Epigenetic modulation of T cell tolerance in Multiple Sclerosis autoimmunity

项目摘要/摘要 多发性硬化症(MS)是年轻人非创伤性残疾的主要原因，治疗方法有限 这种病很有效，而且无法治愈。在MS及其小鼠实验性自身免疫性脑脊髓炎(EAE)模型中， 炎症T辅助细胞(Th)1和Th17T细胞促进致病性炎症神经环境，而 Th2和调节性T细胞(Treg)是有益的。抑制甲基化反应的策略会抑制 炎症与实验性自身免疫性脑脊髓炎这些影响被归因于 抑制蛋白质精氨酸甲基转移酶(PRMT)，一种调节基因表达的酶家族 并通过催化组蛋白和其他蛋白质上的精氨酸甲基化来发挥活性。然而，由于缺乏了解， PRMT对T细胞效应器功能和选择性精氨酸缺乏的调节作用 到目前为止，甲基转移酶抑制剂阻止了该领域的进一步发展，以及 这些发现的临床应用。我们已经开发出一流的PRMT5特异性抑制剂。这些 抑制剂抑制EAE和促炎性Th1/Th17细胞反应，同时维持/增加 Treg/Th2应答。我们假设PRMT5介导的对称二甲基化反应 通过促进和维持炎性T细胞反应促进自身免疫。拿走 在T细胞表型和EAE的分子机制方面的独特专业知识组合的优势 自身免疫(Guerau)、PRMT5特异性抑制药/信号通路(Baiocchi)和新的CRISPRI 技术(HAN)，我们建议通过解剖确定甲基化促进自身免疫的机制 PRMT5在驱动T细胞炎症反应的特定途径中的作用。同时使用体外和 临床前的髓鞘特异性T细胞驱动的多发性硬化疾病的体内模型，我们建议：1)定义信号和 CD4T细胞活化/分化过程中PRMT5表达的调控机制 炎症表型与调节表型，2)决定PRMT5活性在 炎性T细胞反应和3)确定T细胞特异性PRMT5调节对临床的影响 这些实验将确定疾病活动性在过继转移EAE小鼠模型中的作用。 PRMT5在导致中枢神经系统髓鞘特异性T细胞反应的发生和致病潜能中的作用 自身免疫力。在完成这些目标后，我们将了解PRMT5催化的精氨酸是如何 甲基化塑造T细胞的表型和扩增，以及这些效应如何塑造获得性免疫 对髓鞘抗原的反应。这些实验将首次解决PRMT5在炎症中的作用 用新的特定药物研究自身免疫T细胞反应和疾病。由于小鼠和人类PRMT5都是 这些药物高度保守和有针对性，这些研究可能转化为新的治疗策略 治疗多发性硬化和其他自身免疫性疾病。

PROJECT SUMMARY/ABSTRACT Multiple Sclerosis (MS) is the leading cause of non-traumatic disability in young adults, therapies have limited efficacy and there is no cure. In MS and its mouse model Experimental Autoimmune Encephalomyelitis (EAE), inflammatory T helper (Th)1 and Th17 T cells promote a pathogenic inflammatory neural environment while Th2 and regulatory T cells (Treg) are beneficial. Strategies that inhibit methylation reactions suppress inflammation and Experimental Autoimmune Encephalomyelitis (EAE). These effects have been attributed to inhibition of Protein Arginine Methyl Transferases (PRMT), a family of enzymes that regulate gene expression and activity by catalyzing arginine methylation on histones and other proteins. However, lack of understanding of which and how PRMTs modulate T cell effector function and lack of selective arginine methyltransferase inhibitors has so far prevented further advancement in the field, as well as the clinical application of these findings. We have developed first-in-class PRMT5-specific inhibitors. These inhibitors suppressed EAE and pro-inflammatory Th1/Th17 cell responses while maintaining/increasing Treg/Th2 responses. We hypothesize that PRMT5-mediated symmetric dimethylation reactions contribute to autoimmunity by promoting and sustaining inflammatory T cell responses. Taking advantage of the unique combination of expertise in molecular mechanisms of T cell phenotype and EAE autoimmunity (Guerau), PRMT5-specific inhibitor drugs/signaling pathways (Baiocchi) and novel CRISPRi technology (Han), we propose to identify a mechanism for methylation-promoted autoimmunity by dissecting the role of PRMT5 on specific pathways that drive T cell inflammatory responses. Using both in vitro and preclinical in vivo models of myelin-specific T cell driven MS disease, we propose to: 1) define the signals and regulatory mechanisms governing PRMT5 expression during CD4 T cell activation/differentiation into inflammatory vs. regulatory phenotypes, 2) determine the mechanistic consequences of PRMT5 activity on inflammatory T cell responses and 3) determine the impact of T cell-specific PRMT5 modulation on clinical disease activity in the adoptive transfer EAE mouse model of MS. These experiments will determine the role of PRMT5 in the development and pathogenic potential of myelin-specific T cell responses that lead to CNS autoimmunity. At the completion of these aims, we will have learned how PRMT5-catalyzed arginine methylation shapes the phenotype and expansion of T cells and how these effects shape the adaptive immune response to myelin antigens. These experiments will be the first to address the role of PRMT5 in inflammatory autoimmune T cell responses and disease with novel specific drugs. Since both mouse and human PRMT5 are highly conserved and targeted by these drugs, these studies could translate to novel therapeutic strategies to treat MS and other autoimmune diseases.