Cytopathic effects of non-syncytium-inducing and syncytium-inducing human immunodeficiency virus type 1 variants on different CD4+T-cell subsets are determined only by coreceptor expression

In peripheral blood mononuclear cells, syncytium-inducing (SI) human immunodeficiency virus type 1 (HIV-1) infected and depleted all CD4(+) T cells, including naive T cells. Non-SI HIV-1 infected and depleted only the CCR5-expressing T-cell subset. This may explain the accelerated CD4 cell loss after SI conversion in vivo.