1. Th17 and Tregs at Early HIV Infection Influence Disease Progression and HIV Specific CD8+ Responses

JULIANA FALIVENE; YANINA GHIGLIONE; NATALIA LAUFER; MARÍA EUGENIA SOCIAS; MARÍA JULIA RUIZ; PEDRO CAHN; OMAR SUED; HORACIO SALOMÓN; GABRIELA TURK; MARÍA MAGDALENA GHERARDI

Boston

Conferencia; CROI 2014; 2014

Th17 and Treg subsets have been related to HIV/SIV disease progression. Their role and direct relation with specific HIV-adaptive T-cell responses during primary HIV infection (PHI) are unexplored topics. The aim of this work is to analyze the frequency and balance of Th17 and Treg subsets and the correlation with clinical parameters, immune activation and HIV-specific responses during early infection. For this PBMCs were obtained from 6 healthy donors (HDs) and 28 HIV infected subjects: 6 elite controllers (ECs), 5 chronics (Chs), and 17 PHIs (within 6 months post-infection (mpi)). Th17 and Treg cells (baseline and 8 to 14 mpi samples) were identified as CD3+/CD4+ IL-17+ or CD25+/FoxP3+ (respectively). Data was compared inter/intragroups and correlated to clinical parameters (viral load (VL), CD4 counts), CD8+ CD38+/HLA-DR+ activated T-cells and specific anti-HIV CD8+ responses (specifically a viral inhibitory activity (VIA) assay and intracellular cytokine staining (ICS) for IFN-g production and CD107a/b cytotoxicity markers) measured at baseline and 8 to 14 mpi, using parametric and nonparametric statistics. We observed that chronic patients have lower % of Th17 cells compared to HDs and ECs (p=0.004 and 0.042 respectively), among which frequencies were similar (median 0.14 vs 0.11 respectively). In PHI group, CD4 counts at 8 to 14 mpi directly correlated with baseline Th17 counts (p=0.048, r=0.5). Moreover, VL at 8 to 14 mpi inversely correlated with baseline % of Th17 (p=0.041, r=-0.596). Th17/Tregs ratio was higher for HDs compared to any HIV+ group (p