Role of intravascular ERO1@ in acute lung injury

项目摘要 急性肺损伤（ALI）是一种危及生命的疾病，在美国每年影响> 200，000名患者。 与肺炎、败血症和创伤相关，导致肺功能不全，最终导致多系统 器官衰竭由于活化的中性粒细胞向肺微血管的过度募集是肺栓塞的主要原因， ALI，更好地了解介导嗜酸性粒细胞-内皮细胞相互作用的机制将提供 深入了解开发治疗ALI的有效疗法。我们以前证明了血管内 蛋白质二硫键异构酶（PDI）增强中性粒细胞和血小板表面受体的配体结合活性 并在血管炎症期间导致血管内细胞-细胞相互作用。为了阐明细胞外PDI 活动受到调节，以及调节机制是否有助于ALI的病理，我们发现， 内质网氧化还原蛋白1α（ERO 1 α，ER中PDI的关键氧化酶）促进中性粒细胞 血管炎症期间的募集。在这个提议中，我们将检验血管内ERO 1 α 通过修饰二硫键，诱导 中性粒细胞募集到急性肺部炎症部位。在目标1中，我们将确定 ERO 1 α调节嗜酸性粒细胞-内皮细胞相互作用。在目标2中，我们将利用肺部实时成像技术， 探讨血管内ERO 1 α在急性肺损伤中的病理作用。在目标3中，使用急性胰腺炎患者的血液， 呼吸窘迫综合征（ARDS），我们将确定ERO 1 α对疾病进展的贡献 和严重程度。这些研究将采用生物化学，细胞生物学，遗传学和共聚焦显微镜。 活体成像方法。由于对细胞外巯基修饰机制知之甚少， 研究将确定一种促进ALI/ARDS发病的重要但尚未探索的机制。

Project Summary Acute lung injury (ALI) is a life-threatening condition, which affects > 200,000 patients annually in the U.S. It is associated with pneumonia, sepsis, and trauma, leading to pulmonary insufficiency and eventually multisystem organ failure. Since excessive recruitment of activated neutrophils to lung microvessels is a primary cause of ALI, a better understanding of the mechanism mediating neutrophil-endothelial cell interactions will provide insight into developing an effective therapeutic for treating ALI. We previously demonstrated that intravascular protein disulfide isomerase (PDI) enhances the ligand-binding activity of neutrophil and platelet surface receptors and leads to intravascular cell-cell interactions during vascular inflammation. To elucidate how extracellular PDI activity is regulated and whether the regulatory mechanism contributes to the pathology of ALI, we have found that endoplasmic reticulum oxidoreductin 1α (ERO1α, a key oxidase of PDI in the ER) promotes neutrophil recruitment during vascular inflammation. In this proposal, we will test the hypothesis that intravascular ERO1α enhances the ligand-binding function of neutrophil adhesion receptors by modifying disulfide bonds, inducing neutrophil recruitment to sites of acute lung inflammation. In Aim 1, we will determine the mechanism by which ERO1α regulates neutrophil-endothelial cell interactions. In Aim 2, we will utilize lung live imaging techniques to investigate the pathological role of intravascular ERO1α in ALI. In Aim 3, using the blood of patients with acute respiratory distress syndrome (ARDS), we will determine the contribution of ERO1α to the disease progression and severity in patients with ARDS. These studies will employ biochemical, cell biological, genetic, and confocal intravital imaging approaches. Since little is known about extracellular thiol-modifying machinery, the proposed studies will identify an essential, yet unexplored, mechanism that promotes the pathogenesis of ALI/ARDS.