Antibodies to a surface membrane marker from human mammary carcinoma cell line.
A tumor surface antigen (BTA-BT20-68K) was isolated from a human mammary carcinoma cell line (BT-20). The antigen (Mr 68,000) induced the formation of high titer antibodies which recognized BTA-BT20-68K as a cell surface marker by the immune adherence hemagglutination test and recognized the soluble antigen by solid phase radioimmunoassay. The antibodies which failed to recognize human beta-2-microglobulin, alpha-fetoprotein, and carcinoembryonic antigen were cytotoxic to the parent BT-20 tumor cells at high serum dilutions. The antibodies recognized a similar tumor surface marker isolated directly from human breast adenocarcinomas, but failed to recognize human lymphocyte antigens isolated from BT-20 cells or bound to human lymphocytes bearing human lymphocyte antigen markers in common with those of BT-20 cells. Added to BT-20 tumor cells in culture and in the absence of complement, antibody-dose-related inhibition of tumor cell growth was documented. In the presence of complement, the antibodies were highly cytotoxic to the parent cells. These results demonstrate the presence of a unique tumor surface marker with chemical and immunological properties in common with that isolated directly from human breast adenocarcinomas.
D000230:Adenocarcinoma / Q000276:immunology; D000912:Antibodies, Neoplasm / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D000954:Antigens, Surface / Q000032:analysis*; D001943:Breast Neoplasms / Q000276:immunology*; D002448:Cell Adhesion; D002455:Cell Division; D002460:Cell Line; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008970:Molecular Weight
D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D000954:Antigens, Surface