In Vitro Transformation Assays Using Mouse Embryo Cell Lines

Abstract

C3H/10T1/2 C18 cells (“10T1/2”) have been employed in a variety of studies aimed at elucidation of the mechanism of cell transformation and, like 3T3 cells, have also been applied to the problem of chemical screening. This cell line was isolated from cultured C3H mouse embryo cells by Heidelberger and his colleagues (12, 13) and the 10T1/2 cells in use by various investigators can be traced directly to this laboratory. 10T1/2 cells and 3T3 cells exhibit a number of common characteristics, with the result that the assay protocols developed for the two cell lines are quite similar. For example, both cell lines are subject to post-confluence inhibition of replication (“contact inhibition”) and, in both cases, model carcinogen treatments result in the formation of foci of transformed cells superimposed on the contiguous monolayer of normal cells. As was the case for 3T3 cells, cells isolated from transformed 10T1/2 foci are transplantable. However, unlike 3T3 cells, the neoplastic potential of transformed 10T1/2 isolates appears to be linked to the degree of their initial expression of the morphologically transformed phenotype. Nonetheless, the basis for the use of 10T1/2 cells is similar to that previously described for SHE and 3T3 cells; the development of the transformed morphology is linked to the expression of cellular neoplastic qualities and therefore test material induction of the transformed phenotype is thought to be a reflection of the material’s carcinogenic potential.