Background and aims: Th17 cells have been shown to mediate host defensive mechanisms in various infections, but their role in HBV infection in humans has not been well characterized. In this study, we analyzed the frequency and cytokines secretion of circulating Th17 cells in HBV infected patients with different statuses, and also evaluated the potential association of Th17 frequency with the levels of liver injury.
Methods: The study population consisted of 133 subjects, including 40 mild chronic hepatitis B (CHB) patients, 37 severe CHB patients, 20 acute hepatitis B (AHB) patients and 36 healthy controls. The frequency of circulating Th17 cells were carried out by intracellular cytokine staining analysis and serum IL-10 levels were measured by ELISA.
Results: Our data shown that AHB and severe CHB patients had a significant increase of Th17 cells frequency in peripheral blood compared with mild CHB patients and healthy control (both P < 0.05). The elevated prevalence of Th17 cells is positively associated with the increased serum ALT levels in severe CHB patients (r= 0.457, P= 0.004) but had no correlation with serum HBV DNA load. In addition, the serum IL-10 were negatively correlated with the frequency of Th17 cells in PBMC from patients with chronic HBV infection (r=-0.452, P < 0.01).
Conclusion: Th17 cells may contribute to the disease progression and pathogenesis of liver injury in HBV infected patients, and the induction of IL-10 may be one mechanism of constraining pro-inflammatory Th17 responses.