Malignant melanoma is a frequent cancer type. The 5-year survival rate of metastatic melanoma is about 15%, which currently available treatment strategies barely improve.
Interleukin-2 (IL-2) is a cytokine able to potently stimulate cytotoxic lymphocytes against metastatic tumours. IL-2 however also stimulates so-called CD25+ CD4+ regulatory T cells (Treg cells) that are crucial for prevention of autoimmune disease. Treg cells can significantly dampen anti-tumour responses by cytotoxic lymphocytes, thus antagonizing the beneficial anti-tumour effects of IL-2. IL-2 can exert toxic adverse effects at doses required to achieve a clinical anti-tumour response.
Standard IL-2 immunotherapy has been used for the immunotherapy of metastatic melanoma and metastatic renal cell carcinoma. While IL-2 given at high doses has shown objective response rates in about 17% and complete regression in about 6-9% of patients, IL-2 given at these doses frequently led to toxic adverse effects.
Previous work by the inventors has provided a human interleukin-2 (hIL-2)-specific monoclonal antibody (mAb) that inhibits binding of hIL-2 to CD25 and potently stimulates cytotoxic cells, but not Treg cells. In subsequent work, the inventors tried to elucidate the potential of this antibody to be further improved by combination with immune modulatory approaches.
The problem underlying the present invention is to improve the existing therapy based on anti-human IL-2 monoclonal antibodies able to recognize and bind a specific epitope of human IL-2, thereby enabling stimulation of cytotoxic T cells, but not of Treg cells. This problem is solved by the subject-matter of the independent claims.
Identity in the context of the present specification is a single quantitative parameter representing the result of a sequence comparison position by position. Methods of sequence comparison are known in the art; the BLAST algorithm available publicly is an example. One example for comparison of amino acid sequences is the BLASTP algorithm that uses default settings such as: Expect threshold: 10; Word size: 3; Max matches in a query range: 0; Matrix: BLOSUM62; Gap Costs: Existence 11, Extension 1; Compositional adjustments: Conditional compositional score matrix adjustment. One such example for comparison of nucleic acid sequences is the BLASTN algorithm that uses the default settings: Expect threshold: 10; Word size: 28; Max matches in a query range: 0; Match/Mismatch Scores: 1.-2; Gap costs: Linear
In the context of the present specification, the term antibody is used in its meaning known in the art of cell biology and immunology; it refers to whole antibodies, any antigen binding fragment or single chains thereof and related or derived constructs. A whole antibody is a glycoprotein comprising at least two heavy (H) chains and two light (L) chains inter-connected by disulfide bonds. Each heavy chain is comprised of a heavy chain variable region (VH) and a heavy chain constant region (CH). The heavy chain constant region is comprised of three domains, CH1, CH2 and CH3. Each light chain is comprised of a light chain variable region (abbreviated herein as VL) and a light chain constant region (CL). The light chain constant region is comprised of one domain, CL. The VH and VL regions can be further subdivided into regions of hypervariability, termed complementarity determining regions (CDR), interspersed with regions that are more conserved, termed framework regions (FR). Each VH and VL is composed of three CDRs and four FRs arranged from amino-terminus to carboxyterminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. The variable regions of the heavy and light chains contain a binding domain that interacts with an antigen. The constant regions of the antibodies may mediate the binding of the immunoglobulin to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component of the classical complement system.
In the context of the present specification, the term antigen binding portion or antigen binding fragment is used in its meaning known in the art of cell biology and immunology; it refers to one or more fragments of an intact antibody that retain the ability to specifically bind to a given antigen (e.g., interleukin-2). Antigen binding functions of an antibody can be performed by fragments of an intact antibody. Examples of binding fragments encompassed within the term antigen binding portion or antigen binding fragment of an antibody include a Fab fragment, a monovalent fragment consisting of the VL, VH, CL and CH domains; a F(ab)2 fragment, a bivalent fragment comprising two Fab fragments linked by a disulfide bridge at the hinge region; an Fd fragment consisting of the VH and CH domains; an Fv fragment consisting of the VL and VH domains of a single arm of an antibody; a single domain antibody (dAb) fragment, which consists of a VH domain or a VL domain; and an isolated complementarity determining region (CDR).
