Effects of the Treg/Th17 cell balance and their associated cytokines in patients with hepatitis B infection

The extent to which T-cell-mediated immunity is impaired in patients with hepatitis B virus (HBV) infection remains controversial. In addition, the role of T regulatory (Treg) and T helper 17 (Th17) cells and their associated cytokines in immunity is not clear. In the present study, peripheral blood samples were collected from 44 patients with chronic hepatitis B virus, 14 asymptomatic hepatitis B carriers, 19 patients with liver cirrhosis and 20 healthy individuals. Flow cytometry was used to detect the percentages of T cell subsets in the samples, including CD3⁺, CD4⁺ and CD8⁺ T cells, Treg cells and Th17 cells. A cytometric bead array was conducted to detect the levels of interleukin (IL)-17, -6, -10 and -21, and transforming growth factor (TGF)-β. The data revealed that Treg cell levels decreased, while Th17 cell levels increased in the peripheral blood of HBV patients. As the extent of inflammation and fibrosis in the hepatic tissue increased, the frequency of Treg and Th17 cells in the peripheral blood did not significantly differ. In addition, the levels of Th17 cells were found to positively correlate with TGF-β and IL-21 levels. Therefore, analyzing the balance between Treg/Th17 cells and their associated cytokines may be a useful indicator in the diagnosis of HBV.