DNA甲基化-miRNA表观遗传修饰参与了多种自身免疫性疾病的调控，但其在重症肌无力（MG）中的作用并不明确，我们的前期研究发现，miR-155和miR-146a在MG的异常免疫应答中发挥重要作用，MG患者CD4+T细胞中多个自身免疫相关基因出现甲基化异常。本项目拟进一步联合使用Illumina全基因组甲基化芯片和miRNA芯片探讨DNA甲基化-miRNA调节网络对MG患者CD4+T细胞免疫失衡的影响；利用单链抗体scFvCD4-9R负载siRNA靶向诱导CD4+T细胞差异基因甲基化，从细胞和整体水平探索DNA甲基化的精细调控在CD4+T细胞免疫应答中的作用；利用双荧光素酶报告基因、miRNA过表达和抑制试验对筛选出的miRNA-DNMT通路进行验证并探讨miRNA对DNA甲基化的的影响，从而阐明DNA甲基化-miRNA调控网络在MG发病中的作用及机制，为开发新的表观治疗方略提供理论依据。

The modification of DNA methylation-miRNA epigenetic network is involved in immune disorders of a variety of autoimmune diseases, less is known about its role in the pathogenesis of MG. Our preliminary study had found that miR-155 and miR-146a play an important role in the abnormal immune response in MG patients, in addition, multiple autoimmune-related genes in CD4+T cells from MG patients were found to be aberrantly methylated . On this project, we will further explore the potential influence of DNA methylation-miRNA regulatory network on gene dysregulation of CD4+T cells and immune disorders in MG patients through integrated analysis of DNA methylation and miRNA expression; then to evaluate the fine regulation of DNA methylation on CD4+T cells both at cellular and whole animal levels, using scFvFoxp3-9R fusing with siRNA to induce the promoter of key gene methylation; to validate the screened miRNA-DNMT pathway through the dual luciferase reporter gene assay, miRNA over-expression and inhibition techniques，with a purpose to evaluate the potential impact of miRNA on DNA methylaion. We attempt to explore the DNA methylation-miRNA modificaion network in the pathogenesis of MG and provide a theoretical basis for new epigenetic therapy through this research.