CD 8 T Cell Mediated Disruption of Blood Brain Tight Junction

描述(申请人提供)：血脑屏障障碍(BBB)是许多严重神经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造成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。我们开发了一种新的中枢神经系统血管通透性的小鼠模型，该模型提供了一种容易处理的方法来确定特定的炎性介质，这些介质利用泰勒氏病毒感染在体内破坏血脑屏障。这种小鼠血脑屏障破坏模型是由多肽特异性刺激中枢神经系统渗入的CD8 T细胞启动的，不受肿瘤坏死因子-α、干扰素-β、LT？R和IL-1的介导。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护都是至关重要的。值得注意的是，MHC相合的C57BL/6和129 Svlm小鼠对PIF的敏感性显著不同，尽管它们具有相同的CD8 T细胞反应和CTL活性。这项提议的目的是测试我们的基本假设，即CD8T细胞利用穿孔素启动脑内皮细胞BBB紧密连接的破坏。C57BL/6和129SvIm小鼠背景上的特定修饰基因也是这一过程发生的关键。我们将使用此模型确定：1.)血脑屏障破坏所必需的穿孔素的细胞来源，2.)3.造血细胞在促进血脑屏障破坏中的作用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、蛋白质生化、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。确定导致致命性中枢神经系统血管通透性的强大因素将为血脑屏障的治疗修饰确定靶点。这些疾病的特征是血脑屏障的破坏，包括中风、病毒性出血热、脑型疟疾、艾滋病毒痴呆、多发性硬化症(MS)和休克。增加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中一种知之甚少但相对常见的特征。我们开发了一种新的中枢神经系统血管通透性的小鼠模型，可以用来确定导致体内血脑屏障破坏的特定细胞相互作用和炎症介质。确定这些因素是朝着改善血脑屏障通透性的新疗法迈出的第一步。

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.