PVRIG polypeptides and methods of treatment

A method of screening for anti-PVRIG antibodies and fragments thereof, wherein the method comprises:

• i) providing a first cell comprising an exogenous recombinant nucleic acid encoding a human PVRIG polypeptide, wherein the first cell expresses the human PVRIG polypeptide;
• ii) contacting the first cell with a second cell comprising another exogenous recombinant nucleic acid encoding a human PVRL2 polypeptide, wherein the second cell expresses the human PVRL2 polypeptide, in the presence of a candidate agent comprising an antibody or fragment thereof;
• and
• iii) determining whether the first cell binds to the second cell as an indication of whether the candidate agent comprising an antibody or fragment thereof comprises an anti-PVRIG antibody or a fragment thereof that inhibits the binding of PVRIG with PVRL2.