Control of mucosal immunity by Gas- vs Gai-linked GPCR signaling in dendritic cells

树突状细胞中 Gas 与 Gai 连接的 GPCR 信号传导控制粘膜免疫

• 批准号: 9288124
• 负责人: Eyal Raz
• 金额: $ 46.11万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-06 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9288124
• 关键词: Address; Adjuvant; Adoptive Transfer; Age; Antigens; CD4 Positive T Lymphocytes; CREB1 gene; Cell Differentiation process; Citrobacter rodentium; Colitis; Coupled; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Dendritic Cells; Development; G Protein-Coupled Receptor Signaling; GTP-Binding Proteins; Gases; Gene Targeting; Genes; Helper-Inducer T-Lymphocyte; Host Defense; ITGAX gene; Immune; Immune response; Immunity; Immunization; Immunologics; Immunotherapeutic agent; In Vitro; Infection; Inflammation; Inflammatory disease of the intestine; Intestines; Knockout Mice; Link; Mediating; Mediator of activation protein; Medical; Microbe; Modeling; Mouse Strains; Mucosal Immune Responses; Mucosal Immunity; Mus; Organ; Pathology; Pathway interactions; Pharmacology; Phenotype; Play; Production; Recruitment Activity; Regulation; Research; Resistance; Role; Second Messenger Systems; Severities; Signal Transduction; Site; Stimulus; T-Lymphocyte; Testing; Trichuris; Wild Type Mouse; Work; antimicrobial; enteric pathogen; immunopathology; immunoregulation; innovation; insight; interdisciplinary approach; knock-down; mouse model; mucosal site; multidisciplinary; pathogen; physiologic model; promoter; response; small hairpin RNA

Project Summary We have uncovered a new pathway in CD11c+ dendritic cells (DC) that controls T helper cell differentiation into the Th17 and Th2 lineages. The pathway involves cyclic AMP (cAMP) and protein kinase A (PKA), and plays a key role in the differential induction of immune defense and immunopathology at mucosal sites. In this project, we will address the underlying mechanisms by focusing on signaling by the heterotrimeric (αβγ) GTP binding proteins, Gas (encoded by Gnas) and Gai (encode by Gnai2), which stimulate and inhibit cAMP synthesis, respectively. We have generated two powerful new physiologic models to explore cAMP functions in mucosal immune regulation, CD11c-specific conditional gene-targeted mice for Gnas (GnasCD11c, low cAMP) and Gai (Gnai2CD11c, high cAMP). We discovered that GnasCD11c mice are biased toward Th2, whereas Gnai2CD11c mice are prone to Th17, and that the two mouse strains display distinct mucosal immune abnormalities. These findings have led us to hypothesize that: I) Differential cAMP production in CD11c+ DC creates a pro-Th17 (high cAMP) or pro-Th2 (low cAMP) DC phenotypes; II) The imbalance of cAMP in the absence of Gas vs. Gai in DC results in differential immune reactivity in different mucosal organs; and III) Differential cAMP regulation in DC can be exploited pharmacologically as an innovative immune-modulatory strategy to treat Th17- and Th2-related pathologies and their related infections. We have assembled a multi- disciplinary team with complementary expertise to test these hypotheses in four Specific Aims. In Specific Aim 1 (SA1), we will assess the impact of Gas- and Gai-dependent signaling in DC on constitutive Th bias at different mucosal and systemic sites, and on spontaneous mucosal immunopathology. We will then evaluate the role of Gas and Gai on classical DC1 (cDC1) and cDC2 development and function. SA2 will explore the function of Gas and Gai in DC in controlling intestinal inflammation phenotypes in complementary models of colitis. SA3 will determine the importance of Gas and Gai in DC in antimicrobial host defense in the intestine, while SA4 will define Gas- and Gai- dependent mediators of DC-controlled Th17/Th2 polarization. Taken together, our discoveries in newly constructed Gnas∆CD11c and Gnai2CD11c mouse models have led to exciting and innovative hypotheses on the role of cAMP signaling in DC in orchestrating mucosal immune decisions, which will be systematically tested in this proposal. The results will yield new insight into the mechanisms of cAMP-dependent immune defense and immunopathology at mucosal sites. The findings will also form the basis for innovative immunotherapeutic strategies to target cAMP functions in DC. The project has a high likelihood of advancing basic immunological research, and addressing an unmet medical need in modulating destructive mucosal immune responses and in promoting protective responses against enteric pathogens.

项目摘要 我们发现了控制T辅助细胞分化的CD11C+树突状细胞（DC）中的新途径 进入TH17和TH2谱系。该途径涉及环状AMP（CAMP）和蛋白激酶A（PKA），以及 在粘膜部位的免疫防御和免疫病理学的差异诱导中起关键作用。在这个 项目，我们将通过关注异三聚体（αβγ）GTP的信号来解决潜在的机制 结合蛋白，气体（由GNA编码）和GAI（由GNAI2编码），刺激和抑制cAMP 分别合成。我们已经生成了两个强大的新生理模型，以探索营地功能 粘膜免疫调节，CD11C特异性条件基因针对GNA的小鼠（GNASCD11C，低cAMP） 和Gai（GNAI2CD11C，高训练营）。我们发现gnascd11c小鼠偏向TH2，而 GNAI2CD11C小鼠容易发生Th17，并且两种小鼠菌株显示出不同的粘膜免疫 异常。这些发现使我们假设：i）CD11C+ DC中的差异营地生产 创建Pro-Th17（高训练营）或Pro-Th2（低营）DC表型； ii）营地在 DC中没有气体与GAI的缺乏会导致不同粘膜器官的免疫反应性差异；和iii） DC中的差异cAMP调节可以作为创新的免疫调节探索 治疗Th17-和Th2相关病理及其相关感染的策略。我们已经组装了一个 具有完善专业知识的纪律团队，以四个特定目标来检验这些假设。在特定目标中 1（SA1），我们将评估DC中气体和GAI依赖性信号传导对本构偏见的影响 不同的粘膜和全身性部位，以及赞助粘膜免疫病理学。然后我们将评估 气体和GAI在经典DC1（CDC1）以及CDC2开发和功能中的作用。 SA2将探索 DC中气体和GAI在控制肠道注射表型中的功能 结肠炎。 SA3将确定DC在DC中的重要性 而SA4将定义DC控制的TH17/TH2极化的气体和依赖性介体。拍摄 一起，我们在新建的GNASΔCD11C和GNAI2CD11C鼠标模型中的发现导致了令人兴奋的 以及关于DC在策划粘膜免疫决策中的cAMP信号作用的创新假设， 这将在本提案中进行系统测试。结果将产生有关机制的新见解 粘膜部位依赖营地的免疫防御和免疫病理学。这些发现也将形成 创新的免疫治疗策略的基础，以针对DC中的CAMP功能。该项目高 提高基本免疫学研究的可能性，并解决调制未满足的医疗需求 破坏性的粘膜免疫反应并促进针对肠道病原体的保护反应。