Canine Anti-CD20 Antibodies

Abstract

The invention provides canine CD20 specific antibodies, methods of making the antibodies and methods of use of the antibodies.

We claim: 
     
         1 . An isolated antibody or antigen-binding portion thereof that specifically binds canine CD20, wherein said antibody binds the same canine CD20 epitope recognized by the monoclonal antibody produced by the hybridoma cell line having ATCC number PTA-9433 (4F1), ATCC number PTA-9434 (6C8), ATCC number PTA-9435 (14A12), or ATCC number PTA-9436 (18D3). 
     
     
         2 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein the antibody comprises a VH CDR1 of SEQ ID NO:9, 12, 15 or 18; a VH CDR2 of SEQ ID NO:10, 13, 16, or 19; a VH CDR3 of SEQ ID NO:11, 14, 17, or 20; a VL CDR1 of SEQ ID NO:21, 24, 27, or 30; a VL CDR2 of SEQ ID NO:22, 25, 28, or 31; and a VL CDR3 of SEQ ID NO:23, 26, 29, or 32. 
     
     
         3 . An isolated antibody or antigen-binding portion thereof, wherein said antibody or antigen-binding portion specifically binds canine CD20, wherein the antibody or antigen-binding portion thereof competes for binding with a monoclonal antibody produced by the hybridoma cell line having ATCC number PTA-9433 (4F1), ATCC number PTA-9434 (6C8), ATCC number PTA-9435 (14A12), or ATCC number PTA-9436 (18D3) to canine CD20. 
     
     
         4 . The isolated antibody or antigen-binding portion thereof of  claim 3 , wherein said antibody or antigen-binding portion thereof inhibits the binding of a monoclonal antibody produced by the hybridoma cell line having ATCC number PTA-9433 (4F1), ATCC number PTA-9434 (6C8), ATCC number PTA-9435 (14A12), or ATCC number PTA-9436 (18D3) to canine CD20. 
     
     
         5 . The isolated antibody or antigen-binding portion thereof of  claim 3 , wherein said antibody or antigen-binding portion thereof specifically binds canine lymphocytes. 
     
     
         6 . The isolated antibody or antigen-binding portion thereof of  claim 3 , wherein said antibody or antigen-binding portion thereof specifically binds to a polypeptide consisting of an amino acid sequence of SEQ ID NO:36. 
     
     
         7 . An isolated antibody or antigen-binding portion thereof of  claim 3 , wherein said antibody or antigen-binding portion thereof specifically binds to a polypeptide comprising an amino acid sequence of SEQ ID NO:36, and wherein the antibody or antigen-binding portion thereof does not specifically bind to a polypeptide consisting of an amino acid sequence of SEQ ID NO:35. 
     
     
         8 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein the antibody or antigen-binding portion thereof is a monoclonal antibody, a polyclonal antibody, a chimeric antibody, a humanized antibody, a synthetic antibody, a single chain antibody, a diabody, a caninized antibody, a canine antibody, a human antibody, or a CDR-grafted antibody. 
     
     
         9 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein the antibody or antigen-binding portion thereof comprises a VL amino acid sequence of SEQ ID NO:5, 6, 7, or 8. 
     
     
         10 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein said antibody or antigen-binding portion thereof comprises the VH amino acid sequence of SEQ ID NO:1, 2, 3, or 4. 
     
     
         11 . A composition comprising the antibody or antigen-binding portion thereof of  claim 1  and a pharmaceutically acceptable carrier. 
     
     
         12 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein the antibody or antigen-binding portion thereof is an IgG1, an IgG2, an IgG2a, an IgG2b, an IgG3, or an IgG4. 
     
     
         13 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein the antibody or antigen-binding portion thereof specifically binds canine CD20 with an affinity (K d ) of at least about 10 −6  M. 
     
     
         14 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein said antibody or antigen-binding portion thereof induces apoptosis of CD20+ cells. 
     
     
         15 . The isolated antibody or antigen-binding portion thereof of  claim 1 , wherein the antibody or antigen-binding portion thereof comprises the same heavy and light chain polypeptide sequences as an antibody produced by hybridoma ATCC number PTA-9433 (4F1), ATCC number PTA-9434 (6C8), ATCC number PTA-9435 (14A12), or ATCC number PTA-9436 (18D3). 
     
     
         16 . The antibody or antigen-binding portion thereof of  claim 1 , wherein the antibody is produced by the hybridoma cell line having ATCC number PTA-9433 (4F1), ATCC number PTA-9434 (6C8), ATCC number PTA-9435 (14A12), or ATCC number PTA-9436 (18D3). 
     
     
         17 . An isolated cell of hybridoma ATCC number PTA-9433 (4F1), ATCC number PTA-9434 (6C8), ATCC number PTA-9435 (14A12), or ATCC number PTA-9436 (18D3). 
     
     
         18 . An isolated polypeptide comprising SEQ ID NO:1-36. 
     
     
         19 . An isolated polynucleotide encoding the polypeptide of  claim 18 . 
     
     
         20 . An isolated polynucleotide encoding an anti-canine CD20 antibody or antigen-binding portion thereof, wherein said isolated polynucleotide encodes a heavy chain and a light chain, wherein the immunoglobulin heavy chain complementarity determining region (CDR) CDR1 comprises SEQ ID NO:9, 12, 15, or 18, the CDR2 comprises SEQ ID NO:10, 13, 16, or 19, and the CDR3 comprises SEQ ID NO:11, 14, 17 or 20, and wherein the immunoglobulin light chain CDR1 comprises SEQ ID NO:21, 24, 27, or 30, the CDR2 comprises SEQ ID NO:22, 25, 28, or 31, and the CDR3 comprise SEQ ID NO:23, 26, 29 or 32. 
     
     
         21 . A vector comprising one or more polynucleotides of  claim 20 . 
     
     
         22 . A host cell comprising the vector of  claim 21 . 
     
     
         23 . A method for producing a canine anti-CD20 antibody or antigen-binding portion thereof, comprising culturing the isolated host cell of  claim 22  and recovering said antibody. 
     
     
         24 . An isolated antibody or antigen-binding portion thereof that specifically binds to canine CD20, wherein the antibody or antigen-binding portion thereof comprises a heavy chain and a light chain variable domain, wherein the antibody or antigen-binding portion thereof comprises six complementarity determining regions (CDRs), and wherein three of the six CDRs comprise amino acid sequences wherein the antibody variable heavy chain CDRs are selected from SEQ ID NOs:9-20 and wherein the antibody variable light chain CDRs are selected from SEQ ID NOs:21-32.