In the context of the present specification, the term chimeric antibody is used in its meaning known in the art of cell biology and immunology; it refers to an antibody molecule in which the constant region, or a portion thereof, is altered, replaced or exchanged so that the antigen binding site (variable region) is linked to a constant region of a different or altered class, effector function and/or species, or an entirely different molecule which confers new properties to the chimeric antibody, e.g., an enzyme, cytokine, toxin, hormone, growth factor, drug, etc. For example, an antibody can be modified by replacing its constant region with a cytokine. Due to the replacement with a cytokine, the chimeric antibody can retain its specificity in recognizing the antigen while having also the function, or part thereof, of the original cytokine molecule.
In the context of the present specification, the term hybridoma is used in its meaning known in the art of cell biology and biochemistry; it refers to a hybrid cell created by fusion of a specific antibody-producing B-cell with a myeloma (B-cell cancer) cell. Hybridoma cells can be grown in tissue culture and produce antibodies of a single specificity (monoclonal antibodies).
In the context of the present specification, the term single-chain variable fragment (scFv) is used in its meaning known in the art of cell biology and biochemistry; it refers to a fusion protein of the variable regions of the heavy (VH) and light chains (VL) of immunoglobulins, connected with a short linker peptide of ten to about 25 amino acids. The scFv retains the specificity of the original immunoglobulin, despite removal of the constant regions and the introduction of the linker.
In the context of the present specification, the term fragment antigen-binding (Fab) is used in its meaning known in the art of cell biology and immunology; it refers to a region on an antibody that binds to antigens. It is composed of one constant and one variable domain of each of the heavy (VH) and light chains (VL) of immunoglobulins. These domains shape the antigen-binding site at the amino terminal end of the monomer.
In the context of the present specification, the term dissociation constant (KD) is used in its meaning known in the art of chemistry and physics; it refers to an equilibrium constant that measures the propensity of a larger object to dissociate reversibly into smaller components, as when a complex falls apart into its component molecules. KD is expressed in molar units [M] and corresponds to the concentration of [Ab] at which the binding sites of [Ag] are half occupied. In other words the concentration of unbound [Ab] equals the concentration of the [AbAg] complex. The dissociation constant can be calculated according to the following formula:
[Ab]: concentration of antibody; [Ag]: concentration of antigen; [AbAg]: concentration of antibody-antigen complex
In the context of the present specification, the terms off-rate (Koff; [1/sec]) and on-rate (Kon; [1/sec*M]) are used in their meaning known in the art of chemistry and physics; they refer to a rate constant that measures the dissociation (Koff) or association (Kon) of an antibody with its target antigen. Koff and Kon can be experimentally determined using methods well established in the art. A method for determining the Koff and Kon of an antibody employs surface plasmon resonance. This is the principle behind biosensor systems such as the Biacore® or the ProteOn® system. They can also be used to determine the dissociation constant KD by using the following formula:
In the context of the present specification, the term humanized antibodies is used in its meaning known in the art of cell biology and biochemistry; it refers to antibodies originally produced by immune cells of a non-human species, whose protein sequences have been modified to increase their similarity to antibody variants produced naturally in humans.
In the context of the present specification, the term no measurable cross-reactivity refers to the lacking capability of an antibody to recognize and bind to orthologous proteins from other species. For example, an antibody directed against human interleukin-2 would have no measurable cross-reactivity to murine interleukin-2 if, under suitable conditions, binding of the antibody to murine interleukin-2 could not be detected with sufficiently sensitive methods such as surface plasmon resonance. One such example of no measurable cross-reactivity is shown in
In the context of the present specification, the term “human interleukin-2” or “hIL-2” refers to the protein designated UniProt ID P60568 (SEQ ID NO 001).
According to a first aspect of the invention, a combination medicament is provided, wherein the combination medicament comprises:
The human interleukin-2 (hIL-2)-specific monoclonal antibody, or antigen binding fragment thereof, is further characterized by at least one of the parameters:
A lack of cross-reactivity with murine IL-2 is advantageous for preclinical studies, which usually involve mouse models, such as the use of mAb*hIL-2 complexes for the treatment of murine tumour models where a cross-reactive anti-IL-2 mAb might bind and seclude endogenous murine IL-2 from endogenous murine Treg cells, thus enhancing the anti-tumour response.
