DETECTION OF SPECIFIC ANTIGEN IN SV40-TRANSFORMED CELLS BY IMMUNOFLUORESCENCE.

With an immunofluorescent technique involving the use of serum of hamsters with SV40 tumors, nuclear fluorescence was detected in each of five cell lines, derived from four mammalian species, transformed by SV40 virus. Essentially all nuclei, including those of multinuclear cells, were fluorescent-stainable. Serum of hamsters bearing SV40 tumors was also found to give nuclear fluorescence in susceptible cells (AGMK or BSC-1) acutely infected with SV40 virus. These findings provide further evidence that cellular incorporation of the SV40 viral genome, with partial expression of the genome by synthesis of at least one virus-specific antigen, is an integral property of all SV40 transformed cells.