ACUTE AIRWAY EFFECTS OF TLR7 AND TLR8 STIMULATION IN HEALTH AND DISEASE

TLR7 和 TLR8 刺激对健康和疾病的急性气道影响

• 批准号: 8272435
• 负责人: David B Jacoby
• 金额: $ 43.54万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2017-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8272435
• 关键词: Abbreviations; Acids; Acute; Affect; Agonist; American; Antigens; Antiviral Agents; Arginine; Asthma; Bathing; Bronchoconstriction; Bronchodilation; Calcium; Cavia; Cells; Citrates; Contracts; Copper; Cyclooxygenase Inhibitors; Data; Disease; Dose; Electric Stimulation; Esters; Fluorescein; Functional disorder; Genes; Glutathione; Health; Histamine; Human; Imiquimod; Immune response; In Vitro; Indomethacin; Inflammatory; Lead; Left; Mediating; Modeling; Mus; Muscle; Muscle relaxation phase; NG-Nitroarginine Methyl Ester; Nature; Nerve; Neurons; Nitric Oxide; Nitric Oxide Donors; Nitric Oxide Synthase; Nitroarginine; Pathway interactions; Pharmaceutical Preparations; Production; Prostaglandin Production; Prostaglandins; RNA; Reagent; Receptor Signaling; Recruitment Activity; Relative (related person); Relaxation; Role; Second Messenger Systems; Shortness of Breath; Signal Pathway; Smooth Muscle; Smooth Muscle Myocytes; Stimulus; TLR7 gene; TLR8 gene; Testing; Tissues; Toll-like receptors; Uridine; Vagus nerve structure; Viral; Virus; Virus Diseases; Wheezing; Work; adapter protein; airway hyperresponsiveness; airway inflammation; antagonist G; arginase; constriction; eosinophil; experience; human TLR7 protein; human TLR8 protein; in vivo; inhibitor/antagonist; large-conductance calcium-activated potassium channels; methacholine; neuroregulation; omega-N-Methylarginine; parainfluenza virus; paxilline; prevent; receptor; research study; respiratory smooth muscle; response; second messenger; sensitizing antigen; sildenafil; viral RNA

DESCRIPTION (provided by applicant): Viral single standed RNA is sensed by cells via toll-like receptor (TLR)-7 and TLR-8. We have recently shown that stimulating TLR-7 and TLR-8 relaxes airway smooth muscle and prevents broncho-constriction in response to a variety of stimuli. The effect is profound, and can lead to virtually complete relaxation of smooth muscle. We have demonstrated this effect in guinea pigs and mice, and in human airway tissues. TLR7 dependent broncho-dilation in guinea pigs and in human airways is mediated by production of nitric oxide, while TLR8 dependent broncho-dilation is not. Our preliminary data suggest that TLR8 mediated broncho-dilation is mediated by production of prostaglandins and opening of the large conductance, calcium activated potassium channel. We have also shown that both antigen sensitization and acute viral infection substantially impair TLR- dependent broncho-dilation. In this application, we propose three specific aims: Specific Aim #1. To A) use TLR7(-/-) mice, as well as newly generated TLR8(-/-) and TLR7(-/-)TLR8(-/-) mice, to more thoroughly investigate and establish the signaling pathways responsible for the effects of these receptors on airway neurons and smooth muscle, B) test whether these receptors signal through nitric oxide, prostaglandins, and the large conductance, calcium activated potassium channel (BKCa) in human airways in vitro, and C) explore the role of nitric oxide and prostaglandins and changes in intracellular calcium in rapid signaling by these receptors in primary cultures of human airway parasympathetic neurons and airway smooth muscle cells. Specific Aim 2: To test whether decreased TLR mediated broncho-dilation after antigen sensitization is mediated by decreased TLR7 and/or TLR8, testing signaling pathways in airway smooth muscle identified in Aim #1. Since these TLRs are on parasympathetic nerves, as well as on eosinophils recruited to the airway nerves, we will also test whether TLR7 and TLR8 change neural control in sensitized airways. SPECIFIC AIM #3: To test whether decreased TLR mediated broncho-dilation after viral infection is mediated by decreased TLR7 and/or TLR8 pathways, testing all second messenger signaling pathways in airway smooth muscle identified in aim one. We will also investigate the role of changes in parasympathetic function. The results of the experiments we propose will be important in establishing the potential of TLR7 AND TLR8 agonists as treatments for asthma and other airway diseases. In addition, because these receptors respond to viral RNA, understanding the effects of stimulating TLR7 receptors in the airways, as well as the loss of these effects in models of asthma, will help us understand the pathophysiology of virus induced asthma attacks. PUBLIC HEALTH RELEVANCE: Asthma affects 5 - 10% of Americans. The wheezing and shortness of breath that people with asthma experience is due to constrictions of the airways. We have recently found that drugs working through a receptor that normally recognizes viruses causes the airways to relax. In this project, we will study how these drugs relax the airways, and how this response may be damaged in asthma, to lay the groundwork to allow us to develop this class of drugs into asthma treatments.

描述（由申请人提供）：病毒单站RNA通过toll样受体(TLR)-7和TLR-8被细胞感知。我们最近的研究表明，刺激TLR-7和TLR-8可以放松气道平滑肌，防止支气管在各种刺激下收缩。效果是深远的，可以导致平滑肌几乎完全放松。我们已经在豚鼠和小鼠以及人类气道组织中证明了这种效果。豚鼠和人气道中TLR7依赖性支气管扩张是由一氧化氮的产生介导的，而TLR8依赖性支气管扩张则不是。我们的初步数据表明，TLR8介导的支气管扩张是通过前列腺素的产生和大导钙激活钾通道的打开介导的。我们还发现抗原致敏和急性病毒感染都严重损害TLR依赖性支气管扩张。在这个应用程序中，我们提出三个具体目标：A)利用TLR7（-/-）小鼠，以及新生成的TLR8（-/-）和TLR7（-/-)TLR8（-/-）小鼠，更深入地研究和建立这些受体对气道神经元和平滑肌作用的信号通路；B）在体外测试这些受体是否通过一氧化氮、前列腺素和大电导、钙活化钾通道（BKCa）发出信号；C)探讨一氧化氮和前列腺素以及细胞内钙的变化在人气道副交感神经细胞和气道平滑肌细胞原代培养中这些受体的快速信号传导中的作用。特异性目的2：检测抗原致敏后TLR介导的支气管扩张减少是否由TLR7和/或TLR8减少介导，测试目的1中确定的气道平滑肌信号通路。由于这些tlr位于副交感神经以及气道神经募集的嗜酸性粒细胞上，我们还将测试TLR7和TLR8是否会改变致敏气道的神经控制。目的3：检测病毒感染后TLR介导的支气管扩张减少是否由TLR7和/或TLR8通路减少介导，检测目的1中鉴定的气道平滑肌中所有第二信使信号通路。我们还将研究副交感神经功能变化的作用。我们提出的实验结果对于确定TLR7和TLR8激动剂治疗哮喘和其他气道疾病的潜力非常重要。此外，由于这些受体对病毒RNA有反应，了解刺激气道中TLR7受体的作用，以及这些作用在哮喘模型中的丧失，将有助于我们了解病毒诱导哮喘发作的病理生理学。