ACCUMULATION OF UNINTEGRATED VIRAL-DNA IN RAT GLIAL-CELLS INFECTED WITH NEUROTROPIC FRIEND MURINE LEUKEMIA-VIRUS

FrC6 virus isolated from Friend murine leukemia virus (FLV) as a neuro tropic virus clone induced a high-degree of accumulation of unintegrat ed viral DNA during infection of rat glial cells by 72 h post-infectio n. When anti-FLV neutralizing antibody, dextran sulfate, or 3'-azido-3 '-deoxythymidine (AZT) was added to the culture within 24 h after infe ction, the accumulation of unintegrated viral DNA was inhibited. Howev er, after 30-36 h post-infection, addition of anti-FLV antibody or dex tran sulfate scarcely inhibited the accumulation of the unintegrated v iral DNA, while addition of AZT at 30-36 h post-infection still reduce d the amount of unintegrated viral DNA. Our results demonstrate that a fter 30-36 h post-infection, when second-round infection had already t aken place, further superinfection with cell-free virus to glial cells was not required for the accumulation of unintegrated viral DNA. Poss ible mechanisms are discussed.