Anti-CD200R1 antibodies and methods of use thereof

1. An anti-CD200R1 antibody comprising (i) a first light chain hypervariable region (HVR-L1), a second light chain hypervariable region (HVR-L2), and a third light chain hypervariable region (HVR-L3); and (ii) a first heavy chain hypervariable region (HVR-H1), a second heavy chain hypervariable region (HVR-H2), and a third heavy chain hypervariable region (HVR-H3), comprising:

(a) HVR-L1 of SEQ ID NO: 11, HVR-L2 of SEQ ID NO: 12, and HVR-L3 of SEQ ID NO: 13; and HVR-H1 of SEQ ID NO: 15, HVR-H2 of SEQ ID NO: 16, and HVR-H3 of SEQ ID NO: 17;

(b) HVR-L1 of SEQ ID NO: 19, HVR-L2 of SEQ ID NO: 20, and HVR-L3 of SEQ ID NO: 21; and HVR-H1 of SEQ ID NO: 23, HVR-H2 of SEQ ID NO: 24, and HVR-H3 of SEQ ID NO: 25;

(c) HVR-L1 of SEQ ID NO: 27, HVR-L2 of SEQ ID NO: 28, and HVR-L3 of SEQ ID NO: 29; and HVR-H1 of SEQ ID NO: 31, HVR-H2 of SEQ ID NO: 32, and HVR-H3 of SEQ ID NO: 33;

(d) HVR-L1 of SEQ ID NO: 35, HVR-L2 of SEQ ID NO: 36, and HVR-L3 of SEQ ID NO: 37; and HVR-H1 of SEQ ID NO: 39, HVR-H2 of SEQ ID NO: 40, and HVR-H3 of SEQ ID NO: 41;

(e) HVR-L1 of SEQ ID NO: 43, HVR-L2 of SEQ ID NO: 44, and HVR-L3 of SEQ ID NO: 45; and HVR-H1 of SEQ ID NO: 47, HVR-H2 of SEQ ID NO: 48, and HVR-H3 of SEQ ID NO: 49;

(f) HVR-L1 of SEQ ID NO: 51, HVR-L2 of SEQ ID NO: 52, and HVR-L3 of SEQ ID NO: 53; and HVR-H1 of SEQ ID NO: 55, HVR-H2 of SEQ ID NO: 56, and HVR-H3 of SEQ ID NO: 57;

(g) HVR-L1 of SEQ ID NO: 59, HVR-L2 of SEQ ID NO: 60, and HVR-L3 of SEQ ID NO: 61; and HVR-H1 of SEQ ID NO: 63, HVR-H2 of SEQ ID NO: 64, and HVR-H3 of SEQ ID NO: 65;

(h) HVR-L1 of SEQ ID NO: 77, HVR-L2 of SEQ ID NO: 78, and HVR-L3 of SEQ ID NO: 79; and HVR-H1 of SEQ ID NO: 81, HVR-H2 of SEQ ID NO: 82, and HVR-H3 of SEQ ID NO: 83;

(i) HVR-L1 of SEQ ID NO: 11, HVR-L2 of SEQ ID NO: 12, and HVR-L3 of SEQ ID NO: 13; and HVR-H1 of SEQ ID NO: 85, HVR-H2 of SEQ ID NO: 86, and HVR-H3 of SEQ ID NO: 87;

(j) HVR-L1 of SEQ ID NO: 11, HVR-L2 of SEQ ID NO: 12, and HVR-L3 of SEQ ID NO: 13; and HVR-H1 of SEQ ID NO: 81, HVR-H2 of SEQ ID NO: 82, and HVR-H3 of SEQ ID NO: 83; or

(k) HVR-L1 of SEQ ID NO: 77, HVR-L2 of SEQ ID NO: 78, and HVR-L3 of SEQ ID NO: 79; and HVR-H1 of SEQ ID NO: 85, HVR-H2 of SEQ ID NO: 86, and HVR-H3 of SEQ ID NO: 87.

