CD4+ and CD8+ Regulatory T Cells (Tregs) are Elevated and Display an Active Phenotype in Patients with Chronic HCV Mono-Infection and HIV/HCV Co-Infection

The aim of this study was to examine regulatory T cells (Tregs) in peripheral blood and liver tissue in patients with chronic hepatitis C virus (HCV) mono‐infection and in patients with HIV/HCV co‐infection. In a cross‐sectional study were included 51 patients with chronic HCV infection, 24 patients with HIV/HCV co‐infection and 24 healthy individuals. CD4+ and CD8+ Tregs were determined using flow cytometry. Fibrosis was examined by transient elastography. Inflammation, fibrosis and Tregs were determined in liver biopsies from 12 patients. Increased frequency of CD4+ and CD8+ Tregs was found in HIV/HCV co‐infected patients [median: 6.4% (IQR: 5.7–6.9) and 1.0% (0.7–1.2), respectively] compared to HCV mono‐infected patients [5.6% (4.2–6.3), P = 0.01 and 0.5% (0.3–0.7), P