结核性脑膜炎患者脑脊液外泌体中Let-7b的表达水平及临床意义

Expression of Let-7b in cerebrospinal fluid exosomes of tuberculous meningitis and clinical significance

目的研究结核性脑膜炎患者脑脊液外泌体中Let-7b的表达水平及临床意义。方法采用病例对照研究,收集结核性脑膜炎患者、病毒性脑膜炎患者及健康对照者脑脊液各15例,使用试剂盒法分离提纯脑脊液外泌体,应用荧光实时定量聚合酶链反应法检测各组脑脊液外泌体中let-7b相对表达水平。结果 (1)结核性脑膜炎和病毒性脑膜炎及对照组脑脊液中均可以检测到外泌体,透射电镜下呈圆形或椭圆形,直径约30～100 nm。荧光定量PCR检测发现3组脑脊液外泌体中均可检测到let-7b;(2)结脑组脑脊液外泌体中let-7b的表达显著低于对照组,差异具有明显统计学意义(P <0. 05);(3)病脑组与对照组相比,病脑组let-7b表达下调,差异具有统计学意义(P <0. 05);(4)结脑组与病脑组相比,结脑组let-7b表达下调,但该差异无统计学意义(P> 0. 05)。结论 let-7b在结核性脑膜炎患者脑脊液外泌体中表达下调,可作为该疾病的诊断及相关脑炎的鉴别诊断的潜在生物学标志物。

Objective Intrigate expression of Let-7b in cerebrospinal fluid exosomes of tuberculous meningitis.Methods The cerebrospinal fluid of 15 cases of tuberculous meningitis(TBM group),15 cases of viral meningitis(VM group),and 15 cases of normal cerebrospinal fluid(control group)were diagnosed and treated by our Department of Neurology in 2017-2018.ExoQuick precipitation extraction was used to separate and purify exosomes.Transmission electron microscopy was used to observe the morphology of different groups of exosomes and Western blotting to detect exosome markers.qRT-PCR was used to detect the expression of let-7b in cerebrospinal fluid exosomes.Results(1)The exosomes could be detected in cerebrospinal fluid of tuberculous meningitis and viral meningitis and the control group,they were round or oval under transmission electron microscope and had a diameter of about 30 to 100 nm.Fluorescent quantitative PCR assays detected let-7b in 3 groups of cerebrospinal fluid exosomes.(2)The expression level of let-7b in cerebrospinal fluid exosomes was significantly lower in patients with tuberculous meningitis than in the control group(P<0.05).(3)The expression of let-7b was down-regulated in viral meningitis compared with the control group,There was statistical significance between them(P<0.05).(4)The expression level of let-7b in tuberculous meningitis was lower than that in viral meningitis,but there was no statistical significance of them(P>0.05).Conclusion We extracted let-7b in cerebrospinal fluid exosomes from TBM,viral meningitis and normal controls to observe the expression level of let-7b and explore new biomarkers for meningitis.