Infectious primate type C virus proviral DNA in productively infected cells.

Cell lines competent to infection by DNA from cultures chronically infected by type C viruses of the simian sarcoma virus and baboon endogenous virus groups were identified. Significant differences were observed in the relative susceptibility of some cell lines to infection by a given proviral DNA. Practical applications of transfection techniques for the separation of viruses from dually infected cultures and to free virus stocks from mycoplasmal contamination are described.