Antitumor antibodies, proteins, and uses thereof

Abstract

Antibodies that bind to a 40 kDa protein which is expressed on tumors, but is not expressed on normal adult hemopoietic cells are disclosed. Also disclosed are methods for production and the use of such antibodies.

1 . A monoclonal antibody, or antigen-binding fragment thereof, wherein the monoclonal antibody: 
 (a) binds to fetal thymocytes;    (b) inhibits cell proliferation of a cell upon binding to the cell; and    (c) does not bind to adult thymocytes.    
     
     
         2 . The monoclonal antibody of  claim 1 , wherein the antibody induces homotypic aggregation upon binding to a cell.  
     
     
         3 . The monoclonal antibody of  claim 1 , wherein the antibody induces apoptosis in a cell to which it binds.  
     
     
         4 . The monoclonal antibody of  claim 1 , wherein the antibody specifically binds to one or more tumor cell lines in the group E710.2.3, RMA-S, CTLL, LB17.4, A20, WEHI-231, PBK101A2, C2.3, B16, MC57, WOP-3027, 293T, 143Btk, Jurkat, and Cos.  
     
     
         5 . The monoclonal antibody of  claim 4 , wherein the antibody specifically binds to E710.2.3 cells.  
     
     
         6 . The monoclonal antibody of  claim 1 , wherein the monoclonal antibody is DMF10.62.3 produced by a hybridoma cell line ATCC No. PTA-377.  
     
     
         7 . The monoclonal antibody of  claim 1 , wherein the monoclonal antibody is DMF10.167.4 produced by a hybridoma cell line ATCC No. PTA-405.  
     
     
         8 . The monoclonal antibody of  claim 1 , wherein the monoclonal antibody is DMF10.34.36 produced by a hybridoma cell line ATCC No. PTA-404.  
     
     
         9 . A monoclonal antibody, or antigen binding fragment thereof, that binds to a protein bound by a monoclonal antibody produced by hybridoma cell line ATCC No. PTA-377, PTA-404, or PTA-405.  
     
     
         10 . The monoclonal antibody of  claim 9 , wherein the antibody is humanized.  
     
     
         11 . The monoclonal antibody of  claim 9 , wherein the antibody is a chimeric monoclonal antibody comprising non-human variable regions and human constant regions of light and heavy chains.  
     
     
         12 . A monoclonal antibody, or antigen-binding fragment thereof, that binds to an epitope bound by a monoclonal antibody produced by hybridoma cell line ATCC No. PTA-377, PTA-404, or PTA-405.  
     
     
         13 . A monoclonal antibody, or antigen-binding fragment thereof, that binds specifically to a protein characterized by: 
 (i) a molecular weight of 40 kDa;    (ii) expression on the surface of fetal thymocytes;    (iii) no expression on the surface of adult thymocytes;    (iv) the ability to block cell proliferation upon binding by the antibody; and    (v) the ability to induce homotypic aggregation upon binding by the antibody.    
     
     
         14 . The monoclonal antibody of  claim 13 , wherein the protein is further characterized by: 
 (vi) the ability to induce apoptosis in a cell upon binding by the antibody.    
     
     
         15 . The monoclonal antibody of  claim 13 , wherein the protein is further characterized by: 
 (vii) expression on the cell surface of one or more tumor cell lines consisting of E710.2.3, RMA-S, CTLL, LB17.4, A20, WEHI-231, PBK101A2, C2.3, B16, MC57, WOP-3027, 293T, 143Btk, Jurkat, and Cos.    
     
     
         16 . An antigen-binding fragment of a monoclonal antibody of  claim 1 .  
     
     
         17 . A monoclonal antibody of  claim 1  further comprising a detectable label.  
     
     
         18 . A hybridoma cell line which produces the monoclonal antibody of  claim 1 .  
     
     
         19 . The hybridoma cell line of  claim 18 , wherein the hybridoma cell line is cell line ATCC No. PTA-377, ATCC No. PTA-404 or ATCC No. PTA-405.  
     
