Maraviroc contributes to the restoration of the homeostasis of regulatory T-cell subsets in antiretroviral-naive HIV-infected subjects.

Regulatory T (Treg) cells comprise different functional subsets with different CCR5 expression. Treg homeostasis is disrupted by HIV but the effect of treatment has barely been explored. In a longitudinal design, we compared the effect of a maraviroc-containing (n = 9) or sparing (n = 12) therapy in antiretroviral-naive HIV-positive participants on peripheral FoxP3(low) CD45RA(+) (nTreg), FoxP3(high) CD45RA(-) (eTreg) and FoxP3(low) CD45RA(-) (non-Treg) cells. Maraviroc significantly reduced all subsets in the short-term and, except for nTreg cells, also normalized them in the long-term. The correlation between eTreg cells and CD4 counts, lost before treatment, was only restored by maraviroc. The differential effect of maraviroc on Treg subsets contributes to understanding its immunomodulatory effects.