A lack of cross-reactivity with murine IL-2 is also advantageous for preclinical safety and efficacy studies conducted prior to development of a candidate mAb in human patients.
In certain embodiments, the hIL-2 mAb comprises at least one VH and/or VL sequence having an identity of ≥80%, ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97% or ≥98% compared to SEQ ID NOs 019 or SEQ ID NO 020.
In certain embodiments, the variable chain of the hIL-2 mAb comprises an amino acid sequence having an identity of ≥85%, ≥90%, ≥95%, or ≥99% compared to SEQ ID NOs 003, 004, 005 or 006 and the hIL-2 mAb is characterized by a dissociation constant ≤7.5 nmol/L, ≤5 nmol/L, ≤3 nmol/L, ≤2 nmol/L or ≤1.5 nmol/L.
In certain embodiments, the variable chain of the hIL-2 mAb comprises an amino acid sequence having an identity of ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97%, ≥98% or ≥99% compared to SEQ ID NO 005 or 006 and the hIL-2 mAb is characterized by an off-rate ≤1×10−4 s−1, ≤8×10−5 s−1, ≤6×10−5 s−1, ≤4×10−5 s−1, ≤3×10−5 s−1 or ≤2.1×10−5 s−1.
In certain embodiments, the variable chain of the hIL-2 mAb comprises an amino acid sequence having an identity of ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97%, ≥98% or ≥99% compared to SEQ ID NO 005 or 006 and the hIL-2 mAb displays no measurable cross-reactivity to murine IL-2.
In certain embodiments, the hIL-2 mAb or antigen binding fragment thereof binds to a human interleukin-2 (hIL-2) epitope which comprises the amino acids K52, P54, K55, T57, R58, T61, F62, K63, Q94, and K96, and which comprises any one or more of the amino acids N50, N53, N91, L92, A93, and N97.
In certain embodiments, the hIL-2 mAb or antigen binding fragment thereof comprises an antigen recognition surface having epitope recognition characteristics equivalent to an antibody or antigen binding fragment to a specific human interleukin-2 (hIL-2) epitope which comprises the amino acids K52, P54, K55, T57, R58, T61, F62, K63, Q94, and K96 of hIL-2.
In certain embodiments, the hIL-2 mAb or antigen binding fragment thereof comprises an antigen recognition surface having epitope recognition characteristics equivalent to an antibody or antigen binding fragment to a specific human interleukin-2 (hIL-2) epitope which comprises the amino acids K52, P54, K55, T57, R58, T61, F62, K63, Q94, and K96 of hIL-2 and which comprises any one or more of the amino acids N50, N53, N91, L92, A93, and N97.
In certain embodiments, the sequence of the hIL-2 mAb is humanized for administration to human patients to prevent adverse reactions.
In certain embodiments, the hIL-2 mAb is provided as fragment antigen-binding (Fab) or single-chain variable fragment (scFv).
In certain embodiments, the hIL-2 mAb comprises at least one complementarity determining (CDR) sequence having an identity of ≥80%, ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97% or ≥98% compared to SEQ ID NOs 007, 008, 009, 010, 011 or 012.
In certain embodiments, the hIL-2 mAb comprises at least three different complementarity determining (CDR) sequences, each of which is ≥80%, ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97% or ≥98% or even 100% identical to one of SEQ ID NO 007, SEQ ID NO 008, SEQ ID NO 009, SEQ ID NO 010, SEQ ID NO 011 or SEQ ID NO 012.
In certain embodiments, the hIL-2 mAb comprises at least four, five or six different complementarity determining (CDR) sequences, each of which is ≥80%, ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97% or ≥98% or even 100% identical to one of SEQ ID NO 007, SEQ ID NO 008, SEQ ID NO 009, SEQ ID NO 010, SEQ ID NO 011 or SEQ ID NO 012, respectively.
In certain embodiments, the sequence of the hIL-2 mAb is encoded by a nucleic acid molecule having ≥60%, ≥70%, ≥80%, ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97%, ≥98% or ≥99% sequence identity compared to SEQ ID NOs 003 and/or 004.
