEQ ID NO:54-55), which are then paired with either humanized light chain variable constructs fused to a human kappa chain (SEQ ID NO: 109-110) or human lambda chain (SEQ ID NO: 113-114) constant region. Other IgG isotypes could be used as constant region including IgG3 or IgG4.
Examples of humanized MN-E6 variable region into an IgG2 heavy chain (SEQ ID NOS:52-53) and into an IgG1 heavy chain (SEQ ID NOS:56-57), humanized MN-C2 variable into an IgG1 heavy chain (SEQ ID NOS: 158-159) or into an IgG2 heavy chain (SEQ ID NOS: 163-164) paired with either Lambda light chain (SEQ ID NO: 111-112 and 216-219) or Kappa chain (SEQ ID NO:107-108 and 210-213) and, humanized MN-C3 (SEQ ID NOS: 455-456, 453-454 and 500-501, 502-503) and MN-C8 (SEQ ID NOS: 541-542, 539-540 and 579-580, 581-582) antibodies were generated. Which IgG constant region is fused to the humanized variable region depends on the desired effect since each isotype has its own characteristic activity. The isotype of the human constant region is selected on the basis of things such as whether antibody dependent cell cytotoxicity (ADCC) or complement dependent cytotoxicity (CDC) is desired but can also depend on the yield of antibody that is generated in cell-based protein expression systems. In a preferred embodiment, humanized anti-MUC1* antibodies or antibody fragments are administered to a person diagnosed with or at risk of developing a MUC1-positive cancer.
One method for testing and selecting the humanized anti-MUC1* antibodies that would be most useful for the treatment of persons with cancer or at risk of developing cancers is to test them for their ability to inhibit the binding of activating ligands to the MUC1* extracellular domain. Dimeric NME1 can bind to and dimerize the MUC1* extracellular domain and in so doing stimulates cancer cell growth. Antibodies and antibody fragments that compete with NME1 for binding to the MUC1* extracellular domain are therefore anti-cancer agents. NME7 is another activating ligand of MUC1*. In some cases, it is preferable to identify antibodies that block the binding of NME7, or an NME7 truncation or cleavage product, to the MUC1* extracellular domain. Antibodies and antibody fragments that compete with NME7 and NME7 variants for binding to the MUC1* extracellular domain are effective as anti-cancer therapeutics. These antibodies include but are not limited to MN-E6, MN-C2, MN-C3, MN-C8 as well as single chain versions, such as scFv, of these antibodies and humanized version thereof. Other NME proteins also bind to MUC1 or MUC1* including NME6 and NME8. Antibodies that compete with these proteins for binding to MUC1* may also be useful as therapeutics. In a preferred embodiment, humanized anti-MUC1* antibodies or antibody fragments are administered to a person diagnosed with or at risk of developing a MUC1-positive cancer. In a more preferred embodiment, single chain antibody fragments, or monomeric scFv-Fc fusions, derived from humanized sequences of MN-E6 and MN-C2 are administered to a person diagnosed with or at risk of developing a MUC1-positive cancer.
Single chain variable fragments, scFv, or other forms that result in a monovalent antibody or antibody-like protein are also useful. In some cases it is desired to prevent dimerization of the MUC1* extracellular domain. Single chain variable fragments, Fabs and other monovalent antibody-like proteins have been shown to be effective in binding to the extracellular domain of MUC1* and blocking MUC1* dimerization. These single chain variable fragments, Fabs and other monovalent antibody-like molecules effectively blocked cancer growth in vitro and in animals xenografted with human MUC1-positive cancer cells. Thus, humanized single chain variable fragments or monovalent anti-MUC1* antibodies or antibody-like molecules would be very effective as an anti-cancer therapeutic. Such humanized single chain antibodies, Fabs and other monovalent antibody-like molecules that bind to the MUC1* extracellular domain or to a PSMGFR peptide are therefore useful as anti-cancer therapeutics. Anti-MUC1* single chain variable fragments are generated by grafting non-human CDRs of antibodies, which bind to extracellular domain of MUC1* or bind to PSMGFR peptide, into a framework of a homologous variable region human antibody. The resultant humanized heavy and light chain variable regions are then connected to each other via a suitable linker, wherein the linker should be flexible and of length that it allows heavy chain binding to light chain but discourages heavy chain of one molecule binding to the light chain of another. For example a linker of about 10-15 residues. Preferably, the linker includes [(Glycine)4 (Serine)1]3 (SEQ ID NOS: 401-402), but is not limited to this sequence as other sequences are possible.
In one aspect, the humanized variable regions of MN-E6 (SEQ ID NOS: 38-39 and 93-94), MN-C2 (SEQ ID NOS: 144-145 and 194-195), MN-C3 (SEQ ID NOS: 439-440 and 486-487) and MN-C8 (SEQ ID NOS: 525-526 and 565-566) are biochemically grafted into a construct that connects heavy and light chains via a linker. Examples of humanized single chain anti-MUC1* antibodies comprising humanized sequences from the variable regions of MN-E6, MN-C2, MN-C3 and MN-C8 were generated. Several humanized MN-E6 single chain proteins were generated (SEQ ID NOS: 232-237). Several humanized MN-C2 single chain proteins were generated (SEQ ID NOS: 238-243). Several humanized MN-C3 single chain proteins were generated (SEQ ID NOS: 244-249). Several humanized MN-C8 single chain proteins were generated (SEQ ID NOS: 250-255). In a preferred embodiment, humanized anti-MUC1* antibody fragments, including variable fragments, scFv antibody fragments MN-E6 scFv, MN-C2 scFv, MN-C3 scFv, or MN-C8 scFv are administered to a person diagnosed with or at risk of developing a MUC1-positive cancer. In a more preferred embodiment, single chain antibody fragments, such as variable fragments derived from humanized sequences of MN-E6 and MN-C2, are administered to a person diagnosed with or at risk of developing a MUC1-positive cancer.
In another aspect, the humanized variable regions of MN-E6 (SEQ ID NOS: 38-39 and 93-94), MN-C2 (SEQ ID NOS: 144-145 and 194-195), MN-C3 (SEQ ID NOS: 439-440 and 486-487) and MN-C8 (SEQ ID NOS: 525-526 and 565-566) are biochemically grafted into a single chain variable fragment, scFv, that also contains an Fc portion of an antibody. Examples of humanized single chain variable fragment of MN-E6, MN-C2, MN-C3 and MN-C8 fused to a Fc region of an antibody were generated (SEQ ID NOS: 256-257, 260-261, 264-265 and 268-269). Inclusion of an Fc region serves several purposes. It increases the molecular weight of the antibody fragment, which slows degradation and increases half-life. An Fc region also recruits immune system complement to the tumor site. Additionally, the addition of an antibody Fc region makes the scFv a convenient diagnostic tool, as the secondary antibodies detect and label the Fc portion. However, the Fc portion homo-dimerizes. Thus an scFv-Fc would be bivalent and could dimerize and activate the MUC1* growth factor receptor. In order to get the benefits of having an Fc attached to an anti-MUC1* scFv, without the drawback of inducing MUC1* dimerization, the Fc region was mutated to minimize or eliminate Fc homo-dimerization. The following mutations were made in the CH3 domain to create a monomeric scFv-Fc fusion protein: Y407R (SEQ ID NOS: 278 and 279), F405Q (SEQ ID NOS: 280 and 281), T394D (SEQ ID NOS: 282 and 283), T366W/L368W (SEQ ID NOD: 284 and 285), T364R/L368R (SEQ ID NOS: 286 and 285). Any combinations of those mutations can be tested and could be introduced into Fc (SEQ ID NOS: 272-273), CH2-CH3 (SEQ ID NOS: 274-275) or CH3 (SEQ ID NOS: 276-277) fusion proteins or in the hingeless Fc-fusion proteins (SEQ ID NOS: 288-289).
One aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a MUC1 positive or MUC1* positive cancer, wherein the patient is administered an effective amount of a monomeric MN-E6 scFv, MN-C2 scFv, MN-C3 scFv, MN-C8 scFv, or MN-E6 scFv-Fc, MN-C2 scFv-Fc, MN-C3 scFv-Fc, MN-C8 scFv-Fc, wherein the antibody variable fragment portions are human or have been humanized and wherein the Fc portion of the antibody-like protein has been mutated such that it resists dimer formation.
In another aspect of the invention, some or all of the single chain portions of anti-MUC1* antibody fragments are biochemically fused onto immune system molecules, using several different chimeric antigen receptor, ‘CAR’ strategies. The idea is to fuse the recognition portion of an antibody, typically as a single chain variable fragment, to an immune system molecule that has a transmembrane domain and a cytoplasmic tail that is able to transmit signals that activate the immune system. The recognition unit can be an antibody fragment, a single chain variable fragment, scFv, or a peptide. In one aspect, the recognition portion of the extracellular domain of the CAR is comprised of sequences from the humanized variable region of MN-E6 (SEQ ID NOS: 38-39 and 93-94), MN-C2 (SEQ ID NOS: 144-145 and 194-195), MN-C3 (SEQ ID NOS: 439-440 and 486-487) and MN-C8 (SEQ ID NOS: 525-526 and 565-566). In another aspect, it is comprised of sequences from a single chain variable fragment. Examples of single chain constructs are given. Several humanized MN-E6 single chain proteins, scFv, were generated (SEQ ID NOS: 232-237). Several humanized MN-C2 single chain proteins, scFv, were generated (SEQ ID NOS: 238-243). Several humanized MN-C3 single chain proteins, scFv, were generated (SEQ ID NOS: 244-249). Several humanized MN-C8 single chain proteins, scFv, were generated (SEQ ID NOS: 250-255). The transmembrane region of the CAR can be derived from CD8, CD4, antibody domains or other transmembrane region, including the transmembrane region of the proximal cytoplasmic co-stimulatory domain, such as CD28, 4-1BB or other. The cytoplasmic tail of the CAR can be comprised of one or more motifs that signal immune system activation. This group of cytoplasmic signaling motifs, sometimes referred to as, co-stimulatory cytoplasmic domains, includes but is not limited to CD3-zeta, CD27, CD28, 4-1BB, OX40, CD30, CD40, ICAm-1, LFA-1, ICOS, CD2, CD5, CD7 and Fc receptor gamma domain. A minimal CAR may have the CD3-zeta or an Fc receptor gamma domain then one or two of the above domains in tandem on the cytoplasmic tail. In one aspect, the cytoplasmic tail comprises CD3-zeta, CD28, 4-1BB and/or OX40.
Table 1 lists many of the anti-MUC1* CARs that we generated and tested. Several examples of MN-E6 CARs were generated: CAR MN-E6 CD3z (SEQ ID NOS: 294-295); CAR MN-E6 CD28/CD3z (SEQ ID NOS: 297-298); CAR MN-E6 4-1BB/CD3z (SEQ ID NOS: 300-301); CAR MN-E6 OX40/CD3z (SEQ ID NOS: 616-617); CAR MN-E6 CD28/OX40/CD3z (SEQ ID NOS: 618-619); CAR MN-E6 CD28/4-1BB/CD3z (SEQ ID NOS: 303-304). Several examples of humanized MN-C2 CARs were generated: CAR MN-C2 CD3z (SEQ ID NOS: 606-607); CAR MN-C2 CD28/CD3z (SEQ ID NOS: 608-609); CAR MN-C2 4-1BB/CD3z (SEQ ID NOS: 610-611); CAR MN-C2 OX40/CD3z (SEQ ID NOS: 612-613); CAR MN-C2 CD28/4-1BB/CD3z (SEQ ID NOS: 306-307); CAR MN-C2 CD28/OX40/CD3z (SEQ ID NOS: 614-615). Humanized MN-C3 CAR was generated: CAR MN-C3 4-1BB/CD3z (SEQ ID NOS: 600-601).
Several examples of humanized MN-E6 CARs with different hinge regions (SEQ ID NOS:345-360) were generated: CAR MN-E6-Fc/8/41BB/CD3z (SEQ ID NOS:310-311); CAR MN-E6 FcH/8/41BB/CD3z (SEQ ID NOS:315-316); CAR MN-E6 Fc/4/41BB/CD3z (SEQ ID NOS:318-319); CAR MN-E6 FcH/4/41BB/CD3z (SEQ ID NOS:321-322); CAR MN-E6 IgD/8/41BB/CD3z (SEQ ID NOS:323-324); CAR MN-E6 IgD/4/41BB/CD3z (SEQ ID NOS:327-328); CAR MN-E6 X4/8/41BB/CD3z (SEQ ID NOS:330-331); CAR MN-E6 X4/4/41BB/CD3z (SEQ ID NOS:333-334); CAR MN-E6 8+4/4/41BB/CD3z (SEQ ID NOS:336-337). In addition, several humanized MN-C3 single chain variable fragment and humanized MN-C8 single chain variable fragments were also generated.
