Lack of evidence for complete resistance of peripheral blood mononuclear cells to HIV-1 and HIV-2 infection.

There are reports that not all individuals exposed to HIV-1 become infected and the possibility exists that some individuals may be completely resistant to infection with this virus. This study aims to investigate, in vitro, whether certain peripheral blood mononuclear cells (PBMCs) are completely resistant to HIV-1 and HIV-2 infection. PBMCs obtained from 130 unrelated healthy HIV-1– and HIV-2–seronegative volunteers were infected with four different isolates of HIV-1 (H995 and MN) and HIV-2 (CBL-20 and ROD) using several multiplicities of infection. Cultures were maintained for 21 d. Virus replication was measured using the viral p24 core antigen levels in the case of HIV-1, and by reverse transcriptase (RT) activity in the case of HIV-2, at 5, 14, and 21 d post-infection. Marked variations were observed among PBMCs from individual donors with regard to replication rates for HIV-1 and HIV-2. None of the PBMCs from any single donor was shown to have zero viral replication rates for all four HIV isolates ...