CD47 antibodies and methods of use thereof
This invention relates generally to monoclonal antibodies that recognize CD47, more specifically to CD47 antibodies that do not cause a significant level of agglutination of cells, to methods of generating these antibodies, and to methods of using these monoclonal antibodies as therapeutics.
1. A method of alleviating a symptom of a cancer or other neoplastic condition, the method comprising administering an isolated monoclonal antibody or an immunologically active fragment thereof that binds to human CD47 to a subject in need thereof in an amount sufficient to alleviate the symptom of the cancer or other neoplastic condition in the subject, wherein the antibody or immunologically active fragment thereof comprises:
a variable heavy (VH) chain CDR1 amino acid sequence set forth in SEQ ID NO: 50, SEQ ID NO: 57, SEQ ID NO: 58, SEQ ID NO: 59, SEQ ID NO: 60, SEQ ID NO: 61, SEQ ID NO: 62, SEQ ID NO: 63, SEQ ID NO: 64, SEQ ID NO: 65, or SEQ ID NO: 66;
a VH chain CDR2 amino acid sequence set forth in SEQ ID NO: 51, SEQ ID NO: 72, SEQ ID NO: 73, SEQ ID NO: 74, SEQ ID NO: 75, or SEQ ID NO: 76;
a VH chain CDR3 amino acid sequence set forth in SEQ ID NO: 52 or SEQ ID NO: 77;
a variable light (VL) chain CDR1 amino acid sequence set forth in SEQ ID NO: 53, SEQ ID NO: 67, or SEQ ID NO: 68;
a VL chain CDR2 amino acid sequence set forth in SEQ ID NO: 54, SEQ ID NO: 69, SEQ ID NO: 70, or SEQ ID NO: 71; and
a VL chain CDR3 sequence set forth in SEQ ID NO: 55.
2. The method of claim 1 , wherein the subject is a human.
3. The method of claim 1 , wherein the antibody or immunologically active fragment thereof is chimeric or humanized.
4. The method of claim 1 , wherein the antibody or immunologically active fragment thereof prevents CD47 from interacting with SIRPα.
5. The method of claim 1 , wherein the antibody or immunologically active fragment thereof is of an IgG isotype selected from the group consisting of IgG1 isotype, IgG2 isotype, IgG3 isotype, and IgG4 isotype.
6. The method of claim 1 , wherein the antibody or immunologically active fragment thereof is of an IgG isotype selected from IgG4P and IgG4PE.
7. The method of claim 1 , further comprising administering chemotherapy.
8. The method of claim 7 , wherein said chemotherapy is radiotherapy.
9. The method of claim 1 , wherein the antibody or immunologically active fragment thereof promotes macrophage-mediated phagocytosis of a CD47-expressing cell.
10. The method of claim 1 , wherein the antibody or immunologically active fragment thereof comprises a VH chain sequence selected from the group consisting of SEQ ID NOs: 5-30.
11. The method of claim 1 , wherein the antibody or immunologically active fragment thereof comprises a VL chain sequence selected from the group consisting of SEQ ID NOs: 31-47.
12. The method of claim 1 , wherein the antibody or immunologically active fragment thereof comprises a VH chain sequence provided in any one of SEQ ID NOs: 5-30 and a VL chain sequence provided in any one of SEQ ID NOs: 31-47.
13. The method of claim 1 , wherein the antibody or immunologically active fragment thereof comprises a VH chain sequence provided in any one of SEQ ID NOs: 5, 7, 8, 11, 12, 15-17, 20-22, and 27-30 and a VL chain sequence provided in any one of SEQ ID NOs: 31, 32, 35, 40, 41, 42, 43, 44, and 47.
14. The method of claim 1 , wherein the antibody or immunologically active fragment thereof comprises the VH chain CDR1 sequence set forth in SEQ ID NO: 50; the VH chain CDR2 sequence set forth in SEQ ID NO: 51; the VH chain CDR3 sequence set forth in SEQ ID NO: 52; the VL chain CDR1 sequence set forth in SEQ ID NO: 53; the VL chain CDR2 sequence set forth in SEQ ID NO: 54; and the VL chain CDR3 sequence set forth in SEQ ID NO: 55.
15. The method of claim 1 , wherein the antibody or immunologically active fragment thereof comprises the VH chain CDR1 sequence set forth in SEQ ID NO: 50; the VH chain CDR2 sequence set forth in SEQ ID NO: 72; the VH chain CDR3 sequence set forth in SEQ ID NO: 52; the VL chain CDR1 set forth in SEQ ID NO: 53; the VL chain CDR2 sequence set forth in SEQ ID NO: 71; and the VL chain CDR3 sequence set forth in SEQ ID NO: 55.
16. The method of claim 1 , wherein the antibody or immunologically active fragment thereof binds to CD47 in a head to side orientation, wherein a VH chain of the antibody is positioned near the membrane of a CD47 expressing cell, and wherein a VL chain of the antibody occludes a SIRPα binding site on CD47.
17. The method of claim 1 , wherein the antibody or immunologically active fragment thereof binds to a discontinuous epitope on CD47.
18. The method of claim 17 wherein the antibody or immunologically active fragment thereof binds to a CD47 loop comprising SEQ ID NO: 56.
19. The method of claim 18 , wherein the discontinuous epitope comprises amino acid residues Y37, K39, K41, K43, G44, R45, D46, D51, H90, N93, E97, T99, E104, or E106 of CD47 when numbered in accordance with SEQ ID NO: 147.
20. The method of claim 1 , wherein the antibody or immunologically active fragment thereof does not cause a significant level of hemagglutination of red blood cells after administration.
21. The method of claim 1 , wherein the cancer is a hematological cancer.
22. A method of alleviating a symptom of a cancer or other neoplastic condition, the method comprising administering an isolated monoclonal antibody or an immunologically active fragment thereof that binds to CD47 to a subject in need thereof in an amount sufficient to alleviate the symptom of the cancer or other neoplastic condition in the subject, wherein the antibody or immunologically active fragment thereof comprises:
a VH CDR1, a VH CDR2, and a VH CDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a VH chain having the sequence set forth in any of SEQ ID NOs: 5-30; and
a VL CDR1, a VL CDR2, and a VLCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a VL chain having the sequence set forth in any of SEQ ID NOs: 31-47.