Several CARs were also generated and tested wherein the targeting head of the CAR was derived from the anti-MUC1* antibody MNC2. CAR MN-C2-Fc/41BB/CD3z (SEQ ID NOS:732-733); CAR-MN-C2 IgD/Fc/4-1BB/CD3z (SEQ ID NOS:734-735); CAR MN-C2 FcH/41BB/CD3z (SEQ ID NOS:736-737); CAR-MN-C2 IgD/FcH/4-1BB/CD3z (SEQ ID NOS:738-739); CAR MN-C2 IgD/41BB/CD3z (SEQ ID NOS:740-741); CAR MN-C2 X4/41BB/CD3z (SEQ ID NOS:742-743).
The extracellular domain recognition unit of a MUC1* targeting CAR can comprise variable regions of any non-human, humanized or human antibody that is able to bind to at least 12 contiguous amino acids of the PSMGFR peptide (SEQ ID NO:2). In one aspect, the MUC1* targeting portion of the CAR comprises variable regions from non-human, humanized or human MN-E6, MN-C2, MN-C3 or MN-C8. In one aspect, the extracellular domain recognition unit of a CAR is comprised essentially of a humanized MN-E6, MN-C2, MN-C3 or MN-C8 single chain variable fragment scFv. The transmembrane region of the CAR can be derived from CD8 (SEQ ID NOS:363-364), or can be the transmembrane domain of CD3-zeta, CD28, 41bb, OX40 or other transmembrane region (SEQ ID NOS:361-372) and the cytoplasmic domain of a CAR with antibody fragment targeting MUC1* extracellular domain can be comprised of one or more selected from the group comprising an immune system co-stimulatory cytoplasmic domain. The group of immune system co-stimulatory domains includes but is not limited to CD3-zeta, CD27, CD28, 4-1BB, OX40, CD30, CD40, ICAm-1, LFA-1, ICOS, CD2, CD5, CD7 and Fc receptor gamma domain (SEQ ID NOS:373-382). Alternatively, the recognition unit portion of a CAR can comprise a peptide wherein the peptide binds to the target. NME7 binds to and activates MUC1*. In one aspect of the invention, the recognition unit of a CAR is a peptide derived from NME7 (SEQ ID NOS: 5-6) or a peptide derived from NME7, including but not limited to NME7 peptide A1 (SEQ ID NO: 7), NME7 peptide A2 (SEQ ID NO: 8), NME7 peptide B1 (SEQ ID NO: 9), NME7 peptide B2 (SEQ ID NO: 10) and NME7 peptide B3 (SEQ ID NO: 11).
Some strategies for generating CARs include a portion of the molecule that dimerizes with itself. In some cases, dimerization of the target is not desirable. Therefore, CARs can be constructed such that they heterodimerize. In one case the recognition unit of the first CAR binds to a first target while the recognition unit of the second CAR binds to a second target. Both recognition units can be antibody fragments, both can be peptides or one can be an antibody fragment and the other a peptide. A first target of the CAR can be the extracellular domain of MUC1*. The recognition unit of the CAR would be comprised of an antibody fragment that binds to MUC1* extracellular domain or to a PSMGFR peptide. Alternatively, the recognition unit of the CAR would be comprised of a peptide that binds to MUC1* extracellular domain, such peptides include peptides derived from an NME protein such as NME1 or NME7, more particularly NME7 derived peptides listed as SEQ ID NOS: 7-11. A second target of a heterodimeric CAR may be a peptide or antibody fragment that binds to NME7. Alternatively, a second target of a heterodimeric CAR may be a peptide or antibody fragment that binds to PD1 or its cognate ligand PDL-1 or other target ligand of the target cancer cell. A second target may be a peptide or antibody fragment that binds to NME1 or NME7-AB. Because it is desirable to prevent dimerization of MUC1 induced by a CAR, heterodimeric CARs can be constructed so that only the extracellular domain of one molecule has an extracellular recognition unit that binds to a target (SEQ ID NOS:584-587). The other molecule can have a truncated extracellular domain that is devoid of a target recognition unit or antibody fragment (SEQ ID NOS:588-599).
The CARs described can be transfected or transduced into a cell of the immune system. In a preferred embodiment, a MUC1* targeting CAR is transfected or transduced into a T cell. In one aspect, the T cell is a CD3+/CD28+ T cell. In another case it is a dendritic cell. In another case it is a B cell. In another case it is a mast cell. The recipient cell can be from a patient or from a donor. If from a donor, it can be engineered to remove molecules that would trigger rejection. Cells transfected or transduced with a CAR of the invention can be expanded ex vivo or in vitro then administered to a patient. Administrative routes are chosen from a group containing but not limited to bone marrow transplant, intravenous injection, in situ injection or transplant. In a preferred embodiment, the MUC1* targeting CAR is administered to a person diagnosed with or at risk of developing a MUC1-positive cancer.
There are many possible anti-MUC1* CAR constructs that can be transduced into T cells or other immune cells for the treatment or prevention of MUC1* positive cancers. CARs are made up of modules and the identity of some of the modules is relatively unimportant, while the identity of other modules is critically important.
Our experiments demonstrate that the antibody recognition fragment at the outermost portion of the CAR is critically important because it targets the immune cell bearing the CAR to the tumor site. The intracellular signaling motifs are also very important but can be interchanged.
We and others have shown that intracellular signaling modules, such as CD3-zeta (SEQ ID NOS: 373-376), CD28 (SEQ ID NOS: 377-378) and 41BB (SEQ ID NOS: 379-380), alone or in combinations stimulate immune cell expansion, cytokine secretion and immune cell mediated killing of the targeted tumor cells (Pule M A, Straathof K C, Dotti G, Heslop H E, Rooney C M and Brenner M K (2005) A chimeric T cell antigen receptor that augments cytokine release and supports clonal expansion of primary human T cells. Mol Ther. 12(5): 933-941; Hombach A A, Heiders J, Foppe M, Chmielewski M and Abken H. (2012) OX40 costimulation by a chimeric antigen receptor abrogates CD28 and IL-2 induced IL-10 secretion by redirected CD4(+) T cells. Oncoimmunology. 1(4):458-466; Kowolik C M, Topp M S, Gonzalez S, Pfeiffer T, Olivares S, Gonzalez N, Smith D D, Forman S J, Jensen M C and Cooper L J. (2006) CD28 costimulation provided through a CD19-specific chimeric antigen receptor enhances in vivo persistence and antitumor efficacy of adoptively transferred T cells. Cancer Res. 66(22): 10995-11004; Loskog A, Giandomenico V, Rossig C, Pule M, Dotti G and Brenner M K. (2006) Addition of the CD28 signaling domain to chimeric T-cell receptors enhances chimeric T-cell resistance to T regulatory cells. Leukemia. 20(10): 1819-1828; Milone M C, Fish J D, Carpenito C, Carroll R G, Binder G K, Teachey D, Samanta M, Lakhal M, Gloss B, Danet-Desnoyers G, Campana D, Riley J L, Grupp S A and June C H. (2009) Chimeric receptors containing CD137 signal transduction domains mediate enhanced survival of T cells and increased antileukemic efficacy in vivo. Mol Ther. 17(8): 1453-1464; Song D G, Ye Q, Carpenito C, Poussin M, Wang L P, Ji C, Figini M, June C H, Coukos G, Powell D J Jr. (2011) In vivo persistence, tumor localization, and antitumor activity of CAR-engineered T cells is enhanced by costimulatory signaling through CD137 (4-1BB). Cancer Res. 71(13):4617-4627). Less important is the identity of the short extracellular piece that presents the antibody fragment, the transmembrane domain, and the short cytoplasmic tail that comes before the intracellular signaling motifs.
The identity of the recognition antibody fragment that targets the CAR to a tumor is critically important. For the treatment of MUC1 positive or MUC1* positive cancers, that antibody recognition fragment must bind to the extracellular domain of portion of MUC1 that remains after cleavage and shedding of the bulk of the extracellular domain, which contains the tandem repeat domains. In one aspect of the invention, the portion that remains comprises the PSMGFR sequence. In another aspect of the invention, the portion of MUC1 that remains after cleavage and shedding contains the PSMGFR sequence plus up to nine (9) more amino acids extended at the N-terminus. In another aspect of the invention, the portion of MUC1 that remains after cleavage and shedding contains the PSMGFR sequence plus up to twenty one (21) more amino acids extended at the N-terminus. In one aspect, the antibody recognition fragment binds to at least twelve contiguous amino acids of a PSMGFR peptide. In another aspect of the invention, the antibody recognition fragment binds to a peptide comprising the sequence SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:620); or SVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:621).
As a demonstration, a single chain antibody fragment that included the variable domain of the monoclonal anti-MUC1* antibodies called MN-E6 or MN-C2 were engineered into a panel of CARs (Table 1). The MUC1* targeting CARs were then transduced, separately or in combinations, into immune cells. When challenged with surfaces presenting a MUC1* peptide, an antigen presenting cell transfected with MUC1*, or MUC1* positive cancer cells, the immune cells that were transduced with MUC1* targeting CARs elicited immune responses, including cytokine release, killing of the targeted cells and expansion of the immune cells (Table 2).
In one case, human Jurkhat cells were transduced with MUC1*-targeting CARs and upon exposure to a surface presenting the PSMGFR peptide, K562 antigen presenting cells that had been transfected with MUC1* or MUC1* positive cancer cells, the Jurkhat cells secreted IL-2. In another case, purified human T cells were transduced with MUC1*-targeting CARs and upon exposure to a surface presenting the PSMGFR peptide, K562 antigen presenting cells that had been transfected with MUC1* or MUC1* positive cancer cells, the T cells secreted IL-2, interferon gamma, and killed the targeted antigen presenting cells and cancer cells, while the T cells expanded. As demonstrated, CARs that comprise an antibody fragment, wherein the antibody fragment is able to bind to the PSMGFR peptide, a transmembrane domain and a cytoplasmic tail bearing co-stimulatory domains, elicit an immune system anti-tumor cell response when said CARs are transduced into immune cells, which include T cells. Therefore, other antibodies, antibody fragments or antibody mimics that are able to bind to the PSMGFR peptide will perform similarly and can be used to treat or prevent cancers. Those skilled in the art will recognize that there are a number of technologies available for transfecting or transducing cells with CARs and the invention is not limited by the method used for making the immune cell express a MUC1*-targeting CAR.
For example, the gene encoding the CARs and activated T cell induced genes described herein can be virally transduced into an immune cell using viruses, which may or may not result in the CAR gene being integrated into the genome of the recipient cell. Virus delivery systems and viral vectors including but not limited to retroviruses, including gamma-retroviruses, lentivirus, adenoviruses, adeno-associated viruses, baculoviruses, poxvirus, herpes simplex viruses, oncolytic viruses, HF10, T-Vec and the like can be used. In addition to viral transduction, CARs and activated T cell induced genes described herein can be directly spliced into the genome of the recipient cell using methods such as CRISPR technology, CRISPR-Cas9 and -CPF1, TALEN, Sleeping Beauty transposon system, and SB 100×.
Similarly, the identity of molecules that make up the non-targeting portions of the CAR such as the extracellular domain, transmembrane domain and membrane proximal portion of the cytoplasmic domain, are not essential to the function of a MUC1*-targeting CAR. For example, the extracellular domain, transmembrane domain and membrane proximal portion of the cytoplasmic domain can be comprised of portions of CD8, CD4, CD28, or generic antibody domains such as Fc, CH2CH3, or CH3. Further, the non-targeting portions of a CAR can be a composite of portions of one or more of these molecules or other family members.
One aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a MUC1 positive or MUC1* positive cancer, wherein the patient is administered an effective amount of immune cells that have been transduced with a MUC1* targeting CAR. In another aspect of the invention, the immune cells are T cells isolated from a patient, which are then transduced with CARs wherein the targeting head of the CAR binds to MUC1*, and after expansion of transduced T cells, the CAR T cells are administered in an effective amount to the patient. In yet another aspect of the invention, the immune cells are T cells isolated from a patient, which are then transduced with CARs wherein the targeting head of the CAR comprises portions of huMN-E6, huMN-C2, huMN-C3 or huMN-C8, and after optional expansion of transduced T cells, the CAR T cells are administered in an effective amount to the patient. In yet another aspect of the invention, the CAR that is transduced into the immune cell and administered to the patient diagnosed with a MUC1 or MUC1* positive cancer is chosen from the list of CARs in Table 1 or Table 2.
Many MUC1* targeting CARs were generated wherein the targeting antibody fragment at the distal end of the CAR was either MN-E6, MN-C2, MN-C3 or MN-C8. The DNA of each CAR was sequenced to verify that cloning was correctly done. Each construct was then shuffled into an expression plasmid, transfected into cells and then verified that the construct had successfully inserted by Western blot. Surface expression was verified by FACS. The MUC1* targeting CARs were then virally transduced into immune cells. In one aspect, they were transduced into Jurkat cells. In another aspect, they were transduced into primary human T cells that were purified from blood. A series of functional assays were performed and verified that the CARs were functional. Functional assays showed that both Jurkat cells and primary T cells transduced with MUC1* targeting CAR secreted the cytokine IL-2 and interferon gamma (IFN-g) when challenged with cells or surfaces presenting MUC1*. Table 1 lists the CARs that were made and tested. Table 2 lists cytokine release data for some of the CARs after transduction into human T cells and co-culture with a variety of cancer cells.
