Mechanisms of blood-brain barrier disruption by an encephalitic virus

脑炎病毒破坏血脑屏障的机制

• 批准号: 8260848
• 负责人: Katherine R. Spindler
• 金额: $ 50.41万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8260848
• 关键词: Actins; Address; Adenoviruses; Astrocytes; Basic Science; Biological Assay; Biological Models; Blood - brain barrier anatomy; Brain; Capsid; Capsid Proteins; Cells; Central Nervous System Diseases; Cleaved cell; Cultured Cells; Cytoskeleton; DNA; DNA Sequence Rearrangement; DNA Viruses; Data; Development; Disease; Drug Delivery Systems; Encephalitis; Endothelial Cells; Family; Fiber; Genetic; Goals; Homeostasis; Human; Immune; Immune response; Immunology; In Situ; In Vitro; Infection; Infectious Agent; Infiltration; Inflammatory; Integrins; Intercellular Junctions; Knock-out; Knowledge; Lead; Leukocytes; Matrix Metalloproteinases; Microglia; Mission; Modeling; Molecular; Molecular and Cellular Biology; Morbidity - disease rate; Mus; Mutant Strains Mice; Natural Immunity; Neurobiology; Outcome; Pathogenesis; Pathway interactions; Pattern; Permeability; Physiological; Play; Proteins; Proteolysis; Public Health; Publishing; RNA Viruses; Research; Resistance; Retroviridae; Role; Signal Pathway; Signal Transduction; System; Testing; Therapeutic Intervention; Tight Junctions; Toxin; United States National Institutes of Health; Vascular Endothelial Cell; Viral; Viral Encephalitis; Viral Genes; Viral Proteins; Virion; Virus; Virus Diseases; Work; base; burden of illness; cell type; chemokine; cytokine; improved; in vivo; in vivo Model; inhibitor/antagonist; innovation; insight; knockout gene; member; mortality; mutant; particle; pathogen; prevent; protein expression; public health relevance; virus host interaction

DESCRIPTION (provided by applicant): Viral encephalitis is a potentially deadly sequela of viral infection for which there are few treatment options. It is frequently associated with blood-brain barrier (BBB) disruption, enabling the entry of virus, inflammatory cells, and deleterious molecules into the brain parenchyma. Members of at least eleven virus families cause encephalitis, including DNA viruses, retroviruses and RNA viruses, with significant morbidity and mortality. Little is known about the mechanisms by which viral infections disrupt the BBB, including the specific viral genes involved and how viruses manipulate host functions that contribute to this important protective barrier. The long-term goal of this research is to improve therapy for people with encephalitis by understanding how viral gene products interact with the host to cause the disease. The overall objective of this application is to determine how a natural mouse pathogen that causes encephalitis, mouse adenovirus type 1 (MAV-1), disrupts the BBB. The central hypothesis is that one or more viral factors induce altered expression and/or function of endothelial cell tight junction proteins, leading to disruption of the BBB. The rationale is that once the mechanism of MAV-1 disruption of the BBB is known, the system can be manipulated genetically and pharmacologically in mice, resulting in innovative approaches for the treatment of encephalitides in humans. The hypothesis will be tested with two specific aims: 1) Identify the primary virus-induced host response leading to altered tight junction protein expression during MAV-1 infection, and 2) Identify the innate signaling and viral components responsible for destruction of BBB integrity. Aim 1 is based on published and preliminary data that MAV-1 reduces tight junction protein expression in brain endothelial cells and increases matrix metalloproteinase (MMP) expression in brains, astrocytes and microglia. Established assays for BBB permeability, MMP activity, and transendothelial resistance will be used to test the hypothesis that MMPs play a role in the decrease in tight junction proteins during infection. Gene knockout-, inhibitor-treated-, and leukocyte-depleted mice will be used to extend these findings in vivo. In Aim 2, viral mutants and physically altered virus particles will be used in in vivo and in vitro infections to test the hypothesis that viral components serve as pathogen-associated molecular patterns that signal innate immunity. To identify which innate immune signaling pathway(s) MAV-1 triggers, leading to BBB disruption, an ordered approach using infection of mouse gene knockouts will be employed. The proposed research is innovative because it uses a comprehensive approach to study BBB disruption caused by a viral pathogen in its natural host, addressing both viral and host contributions to encephalitis. This research will be significant because it will be the first viral mechanism of BBB disruption characterized in vivo in a natural host, contributing an understanding of the action of specific viral gene products and mammalian innate immunity on BBB function. This powerful mouse/MAV-1 model can be manipulated to evaluate innovative approaches to the treatment of encephalitis. PUBLIC HEALTH RELEVANCE: The proposed research is relevant to public health because the identification of specific viral mechanisms leading to disruption of the blood-brain barrier will increase understanding of the pathogenesis of viral encephalitis. Blood-brain barrier disruption is also observed in non-viral disease of the central nervous system (CNS). In addition, a functional barrier is a significant block to effective drug delivery. This research is ultimately expected to facilitate development of pharmacological approaches to treat both viral encephalitis and other CNS disease. Thus it addresses the NIH mission to reduce the burdens of illness.

