Regulation of cellular functions by the plasminogen receptor, Plg-RKT

项目摘要/摘要 纤溶酶原激活系统在广泛的范围内调节炎症反应 纸巾。炎症对于维持正常的组织内环境平衡是必不可少的，而炎症的失调会导致 广泛的病理影响，包括纤维化、疤痕形成、伤口异常愈合、感染、败血症、 自身免疫性疾病和哮喘。知识中的一个关键差距是理解 纤溶酶原与细胞沟通，调节炎症反应。PLG-RKT是一种新型的整体膜 通过暴露在细胞表面的C端赖氨酸与纤溶酶原结合的蛋白质，并促进细胞表面 纤溶酶原激活。我们实验室的长期目标是了解PLG-RKT 调节生理和病理过程。这一建议是基于新的数据显示PLG-RKT 促进CCL2的表达，CCL2是促炎反应的关键介质，也是一种潜在的干预手段 用于治疗含有炎症成分的疾病的穴位。更多的结果支持挑衅性的 出现了调控CCL2表达的概念，而不是细胞表面对细胞外基质的蛋白分解 是纤溶酶原/PLG-RKT控制单个核细胞募集的主要机制 体内炎症反应。需要解决的中心假设是纤溶酶(原)/PLG-RKT- 依赖性促进CCL2表达是促进纤溶酶原/PLG-RKT-1的主要机制 依赖单个核细胞在炎症反应中的募集。这一假说将在小鼠身上进行验证 胸膜炎和腹膜炎模型。我们将研究PLG-RKT在炎症反应中的作用。 哮喘因为在辅助性T细胞2型(Th2)免疫相关疾病中，如哮喘，CCL2高表达 在动物模型中的水平及其中和可以改善疾病。这项建议的目标是 研究PLG-RKT在体内CCL2合成中的作用及其对PLG-RKT依赖的影响 并探讨PLG-RKT在哮喘发病机制中的作用。我们的特定 目的：(1)研究PLG-RKT在体内CCL2合成中的作用及其对PLG-RKT依赖性的影响 (2)探讨PLG-RKT在哮喘发病中的作用。我们将使用 PLG-RKT缺陷小鼠和高表达PLG-RKT小鼠检测纤溶酶原/PLG-RKT依赖 CCL2在体内的上调依赖于PAR-1。我们将使用单细胞RNA测序来鉴定细胞类型 负责依赖PLG-RKT刺激CCL2的表达，我们将确定外源性 添加CCL2可修复PLG-RKT-/-小鼠巨噬细胞募集功能受损。我们将调查 PLG-RKT在卵白蛋白诱导哮喘炎症中的作用及PLG-RKT是否对呼吸道有调节作用 高反应性(AHR)。我们期望我们的具体目标的实现将使PLG-RKT成为 通过调节关键的趋化物质CCL2的表达来调节炎症反应的关键调节因子 并提供了关于单个核细胞招募如何受到监管的基本见解。

Project Summary/Abstract The plasminogen activation system extensively regulates the inflammatory response in a broad range of tissues. Inflammation is essential for maintenance of normal tissue homeostasis and its dysregulation has a broad pathologic impact, including development of fibrosis, scarring, aberrant wound healing, infection, sepsis, autoimmune disease and asthma. A critical gap in knowledge is understanding the mechanisms by which plasminogen communicates with cells to regulate inflammatory responses. Plg-RKT is a novel integral membrane protein that binds plasminogen via a C-terminal lysine exposed on the cell surface and promotes cell surface plasminogen activation. The long-term goal of our laboratory is to understand mechanisms by which Plg-RKT regulates physiologic and pathologic processes. This proposal is based on new data showing that Plg-RKT promotes expression of CCL2, a key mediator of the pro-inflammatory response, and a potential intervention point for the treatment of diseases with an inflammatory component. Additional results support the provocative concept that regulation of CCL2 expression, rather than cell surface proteolysis of extracellular matrix, appears to be the primary mechanism for plasminogen/Plg-RKT control of mononuclear cell recruitment in the inflammatory response in vivo. The central hypothesis to be addressed is that plasmin(ogen)/Plg-RKT- dependent promotion of CCL2 expression is the primary mechanism for promotion of plasmin(ogen)/Plg-RKT- dependent mononuclear cell recruitment in the inflammatory response. The hypothesis will be tested in murine models of pleurisy and peritonitis. And we will investigate the role of Plg-RKT in the inflammatory response in asthma because in T helper type 2 (Th2) immune-related diseases, such as asthma, CCL2 is expressed at high levels and its neutralization in animal models ameliorates disease. The objectives of this proposal are to investigate the role of Plg-RKT in CCL2 synthesis in vivo and assess its impact on Plg-RKT-dependent mononuclear cell recruitment and to examine the role of Plg-RKT in the pathogenesis of asthma. Our specific aims are (1) to investigate the role of Plg-RKT in CCL2 synthesis in vivo and its impact on Plg-RKT-dependent mononuclear cell recruitment and (2) to examine the role of Plg-RKT in the pathogenesis of asthma. We will use Plg-RKT deficient mice and mice over-expressing Plg-RKT to test whether plasmino(ogen)/Plg-RKT-dependent CCL2 up-regulation in vivo is PAR-1- dependent. We will use single cell RNA sequencing to identify cell types responsible for Plg-RKT-dependent stimulation of CCL2 expression and we will determine whether exogenously added CCL2 can rescue the impairment in macrophage recruitment in Plg-RKT-/- mice. We will investigate the role of Plg-RKT in inflammation in ovalbumin-induced asthma and determine whether Plg-RKT regulates airway hyper-responsiveness (AHR). We expect that accomplishment of our specific aims will establish Plg-RKT as a pivotal regulator of the inflammatory response via regulation of expression of the key chemoattractant, CCL2, and provide fundamental insights into how mononuclear cell recruitment is regulated.