Preliminary study of the Th17/Treg immunoregulation in patients coinfected with TB and HIV before and after HAART]

To study the Th17/Treg (regulatory T cells) immunoregulation in patients coinfected with TB and HIV before and after HAART(highly active anti-retroviral therapy).10 HIV cases coinfected with TB (HIV/TB group) and 10 cases infected with HIV only (HIV group) received HAART. PBMCs were stained and immunophenotyping of Th17 (IL-17 expressing T cells) and CD4+ CD25 T cells (Treg) were analysed by flow cytometry.The pre-treatment patients tended to have lower Th17 cells and higher Tregs cells compared to post-treatment (1.90% +/- 0.9% vs. 4.65% +/- 1.48%, 16.48% +/- 4.91% vs. 8.29% +/- 3.13% respectively). The percentage of IL-17 before and after HAART were 1.90 +/- 0.9% vs. 4.65 +/- 1.48% respectively in HIV/TB group patients (P < 0.01). The difference between the percentage of IL-17 before and after HAART in the HIV/TB group and the HIV group were 2. 65 +/- 1.62% vs. 0.67% +/- 0.46% respectively (P < 0.01). IL-17 expressing T cells were increased faster after HAART in the former group than the latter. The percentage of Treg before and after HAART were 16.48% +/- 4.91% vs. 8.29% +/- 3.13% respectively in HIV/TB group (P < 0.01). The difference between the percentage of Treg before and after HAART in the HIV/TB group and the HIV group were 8.91% +/- 4.82% vs. 2.63% +/- 2.34% respectively (P < 0.01). Treg were decreased more rapidly after HAART in the former than the latter.TB and HAART both had an effect on the Th17/Treg ratio of HIV/ TB co-infected patients, which can cause increased Th17 expression, the later plays a pro-inflammatory role. TB and HAART can decrease Treg expression and enhance anti-inflammation response. The fact that Th17/ Treg disorder are more likely to exist in patients with HIV/TB co-infection after HAART for one month suggests a potential role for Th17/Treg imbalance leading to tuberculosis-associated immune reconstitution inflammatory syndrome during patients receiving HAART period.