Probing the mechanistic basis for T cell fate decisions (R01)

探讨T细胞命运决定的机制基础（R01）

• 批准号: 8702920
• 负责人: Michael S Kuhns
• 金额: $ 37.88万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-10 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8702920
• 关键词: Address; Antigen-Presenting Cells; Antigens; Architecture; Attenuated; Autoantigens; Biochemical; Biological Assay; Biological Models; CD28 gene; CD3 Antigens; CD4 Positive T Lymphocytes; CD80 gene; Cancer Vaccines; Cell division; Cells; Cellular biology; Complex; Data; Development; Dimerization; Disabled Persons; Energy Transfer; Enzymes; Event; Fluorescence Microscopy; Goals; Health; Human; Image; Immune; Immune response; Immunity; Immunologic Surveillance; In Vitro; Individual; Infection; Knowledge; Life; Ligands; Macromolecular Complexes; Mediating; Membrane; Memory; Molecular; Molecular Biology Techniques; Molecular Target; Peptide/MHC Complex; Phosphotransferases; Positioning Attribute; Process; Publishing; Reagent; Receptor Signaling; Recruitment Activity; Reporting; Side; Signal Transduction; Structure; Sum; Surface; Surface Antigens; Surveys; System; T-Cell Development; T-Cell Receptor; T-Lymphocyte; Tertiary Protein Structure; Testing; Transplantation; Vaccines; Work; base; biophysical properties; cytokine; design; extracellular; handicapping condition; in vivo; insight; mouse model; mutant; novel; pathogen; prevent; research study; response; sensor; spatial relationship

DESCRIPTION (provided by applicant): The TCR-CD3 complex, CD4, and CD28 are vital checkpoint molecules that allow T cells to survey for antigens and activation induced molecules on the surfaces of antigen presenting cells (APCs). They then transfer this antigen- and APC-specific information to the T cell's intracellular signaling apparatus. Ultimately, this informatio directs the T cell fate decisions that drive development, activation, differentiation, and the execution of effector functions. The fundamental importance of these molecules to immune surveillance and human health has resulted in several studies regarding their structure and function over the past 25+ years. As a result, much is now known about their individual structures, their interactions with their respective ligands in isolation, and the signaling cascads that result from these interactions. But, we have yet to determine how they fit and work together as components of the molecular machinery that drives T cell fate decisions and this has prevented us from understanding how this molecular machinery, as a whole, executes its functions. Further, this lack of knowledge has handicapped our ability to strategically target this molecular machinery with reagents designed to either enhance responses to vaccines, tumor, or pathogens, or to attenuate responses to transplants or auto-antigens. Our goal is to deconstruct, understand, and ultimately manipulate the form and function of this complex macromolecular machine. To this end, we will: 1) determine how antigen-specific information is relayed across the membrane by the TCR to the intracellular signaling domains of the CD3 subunits; 2) determine how these signaling subunits are positioned in close proximity with the enzymes that modify them; and 3) determine how the surfaces that stabilize the architecture of this higher order machinery influence CD4+ T cell fate decisions in vivo. We have developed a novel experimental platform that combines classic biochemical and molecular biology techniques with modern polycistronic retroviral systems, kinase- based dimerization assays, and live cell fluorescent video imaging (including the use of total internal reflection fluorescence microscopy (TIRFM) and Forster Resonance Energy Transfer (FRET)), to take a highly controlled reductionist approach to addressing Aim 1 and 2. In addition, we are building novel mouse model systems to accomplish Aim 3. Specifically we will study the surfaces that we have already identified as mediating TCR- CD3 complex stability and TCR dimerization to determine how these interactions, which are at the core of the higher-order macromolecular machinery that transfers pMHC-specific information from the outside to the inside of a cell, influence T cell fate decisions in vivo. Altogether, these experiments will yield important insights into the molecular mechanisms that underlie CD4+ T cell fate decisions and identify potential targets for the development of translational immune-modulating reagents.

描述（由申请人提供）：TCR-CD3复合物、CD4和CD28是重要的检查点分子，允许T细胞在抗原呈递细胞（apc）表面调查抗原和激活诱导分子。然后它们将抗原和apc特异性信息传递给T细胞的细胞内信号装置。最终，这些信息指导T细胞的命运决定，驱动发育、激活、分化和执行效应功能。在过去的25年里，这些分子对免疫监测和人类健康的根本重要性导致了一些关于它们的结构和功能的研究。因此，现在对它们的个体结构、它们与各自配体的相互作用以及由这些相互作用产生的信号级联已经有了很多了解。但是，我们还没有确定它们作为驱动T细胞命运决定的分子机制的组成部分是如何配合和一起工作的，这阻碍了我们理解这个分子机制作为一个整体是如何执行其功能的。此外，这种知识的缺乏阻碍了我们在战略上瞄准这一目标的能力