Th17细胞与重症肌无力发病及临床严重度相关性研究

Pathogenetic role of T helper type 17 cells and related cytokines in myasthenia gravis

目的研究伴胸腺瘤重症肌无力(myasthenia gravis,MG)患者外周血中Th17细胞及其相关细胞因子变化,探讨Th17细胞与MG疾病临床严重度及血清乙酰胆碱受体抗体(anti-acetylcholine receptor autoanti-bodies,AChR-Ab)水平的关系。方法采用流式细胞术检测MG患者及健康对照(对照组)外周血单个淋巴细胞悬液(PBMCs)Th17细胞比例,采用实时定量PCR方法检测PBMCs中Th17细胞相关细胞因子mRNA转录水平;采用ELISA法检测血清中Th17细胞相关细胞因子表达及AChR-Ab水平;使用美国重症肌无力协会QMG评分评价MG临床严重程度。结果 MG伴胸腺瘤组外周血Th17细胞比例〔(1.57±0.56)%〕显著高于对照组〔(0.94±0.32)%,P=0.031〕;MG伴胸腺瘤组IL-17mRNA转录相对水平(23.16±4.72)高于对照组(14.82±3.03,P=0.0083),IL-1βmRNA、IL-6mRNA、ROR-γmRNA、IL-23mRNA相对转录水平分别为7.36±2.14、8.96±1.93、18.46±2.11、1.32±0.25,均高于对照组(分别为4.61±1.68,P=0.039;4.61±1.68,P=0.037;0.78±0.25,P=0.028;12.84±2.97,P=0.041);MG伴胸腺瘤组血清IL-17表达量〔(30.0±7.2)pg/mL〕高于对照组〔(20.0±4.9)pg/mL,P=0.029〕,IL-1β、IL-23表达量分别为(72.0±11.5)、(208±85.6)pg/mL,均高于对照组〔分别(45.0±9.3)pg/mL,P=0.034;(93.0±48.3)pg/mL,P=0.004〕。伴胸腺瘤MG患者QMG评分与Th17细胞比例呈正相关(r=0.74,P=0.034)。MG患者外周血Th17细胞比例与血清AChR-Ab水平呈正相关(r=0.81,P=0.026)。结论 MG胸腺瘤中Th17细胞增多,可能导致免疫调节功能紊乱,从而引起MG发病。

Objective To investigate the immunoregulatory roles of Th17 cells and their related cytokines in myasthenia gravis （MG）.Methods 102 MG patients were divided into three groups：MG with thymoma （TM）,MG with thymic hyperplasia （TH） and MG with normal thymus （NT）.Th17 cells from peripheral blood mononuclear cells （PBMCs） were measured with flow cytometry.Th17 related cytokines were detected with enzyme-linked immunosorbent assay （ELISA） and their mRNAs were detected by realtime reverse trancription polymerase chain reaction （Realtime RT-PCR）.The concentration of anti-AChR antibodies were detected by ELISA.Results The quantity of Th17 cells in MG patients with thymoma （1.57 ％ ± 0.56 ％） were significantly increased compared with that of healthy control （0.94 ％ ±0.32 ％,P=0.031）.The levels of IL-17 mRNA （23.16±4.72） were up-regulated significantly versus those in HC group （14.82±3.03,P=0.0083）.The expression levels of IL-1β mRNA （7.36零2.14） were up-regulated significantly versus those in the HC group （4.61±1.68,P=0.039）.The expression levels of IL-6 mRNA （8.96± 1.93） were up-regulated significantly versus those in the HC group （4.61±1.68,P=0.037）.The expression levels of ROR-γ mRNA （1.32±0.25） were up-regulated significantly versus those in the HC group （0.78±0.25,P=0.028）.The expression levels of IL-23 mRNA （18.46±2.11） were up-regulated significantly versus those in the HC group （12.84±2.97,P=0.041）.The mean concentration of IL-17A was up-regulated significantly in the TM group [（30.0±7.2） pg/mL] versus the HC group [（20.0± 4.9） pg/mL,P=0.029].Serum level of IL-23 was up-regulated significantly in TM group [（208±85.6） pg/mL] versus the HC group [（93.0±48.3） pg/mL,P=0.004] and the level of IL-1β was up-regulated significantly in the TM group [（72.0±11.5） pg/mL] versus the HC group [（45.0±9.3） pg/mL,P=0.034].The quantity of Th17 cells correlates with the quantitative myasthenia gravis （QMG） score in patients with TM.Furthermore,we also found a significant positive correlation between the percentage of Th17 cells （％） and the concentration of AChR antibodies in MG patients.Conclusions The elevated serum levels of IL-17 and other Th17 related cytokines in MG patients with thymoma may reveal the severity of the disease,which is valuable in the diagnosis and choice of therapeutic strategy for MG patients.