新型冠状病毒肺炎患者Mg^2+水平对CD^8+T淋巴细胞和NK细胞功能的影响

Effect of Mg level on the functions of CD8^+T lymphocytes and NK cells in patients with COVID-19

目的:探讨新型冠状病毒肺炎(COVID-19)患者血清及外周血单个核细胞(PBMCs)中Mg^2+水平变化及其对CD8^+T淋巴细胞和NK细胞功能的影响。方法:选取2020年1月20日~2月20日期间鄂州市中心医院收治的COVID-19确诊患者165例,其中轻型/普通型组98例,重型/危重型组67例,另选34例健康体检者作为对照组。采集外周血,分离PBMCs,检测各组血清及PBMCs中Mg^2+水平;流式细胞术检测各组外周血CD8^+T淋巴细胞和NK细胞亚群以及其表面抑制分子程序性死亡受体1(PD-1)和激活分子自然杀伤细胞活化受体(NKG2D)的表达水平;并分析Mg^2+水平与PD-1和NKG2D表达水平的相关性。结果:与对照组比较,轻型/普通型组和重型/危重型组患者血清及PBMCs中Mg^2+水平、CD8^+T淋巴细胞和NK细胞计数均明显降低(P<0.05),同时CD8^+T淋巴细胞和NK细胞表面抑制分子PD-1表达水平明显升高(P<0.05),而活化分子NKG2D表达水平均明显降低(P<0.05)。重型/危重型组患者以上各指标改变幅度又大于轻型/普通型组(P<0.05),且COVID-19患者Mg^2+水平与CD8^+T淋巴细胞和NK细胞表面分子PD-1表达水平呈负相关性(P<0.05),与NKG2D表达水平呈正相关性(P<0.05)。结论:COVID-19患者血清及PBMCs中Mg^2+水平会明显降低,其可能会导致CD8^+T淋巴细胞和NK细胞功能被抑制。

Objective: To investigate the changes of Mg^2+levels in serum and peripheral blood mononuclear cells(PBMCs)of patients with COVID-19 and its effects on the functions of CD8^+T lymphocytes and NK cells.Methods: A total of 165 COVID-19 patients who were diagnosed and hospitalized in Ezhou Central Hospital from January 20 to February 20,2020,and were divided into mild/common group(98 cases)and severe/critical group(67 cases).At the same time,34 healthy persons were selected as the control group.Peripheral blood was collected and PBMCs were isolated,the level of Mg^2+in serum and PBMCs was detected.The subsets of CD8^+T lymphocytes and NK cell and the expression levels of their surface inhibitory molecular PD-1 and activator molecular NKG2D were detected by flow cytometry.The correlation between Mg^2+concentration and the expression levels of PD-1 and NKG2D was also analyzed.Results: Compared with the control group,the concentration of Mg^2+in serum and PBMCs,the counts of CD8^+T lymphocytes and NK cell in patients with mild/common and severe/critical groups were significantly reduced(P<0.05),while the expression level of surface inhibitory molecular PD-1 were significantly increased(P<0.05),while the expression level of the activation molecule NKG2D were significantly decreased(P<0.05).However,the changes of the above indicators in patients with severe/critical group were greater than those in the mild/common group(P<0.05).In addition,the Mg^2+concentration in COVID-19 patients was negatively correlated with the expression level of PD-1 on CD8^+T lymphocytes and NK cells(P<0.05),and positively correlated with the expression levels of NKG2D(P<0.05).Conclusion: The concentration of Mg^2+in the serum and PBMCs of COVID-19 patients is significantly reduced,which may cause the function of CD8^+T lymphocytes and NK cells to be inhibited.