Studies of human papovavirus tumor antigen in experimental and human cerebral neoplasms.

Three types of papovaviruses (JC, BK, and SV40) have been isolated from man. All three are oncogenic in hamsters, cause frequent infection of man, and share a common T antigen. Augmentation of the expression of T antigen by in vitro cultivation of SV40-induced tumors of hamsters suggested that growing human brain tumors in vitro might provide an effective screening technique for the SV40 virus. In a series of human brain tumors examined in cryostat sections and in tissue culture, T antigen could not be demonstrated, suggesting that by this immunofluorescent technique SV40 was not implicated in the etiology of these tumors.