Cell Movement Through a TH2-Conditioned Extracellular Matrix

我们的长期目标是了解嗜酸性粒细胞(EOS)如何在主航道上流动和相互作用，并做出贡献 与哮喘的进展有关。AM32整合素(CD11b/CD18)在获得的EOS上高度激活 节段性抗原攻击后的支气管肺泡灌洗，提示AM(32个功能变为 重要的是嗜酸性粒细胞渗入肺内并在肺内迁移。然而，人们对Amp2和Amp2的作用知之甚少。 与嗜酸性粒细胞在呼吸道中的黏附、迁移和活性有关的配体(S)。这样做的总体目标是 建议确定Amp2在调节EOS在大路上的行为中所起的作用。基于我们的 哮喘的EOS生物学和细胞外基质(ECM)的初步数据和当前的了解 目前的假说是Periostin，一种由辅助性T细胞2型驱动炎症的ECM蛋白 在哮喘的AIN/VAY中发现的细胞是EOS Amp2整合素的主要黏附配体，并且 Amp2-Periostin相互作用是EOS功能的重要决定因素。目标1是定义aMp2的角色， Periostin和转化生长因子-β诱导蛋白(TGFBI)，一种也在肺中发现的Periostin同源物，在黏附、迁移、 IL-3、IL-5、GM-CSF或其他激活剂激活的EOS的其他功能。目标2是 确定Amp2识别Periostin的构效关系，绘制Amp2结合图 站点(S)，并定义了当固定支撑物时和当可溶块时EOS的最小构造 黏附和迁移。维生素K依赖的γ-羧化和选择性剪接如何影响 Periostin的生物活性也将被确定。目标3是了解机制和 哮喘气道中Periostin显著升高的意义。Periostin分泌自 转化生长因子-β或其他因子刺激成纤维细胞和上皮细胞及其在细胞外基质和细胞外基质中的沉积 将对营业额进行分析。针对不同形式的Periostin和TGFBI的抗体将为 节段性抗原攻击后的支气管镜活检定位。实现这项提案的目标将 提供新的知识，更好地了解EOS的贩运和功能及其相互作用 在EOS和ECM之间的Th2驱动的炎症中，并将产生试剂和试剂，使 这种相互作用有待研究和调节。 Rele^Vance(请参阅说明)： 这项拟议的研究将确定结缔组织蛋白Periostin是如何上调的- 在哮喘中调节，与其细胞表面受体蛋白Amp2整合素(CD11b/CD18)相互作用于激活 EOS，支持EOS的附着和迁移。该项目将提供对 哮喘患者肺中嗜酸性粒细胞的运动和结缔组织的生物学。

Our long-term goal is to understand how eosinophils (EOS) traffic to and interact in the ainway and contribute to the progression of asthma. aM32 integrin (CD11b/CD18) is highly activated on EOS obtained by bronchoalveolar lavage after segmental antigen challenge, suggesting that aM(32 functions becomes important as EOS extravasate to and migrate in the lung. However, little is known about roles of aMp2 and relevant ligand(s) in adhesion, migration, and activities of EOS in the airway. The overall objective of this proposal is to determine the role of aMp2 in modulating behavior of EOS in the ainway. Based on our preliminary data and current understanding of EOS biology and the extracellular matrix (ECM) in asthma, the current hypothesis is that periostin, an ECM protein characteristic of inflammation driven by T helper type 2 cells and found in the asthmatic ain/vay, is a dominant adhesive ligand for EOS aMp2 integrin and that the aMp2-periostin interaction is an important determinant of EOS function. Aim 1 is to define roles of aMp2, periostin and TGF-P-induced protein (TGFBI), a periostin homolog also found in lung, in adhesion, migration, sun/ival, and other functions of EOS activated by IL-3, IL-5, GM-CSF, or other activators. Aim 2 is to determine the structure-function relationship ofthe recognition of periostin by aMP2, map the aMp2-binding site(s), and define minimal constructs that when immobilized support, and when soluble block, EOS adhesion and migration. How the vitamin K-dependent y-carboxylation and alternative splicing affect periostin's biological activities will also be determined. Aim 3 is to understand the mechanism and significance ofthe striking increase of periostin that is found in the asthmatic airway. Periostin secretion from fibroblasts and epithelial cells stimulated by TGF-p or other factors, as well as its deposition into ECM and turnover will be analyzed. Antibodies to the various forms of periostin and TGFBI will be developed for localization in bronchial biopsies after segmental antigen challenge. Achieving the goals of this proposal will provide novel knowledge and a better understanding of EOS trafficking and functions and the interplay between EOS and the ECM in Th2-driven inflammation, and will generate agents and reagents that will allow this interplay to be studied and modulated. RELE^VANCE (See instructions): The proposed research will determine how the connective tissue protein periostin, which is strongly up- regulated in asthma, interacts with its cell-surface receptor protein aMP2 integrin (CD11b/CD18) on activated EOS, and supports attachment and migration of EOS. The project will provide new insights into the movement of EOS in the asthmatic ainway and the biology of connective tissue in the diseased lung.