Antibody-dependent cell-mediated cytotoxicity against cells infected with the human immunodeficiency virus.

Human immunodeficiency virus (HIV) elicits the production of virus-specific antibodies in infected individuals. We investigated the ability of serum from HIV-infected individuals to mediate antibody-dependent cellular cytotoxicity in an in vitro 51Cr release assay system. Fresh peripheral blood mononuclear cells from healthy donors seronegative for HIV were used as cellular effectors against HIV-infected and uninfected H9 target cells in the presence of serum from HIV-infected or uninfected donors. Serum from HIV-infected, but not uninfected, donors significantly augmented cytolysis of virus-infected targets (P less than .005). There was no augmented killing of uninfected H9 cells with sera from either group. Studies using serum from mice that had been immunized with synthetic peptides from the HIV envelope region suggested that this response is directed, at least in part, at several determinants of the transmembrane portion of the HIV envelope glycoprotein.