CD4+ T lymphocytes from different donors vary in their ability to replicate different isolates of HIV. β-chemokines have been shown to reduce the rate of HIV replication in cultured cells. We now demonstrate, using CD4+ cells from 19 different donors, that the variations in viral replication observed in CD4+ lymphocytes are not due to endogenous production of β-chemokines by the cells. Instead of finding a correlation of high-level β-chemokine production with low-level replication of virus, we found either no consistent relationship between these two parameters or a correlation between high-level β-chemokine production and high-level virus replication. This observation was made with both chemokine-sensitive and chemokine-resistant HIV isolates. Thus, other mechanisms appear to be involved in the variability in HIV replication in cultured CD4+ cells.