Sweet receptor (T1R2/3) signaling in the upper airway and regulation of immunity

上呼吸道中的甜味受体 (T1R2/3) 信号转导和免疫调节

• 批准号: 9284440
• 负责人: Robert J. Lee
• 金额: $ 16万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9284440
• 关键词: ASIC channel; Acidity; Acute; Affect; Alpha Cell; Amino Acids; Anti-Bacterial Agents; Antibodies; Artificial Sweeteners; Bacteria; Bacterial Infections; Bicarbonates; Biochemical; Biochemistry; Biological Assay; Breathing; Cell Culture Techniques; Cell physiology; Cells; Chronic; Consumption; Coupled; Coupling; Cyclic AMP; Data; Diabetes Mellitus; Effectiveness; Epithelial Cells; Epithelium; Functional disorder; Future; G-substrate; GTP-Binding Proteins; Genetic; Genetic Polymorphism; Genotype; Glucose; Goals; Health; Homo; Human; Immunity; Immunofluorescence Immunologic; Immunofluorescence Microscopy; Infection; Innate Immune Response; Irrigation; Lead; Ligands; Link; Measurement; Mediating; Microbial Biofilms; Modeling; Mus; Natural Immunity; Nitric Oxide; Nose; Pathway interactions; Patients; Pattern; Peptide Signal Sequences; Pharmacology; Physiological; Play; Predisposition; Production; Protein Isoforms; Publishing; Regulation; Research; Respiratory Tract Infections; Role; Signal Pathway; Signal Transduction; Signal Transduction Pathway; T1R receptor; T2R taste receptors; TRPM5 gene; Taste Buds; Taste Perception; Techniques; Testing; Therapeutic; Time; Tissues; Tongue; Upper Respiratory Infections; Western Blotting; airway epithelium; airway surface liquid; alpha-gustducin; antimicrobial peptide; bacterial metabolism; bactericide; cell type; chronic rhinosinusitis; defense response; experimental study; high throughput screening; in vivo; inhibitor/antagonist; insight; live cell imaging; novel therapeutics; prevent; public health relevance; quorum sensing; rat Gnat3 protein; receptor; response; sugar; sweet receptor; sweet taste perception; targeted treatment; taste transduction

 DESCRIPTION (provided by applicant): We recently discovered that human sinonasal solitary chemosensory cells (SCCs) express T2R bitter taste receptors that, when activated, stimulate Ca2+ -driven secretion of antimicrobial peptides (AMPs) from surrounding epithelial cells, playing an important role in innate immunity. We hypothesize that, in vivo, SCCs use T2Rs to respond to bitter bacterial products by activating AMP secretion. Furthermore, SCC T2R-mediated Ca2+ responses are inhibited the T1R3 sweet receptor in response to artificial sweeteners, sweet D-amino acids (produced by many bacteria), and physiologically-relevant glucose concentrations in the airway surface liquid (ASL). This inhibition may occur through T1R-activation of cAMP signaling. Immunofluroescence suggests that T2R and T1R3 receptors are expressed within the same SCCs, likely coupled to different intracellular signaling pathways. We hypothesize that T1R-mediated inhibition of T2Rs exists to partially inhibit AMP release during times of relative health, as complete secretion and depletion of AMPs may leave the epithelium excessively vulnerable. During acute infection, bacteria may consume available ASL glucose, decreasing glucose concentration and deactivating T1R inhibition of T2Rs, allowing AMP release. The ability of T1Rs to inhibit AMP secretion is also modulated by airway surface liquid (ASL) pH, which may represent a host adaptive mechanism to counter D-amino acid production by bacteria. While we have defined much of human SCC T2R signaling, this T1R pathway is unknown. Our central hypothesis is that T1R2 and/or T1R3 sweet receptor subunits and T2Rs, expressed in the same sinonasal SCCs, are coupled to different intracellular signaling pathways. To test this, we will take sinonasal tissue explants and differentiated primary cultures of human and mouse sinonasal cells and (1) use immunofluorescence to examine T1R distribution in human SCCs, (2) identify T1R signal transduction pathway(s) in SCCs, including deriving pure or enriched cultures of mouse SCCs to biochemically characterize SCC T1R signaling, and (3) examine the mechanism of ASL pH regulation of SCC T1R signaling. We will also genotype human Tas1R2 and Tas1R3 polymorphisms to determine their influence on T1R signaling in SCCs. The goal of these aims is to identify the localization and signal transduction of sinonasal T1R receptors, which may be very important to developing new therapies for respiratory infections. ASL glucose is abnormally elevated in certain conditions such as diabetes mellitus and chronic rhinosinusitis, both of which often involve chronic respiratory infections. Excessive ASL glucose may overly inhibit T2R-mediated innate immunity, making T1R antagonists (eg, lactisole) therapeutic options to restore innate immune responses in certain patients. Moreover, if Tas1R2/3 polymorphisms play an important role in sinonasal T1R function, then future studies could reveal that Tas1R genetics and/or taste testing may be useful for making predictions about susceptibility to upper respiratory infections and/or the effectiveness of T1R-targeted therapeutics.

