
Regulatory T Cell Expansion and Immune Activation during Untreated HIV Type 1 Infection Are Associated with Disease Progression
Author(s) -
Weiwei Cao,
Beth D. Jamieson,
Lance E. Hultin,
Patricia M. Hultin,
Roger Detels
Publication year - 2009
Publication title -
aids research and human retroviruses
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.993
H-Index - 92
eISSN - 1931-8405
pISSN - 0889-2229
DOI - 10.1089/aid.2008.0140
Subject(s) - cd38 , immunology , foxp3 , il 2 receptor , immune system , cd8 , immunopathology , peripheral blood mononuclear cell , t cell , biology , flow cytometry , medicine , in vitro , cd34 , microbiology and biotechnology , biochemistry , stem cell
Regulatory T cells (Tregs) may play an important role in the immunopathology of chronic HIV-1 infection due to their potent suppressive activity of both T cell activation and effector function. To investigate the correlation between Tregs and immune activation during untreated chronic HIV-1 infection, we conducted a nested case-control study within the Multicenter AIDS Cohort Study (MACS). Twenty HIV-1-infected fast progressors (FP) and 40 slow progressors (SP) were included in our study using risk-set sampling. Nine age-matched HIV-1-uninfected men (UI) were also included. Cryopreserved peripheral blood mononuclear cells (PMBCs) were tested using flow cytometry analyses. We identified Tregs as Foxp3+CD25+CD4+ T cells and assessed the activation of CD4+ and CD8+ T cells by the expression of CD38, HLADR, or both markers simultaneously. There is a relative expansion of Tregs during HIV-1 infection, which is associated with disease progression. The increased CD38 expression on both CD4+ and CD8+ T cells expressed as either percentage or median fluorescence intensity (MFI) and the elevated proportion of CD8+ T cells that is HLADR+CD38+ were all associated with rapid HIV-1 progression. Counter to the assumed role of Tregs as the suppressors of activation, the expansion of Tregs was positively correlated with CD4+ T cell activation among HIV-1-infected fast progressors. The high level of Tregs associated with rapid HIV progression may suggest a detrimental role of these cells in the immune control of HIV-1 infection.