Another measure of function of CAR T cells is whether or not they induce killing of the targeted cells. T cells transfected with a variety of CARs comprising antibody fragments that bind to the PSMGFR sequence of MUC1* killed MUC1* expressing cells in co-culture assays. In one assay, target MUC1* expressing cells are incubated with calcein. When they are mixed with CAR T cells wherein the CAR comprises an antibody fragment such as MN-E6, MN-C2, MN-C3 or MN-C8 the CAR T cells kill the MUC1* presenting cells which causes the target cells to lyse and releases calcein into the supernatant.
As these experiments demonstrate, the critical portion of a CAR is the antibody fragment that directs the immune cell to the tumor cell. As we will show in the following section, MN-E6 and MN-C2 are specific for the form of MUC1* that is expressed on tumor cells. The next most important part of a CAR is the cytoplasmic tail bearing immune system co-stimulatory domains. The identity of these domains modulates the degree of immune response but does not affect the specificity. As shown, the identity of the transmembrane portion of a CAR is the least important. It appears that as long as the transmembrane portion has some flexibility and is long enough to allow the antibody fragment to reach its cognate receptor on the tumor cell, it will suffice. This is demonstrated in
The most accurate way of demonstrating antibody specificity is testing the antibody on normal human tissue specimens compared to cancerous tissue specimens. MN-C2 and MN-E6 were shown to specifically bind to MUC1 or MUC1* positive cancer cells. Several breast tumor arrays were assayed using several anti-MUC1 or MUC1* antibodies. Essentially the studies involving serial sections of breast cancer tissue specimens from over 1,200 different breast cancer patients showed that very little full-length MUC1 remains on breast cancer tissues. The vast majority of the MUC1 expressed is MUC1* and is stained by MN-C2. The analysis was performed by Clarient Diagnostics and tissue staining was scored using the Allred method. For example,
One aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a MUC1 positive or MUC1* positive cancer, wherein a specimen is obtained from the patient's cancer and is tested for reactivity with an antibody that binds to PSMGFR SEQ ID NO:2, SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:620) or SVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:621).
The patient is then treated with an scFv, scFv-Fc or CAR T that comprises antibody variable fragments from the antibody that reacted with their cancer specimen. Another aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a MUC1 positive or MUC1* positive cancer, wherein a specimen is obtained from the patient's cancer and is tested for reactivity with MN-E6-scFv, MN-C2-scFv, MN-C3-scFv or MN-C8-scFv; the patient is then treated with the scFv, scFv-Fc-mut or CAR T that comprises portions of the antibody that reacted with their cancer specimen.
We discovered that MUC1 can be cleaved to MUC1* by more than one cleavage enzyme and that the site of cleavage affects its fold and consequently affects which monoclonal antibody is able to recognize that form of MUC1*. Different cancer cells or cancerous tissues express different cleavage enzymes. We tested various cleavage enzyme inhibitors on different cancer cell lines and found that an inhibitor that inhibits cleavage of MUC1 in one cancer cell line did not inhibit its cleavage in another cancer cell line. Similarly, PCR experiments showed that cleavage enzymes are expressed at different levels in different cells or cell lines. For example, hematopoietic stem cells of the bone marrow express a MUC1* that is recognized by monoclonal antibody MNC3 but not MNE6 or MNC2 (
Divalent (or bivalent) single-chain variable fragments (di-scFvs, bi-scFvs) can be engineered by linking two scFvs. This can be done by producing a single peptide chain with two VH and two VL regions, yielding tandem scFvs. Another possibility is the creation of scFvs with linker peptides that are too short for the two variable regions to fold together (about five amino acids), forcing scFvs to dimerize. This type is known as diabodies. Diabodies have been shown to have dissociation constants up to 40-fold lower than corresponding scFvs, meaning that they have a much higher affinity to their target. Consequently, diabody drugs could be dosed much lower than other therapeutic antibodies and are capable of highly specific targeting of tumors in vivo. Still shorter linkers (one or two amino acids) lead to the formation of trimers, so-called triabodies or tribodies. Tetrabodies have also been produced. They exhibit an even higher affinity to their targets than diabodies.
All of these formats can be composed from variable fragments with specificity for two different antigens, in which case they are types of bispecific antibodies. The furthest developed of these are bispecific tandem di-scFvs, known as bi-specific T-cell engagers (BiTE antibody constructs). BiTEs are fusion proteins consisting of two scFvs of different antibodies, on a single peptide chain of about 55 kilodaltons. One of the scFvs may bind to T cells such as via the CD3 receptor, and the other to a tumor cell via a tumor specific molecule, such aberrantly expressed MUC1*.
Another aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a MUC1 positive or MUC1* positive cancer, wherein the patient is administered an effective amount of a BiTE wherein one antibody variable fragment of the BiTE binds to a T cell surface antigen and the other antibody variable fragment of the BiTE binds to PSMGFR SEQ ID NO:2, SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:620) or SVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:621). In one case, the antibody variable fragment of the BiTE that binds to MUC1* comprises portions of huMN-E6, huMN-C2, huMN-C3, or huMN-C8.
In another aspect of the invention, MUC1* peptides including PSMGFR SEQ ID NO:2, most or all of SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:620) or SVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:621) are used in adoptive T cell approaches. In this case, a patient's T cells are exposed to the MUC1* peptides and through various rounds of maturation, the T cells develop MUC1* specific receptors. The adapted T cells are then expanded and administered to the donor patient who is diagnosed with, suspected of having, or is at risk of developing a MUC1* positive cancer.
A series of CARs were also made that had MNC2 and humanized MNC2 as the extra cellular, targeting head of the CAR. The constructs for these CARs were inserted into a plasmid that was then inserted into a Lenti viral vector. Human T cells were then transduced with the lenti viral vector carrying the MNC2 CARS and huMNC2 CARs. MNC2-scFv-CARs that were mouse sequence or humanized were generated. CARs comprising MNC2-scFv and a variety of transmembrane and intracellular co-stimulatory domains were generated including constructs listed in Table 1. In one aspect of the invention, the CAR comprised huMNC2-scFv-short hinge region-transmembrane domain derived from CD8-short intracellular piece-4-1BB-3zeta. In another aspect, the transmembrane domain was derived from CD4 transmembrane sequence. In another aspect, the intracellular co-stimulatory domain was CD28-3zeta. In yet another aspect, the intracellular co-stimulatory domain was CD28-4-1BB-3zeta.
There are a variety of methods for assessing whether or not T cells recognize a target cell and are in the process of mounting an immune response. T cells cluster when they recognize a target or foreign cell. This can be readily seen with the naked eye or at low magnification. The appearance of CAR T cell clustering when co-cultured with target cancer cells is one measure of: a) whether or not they recognize the cells as target cells; and b) whether or not they are getting activated to attack the targeted cells, which in this case are cancer cells.
After T cells recognize and cluster target cells, they overexpress perforin and granzyme B. Together these two molecules activate a cell death pathway in the targeted cell. It is thought that the perforin makes a hole in the target cell into which the T cell injects granzyme B which then activates apoptotic proteases, causing the target cell to lyse.
Another measure of whether or not a T cell has recognized a target cell and is activated to kill that cell, is the upregulation of cytokines, especially interferon gamma (IFN-g). Table 2 lists the results of ELISA experiments measuring the amount of interferon gamma secreted by a variety of MUC1* targeting CAR T cells after co-culture with a variety of different cancer cells. To establish the link between MUC1* expression and CAR T activity, we performed an experiment to determine if the amount of CAR T killing was proportional to the amount of MUC1* expressed by the cancer cell. T47D is a highly MUC1* positive breast cancer cell. These cells also express some full-length MUC1. T47D cells were transfected with varying amounts of additional MUC1* then co-cultured with CAR T cells. The results showed that at low effector (CAR T) to target (cancer cells) ratios such as 1:1, specific CAR T killing increased with increasing MUC1* expression and the amount of secreted interferon gamma also increased with increasing MUC1* (
In addition to FACS analysis, many researchers now use an xCELLigence instrument to measure CAR T killing of cancer cells. FACS is not the best method for tracking T cell induced cell killing because the T cells lyse the target cell. By FACS it is difficult to measure dead cells because they are excluded as cell debris, so one must infer an amount of cell killing and by various methods determine if the missing cells are T cells or cancer cells.
The xCELLigence instrument uses electrode arrays upon which cancer cells are plated. The adherent cancer cells insulate the electrode and so cause an increase in impedance as they grow. Conversely, T cells are not adherent and remain in suspension so do not contribute to insulation of the electrode which would increase impedance. However, if the T cells or CAR T cells kill the cancer cells on the electrode plate, the cancer cells ball up and float off as they die, which causes the impedance to decrease. The xCELLigence instrument measures impedance as a function of time, which is correlated to cancer cell killing. In addition, the electrode plates also have a viewing window. When CAR T cells effectively kill the adsorbed target cancer cells, there is a decrease in impedance but also one can see that there are no cancer cells left on the plate surface.
These data demonstrate that T cells transduced with a CAR wherein the antibody fragment targeting head is MNC2, effectively kill MUC1* positive cancer cells. These data specifically show that huMNC2-scFV-CAR44 transduced into human T cells effectively kill MUC1* positive cancer cells. Because we and others have now demonstrated that the most important aspect of CAR T function is the targeting antibody fragment, it follows that an immune cell or a T cell transduced with any CAR having the antibody fragment MNC2-scFV or huMNC2-scFV would have similar efficacy against MUC1 or MUC1* positive tumors. For example, the hinge region that connects the scFv to the transmembrane portion could be any flexible linker. The intracellular co-stimulatory domains could be CD28-3zeta, CD28-4-1BB-3zeta or any combination of immune cell co-stimulatory domains.
Experiments were also performed exploring methods of pre-activating the CAR T cells to more effectively kill the target cancer cells. We first tested pre-stimulation of the CAR T cells using beads presenting anti-CD3 and anti-CD28 antibodies. This pre-stimulation increased the amount of cell killing but the increase was not specific for the target of the CAR. Rather, the CD3-CD28 stimulated CAR T cells non-specifically killed MUC1* positive and negative cells. We next tried pre-stimulating the CAR T cells with either beads or cancer cells that expressed the target of the antibody portion of the CAR. A synthetic MUC1*extra cellular domain peptide was attached to either 1 μm or 4.5 μm beads. Anti-MUC1* CAR T cells were incubated with the peptide presenting beads for 12-24 hours.
