Interleukin 6 induces human immunodeficiency virus expression in infected monocytic cells alone and in synergy with tumor necrosis factor α by transcriptional and post-transcriptional mechanisms

The immunoregulatory cytokine interleukin 6 (1176) directly upregulates production of human immunodeficiency virus (HIV) in acutely as well as in chronically infected cells of monocytic lineage. In addition, 11,6 synergizes with tumor necrosis factor a (TNF-α) in the induction of latent HIV expression. Unlike TNF-α, upregulation ofviral expression induced by IL6 alone does not occur at the transcriptional level and it is not associated with accumulation of HIV RNA. However, when IM and TNF-α synergistically stimulate HIV production, accumulation of HIV RNA and increased transcription are observed, indicating that IM affects HIV expression at multiple (transcriptional and post-transcriptional) levels.