The skilled person is aware that an antibody molecule is usually composed of two separate amino acid chains, which in turn on the level of mRNA are encoded by two separate nucleic acid molecules, namely one encoding the heavy chain (with constant and variable regions) and one encoding the light chain (with constant and variable regions). Transgene expression of such two amino acid chains encoding the light and heavy chain will commonly be effected from one transgene expression construct (the nucleic acid molecule). The skilled person however will also be able to find a way to express the two amino acid chains constituting the antibody of the present invention from two different nucleic acid molecules, or to join the two amino acid chains by a linker. In the context of the present specification, the expression “the sequence of the hIL-2 mAb is encoded by a nucleic acid molecule that has ≥98% sequence identity compared to SEQ ID NOs 003 (the heavy chain encoding sequence) and 004 (the light chain encoding sequence)” is synonymous to “the sequence of the hIL-2 mAb is encoded by one or two (separate) nucleic acid molecules encoding one or two (separate) amino acid chains that comprise the sequence encoded by SEQ ID NO 3 and the sequence encoded by SEQ ID NO 4, from which the antibody is constituted”.
In certain embodiments, the sequence of the hIL-2 mAb is encoded by a (at least one, in certain embodiments two) nucleic acid molecule(s) comprising one, two, three, four, five or six sequence tracts characterized by a sequence identity value ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97%, ≥98% or ≥99% when compared to a sequence selected from one, two, three, four, five or six sequences of the group SEQ ID NO 013, SEQ ID NO 014, SEQ ID NO 015, SEQ ID NO 016, SEQ ID NO 017 and SEQ ID NO 018. The skilled person is aware that in instances where two, three, four, five or six sequence tracts are comprised in the sequence of the hIL-2 mAb, these sequences may encode CDR sequences comprised on different parts of the antibody amino acid sequence (i.e. the heavy and light chain, respectively).
In certain embodiments, the sequence of the hIL-2 mAb is encoded by a (at least one, in certain embodiments two) nucleic acid molecule(s) having ≥60%, ≥70%, ≥80%, particularly ≥85%, ≥90%, ≥92%, ≥93%, ≥94%, ≥95%, ≥96%, ≥97%, ≥98% or ≥99% sequence identity compared to SEQ ID NOs 021 and/or 022.
In certain embodiments, the combination medicament further comprises human interleukin-2.
According to an alternative aspect of the invention, a combination medicament is provided that contains an IL-2/IL-2mAB component and a checkpoint inhibitor. The IL-2/IL-2mAB component provides the stimulatory effect of IL-2, concomitantly blocking the signals of IL-2 that provide the effect on Treg cells.
In certain embodiments, the combination medicament further comprises human IL-2.
In certain embodiments, the combination medicament comprises
In other words, the fusion protein retains the ability of the antibody to bind and direct human interleukin-2 to stimulate selected immune cells, such as CD8+ T cells and NK cells. The IL-2 portion of the molecule will be essentially the sequence of IL-2, but the skilled person understands that small sequence changes might be tolerated that retain the biological activity of IL-2, particularly its ability to stimulate cytotoxic effector T-cells.
The advantage of using such fusion protein is that human IL-2 will not be able to dissociate from the antibody and that the therapy will be composed of one single product instead of two, facilitating various aspects of manufacture, dosing and regulatory compliance.
In certain embodiments of any of the aspects of the invention provided herein, the hIL-2 mAb or antigen binding fragment thereof binds to a human interleukin-2 (hIL-2) epitope which further comprises the amino acids N50, N53, N91, L92, A93, and N97 of hIL-2.
In certain embodiments of any of the aspects of the invention provided herein, the immune checkpoint inhibitor agent is an antibody specifically binding to CTLA-4, CD80, CD86, PD-1, PD-L1, TIM-3, BTLA, HVEM, LAG3 or galectin 3.
In certain embodiments of any of the aspects of the invention provided herein, the immune checkpoint inhibitor agent is a non-agonistic antibody specifically binding to CTLA-4, CD80, CD86, PD-1, PD-L1, TIM-3, BTLA, HVEM, LAG3 or galectin 3.
