Siglec-7^＋自然杀伤细胞频数下降与乙型肝炎病毒相关肝硬化疾病进展相关

Reduced frequency of natural killer cell on siglec-7^＋ is associated with progression of hepatitis B virusrelated cirrhosis

目的探索自然杀伤（NK）细胞上Siglec-7分子（唾液酸结合免疫球蛋白样凝集素7）与乙型肝炎病毒相关肝硬化之间的关系。方法收集HBV相关肝硬化患者外周血资料31例（Child—PughA级7例，Child—PughB级12例，Child—PughC级12例）以及健康对照外周血23例。通过密度梯度离心法获取外周血单个核细胞，通过流式细胞术检测NK细胞及其亚群上的Siglec-7分子及细胞表型。计量资料采用t检验、单因素方差分析。用Pearson相关系数分析变量之间的相关性。结果（1）HBV相关肝硬化患者外周血NK细胞及其亚群数量和健康对照相比差异无统计学意义。（2）与健康对照（75．39％±12．19％）相比，HBV相关肝硬化患者Siglec-7^＋NK细胞频数（62．44％±13．45％）下降。其中，Child—Pugh C级患者（61．13％±12．07％）下降最为明显。Siglec-7^＋NK细胞频数与Child—Pugh评分呈负相关。（3）亚群分析显示HBV相关肝硬化患者Siglec-7^＋CD56^brightCD16-NK细胞频数（66．99％±15．93％）显著低于Siglec-7^＋CD56^dimCD16^＋NK细胞（76．54％±13．90％），健康对照中Siglec-7在两组NK细胞亚群中表达差异无统计学意义。（4）表型分析结果显示，Siglec-7^＋NK细胞表达更高水平的活化性受体CD16、CD38、NKp46和较低水平的抑制性受体CD158b。HBV相关肝硬化患者Siglec-7^＋NK细胞表达CD16、CD38频数低于健康对照组。结论HBV相关肝硬化患者外周血Siglec-7^＋NK细胞频数下降，并与疾病进展相关。

Objective To explore the relationship between sialic-acid-binding immunoglobulin-like lectin 7 （Siglec-7） expressed on NK cells and hepatitis B virus-related cirrhosis. Methods Peripheral venous blood samples were collected from 23 healthy controls and 31 patients with hepatitis B virus-related cirrhosis （Child-Pugh A,n = 7; Child-Pugh B,n = 12; Child-Pugh C,n = 12）. Peripheral blood mononuclear cells （PBMCs） were obtained by using Ficoll-Hypaque density gradient centrifugation and the expression of Siglec-7 and NK cells phenotype and their subpopulations were detected by flow cytometry. Comparisons between various groups were performed using t -test, one-way analysis of variance （ANOVA）, and correlations between variables were analyzed using Pearson＇s-correlation coefficient. Results （1） There was no significant difference in the percentage of NK cells and in their subpopulations with HBV-related cirrhosis and healthy controls. （2） Siglec-7 expression on NK cells in patients with HBV-related cirrhosis（62.44±13.45%）was significantly down-regulated than that to healthy controls（75.39±12.19%）while the fi＇equency of Siglec-7^＋ NK cells were negatively correlated with Child-Pugh score. （3） Subpopulation analysis showed that Siglec-7 expression on CD56^bnghtCD16NK cells（66.99±15.93%）was significantly lower than CD56^dimcD16＋NK cells（76.54±13.9%） in HBV-related cirrhosis. However, the expression of Siglec-7 in healthy controls showed no difference in these two NK cell subsets. （4） Phenotypic analysis showed that Siglec-7^＋ NK cells express higher levels of activating receptor CD16, CD38, NKp46 and lower levels of inhibitory receptor CD158b. Indeed, the frequency of CD16 and CD38 on Siglec-T NK cells in HBV-related cirrhosis was lower than that in healthy controls. Conclusion The disease progression in patients with hepatitis B virus-related cirrhosis is associated to decreased frequencies of Siglec- 7^＋NK cells.