RV-Mediated Mechanisms of Neutrophil Motility /Inflammat

RV 介导的中性粒细胞运动/炎症机制

• 批准号: 7151331
• 负责人: Anna Huttenlocher
• 金额: $ 18.13万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7151331
• 关键词: asthma; calpain; cell adhesion; cell motility; chemotaxis; cooperative study; fluorescence; genetically modified animals; host organism interaction; human subject; inflammation; laboratory mouse; microfluidics; molecular /cellular imaging; molecular pathology; neutrophil; pathologic process; patient oriented research; respiratory infections; respiratory system; respiratory virus; rhinovirus; tumor necrosis factor alpha; virus infection mechanism

The inflammatory response induced by rhinovirus is characterized by the predominance of airway neutrophils that correlates with the severity of asthma exacerbation. Despite considerable recent evidence that supports the importance of neutrophils in the pathogenesis of asthma, there is limited understanding of how rhinovirus modulates neutrophil function. The long-term goal of this proposal is to characterize the signaling mechanisms by which respiratory viral infections induce neutrophil motility and recruitment to the airway, and to identify novel therapeutic targets that limit viral-induced inflammatory responses. Substantial evidence suggests that rhinovirus infections induce neutrophilic inflammation indirectly by promoting the release of inflammatory mediators from airway epithelial cells. We now have exciting new data that indicate that rhinovirus 16 also has direct effects on neutrophil signaling and motility. With our established expertise in live fluorescent imaging and recently developed novel technology to analyze chemotaxis using microfluidics, we are uniquely positioned to test the following hypothesis. We propose that rhinovirus, by both indirect and direct interactions with neutrophils, modulates signaling pathways critical for neutrophil migration and chemotaxis, and thereby affects the recruitment and retention of neutrophils in the airway. We propose the following Specific Aims: I. Elucidate the mechanisms of neutrophil chemotaxis and recruitment to the airway in response to respiratory viral infection. Calpain inhibition blocks neutrophil chemotaxis to IL-8 in vitro. Using both in vitro and in vivo approaches with transgenic mouse models in collaboration with Project IV, we propose to characterize how calpains regulate neutrophil chemotaxis and inflammatory recruitment in response to respiratory viral infection in vivo. II. Dissect the molecular mechanisms by which rhinovirus modulates TNFalpha-mediated neutrophil function. TNFalpha promotes a stop signal that triggers neutrophil adhesion and inhibits cell migration. Our recent studies indicate that rhinovirus perturbs TNFalpha-mediated effects. In addition, preliminary data indicate that rhinovirus may affect neutrophil function directly via activation of ERK and p38 MARK pathways. In collaboration with Project II and V, we now propose to dissect the molecular mechanisms by which rhinovirus modulates TNFalpha-mediated neutrophil adhesion and signaling. III. Examine the effect of rhinovirus on neutrophil motility and chemotaxis. Preliminary findings indicate that rhinovirus directly induces neutrophil random motility and reduces chemotactic migration through an ICAM-1- dependent pathway.. Using time lapse microscopy, we now propose to dissect the mechanisms by which rhinovirus modulates neutrophil migration and chemotaxis, and in collaboration with Project I determine if these mechanisms are different in patients susceptible to rhinovirus-induced asthma exacerbation.

鼻病毒引起的炎症反应以气道炎症反应为主。 中性粒细胞与哮喘恶化的严重程度相关。尽管最近有大量证据 尽管支持中性粒细胞在哮喘发病机制中的重要性，但人们对 鼻病毒如何调节中性粒细胞功能。该提案的长期目标是描述 呼吸道病毒感染诱导中性粒细胞运动的信号机制 招募到气道，并确定限制病毒诱导的新治疗靶点 炎症反应。大量证据表明鼻病毒感染可诱发中性粒细胞 通过促进气道上皮细胞释放炎症介质来间接抑制炎症。我们 现在有令人兴奋的新数据表明鼻病毒 16 也对中性粒细胞信号传导有直接影响 动力。凭借我们在实时荧光成像方面成熟的专业知识和最近开发的新技术 为了使用微流体分析趋化性，我们具有独特的优势来检验以下假设。我们 提出鼻病毒通过与中性粒细胞间接和直接相互作用来调节 对中性粒细胞迁移和趋化性至关重要的信号通路，从而影响 气道中中性粒细胞的募集和保留。我们提出以下具体目标： I. 阐明中性粒细胞趋化和募集至气道的机制 呼吸道病毒感染。体外钙蛋白酶抑制可阻断中性粒细胞对 IL-8 的趋化性。两者同时使用 与 Project IV 合作使用转基因小鼠模型进行体外和体内方法，我们建议 描述钙蛋白酶如何调节中性粒细胞趋化性和炎症募集以响应 体内呼吸道病毒感染。二.剖析鼻病毒调节的分子机制 TNFα介导的中性粒细胞功能。 TNFα 促进停止信号，触发中性粒细胞粘附并 抑制细胞迁移。我们最近的研究表明鼻病毒会干扰 TNFα 介导的作用。在 此外，初步数据表明鼻病毒可能通过激活ERK直接影响中性粒细胞功能 和 p38 MARK 途径。与项目 II 和 V 合作，我们现在建议剖析分子 鼻病毒调节 TNFα 介导的中性粒细胞粘附和信号传导的机制。三．检查 鼻病毒对中性粒细胞运动和趋化性的影响。初步调查结果表明 鼻病毒通过 ICAM-1- 直接诱导中性粒细胞随机运动并减少趋化迁移 依赖途径..使用延时显微镜，我们现在建议剖析其机制 鼻病毒调节中性粒细胞迁移和趋化性，并与 Project I 合作确定是否 这些机制在易受鼻病毒引起的哮喘恶化影响的患者中是不同的。