GENERATION OF MONOCLONAL-ANTIBODIES REACTING WITH NORMAL AND CANCER-CELLS OF HUMAN-BREAST

Abstract

From the fusion of the murine myeloma P3- X63-Ag8-U1 with spleen cells from a mouse immunized with the human breast cancer cell line MCF-7, 88 hybridomas producing antibodies reacting with the immunizing cells were obtained. After a first screening on human leukocytes, red blood cells and platelets, and on human and fetal calf serum, 3 monoclonal antibodies (MBr1, MBr2, and MBr3) with specificity for the immunizing cells were isolated and further characterized. The 3 monoclonals were tested by isotopic antiglobulin assay and immunofluorescence on a panel of normal cells or cell membrane preparations, including milk epithelial and foam cells; on plasma and milk proteins; on cells or cell membrane preparations from fresh surgical specimens of breast, kidney, and ovarian carcinomas; and on various tumor cell lines. MBr1 and MBr2 had a superimposable reactivity and showed specificity for a structure which seems to characterize both normal and neoplastic mammary gland epithelial cells.