T-cell exhaustion in HIV-1/hepatitis C virus coinfection is reduced after successful treatment of chronic hepatitis. Open Forum Infectious Diseases
Caraballo Cortés et al. Caraballo Cortés et al. investigated immune exhaustion markers in individuals with HIV and hepatitis C virus (HCV) coinfection before and after HCV treatment, comparing these to markers in individuals with HCV monoinfection. The study involved 31 participants with HIV/HCV coinfection from the Swiss HIV Cohort Study, all undergoing antiretroviral therapy, and 45 individuals with HCV monoinfection from the Warsaw Hospital for Infectious Diseases. Key markers analyzed included PD-1, Tim-3, and IL-10, measured in plasma and peripheral blood mononuclear cell (PBMC) samples prior to and approximately one year after PEG-interferon based HCV treatment.
The results showed that before HCV treatment, individuals with coinfection had higher levels of soluble PD-1 and IL-10 compared to those with HCV alone, and these levels decreased after successful HCV treatment. Soluble Tim-3 levels were similar between both groups and also decreased post-treatment. In PBMCs, individuals with coinfection had lower PD-1 mRNA levels and higher IL-10 mRNA levels compared to the group with HCV monoinfection, with no significant change post-treatment except for a decrease in Tim-3 mRNA levels.
In summary, the findings indicate a greater immune exhaustion in individuals with HIV/HCV coinfection, evidenced by higher sPD-1 and IL-10 levels in plasma, and higher IL-10 mRNA in PBMCs. The study also highlights the beneficial effect of HCV treatment in reducing immune exhaustion markers, underlining the importance of eliminating HCV antigen load. Further studies are needed to evaluate the changes in immune exhaustion after the contemporary HCV treatments using direct-acting antivirals.