Eosinophil integrins: interactions with VCAM and fibronectin

嗜酸性粒细胞整合素：与 VCAM 和纤连蛋白的相互作用

• 批准号: 6630926
• 负责人: DEANE Fremont MOSHER
• 金额: $ 19.62万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-01-05 至 2002-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6630926
• 关键词: G protein coupled receptor kinase; asthma; cell adhesion; cell line; cell migration; chemokine; chemotaxis; cytokine; eosinophil; extracellular matrix proteins; fibroblasts; fibronectins; human tissue; immunocytochemistry; immunologic assay /test; integrins; laboratory rat; leukocyte activation /transformation; monoclonal antibody; protein protein interaction; receptor binding; respiratory epithelium; tissue /cell culture; vascular cell adhesion molecule

(Applicant's Abstract) Eosinophils (EOS) preferentially accumulate in the airways of patients with asthma and contribute to airway hyperresponsiveness and airflow obstruction. The mechanisms for selective recuitment of EOS in asthma likely include: (a) priming of circulating EOS; (b) local upregulation of vascular cell adhesion molecule-1 (VCAM) by IL-4 and IL-13 Th-2 cytokines; (c) rolling and arrest of primed circulating EOS on VCAM-expressing pulmonary endothelial cells; (d) migration of arrested EOS into tissues in response to chemokines or other agonists of G-protein coupled receptors (GPCRs); (e) yet-to-be-defined chemotactic, chemokinetic, and chemostatic events in which EOS interact with VCAM and fibronectin (FN) in the bronchial wall; (f) movement of EOS into the airway lumen; and (g) prolonged survival of EOS of the airway wall and lumen driven by GM-CSF. EOS express 2 integrins that interact with VCAM and FN, alpha4beta1 and alpha4beta7, and a third, alphaDbeta2, that interacts with VCAM but not FN. VCAM and FN each exist as several differentially spliced forms. We hypothesize that the splice variations change the specificities and valencies of VCAM and FN for integrins on EOS and hence the responses of EOS to integrin ligation. Our aims are twofold. First, we will establish how interactions of alpha4beta1, alpha4beta7, and alphaDbeta2 with differentially spliced forms of VCAM and FN regulate adhesion, migration, and viability of EOS. Second, we will determine the distribution of various forms of VCAM and FN in normal and asthmatic airways. To accomplish these aims, we will (1) express differentially spliced forms of VCAM and FN that likely are encountered by EOS in transit from blood to airway; (2) prepare cell lines that replicate the expression patterns of integrins on blood and airway EOS and serve as models for EOS obtained from the circulation and lung before and after an asthma exacerbation; (3) characterize the abilities of blood EOS, airway EOS, and model cells to interact with splice forms of VCAM and FN in binding, adhesion, migration, and survival assays; (4) characterize the effects of cytokines and GPCR agonists on integrin-ligand interactions; and (5) prepare monoclonal antibodies to differentially spliced forms of VCAM and FN and determine distribution in normal and asthmatic lung.

（申请人摘要）嗜酸性粒细胞（EOS）优先积聚在 哮喘患者的气道并导致气道高反应性 和气流阻塞。选择性招募 EOS 的机制 哮喘可能包括： (a) EOS 循环的启动； (b) 地方上调 IL-4 和 IL-13 Th-2 细胞因子对血管细胞粘附分子 1 (VCAM) 的影响； (c) 已启动的循环 EOS 在表达 VCAM 的肺上滚动和停滞 内皮细胞； (d) 被抑制的 EOS 迁移到组织中以响应 G蛋白偶联受体（GPCR）的趋化因子或其他激动剂； （五） 尚未定义的趋化性、趋化性和趋化性事件，其中 EOS 与支气管壁中的 VCAM 和纤连蛋白 (FN) 相互作用； （六） EOS 移动到气道腔内； (g) EOS 的延长生存期 由 GM-CSF 驱动的气道壁和管腔。 EOS表达2个整合素 与 VCAM 和 FN、alpha4beta1 和 alpha4beta7 相互作用，还有第三个， alphaDbeta2，与 VCAM 相互作用，但不与 FN 相互作用。 VCAM 和 FN 各自存在为 几种不同的剪接形式。我们假设拼接 变异改变了整合素的 VCAM 和 FN 的特异性和效价 EOS 以及 EOS 对整合素连接的反应。我们的目标是 双重。首先，我们将确定 alpha4beta1 之间的相互作用， 具有 VCAM 和 FN 差异剪接形式的 alpha4beta7 和 alphaDbeta2 调节 EOS 的粘附、迁移和活力。其次，我们将确定 正常人和哮喘患者中各种形式的 VCAM 和 FN 的分布 航空公司。为了实现这些目标，我们将（1）表达差异剪接 EOS 在血液运输过程中可能遇到的 VCAM 和 FN 形式 至呼吸道； (2) 制备复制表达模式的细胞系 血液和气道 EOS 上的整合素，并作为 EOS 的模型 哮喘发作前后的循环和肺部； (3) 表征血液 EOS、气道 EOS 和模型细胞的能力 与 VCAM 和 FN 的剪接形式相互作用，进行结合、粘附、迁移和 生存分析； (4)表征细胞因子和GPCR激动剂的作用 关于整合素-配体相互作用； (5) 制备单克隆抗体 VCAM 和 FN 的差异剪接形式并确定分布 正常肺和哮喘肺。