ANALYSIS OF VIF-DEFECTIVE HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 (HIV-1)VIRIONS SYNTHESIZED IN NON PERMISSIVE T-LYMPHOID-CELLS STABLY INFECTED WITH SELECTABLE HIV-1

In order to facilitate analyses of the molecular function of the human immunodeficiency virus type 1 (HIV-1) Vif protein, we have developed a cell culture model-system which allows permanent production of genot ypically and phenotypically vif-defective HIV-1 virions in 'non-permis sive' H9 cells. Using recombinant, replication-competent HIV-1 proviru ses coding for a selectable marker gene (gpt) instead of nef, two stab ly infected H9 subclones named M2 (vif-mutant) and WX (wild-type), res pectively, were generated. Virions released from cell line M2-displayi ng the expected vif-defective phenotype - are produced permanently, an d in an at least 50 times higher amount than virus particles from acut ely vif-negative HIV-1-infected H9 cells, Analysis of viral protein co mposition and the electron-microscopic morphology of vif-mutant virion s did not reveal any detectable differences in comparison to wild-type virions.