Alternative Mechanisms of Monocyte Transendothelial Migration in Inflammation

炎症中单核细胞跨内皮迁移的替代机制

基本信息

批准号：
10312793
负责人：
Margarette Helen Clevenger
金额：
$ 4.21万
依托单位：
NORTHWESTERN UNIVERSITY AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-12-01 至 2024-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10312793
关键词：
Academia Acute Address Affect Air Anti-Inflammatory Agents Area Atherosclerosis Biological Assay Blood Circulation Blood Vessels CD31 Antigens Cell Adhesion Molecules Cells Chronic Confocal Microscopy Data Disease Endothelial Cells Event Flow Cytometry Gene Expression Profile Goals In Vitro Infection Inflammation Inflammatory Inflammatory Response Kinesin Knock-out Lateral Learning Left Leukocyte Adhesion Molecules Leukocytes Light Lymphocyte Mediating Membrane Membrane Protein Traffic Methods Microtubules Migration Assay Modeling Molecular Movement Mus Myocardial Infarction Pathologic Pathology Pathway interactions Phase Phenotype Population Process Property Receptor Signaling Recycling Refractory Reperfusion Injury Research Research Personnel Residual state Resistance Role Signal Pathway Signal Transduction Site Stimulus Stroke Structure Surface Therapeutic Time Tissues Ursidae Family Vasculitis body system career cell motility cell type chronic inflammatory disease clinical application combat comorbidity experience fighting in vitro Model in vivo innovation intravital microscopy migration monocyte mouse model neutrophil pathogen recruit response screening tissue repair trafficking transcriptome sequencing wound healing

项目摘要

Project Summary Inflammation serves a protective role in the body to fight infection and mediate wound healing; however, the inflammatory response can become deleterious if left uncontrolled or unresolved. Most pathology, including atherosclerosis, vasculitis, and ischemia/reperfusion injury—which can exacerbate potential comorbidities such as myocardial infarcts and stroke—is due to dysfunctional inflammation. Targeting inflammation could thus provide the means to combat inflammatory disease. This objective can be realized by targeting a common process that underlies all inflammation: the directed movement of white blood cells (WBCs) from circulation into affected tissue. In this process, transendothelial migration (TEM), WBCs migrate between lateral borders of endothelial cells (ECs) lining blood vessels to enter sites of inflammation. TEM is a critical step in the inflammatory response as it is the ultimate step preceding WBC access to inflamed tissue. Successful blocking of TEM would preclude tissue damage in an inflammatory context and is thus a therapeutic goal. TEM is mediated by interactions between surface adhesion molecules on the WBC and ECs, resulting in signaling within ECs that traffics membrane from the EC lateral border recycling compartment (LBRC), a perivascular vesiculotubular structure, to the site of TEM. This provides additional surface area required for WBC migration between adjacent ECs. Trafficking of LBRC is the final common pathway for TEM regardless of WBC type or inflammatory stimulus. Blocking critical adhesion molecules or downstream EC signaling pathways blocks TEM of WBC by 80-90% in vitro and in vivo. However, residual transmigration rate remains 10-20%, raising the question as to whether specific subpopulation(s) of WBC are resistant to TEM blockade and whether non-blocked WBCs use alternative signaling pathways to recruit the LBRC to transmigrate. AIM I will phenotypically characterize monocytes that overcome TEM blockade to determine if they represent a distinct monocyte subset. I will interrogate the mechanism by which these cells transmigrate in an in vitro TEM model and in murine models of inflammation. This will allow for the identification of surface receptors/signaling pathways that can be targeted to block the exit of all circulating monocytes from the vasculature in situations in which blocking 100% of inflammation is critical. AIM II will interrogate mechanisms that allow these monocytes to use alternative transmigration pathways. I will utilize a guided in vitro screening approach and in vivo real time intravital confocal microscopy to validate my in vitro results by inspecting mechanisms functioning at the TEM step directly. The project will shed light on alternative TEM pathways that may be important under some pathologic conditions and alert us to ways in which the body may compensate for the chronic blockade of traditional TEM pathways.

项目概要炎症在身体中发挥保护作用，抵抗感染并促进伤口愈合；然而，如果不加以控制或解决，炎症反应可能会变得有害。包括动脉粥样硬化、血管炎和缺血/再灌注损伤——这可能会恶化潜在的风险心肌梗塞和中风等合并症是由于炎症功能失调造成的。因此，炎症可以提供对抗炎症性疾病的手段，这一目标可以通过以下方式实现。针对所有炎症的共同过程：白细胞的定向运动（白细胞）从循环进入受影响的组织在此过程中，白细胞通过内皮迁移（TEM）迁移。内皮细胞 (EC) 的侧缘之间的血管内皮细胞进入炎症部位。炎症反应中的关键步骤，因为它是白细胞进入发炎组织之前的最终步骤。成功阻断 TEM 将防止炎症环境下的组织损伤，因此是一种治疗目标。 TEM 由 WBC 和 EC 上的表面粘附分子之间的相互作用介导，从而产生在 EC 内从 EC 侧边界回收室 (LBRC) 传输膜的信号中，血管周围的囊管结构，到 TEM 的位置，这提供了所需的额外表面积。无论何种情况，LBRC 之间的 WBC 迁移都是 TEM 的最终共同途径。 WBC 类型或炎症刺激物阻断关键粘附分子或下游 EC 信号传导。在体外和体内，该途径可将 WBC 的 TEM 阻断 80-90%，但残留迁移率仍然存在。 10-20%，提出了具体的 WBC 亚群是否对 TEM 封锁具有抵抗力的问题以及未阻断的白细胞是否使用替代信号通路来募集 LBRC 进行迁移。 AIM I 将对克服 TEM 封锁的单核细胞进行表型表征，以确定它们是否代表一个独特的单核细胞亚群，我将探讨这些细胞在一个细胞中迁移的机制。体外 TEM 模型和小鼠炎症模型，这将允许识别表面。受体/信号通路可以靶向阻止所有循环单核细胞从在阻断 100% 炎症至关重要的情况下，AIM II 将询问机制。允许这些单核细胞使用替代的迁移途径，我将利用引导体外筛选。方法和体内实时活体共聚焦显微镜通过检查来验证我的体外结果该项目将阐明直接在 TEM 步骤中发挥作用的替代 TEM 途径。在某些病理条件下可能很重要，并提醒我们身体可以补偿的方式传统 TEM 路径的长期封锁。