Analysis of CD4+CD25+Foxp3+ Regulatory T Cells in HIV-Exposed Seronegative Persons and HIV-Infected Persons with Different Disease Progressions

Regulatory T cells (Tregs) are a subset of T cells that play an important role in the regulation of T-cell function. In a previous study, CD25 was used as a marker of Tregs; however, FoxP3 was recently discovered to be a valuable phenotype of Tregs. In this study, we compared the frequency of Tregs in HIV-1-infected long-term non-progressors (LTNP), AIDS patients (AP), HIV-exposed seronegative (ES) persons, and healthy controls (HC), by using CD4(+)CD25(+)FoxP3(+) as a marker of Tregs. The results showed that the frequency of Tregs in AP was significantly higher than in the LTNP, ES, and HC, which suggests that Tregs may play a role in disease progression. Another unique finding in this study is that we found a decrease of Tregs in ES.