2. The antibody of claim 1 , wherein the antibody comprises a light chain variable domain (V L ) amino acid sequence having at least 90% identity to a sequence selected from SEQ ID NO: 10, 18, 26, 34, 42, 50, 58, 66, or 76.

3. The antibody of claim 1 , wherein

(a) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 10, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 14;

(b) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 18, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 22;

(c) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 26, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 30;

(d) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 34, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 38;

(e) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 42, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 46;

(f) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 50, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 54;

(g) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 58, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 62;

(h) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 66, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 67;

(i) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 76, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 80;

(j) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 66, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 84;

(k) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 66, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 80; or

(l) the antibody comprises a light chain variable domain (VL) amino acid sequence having at least 90% identity to SEQ ID NO: 76, and a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to SEQ ID NO: 84.

4. The antibody of claim 1 , wherein the antibody comprises a light chain (LC) amino acid sequence having at least 90% identity to a sequence selected from SEQ ID NO: 68, 71, and 74.

5. The antibody of claim 1 , wherein the antibody comprises:

(a) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 68; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 69;

(b) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 68; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 70;

(c) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 71; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 88;

(d) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 71; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 72;

(e) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 68; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 89;

(f) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 68; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 73;

(g) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 68; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 88;

(h) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 71; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 89; or

(i) a light chain (LC) amino acid sequence having at least 90% identity to SEQ ID NO: 74; and a heavy chain (HC) amino acid sequence having at least 90% identity to SEQ ID NO: 75.

6. The antibody of claim 1 , wherein the antibody is characterized by:

(a) binds to hu-CD200R1 with a binding affinity of 1×10 −8 M or less;

(b) binds to hu-CD200R1-iso4-Alt or hu-CD200R1-iso4-Ref, and hu-CD200R1-iso1-Alt or hu-CD200R1-iso1-Ref with a binding affinity of 1×10 −8 M or less;

(c) binds to hu-CD200R1-iso4-Alt and hu-CD200R1-iso4-Ref with a binding affinity of 1×10 −8 M or less;

(d) binds to hu-CD200R1-iso4-Alt, hu-CD200R1-iso4-Ref, hu-CD200R1-iso1-Alt, and hu-CD200R1-iso1-Ref with a binding affinity of 1×10 −8 M or less;

(e) binds to cyno-CD200R1 with a binding affinity of 1×10 −8 M or less;

(f) binds to hu-CD200R1 and to cyno-CD200R1 with a binding affinity of 1×10 −8 M or less;

(g) blocks hu-CD200-Fc binding to hu-CD200R1-iso4-Alt (SEQ ID NO: 1), hu-CD200R1-iso4-Ref (SEQ ID NO: 2), hu-CD200R1-iso1-Alt (SEQ ID NO: 3), and hu-CD200R1-iso1-Ref (SEQ ID NO: 4) measured by ELISA with an IC 50 of 10 nM or less;

(h) blocks hu-CD200-Fc binding to hu-CD200R1 expressed on a cell with an IC 50 of 2.5 nM or less;

(i) binds to human T-cells with an EC 50 of 2.5 nM or less;

(j) increases IFNγ production from human tumor cells by at least 1.2-fold with an antibody concentration of 100 nM or less;

(k) increases IFNγ or IL-2 production from hu-CD200-Fc coated human T cells relative to IgG control by at least 1.2-fold;

(l) increases activation of human CD4+ T-cells or human Cd8+ T-cells by at least 1.5-fold;

(m) does not agonize CD200R1 signaling;

(n) blocks induction of pDok2 activity in U937 monocytic cell lines treated with soluble hu-CD200-Fc; or

(o) blocks NFkβ transcription induced by hu-CD200 binding hu-CD200R1 expressing cell-lines.

7. A pharmaceutical composition comprising an anti-CD200R1 antibody of claim 1 and a pharmaceutically acceptable carrier.

8. The antibody of claim 1 , wherein the antibody comprises a heavy chain variable domain (VH) amino acid sequence having at least 90% identity to a sequence selected from SEQ ID NO: 14, 22, 30, 38, 46, 54, 62, 67, 80, or 84.

