【摘要】 目的:探讨肿瘤坏死因子受体相关因子-6(TRAF-6)是否在Graves病(GD)的发生过程中发挥免疫耐受作用及其可能的机制。方法:纳入Graves病初诊患者(GD) 30例,GD缓解期患者(e GD) 30例及健康人群(NC) 28例。提取外周血单个核细胞(PBMCs),分别采用实时定量PCR检测维甲酸相关孤儿受体(RORγt)、叉头蛋白P3(Foxp3)、白介素-2(IL-2)、TRAF-6 mRNA的表达,Western blot检测p-Smad2/Smad3、总Smad2/Smad3、TRAF-6蛋白的表达,ELISA检测血浆中转化生长因子-β1(TGF-β1)、IL-2、IL-17A、IL-10蛋白的表达。结果:①与NC组相比,GD组中IL-2的mRNA和蛋白、Foxp3 mRNA和IL-10蛋白的表达水平均减少,而RORγt mRNA和IL-17A蛋白的表达水平均增加,以上结果差异均有统计学意义(P<0. 05)。②与NC组相比,GD组中TGF-β1蛋白的表达水平降低,差异有统计学意义(P<0. 05); GD组中p-Smad2/Smad3的蛋白表达较NC组有上升趋势(P>0. 05)。③GD组中的TRAF-6 mRNA与NC组比较表达降低,差异有统计学意义(P<0. 05); TRAF-6蛋白表达较NC组有下降趋势(P>0. 05)。④e GD组中TRAF-6 mRNA的表达水平较GD组增加,差异有统计学意义(P<0. 05),较NC组差异无统计学意义(P>0. 05);其余指标在e GD组与GD组、e GD组和NC组之间的差异均没有统计学意义(P>0. 05)。结论:GD患者中TRAF-6低表达不足以抑制TGF-β1介导的Smad2/Smad3磷酸化,导致增多的Smad2/Smad3磷酸化蛋白下调IL-2表达,进而诱导Th17细胞的分化,同时抑制Treg细胞的分化,使机体不能维持免疫耐受,促进GD的发生。更多还原

【Abstract】 Objective: To investigate whether tumor necrosis factor receptor-associated factor-6( TRAF-6) exerts immune tolerance during the development of Graves’ disease( GD) and its possible mechanism. Methods: 30 GD newly diagnosed patients( GD group),30 GD remission patients( e GD group) and 28 healthy subjects( NC group) were recruited in this study. Peripheral blood mononuclear cells( PBMCs) were extracted and the mRNA expression of retinoid-related orphan receptor gamma t( RORγt),forkhead box protein p3( Foxp3),interleukine-2( IL-2) and TRAF-6 were detected by real-time quantitative PCR( RT-PCR). TRAF-6,pSmad2,p-Smad3,and total Smad2/3 protein expression were determined by Western blot. ELISA was used to detect the expression of transforming growth factor-β1( TGF-β1),IL-2,IL-17 A and IL-10 in plasma. Results: ①The mRNA and protein expression of IL-2,Foxp3 mRNA and IL-10 protein expression in the GD group were significantly lower than those in the NC group,while RORγt mRNA and IL-17 protein expression were significantly higher than those in the NC group( P<0. 05). ②The TGF-β1 protein level in the GD group was significantly lower than that in the NC group( P <0. 05). The protein expression of p-Smad/Smad3 was higher in the GD group than those in the NC group( P>0. 05). ③The expression of TRAF-6 mRNA in GD group was significantly lower than that in NC group( P<0. 05). The expression of TRAF-6 protein was lower than NC group( P>0. 05). ④The expression level of TRAF-6 mRNA in the e GD group was significantly higher than that in the GD group( P<0. 05),but no significant difference was found between the e GD group and the NC group( P > 0. 05). There was no significant difference in other indexes between e GD group and GD group,and between e GD group and NC group( P>0. 05). Conclusion: TRAF-6 may play an immunotolerant role in the development of GD. Low expression of TRAF-6 may be not sufficient to inhibit the phosphorylation of Smad2/3 by TGF-β1,while increased phosphorylation of Smad2/3 down-regulate the expression of IL-2,inducing the differentiation of Th17 cells and inhibiting the differentiation of Treg cells,which makes it impossible for the host to maintain immune tolerance and promote the development of GD.更多还原