We also tested pre-activating CAR T cells by incubating them with cancer cells that present the target antigen. We incubated huMNC2-CAR44 T cells with HCT-MUC1* cells for 12-24 hours. This pre-stimulation was done once, twice, three or four times. Target cell pre-stimulation also greatly enhanced the specific killing of CAR T cells. As can be seen in
huMNC2-scFv-CAR44 transduced human T cell that were bead stimulated (Protocol 1) or cancer cell stimulated (Protocol 2) were tested for their ability to inhibit tumor growth in animals. Human cancer cells that had been stably transfected with Luciferase were injected into female NOD/SCID/GAMMA (NSG) mice between 11 and 15 weeks of age. In one experiment, 500,000 HCT-MUC1* cancer cells were injected sub-cutaneously into a rear flank. Tumor engraftment was verified by injecting the animals with Luciferin and then imaging the fluorescent cancer cells using an IVIS instrument. IVIS images taken Day 5 post implantation showed the presence of tumor cells. On Day 6 and on Day 12, 10M huMNC2-scFv-CAR44 T cells were administered to the animals. 5M of the CAR T cells were administered by intratumor injection and the other 5M were administered by tail vein injection. Control groups were injected by same administration routes with either the same number of untransduced T cells or same volume of PBS. IVIS measurements of tumor burden were taken on Days 7, 11, 13, and 21. As can be seen in
huMNC2-scFv-CAR44 transduced human T cell that were bead stimulated (Protocol 1) or cancer cell stimulated (Protocol 2) were also tested for their ability to inhibit tumor growth in animals. Human cancer cells that had been stably transfected with Luciferase were injected into female NOD/SCID/GAMMA (NSG) mice between 11 and 15 weeks of age. In another experiment, 500,000 BT-20 MUC1* positive triple negative breast cancer cells were injected sub-cutaneously into a rear flank. Tumor engraftment was verified by injecting the animals with Luciferin and then imaging the fluorescent cancer cells using an IVIS instrument. IVIS images taken Day 6 post implantation showed the presence of tumor cells. On Day 6, after IVIS imaging, 10M huMNC2-scFv-CAR44 T cells were administered to the animals. 5M of the CAR T cells were administered by intratumor injection and the other 5M were administered by tail vein injection. Control group was injected by same administration routes with the same number of untransduced T cells. IVIS measurements of tumor burden were taken on Days 6, 8, and 12. As can be seen in
huMNC2-scFv-CAR44 transduced human T cell that were bead stimulated (Protocol 1) were also tested for their ability to inhibit ovarian cancer growth in animals. Human SKOV-3 MUC1* positive ovarian cancer cells that had been stably transfected with Luciferase were injected into female NOD/SCID/GAMMA (NSG) mice between 11 and 15 weeks of age. In one experiment, 500,000 SKOV-3 cancer cells were injected into the intraperitoneal cavity to mimic metastatic ovarian cancer in humans. Tumor engraftment was verified by injecting the animals with Luciferin and then imaging the fluorescent cancer cells using an IVIS instrument. IVIS images taken Day 3 post implantation showed the presence of tumor cells. On Day 4 and Day 11, post tumor implantation, 10M huMNC2-scFv-CAR44 T cells were IP administered to the animals. On Day 4, CAR T cells were IP injected. On Day 11 half the CAR T cells were injected into the intraperitoneal space and the other half was injected into the tail vein. Control groups were injected by same administration routes with either the same number of untransduced T cells or same volume of PBS. Subsequent IVIS measurements of tumor burden were taken on Day 7, Day 10 and Day 15. As can be seen in
One aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a MUC1 positive or MUC1* positive cancer, wherein the patient is administered an effective amount of immune cells that have been transduced with a MUC1* targeting CAR, wherein the CAR is chosen from among the group consisting of MN-E6-CD8-3z (SEQ ID NOS:294-295); MN-E6-CD4-3z (SEQ ID NOS:746-747); MN-E6-CD8-CD28-3z (SEQ ID NOS:297-298); MN-E6-CD4-CD28-3z (SEQ ID NOS:748-749); MN-E6-CD8-41BB-3z (SEQ ID NOS:300-301); MN-E6-CD4-41BB-3z (SEQ ID NOS:750-751); MN-E6-CD8-CD28-41BB-3z (SEQ ID NOS:303-304); MN-E6-CD4-CD28-41BB-3z (SEQ ID NOS:754-755); MN-E6scFv-Fc-8-41BB-CD3z (SEQ ID NOS:310-311); MN-E6scFv-IgD-Fc-8-41BB-CD3z (SEQ ID NOS:770-771); MN-E6scFv-FcH-8-41BB-CD3z (SEQ ID NOS:315-316); MN-E6scFv-IgD-FcH-8-41BB-CD3z (SEQ ID NOS:772-773); MN-E6scFv-Fc-4-41BB-CD3z (SEQ ID NOS:318-319); MN-E6scFv-FcH-4-41BB-CD3z (SEQ ID NOS:321-322); MN-E6scFv-IgD-8-41BB-CD3z (SEQ ID NOS:323-324); MN-E6scFv-IgD-4-41BB-CD3z (SEQ ID NOS:327-328); MN-E6scFv-X4-8-41BB-CD3z (SEQ ID NOS:330-331); MN-E6scFv-X4-4-41BB-CD3z (SEQ ID NOS:333-334); MN-E6scFv-8-4-41BB-CD3z (SEQ ID NOS:336-337), or any of the aforementioned CARs wherein the MN-E6 is replaced by MN-C2, MN-C3 or MN-C8; MN-C2-CD8-3z (SEQ ID NOS:606-607); MN-C2-CD4-3z (SEQ ID NOS:758-759); MN-C2-CD8-CD28-3z (SEQ ID NOS:608-609); MN-C2-CD4-CD28-3z (SEQ ID NOS:760-761); MN-C2-CD8-41BB-3z (SEQ ID NOS:610-611 and SEQ ID NOS:718-719); MN-C2-CD4-41BB-3z (SEQ ID NOS:762-763); MN-C2-CD8-CD28-41BB-3z (SEQ ID NOS:306-307); MN-C2-CD4-CD28-41BB-3z (SEQ ID NOS:766-767); MN-C2-Fc-8-41BB-CD3z (SEQ ID NOS:732-733); MN-C2-IgD-Fc-8-41BB-CD3z (SEQ ID NOS:734-735); MN-C2-FcH-8-41BB-CD3z (SEQ ID NOS:736-737); MN-C2-IgD-FcH-8-41BB-CD3z (SEQ ID NOS:738-739); MN-C2-IgD-8-41BB-CD3z (SEQ ID NOS:740-741); MN-C2-X4-8-41BB-CD3z (SEQ ID NOS:742-743). Another aspect of the invention is a method for treating a patient diagnosed with, suspected of having, or at risk of developing a cancer, wherein the patient is administered an effective amount of immune cells that have been transduced with one of the aforementioned CARs wherein the MN-E6 is replaced by a peptide comprising antibody variable domain fragments that are specific for a cancer antigen. In any of the above methods, the immune cell may be a T cell and may further be isolated from the patient to be treated.
It is known that MUC1 is cleaved to the growth factor receptor form, MUC1*, on some healthy cells in addition to cancer cells. For example, MUC1 is cleaved to MUC1* on healthy stem and progenitor cells. A large percentage of bone marrow cells are MUC1* positive. Portions of the intestine are MUC1* positive.
The inventors have discovered that MUC1 can be cleaved at different positions that are relatively close to each other but the location of cleavage changes the fold of the remaining portion of the extracellular domain. As a result, monoclonal antibodies can be identified that bind to MUC1* cleaved at a first position but do not bind to MUC1* that has been cleaved at a second position. This discovery is disclosed in WO2014/028668, filed Aug. 14, 2013, the contents of which are incorporated by reference herein its entirety. We identified a set of anti-MUC1* monoclonal antibodies that bind to MUC1* as it appears on cancer cells but do not bind to MUC1* as it appears on stem and progenitor cells. Conversely, we identified a second set of monoclonal antibodies that bind to stem and progenitor cells but do not bind to cancer cells. One method used to identify stem specific antibodies is as follows: supernatants from monoclonal hybridomas were separately adsorbed onto 2 multi-well plates. Stem cells, which are non-adherent cells, were put into one plate and cancer cells which are adherent were put into an identical plate. After an incubation period, the plates were rinsed and inverted. If the non-adherent stem cells stuck to the plate, then the monoclonal antibody in that particular well recognizes stem cells and will not recognize cancer cells. Antibodies that did not capture stem cells or antibodies that captured cancer cells were identified as cancer specific antibodies. FACS analysis has confirmed this method works.
Antibodies MN-E6 and MN-C2 are examples of cancer-specific antibodies. Antibodies MN-C3 and MN-C8 are examples of stem-specific antibodies. Although both sets of antibodies are able to bind to a peptide having the PSMGFR sequence, FACS analysis shows that the anti-MUC1* polyclonal antibody and MN-C3 bind to MUC1* positive bone marrow cells but MN-E6 does not. The MUC1* polyclonal antibody was generated by immunizing a rabbit with the PSMGFR peptide. Similarly, MN-C3 binds to stem cells of the intestinal crypts but MN-E6 does not. Conversely, MN-E6 antibody binds to cancerous tissue while the stem-specific MN-C3 does not. Competition ELISA experiments indicate that the C-terminal 10 amino acids of the PSMGFR peptide are required for MN-E6 and MN-C2 binding, but not for MN-C3 and MN-C8. Therefore, another method for identifying antibodies that are cancer specific is to immunize with a peptide having the sequence of the PSMGFR peptide minus the 10 N-terminal amino acids or use that peptide to screen for antibodies or antibody fragments that will be cancer specific. Antibodies that bind to a peptide with a sequence of PSMGFR peptide minus the N-terminal 10 amino acids but do not bind to a peptide with a sequence of PSMGFR peptide minus the C-terminal 10 amino acids are cancer specific antibodies for use in the treatment or prevention of cancers.
The extracellular domain of MUC1 is also cleaved on stem cells and some progenitor cells, where activation of cleaved MUC1 by ligands NME1 in dimer form or NME7 promotes growth and pluripotency and inhibits differentiation. The transmembrane portion of MUC1 that remains after cleavage is called MUC1* and the extracellular domain is comprised essentially of the Primary Sequence of MUC1 Growth Factor Receptor (PSMGFR) sequence. However, the exact site of cleavage can vary depending on cell type, tissue type, or which cleavage enzyme a particular person expresses or overexpresses. In addition to the cleavage site that we previously identified which leaves the transmembrane portion of MUC1* comprising most or all of the PSMGFR SEQ ID NO:2, other cleavage sites result in an extended MUC1* comprised of most or all of SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:620); or SVVVQLTLAFREGTINVHDVETQFNQYKTEAASRY (SEQ ID NO:621). The site of MUC1 cleavage affects how the remaining extracellular domain folds. We have identified monoclonal antibodies that bind to cleaved MUC1* on cancer cells but do not bind to cleaved MUC1* as it exists on healthy stem and progenitor cells.
Whereas an anti-MUC1* antibody or antibody-like molecule may be most effective if it competitively inhibits the binding of NME1, NME6, NME8 or NME7 or NME7-AB to MUC1*, for example an antibody that binds to the PSMGFR sequence especially if said antibody is unable to bind to a PSMGFR peptide if the 10 C-terminal amino acids are missing, antibodies or antibody-like molecules that carry a payload need not competitively inhibit the binding of MUC1* ligands to be effective as anti-cancer agents. For example antibodies or antibody-like molecules that are conjugated to a toxin could be effective at killing target cancer cells without necessarily inhibiting binding of the activating ligands. For example, antibodies or antibody-like molecules incorporated into CAR Ts or BiTEs which recruit the patient's immune system to the tumor can be effective as anti-cancer agents even if the antibody fragment targets a portion of MUC1* such that antibody fragment binding does not competitively inhibit the binding of NME1, NME6, NME8, NME7-AB or NME7. In a preferred embodiment the antibody fragment incorporated into a CAR, an adaptive T cell receptor or a BiTE competitively inhibits the binding of NME1, NME6, NME8, NME7-AB or NME7 to MUC1*.
Antibodies that are able to bind to the extracellular domain of the remaining transmembrane portion block the interaction between the MUC1* extracellular domain and activating ligands and in this way can be used as therapeutic agents, for example for the treatment of cancers. Anti-MUC1* antibodies are also useful for the growth, delivery, identification or isolation of stem cells both in vitro and in vivo.
General Strategy for Using Antibodies, Antibody Fragments and CARs that Target the Extracellular Domain of MUC1*
Monoclonal antibodies MN-C3 and MN-C8 have a greater binding affinity for blood cells than solid tumor cancer cells. Humanized antibodies and antibody fragments containing sequences derived from the variable regions of MN-C3 and MN-C8 can be used as a stand alone therapy or integrated into CAR Ts, BiTEs, ADCs for the treatment of blood cancers.
Alternatively, humanized antibodies and antibody fragments containing sequences derived from the variable regions of MN-C3 and MN-C8 can be used to deliver stem cells to a specific location such as for in situ human therapeutics. In one case, a substrate coated with humanized MN-C3 or MN-C8 derived antibodies or antibody fragments is loaded with stem cells then inserted into a patient. In another case, a substrate coated with humanized MN-C3 or MN-C8 derived antibodies or antibody fragments is inserted into a patient in order to recruit the patient's own stem cells to a specific area for therapy. Human therapies in which antibodies that bind to human stem cells will be of therapeutic use include spinal cord repair. Substrates coated with humanized MN-C3 or MN-C8 derived antibodies or antibody fragments are also used to identify or isolate human antibodies. Humanized MN-C3 or MN-C8 derived antibodies can also be used to stimulate the growth of stem cells.
Many applications of CAR T therapy are limited by the length or flexibility of the extracellular domain between the T cell membrane and the antibody fragment that will direct the T cell to the desired location. For example, the surface of solid tumor cancer cells is populated with a myriad of cell surface proteins and growth factor receptors. Many of these cell surface proteins have bulky extracellular domains that limit the access of immune cells, such as T cells or CAR T cells, to the tumor cell surface. In one example, MUC1 and the cleaved growth factor receptor form MUC1* are overexpressed on over 75% of solid tumor cancers and on some blood cancers. The extracellular domain of MUC1 full-length contains between about 1,500 and 2,500 amino acids while the extracellular domain of MUC1* contains only about 45 to 65 amino acids. Variability in the length of MUC1 full-length is due to variability in the number of tandem repeat units that are expressed. Variability in the length of MUC1* is due to different cleavage sites when MUC1 is cleaved by different cleavage enzymes. Whereas it is most desirable to get the T cell close to the surface of the cancer cell, access can be sterically hindered by neighboring proteins, including full-length MUC1, that have large and bulky extracellular domains. This is especially true for early stage cancers. Tissue studies show that early stage cancers have more full-length MUC1 than late stage cancers that can be devoid of any full-length MUC1. This problem can in some cases severely limit the efficacy of cancer immunotherapies, including CAR T, adaptive T cell therapy, BiTEs and other T cell engagers.
One solution to this problem is to express or activate cleavage enzymes in the area of the targeted tumor cells to cleave the bulky proteins that restrict access of T cells to the tumor.
