Mechanical basis of T cell receptor triggering

T细胞受体触发的机械基础

• 批准号: 8699495
• 负责人: MATTHEW J LANG
• 金额: $ 40.68万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-23 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8699495
• 关键词: Address; Affinity; Anisotropy; Antigen-Presenting Cells; Area; Behavior; Binding; Biological; Biological Assay; CD3 Antigens; Cell model; Cell surface; Cells; Chemicals; Complex; Crowding; Discipline; Discrimination; Environment; Event; Exhibits; Faculty; Fluorescence; Fluorescence Anisotropy; Foundations; Future; Human Resources; Immune; Immune response; Immunologic Surveillance; Immunology; In Vitro; Kinetics; Lead; Life; Ligands; Ligation; Location; Major Histocompatibility Complex; Measurement; Measures; Mechanics; Methods; Monitor; Mutation; Nature; Organism; Outcome; Peptide/MHC Complex; Peptides; Play; Population; Process; Production; Receptor Activation; Receptor Signaling; Recombinant Proteins; Rheology; Role; Running; Rupture; Sea; Signal Transduction; Solutions; Specificity; Spectrum Analysis; Structure; Surface; System; T-Cell Receptor; T-Lymphocyte; TCR Activation; Testing; Training; Transducers; Transmembrane Domain; Work; base; density; design; flexibility; immune activation; lymph nodes; mutant; pathogen; preference; protein expression; receptor; receptor function; single molecule; thymocyte; transmission process; tumor

DESCRIPTION (provided by applicant): The mammalian organism contains millions of distinct T cells, each with their own unique specificity. T cells are essential components of the adaptive immune response, being critical to the defense of our bodies against foreign pathogens and tumors that create cellular alterations. The T cell receptor (TCR), a multimeric transmembrane complex, is highly adaptive, capable of distinguishing foreign peptides bound to self- major histocompatibility complex molecules (pMHC) displayed on the surface of altered cells. External flags in the form of these presented peptides displayed on antigen presenting cells are sensed and transmitted into the T cell during its process of immune surveillance. Once recognized by the T cell, immune activation is initiated to destroy the non-self "invader". How recognition of ths peptide by a weakly interacting specific receptor on the T cell surface evokes signaling remains an undefined, longstanding, biological question. Our preliminary studies identified via focused experimentation the importance of physical forces in activating T cells, providing a mechanical mechanism to answer the long standing biological question of how minute differences at the TCR pMHC interface lead to triggering. Our objective is to test the hypothesis that the TCR acts as an anisotropic mechanosensor. The concept that mechanical force plays a role in TCR activation will be explored across physiologically relevant model cell-based systems as well as be adapted to classical single molecule assay design. We combine single molecule methods, structure function mutational analysis, and recombinant protein expression specifically targeted to the T cell triggering event. First, we determine the physical and chemical requirements for TCR triggering on cells. Second, we develop a single molecule assay for probing the strength of the TCR-pMHC bond across a range of loads with peptides exhibiting varying potencies. Third, we determine the role of the stalk domain as a force transducer for T cell triggering in live T cells. Outcome of this work will provide a clearer understanding for the temporal, chemical, spatial and physical inputs to TCR mechanosensing. Our project includes training of personnel at levels ranging from undergraduates to faculty with crucial interdisciplinary overlap between labs founded in single molecule measurement and immunology disciplines.

描述（由申请人提供）：哺乳动物生物体含有数百万个不同的T细胞，每个T细胞都具有自己独特的特异性。T细胞是适应性免疫反应的重要组成部分，对于我们的身体防御外来病原体和肿瘤造成细胞改变至关重要。T细胞受体（TCR）是一种多聚体跨膜复合物，具有高度适应性，能够区分与改变细胞表面上展示的自身主要组织相容性复合物分子（pMHC）结合的外源肽。在抗原呈递细胞上展示的这些呈递肽形式的外部标志在其免疫监视过程中被感知并传递到T细胞中。一旦被T细胞识别，免疫激活被启动以摧毁非自我“入侵者”。T细胞表面上弱相互作用的特异性受体如何识别ths肽引起信号传导仍然是一个未定义的，长期存在的生物学问题。我们的初步研究通过集中实验确定了物理力在激活T细胞中的重要性，提供了一种机械机制来回答长期存在的生物学问题，即TCR pMHC界面的微小差异如何导致触发。我们的目标是测试的假设，TCR作为一个各向异性的机械传感器。机械力在TCR活化中起作用的概念将在基于生理学相关模型细胞的系统中进行探索，并适用于经典的单分子测定设计。我们结合了联合收割机单分子方法、结构功能突变分析和特异性靶向T细胞触发事件的重组蛋白表达。首先，我们确定TCR触发细胞的物理和化学要求。第二，我们开发了一种单分子测定法，用于探测TCR-pMHC结合的强度，该结合跨越一系列负载，具有表现出不同效力的肽。第三，我们确定的茎域的作用，作为一个力传感器的T细胞触发活T细胞。这项工作的结果将提供一个更清晰的理解的时间，化学，空间和物理输入TCR机械传感。我们的项目包括从本科生到教师的人员培训，在单分子测量和免疫学学科建立的实验室之间具有重要的跨学科重叠。