In certain embodiments of any of the aspects of the invention provided herein, the immune checkpoint inhibitor agent is an inhibitor of interaction of CTLA-4 with CD80 or CD86.
In certain embodiments of any of the aspects of the invention provided herein, the immune checkpoint inhibitor agent is ipilimumab (Yervoy; CAS No. 477202-00-9). In certain embodiments of any of the aspects of the invention provided herein, the immune checkpoint inhibitor agent is nivolumab (Opdivo; CAS No. 946414-94-4). In certain embodiments of any of the aspects of the invention provided herein, the immune checkpoint inhibitor agent is pembrolizumab (Keytruda; CAS No. 1374853-91-4). In certain embodiments of any of the aspects of the invention provided herein, the immune checkpoint inhibitor agent is atezolizumab (Tecentriq; CAS No. 1380723-44-3).
According to another aspect of the invention, the combination medicament according to any one of the previous aspects or embodiments is provided for use in therapy of cancer.
In certain embodiments of this aspect of the invention, the combination medicament is provided for use in therapy of malignant melanoma, particularly metastatic malignant melanoma. Both, IL-2 immunotherapy and checkpoint inhibitors, such as anti-PD-1/PD-L1 and anti-CTLA-4, have shown to be beneficial in the treatment of metastatic malignant melanoma.
In certain embodiments of this aspect of the invention, the combination medicament is provided for use in therapy of renal cell cancer. IL-2 immunotherapy has been shown to be beneficial in the treatment of renal cell cancer.
In certain embodiments of this aspect of the invention, the combination medicament is provided for use in therapy of lung cancer. In certain embodiments of this aspect of the invention, the combination medicament is provided for use in therapy of bladder cancer.
Lung cancer and bladder cancer have been shown to be responsive to treatment with immune checkpoint inhibitors that prevent PD-1/PD-L1 interaction.
In certain embodiments of this aspect of the invention, the combination medicament is provided for use in therapy of solid cancer with a regular to frequent load of somatic mutations, also termed cancer neoantigens, in particular melanoma, lung cancer, stomach cancer, esophagus cancer, colorectal cancer, bladder cancer, uterus cancer, cervix cancer, liver cancer, head and neck cancer, kidney cancer, breast cancer, and pancreas cancer. Such cancers have been shown to be responsive to treatment with immunotherapy.
In the context of the present specification, a “regular load of somatic mutations” is defined as 1-10 somatic mutations per megabase of coding DNA, corresponding to 15-150 nonsynonymous mutations within expressed genes, and a “frequent load of somatic mutations” is defined as 10-100 somatic mutations per megabase of coding DNA, corresponding to 150-1500 nonsynonymous mutations within expressed genes (Alexandrov et al., Nature. 2013 Aug. 22; 500(7463):415-21; Schumacher and Schreiber, Science. 2015 Apr. 3; 348(6230):69-74).
Wherever alternatives for single separable features such as, for example, a coding sequence or binding epitope are laid out herein as “embodiments”, it is to be understood that such alternatives may be combined freely to form discrete embodiments of the invention disclosed herein.
The invention is further illustrated by the following items, examples and figures, from which further embodiments and advantages can be drawn. These examples are meant to illustrate the invention but not to limit its scope.
Human Interleukin-2 Specific Antibody
Until now, no monoclonal antibodies (mAbs) suitable for the disclosed invention have been available. The anti-human IL-2 mAbs disclosed herein allow crucial steps towards the use and commercialization of this technology in clinical applications:
The inventors have generated and characterized specific anti-human IL-2 mAbs that are able to bind human IL-2 and, when tested in mice, are able to exert specific and potent stimulation of cytotoxic lymphocytes, including CD8+ T cells and natural killer (NK) cells.