In one aspect of the invention, the cleavage enzyme and the CAR are transduced into the same T cell. In another aspect of the invention, the cleavage enzyme is on an inducible promoter such that its expression is activated when the CAR engages the targeted cancer cells. In some cases, the expression of the cleavage enzyme is controlled by an inducible promoter. In one aspect of the invention, expression of the cleavage enzyme is induced when the immune cell is activated, for example when it recognizes or engages its target. In one example, a T cell is transfected or transduced with a cleavage enzyme whose expression is induced when the T cell recognizes a target cancer cell. One way to do this is to induce expression of the cleavage enzyme when, or shortly after, an NFAT protein is expressed or translocated to the nucleus. For example, a sequence derived from an NFAT promoter region is put upstream of the gene for the cleavage enzyme. In this way, when the transcription factors that bind to the promoter of the NFAT protein are present in sufficient concentration to bind to and induce transcription of the NFAT protein, they will also bind to that same promoter that is engineered in front of the sequence for transcription of the cleavage enzyme. The NFAT protein may be NFAT1 also known as NFATc2, NFAT2 also known as NFATc or NFATc1, NFAT3 also known as NFATc4, NFAT4 also known as NFATc3, or NFAT5. In one aspect of the invention, the NFAT is NFATc1, NFATc3 or NFATc2. In one aspect of the invention, the NFAT is NFAT2 also known as NFATc1. SEQ ID NO:646 shows nucleic acid sequence of the upstream transcriptional regulatory region for NFAT2. The promoter sequence for NFAT gene may include the nucleic acid sequence of SEQ ID NO:781-783 or SEQ ID NO:815 as examples, but it can be seen that the optimal sequence or minimal sequence for expression of the cleavage enzyme may be obtained by making fragments, extensions or mutations of the promoter and testing for the strength of the promoter with respect to expression of the cleavage enzyme. In one aspect of the invention, the transcriptional regulatory region for NFAT2 is engineered upstream of the gene encoding the cleavage enzyme MMP9 (SEQ ID NO:647) or the catalytic sub-unit of MMP9 (SEQ ID NO:648). In one aspect of the invention, the NFAT is NFATc3 and the promoter sequence of NFATc3 includes nucleic acid sequences from SEQ ID NO:816. In one aspect of the invention, the transcriptional regulatory region for NFATc3 is engineered upstream of the gene encoding the cleavage enzyme MMP9 (SEQ ID NO:647) or the catalytic sub-unit of MMP9 (SEQ ID NO:648). In another aspect of the invention, the NFAT is NFATc2. SEQ ID NO:817-818 shows nucleic acid sequence of the upstream transcriptional regulatory region for NFATc2. In one aspect of the invention, the transcriptional regulatory region for NFATc2 is engineered upstream of the gene encoding the cleavage enzyme MMP9 (SEQ ID NO:647) or the catalytic sub-unit of MMP9 (SEQ ID NO:648).
Another method for having the expression of the cleavage enzyme induced when the T cell or CAR T cell is activated is to have the gene for the cleavage enzyme on an inducible promoter where the NFAT protein itself binds to and induces transcription of the cleavage enzyme. In this case, an NFAT response element (NFAT RE) may be positioned upstream of the gene for the cleavage enzyme or fragment of the cleavage enzyme. The NFAT may bind to its responsive element upstream of the cleavage enzyme alone or as part of a complex. The NFAT protein may be NFATc1, NFATc2, NFATc3, NFATc4, or NFAT5. In a preferred embodiment, the NFAT protein is NFAT2 aka NFATc1, aka NFATc. The gene of the cleavage enzyme or fragment thereof is cloned downstream of an NFAT-response element (SEQ ID NO:649), which may be repeats of the response element (SEQ ID NO:650) and CMV minimal promoter (mCMV) (SEQ ID NO:651) to induce expression of cleavage enzyme by NFAT protein. The NFAT response element may include nucleic acid sequence of NFAT consensus sequence (SEQ ID NO:804). The NFAT response element may include the nucleic acid sequence of SEQ ID NOS:805-814 as examples, but it can be seen that the optimal sequence or minimal sequence for expression of the cleavage enzyme may be obtained by making fragments, extensions or mutations of the responsive element nucleic acid and testing for the strength of the responsive element with respect to expression of the cleavage enzyme. The enhancer region of Foxp3 also contains NFAT response elements within the 120-bp from 2079 to 2098 (SEQ ID NO:821). The NFAT response element may include nucleic acid NFAT consensus sequence of (5′-cattttttccat-3′) (SEQ ID NO:819) or (5′-tttttcca-3′) (SEQ ID NO:820), which NFATc1 specifically binds to (Xu et al., Closely related T-memory stem cells correlate with in vivo expansion of CAR. CD19-T cells and are preserved by IL-7 and IL-15, Blood 2014 123:3750-3759), or repeats thereof. The NFAT response elements may also be separated by nucleic acid spacer sequences. Other NFAT responsive elements may exist and may further be discovered, and a skilled artisan in the art when directed to determine NFAT responsive element may do so by carrying out molecular biological assays to obtain it given the guidance of at least the responsive elements as set forth as SEQ ID NOS: 804-814 albeit as only mere examples. In one aspect of the invention, the cleavage enzyme that is downstream of the NFAT-response element and CMV minimal promoter is MMP9 (SEQ ID NO:652). In another aspect of the invention, the cleavage enzyme is a catalytic sub-unit of MMP9 (SEQ ID NO:653).
Because NFATs 1-4 are regulated by the calcineurin pathway, potential toxicities that may arise in a patient can be stopped by treatment with an immunosuppressive agent such as FK506, Cyclosporin, Cyclosporin A, or Tacrolimus that block calcineurin activity and inhibit NFAT translocation to the nucleus. The T cell transduced or transfected with a cleavage enzyme on an inducible promoter may also be transfected or transduced with a CAR that recognizes a protein or molecule on the cancer cell. In a specific example, the cleavage enzyme is one that is able to cleave MUC1 full-length and the CAR bears an antibody fragment that directs it to MUC1* on the surface of cancer cells.
To determine which cleavage enzymes cleave MUC1 on cancer cells, we tested a series of MMP and ADAM enzyme inhibitors. These experiments pointed to MMP9 as being an important cleavage enzyme in cancer cells. To confirm that MMP9 cleaves MUC1 on cancer cells, we transfected HCT-116 MUC1 negative colon cancer cells with a mimic of full-length MUC1 having 41 tandem repeat domains: HCT-MUC1-41TR. Through single cell cloning we were able to establish this cell line wherein MUC1 only minimally gets cleaved to MUC1*.
In one aspect of the invention, an immune cell is transduced with both a CAR to target the immune cell to the tumor, and a cleavage enzyme. The CAR and the cleavage enzyme can be encoded on the same plasmid or on two different plasmids. In one aspect, the cleavage enzyme is on an inducible promoter. In another aspect, expression of the cleavage enzyme is induced by a protein that is expressed when the immune cell is activated. In one case, expression of the cleavage enzyme is induced by an NFAT protein. In another aspect, expression of the cleavage enzyme is induced by NFATc1. In another aspect, expression of the cleavage enzyme is induced when one of the NFAT proteins binds to an NFAT response element that is inserted upstream of the gene for the cleavage enzyme or a catalytically active fragment thereof. In one aspect, the cleavage enzyme is MMP9 or a fragment of MMP9 that is catalytically active.
In one aspect of the invention, the cleavage enzyme is MMP9 (SEQ ID NO:643). Some cleavage enzymes are naturally expressed as pro-enzymes that need to be activated. This can be accomplished by biochemical means, by expressing a co-enzyme that activates a cleavage enzyme or by engineering the enzyme in an activated form. The invention anticipates overcoming this problem by co-expressing the cleavage enzyme with its activator. In one aspect of the invention, the cleavage enzyme is MMP9 and the co-activator is MMP3. In another aspect of the invention, the cleavage enzyme is expressed in a form that is already active, for example by expressing a fragment of the cleavage enzyme that still has catalytic function. In one case, the cleavage enzyme is an MMP9 fragment that is catalytically active. One example of an MMP9 catalytic fragment is given as SEQ ID NO:645.
MMP9, which must be activated by MMP3, is overexpressed in a large percentage of solid tumors. Further, it is known that MNC2 anti-MUC1* monoclonal antibody recognizes MUC1 after it is cleaved by MMP9. The breast, ovarian, pancreatic and lung cancer arrays that were shown in
APMA is a biochemical that activates MMPs. We used APMA along with the conditioned media of cells that we transfected with either MMP9 or ADAM17 to see if any of these cleavage enzymes would cleave MUC1 on the HCT-MUC1-41TR cell line that only expresses full-length MUC1. As controls, we also tested the enzymes on HCT-MUC1* cells. The MUC1 and MUC1* expressing cells were stained with a red dye, CMTMR. Human T cells that were transduced with an anti-MUC1* CARs, CAR44 or CAR50 were co-cultured with the cancer cells. Untransduced T cells were used as a control. As can be seen in
We performed the same experiment, this time using T47D breast cancer cells that were hard to kill using anti-MUC1* CAR T cells presumably because they express high levels of full-length MUC1 as well as MUC1*. As can be seen in
In another example, T47D MUC1 positive tumor cells were incubated with a recombinant catalytic domain of MMP9 (Enzo Life Sciences, Inc., Farmingdale, NY) at either 100 ng/mL or 500 ng/mL. Western blot analysis showed that the MUC1/MUC1* positive cancer cells underwent extensive cleavage of MUC1 to MUC1*. In another example, T47D breast cancer cells were pre-incubated with a human recombinant MMP9 catalytic domain protein then co-cultured with anti-MUC1* CAR44 T cells. The specific killing of the T47D cells by CAR44 T cells was monitored in real-time on an xCelligence instrument that measures impedance as a function of time. This analysis uses electrode arrays upon which cancer cells are plated. The adherent cancer cells insulate the electrode and cause an increase in impedance as they grow. Conversely, T cells are not adherent and remain in suspension so do not increase or decrease impedance. However, if the T cells or CAR T cells kill the cancer cells on the electrode plate, the cancer cells ball up and float as they die, which causes the impedance to decrease. The addition of MMP9 catalytic domain dramatically increased the killing of T47D cancer cells.
A convenient method for testing the presence of MMP9 is with a fluorogenic assay, for example using the OMNIMMP peptide assay kit. The kits have a peptide that is an MMP9 substrate that has been derivatized with a masked fluorophore. When MMP9 is added to a solution containing the peptide, MMP9 cleaves the peptide at a position that unmasks the fluorophore and the fluorescence can be read on a plate reader. MMP-9 activity is read in Relative Fluorescent Units (RFUs) which is an arbitrary value related to the amount of light detected by a plate reader set to excite each well containing samples at 328 nm and measure the emission at 393 nm. An increase in RFUs indicates cleavage of the Gly-Leu bond, unmasking of the fluorophore and therefore the presence of MMP-9. The sequence of the OMNIMMP peptide is Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2. AcOH [Mca=(7-methoxycoumarin-4-yl)acetyl; Dpa=N-3-(2,4-dinitrophenyl)-L-a,β-diaminopropionyl].
A method for studying activation of the NFAT pathway is by chemically activating the pathway using PMA with Ionomycin (Lyakh et al., Expression of NFAT-Family proteins in normal human T cells, MOLECULAR AND CELLULAR BIOLOGY, Vol. 17, No. 5, May 1997, p. 2475-2484; Rao et al., Transcription factors of the NFAT family-Regulation and function, Annu. Rev. Immunol. 1997. 15:707-47; Macian, NFAT proteins-Key regulators of T-cell development and function, Nature Reviews Immunology, Vol. 5, pp 472-484 June (2005)). It has been demonstrated that PMA and Ionomycin induce expression of NFAT proteins. The above-cited references show a scheme of the regulation of NFAT activation. Ionomycin increases calcium which activates the Calcineurin/Calmodulin complex. Calcineurin/Calmodulin dephosphorylate NFAT, which causes NFATs, especially NFATc1, to be translocated to the nucleus where it binds to DNA to stimulate transcription of target genes. NFATc1 is one of the first NFAT proteins to be translocated to the nucleus upon T cell activation and it is only there transiently before it exits the nucleus. Therefore, PMA plus Ionomycin activation of cells we transfected or transduced with NFAT inducible cleavage enzymes is physiologically relevant and mimics in vivo T cell activation turning on expression of the NFAT inducible cleavage enzymes described herein.
The HEK293T cell line (human embryonic kidney cell), originally referred as 293tsA1609neo, is a highly transfectable derivative of human embryonic kidney 293 cells, and contains the SV40 T-antigen. This cell line is competent to replicate vectors carrying the SV40 region of replication. It gives high titers when used to produce retroviruses. It has been widely used for retroviral production, gene expression and protein production. HEK293T cells were used in some of the early experiments, before the plasmids were inserted into lenti viral vectors and transduced into human T cells.
A plasmid was constructed then transfected into HEK293T cells, wherein the gene for MMP9 catalytic domain was inserted downstream of either 3 or 4 NFAT response elements. The NFAT pathway was activated by the addition of PMA at 10 ng/mL and Ionomycin at either luM or 2 uM. Lysate from cells transfected with the plasmid containing 3 or 4 repeats of a NFAT Response element, or the conditioned media from the cells, were assayed for the presence of MMP9 in a Western blot assay. As can be seen in
We also tested whether the native leader sequence that is in front of the MMP9 gene is essential or if it could be replaced by other leader sequences that might increase its expression or secretion from the cells. These next experiments showed that the native MMP9 leader sequence can be replaced with other leader sequences.
