Ètude du mècanisme de l'induction chez des cellules de hamster syrien transformèes par le virus SV40 I. Propriètès d'une lignèe cellulaire clonale

Abstract

Abstract A clonal cell line (clone 2 TSV‐5) has been derived from a primary SV40 Syrian hamster turmor. Association of clone 2 TSV‐5 cells to kidney cells of some animal species (Cercopithecus monkey, Rhesus monkey, Man) allows to recover infectious SV40 virus from the mixed cultures. This phenomenon can be considered an induction phenomenon. The clone 2 TSV‐5 is characterized by a mean frequency of induction by association of 6%, but the SV40 genome is entirely present in all these clonal cells. The induced SV40 virus is similar to the SV40 virus by which the clone 2 TSV‐5 cells have been originally converted. The clone 2 TSV‐5 is not inducible by rabbit kidney cells, by mouse embryo cells or by human KB cells. It is neither inducible by × or ultraviolet irradiations, nor by several chemical agents, such as mitomycin C, proflavine and hydrogen peroxide. Three other Syrian hamster cell lines converted by SV40 virus are not inducible by Cercopithecus monkey kidney cells. It is assumed that these malignant cells contain only a portion of the viral genome.