Comparative behavior of simian virus 40 T-antigen and of tumor-specific surface and transplantation antigens during partial purification.

The simian virus 40-specific T-antigen has been extracted from SV AL/N mouse embryo tissue culture cells by treatment with Triton X-100 detergent. The extracts contained tumor-specific transplantation antigen (TSTA) and tumor-specific surface antigen. These extracts were purified by ammonium sulfate precipitation and diethyl-aminoethyl cellulose and phosphocellulose column chromatography and were assayed for the three antigens. We found that T-antigen, TSTA, and much of the tumor-specific surface antigen copurified through all purification steps. This finding is consistent with previous suggestions of the close degree of homology that must exist between the protein species carrying these three antigenic determinants. The antibody-mediated cytolytic assay appears to detect a new type of antigen on the cell surface, different from T-antigen and TSTA; two antigenic fractions were obtained from the phosphocellulose column that had tumor-specific surface antigen activity, but one of these did not have T-antigen or TSTA activities.