9. The antibody of claim 1 , wherein the antibody comprises a heavy chain (HC) amino acid sequence having at least 90% identity to a sequence selected from SEQ ID NO: 69, 70, 72, 73, 75, 88, and 89.

10. The pharmaceutical composition of claim 7 , wherein the composition further comprises a chemotherapeutic agent or an antibody comprising a specificity for an immune checkpoint molecule.

11. The pharmaceutical composition of claim 7 , wherein the anti-CD200R1 antibody is the sole active agent of the composition.

12. An anti-CD200R1 antibody comprising (i) the heavy chain (HC) amino acid sequence of SEQ ID NO: 69, and (ii) the light chain (LC) amino acid sequence of SEQ ID NO: 68.

13. An anti-CD200R1 antibody comprising (i) the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 67, and (ii) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 66.

14. The antibody of claim 1 , wherein the antibody binds to hu-CD200R1 with a binding affinity of 1×10 −8 M or less, wherein the binding affinity is measured by equilibrium dissociation constant (K D ) to a hu-CD200R1 polypeptide of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4.

15. The antibody of claim 1 , wherein the antibody binds to hu-CD200R1-iso4-Alt or hu-CD200R1-iso4-Ref, and hu-CD200R1-iso1-Alt, with a binding affinity of 1×10 −8 M or less, wherein the binding affinity is measured by equilibrium dissociation constant (K D ) to a hu-CD200R1-iso4-Alt polypeptide of SEQ ID NO: 1 or a hu-CD200R1-iso4-Ref polypeptide of SEQ ID NO: 2, and a hu-CD200R1-iso1-Alt polypeptide of SEQ ID NO: 3.

16. The antibody of claim 1 , wherein the antibody binds to hu-CD200R1-iso4-Alt or hu-CD200R1-iso4-Ref, and hu-CD200R1-iso1-Ref with a binding affinity of 1×10 −8 M or less, wherein the binding affinity is measured by equilibrium dissociation constant (K D ) to a hu-CD200R1-iso4-Alt polypeptide of SEQ ID NO: 1 or a hu-CD200R1-iso4-Ref polypeptide of SEQ ID NO: 2, and a hu-CD200R1-iso1-Ref polypeptide of SEQ ID NO: 4.

17. The antibody of claim 1 , wherein the antibody binds to hu-CD200R1-iso4-Alt and hu-CD200R1-iso4-Ref with a binding affinity of 1×10 −8 M or less wherein the binding affinity is measured by equilibrium dissociation constant (K D ) to a hu-CD200R1-iso4-Alt polypeptide of SEQ ID NO: 1, and a hu-CD200R1-iso4-Ref polypeptide of SEQ ID NO: 2.

18. The antibody of claim 1 , wherein the antibody binds to hu-CD200R1-iso4-Alt, hu-CD200R1-iso4-Ref, hu-CD200R1-iso1-Alt, and hu-CD200R1-iso1-Ref with a binding affinity of 1×10 −8 M or less, wherein the binding affinity is measured by equilibrium dissociation constant (K D ) to a hu-CD200R1-iso4-Alt polypeptide of SEQ ID NO: 1, or a hu-CD200R1-iso4-Ref polypeptide of SEQ ID NO: 2, and a huCD200R1-iso1-Alt polypeptide of of SEQ: 4 or a huCD200R1-iso1-Ref polypeptide of SEQ: 3.

19. The antibody of claim 1 , wherein the antibody binds to cyno-CD200R1 with a binding affinity of 1×10 −8 M or less, wherein the binding affinity is measured by equilibrium dissociation constant (K D ) to a cyno-CD200R1 polypeptide of SEQ ID NO: 5.

20. The antibody of claim 1 , wherein the antibody binds to a hu-CD200R1 isoform and to cyno-CD200R1 with a binding affinity of 1×10 −8 M or less, wherein the binding affinity is measured by equilibrium dissociation constant (K D ) to a hu-CD200R1 polypeptide of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4, and a cyno-CD200R1 polypeptide of SEQ ID NO: 5.