To design a construct that will have cleavage enzyme expression induced by proteins that are expressed or are translocated to the nucleus only after T cell activation, it is possible to have the enzyme gene downstream of response elements or downstream of the promoter of that cleavage enzyme. Another plasmid was made in which the gene for an MMP9 catalytic domain was inserted downstream from a portion of the promoter of NFATc1. The experiments shown in
We next tested whether or not the NFAT-inducible MMP9 would work in human T cells and if it would specifically be expressed and secreted after T cell activation. To test this, the construct having 4 repeats of the NFAT response element were incorporated into a lenti viral vector. Human T cells were transduced with either an NFAT-inducible MMP9 alone, a CAR44 alone or both CAR44 and an NFAT-inducible MMP9. In some cases, the transduced T cells were activated by incubating them with beads coated with anti-CD3 and anti-CD28, which are known to activate T cells. In other cases, the transduced T cells were activated by co-culturing them with beads presenting the synthetic MUC1* peptide or by co-culturing with MUC1* positive cancer cells such as HCT-MUC1* cells.
In one aspect of the invention, a person diagnosed with cancer or at risk of developing cancer is administered a sufficient amount of an immune cell transduced with both a CAR and a cleavage enzyme. In another aspect of the invention, a person diagnosed with cancer or at risk of developing cancer is administered a sufficient amount of an immune cell transduced with both a CAR and a cleavage enzyme, wherein the cleavage enzyme is on an inducible promoter that is activated by proteins that are expressed when the immune cell becomes activated. In another aspect of the invention, a person diagnosed with cancer or at risk of developing cancer is administered a sufficient amount of an immune cell transduced with both a CAR and a cleavage enzyme, wherein the cleavage enzyme is on an inducible promoter that is activated by one or more NFAT. In one case the NFAT is NFATc1. In another aspect, the NFAT is NFATc3. In another aspect, the NFAT is NFATc2. In any of the instances above, the extra cellular domain of the CAR comprises a fragment of an anti-MUC1* antibody. In one aspect, the anti-MUC1* antibody is MNC2scFv or a humanized form of MNC2scFv. In another aspect, the anti-MUC1* antibody is MNE6scFv or a humanized form of MNE6scFv. In any of the instances above, the immune cell can be a T cell, an NK cell, a mast cell, or a dendritic cell.
It is not intended that the present invention be limited to one or two specific methods of having expression of a cleavage enzyme induced by an activated T cell. We have demonstrated specific expression of a cleavage enzyme only upon T cell activation by constructing a plasmid with the cleavage enzyme gene downstream of an NFAT promoter sequence or downstream of one or more repeats of NFAT response elements. In another aspect of the invention, expression of the cleavage enzyme is induced by constructing a plasmid where the cleavage enzyme gene is inserted downstream of an IL-2 promoter sequence or downstream of an IL-2 response element, then inserting the plasmid into an immune cell. In another aspect of the invention, expression of the cleavage enzyme is induced by constructing a plasmid where the cleavage enzyme gene is inserted downstream of a Calcineurin promoter sequence or downstream of a Calcineurin response element, then inserting the plasmid into an immune cell and then administering to a patient for the treatment or prevention of cancers. There are also drug-inducible plasmids that can be used to induce expression of the cleavage enzyme or used to stop expression induced by an element of an activated T cell. These drug inducible systems may include tetracycline-inducible systems, Tet-on, Tet-off, tetracycline response elements, doxycycline, tamoxifen inducible systems, ecdysone inducible systems and the like.
It is not intended that the present invention be limited to one or two specific promoters used in the plasmids encoding the CARs or inducible cleavage enzymes. As is known by those skilled in the art, many promoters can be interchanged including SV40, PGK1, Ubc, CAG, TRE, UAS, Ac5, polyhedron, CaMKIIa, GAL1, GAL10, TEF1, GDS, ADH1, CaMV35S, Ubi, H1 and U6. Another solution to the problem of steric hindrance of CAR T cell access, caused by bulky cell surface proteins such as MUC1-FL, is to increase the length of the linker region of the CAR that is expressed by the T cell. In standard design CARs, the length of the extracellular linker region between the transmembrane portion and the antibody fragment is about 45-50 amino acids in length. We made long-arm CARs where the length of the extracellular linker is extended from about 50 amino acids to 217-290 amino acids. Co-culture assays show that CARs with longer extracellular linkers have improved access to the tumor-associated antigen on the target cancer cells. A cartoon of this strategy is shown in
Published reports of CARs generally use a linker between the transmembrane domain and the antibody fragment, scFv, that is 45-50 amino acids in length and is often the sequence of the extracellular domain of CD8. CAR 44 is an anti-MUC1* CAR whose linker is derived from CD8 extracellular domain and is 45 amino acids in length. To demonstrate that long-arm CARs enable the T cell greater access to tumor associated antigens near the cell surface, we made a series of CARS wherein the anti-MUC1* antibody fragment was MNC2 scFv (SEQ ID NO:655) which was connected to the transmembrane domain via a panel of linkers of variable length and flexibility, wherein the transmembrane domain was that of CD8 (SEQ ID NO:657), followed by co-stimulatory domain 4-1BB (SEQ ID NO:659) then CD3-zeta (SEQ ID NO:661). A panel of linkers were incorporated into this model CAR. An IgG1 Fc domain which is 232 amino acids in length (SEQ ID NO:663) was used as a linker for an MNC2 CAR (SEQ ID NO:665). An IgD Fc domain which is 290 amino acids in length (SEQ ID NO:667) was used as a linker for an MNC2 CAR (SEQ ID NO:669). An IgG1 hingeless Fc domain linker which is 217 amino acids in length (SEQ ID NO:671) was used as a linker for an MNC2 CAR (SEQ ID NO:673). An IgD hingeless Fc domain linker which is 275 amino acids in length (SEQ ID NO:675) was used as a linker for an MNC2 CAR (SEQ ID NO:677). An IgD linker which is 58 amino acids in length (SEQ ID NO:679) was used as a linker for an MNC2 CAR (SEQ ID NO:681). An X4 linker which is 43 amino acids in length (SEQ ID NO:683) was used as a linker for an MNC2 CAR (SEQ ID NO:685).
These CARs with variable length linkers between the scFv and the transmembrane domain are: CAR15: huE6-IgD-CD8-41BB-3z (SEQ ID NO: 324); CAR16: muE6-IgD-CD8-41BB-3z (SEQ ID NO: 823); CAR17: muC2IgD-CD8-41BB-3z (SEQ ID NO: 825); CAR18: huE6-Fc-CD8-41BB-3z (SEQ ID NO: 311); CAR19: huE6-FcH-CD8-41BB-3z (SEQ ID NO: 316); CAR20: huE6-X4-CD8-41BB-3z (SEQ ID NO: 330); CAR33: huE6-IgD-CD441BB-3z (SEQ ID NO: 327); CAR34: huE6-Fc-CD441BB-3z (SEQ ID NO: 319); CAR35: huE6-FcH-CD441BB-3z (SEQ ID NO: 321); CAR36: huE6-X4-CD441BB-3z (SEQ ID NO: 334); CAR39: muE6-CD28-CD28-CD28-3z (SEQ ID NO: 827); CAR40: muC2-CD28-CD28-CD28-3z (SEQ ID NO: 829); CAR53: huC2-Fc-CD8-41BB-3z (SEQ ID NO: 665 and 733); CAR54: huC2-IgD+Fc-CD8-41BB-3z (SEQ ID NO: 669 and 735); CAR55: huC2-FcH-CD8-41BB-3z (SEQ ID NO: 673 and 737); CAR56: huC2-IgD+FcH-CD8-41BB-3z (SEQ ID NO: 677 and 739); CAR57: huC2-IgD-CD8-41BB-3z (SEQ ID NO: 681 and 741); CAR58: huC2-X4-CD8-41BB-3z (SEQ ID NO: 685 and 743); CAR63: huE6-IgD+Fc-CD8-41BB-3z (SEQ ID NO: 771); CAR64: huE6-IgD+FcH-CD8-41BB-3z (SEQ ID NO: 773); CAR42: hu a-CD19-IgD-CD8-41BB-3z (SEQ ID NO: 831). Additional details regarding these long linker CARs are shown in Table 1. Table 2 shows experimental activity of some of the CARs when transduced into human T cells and co-cultured with cancer cells.
In co-culture experiments, anti-MUC1* CARs with extracellular domain linkers of varying lengths were tested for their ability to specifically kill target MUC1/MUC1* positive cancer cells. xCELLigence scans shown in
Table 2 shows cytokine release data for human T cells transfected with some of the long linker CARs.
We note that “long-arm” CARs that have increased efficacy against solid tumor cancers can be guided by any antibody fragment that recognizes a tumor associated antigen, including MNE6 scFv, MNC2-scFv and other anti-MUC1* antibody fragments. Similarly, the transmembrane portion of the long-arm CARs can be derived from CD8, CD4 or other transmembrane domain. The intracellular tail of the CAR can be comprised of CD3-zeta and any other co-stimulatory domains or combinations thereof including CD28, 4-1BB, and OX40.
In another aspect, the invention is directed to a composition that includes at least two different plasmids transfected into the same immune cell, wherein the first encodes a CAR comprising an antibody fragment, scFv, or peptide that binds to a tumor antigen and the other encodes a gene that is not a CAR, wherein the gene that is not a CAR is expressed from an inducible promoter that is activated by elements of an activated immune cell. In one aspect, the immune cell is a T cell or an NK cell. In one aspect the CAR comprises an antibody fragment, scFv or peptide that binds to the extra cellular domain of MUC1*. In one aspect the CAR comprises an scFv derived from MNC2, MNE6, MNC3 or MNC8. In one aspect the non-CAR species is a cleavage enzyme. In one aspect the cleavage enzyme is MMP2, MMP3, MMP9, MMP13, MMP14, MMP16, ADAM10, ADAM17, ADAM28 or catalytically active fragments thereof. In another aspect the non-CAR species is a cytokine. In one aspect, the Cytokine is IL-7. In one aspect the cytokine is IL-15. In one aspect the cytokine is IL-12. In one aspect the cytokine is IL-18. In another aspect the cytokine is IL-7 and IL-15. In one case expression of the non-CAR species is induced by elements of an activated immune cell. In one aspect the element of an activated immune cell is an NFAT. In one aspect the NFAT is NFATc1, NFATc3 or NFATc2. Cytokines IL-7, IL-15, IL-12 and IL-18 are known to promote T cell persistence. In one aspect of the invention an immune cell described above is administered to a patient for the treatment or prevention of cancer. In one aspect of the invention, the cancer is a MUC1 positive cancer or a MUC1* positive cancer.
In another aspect, the invention is directed to a composition that includes at least two different plasmids transfected into the same immune cell, wherein the first encodes a CAR comprising an antibody fragment, scFv or peptide that binds to the extra cellular domain of an antigen on the surface of a B cell and the other encodes a gene that is not a CAR, wherein the gene that is not a CAR is expressed from an inducible promoter that is activated by elements of an activated immune cell. In one aspect, the immune cell is a T cell or an NK cell. In one aspect the CAR comprises an antibody fragment, scFv or peptide that binds to CD19. In one aspect the CAR comprises sequences derived from SEQ ID NO:830-831. In another aspect the antibody fragment, scFv or peptide binds to a surface antigen of a B cell or a B cell prescursor, or binds to CD19, CD20, CD22, BCMA, CD30, CD138, CD123, CD33 or LeY antigen. In one aspect the non-CAR species is a cleavage enzyme. In another aspect the non-CAR species is a cytokine. In one aspect, the Cytokine is IL-7. In one aspect the cytokine is IL-15. In another aspect the cytokine is IL-7 and IL-15. In one case expression of the non-CAR species is induced by elements of an activated immune cell. In one aspect the element of an activated immune cell is an NFAT. In one aspect the NFAT is NFATc1, NFATc3 or NFATc2. that is not a CAR, wherein the gene that is not a CAR is expressed from an inducible promoter wherein expression is induced by elements of an activated immune cell. In one aspect the immune cell transfected or transduced with the composition is administered to a patient for the treatment or prevention of cancer. In one case the cancer is a leukemia, lymphoma or blood cancer.
It is not intended for the invention to be limited by a specific method or technology for inserting the gene or plasmid comprising a sequence encoding a CAR or activated T cell inducible protein or peptide there encoded. For example, the gene encoding the CARs and activated T cell induced genes described herein can be virally transduced into an immune cell using viruses, which may or may not result in the CAR gene being integrated into the genome of the recipient cell. Virus delivery systems and viral vectors include but are not limited to retroviruses, including gamma-retroviruses, lentivirus, adenoviruses, adeno-associated viruses, baculoviruses, poxvirus, herpes simplex viruses, oncolytic viruses, HF10, T-Vec and the like. In addition to viral transduction, CARs and activated T cell induced genes described herein can be directly spliced into the genome of the recipient cell using methods such as CRISPR technology, CRISPR-Cas9 and -CPF1, TALEN, Sleeping Beauty transposon system, and SB 100×.
Bulky cell surface proteins such as MUC1-FL can also cause a steric hindrance problem for BiTEs. A BiTE is a two-headed bi-specific antibody wherein one head binds to a T cell and the other head binds to a tumor-associated antigen. In this way, the BiTE links together the T cell and the tumor cells. The antibody that binds to the T cell should be an antibody that activates the T cell, such as an antibody against CD3 such as OKT3 scFv (SEQ ID NO:687) or CD28. To solve the steric hindrance problem, the linker between the T cell specific antibody and the tumor specific antibody is lengthened. Examples of BiTEs with extended linkers Anti-CD3-linker-anti-MUC1*, are shown as SEQ ID NOS:689, 691, 693, 695, 697, and 699.
