Residual cell-associated unspliced HIV-1 RNA in peripheral blood of patients on potent antiretroviral therapy represents intracellular transcripts.
Unspliced HIV-RNA (HIV-UsRNA) associated with peripheral blood mononuclear cells (PBMCs) persists in patients on potent antiretroviral therapy even in the absence of detectable plasma HIV-RNA. To further characterize such residual HIV-RNA, cell-associated virion-encapsidated HIV and intracellular unspliced HIV-RNA were differentiated and monitored using a novel highly sensitive method. In addition, expression of HIV-mRNA encoding tat and rev was assessed. PBMCs of patients with unsuppressed plasma viraemia harboured an extracellular fraction of HIV-UsRNA, which correlated highly with intracellular HIV-RNA levels. Thus, extracellular PBMC-associated HIV-RNA may, to a significant extent, reflect nascent virions attached to productively infected cells. Upon treatment with potent antiretroviral therapy resulting in plasma viraemia <50 copies/ml, expression of cell-associated viral particles was hardly discernible in PBMCs but transcription of unspliced HIV-RNA persisted. Given the virtual absence of rev-mRNA, translation of residual HIV-UsRNA was probably precluded by retention of these transcripts in the nucleus. As shown by limiting dilution analysis, HIV-1 infected cells with such a repressed viral transcription pattern were observed at high frequencies in PBMC from untreated patients.
Fischer
Marek
M
Department of Medicine, University Hospital Zürich, Switzerland. marek.fischer@dim.usz.ch
Wong
Joseph K
JK
Russenberger
Doris
D
Joos
Beda
B
Opravil
Milos
M
Hirschel
Bernhard
B
Trkola
Alexandra
A
Kuster
Herbert
H
Weber
Rainer
R
Günthard
Huldrych F
HF
D019380:Anti-HIV Agents / Q000627:therapeutic use*; D002460:Cell Line; D015331:Cohort Studies; D015757:Genes, rev; D015756:Genes, tat; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000821:virology*; D012333:RNA, Messenger / Q000032:analysis; D012367:RNA, Viral / Q000097:blood*
D019380:Anti-HIV Agents; D012333:RNA, Messenger; D012367:RNA, Viral