Adhesion and Migration in Inflammation

描述（由申请人提供）： 在炎症过程中，白细胞从循环中募集到组织中。为了离开血流，白细胞必须粘附并迁移穿过血管的内皮衬里。该建议旨在了解这一过程中的一系列复杂的粘附和迁移事件。第一个项目将研究内皮细胞对粘附的白细胞做出反应时产生的信号。我们将研究Rho GTP酶在白细胞诱导的内皮杯组装中的作用。将研究白细胞如何操纵内皮细胞-细胞连接的完整性以允许白细胞通过。Rapt，RhoA和Rac 1 GTP酶的作用将在此过程中进行研究。此外，内皮连接蛋白酪氨酸磷酸化的作用将在白细胞跨内皮迁移过程中确定。第二个项目将侧重于在血管损伤的情况下，白细胞-血小板相互作用，其中内皮细胞丢失，血小板提供受损血管的细胞层衬里。Rap 1亚型和酪氨酸激酶Pyk 2的作用将在白细胞与血小板相互作用中进行研究。这项工作将扩展到动脉损伤和炎症的体内小鼠模型。 丝状伪足是细长的肌动蛋白为基础的突起，介导炎症过程中白细胞和内皮细胞之间的初始接触。第三个项目将研究肌球蛋白X在丝状伪足功能和内皮杯组装中的作用。所有项目都将利用成像和生物传感器核心，这将允许最先进的活细胞成像，特别强调通过荧光共振能量转移（FRET）对活性信号分子的可视化。该计划项目提案的长期目标是阐明炎症过程中的关键信号事件，这可能导致心血管疾病和其他炎症性疾病的新疗法的开发。

DESCRIPTION (provided by applicant): During inflammation leukocytes are recruited from the circulation into tissues. In order to leave the bloodstream leukocytes must adhere to and migrate across the endothelial lining of blood vessels. This proposal is aimed at understanding the complex series of adhesive and migratory events in this process. The first project will investigate the signals generated in endothelial cells as they respond to adhering leukocytes. We will investigate the roles of Rho GTPases in the assembly of leukocyte-induced endothelial cups. How leukocytes manipulate the integrity of endothelial cell-cell junctions to allow leukocyte passage will be studied. The roles of the Rapt, RhoA and Rac1 GTPases will be investigated in this process. Additionally, the role of tyrosine phosphorylation of endothelial junctional proteins will be determined during leukocyte transendothelial migration. The second project will focus on leukocyte-platelet interactions in the context of vascular injury where endothelial cells are lost and platelets provide the cellular layer lining damaged blood vessels. The roles of Rap1 isoforms and the tyrosine kinase Pyk2 will be studied in leukocytes interacting with platelets. The work will be extended to in vivo mouse models of arterial injury and inflammation. Filopodia are slender actin-based protrusions that mediate the initial contacts between leukocytes and endothelial cells during inflammation. The third project will investigate myosin X in filopodial function and endothelial cup assembly. All of the projects will take advantage of an imaging and biosensor core that will permit state of the art live cell imaging with special emphasis on the visualization of active signaling molecules by fluorescence resonance energy transfer (FRET). The long term goal of this program project proposal is to elucidate critical signaling events during inflammation that may lead to the development of novel therapies for cardiovascular disease and other inflammatory disorders.