ENHANCED SUSCEPTIBILITY TO HUMAN-IMMUNODEFICIENCY-VIRUS INFECTION IN CD4(-LYMPHOCYTES GENETICALLY DEFICIENT IN CD43() T)

CD43 is a cell surface sialoglycoprotein expressed by most cells of he matopoietic origin, including all T lymphocytes. Elimination of CD43 e xpression by gene targeting in the CEM T cell line results in its incr eased homotypic adhesion and binding to HIV-1 gp120, Here we report th at the CD43-negative CEM cells show increased susceptibility to HIV-1 infection and increased viral replication compared with the parental C D43(+) CEM cell line. Increased HIV-1 replication also was observed in CEM cells with diminished CD43 expression secondary to functional ina ctivation of a single CD43 allele. The CD43(-) CEM cells were more sus ceptible to HIV-1-induced cytopathicity than their CD43(+) counterpart s. HIV-1 replication also was increased in the CD43(-) CEM cells after transfection with the infectious HIV molecular clone pNL4-3, These da ta suggest that factors that diminish CD43 expression on T lymphocytes may enhance their susceptibility to HIV-1 infection.