21. The antibody of claim 1 , wherein the antibody blocks hu-CD200-Fc binding to hu-CD200R1 expressed on a cell with an IC50 of 2.5 nM or less, wherein the cell is a U937 cell stably expressing hu-CD200R1.

22. The antibody of claim 1 , wherein the antibody binds to human T-cells with an EC50 of 2.5 nM or less, wherein the human T cells are CD4+ T cells or CD8+ T cells.

23. The antibody of claim 1 , wherein the antibody increases IFNγ production from human tumor cells by at least 1.2-fold, with an antibody concentration of 100 nM or less, wherein the tumor cell is of a type is selected from colorectal, endometrial, lung, melanoma, ovarian, pancreatic, or prostate.

24. The antibody of claim 1 , wherein the antibody blocks NFkβ transcription induced by a hu-CD200 of a hu-CD200-expressing K562 cell binding to a hu-CD200R1 of a hu-CD200R1.

25. An anti-CD200R1 antibody comprising:

(a) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 10, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 14;

(b) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 18, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 22;

(c) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 26, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 30;

(d) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 34, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 38;

(e) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 42, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 46;

(f) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 50, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 54;

(g) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 58, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 62;

(h) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 66, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 67;

(i) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 76, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 80;

(j) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 66, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 84;

(k) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 66, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 80; or

(l) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 76, and the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 84.

26. An anti-CD200R1 antibody comprising:

(a) the light chain (LC) amino acid sequence of SEQ ID NO: 68; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 69;

(b) the light chain (LC) amino acid sequence of SEQ ID NO: 68; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 70;

(c) the light chain (LC) amino acid sequence of SEQ ID NO: 71; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 88;

(d) the light chain (LC) amino acid sequence of SEQ ID NO: 71; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 72;

(e) the light chain (LC) amino acid sequence of SEQ ID NO: 68; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 89;

(f) the light chain (LC) amino acid sequence of SEQ ID NO: 68; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 73;

(g) the light chain (LC) amino acid sequence of SEQ ID NO: 68; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 88;

(h) the light chain (LC) amino acid sequence of SEQ ID NO: 71; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 89; or

(i) the light chain (LC) amino acid sequence of SEQ ID NO: 74; and the heavy chain (HC) amino acid sequence of SEQ ID NO: 75.

27. An anti-CD200R1 antibody comprising (i) a first light chain hypervariable region (HVR-L1), a second light chain hypervariable region (HVR-L2), and a third light chain hypervariable region (HVR-L3); and (ii) a first heavy chain hypervariable region (HVR-H1), a second heavy chain hypervariable region (HVR-H2), and a third heavy chain hypervariable region (HVR-H3), comprising HVR-L1 of SEQ ID NO: 11, HVR-L2 of SEQ ID NO: 12, and HVR-L3 of SEQ ID NO: 13; and HVR-H1 of SEQ ID NO: 15, HVR-H2 of SEQ ID NO: 16, and HVR-H3 of SEQ ID NO: 17.

28. An anti-CD200R1 antibody comprising (i) a first light chain hypervariable region (HVR-L1), a second light chain hypervariable region (HVR-L2), and a third light chain hypervariable region (HVR-L3); and (ii) a first heavy chain hypervariable region (HVR-H1), a second heavy chain hypervariable region (HVR-H2), and a third heavy chain hypervariable region (HVR-H3), comprising HVR-L1 of SEQ ID NO: 77, HVR-L2 of SEQ ID NO: 78, and HVR-L3 of SEQ ID NO: 79; and HVR-H1 of SEQ ID NO: 81, HVR-H2 of SEQ ID NO: 82, and HVR-H3 of SEQ ID NO: 83.

29. An anti-CD200R1 antibody comprising (i) the heavy chain (HC) amino acid sequence of SEQ ID NO: 88, and (ii) the light chain (LC) amino acid sequence of SEQ ID NO: 71.

30. An anti-CD200R1 antibody comprising (i) the heavy chain variable domain (VH) amino acid sequence of SEQ ID NO: 80, and (ii) the light chain variable domain (VL) amino acid sequence of SEQ ID NO: 76.