1974 Articles

The Stable Classes of Transformed Cells Induced by SV40 Infection of Established 3T3 Cells and Primary Rat Embryonic Cells

Risser, R.; Rifkin, D.; Pollack, Robert

Previous studies have suggested that several distinct patterns of transformed behavior may result from in vitro infection by SV40 (Black 1966; Smith et al. 1971). We have systematically investigated the transformation of two kinds of mammalian cells by SV40. In doing this we have applied several assays of in vitro growth control to randomly picked clones of cells arising after SV40 infection. In this study both highly susceptible heteroploid 3T3 mouse fibroblasts and diploid cultures of embryonic rat cells have been used. The latter cells have the advantage of allowing one to monitor establishment into cell lines as well as morphological transformation (Hayflick and Moorhead 1961).

The data presented in this paper demonstrate that clear differences are seen in the classes of transformed cells induced by infection of the established or primary cultures. Furthermore, both cell cultures give rise to transformants which express only some of the changes of in vitro growth properties commonly associated with SV40 transformation.