IL-10 cooperates with TNF-alpha to activate HIV-1 from latently and acutely infected cells of monocyte/macrophage lineage.
IL-10 is elevated in HIV-1-infected individuals and has been implicated in disease progression. In this study, we investigated the effects of IL-10 on the activation of HIV-1 from infected monocytes and macrophages. Although IL-10 alone did not induce HIV-1 replication, in the presence of TNF-alpha, IL-10 markedly enhanced virion production from a chronically infected promonocytic cell line (U1) and in acutely infected monocyte-derived macrophages. Neutralizing mAbs to IL-10 and TNF-alpha indicated that both cytokines were essential for the induction and were required to generate a synergistic increase in virus expression. The effects of the two cytokines were distinguishable functionally since pretreatment with TNF-alpha attenuated the cytokine cooperativity, while pretreatment with IL-10 potentiated their cooperativity, suggesting that IL-10 and TNF-alpha play different roles in the activation of virus. Northern blot analysis as well as Ab blocking and cytokine secretion studies indicated that the induction of either endogenous TNF-alpha or IL-10 was not involved in the cooperativity, nor was an up-regulation of TNF-alpha receptors. In combination with TNF-alpha, IL-10 stimulated activating protein-1 (AP-1) and nuclear factor (NF)-kappa B binding activities and cooperated to increase HIV-1 steady-state mRNA levels and enhance long terminal repeat-directed transcription through activation of the NF-kappa B binding sites, suggesting the IL-10 effect occurs at least in part at the transcriptional level. These results indicate that IL-10, in addition to down-regulating the cellular immune response to HIV-1, may also play a role in TNF-alpha-mediated activation of HIV-1 replication in the monocyte/macrophage lineage.
Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA.
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A
Finnegan
K A
KA
Roebuck
B E
BE
Nakai
D S
DS
Gu
M F
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Rabbi
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Song
A L
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Landay
D001483:Base Sequence; D004357:Drug Synergism; D015967:Gene Expression Regulation, Viral / Q000187:drug effects*; D016325:HIV Long Terminal Repeat; D015497:HIV-1 / Q000187:drug effects / Q000254:growth & development*; D006801:Humans; D016753:Interleukin-10 / Q000494:pharmacology*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology; D008264:Macrophages / Q000821:virology*; D008969:Molecular Sequence Data; D009000:Monocytes / Q000821:virology*; D016328:NF-kappa B / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D012367:RNA, Viral / Q000096:biosynthesis; D011993:Recombinant Fusion Proteins / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014775:Virus Activation / Q000187:drug effects*; D017735:Virus Latency; D014779:Virus Replication
D016328:NF-kappa B; D012333:RNA, Messenger; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10