In another aspect of the invention, an anti-MUC1* single chain molecule is fused to a cleavage enzyme or a catalytically active fragment of a cleavage enzyme. In one aspect of the invention, the cleavage enzyme is MMP9 (SEQ ID NO:701). In another aspect of the invention, the enzyme is a catalytically active fragment of MMP9 (SEQ ID NO:703). In some cases, the antibody fragment of the CAR is chosen for its ability to recognize MUC1* when cleaved by that specific cleavage enzyme. In one embodiment, the cleavage enzyme is MMP9, MMP3, MMP14, MMP2, ADAM17, ADAM TS16, and/or ADAM28. In one embodiment, the antibody or antibody fragment binds to a peptide having the sequence of SEQ ID NO:2 (PSMGFR) GTINVHDVETQFNQYKTEAASRYNLTISDVSVSDVPFPFSAQSGA, PSMGFR N-10, QFNQYKTEAASRYNLTISDVSVSDVPFPFSAQSGA, or PSMGFR N+18 SNIKFRPGSVVVQLTLAFREGTINVHDVETQFNQYKTEAASRYNLTISDVSVSDVPFPFSAQS GA. “PSMGFR N+18” refers to a fragment of MUC1 receptor in which 18 amino acid residues have been added at the N-terminal end of PSMGFR segment within the MUC1 receptor of SEQ ID NO:1. In another embodiment, cleavage enzymes MMP9 and MMP3 are transduced into a T cell that is also transduced with a CAR with an antibody fragment that is a fragment of MNC2.
In many cases it is desirable to have the cleavage enzyme expressed only after an immune cell recognizes the tumor-associated target on a solid tumor. In this way, the cleavage enzyme will not freely move throughout the body, cleaving MUC1, MUC16 or other proteins, wherein their cleavage could actually promote cancer. However, there are cancers that are physically accessible to direct application of chemotherapy agents, CAR T cells and other anti-cancer agents. For example, types of brain cancers, prostate cancer and ovarian cancers have all shown the benefit of direct application of anti-cancer agents into the local vicinity of the cancer. CAR T cells have been injected directly into the brain and/or cerebral spinal fluid of glioblastoma patients. Radiation has been directed to the prostate area for the treatment of prostate cancers, including those that have metastasized. Hot chemo therapy agents have been directly injected into the intraperitoneal cavity for the treatment of ovarian cancers. In these and other cases, where the cancers that are physically accessible to direct application of chemotherapy agents, a cleavage enzyme is administered in the presence or absence of another anti-cancer agent, which could be a CAR T cell, an immune cell engineered to recognize a tumor-associated antigen, a BiTE, an ADC, a biological or a standard chemotherapy agent. Although ovarian cancer can metastasize to anywhere in the body, it usually stays in the abdomen as it spreads to adjacent organs, such as the intestines, liver and stomach. This makes ovarian cancer an ideal test case for improving the effect of anti-cancer agents by administering a cleavage enzyme in combination with other anti-cancer agents, including a platinum-based drug such as carboplatin (Paraplatin) or cisplatin, and/or a taxane such as paclitaxel (Taxol) or docetaxel (Taxotere). Alkeran (Melphalan), Avastin (Bevacizumab), Carboplatin, Clafen (Cyclophosphamide), and Cytoxan have all been approved for the treatment of ovarian cancer. Other treatments that are being tested for the treatment of ovarian cancers include agents that target MUC1, MUC16 and as described herein, MUC1*.
As a demonstration of the efficacy of the addition of a cleavage enzyme, we implanted NOD/SCID/GAMMA mice with human SKOV-3 ovarian cancer cells into the intraperitoneal cavity to mimic ovarian cancer that has spread beyond the ovary. Mice were treated with anti-MUC1* CAR T cells both by intraperitoneal (i.p.) and by intravenous (i.v.) injection.
Other cleavage enzymes can be used in addition to or in place of MMP9. MMP14 for example, has been shown to efficiently cleave MUC1 to MUC1* (
In yet another aspect of the invention, the cancer is an ovarian cancer and either MMP9 or MMP14 is directly injected into the abdominal area along with an anti-cancer agent, which can be a chemotherapy agent, a biological, an anti-MUC1* CAR T or an anti-MUC16 CAR T.
In addition to local administration of the cleavage enzyme, +iv administration alone or secreted from an immune cell, which may be a CAR T cell, which further may be expressed off of an inducible promoter is contemplated.
HEK293 or HEK293T cells (ATCC) were used to produce lentivirus. The day prior transfection plates (6 well plate) were coated with poly-D-lysine and cells seeded so that cell density reaches 90-95% at the time of transfection and cultures in a 5% CO2 atmosphere. The next day cells were transfected with Lipofectamine 3000 (life technologies) and Opti-MEM® I Reduced Serum Medium according to the manufacturer instructions (0.75 ug of lentiviral expression vector and 2.25 ug of pPACKH1 packaging mix was used). After 6 h incubation, the media was changed and media containing lentivirus was harvested after 24 and 48 hours. Lentivirus was concentrated with Lenti-X concentrator (Clontech) and titer was calculated using the Lenti-X p@4 Rapid Titer Kit (Clontech). Lentivirus was store at −80 C in single-use aliquots.
Transduction of Immune Cells with Constructs Including CARs
Human T cells, if frozen, were thawed and pre-warmed in 100-200 units IL-2 and TexMACS medium, 20 ml, and pelleted by centrifugation. Cells were resuspended in 10 ml of medium and cultured at 37° C., 5% CO2 at 1×106 cells/ml in complete medium with anti-CD3/anti-CD28 beads (TransAct kit).
After 4 days in culture, cells were counted and 450 ul of cell suspension was placed in single well of a 24-well plate at a density of approximately 1×106 cells/ml. Cells were allowed to settle. 150 ul was carefully removed from the top of each well. To each well was added an appropriate dilution of lentiviral vector, diluted in plain TexMACS medium, along with protamine sulfate to a final concentration of 10 ug/ml, in a 150 ul volume, for a final total volume of 450 ul per well and incubated for 24 hrs. Transduced cells were removed, pelleted by centrifugation, and resuspended in fresh medium, adjusting cell density, not to exceed 1.0×106 cells/ml. Transduced T cells can be expanded and frozen or used directly. Typically transduced T cells are used or frozen between Day 7 and Day 20 post activation with IL-2 and TransAct media.
Human T cells (ALLCELLS) were transduced with anti-MUC1* CAR18, CAR19, CAR44, CAR49, CAR44 and CAR49 or CAR50. The CAR constructs all had a GFP marker so that CAR T cells are green and untransduced T cells (
3. Confocal Imaging of CAR T Cells Giving the “Kiss of Death” to MUC1* Positive Cancer cells.
Human T cells that were transduced with CAR44 were co-cultured for 24 hours with MUC1* positive cancer cells that were stably transfected with GFP (green). All of the cells were stained with DAPI (blue). Granzyme B was stained with a fluorophore. After T cell activation, they express perforin that is thought to make a hole in the target cancer cells. The T cell then injects the cancer cell with granzyme B (yellow) which then induces apoptotic pathways, resulting in cancer cell lysis.
There are many methods for analyzing cytotoxicity by FACS. In this example, human T cells were isolated from whole blood according to standard protocols. The T cells were then separately transduced twice with lenti virus bearing the CAR constructs, wherein the CAR constructs bear a GFP tag. Following 2-3 days of culture in RPMI 10% FBS and IL-2, the cells were stained with F(ab′)2 to label surface expression of MN-E6, MN-C2, MN-C3 and MN-C8. Cells were then sorted by flow cytometry for Fab-positive, GFP-positive cells. That means that the double positive population had a CAR inserted and that the CAR exposed the correct antibody fragment. The CAR T cells were then ready to be mixed with the MUC1* negative control cells or the target MUC1* positive cancer cells.
The target cells were prepared as follows: Harvest target cells and resuspend cells in serum-free medium containing 15 uM of CMTMr dye (Cell Tracker Orange, 5-and-6-4-chloromethyl benzoyl amino tetramethylrhodamine, Thermo Fisher) at 1-1.5×106 cells/mL. Incubate 30 min under growth conditions appropriate to particular cell type. Wash in culture media and transfer stained cells to a new tube and incubate the cells 60 min in media. Wash 2 more times in culture media to get rid of all excess dye. Set up the assay in 24 well plates with 0.5 ml media total volume. Resuspend the target cells (and control target cells) so that there are always 20,000 cells per well (20,000 cells/250 ul). Plate 250ul in each well. Add 250ul of the T cells so that the ratio of T cell: target cells=20:1, 10:1, 5:1 or 1:1. Analyse cells after 24 h and 72 h. For suspension target cells, take off the 0.5 ml media from the well and place in tube, wash the well with 0.5 ml media or PBS. For adherent target cells, take off the 0.5 ml media from the well and place in tube, wash the well with 0.5 ml PBS. Add the PBS to the same tube and add 120ul trypsin to the well. Incubate for 4 min then add 0.5 ml media to neutralize trypsin and place that in the tube as well. Spin cells and resuspend pellet in 100ul FACS buffer. Spin cells again. Resuspend cells in 100ul buffer+5ul anti-CD3 antibody, for 30 min on ice (to stain T cells). After 30 min, wash stained cells 2× with FACS buffer and resuspend in 250ul buffer. Run the cells through the filter cap of the FACS tube. 10 min prior to analysis, add 10ul 7AAD dye to each tube and analyze with Fortessa under the Cytotoxicity template.
IFN-γ secretion in media was measured using a human IFN-γ ELISA kit (Biolegend). Plates were coated with an anti-IFN-γ antibody (capture antibody, 1× in coating buffer). After overnight incubation at 4° C., the plate was washed 4 times with PBS-T and blocking solution was added to block remaining binding site on the well. After 1 h at RT (shaking at 500 rpm) the plate was washed 4 times with PBS-T and conditioned media (CM) and IFN-γ standard, was added. After 2 h at RT with shaking, the plate was washed 4 times with PBS-T and detection antibody (1×), was added. After 1 h at RT with shaking, the plate was washed 4 times with PBS-T and Avidin-HRP (1×) was added. After 30 min at RT with shaking, the plate was washed 5 times with PBS-T (soak 1 min each wash) and TMB substrate solution was added. The reaction was stopped after 20 min by adding the stop solution and absorbance was read at 450 nm (minus absorbance at 570 nm) within 15 min of stopping.
6. Analysis of CAR T Cell Induced Killing of MUC1* Positive Cancer Cells by xCELLigence
In addition to FACS analysis, many researchers now use an xCELLigence instrument to measure CAR T killing of cancer cells. The xCELLigence instrument uses electrode arrays upon which cancer cells are plated. The adherent cancer cells insulate the electrode and so cause an increase in impedance as they grow. Conversely, T cells are not adherent and remain in suspension so do not contribute to insulation of the electrode which would increase impedance. However, if the T cells or CAR T cells kill the cancer cells on the electrode plate, the cancer cells ball up and float off as they die, which causes the impedance to decrease. The xCELLigence instrument measures impedance as a function of time, which is correlated to cancer cell killing. In addition, the electrode plates also have a viewing window. When CAR T cells effectively kill the adsorbed target cancer cells, there is a decrease in impedance but also one can see that there are no cancer cells left on the plate surface.
In most of the XCELLigence experiments, 5,000 cancer cells were plated per well of a 96-well electrode array plate. Cells were allowed to adhere and grow for 24 hours. CAR T cells were then added at an Effector to Target ratio (E:T) of 0.5:1, 1:1, 2:1, 5:1, 10:1 and sometimes 20:1. The E:T ratio assumes 100% transduction of the CAR into the T cells, when the actual transduction efficiency is 40%.
The xCELLigence instrument records impedance as a function of time and experiments can go on for up to 7 days.
Female NOD/SCID/GAMMA (NSG) mice between 8-12 weeks of age were implanted with 500,000 human cancer cells, wherein the cancer cells had previously been stably transfected with Luciferase. Mice bearing Luciferase positive cells can be injected with the enzyme's substrate Luciferin just prior to imaging, which makes the cancer cells fluoresce. The cancer cells are imaged in live mice within 10-15 minutes after injection with Luciferin on an IVIS instrument. The readout is flux or photons per second. Tumors were allowed to engraft until tumors were clearly visible by IVIS.