描述（由申请人提供）：病毒性脑炎是一种潜在的致命后遗症的病毒感染，有几个治疗方案。它通常与血脑屏障（BBB）破坏有关，使病毒，炎性细胞和有害分子进入脑实质。至少11个病毒家族的成员引起脑炎，包括DNA病毒、逆转录病毒和RNA病毒，具有显著的发病率和死亡率。关于病毒感染破坏BBB的机制知之甚少，包括涉及的特定病毒基因以及病毒如何操纵有助于这一重要保护屏障的宿主功能。这项研究的长期目标是通过了解病毒基因产物如何与宿主相互作用导致疾病来改善脑炎患者的治疗。本申请的总体目标是确定引起脑炎的天然小鼠病原体小鼠腺病毒1型（MAV-1）如何破坏BBB。中心假设是一种或多种病毒因子诱导内皮细胞紧密连接蛋白的表达和/或功能改变，导致BBB破坏。其基本原理是，一旦MAV-1破坏BBB的机制已知，该系统可以在小鼠中进行遗传操作和克隆，从而产生治疗人类脑炎的创新方法。将以两个特定目的检验该假设：1）鉴定在MAV-1感染期间导致改变的紧密连接蛋白表达的主要病毒诱导的宿主应答，和2）鉴定负责破坏BBB完整性的先天信号传导和病毒组分。目的1是基于已发表的和初步的数据，即MAV-1减少脑内皮细胞中的紧密连接蛋白表达，并增加脑、星形胶质细胞和小胶质细胞中的基质金属蛋白酶（MMP）表达。已建立的血脑屏障通透性、MMP活性和跨内皮阻力测定将用于检验MMP在感染期间紧密连接蛋白减少中发挥作用的假设。基因敲除、肿瘤治疗和白细胞耗竭小鼠将用于在体内扩展这些发现。在目标2中，将在体内和体外感染中使用病毒突变体和物理改变的病毒颗粒，以测试病毒组分作为信号先天免疫的病原体相关分子模式的假设。为了鉴定MAV-1触发哪种先天免疫信号传导途径，导致BBB破坏，将采用使用小鼠基因敲除的感染的有序方法。拟议的研究是创新的，因为它使用了一种全面的方法来研究由病毒病原体在其天然宿主中引起的BBB破坏，解决了病毒和宿主对脑炎的贡献。这项研究将是重要的，因为它将是第一个在体内的自然宿主特征的BBB破坏的病毒机制，有助于理解特定的病毒基因产物和哺乳动物先天免疫对BBB功能的作用。这种强大的小鼠/MAV-1模型可用于评估治疗脑炎的创新方法。 公共卫生关系：拟议的研究与公共卫生有关，因为确定导致血脑屏障破坏的特定病毒机制将增加对病毒性脑炎发病机制的理解。在中枢神经系统（CNS）的非病毒性疾病中也观察到血脑屏障破坏。此外，功能屏障是有效药物递送的重要障碍。这项研究最终有望促进治疗病毒性脑炎和其他CNS疾病的药理学方法的发展。因此，它解决了NIH的使命，以减少疾病的负担。