HUMAN IMMUNODEFICIENCY VIRUS-1 RECOMBINANT GP120 INDUCES CHANGES IN PROTEIN-KINASE-C ISOZYMES - A PRELIMINARY-REPORT

Human immunodeficiency virus 1 (HIV-1) and its purified proteins activate target cell functions. Because protein kinase C (PKC) plays a crucial role in signal transduction and there is a molecular heterogeneity of PKC, we compared the effect of recombinant HIV-1 gp120 and phorbol ester (PMA) on PKC isozymes in monocytic U937 cells, with isozyme-specific antibodies using now cytometry. All PKC isozymes except PKC-gamma were present in U937 cells. Both PMA and HIV-I gp120 increased levels of calcium-dependent and -independent PKC isozymes. The most striking change was observed in PKC-xi isozymes levels. This study for the first time demonstrates that HIV-1 gp120 affects calcium-independent PKC isozymes in U937 cells.