An integrative structural biology approach to the study of T cell signaling

研究 T 细胞信号传导的综合结构生物学方法

• 批准号: 10191789
• 负责人: Nikolaos Sgourakis
• 金额: $ 11.77万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10191789
• 关键词: integrative; structural; biology; approach; study

Summary I propose to develop and apply innovative hybrid structural biology tools to investigate the molecular mechanism of signaling through the T cell receptor (TCR) complex. This is a fundamental adaptive immunity pathway through which cytotoxic CD8+ T cells can detect the presence of viruses and developing tumors in the body. Immune function is achieved through the continuous surveillance of antigen-presenting cells for short peptides displayed within the molecules of the Major Histocompatibility Complex (MHC) on the cell surface. Key to the initiation of signaling, is a multi-subunit membrane protein assembly consisting of a clonotypic TCR heterodimer that recognizes the peptide-MHC, together with the invariant CD3 co-receptor hexamer that relays an activation signal from the cell surface intracellularly, through the plasma membrane. Besides the fundamental basic science merit, characterizing this process at atomic detail has important clinical implications, as is suggested by the large number of immunodeficiencies resulting from dysregulation of the signaling components and their interactions. Despite a large number of functional and structural studies, elucidating the 3D structure of the signaling complex as a whole remains extremely challenging by conventional methods, due to its size and dynamic complexity. As a result, the interactions between the TCR and CD3 subunits and the crucial conformational changes needed for signaling remain incompletely characterized. With these bottlenecks in mind, I have developed a new methodology combining datasets from complementary approaches, such as NMR, SANS and cryoEM, together with computational modeling using the program Rosetta to solve the structures of such challenging complexes. Here, I propose to apply this powerful integrative approach to elucidate the T cell receptor complex structure, and to study its dynamic transitions between inactive and active conformations. My immediate goal is to determine the molecular basis of TCR/CD3 interactions and to characterize the crucial structural changes in receptor complex arrangement upon antigen recognition. As a long-term goal, I plan to use a structure-guided approach to engineer novel T cell receptors with custom specificities and signaling properties, to be used in emerging immunotherapy applications.

概括 我建议开发和应用创新的混合结构生物学工具来研究 通过 T 细胞受体 (TCR) 复合物进行信号传导的分子机制。这是一个 基本的适应性免疫途径，细胞毒性 CD8+ T 细胞可以通过该途径检测 体内存在病毒和正在形成肿瘤。免疫功能是通过以下方式实现的 连续监视抗原呈递细胞中显示的短肽 细胞表面主要组织相容性复合物 (MHC) 分子。启动的关键 信号传导，是由克隆型 TCR 组成的多亚基膜蛋白组装体 识别肽-MHC 的异二聚体以及不变的 CD3 共受体 六聚体，通过血浆在细胞内传递来自细胞表面的激活信号 膜。除了基本的基础科学价值外，在原子层面表征这个过程 正如大量研究表明的那样，细节具有重要的临床意义 由于信号成分及其调节失调而导致的免疫缺陷 互动。 尽管进行了大量的功能和结构研究，但仍无法阐明其 3D 结构 信号复合体作为一个整体对于传统方法来说仍然极具挑战性，因为 它的大小和动态复杂性。因此，TCR 和 CD3 亚基之间的相互作用 信号传导所需的关键构象变化仍未完全表征。 考虑到这些瓶颈，我开发了一种新的方法，结合了来自 互补方法，例如 NMR、SANS 和 CryoEM，以及计算方法 使用 Rosetta 程序进行建模来解决此类具有挑战性的复合物的结构。 在这里，我建议应用这种强大的综合方法来阐明 T 细胞受体 复杂的结构，并研究其非活性和活性之间的动态转变 构象。我的近期目标是确定 TCR/CD3 相互作用的分子基础 并表征抗原上受体复合物排列的关键结构变化 认出。作为一个长期目标，我计划使用结构引导的方法来设计新颖的 T 具有定制特异性和信号传导特性的细胞受体，用于新兴的 免疫治疗应用。