Cell surface antigens of chemically induced fibrosarcomas: Detection by a monoclonal antibody of a tumor-restricted M sub(r) 12,000 protein gag antigen encoded by a dual-tropic murine leukemia virus

Fusion products of spleen cells of W/FuDp rats immunized with a methylcholanthrene-induced BALB/c sarcoma, CA-2, and mouse myeloma cells were screened in an attempt to identify a monoclonal antibody defining the individually distinct tumor-specific transplantation antigen of CA-2. A hybridoma, MP/69/04, was isolated which produces an IgG sub(2a) monoclonal antibody that recognized a tumor-restricted antigen of CA-2. In direct binding assay, MP/69/04 reacted only with 2 of 15 methylcholanthrene induced BALB/c sarcomas tested. Thymus, spleen, lymph nodes, bone marrow, brain, adult lung fibroblasts, newborn muscle fibroblasts and 3T3 cells were negative.