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: 9169832
• 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/9169832
• 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; Gene Targeting; Genes; Host Defense; ITGAX gene; Immune; Immune response; Immunity; Immunization; 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; Phenotype; Play; Production; Regulation; Research; Resistance; Role; Second Messenger Systems; Severities; Signal Transduction; Site; Stimulus; T-Lymphocyte; Testing; Trichuris; Wild Type Mouse; Work; antimicrobial; base; enteric pathogen; immunopathology; innovation; insight; knock-down; mouse model; mucosal site; pathogen; physiologic model; promoter; response; second messenger; 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 我们在CD11C+树突状细胞（DC）中发现了一个新的途径，该途径控制T辅助细胞的分化 进入Th17和Th2谱系。 在粘膜部位的免疫防御和免疫病理学的差异指示中起着关键作用 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 综合，我们已经产生了两个强大的新生理模型 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）。 GNAI2CD11C小鼠俯卧Th17 异常。这些发现使我们假设：i） 创建一个Pro-Th17（高训练营）或Pro-Th2（低营）DC表型； DC中没有气体与GAI导致不同粘膜器官的免疫反应性差异； DC中的差异cAMP调节可以被用作创新的免疫调节性药理学 治疗与Th17和Th2相关的病理和相关感染的策略。 具有互补专业知识的纪律团队，以四个特定目标来测试假设 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，以及自发的粘膜免疫病理学。 GA和GAI在经典DC1（CDC1）和CDC2的开发和功能上的作用将探索您 DC中气体和GAI在控制炎症表型中的功能 结肠炎。 SA4将定义DC控制的Th17/Th2极化的气体和GAI依赖性介体。 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， 该提案将进行系统测试。 依赖营地的免疫防御和粘膜部位的免疫病也会形成您 针对DC的营地功能的创新免疫治疗策略的基础。 推进基本免疫学研究的可能性，并满足调节的未满足医疗需求 破坏性粘膜免疫反应和针对肠道病原体的保护性反应。