 描述（由适用提供）：我们最近发现，人类鼻窦固体化学感应细胞（SCCS）表达T2R苦味接收器，当激活时，刺激Ca2+驱动的抗菌辣椒（AMPS）的分泌，来自周围上皮细胞，在先天性的免疫史中起重要作用。我们假设在体内，SCC使用T2RS通过激活AMP分泌来对苦细菌产物做出反应。此外，SCC T2R介导的Ca2+反应因人造甜味剂，甜D-氨基酸（由许多细菌产生）以及在气动表面液体（ASL）中的物理相关的葡萄糖浓度而抑制T1R3甜受体。这种抑制可能通过cAMP信号传导的T1R激活而发生。免疫荧光表明T2R和T1R3受体在同一SCC中表达，可能与不同的细胞内信号通路偶联。我们假设T1R介导的T2R抑制是在相对健康时期部分抑制AMP释放的抑制作用，因为AMP的完全分泌和耗竭可能会使上皮非常脆弱。在急性感染期间，细菌可能会消耗可用的ASL葡萄糖，降低葡萄糖浓度并停用T2RS的T1R抑制，从而释放AMP。 T1RS抑制AMP分泌的能力也受气道表面液体（ASL）pH的调节，这可能代表了通过细菌对抗D-氨基酸的宿主自适应机制。尽管我们已经定义了大部分人类SCC T2R信号传导，但该T1R途径尚不清楚。我们的中心假设是，在同一鼻窦SCC中表达的T1R2和/或T1R3甜受体亚基和T2RS耦合到不同的细胞内信号传导途径。 To test this, we will take sinonasal tissue explants and differentiated primary cultures of human and mouse sinonasal cells and (1) use immunofluorescence to examine T1R distribution in human SCCs, (2) identify T1R signal transfer pathway(s) in SCCs, including deriving pure or enriched cultures of mouse SCCs to biochemically characterize SCC T1R signaling, and (3) examine the mechanism of ASL pH regulation SCC T1R信号传导。我们还将基因型人TAS1R2和TAS1R3多态性确定它们对SCC中T1R信号的影响。这些目的的目的是确定Sinonasal T1R受体的定位和信号传递，这对于开发新的呼吸道感染疗法可能非常重要。在某些情况下，例如糖尿病和慢性鼻炎，ASL葡萄糖基本上升高，两者通常都涉及慢性呼吸道感染。过度的ASL葡萄糖可能过度抑制T2R介导的先天免疫学，从而使T1R拮抗剂（例如，乳酸）治疗方案恢复某些患者的先天免疫反应。此外，如果TAS1R2/3多态性在Sinonasal T1R功能中起重要作用，那么未来的研究可以表明，TAS1R遗传学和/或味觉测试可能有助于预测对上呼吸道感染的易感性和/或T1R靶向治疗的有效性。

项目成果

Plant flavones enhance antimicrobial activity of respiratory epithelial cell secretions against Pseudomonas aeruginosa.

• DOI: 10.1371/journal.pone.0185203
• 发表时间: 2017
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Hariri BM;McMahon DB;Chen B;Adappa ND;Palmer JN;Kennedy DW;Lee RJ
• 通讯作者: Lee RJ

Taste receptors in the upper airway.

• DOI: 10.1016/j.wjorl.2018.02.004
• 发表时间: 2018-03
• 期刊: World journal of otorhinolaryngology - head and neck surgery
• 作者: Freund JR;Lee RJ
• 通讯作者: Lee RJ