Mechanisms of tunable posttranslational control of T-cell homeostasis and tolerance

T 细胞稳态和耐受性的可调节翻译后控制机制

基本信息

批准号：
10165484
负责人：
Stanley Adoro
金额：
$ 44.6万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-07 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10165484
关键词：
Ablation Address Affinity Alleles American Animal Genetics Animal Model Autoimmune Autoimmune Diseases BCL2 gene Biochemical Bone Marrow Bone Marrow Cells Carrier Proteins Cause of Death Cell Survival Cell physiology Cells Charge Child Chimera organism Client Complex Coupled Coupling Cyclic AMP-Dependent Protein Kinases Data Defect Deubiquitinating Enzyme Development Disease Energy Metabolism Enzymes Genes Genetic Genetic Models Genomics Health Homeostasis Human IL7 gene Immunity Immunologic Deficiency Syndromes Impairment Inflammation Interruption Knowledge Laboratories Level of Evidence Ligands Link Location Lysine Maintenance Mediating Mediator of activation protein Metabolic Metabolism Modeling Multivesicular Body Mus Mutation Pathologic Pathway interactions Peripheral Phenotype Phosphorylation Phosphotransferases Positioning Attribute Process Protein Family Proteins Proteomics Proto-Oncogene Protein c-kit Receptor Signaling Regulation Resolution Resources Role Self Tolerance Serine Signal Pathway Signal Transduction Sorting - Cell Movement Structure System T cell regulation T-Cell Development T-Cell Receptor T-Lymphocyte Testing Therapeutic Tissues Transgenic Animals Translating Transmembrane Transport USP8 gene Ubiquitin Ubiquitination Woman Work autoreactive T cell base calmodulin-dependent protein kinase II cellular targeting central tolerance cost design effective therapy human disease innovation insight metabolomics multicatalytic endopeptidase complex mutant novel pathogen prevent programs protein expression reconstitution recruit thymocyte

项目摘要

Summary Defects in the stringently regulated processes that generate and maintain the diverse and self-tolerant pool of T-cells responsible for immunity cause very debilitating human autoimmune and immunodeficiency diseases. Despite decades of evolving therapies, autoimmune diseases still rank among the leading causes of death especially in women and children in the US alone where more than 23 million people are afflicted, at a cost that exceeds $100 billion annually to the economy. As dysfunctional T-cell development and homeostasis frequently underlie autoimmune disease states, development of more effective therapies against these diseases will benefit from resolving major knowledge gaps of the cellular factors and pathways that enable T- cell homeostasis. For example, proteasome-dependent mechanisms control the activity of proteins that mediate survival, metabolism and signal transduction in T-cells but how key homeostatic signals from the T-cell receptor (TCR) and interleukin (IL)-7 are coupled to the ubiquitination machinery is still poorly understood. We recently discovered that the Charged Multivesicular Body Protein-5 (CHMP5) functions as an “adaptor” during T-cell development to recruit deubiquitinating enzymes that promote client protein stability. New evidence from our laboratory shows that CHMP5 expression is stringently controlled by TCR and IL-7 signals, and that deletion of CHMP5 in peripheral T-cells impaired their homeostasis and was associated with a fully penetrant multi-organ autoimmune condition. Thus, leveraging animal models that allow precise tracking of CHMP5 mutant T-cells, in this proposal we will test the hypothesis that CHMP5 nucleates a critical posttranslational node by which homeostatic signals are integrated to the stability of protein mediators of T-cell survival and tolerance, situating it as a tunable and potential target for modulating T-cells in disease. In Aim I, we will determine how CHMP5 controls energy metabolism and prosurvival proteins integral to peripheral T-cell survival and function. In Aim 2, we will elucidate the mechanism of differential CHMP5 stabilization by TCR and IL-7 signals, especially their ability to induce serine phosphorylations that stabilize CHMP5 protein. Additionally, as deletion of the deubiquitinase USP8 depletes CHMP5 proteins in T-cells, we will define the basis of the USP8-CHMP5 interaction. Disrupting this interaction can potentially be utilized to therapeutically deplete T-cell CHMP5. To date, how TCR signal thresholds are translated into thymocyte positive and negative selection remains unclear. Thus, building on evidence that CHMP5 is stabilized by low affinity TCR ligands but degraded by high affinity signals, in Aim 3, we will test the novel paradigm that differential CHMP5 protein stabilization is a thymocyte mechanism to establish central tolerance. These studies will yield insights into long-standing questions on T-cell homeostasis and have the potential to uncover new posttranslational vulnerabilities that can be exploited to therapeutically modulate T-cells in disease especially as dysregulation of the human 9p13.3 chromosomal region location of CHMP5 gene is linked with diseases in multiple tissues.

概括在严格监管的过程中的缺陷，产生和维护潜水员和自耐池的缺陷负责免疫学的T细胞会导致人类自身免疫性和免疫缺陷疾病非常衰弱。尽管经过数十年的疗法，自身免疫性疾病仍然是死亡的主要原因之一特别是在美国仅在美国的妇女和儿童中，有超过2300万人遭受了折磨经济每年超过1000亿美元。作为功能失调的T细胞开发和稳态经常是自身免疫性疾病状态的基础，开发对这些疾病的更有效疗法疾病将受益于解决能够t-的细胞因素和途径的主要知识差距细胞稳态。例如，蛋白酶体依赖性机制控制蛋白质的活性介导T细胞中的存活率，代谢和信号转移，但如何来自T细胞的关键稳态信号受体（TCR）和白介素（IL）-7与泛素化机制耦合仍然很少了解。我们最近发现，带电的多质体蛋白-5（CHMP5）在 T细胞开发以募集促进客户蛋白稳定性的酶的去泛素化酶。来自的新证据我们的实验室表明，CHMP5表达受TCR和IL-7信号的严格控制，并且外围T细胞中CHMP5的删除损害了其稳态，并且与完全渗透剂有关多器官自身免疫性状况。那就是利用允许精确跟踪CHMP5的动物模型突变体T细胞，在此提案中，我们将检验以下假设：CHMP5核核化合物关键后翻译后在将体内稳态信号集成到T细胞存活蛋白介质的稳定性的节点和容忍度，将其视为调节疾病中T细胞的可调节和潜在的靶标。在目标一世中我们将确定CHMP5如何控制能量代谢和外周T细胞不可或缺的蛋白质生存和功能。在AIM 2中，我们将阐明TCR和 IL-7信号，尤其是它们诱导稳定CHMP5蛋白的丝氨酸磷酸化的能力。此外，随着去偶素酶USP8的缺失耗尽T细胞中的CHMP5蛋白，我们将定义 USP8-CHMP5相互作用的基础。破坏这种相互作用可能会用于治疗耗尽T细胞CHMP5。迄今为止，如何将TCR信号阈值转化为胸腺细胞正和阴性选择仍然不清楚。这是基于证据表明CHMP5通过低亲和力TCR配体稳定的证据，但在高亲和力信号下降解，在AIM 3中，我们将测试新的范式，即差异CHMP5蛋白稳定是建立中心耐受性的胸腺细胞机制。这些研究将产生对关于T细胞稳态的长期问题，有可能发现新的翻译后可以探索治疗的脆弱性，以调节疾病的T细胞，尤其是在失调的情况下 CHMP5基因的人9p13.3染色体区域的位置与疾病多次有关。