Antibodies directed against programmed death-1 (PD-1)

1. A PD-1 binding agent comprising: a heavy chain immunoglobulin polypeptide comprising a complementarity determining region (CDR) 1 comprising the amino acid sequence of SEQ ID NO: 19; a CDR 2 comprising the amino acid sequence of SEQ ID NO: 20; and a CDR 3 comprising the amino acid sequence of SEQ ID NO: 21; and a light chain immunoglobulin polypeptide comprising a CDR 1 comprising the amino acid sequence of SEQ ID NO: 35; a CDR 2 comprising the amino acid sequence of SEQ ID NO: 36 except that residue 5 of SEQ ID NO: 36 is replaced with a leucine (L) residue; and a CDR 3 comprising the amino acid sequence of SEQ ID NO: 37.

2. The PD-1 binding agent of claim 1 , wherein the heavy chain immunoglobulin polypeptide comprises the amino acid sequence of SEQ ID NO: 23.

3. The PD-1 binding agent of claim 1 , wherein the light chain immunoglobulin polypeptide comprises the amino acid sequence of SEQ ID NO: 40.

4. The PD-1 binding agent of claim 1 , wherein the heavy chain immunoglobulin polypeptide comprises SEQ ID NO: 23, and the light chain immunoglobulin polypeptide comprises SEQ ID NO: 40.

5. The PD-1 binding agent of claim 1 , wherein the PD-1 binding agent is an antibody or an antigen-binding fragment thereof.

6. The PD-1 binding agent of claim 5 , wherein the PD-1 binding agent comprises an IgG1, IgG2, or IgG4 heavy chain constant region (Fc).

7. The PD-1 binding agent of claim 1 , wherein the PD-1 binding agent is an antibody comprising a heavy chain immunoglobulin polypeptide comprising SEQ ID NO: 23, a light chain immunoglobulin polypeptide comprising SEQ ID NO: 40, and an IgG4 heavy chain constant region (Fc).

8. An isolated nucleic acid sequence encoding the heavy chain immunoglobulin polypeptide or the light chain immunoglobulin polypeptide of claim 1 .

9. An isolated nucleic acid sequence encoding the heavy chain immunoglobulin polypeptide or the light chain immunoglobulin polypeptide of claim 4 .

10. A vector comprising the nucleic acid of claim 8 .

11. A vector comprising the nucleic acid of claim 9 .

12. A host cell comprising the vector of claim 10 .

13. A host cell comprising the vector of claim 11 .

14. The host cell of claim 12 , wherein the host cell is a mammalian host cell.

15. The host cell of claim 13 , wherein the host cell is a mammalian host cell.

16. A pharmaceutical composition comprising the PD-1 binding agent of claim 1 and a pharmaceutically acceptable carrier or diluent.

17. A pharmaceutical composition comprising the PD-1 binding agent of claim 4 and a pharmaceutically acceptable carrier or diluent.

18. The pharmaceutical composition of claim 16 , wherein the pharmaceutical composition is formulated for parenteral administration.

19. The pharmaceutical composition of claim 17 , wherein the pharmaceutical composition is formulated for parenteral administration.

20. A method of producing the PD-1 binding agent of claim 1 , the method comprising expressing a nucleic acid encoding the PD-1 binding agent in a cell.

21. A method of treating a cancer in a human comprising administering to the human an effective amount of the PD-1 binding agent of claim 1 .

22. A method of enhancing an immune response or increasing the activity of an immune cell comprising contacting an effective amount of the PD-1 binding agent of claim 1 to the immune cell.

23. The method of claim 22 , wherein the immune response or activity is a cell mediated immune response.

24. The method of claim 22 , wherein the immune response or activity is a CD8 T cell response.

25. The method of claim 22 , further comprising contacting the immune cell with an anti-TIM-3 antibody or an anti-LAG 3 antibody.

26. The method of claim 21 , further comprising administering an anti-TIM-3 antibody or an anti-LAG-3 antibody to the mammal.

27. The method of claim 22 , wherein the immune cell is in a human.

28. The method of claim 27 , wherein the human has a disorder that is cancer or an infectious disease.

29. The method of claim 28 , wherein the disorder is cancer.

30. The method of claim 21 or 22 , wherein the half-life of the PD-1 binding agent is between 30 minutes and 45 days.

31. The method of claim 21 or 22 , wherein the PD-1 binding agent binds to PD-1 with a K D between about 1 picomolar (pM) and about 100 micromolar (μM).

32. The method of claim 21 or claim 29 , wherein the cancer is characterized by expression of PD-1 or PD-L1.

33. The method of claim 21 or claim 29 , wherein the cancer is selected from the group consisting of: melanoma, renal cell carcinoma, lung cancer, bladder cancer, breast cancer, cervical cancer, colon cancer, gall bladder cancer, laryngeal cancer, liver cancer, thyroid cancer, stomach cancer, salivary gland cancer, prostate cancer, pancreatic cancer, and Merkel cell carcinoma.

34. The method of claim 22 , wherein the step of contacting comprises administering a pharmaceutical composition that delivers the PD-1 binding agent to a human.

35. An isolated nucleic acid sequence encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of claim 1 .

36. An isolated nucleic acid sequence encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of claim 4 .

37. A vector comprising the nucleic acid of claim 35 .

38. A vector comprising the nucleic acid of claim 36 .

39. A host cell comprising the vector of claim 37 .

40. A host cell comprising the vector of claim 38 .

41. A host cell comprising a nucleic acid encoding the heavy chain immunoglobulin polypeptide of claim 1 and a nucleic acid encoding the light chain immunoglobulin polypeptide of claim 1 .

42. A host cell comprising a nucleic acid encoding the heavy chain immunoglobulin polypeptide of claim 4 and a nucleic acid encoding the light chain immunoglobulin polypeptide of claim 4 .

43. A cell line that produces the PD-1 binding agent of claim 1 .

44. A cell line that produces the PD-1 binding agent of claim 4 .