HCT-MUC1-41TR also known as HCT-MUC1-18 cells that stably express MUC1 full length were seeded in 6 channel u-slide VI 0.4 (Ibidi, WI) in DMEM+10% FCS. 48 h later, cells were washed with 120 uL of PBS pH 7.4 and MMP9 catalytic domain (Enzo Life Sciences, NY), diluted in serum free medium (DMEM), was added at different concentrations (40 uL at 0, 12.5, 25, 50 and 100 ng/mL). After 1 h at 37° C. in a CO2 incubator, cells were washed twice with 120 uL of cold PBS pH 7.4 and fixed for 8 min in 4% PFA (30 uL). Cells were washed 3 times with cold PBS pH 7.4 and blocked with a 5% BSA solution in PBS pH 7.4 (40 uL) for 30 min at 4° C. (with shaking). After washing cells with cold PBS pH 7.4 (1×), cells were incubated overnight at 4° C. (with shaking) with 125 ug/mL of MNC2 diluted in PBS pH 7.4 (100 uL). Next day, cells were washed 3× with 120 uL of PBS pH 7.4 and incubated 2 h at 4° C. (with shaking) with goat anti-mouse IgG PE (Biolegend, CA) diluted in PBS pH 7.4 (100 uL, 1:200). After incubation, cells were washed 1× with 120 uL of PBS pH 7.4 and 2× with 120 uL of PBS pH 7.4+2.5 uM Hoechst 33342. Finally, cells were mounted with Ibidi mounting media (Ibidi, WI). Results show that addition of MMP9 induced cleavage of full-length MUC1 to a MUC1* form that was recognized by anti-MUC1* monoclonal antibody MNC2 (
Vectors containing either 4 repeats of a NFAT response element or the NFATc1 promoter followed by the MMP9 catalytic domain were transiently transfected into HEK293TN cells (System Biosciences, CA) with Lipofectamine 3000 (ThermoFisher Scientific, MA) according the manufacturer manual. After 24-30 h, media was changed to DMEM+1% FBS+10 ng/mL PMA (Cayman Chemical, MI) and Ionomycin (1-6 uM, Cayman Chemical, MI). Media and cells were collected after 18 h incubation for analysis.
Expression and secretion of MMP9 was confirmed by Western blot analysis of the cell lysates and conditioned media according to the following protocols. Cells were lysed for 20 min on ice with lysis buffer (50 mM Tris, 150 mM NaCl and 1% Triton X100). For Western blot, 100 ug of protein were separated by gel electrophoresis (4-15% Mini-PROTEAN® TGX™ Precast Protein Gels, BioRad, CA) followed by transfer to PVDF membrane (BioRad, CA). The membrane was briefly rinsed with PBS-T and then blocked for 1 h at room temperature with a solution of 3% non-fat milk (BioRad, CA). For Flag tagged protein, the membrane was quickly washed and incubated with a rabbit anti-DYKDDDDK epitope Tag antibody (Biolegend, CA) was diluted in 1% non-fat milk (1:2000) for 2 h at room temperature. For His tagged protein, the membrane was quickly washed and incubated with a rabbit anti-6×His tag antibody HRP (Abcam, MA) diluted in 1% non-fat milk (1:10000) for 1 h at room temperature. For Flag tagged protein, the membrane was then washed 3 times for 10 min with PBS-T and incubated with goat anti-Rabbit HRP antibody diluted in 1% non-fat milk (1:2500) for 1 h at room temperature. For His tagged protein and after the secondary antibody incubation for the Flag tagged protein, the membrane was processed after being washed 3 times for 10 min with PBS-T using Clarity™ Western ECL Substrate (BioRad, CA).
In some cases, the protein was first immunoprecipitated before analysis. Flag tagged MMP9 catalytic domain was immunoprecipitated from conditioned media (˜2 mL) using an anti-DYKDDDDK Tag (L5) affinity gel (Biolegend, CA) according to manufacturer manual. Pull down proteins were used for Western blot analysis or cleavage assay.
Results show that T cells transduced with NFAT-inducible MMP9 express MMP9 when they are activated. T cells transduced with both CAR44 and NFAT-inducible MMP9 are specifically activated when they are co-cultured with beads or cells presenting or expressing MUC1* (
OMNIMMP fluorogenic substrate (Enzo life sciences, NY) was diluted to 20 uM in assay buffer (50 mM Tris pH 7.5, 300 mM NaCl, 1 mM CaCl2, 5 uM Zncl2, 0.1% Brj-35 and 15% glycerol) and kept on ice and protected from light until used. Peptide can also be diluted in PBS pH 7.4 or culture medium. Cell lysate was diluted to 0.4 mg/mL is assay buffer (or PBS pH 7.4 or culture medium). For the assay, 50 uL of recombinant MMP9 catalytic domain (1-2 ug/mL in assay buffer, PBS pH 7.4 or culture medium), 50 uL of diluted cell lysate, 50 uL of conditioned media or 50 uL of pulled down protein was added to wells of a 96 well plate compatible with fluorometer. Just before starting the assay, 50 uL of diluted peptide was added to each well and quickly mixed (final peptide concentration is 10 uM). Fluorescence was recorded every 10 min for about 6 h at 37° C. (Ex.: 328 nm, Em.: 393 nm).
Two sequences were synthesized (pNFAT-MMP9cat-1 and pNFAT-MMP9cat-2, (SEQ ID NO:784 and SEQ ID NO:785). The lentivector pGreenFire1-4×NFAT (System Biosciences, CA) was digested with SpeI and KpnI restriction enzymes (New England Biolabs). The purified fragment and the 2 synthesized sequences were assembled using the Gibson assembly cloning kit (New England Biolab). The resulting constructs (pGreenFire1-4×NFAT-MMP9cat) contains 4 repeats of a NFAT response element followed by a minimum promoter (mCMV) and the MMP9 catalytic domain with its native leader sequence.
Cloning of NFAT response element in pGL4-14[luc2/Hygro]:
The 4×NFAT domain was amplified from the lentivector pGreenFire1-4×NFAT by polymerase chain reaction (PCR) using the following primer: 5′-tagatggtaccaagaggaaaatttgtttcatacag-3′ (SEQ ID NO: 786) and 5′-tagataagcttgctggatcggtcccggtgtc-3′ (SEQ ID NO: 787). After digestion with KpnI and HindIII restriction enzymes (New England Biolabs), the purified fragment was cloned into the promoter-less vector pGL4-14[luc2/Hygro] (Promega) digested with the same restriction enzymes to create the construct pGL4-14-4×NFAT.
Cloning of MMP9 Catalytic Domain into pGL4-14-4×NFAT:
A fragment containing a minimum promoter (mCMV) followed by MMP9 native leader sequence and MMP9 catalytic domain was amplified from the lentivector pGreenFire1-4×NFAT-MMP9cat by polymerase chain reaction (PCR) using the following primer: 5′-tcatacagaaggcgttactagttaggcgtgtacggtgg-3′ (SEQ ID NO:788) and 5′-acagtaccggattgccaagcttttatcacttatcgtcgtcatccttg-3′ (SEQ ID NO:789). pGL4-14-4×NFAT was digested with SpeI and HindIII restriction enzymes (New England Biolabs). The purified PCR fragment and digested pGL4-14-4×NFAT were assembled using the Gibson assembly cloning kit (New England Biolab) to create the construct pGL4-14-4×NFAT-MMP9cat.
Cloning of MMP9 Catalytic Domain into pSECTag2:
MMP9 catalytic domain without its native leader sequence was amplified from the lentivector pGreenFire1-4×NFAT-MMP9cat by polymerase chain reaction (PCR) using the following primer: 5′-aagttggtaccgttccaaacctttgagggcgacc-3′ (SEQ ID NO:790) and 5′-aagttctcgagcaggttcagggcgaggaccatag-3′ (SEQ ID NO:791). After digestion with KpnI and XhoI restriction enzymes (New England Biolabs), the purified fragment was cloned into the vector pSECTag2 A (ThermoFisher Scientific) digested with the same restriction enzymes to create the construct pSECTag2 MMP9 cat His. In this construct MMP9 catalytic domain will downstream if the IgK leader sequence.
Cloning of MMP9 Catalytic Domain with IgK Leader Sequence into pGL4-14-4×NFAT:
MMP9 catalytic domain with its native leader sequence was amplified from the pGL4-14-4×NFAT-MMP9cat by polymerase chain reaction (PCR) using the following primer: 5′-attgactcgagctctcgacattcgtttctagagc-3′ (SEQ ID NO:792) and 5′-attgaaagcttttatcacttategtcgtcatccttg-3′ (SEQ ID NO:793). After digestion with XhoI and HindIII restriction enzymes (New England Biolabs), the purified fragment was cloned into the vector pGL4-14[luc2/Hygro] (Promega) digested with the same restriction enzymes to create the construct pGL4-14 MMP9cat XH.
A fragment containing 4×NFAT response elements followed by the minimum promoter (mCMV) was amplified from pGL4-14-4×NFAT-MMP9cat by polymerase chain reaction (PCR) using the following primer: 5′-tagcaaaataggctgtccc-3′ (SEQ ID NO:794) and 5′-attgactcgaggctggateggtcccggtgtc-3′ (SEQ ID NO:795). After digestion with KpnI and XhoI restriction enzymes (New England Biolabs), the purified fragment was cloned into the vector pGL4-14 MMP9cat XH digested with the same restriction enzymes to create the construct pGL4-14 4×NFAT-MMP9cat KXH
A fragment containing the IgK leader sequence followed by MMP9 catalytic domain was amplified from pSECTag2 MMP9 cat by polymerase chain reaction (PCR) using the following primer: 5′-aagacaccgggaccgatccagcctcgagagacccaagctggctagccacc-3′ (SEQ ID NO:796) and 5′-ttaccaacagtaccggattgccaagcttttatcacttatcgtcgtcatcc-3′ (SEQ ID NO:797). pGL4-14 4×NFAT-MMP9cat KXH was digested with XhoI and HindIII restriction enzymes (New England Biolabs). The purified PCR fragment and digested pGL4-14 4×NFAT-MMP9cat KXH were assembled using the Gibson assembly cloning kit (New England Biolab) to create the construct pGL4-14-4×NFAT-IgK MMP9cat.
Cloning of MMP9 Catalytic Domain into pEZX-PG02.1 Downstream of NFATc1 Promoter:
MMP9 catalytic domain with its native leader sequence was amplified from the lentivector pGreenFire1-4×NFAT-MMP9cat by polymerase chain reaction (PCR) using the following primer: 5′-attgaaagcttctctcgacattcgtttctagagc-3′ (SEQ ID NO:798) and 5′-attgagagctcttatcacttatcgtcgtcatc-3′ (SEQ ID NO:799). After digestion with HindIII and SacI restriction enzymes (New England Biolabs), the purified fragment was cloned into the vector pEZX-PG02.1 downstream of the NFACTcl promoter (GeneCopoeia, MD) to create the construct pEZX-NFATc1-MMP9cat.
Modification of pEZX-NFATc1-MMP9cat:
pEZX-NFATc1-MMP9cat was modified to introduce SpeI and KpnI restriction site 5′ of the NFATc1 promoter and NheI and EcoRV restriction site 3′ of MMP9 catalytic domain. Two gBLOCKs were synthesized by our request by IDT, IA. (NFAT modif 1 and NFAT modif 2, SEQ ID NO:800 and SEQ ID NO:801). The pEZX-NFATc1-MMP9cat vector was digested with NheI, EcoRI, SacI and XhoI restriction enzymes (New England Biolabs). Two fragments were purified and assembled with the two synthesized gBLOCKS using the Gibson assembly cloning kit (New England Biolab).
Cloning of NFATc1 Promoter/MMP9 Catalytic Domain into Lentivector pCDH-CMV-MCS-EF1α-Hygro:
Modified pEZX-NFATc1-MMP9cat vector was digested with SpeI and NheI restriction enzymes (New England Biolabs) and the fragment containing NFATc1 promoter followed by MMP9 catalytic domain was purified and cloned into the lentivector pCDH-CMV-MCS-EFla-Hygro (System Biosciences) digested with the same restriction enzymes.
Cloning of NFAT Response Element/MMP9 Catalytic Domain into Lentivector pCDH-CMV-MCS-EF1α-Hygro:
A fragment containing 4 repeats of a NFAT response element followed by MMP9 catalytic domain with its native leader sequence was amplified from the vector pGL4-14-4×NFAT-MMP9cat by polymerase chain reaction (PCR) using the following primer: 5′-acaaaattcaaaattttatcgatactagttggcctaactggccggtaccaag-3′ (SEQ ID NO:802) and 5′-atccgatttaaattcgaattcgctagcttatcacttatcgtcgtcatcc-3′ (SEQ ID NO:803). The purified PCR fragment and digested pCDH-CMV-MCS-EFla-Hygro (SpeI and NheI) were assembled using the Gibson assembly cloning kit (New England Biolab).
All of the references cited herein are incorporated by reference in their entirety.
As regards the use of nucleotide symbols other than a, g, c, t, they follow the convention set forth in WIPO Standard ST. 25, Appendix 2, Table 1, wherein k represents t or g; n represents a, c, t or g; m represents a or c; r represents a or g; s represents c or g; w represents a or t and y represents c or t.
ggatgacgacgataagtgataa
Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention specifically described herein.
This application is a continuation of U.S. patent application Ser. No. 16/767,357, filed May 27, 2020, now abandoned, which is a national stage entry of International Application No. PCT/US18/62569, filed Nov. 27, 2018, which claims the benefit of U.S. Provisional Application No. 62/591,120, filed Nov. 27, 2017, the contents of which are incorporated herein by reference in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62591120 | Nov 2017 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16767357 | May 2020 | US |
| Child | 18414324 | US |
