Bacterial disruption of neuroimmune pathways in a transparent brain

项目摘要/摘要 免疫系统的细胞、细菌和神经元不断地与每一个 人体的表面。最近的研究表明，细菌已经进化出一种机制 与神经系统接触，经常使用调节炎症的吞噬细胞。 神经炎，或神经组织中的炎症，被认为是导致常见的 神经退行性疾病，包括阿尔茨海默病和帕金森氏病，尽管 神经炎症的基本机制仍不完全清楚。长期的 这项新的创新者奖提案的目标是定义 感染期间的神经炎症。创新是我们对尖端技术的改编 斑马鱼分子工具箱(光遗传学、生物传感器、体内生物素化)对宿主病原体的作用 互动。利用这个系统，我们可以对寄主和病原体进行遗传修饰，然后观察 细菌实时入侵透明斑马鱼的大脑。作为病原体，我们使用 激活人类神经炎症的分枝杆菌种类(结核脑膜炎、麻风)和 在斑马鱼身上。我们还开发了新的斑马鱼大脑感染模型，使用人类 从脑膜炎患者中分离出病原体，以确定： 项目1：细菌是如何从血液侵入大脑的？ 方法：明确脑侵袭和血管损伤的内皮机制。 项目2：宿主对病原体因素如何驱动灾难性的脑部炎症？ 方法：体内吞噬细胞的光遗传(光激活)控制。 项目3：宿主对抗病原体因素如何损伤神经元？ 方法：使用生物传感器识别神经元损伤的感染机制。 为了回答这些问题，这项提议结合了免疫生物学和神经生物学 斑马鱼脑感染模型的工具。利用斑马鱼大脑感染的实时成像， 以及对荧光细菌、神经元和吞噬细胞的基因改造，是最早的 炎症和神经变性事件可以以前所未有的细节直接观察到。 这项工作的完成实现了两个目标。首先，它将提供所需的机械性信息 在未被充分研究的脑部感染中介导损伤的宿主细胞和分子 不成比例地影响生活在贫困中的人。这将支持开发新的 限制脑部炎症的疗法。除了感染之外，病毒的基本生物学机制 由感染揭示的神经炎症很可能与许多非传染性疾病有关。 以神经炎症为特征的神经退行性疾病。

Project Summary/Abstract Cells of the immune system, bacteria, and neurons are constantly interacting on every surface of the human body. Recent studies show that bacteria have evolved mechanisms to engage with the nervous system, often using the phagocytes that regulate inflammation. Neuroinflammation, or inflammation in neurological tissue, is thought to contribute to common neurodegenerative conditions, including Alzheimer's disease and Parkinson's disease, although the basic mechanisms of neuroinflammation remain incompletely understood. The long-term objective of this New Innovator Award proposal is to define the molecular mechanisms of neuroinflammation during infection. The innovation is our adaptation of the cutting-edge zebrafish molecular toolkit (optogenetics, biosensors, in vivo biotinylation) to host-pathogen interactions. With this system, we can genetically modify host and pathogen, then observe bacteria invading the transparent zebrafish brain in real-time. As pathogens, we use mycobacterial species that activate neuroinflammation in humans (TB meningitis, leprosy) and in zebrafish. We have also developed new zebrafish brain infection models, using human pathogens isolated from meningitis patients, in order to determine: Project 1: How do bacteria invade the brain from the blood? Approach: Define the endothelial mechanisms of brain invasion and vascular injury. Project 2: How do host versus pathogen factors drive catastrophic brain inflammation? Approach: Optogenetic (light-activated) control of phagocytes in vivo. Project 3: How do host versus pathogen factors injure neurons? Approach: Identifying infectious mechanisms of neuronal injury using biosensors. To answer these questions, this proposal combines immunobiology and neurobiology tools with brain infection models in zebrafish. Using live imaging of zebrafish brain infection, and genetic modification of fluorescent bacteria, neurons, and phagocytes, the earliest inflammatory and neurodegenerative events can be directly observed in unprecedented detail. Completion of this work fulfills two goals. First, it will provide needed mechanistic information on the host cells and molecules that mediate injury in understudied brain infections that disproportionately affect people living in poverty. This will support the goal of developing new therapies that limit brain inflammation. Beyond infection, the basic biological mechanisms of neuroinflammation, revealed by infection, will likely be relevant to the many non-infectious neurodegenerative conditions that are characterized by neuroinflammation.