Transformation Assay for Murine Sarcoma Viruses Using a Simian Virus 40-Transformed Human Cell Line

Abstract

A subclone derived from a simian virus 40 (SV40)-transformed human skin fibroblast culture (SV clone 80) was susceptible to focus formation by murine sarcoma viruses (MSV). Foci were transformed within 1 week after Infection and the transformed cells were isolated and serially propagated; they continued to contain SV40 T antigen and to produce both sarcoma virus and “helper” leukemia virus. MSV pseudotypes with mouse, woolly monkey, and gibbon type-C viruses all transformed SV clone 80 cells, whereas the “helper” type-C viruses themselves did not produce transformation. Interference of focus formation by preinfection with helper virus was demonstrated.