DYNAMICS AND MODULATION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 TRANSCRIPTS IN-VITRO AND IN-VIVO

The dynamics of human immunodeficiency virus type 1 (HIV-1) transcript ion was analyzed in vitro and in vivo by using a specific molecular ap proach which allows accurate quantitation of the different classes of viral mRNAs. Unspliced (US) and multiply spliced (MS) HIV-1 transcript s were assayed by competitive reverse transcription (cRT)-PCR, using a single competitor RNA bearing in tandem internally deleted sequences of both template species. Acute HIV-1 infection of primary peripheral blood mononuclear cells (PBMCs), monocytes/macrophages cells, and the A3.01 T-lymphocyte-derived cell line was studied; both classes of HIV- 1 mRNAs increased exponentially (tau(2) > 0.98) at days 1 to 3 and 1 t o 4 postinfection in HIVIIIB-infected A3.01 cells and PBMCs, respectiv ely, whereas monocytes/macrophages infected with monocytotropic HIVBaL exhibited a linear (tau(2) = 0.81 to 0.94) accumulation of US and MS transcripts. Following induction of chronically infected ACH-2 cells, MS transcripts increased 2 h postinduction and peaked at 5 h (doubling time, 58 min), while at 24 h, US mRNAs increased 3,053-fold compared with basal time (doubling time, 137 min). To address the biopathologic al significance of HIV-1 expression pattern during infection progressi on, pilot cross-sectional and longitudinal analyses were carried out w ith samples from untreated and treated HIV-1-infected patients. In alm ost all untreated (recently infected, long-term nonprogressor, and pro gressor) patients, MS transcript levels followed the general trend of systemic HIV-1 activity. In patients under treatment with powerful ant iretroviral compounds, viral MS transcripts rapidly fell to undetectab le levels, indicating that in vivo, levels of RIS mRNAs in PBMCs are c losely associated with the number of newly infected cells and suggesti ng a new role for the quantitative analysis of HIV-1 transcription in infected patients.