Anti-Muc1 Alpha/Beta Antibodies

Abstract

The present invention provides antibodies that simultaneously bind the α- and β-subunits of an intact MUC1 protein, and methods for making and using such antibodies.

1 . A MUC1-specific antibody that binds specifically to an intact MUC1 protein with the proviso that the antibody does not substantially bind to either the cc subunit or the P subunit in the absence of the other. 
     
     
         2 . The antibody of  claim 1 , wherein the antibody binds to isoform MUC1/X but does not substantially bind to isoform MUC1/Y. 
     
     
         3 . The antibody of  claim 2 , wherein the isoform MUC1/X is cleaved into a truncated a subunit and a β subunit. 
     
     
         4 . The antibody of  claim 1 , wherein the antibody is a monoclonal antibody. 
     
     
         5 . The antibody of  claim 1 , wherein the antibody has a titer of from about 1:300 to about 1:30,000. 
     
     
         6 . The antibody of  claim 1 , wherein the antibody is an IgM. 
     
     
         7 . The antibody of  claim 1 , wherein the antibody is DMC209. 
     
     
         8 . The antibody of  claim 1 , wherein the antibody is an IgG. 
     
     
         9 . The antibody of  claim 1 , wherein the antibody is DMC111. 
     
     
         10 . The antibody of  claim 1 , wherein the antibody is humanized. 
     
     
         11 . The antibody of  claim 1 , wherein the antibody is human. 
     
     
         12 . The antibody of  claim 1 , wherein the antibody is a recombinant single chain variable region fragment of an antibody. 
     
     
         13 . The antibody of  claim 1 , further comprising a cytotoxic moiety. 
     
     
         14 . The antibody of  claim 1 , further comprising a label moiety. 
     
     
         15 . The antibody of  claim 1 , wherein the antibody prevents the disassociation of the α subunit from the β subunit. 
     
     
         16 . A cell comprising an antibody of  claim 1 . 
     
     
         17 . The cell of  claim 16 , wherein the cell is a hybridoma cell. 
     
     
         18 . The cell of  claim 16 , wherein the cell comprises an intact MUC1 protein on its surface bound to an antibody of  claim 1 . 
     
     
         19 . A method of targeting an immunotoxin to a cancer cell overexpressing MUC1 comprising administering an antibody of  claim 1 . 
     
     
         20 . A method of producing a MUC1-specific antibody that binds to the intact MUC1 protein, comprising the steps of:
 i) immunizing a subject having the ability to produce antibodies with a MUC1/TM antigen including the a subunit tandem repeats in an amount sufficient to yield a MUC1-specific antibody that binds specifically to the intact MUC1 protein; and   ii) selecting for antibodies that bind to a MUC1/X antigen;   wherein the antibody does not substantially bind to either the MUC1 α subunit or the MUC1 β subunit in the absence of the other.   
     
     
         21 . The antibody of  claim 20 , wherein the antibody binds to isoform MUC1/X but does not substantially bind to isoform MUC1/Y. 
     
     
         22 . The antibody of  claim 21 , wherein the isoform MUC1/X is cleaved into a truncated α subunit and a β subunit. 
     
     
         23 . The method of  claim 20 , wherein the MUC1/TM antigen is a MUC1/TM polypeptide. 
     
     
         24 . The method of  claim 20 , wherein the MUC1/TM antigen is a nucleic acid encoding a MUC1/TM polypeptide. 
     
     
         25 . The method of  claim 20 , further comprising the step after step i) of immunizing the subject with a MUC1/X antigen. 
     
     
         26 . The method of  claim 25 , wherein the MUC1/X antigen is a MUC1/X polypeptide. 
     
     
         27 . The method of  claim 25 , wherein the MUC1/X antigen is a nucleic acid encoding a MUC1/X polypeptide. 
     
     
         28 . A method of screening for a MUC1-specific antibody that binds to an intact MUC1 protein with the proviso that the antibody does not bind to either the α-subunit or the β-subunit in the absence of the other, comprising
 i) determining the binding of a plurality of anti-MUC1 generated antibodies to a cleaved MUC1/X antigen and a MUC1/Y antigen; and   ii) selecting for antibodies that specifically bind to the MUC1/X antigen but do not significantly bind to the MUC1/Y antigen.   
     
     
         29 . A method of producing an antibody against an antigen of interest, comprising the steps of:
 i) immunizing a subject with a MUC1/TM antigen including the a subunit tandem repeats and the antigen of interest; and   ii) immunizing the subject with the antigen of interest;   whereby antibodies against the antigen of interest are produced.   
     
     
         30 . The method of  claim 29 , wherein the MUC1/TM antigen is a MUC1/TM polypeptide. 
     
     
         31 . The method of  claim 29 , wherein the MUC1/TM antigen is a nucleic acid encoding a MUC1/TM polypeptide. 
     
     
         32 . The method of  claim 29 , wherein the antigen of interest is a polypeptide. 
     
     
         33 . The method of  claim 29 , wherein the antigen of interest is a nucleic acid encoding the antigen of interest. 
     
     
         34 . The method of  claim 29 , further comprising in step i) immunizing a subject with a fusion antigen comprising MUC1/TM the antigen of interest. 
     
     
         35 . The method of  claim 29 , wherein the antigen of interest is selected from the group consisting of a human, animal, plant, bacterial, viral or synthetic antigen. 
     
     
         36 . The method of  claim 29 , wherein the antigen of interest is a tumor-associated antigen. 
     
     
         37 . The method of  claim 29 , wherein the antigen of interest is an infectious disease-associated antigen.