慢性乙型肝炎患者外周血NK细胞杀伤细胞凝集素样受体G1表达及其对NK细胞杀伤功能的影响*

目的 探讨CHB患者外周血NK细胞杀伤细胞凝集素样受体亚家族G成员1(KLRG1)表达的变化以及其对NK细胞杀伤功能的影响。方法 在120例CHB患者和120例健康体检者,抽取外周血,提取外周血单个核细胞,使用流式细胞仪检测NK细胞、KLRG1⁺ NK细胞和分泌γ-干扰素的NK细胞百分率,体外检测NK细胞对LX-2细胞的杀伤力。结果 CHB患者外周血NK细胞百分率为(17.2±7.7)%,显著高于对照组 (11.3±6.9)%,t=9.85,P=0.01】, KLRG1⁺NK细胞百分率为(52.2±20.3)%,显著高于对照组 【(30.3±16.9)%,t=6.57,P=0.01】,分泌IFN-γ的NK细胞百分率为(14.6±3.8)%,显著低于对照组【(42.5±9.5)%,t=11.24,P=0.01】;CHB患者外周血NK细胞CD38、CD69、HLA-DR和TRAIL表达均显著高于对照组(P=0.012,P=0.015,P=0.025,P=0.019);CHB患者NK细胞诱导LX-2细胞发生早期凋亡率为11.5% (6.6%～13.7%),晚期凋亡率为7.2% (5.1%～8.5%),与对照组的15.4% (11.5%～24.3%)和13.5% (8.1%～20.4%) 比,显著降低 (U=6.50, P=0.025;U=2.02,P=0.002) 。结论 CHB患者NK细胞表达KLRG1增强,通过减少分泌INF-γ而导致其杀伤功能减弱,可能系造成慢性感染的重要原因。

Intensified expression of lectin-like receptor G1 in natural killer cells of patients with chronic hepatitis B

Objective The aim of this study was to investigate the expression of lectin-like receptor G1(KLRG1)in natural killer cells of patients with chronic hepatitis B(CHB).Methods 120 patients with CHB and 120 healthy persons were included in this study,and the percentage of NK cells,KLRG1+NK cells and interferon-γsecreting NK cells from peripheral blood mononuclear cells(PBMCs)were detected by flow cytometry,and the cytotoxicity of NK cells toLX-2 cells was also assayed.Results The percentage of NK cells in peripheral blood of patients with CHB was(17.2±7.7)%,significantly higher than(11.3±6.9)%,t=9.85,P=0.01],the percentage of KLRG1+NK cells was(52.2±20.3)%,much higher than(30.3±16.9)%,t=6.57,P=0.01]and the percentage of interferon-γsecreting NK cells was(14.6±3.8)%,significantly lower than(42.5±9.5)%,t=11.24,P=0.01]in the control;the expression of CD38,CD69,HLA-DR and TRAIL in NK cells in patients with CHB intensified greatly as compared to those in control(P=0.012,P=0.015,P=0.025,P=0.019);the early apoptosis rate of LX-2 cells in patients with CHB was 11.5%(6.6%-13.7%),and the late apoptosis rate was 7.2%(5.1%-8.5%),decreased greatly as compared to 15.4%(11.5%-24.3%)or 13.5%(8.1%-20.4%)in the control(U=6.50,P=0.025;U=2.02,P=0.002).Conclusion The expression of KLRG1 in NK cells in patients with CHB intensifies,and the reduced secretion of INF-gamma might decrease the immune functions and lead to chronic infections.