CD 8 T Cell Mediated Disruption of Blood Brain Tight Junction

描述（由申请人提供）：血脑屏障破坏（BBB）是许多严重神经系统疾病的常见病理特征。尽管这些与中枢神经系统血管通透性相关的神经系统疾病带来了巨大的发病率和死亡率负担，但炎症细胞如何促进血脑屏障破坏的潜在分子机制仍然知之甚少。我们已经开发了一种新的小鼠中枢神经系统血管通透性模型，该模型提供了一种易于处理的方法来定义使用Theiler病毒感染破坏血脑屏障的体内特异性炎症介质。这种小鼠血脑屏障破坏模型是由CNS浸润CD8 T细胞的肽特异性刺激引发的，而不是由TNF-a、IFN-？， LT¿R和IL- 1。然而，穿孔素对中枢神经系统血管通透性和血脑屏障紧密连接的保存都是至关重要的。值得注意的是，尽管具有相同的CD8+ T细胞反应和CTL活性，mhc相同的C57BL/6和129 svm小鼠对PIFS的易感性存在显着差异。本提案的目的是验证我们的基本假设，即CD8 T细胞利用穿孔素启动脑内皮细胞血脑屏障紧密连接的破坏。C57BL/6和129 SvIm小鼠背景上的特异性修饰基因也对这一过程的发生至关重要。我们将使用该模型确定：1.)血脑屏障破坏所需穿孔素的细胞来源，2.)造血细胞在促进血脑屏障破坏中的作用，以及3.)控制血脑屏障破坏的遗传因素的染色体位置。我们将使用传统的遗传分析、蛋白质生物化学、成像、细胞免疫学分析、分子生物学和逆转录病毒表达来确定介导血脑屏障破坏的炎症因子。鉴定导致致命中枢神经系统血管通透性的强大因素将确定治疗性血脑屏障修饰的靶点。以血脑屏障破坏为特征的疾病包括中风、病毒性出血热、脑性疟疾、艾滋病毒痴呆、多发性硬化症（MS）和休克。加深对血脑屏障通透性的了解也有助于化疗。公共卫生相关性：炎症介导的血脑屏障（BBB）破坏是许多神经系统疾病的一个相对常见的特征，但人们对其知之甚少。我们开发了一种新的小鼠中枢神经系统血管通透性模型，该模型可用于定义体内导致血脑屏障破坏的特定细胞相互作用和炎症介质。确定这些因素是治疗血脑屏障通透性的第一步。

DESCRIPTION (provided by applicant): Disruption of the Blood Brain Barrier (BBB) is common pathologic feature of numerous serious neurological diseases. Despite the enormous burden of morbidity and mortality due to these neurological diseases associated with CNS vascular permeability, the underlying molecular mechanisms of how inflammatory cells promote BBB disruption remain poorly understood. We have developed a novel murine model of CNS vascular permeability that provides a tractable approach to defining specific inflammatory mediators that disrupt the BBB in vivo using Theiler's virus infection. This murine model of BBB disruption is initiated by peptide-specific stimulation of CNS infiltrating CD8 T cells and is not mediated by TNF-a, IFN-?, LT¿R and IL- 1. However, perforin is critical for both CNS vascular permeability and preservation of BBB tight junctions. Notably, MHC-identical C57BL/6 and 129 Svlm mice differ dramatically in susceptibility to PIFS, despite having identical CD8+ T cell responses and CTL activity. The goal of this proposal is to test our underlying hypothesis that CD8 T cells utilize perforin to initiate the disruption of cerebral endothelial cell BBB tight junctions. Specific modifier genes on the C57BL/6 and 129 SvIm mouse background are also critical for this process to occur. We will determine using this model: 1.) the cellular source of perforin necessary for BBB disruption, 2.) the role of hematopoetic cells in promoting disruption of the BBB, and 3.) the chromosome location of genetic factors that govern BBB disruption. We will use conventional genetic analysis, protein biochemistry, imaging, cellular immunology assays, molecular biology and retrovirus expression to determine the inflammatory factors that mediate disruption of the BBB. Identification of powerful factors that contribute to fatal CNS vascular permeability would define targets for therapeutic modification of the BBB. Such diseases characterized by disruption of the BBB including stroke, viral hemorrhagic fevers, cerebral malaria, HIV dementia, multiple sclerosis (MS), and shock. Increased understanding of BBB permeability could also benefit chemotherapy. PUBLIC HEALTH RELEVANCE: Inflammation mediated blood brain barrier (BBB) disruption is a poorly understood, yet relatively common feature of numerous neurologic diseases. We have developed a novel murine model of CNS vascular permeability that can be utilized to define specific cellular interactions and inflammatory mediators that result in disruption of the BBB in vivo. Defining such factors is the first step towards novel therapeutic modification of BBB permeability.