The Role of T Helper 17 (Th17) and Regulatory T Cells (Treg) in the Pathogenesis of Vulvovaginal Candidiasis among HIV-Infected Women

Abstract

Background. The study sought to describe relationships between 20 cytokines and chemokines (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, G-CSF, GM-CSF, IFN-γ, MCP-1, MIP-1β, TNF-α, TGF-β1, TGF-β2, and TGF-β3) and the presence of vulvovaginal candidiasis (VVC) in women, stratified by HIV status. Methods. Plasma and genital samples were obtained from 51 clinic attendees in KwaZulu-Natal between June 2011 and December 2011. Cytokine and chemokine concentrations were measured by Luminex® multiplex immunoassays. Multiple comparisons of means of cytokine/chemokine levels displaying significant differences in univariate analyses across the study groups were performed using post hoc Bonferroni pairwise tests considering a type I error rate of 0.05. A discriminant analysis (DA) was carried out to identify linear combinations of variates that would maximally discriminate group memberships. Results. Of the 51 participants, 16/26 HIV-infected and 15/25 HIV-uninfected women were diagnosed with VVC. DA identified 2 variables (MIP-1β and TGF-β3) in plasma (Box’s M (5.49), $p$ (0.57) > α (0.001); Wilks’ lambda = 0.116, $p<0.0001$ ) and 1 variable (IL-13) in vaginal secretions (Box’s M (2.063), $p$ (0.37) > α (0.001); Wilks’ lambda = .677, $p<0.0001$ ) as able to discriminate the HIV + VVC + group, whilst TGF-β1 in plasma discriminated the HIV + VVC − group. Mean concentrations of genital IL-6, IL-8, IL-10, IL-17, and TGF-β3 were significantly higher in HIV infected women coinfected with VVC. Conclusions. In HIV-infected women, VVC might be explained by a decline of Th17 cells, hence a decrease of Th17/Treg ratio.