Abstract
Objective: To study the functional effects of killer cell lectin-like receptor subfamily G member 1 (KLRG1) expression on natural killer cells (NK cell) in chronic hepatitis B virus infection (HBV). Methods: Peripheral blood mononuclear cells (PBMC) were extracted from 120 patients with chronic hepatitis B virus infection and 19 healthy persons. The frequency of NK cells and KLRG1+ NK cells in peripheral blood was detected by flow cytometry. Interferon-γ levels secreted by NK cells were detected in peripheral blood. Statistical analysis of experimental data was performed using GraphPad Prism 6.03 software. Results: The frequency of NK cells in HBV-infected group (16.92% ± 7.9%) was not significantly different from that in healthy controls (10.57% ± 6.5%). The frequency of KLRG1+NK cells in HBV-infected group was significantly higher (49.43% ± 21.2%) than that to healthy control group (31.60% ± 17.9%), (t = 7.347 6, P < 0.001). IFN-γ secretion of KLRG1 + NK cells in HBV-infected patients (2.59% ± 1.0%) were significantly lower than healthy controls (5.96% ± 2.4%), (P = 0.009). Conclusion: HBV infection can increase the expression of KLRG1 in NK cells and further reduce the secretion of IFN-γ in NK cells, which may be an important cause for chronic HBV infection.