Abortive infection of hamster embryo cells with simian virus type 15 (SV15). I. "Helper" activity for adenovirus-associated virus type 1.

Abstract

The replication of simian adenovirus (SV15) in green-monkey kidney cells (GMK) and hamster embryo cells (HE) was compared. In addition, the ability of these virus-cell systems to enhance the growth of adenovirus-associated virus type 1 (AAV-1) was studied. Simian virus 15 infectious progeny was undetectable from infected HE cells even though the cell monolayer was destroyed by viral cytopathology (CPE) similar to that observed in GMK cell cultures. Also, when SV15 was serially passed in HE cells, infectivity was undetectable after two passages. Serological analysis by complement fixation and immunofluorescent staining indicated that some SV15 antigens, which were unrelated to the viral capsid antigens, were produced in HE cell cultures. These antigens were presumably the early antigens found in adenovirus infections.Simian virus 15 productively infected GMK cells and also abortive infected HE cells were capable of enhancing AAV-1 growth. However, other known adenovirus abortive infections, e.g., adenovirus type 2 or 7 infected GMK cells, adenovirus type 12 infected or transformed HE cells, did not display "helper" activity for AAV-1 replication. The results indicate that the termination of adenovirus growth in an abortive type of infection occurs at different stages in the replication cycle, which is apparently dependent upon the virus-cell system.