     
         20 . A substantially pure protein characterized by: 
 (i) a molecular weight of 40 kDa;    (ii) expression on the surface of fetal thymocytes;    (iii) no expression on the surface of adult thymocytes;    (iv) the ability to block cell proliferation upon binding by the antibody of  claim 1;  and    (v) the ability to induce homotypic aggregation upon binding by the antibody of  claim 1 .    
     
     
         21 . The protein of  claim 20 , wherein the protein is further characterized by: 
 (vi) expression on one or more tumor cell lines consisting of E710.2.3, RMA-S, CTLL, LB17.4, A20, WEHI-231, PBK101A2, C2.3, B16, MC57, WOP-3027, 293T, 143Btk, Jurkat and Cos.    
     
     
         22 . The protein of  claim 20 , wherein the protein is further characterized by: 
 (vii) the ability to induce apoptosis in a cell upon binding of an antibody, wherein the antibody: 
 (a) binds to fetal thymocytes;  
 (b) inhibits cell proliferation of a cell upon binding to the cell; and  
 (c) does not bind to adult thymocytes.  
   
     
     
         23 . The protein of  claim 20  that binds to the monoclonal antibody produced by hybridoma cell line ATCC No. PTA-377, PTA-404, or PTA-405.  
     
     
         24 . A pharmaceutical composition comprising the monoclonal antibody of  claim 1  and a pharmaceutically acceptable carrier.  
     
     
         25 . The method of  claim 36 , wherein the tumor cell is a thymic lymphoma, T-cell tumor, a B-cell lymphoma, melanoma, osteosarcoma, or acute T-cell leukemia cell.  
     
     
         26 . The method of  claim 36 , wherein the tumor cell is in a patient.  
     
     
         27 . A method of inhibiting tumor cell proliferation, the method comprising: 
 contacting the tumor cell with a quantity of a monoclonal antibody of  claim 1 , sufficient to inhibit proliferation of the tumor cell    
     
     
         28 . A method of inducing apoptosis in a cell, the method comprising: 
 contacting the cell with a quantity of the monoclonal antibody of  claim 1 , sufficient to induce apoptosis in the cell.    
     
     
         29 . The method of  claim 28 , wherein the cell is a tumor cell selected from the group consisting of thymic lymphoma, T-cell tumor, a B-cell lymphoma, melanoma, osteosarcoma, and acute T-cell leukemia.  
     
     
         30 . The method of  claim 28 , wherein the cell is in vitro or in vivo.  
     
     
         31 . A kit for tumor diagnosis, comprising the monoclonal antibody of  claim 1 , and instructions for its use.  
     
     
         32 . The kit of  claim 31 , wherein the tumor to be diagnosed is selected from the group consisting of thymic lymphoma, T cell tumor, a B-cell lymphoma, melanoma, osteosarcoma, and acute T cell leukemia.  
     
     
         33 . A tumor cell targeting agent comprising the monoclonal antibody of  claim 1  conjugated to a moiety.  
     
     
         34 . A method of selectively delivering a moiety to a tumor cell in a mammal, the method comprising: 
 administering to the mammal the targeting agent of  claim 33;  and    allowing sufficient time for the complex to reach the tumor cell and the antibody to bind to the tumor cell, thereby selectively delivering the moiety to the tumor cell in the mammal.    
     
     
         35 . A method of isolating a protein, the method comprising: 
 contacting a sample containing proteins with the monoclonal antibody of  claim 1  for a time and under conditions sufficient to enable the formation of antibody protein complexes;    removing the complex, if any, from the sample; and    removing the protein from the complex, thereby isolating the protein.    
     
     
         36 . A method for detecting a tumor cell in a subject, the method comprising: 
 contacting a cell sample from the subject with a monoclonal antibody of  claim 1  under conditions sufficient to enable specific binding; and    detecting any specific binding of the antibody to one or more cells in the sample, wherein binding indicates the presence of a tumor cell in the subject.