Pathological Consequences of the Plasminogen System

描述（由申请人提供）：本提案的长期目标是利用体内模型在生理和病理生理过程中鉴定纤维蛋白溶解系统及其抑制剂的功能并确定其机制。通过纤溶酶催化纤维蛋白降解的能力，纤溶系统在止血中的作用已在体外和体内模型中得到广泛研究。纤维蛋白溶解系统的成分在许多细胞表面上的受体的鉴定暗示纤溶酶在细胞迁移事件中发挥作用。具有纤维蛋白溶解系统的编码组分的基因的单个和多个缺陷的小鼠的可用性已经导致直接分析这些蛋白质在许多生理和病理事件中的作用。先前的研究已经证明了这些蛋白质的缺乏在动脉粥样硬化、肺纤维化、皮肤伤口愈合、肿瘤生长和血管生成中的显著影响。由于PA 1 -1缺陷对血管损伤/修复、肿瘤生长、血管生成和伤口愈合的影响，本申请中描述的研究将集中于以下研究： 1.）由于PA 1 -1缺陷减少血管生成，因此将利用PA 1 -1-/-内皮细胞研究对内皮细胞增殖、迁移、发芽、定向迁移、凋亡和血管生成调节分子表达的影响。 2.）的情况。通过产生表达突变的PA 1 -1蛋白的小鼠并用具有与血管生成反应相关的表型的模型攻击这些小鼠，确定PA 1 -1对血管生成的作用是否通过细胞粘附的改变、纤溶酶原激活物功能的抑制或uPA介导的细胞信号传导介导。 3.）第三章利用目标1中描述的分析进一步表征目标2中描述的源自小鼠的内皮细胞的功能缺陷。

DESCRIPTION (provided by applicant): The long-term goal of this proposal is to identify functions and determine mechanisms of the fibrinolytic system, and its inhibitors, in physiological and pathophysiological processes utilizing in vivo models. The contribution of the fibrinolytic system in hemostasis, through the capacity of plasmin to catalyze degradation of fibrin, has been extensively studied in both in vitro and in vivo models. The identification of receptors for components of the fibrinolytic system on a number of cell surfaces implicates plasmin as playing a role in cell migratory events. The availability of mice with single and multiple deficiencies of genes encoding components of the fibrinolytic system have resulted in direct analyses of the role of these proteins in a number of physiological and pathological events. Previous studies have demonstrated dramatic effects of deficiencies of these proteins in atherosclerosis, pulmonary fibrosis, skin wound healing, tumor growth, and angiogenesis. Due to the impact of a PAl-1 deficiency on vascular injury/repair, tumor growth, angiogenesis, and wound healing, studies described in this application will focus on the following studies: 1.) Since a PAl-1 deficiency diminishes angiogenesis, the effects on endothelial cell proliferation, migration, sprouting, directed migration, apoptosis, and expression of angiogenic regulatory molecules will be studied utilizing PAl-1-/- endothelial cells. 2.) Determine whether the PAl-1 effects on angiogenesis are mediated through alterations in cell adhesion, inhibition of plasminogen activator function, or uPA-mediated cell signaling by generating mice expressing mutated PAl-1 proteins and challenging these mice with models with phenotypes associated with an angiogenic response. 3.) Further characterize functional deficits of endothelial cells derived from mice described in Aim 2 utilizing analyses described in Aim 1.