Astrocytic LRP-1 Modulates Blood-Brain Barrier Function

目标： 这一应用的主要目标是研究低密度 脂蛋白受体相关蛋白1对血脑屏障通透性的调节作用 在生理条件下和缺血性中风后。 方法 在目标一中，我们将检验假设，在非缺血条件下，星形细胞LRP1 通过以下方式保持基底膜-星形胶质细胞(BM-A)界面的完整性 促进整合素在血管周围星形细胞末梢膜上的募集 足突及其与基底膜(BM)中的配体的结合。在AIM II中 我们认为，在缺血条件下，当细胞分裂时，这一功能丧失 血管周围星形胶质细胞LRP1胞外区激活细胞信号转导 增加血脑屏障(BBB)通透性的途径。在AIM III中，我们 将在缺血性卒中动物模型中研究是否抑制LRP1的裂解 从血管周围星形胶质细胞中提取的受体相关蛋白(RAP)可防止 内源性tPA和/或rtPA对血脑屏障通透性的不利影响。 研究计划 在这项应用的第一个目的中，我们将使用星形胶质细胞培养和细胞黏附 化验。在第二个目标中，我们将使用星形细胞培养，一个血液的体外模型- 脑屏障、实时聚合酶链式反应、共聚焦显微镜和免疫共沉淀分析。在……里面 第三个目标是我们将使用我们设计的纳米载体来选择性地传递其 脑缺血动物模型和缺血组织中血脑屏障的含量。

Objective: The main goal of this application is to study the mechanism whereby the low density lipoprotein receptor-related protein 1 (LRP1) modulates the permeability of the BBB under physiological conditions and after an ischemic stroke. Methods In Aim I we will test the hypothesis that under non-ischemic conditions astrocytic LRP1 preserves the integrity of the basement membrane-astrocyte (BM-A) interface by promoting the recruitment of integrins to the membrane of perivascular astrocytic end- feet processes and their binding to its ligands in the basement membrane (BM). In Aim II we propose that this function is lost under ischemic conditions when the cleavage of the extracellular domain of LRP1 from perivascular astrocytes activates a cell-signaling pathway that increases the permeability of the blood-brain barrier (BBB). In Aim III we will study in an animal model of ischemic stroke whether inhibition of LRP1 cleavage from perivascular astrocytes with the receptor-associated protein (RAP) prevents the harmful effects of endogenous tPA and/or rtPA on the permeability of the BBB. Research Plan In the first Aim of this application we will use astrocytic cell cultures and a cell adhesion assay. In the second Aim we will use astrocytic cultures, an in vitro model of the blood- brain barrier, real-time PCR, confocal microscopy and co-immunoprecipitation assays. In the third Aim we will use a nanocarrier that we engineered to selectively deliver its content to the BBB in the ischemic tissue and an animal model of cerebral ischemia.