IL-17 expression is correlated with hepatitis B‑related liver diseases and fibrosis.

IL-17-producing T cells (Th17) have been found to play important roles in several liver diseases, but few studies have evaluated the function of such cells in hepatitis B (HBV)‑related diseases, especially in hepatic fibrosis. In this study, we examined the expression of IL‑17 in patients with different chronic HBV-related diseases, and assessed the association between IL-17 expression and the degree of fibrosis. The method of immunohistochemistry was used to evaluate the localization of intrahepatic IL-17. We demonstrated significantly increased expression of IL‑17 in HBV-related chronic liver diseases, especially in liver fibrosis, and that the level of IL-17 is strongly correlated with the degree of fibrosis. Furthermore, we found that intrahepatic IL‑17 was mainly localized in the fibrosis region. Our data reveal important roles of IL-17 and IL-17-producing cells in the progression of HBV related chronic liver diseases, especially in the formation of liver fibrosis.