RV-Mediated Mechanisms of Neutrophil Motility /Inflammat

鼻病毒引起的炎症反应以呼吸道占优势为特征。 与哮喘加重程度相关的中性粒细胞。尽管最近有相当多的证据 这支持了中性粒细胞在哮喘发病机制中的重要性，但对 鼻病毒如何调节中性粒细胞功能。这项提案的长期目标是将 呼吸道病毒感染诱导中性粒细胞运动的信号机制 重新聚集到呼吸道，并确定限制病毒诱导的新的治疗靶点 炎症反应。大量证据表明，鼻病毒感染会导致中性粒细胞 间接炎症通过促进呼吸道上皮细胞释放炎症介质来实现。我们 现在有令人兴奋的新数据表明，鼻病毒16也直接影响中性粒细胞信号和 能动性。凭借我们在实时荧光成像方面的成熟专业知识和最近开发的新技术 要使用微流控技术分析趋化性，我们处于独特的位置来检验以下假设。我们 认为鼻病毒通过与中性粒细胞的间接和直接相互作用调节 对中性粒细胞迁移和趋化至关重要的信号通路，从而影响 中性粒细胞在呼吸道中的募集和滞留。我们提出了以下具体目标：一、 阐明中性粒细胞趋化和募集到呼吸道的机制 呼吸道病毒感染。在体外，钙蛋白酶抑制可阻断中性粒细胞对IL-8的趋化作用。在中同时使用 在与项目IV合作的转基因小鼠模型的体外和体内方法中，我们建议 描述钙调蛋白是如何调节中性粒细胞趋化和炎性募集的 体内呼吸道病毒感染。II.剖析鼻病毒调节的分子机制 肿瘤坏死因子α介导的中性粒细胞功能。肿瘤坏死因子α促进停止信号，触发中性粒细胞黏附和 抑制细胞迁移。我们最近的研究表明，鼻病毒干扰了肿瘤坏死因子α介导的作用。在……里面 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标记路径。在项目II和项目V的合作下，我们现在提议解剖分子 鼻病毒调节肿瘤坏死因子α介导的中性粒细胞黏附和信号转导的机制。三、审查 鼻病毒对中性粒细胞运动和趋化作用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 依赖路径..利用时间推移显微镜，我们现在建议剖析 鼻病毒调节中性粒细胞的迁移和趋化作用，并与项目I合作确定 这些机制在易患鼻病毒引起的哮喘恶化的患者中是不同的。

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.