A comparison of human papovavirus T antigens.
A comparison was made of the T antigens induced in transformed cells or infected permissive cells by representatives of three categories of human papovavirus. The transformed hamster cell lines employed contained T antigen induced by either the BK or RF strains of papovavirus associated with human renal allografts; the JC strain of papovavirus from progressive multifocal leukoencephalopathy (PML), or a variant of SV40 virus isolated from PML. The human papovavirus T antigens were also compared with that of a human cell line transformed by SV40 of simian origin. Anti-T antibody prepared in hamsters against each of the hamster cell lines was absorbed with crude T antigen from each cell line, and the unabsorbed and absorbed antisera were tested for residual T antibody against each cell line, or against infected permissive cells by immunoperoxidase (IP) staining and complement-fixation (CF) tests. In unabsorbed antisera, T antibodies from each cell line cross-reacted with all T antigens in IP tests, and CF tests showed that T antisera reacted preferentially with T antigen induced by homologous virus. Absorpminants. T antigens of the two urine-derived strains, BK and RF, were identical or nearly so, but were clearly separable from T antigens of JC virus, PML-derived SV40 or simian-derived SV40. JC T antigen was intermediate, being more closely related to T antigens both of BK virus and SV40 virus than the latter were to each other. The T antigen of PML-derived SV40 could be distinguished from the T antigen of simian-derived SV40 and the T antigen of the SV40 variant from human brain was more closely related to those of the other human-derived papovaviruses than was the T antigen of SV40 from monkey kidney.