Canine CD20 Compositions

Abstract

The invention provides canine CD20 nucleotide and protein sequences. These compositions are useful in the diagnosis and treatment of, e.g., CD20+ B-cell lymphoma, immune-mediated hemolytic anemia, immune-mediated thrombocytopenia, and systemic lupus erythematosus (SLE) in canines and felines.

1 . An isolated antibody or antigen binding portion thereof that specifically binds SEQ ID NO:6 or SEQ ID NO:10.  
     
     
         2 . The isolated antibody or antigen binding portion thereof of  claim 1 , wherein the isolated antibody or antigen binding portion thereof is a monoclonal antibody, a polyclonal antibody, or single chain antibody.  
     
     
         3 . The isolated antibody of  claim 2 , wherein the antibody is produced by myeloma cell line ATCC PTA-6661 or ATCC PTA-6662.  
     
     
         4 . The antigen binding portion thereof of  claim 2 , wherein the antigen binding portion thereof is a Fab fragment, a F(ab′) 2  fragment, a Fab′ fragment, a F(ab) 2  fragment, a sFv fragment, a single chain antibody, or a Fv fragment.  
     
     
         5 . The isolated antibody or antigen binding portion thereof of  claim 1 , wherein the antibody or antigen binding portion thereof belongs to an antibody class selected from the group consisting of IgG, IgM, IgA, IgD and IgE.  
     
     
         6 . An isolated antibody or antigen binding fragment thereof that (a) competes with a reference antibody for binding to SEQ ID NOs:6 or 10 or antigen binding fragments thereof; (b) binds to the same epitope of SEQ ID NOs:6 or 10 or antigen binding fragments thereof as a reference antibody; (c) binds to SEQ ID NOs:6 or 10 or antigen binding fragments thereof with substantially the same K d  as a reference antibody; or (d) binds to SEQ ID NOs:6 or 10 or antigen binding fragments thereof with substantially the same off rate as a reference antibody, wherein the reference antibody is an antibody or antigen binding fragment thereof that specifically binds to a polypeptide of SEQ ID NOs:6 or 10 or antigen binding fragments thereof with a binding affinity K a  of 10 7  l/mol or more.  
     
     
         7 . An isolated antibody or antigen binding fragment thereof that competes with the isolated antibody of  claim 3  for binding to SEQ ID NOs:6 or 10 or antigen binding fragments thereof.