HLA-DR expression on regulatory T cells is closely associated with the global immune activation in HIV-1 infected subjects naïve to antiretroviral therapy.

Background: The frequencies of regulatory T cells (Tregs) increased over the HIV infection but its counts actually decreased. We proposed that the decrease of Treg counts may cause the reduction of inhibitory effect and thereby account for the over-activation of Tregs during HIV infection. However, it remains unknown whether Tregs are also over-activated and thereafter the activation induced death may lead to the decrease of Tregs.

[Association of PD-1 expression on CD4+ CD25 nt/hi CD127 lo regulatory T cells with disease progression in HIV-1 infected patients].

Aim: To investigate whether Programmed death-1 (PD-1) expression on peripheral CD4(+)CD25(nt/hi)CD127(lo) regulatory T cells (Treg) was associated with disease progression in HIV-1-infected patients.

Methods: Peripheral blood from 108 HIV-1-infected patients in distinct disease progression statuses and 27 healthy individuals were collected in the present investigation. PBMCs were isolated by centrifugation on Ficoll-Hypaque, followed by staining with anti-CD4-PerCP, anti-CD25-FITC, anti-CD127-PE and anti-PD-1-APC.