Function of NLRP3 in regulatory T cell-mediated control of intestinal homeostasis

NLRP3 在调节性 T 细胞介导的肠道稳态控制中的功能

• 批准号: 10748891
• 负责人: RASIKA PATKAR
• 金额: $ 4.03万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10748891
• 关键词: Ablation; Affect; Anti-Inflammatory Agents; Antigens; Autoimmune; Bacterial Infections; Biological; Bone Marrow; CASP1 gene; CD3 Antigens; Caspase; Cell physiology; Cells; Cellular Indexing of Transcriptomes and Epitopes by Sequencing; Cellular biology; Chimera organism; Chronic; Citrobacter rodentium; Complex; Cytoplasm; Data; Development; Disease; Disease model; Enteral; Exhibits; FOXP3 gene; Food; Frequencies; Future; Genes; Homeostasis; Human; IL17 gene; IL18 gene; Immune; Immune response; Immunity; Infection; Inflammasome; Inflammation; Inflammatory; Inflammatory Bowel Diseases; Interleukin-1; Interleukin-1 beta; Intestinal Diseases; Intestines; Knockout Mice; Lymphoid; Measures; Mediating; Microbe; Modeling; Molecular; Multiprotein Complexes; Mus; Natural Immunity; Nature; Pathologic; Pathway interactions; Physiological; Play; Production; Proteins; Regulation; Regulatory T-Lymphocyte; Reporting; Role; Sorting; System; T cell differentiation; T cell response; T-Lymphocyte; T-Lymphocyte Subsets; Testing; Therapeutic; Tissues; Transcript; adaptive immunity; commensal microbes; constitutive expression; cytokine; effective therapy; gain of function; gut inflammation; immunoregulation; insight; intestinal homeostasis; loss of function; mouse model; novel; response; transcription factor; transcriptome sequencing

Project Summary The inflammasomes are cytoplasmic multi-protein complexes that can sense and be activated by microbes or tissue damage, which then leads to the activation of caspase-mediated inflammatory pathways involving the release of cytokines IL-1β and IL-18. Although the pro-inflammatory role of inflammasomes have been well established in innate immune cells, recently, several studies have uncovered a role for different inflammasome components in regulating many different T cell responses, a key part of adaptive immunity. Specifically, a subset of T cells called regulatory T cells (Tregs), which are known for their ability to suppress immune responses and inflammation, were shown to be affected by their cell intrinsic inflammasome components. Even though the critical role of Tregs in establishing tolerance to a wide range of innocuous foreign antigens from commensal microbes and food in the gut has long been well-recognized, the function of the NLRP3 inflammasome in Treg-mediated control of intestinal homeostasis remains an open question. Based on preliminary data, it was hypothesized that NLRP3/inflammasome could serve as an integral determinant in controlling Treg biology and that induction of NLRP3 in intestinal Tregs would be specifically required for their control of Th17 responses in the intestine. To test this hypothesis, the first aim will elucidate the function of NLRP3 in controlling Treg biology in the gut in heath and disease using both loss-of-function and gain-of- function approaches through employing two novel mouse models that have been recently generated in the lab: mice with Treg-specific deletion of NLPR3 and mice with Treg-specific expression of constitutively active NLRP3. Two different Th17-dependent disease models: anti-CD3 induced intestinal inflammation and Citrobacter rodentium infection model will be employed. As such, the biological impact of NLRP3 depletion or constitutive activation in Tregs on the other immune cells in the intestinal system under both physiological and pathological conditions will be elucidated. In the second aim, the molecular mechanisms underlying NLRP3- mediated control of Treg biology will be investigated. First, as IL-1b, a component of the NLRP3/inflammasome pathway was also found to be selectively induced in intestinal Tregs under inflammation, I will determine the potential role of Treg-derived IL-1b in controlling intestinal homeostasis. Next, the potential involvement of inflammasome-independent vs. –dependent mechanism underlying NLRP3-mediated Treg biology will also be examined. Finally, as the heterogeneous nature of Tregs is now well appreciated, Cellular Indexing of Transcriptomes and Epitopes by Sequencing (CITE-seq) studies will be conducted to determine if there is a specific subset of Tregs that expresses NLRP3 or whether NLRP3 induction is a common feature for all intestinal Tregs under inflammation. Collectively, this study will provide mechanistic insights into the underappreciated anti-inflammatory role of NLRP3 in intestinal Tregs and will undoubtedly facilitate the development of future therapeutics for inflammatory bowel disease and other human intestinal disorders.

项目摘要 炎性症是细胞质多蛋白质复合物，可以被微生物或 组织损伤，然后导致caspase介导的炎症途径的激活，涉及 细胞因子IL-1β和IL-18的释放。尽管炎症的促炎作用很好 最近在先天免疫核管上建立的一些研究发现了不同炎症体的作用 确定许多不同T细胞反应的组成部分，这是适应性免疫学的关键部分。具体而言， T细胞的子集称为调节T细胞（Tregs），它们以抑制免疫的能力而闻名 反应和炎症显示出受其细胞内在炎症体成分的影响。甚至 尽管Tregs在建立对从 肠道中的共生微生物和食物长期以来已经得到很好的认识，NLRP3的功能 Treg介导的肠内稳态控制中的炎性体仍然是一个悬而未决的问题。基于 初步数据，假设NLRP3/炎症体可以作为不可或缺的确定源 控制Treg生物学和肠Treg中NLRP3的诱导是特别需要的 控制肠中Th17的反应。为了检验这一假设，第一个目标将阐明 NLRP3在使用功能丧失和 - 通过采用最近在实验室中生成的两种新型小鼠模型来实现功能方法： NLPR3的Treg特异性缺失和具有组成性活性的Treg特异性表达的小鼠 nlrp3。两种不同的Th17依赖性疾病模型：抗CD3诱导肠道注射和 将聘请柠檬酸啮齿动物感染模型。因此，NLRP3耗竭的生物学影响或 在生理和 病理条件将被阐明。在第二个目标中，NLRP3-的分子机制 将研究对Treg生物学的介导的控制。首先，作为IL-1B，NLRP3/炎症组的组成部分 还发现在注射下肠Treg中选择性诱导途径，我将确定 Treg衍生的IL-1B在控制肠内稳态中的潜在作用。接下来，潜在的参与 炎症体无关与 - 依赖性机制NLRP3介导的Treg生物学的依赖性机制也将是 检查。最后，由于Treg的异质性现在得到了很好的赞赏，因此细胞索引的索引 通过测序（Cite-Seq）研究将进行转录组和表位，以确定是否存在 表达nlrp3的treg的特定子集还是NLRP3感应是所有人的常见特征 在炎症下肠Treg。总的来说，这项研究将提供有关机械的见解 NLRP3在肠Tregs中的抗炎作用不足，无疑会准备 开发未来炎症性肠病和其他人类肠道疾病的疗法。