Immunopotentiative composition

Abstract

The compositions of the present invention that inhibits the function of PD-1, PD-L1, or PD-L2 are useful for cancer or infection treatment.

1 . (canceled) 
     
     
         2 . A method of treating a tumor in a subject in need thereof comprising administering to the subject an immunosuppressive signal inhibitor of PD-1, PD-L1, or PD-L2. 
     
     
         3 . The method of  claim 2 , wherein the immunosuppressive signal inhibitor suppresses cancer metastasis. 
     
     
         4 . A method of treating an infection in a subject in need thereof comprising administering to the subject an immunosuppressive signal inhibitor of PD-1, PD-L1 or PD-L2. 
     
     
         5 . The method of  claim 2 , wherein the immunosuppressive signal inhibitor acts through immunopotentiation. 
     
     
         6 . The method of  claim 4 , wherein the immunosuppressive signal inhibitor acts through immunopotentiation. 
     
     
         7 . The method of  claim 2 , wherein the immunosuppressive signal inhibitor is one or more selected from the group consisting of an interaction inhibitor of PD-1 and PD-L1 or PD-1 and PD-L2, an intracellular signaling inhibitor of PD-1, and a production inhibitor of PD-1, PD-L1 or PD-L2. 
     
     
         8 . The method of  claim 7 , wherein the interaction inhibitor of PD-1 and PD-L1 is one or more selected from the group consisting of an anti-PD-1 antibody, an anti-PD-L1 antibody, soluble PD-1, and soluble PD-L1. 
     
     
         9 . The method of  claim 8 , wherein the anti-PD-1 antibody is selected from the group consisting of an anti-human PD-1 antibody produced by a hybridoma internationally deposited as FERM BP-8392, a humanized anti-human PD-1 antibody, and a human anti-human PD-1 antibody. 
     
     
         10 . The method of  claim 2 , wherein the immunosuppressive signal inhibitor is a lymphocyte in which PD-1 expression is inhibited by gene-recombination. 
     
     
         11 . The method of  claim 7 , wherein the interaction inhibitor of PD-1 and PD-L1 or PD-1 and PD-L2, the intracellular signaling inhibitor of PD-1, or the production inhibitor of PD-1, PD-L1 or PD-L2 is one or more substances selected from a protein, a polypeptide, a peptide, a polynucleotide, a polynucleoside, an antibody or a derivative thereof, an organic synthesis compound, an inorganic compound, and a natural product. 
     
     
         12 - 28 . (canceled) 
     
     
         29 . A method of screening for a substance for treatment of cancer, comprising contacting a test substance with a carcinoma cell expressing PD-L1 or PD-L2 and a lymphocyte, wherein the test substance enhances an immune reaction of the lymphocyte to the carcinoma cell and thereby inhibits carcinoma cell proliferation. 
     
     
         30 . A method of screening for a substance for treatment of infection, comprising contacting a test substance with a cell, which expresses PD-L1 or PD-L2 and is infected with a pathogen and a lymphocyte, wherein the test substance enhances immune reaction of the lymphocyte to the infected cell and thereby inhibits pathogen proliferation. 
     
     
         31 - 32 . (canceled)