HIV Infection Deregulates the Balance Between Regulatory T Cells and IL-2-Producing CD4 T Cells by Decreasing the Expression of the IL-2 Receptor in Treg

JAIDS Journal of Acquired Immune Deficiency Syndromes (Impact Factor: 4.39). 12/2013; 65(3). DOI: 10.1097/QAI.0000000000000092
Source: PubMed

ABSTRACT Indexation of Treg to the number of activated T-cells constitutes a homeostatic mechanism ensuring that T-cell expansion remains under control. However, immune hyperactivation observed in HIV-infected patients suggests a possible dysfunction of this mechanism. Here we show that the Treg/IL2-producing cells balance is deeply disturbed in viremic HIV-infected patients. We found a lower expression of IL2-Rα on Treg from viremic patients. We confirmed in vitro that HIV-infection of Treg downregulates IL2-Rα and pSTAT5. Our results argue for an impaired capacity of Treg to sensing the expansion of activated T-cells in HIV-infected patients that could contribute to the immune deregulation.

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