Figure 3.

Role of β-chemokines in HIV-1JR-CSF resistance in vitro exhibited by HIV-2 PBMCs. (A) PBMCs (filled squares) and the CD8-depleted fraction (open squares) derived from five individuals infected with HIV-2 were challenged with 600 TCID₅₀ of HIV-1JR-CSF, and p24 production was monitored for 14 days. (B) Antibody neutralization of RANTES, MIP-1α, and MIP-1β abrogated the HIV-2-associated resistance to R5 HIV-1 virus. Viral replication kinetics, after challenge of 250,000 resistant PBMCs derived from individuals infected with HIV-2 (n = 6) with 600 TCID₅₀ of HIV-1JR-CSF, were observed in the presence of β-chemokine-neutralizing antibodies (open diamonds) or control antibody (filled squares); median and first and third quartiles are shown. For clarity of presentation, p24 levels <50 pg/ml were assigned a value of 50 pg/ml.