Gene expression and viral prodution in latently infected, resting CD4+ T cells in viremic versus aviremic HIV-infected individuals

TW Chun, JS Justement, RA Lempicki… - Proceedings of the …, 2003 - National Acad Sciences
TW Chun, JS Justement, RA Lempicki, J Yang, G Dennis Jr, CW Hallahan, C Sanford…
Proceedings of the National Academy of Sciences, 2003National Acad Sciences
The presence of HIV-1 in latently infected, resting CD4+ T cells has been clearly
demonstrated in infected individuals; however, the extent of viral expression and the
underlying mechanisms of the persistence of HIV-1 in this viral reservoir have not been fully
delineated. Here, we show that resting CD4+ T cells from the majority of viremic patients are
capable of producing cell-free HIV-1 spontaneously ex vivo. The levels of HIV-1 released by
resting CD4+ T cells were not significantly reduced in the presence of inhibitors of cellular …
The presence of HIV-1 in latently infected, resting CD4+ T cells has been clearly demonstrated in infected individuals; however, the extent of viral expression and the underlying mechanisms of the persistence of HIV-1 in this viral reservoir have not been fully delineated. Here, we show that resting CD4+ T cells from the majority of viremic patients are capable of producing cell-free HIV-1 spontaneously ex vivo. The levels of HIV-1 released by resting CD4+ T cells were not significantly reduced in the presence of inhibitors of cellular proliferation and viral replication. However, resting CD4+ T cells from the majority of aviremic patients failed to produce virions, despite levels of HIV-1 proviral DNA and cell-associated HIV-1 RNA comparable to viremic patients. The DNA microarray analysis demonstrated that a number of genes involving transcription regulation, RNA processing and modification, and protein trafficking and vesicle transport were significantly upregulated in resting CD4+ T cells of viremic patients compared to those of aviremic patients. These results suggest that active viral replication has a significant impact on the physiologic state of resting CD4+ T cells in infected viremic patients and, in turn, allows release of HIV-1 without exogenous activation stimuli. In addition, given that no quantifiable virions were produced by the latent viral reservoir in the majority of aviremic patients despite the presence of cell-associated HIV-1 RNA, evidence for transcription of HIV-1 RNA in resting CD4+ T cells of aviremic patients should not necessarily be taken as direct evidence for ongoing viral replication during effective therapy.
National Acad Sciences