The inventors have developed specific screening assays that allow detection of specific anti-human IL-2 antibodies (so-called “binders”) in the serum of immunized animals and in the supernatant of the B cell clones obtained after B cell hybridoma fusion. In a second step it was discriminated between standard binders and those targeting a presumed specific epitope of the human IL-2 molecule. One example of such an in vitro enzyme-linked immunosorbent assay (ELISA) performed with different B cell clones, is shown in
After the in vitro screening of the anti-human IL-2 mAbs, these mAbs were characterised in vivo. To this end and in order to obtain sufficient amounts of mAbs, the mAbs were concentrated from the supernatant of the hybridomas, the amount was estimated using an ELISA and finally the anti-human IL-2 mAbs was tested in mice. The results obtained on proliferation and expansion of CD8+ T cells and NK cells is shown in
In order to characterize the binding properties of the anti-human IL-2 mAbs the binding to human interleukin-2 was tested with surface plasmon resonance binding assays. The commercially available anti-human IL-2 mAb MAB602 was measured as a comparison. In
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Combination Medicament
Mice
3-month-old female C57Bl/6J mice were purchased (Charles River Laboratories). No statistical methods were used to predetermine sample size. For all experiments presented in this study, the sample size was large enough to measure the effect size. The experiments were not randomized and the investigators were not blinded to allocation during experiments and outcome assessment. Mouse colonies were maintained in certified animal facilities in accordance with Swiss guidelines. All animal experiments were approved by the veterinary authorities of Canton of Zurich, Switzerland, and were performed in accordance with Swiss law and the GlaxoSmithKline policy on the Care, Welfare, and Treatment of Animals. Pre-established exclusion criteria were based on the Canton of Zurich veterinary authority's guidelines and included substantial weight loss of >15% of initial body weight. During the study period most of the animals appeared to be in good health.
Cell Cultures
The murine B16-F10 melanoma cell line was purchased (ATCC). Cells were cultured in growth medium, which was RPMI 1640 (42401, Life Technologies) supplemented with 10% FCS (16140, Life Technologies), 4 mM L-Glutamine (25030, Life Technologies), Penicillin-Streptomycin (15070, Life Technologies), and Fungizone Antimycotic (15290, Life Technologies).
Grafting of Murine Melanoma Cells
Recipient mice were intradermally engrafted with 1×106 B16-F10 cells. Mice engrafted with melanoma cells were sacrificed not later than at a time point defined by tumor volume (V >1′000 mm3). Tumor volume was calculated as follows: V=2/3×π×((a+b)/4)3, a (mm) was the length and b (mm) was the width of the tumor.
In Vivo Treatments
Recombinant human IL-2 (IL-2, Teceleukin, Roche), anti-CTLA-4 mAb (9D9, BioXcell), anti-TIM-3 mAb (RMT3-23, BioXcell), anti-PD-1 mAb (RMP1-14, BioXcell) and GSK503 (GlaxoSmithKline) were purchased. IL-2cx were prepared by mixing IL-2 (1.5 μg corresponding to 15′000 IU) and anti-IL-2 mAb (1 μg), as previously described [Letourneau, S., et al., Proc Natl Acad Sci USA, 2010. 107(5): p. 2171-6]. Treatment of B16-F10-engrafted mice was started, when tumors became visible and palpable (days 3-5) [Krieg, C., et al., Proc Natl Acad Sci USA, 2010. 107(26): p. 11906-11]. Where indicated, mice received intraperitoneal injections of IL-2cx, 250 μg of anti-CTLA-4 mAb, or 250 μg of anti-PD-1 mAb or 250 μg of anti-TIM-3 antibody.
Flow Cytometry
Single cell suspensions of spleen and lymph nodes were prepared according to standard protocols. Tumors were cut into small pieces, pooled per groups in order to obtain enough cells for analysis, and incubated in 10 ml dissociation buffer (RPMI, 5% FCS, 10 μg/ml DNAase I [D4527, Sigma-Aldrich] and 200 U/ml collagenase type I [17100-017, Life Technologies]) for 45 minutes at 37° C. and 25 rpm. Cell suspensions were then passed through a 70 μm cell strainer. After one wash a Percoll (17-5445-01, GE Healthcare) gradient centrifugation was performed. All cell suspensions were stained for flow cytometry analysis using PBS with 2% FCS, 2 mM EDTA and fluorochrome-conjugated Abs (Table 2). Samples were acquired with a FACS Canto and analyzed using FlowJo Software.
Number | Date | Country | Kind |
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16150708.2 | Jan 2016 | EP | regional |
16179132.2 | Jul 2016 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2017/050477 | 1/11/2017 | WO | 00 |