Detection of human immunodeficiency virus type 1 after infection of unstimulated peripheral blood mononuclear cells

Application of a highly sensitive PCR-based reverse transcriptase (RT) assa y to the analysis of the infection of CD4(+) cell lines with human immunode ficiency virus type 1 (HIV-1) demonstrated that virus production can be det ected as early as 24 h after infection. Most of the signal at 24 h was due to virus production, as it could be substantially reduced by prior treatmen t with the RT inhibitor zidovudine. Virus production at 24 and 48 h was una ffected by the protease inhibitor indinavir. Infection of unstimulated peri pheral blood mononuclear cells (PBMC) with a macrophage-tropic HIV-1 isolat e yielded increasing virus production for 2-3 weeks, while infection with a T-cell line-tropic isolate yielded only low and sporadic virus production. Productive infection of unstimulated PBMC by the macrophage-tropic virus r equired functional Gag matrix and Vpr proteins; therefore, the monocyte-der ived macrophage is probably the virus-producing cell in these cultures.