Dissecting the interactions between TCR signaling strength and inhibitory pathways

项目摘要/摘要 这个为期5年的K08培训计划旨在促进我(林申博士)在中国的职业发展 作为一名内科科学家，为我的独立研究生涯做准备。我的长期目标是研究 自身免疫性疾病的发病机制和潜在的治疗。这项建议的重点是如何抑制 通路抑制异常的TCR信号强度，以实现外周耐受。中央指导和 培训环境将由我的主要导师Arthur Weiss博士提供，他是TCR信令方面的专家。 进一步的专业知识将由一个强大的专家咨询小组提供，该小组由淋巴细胞信号、免疫 耐受性、自身免疫性和转录图谱。培训计划，包括实验研究、教学和 为了让我朝着我的职业目标前进，已经开发了研讨会。广泛的资源和支持 在加州大学旧金山分校的工作将有助于我独立的道路和我的长期目标。 长期以来，TCR信号的失调被认为在急性髓细胞白血病的发病机制中起着重要作用。 自身免疫性疾病。然而，抑制通路是如何通过增强TCR信号强度来参与 调节外周耐受和预防自身免疫仍然不完全清楚。细胞质 酪氨酸激酶ZAP70在TCR信号转导中起着必要的作用。两个ZAP70多态变异体，强度较大 W131A和较弱的R360P干扰自身抑制，并对TCR信号有不同的影响。作为一名 基础信号增强的结果是，转OTII-TCR基因的W131a T细胞表现出明显的上调 抑制性受体与无能表型的获得。ZAP70 R360P小鼠突变体 源于一种家族性严重自身免疫综合征。R360P小鼠未能显性发育 以C57BL/6为背景的自身免疫性疾病，但表现为调节性和无能T细胞的扩张。 值得注意的是，转OTI-TCR基因的R360P T细胞对弱肽和自体肽的反应增强。 在TCR信号负调控因子Cbl-b中引入缺陷，导致R360P-OTI T细胞增强 W131A-OTII T细胞对弱激动肽的反应和逆转的功能无能。因此，我 假设TCR信号强度增加使T细胞受到更大的抑制控制 但可能使它们对这些抑制通路的破坏更敏感。在这 建议，我将利用R360P和W131A小鼠模型来研究如何增强TCR信号转导 强度和抑制通路耦合在一起，以维持或颠覆外周耐受。在AIM 1，使用一系列的生化技术和转录图谱，我将剖析TCR信号是如何 力量与抑制程序是动态耦合的。在目标2中，我将研究增强的TCR信号 力量提高了对负面调控途径中断的敏感性。这项研究将提供新的 对这些相反的信号通路如何整合以影响T细胞抗原敏感性的机械性见解 并调节外周耐受性和免疫应答质量。

PROJECT SUMMARY/ABSTRACT This 5-year K08 training program is designed to facilitate my (Dr. Lin Shen) career development in preparation of my independent research career as a physician-scientist. My long-term goal is to study the pathogenesis and, potentially, the therapy of autoimmune diseases. This proposal focuses on how inhibitory pathways restrain abnormal TCR signaling strength to achieve peripheral tolerance. Central guidance and the training environment will be provided by my primary mentor, Dr. Arthur Weiss, an expert in TCR signaling. Further expertise will be provided by a strong advisory panel of experts in lymphocyte signaling, immune tolerance, autoimmunity and transcriptomic profiling. A training plan with experimental research, didactics, and seminars has been developed to advance me towards my career goals. The extensive resources and support at the UCSF will facilitate my pathway to independence and my long-term goals. Dysregulation of TCR signaling has long been recognized to play important roles in the pathogenesis of autoimmune diseases. However, how inhibitory pathways are engaged by enhanced TCR signaling strength to regulate peripheral tolerance and prevent autoimmunity remains incompletely understood. The cytoplasmic tyrosine kinase ZAP70 plays a requisite role in TCR signaling. Two ZAP70 hypermorphic mutants, the stronger W131A and the weaker R360P, interfere with autoinhibition and have varying effects on TCR signaling. As a consequence of enhanced basal signaling, OTII-TCR transgenic W131A T cells exhibit marked upregulation of inhibitory receptors and acquisition of an anergic phenotype. The ZAP70 R360P mouse mutant that I generated derives from a familial severe autoimmune syndrome. R360P mice failed to develop overt autoimmune disease on a C57BL/6 background but exhibited expansion of regulatory and anergic T cells. Strikingly, OTI-TCR transgenic R360P T cells showed enhanced responses to weak and self-peptides. Introducing deficiency in Cbl-b, a negative regulator for TCR signaling, resulted in enhanced R360P-OTI T cell responses to a weak agonist peptide and reversed functional anergy in W131A-OTII T cells. Therefore, I hypothesize that increased TCR signaling strength renders T cells subject to greater control by inhibitory pathways but may confer upon them greater sensitivity to disruption of these inhibitory pathways. In this proposal, I will take advantage of the R360P and W131A mouse models to study how enhanced TCR signaling strength and inhibitory pathways are coupled together to either maintain or subvert peripheral tolerance. In Aim 1, using a range of biochemical techniques and transcriptomic profiling, I will dissect how TCR signaling strength is dynamically coupled to inhibitory programs. In Aim 2, I will study whether augmented TCR signaling strength promotes sensitivity to the disruption of negative regulatory pathways. This study will provide new mechanistic insights into how these opposing signaling pathways integrate to impact T cell antigen sensitivity and to regulate peripheral tolerance and the quality of immune responsiveness.