Decoding synovial CD4+ T cell antigen specificities in Rheumatoid Arthritis

项目摘要/摘要 类风湿关节炎(RA)是一种以慢性炎症性疾病为特征的流行的自身免疫性疾病 导致联合销毁的进程。在免疫学上，自身反应性的CD4+T细胞在 疾病病理和激活B细胞，导致滑膜和滑膜内的病理性淋巴聚集 自身抗体的产生。尽管识别致病的CD4+T细胞识别的分子靶点是一种 了解RA分子基础的关键第一步，我们仍然不知道RA的抗原靶点 绝大多数滑膜中的CD4+T细胞以及这些反应与自身抗体反应的关系。我们有 开发了一条在RA中发现CD4+T细胞抗原的管道，该管道依赖于一种新的基于细胞的基因筛查 能够在基因组范围内绘制TCR特异性图谱的技术。基于我们初步的单细胞 转录数据，我们已经在滑液中发现了几个有趣的CD4+T细胞群，它们是 克隆性扩张，并开始发现他们的TCR目标。 这项提议是一项为期五年的研究和培训计划，科学上的重点是确定抗原靶标。 从RA滑膜克隆扩增的CD4+T细胞，并了解这些抗原如何与 自身抗体反应。我们在目标1中建议绘制抗原表位图并评估相应的 节段性抗原发现对克隆性扩增的滑膜CD4+TCRs的限制 屏幕。目的2通过询问抗体库来解剖关节炎关节中T细胞-B细胞的协同作用 结合特异性和进行CD4+T细胞-B细胞共培养试验。最后，在目标3中，我们将设计一个 抗原发现平台，使我们能够发现滑膜TCR反应性 瓜氨酸肽抗原，在类风湿关节炎中观察到的一种显著的翻译后修饰。 这项研究将尖端的遗传和转录技术与机械工作结合在一起，关键是 评估类风湿性关节炎的抗原特异性景观。它将为应聘者提供几个科学方面的新培训 从事转译免疫学研究的领域。应聘者近期的职业发展目标是 获得生物信息学分析、抗体图谱技术和人类免疫学分析的经验。 候选人和导师史蒂芬·埃利奇博士都描述了具体的职业发展计划， 功能基因组学和技术开发方面的专家，以及迈克尔·布伦纳博士， 淋巴细胞生物学和类风湿性关节炎，利用布里格姆和妇女医院提供的强大资源 医院和哈佛医学院。候选人的长期职业目标是获得终身教职 领导致力于研究抗原特异性免疫的不同合作科学家小组的职位 风湿性和自身免疫性疾病的反应及其在治疗中的潜在应用。

Project Summary/Abstract Rheumatoid arthritis (RA) is a prevalent autoimmune disorder characterized by chronic inflammatory processes that lead to joint destruction. Immunologically, autoreactive CD4+ T cells play a central role in disease pathology and activate B cells leading to pathologic lymphoid aggregates within the synovium and autoantibody production. Although identifying the molecular targets recognized by pathogenic CD4+ T cells is a critical first step in understanding the molecular basis of RA, we still do not know the antigenic targets for the vast majority of synovial CD4+ T cells and how such reactivities relate to autoantibody responses. We have developed a pipeline for CD4+ T cell antigen discovery in RA that relies on a new, cell-based genetic-screening technology that enables mapping of TCR specificities at genome scale. Based on our preliminary single-cell transcriptomic data, we have identified several interesting CD4+ T cell populations in synovial fluid that are clonally expanded and have begun to discover their TCR targets. This proposal is a five-year research and training plan with a scientific focus on identifying the antigenic targets of clonally expanded CD4+ T cells from RA synovium and understanding how such antigens relate to autoantibody responses. We propose in Aim 1 to map the antigenic epitopes and assess the corresponding HLA-restriction of clonally expanded synovial CD4+ TCRs by performing peptidome-wide antigen discovery screens. Aim 2 dissects T cell-B cell collaboration in the arthritic joint by interrogating antibody repertoire binding specificities and performing CD4+ T cell-B cell co-culture assays. Finally in Aim 3, we will engineer an antigen discovery platform to enable our ability to uncover synovial TCR reactivities against citrullinated-peptide antigens, a prominent post-translational modification observed in RA. This study combines cutting-edge genetic and transcriptomic technologies with mechanistic work to critically evaluate the antigen-specific landscape of RA. It will provide the candidate new training in several scientific areas to pursue translational immunology research. The candidate’s immediate career development goals are to gain experience with bioinformatic analysis, antibody profiling technologies, and human immunology assays. A specific career development plan is described by both the candidate and the mentors, Dr. Stephen Elledge, an expert in functional genomics and technology development, and Dr. Michael Brenner MD, an expert in lymphocyte biology and RA, taking advantage of the powerful resources available at Brigham and Women’s Hospital and Harvard Medical School. The candidate’s long-term career goal is to attain a tenure-track faculty position leading a diverse group of collaborative scientists dedicated to studying antigen specific immune responses in rheumatic and autoimmune diseases and their potential applications for therapy.