活动期肺结核患者外周血miR-29a的表达及其临床意义

The expression and clinical significance of miR-29a in peripheral blood of patients with active pulmonary tuberculosis

目的分析活动期肺结核患者外周血miR-29a的表达情况及其临床意义。方法收集2015年1月至2016年12月绍兴市立医院诊断的45例未经抗结核治疗的活动性肺结核患者(活动组),45例其他肺部疾患者(其他肺疾病组)和45例健康体检者(健康对照组)的外周血,通过实时定量PCR技术检测各组研究对象血清中miR-29a的表达水平并进行ROC曲线分析。采用ELISA法检测各组研究对象血清IFN-γ表达水平;采用流式细胞术测定各组研究对象外周血T细胞亚群水平。分析活动性结核患者血清miR-29a表达水平与IFN-γ以及T细胞亚群水平之间的相关性。结果活动组患者血清miR-29a表达水平均显著高于其他肺疾病组以及健康对照组(t=7.005、4.307,P<0.01)。ROC曲线分析表明miR-29a的曲线下面积为0.874,诊断活动性肺结核的敏感度为66.7%,特异度为93.3%。活动组患者血清中IFN-γ的表达水平显著高于其他肺疾病组和健康对照组(t=16.001、14.771,P<0.01)。活动组患者外周血CD_3^+、CD_4^+细胞水平以及CD_4^+/CD_8^+比值显著低于其他肺疾病组和健康对照组(t=7.109、5.601,P<0.01;t=3.133、4.455,P<0.01;t=2.949、2.500,P<0.01),而CD+8细胞水平显著高于其他肺疾病组和健康对照组(t=2.375、2.908,P<0.01)。活动组患者血浆miR-29a水平与IFN-γ水平呈负相关(r=-0.8542,P<0.01)。活动组患者血浆miR-29a水平与外周血CD_3^+、CD_4^+细胞水平以及CD_4^+/CD_8^+比值呈负相关(r=-0.8412、-0.8856、-0.7746,P<0.01),同时与CD_8^+细胞水平呈正相关(r=0.8336,P<0.01)。结论活动期肺结核患者外周血miR-29a表达水平显著升高,影响患者免疫应答功能,可作为诊断活动期肺结核的临床标志物。

Objective To analyze the expression and clinical significance of miR-29a in peripheral blood of patients with active pulmonary tuberculosis（APTB）.Methods Peripheral blood samples were collected from 45 patients with APTB（APTB group）,45 patients with other pulmonary diseases（PD group）and 45 healthy individuals（Control group）respectively.The miR-29a expression was assessed with real-time PCR and ROC curve analysis.The expression level of IFN-γ in serum was detected by using ELISA.The levels of T lymphocyte subsets were measured with flow cytometry.The correlation between serum miRNA-29 and the levels of IFN-γ and T lymphocyte subsets of APTB patients was analyzed.Results The expression levels of miR-29a in APTB group were significantly higher than in the other two groups（t=7.005 and 4.307 respectively,P0.01）.ROC curve showed that the area under the curve of miR-29 was 0.874,with the sensitivity and specificity for diagnosis of APTB being 66.7% and 93.3% respectively.The expression level of IFN-γin APTB group was significantly higher than that in the other two groups（t=16.001 and 14.771 respectively,P0.01）.The levels of CD＋3（t=7.109 and 5.601 respectively,P0.01）,CD_4~＋（t=3.133 and 4.455 respectively,P0.01）and CD_4~＋/CD_8~＋ ratio（t=2.949 and 2.500 respectively,P0.01）in APTB group were significantly lower,while the level of CD_~＋ was significantly higher than in the other two groups（t=2.375 and 2.908 respectively,P0.01）.The serum miR-29a of APTB patients was negatively correlated with IFN-γ（r=-0.8542,P0.001）,CD_3~＋（r=-0.8412,P0.001）,CD_4~＋（r=-0.8856,P0.001）and CD_4~＋/CD_8~＋（r=-0.7746,P0.001）while positively correlated with CD_8~＋（r=0.8336,P0.001）.Conclusion The expression level of miR-29a in peripheral blood of APTB patients is significantly higher,which can be used as a biomarker for the diagnosis of active pulmonary tuberculosis.