Somatic Mutation in the Etiology of Multiple Sclerosis

项目摘要 自身免疫性疾病是一个由80多种慢性、致残性疾病组成的家族，其中免疫缺陷是一种免疫缺陷。 系统引导身体攻击自身组织的正常成分（自身抗原）。自身免疫性疾病 仅在美国就影响了1470万至2350万人（5 - 8%），使其成为最常见的疾病之一。 人类疾病。然而，尽管大量的研究致力于了解自身免疫， 对引发自身免疫反应的关键病因事件的连贯解释仍然缺乏。 自身免疫性疾病的家族聚集性表明，疾病风险的增加，遗传易感性， 是可以遗传的。但即使在风险是遗传的环境中，疾病的发作也会发生在一个变量之后， 延迟，这表明额外的随机过程是必要的，以触发疾病的发作。这 这一现象让人想起在癌症中观察到的情况，在癌症中，遗传易感性可以是 然而，癌症只有在额外靶基因的体细胞突变发生后才会发展。因此 本提案中描述的项目的目标是检验基因中的体细胞突变的假设， 调节免疫耐受是启动自身免疫所必需的，通过进行基于单细胞RNA-seq的 来自多发性硬化（MS）患者的致病性淋巴细胞的表达谱和序列分析。 虽然MS患者的中枢神经系统（CNS）中发现的炎性病变包括复杂的神经系统炎性病变，但MS患者的中枢神经系统炎性病变包括复杂的神经系统炎性病变。 T细胞、B细胞和巨噬细胞的混合物，克隆扩增的、受体编辑的和 体细胞突变的记忆B细胞在脑脊液（CSF）中表达脑反应性抗体， 以及对B细胞去除疗法的显著临床反应，表明自身反应性B细胞在肿瘤的治疗中起关键作用。 在MS病理学中的作用，因此是拟议研究的重点。 提出了三个具体目标：1。确定MS患者CSF中的致病性B细胞是否携带体细胞 参与调节B细胞耐受性的基因突变，2.确定MS CSF中是否存在致病性B细胞 患者表现出组成型或响应于激活信号的改变的转录谱，以及3. 研究在耐受性相关信号通路上检测到的体细胞突变的功能相关性。 通过单个CSF B细胞mRNA序列和表达数据的全基因组比较分析 从MS患者中，我们希望确定是否可以在致病性MS中鉴定体细胞突变及其影响。 细胞我们还将开发出一种经过验证的单细胞RNA-seq方法，用于进行类似的研究。 在其他自身免疫性疾病和免疫反应环境中的研究。先进的单机开发 细胞基因组学方法，这将使我们能够探索体细胞突变和差异表达的潜在作用。 基因表达在多发性硬化症病因中的作用将是一个真实的游戏规则改变者。体细胞突变作用的证据 在MS病因学和/或病理学中的应用将完全改变我们对自身免疫性疾病发展的看法 并且将对替代的个性化治疗方法的发展具有广泛的影响。 OMB编号0925-0001/0002（2012年8月批准至2015年8月31日修订版）页码续页格式页码

Project Summary Autoimmune diseases are a family of over 80 chronic, disabling illnesses in which defects in the immune system leads the body to attack normal components (self antigens) of its own tissues. Autoimmune disease affects 14.7 – 23.5 million people in the U.S. alone (5 – 8%), making it one of the most common classes of human diseases. However, despite considerable research being devoted to understanding autoimmunity, a coherent explanation of the critical causative events that initiate the autoimmune response is still lacking. Familial clustering of autoimmune disease indicates that an increased risk of disease, a genetic predisposition, can be inherited. But even in settings in which risk is inherited, disease onset is found to occur after a variable delay, suggesting that additional stochastic processes are necessary to trigger disease onset. This phenomenon is reminiscent of what has been observed in cancer where a genetic predisposition can be inherited, and yet cancer develops only after somatic mutations in additional target genes occur. Thus, the goal of the project described in this proposal is to test the hypothesis that somatic mutations in genes that regulate immune tolerance are required to initiate autoimmunity, by performing single cell RNA-seq-based expression profiling and sequence analysis of pathogenic lymphocytes from multiple sclerosis (MS) patients. Although the inflammatory lesions found in the central nervous system (CNS) of MS patients include a complex mixture of T cells, B cells and macrophages, the presence of clonally-expanded, receptor-edited and somatically-mutated memory B cells that express brain-reactive antibodies in the cerebrospinal fluid (CSF), and the dramatic clinical response to B cell depletion therapy, suggest that autoreactive B cells play a critical role in MS pathology, and are therefore the focus of the proposed studies. Three specific aims are proposed: 1. Determine if pathogenic B cells in the CSF of MS patients carry somatic mutations in genes involved in regulating B cell tolerance, 2. Determine if pathogenic B cells in the CSF of MS patients exhibit altered transcriptional profiles either constitutively or in response to activating signals, and 3. Investigate the functional relevance of somatic mutations detected on tolerance-related signaling pathways. Through the genome-wide comparative analysis of mRNA sequence and expression data of single CSF B cells from MS patients we expect to determine if somatic mutations and their effects can be identified in pathogenic cells. We will also have developed a validated single cell RNA-seq methodology for the conduct of similar studies in other autoimmune disease and immune response settings. The development of advanced single cell genomic methodologies that will allow us to explore the potential role of somatic mutations and differential gene expression in the etiology of MS will be a real game changer. Evidence for a role for somatic mutations in MS etiology and/or pathology would completely change the way we view autoimmune disease development and would have broad implications for the development of alternative personalized treatment approaches. OMB No. 0925-0001/0002 (Rev. 08/12 Approved Through 8/31/2015) Page Continuation Format Page