Protein disulfide isomerase in neutrophil recruitment and vascular inflammation

中性粒细胞募集和血管炎症中的蛋白质二硫键异构酶

• 批准号: 8160774
• 负责人: Jaehyung Cho
• 金额: $ 39.75万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8160774
• 关键词: Acute; Address; Adhesions; Antibodies; Binding; Blood Platelets; Blood Vessels; Cell Surface Proteins; Cell Surface Receptors; Cell physiology; Cell surface; Cells; Data; Development; Disulfides; Endothelial Cells; Endothelium; Hematopoietic; Immune response; In Vitro; Inflammation; Inflammatory; Injury; Integrins; Intercellular adhesion molecule 1; Isomerase; Knockout Mice; Lead; Life; Ligands; Macrophage-1 Antigen; Mediating; Membrane Proteins; Microscopy; Modeling; Molecular; Molecular Conformation; Morbidity - disease rate; Mus; Neutrophil Activation; Neutrophil Infiltration; Oxidation-Reduction; Play; Process; Protein Disulfide Isomerase; Reactive Oxygen Species; Recombinant Proteins; Recruitment Activity; Regulation; Relative (related person); Role; Selectins; Site; Specificity; Sulfhydryl Compounds; Surface; Testing; Time; Tissues; Vascular Endothelial Cell; base; cremaster muscle; disulfide bond; in vivo; inhibitor/antagonist; intravital fluorescence microscopy; intravital microscopy; mortality; neutrophil; novel; novel therapeutics; prevent; receptor; small hairpin RNA; vascular inflammation; venule

DESCRIPTION (provided by applicant): Neutrophils are essential for the innate immune response during vascular inflammation and injury. Neutrophil recruitment into the site of vascular injury is a multi-step process consisting of neutrophil rolling, firm adhesion, and transmigration. Interaction of selectins with their ligands mediates neutrophil rolling over the inflamed endothelium and further regulates integrin function. Subsequently, activated LFA-1 and Mac-1 play critical roles in neutrophil adhesion to and transmigration across the endothelium. However, the molecular mechanism by which the integrins are activated during neutrophil recruitment remains unclear. It has been proposed that redox-sensitive thiol-disulfide exchange in integrins may be important for their activation. Protein disulfide isomerase (PDI), a cell surface localized thiol isomerase, plays an important role in thiol exchange in b3 integrins, thereby regulating b3 integrin-mediated platelet and endothelial cell function. It is our hypothesis that neutrophil surface PDI regulates b2 integrin function by facilitating redox-sensitive thiol exchange, shifting b2 integrin to its active conformation required for b2 integrin-mediated neutrophil recruitment during inflammation. Based on our preliminary data which strongly support the hypothesis, in Aim 1, we will define the role of cell surface PDI in the interaction of b2 integrin with its counter-receptor, ICAM-1 and in b2 integrin-mediated neutrophil adhesion and transmigration. In Aim 2, we will identify the molecular mechanisms by which PDI interacts with b2 integrins to regulate their function. In Aim 3, we will investigate the pathophysiological role of cell surface PDI in b2 integrin-mediated neutrophil adhesion and transmigration under inflammatory conditions using real-time fluorescence intravital microscopy in vivo. A better understanding of how surface PDI regulates b2 integrin-mediated neutrophil recruitment into the site of inflammation may lead to the development of novel therapeutics to prevent and treat inflammation and tissue injury. PUBLIC HEALTH RELEVANCE: Acute inflammation leads to high mortality and morbidity in the U.S. The proposed studies will help determine how circulating neutrophils recruit into the site of inflammation. Integrins (cell surface receptors) are necessary for neutrophil recruitment during inflammation. Therefore, molecules such as PDI which can regulate integrin function could be a novel target to prevent and treat inflammation.

描述（由申请方提供）：中性粒细胞对于血管炎症和损伤期间的先天免疫应答至关重要。中性粒细胞向血管损伤部位的募集是一个多步骤的过程，包括中性粒细胞滚动、牢固粘附和迁移。选择素与其配体的相互作用介导中性粒细胞在发炎的内皮上滚动，并进一步调节整合素功能。随后，激活的LFA-1和Mac-1在中性粒细胞粘附和跨内皮迁移中起关键作用。然而，在中性粒细胞募集过程中整合素被激活的分子机制仍不清楚。已经提出，整合素中的氧化还原敏感的巯基-二硫键交换可能对它们的活化很重要。蛋白质二硫键异构酶（PDI）是一种位于细胞表面的巯基异构酶，在b3整合素的巯基交换中起重要作用，从而调节b3整合素介导的血小板和内皮细胞功能。我们的假设是，中性粒细胞表面PDI通过促进氧化还原敏感性巯基交换，将b2整联蛋白转变为炎症期间b2整联蛋白介导的中性粒细胞募集所需的活性构象来调节b2整联蛋白功能。基于我们的初步数据，这有力地支持了这一假设，在目的1中，我们将确定的作用，细胞表面的PDI的b2整合素与其反受体，ICAM-1的相互作用，并在b2整合素介导的中性粒细胞粘附和迁移。在目标2中，我们将确定PDI与b2整合素相互作用以调节其功能的分子机制。在目标3中，我们将使用实时荧光活体显微镜在体内研究在炎症条件下细胞表面PDI在b2整合素介导的中性粒细胞粘附和迁移中的病理生理作用。更好地了解表面PDI如何调节b2整合素介导的中性粒细胞募集到炎症部位可能会导致开发新的治疗方法来预防和治疗炎症和组织损伤。 公共卫生相关性：在美国，急性炎症导致高死亡率和发病率。拟议的研究将有助于确定循环中性粒细胞如何招募到炎症部位。整合素（细胞表面受体）是炎症过程中中性粒细胞募集所必需的。因此，能够调节整合素功能的分子如PDI可能是预防和治疗炎症的新靶点。