Research Program Award (R35 Clinical Trial Optional) - Dr. Robyn Klein NINDS

项目摘要/摘要 病毒感染现在被认为是进行性病理性遗忘疾病的危险因素， 支持神经免疫学中的一种新范式，即天然免疫分子的功能是 多种正常中枢神经系统功能调节物在宿主病原体过程中诱发神经退行性疾病 回应。通过免疫学的多学科棱镜研究病毒介导的认知功能障碍， 神经科学和病毒学对于识别新的疾病机制至关重要，发现 各种记忆障碍疾病的神经成像工具和治疗方法。在我的 我们在实验室中对中枢神经系统渗透单个核细胞的作用做出了意想不到的、改变范式的发现 小胶质细胞介导的突触消除、干扰成人神经发生和产生神经毒性的细胞 从西尼罗河病毒和寨卡病毒中恢复脑源性黄病毒的星形胶质细胞 (ZIKV)病毒。我们发现经典的补体蛋白和细胞因子受体信号是新的分子 调节突触消除的介质，神经干细胞(NSC)的命运，神经元-小胶质细胞和小胶质细胞- 星形胶质细胞在调节记忆形成和维持的皮质结构中的串扰。我们还有 开始利用新的神经成像手段开发生物标记物，可以用来预测和 监测有记忆障碍风险的患者。我们的目标是了解引起变化的机制。 在突触连接和修复方法中，恢复后会导致神经元网络的破坏 不受病毒感染。我们的研究计划集中在三个广泛的领域，涉及到 利用感染后新的小鼠认知模型研究参与空间学习的先天免疫分子 功能障碍。首先，使用遗传学、药理学和PET-MRI，我们将识别和定义分子 T细胞与小胶质细胞或神经元之间的相互作用推动了常驻神经元的产生和维持 促进认知功能障碍的记忆T细胞。我们将在BSL3条件下使用scRNAseq来筛选 通过细胞特异性删除细胞因子或趋化因子受体而靶向的基因和途径，或 给药抑制或增强通路的药物。我们还将开发诊断工具，使用 ABSL3型PET-MRI。其次，我们将定义小胶质细胞-星形胶质细胞-神经干细胞在恢复过程中的相互作用 来自中枢神经系统的病毒感染限制了修复和恢复。我们将在小鼠身上使用全局和有条件的基因打靶来 阐明细胞因子在调节星形胶质细胞炎性小体激活和神经细胞类型中的体内作用 它与神经元和突触恢复的关系。我们还将定义先天免疫机制 在急性病毒感染和康复期间，通过PET-MRI检测P2X7R，a 反应性星形胶质细胞的标志物。最后，将利用报告鼠/命运图谱、骨髓嵌合体和 ScRNAseq研究髓系细胞在神经毒性星形胶质细胞生成中的细胞因子介导作用 在WNND恢复期间。第三，我们将研究在病毒感染后触发的先天免疫机制 对皮质连通性产生负面影响，并确定神经成像是否可用于预测和跟踪 这一过程。具体地说，我们将把遗传方法与功能性光学固有信号成像结合起来 血红蛋白和钙的动力学，以确定对皮质连接产生负面影响的机制。我们的 研究计划将定义突触的分子神经免疫调节的新概念，T细胞 和神经胶质细胞的相互作用，为整个神经系统的相关过程研究提供信息，并可能 增强我们对神经退行性疾病和其他记忆障碍的理解。

PROJECT SUMMARY/ABSTRACT Viral infections are now recognized as risk factors for diseases of progressive pathological forgetting, supporting a new paradigm in neuroimmunology whereby innate immune molecules that function as modulators of a variety of normal CNS functions induce neurodegenerative diseases during host-pathogen responses. Studying virus-mediated cognitive dysfunction through the multidisciplinary prism of immunology, neuroscience, and virology is critical for the identification of novel mechanisms of disease, discovery of neuroimaging tools and therapeutic treatments for a wide range of diseases of memory disorder. In my laboratory we made unanticipated, paradigm-shifting discoveries of the roles of CNS infiltrating mononuclear cells in microglial-mediated synapse elimination, disrupted adult neurogenesis, and generation of neurotoxic astrocytes using novel models of recovery from encephalitogenic flaviviruses, West Nile (WNV) and Zika (ZIKV) viruses. We identified classical complement proteins and cytokine receptor signaling as novel molecular mediators that regulate synapse elimination, neural stem cell (NSC) fates, neuron-microglia and microglia- astrocyte crosstalk within cortical structures that regulate memory formation and maintenance. We have also begun leveraging novel neuroimaging modalities to develop biomarkers that may be used to predict and monitor patients at risk for memory disorders. Our aim is to understand the mechanisms that induce alterations in synaptic connections and methods of repair that contribute to disruption of neuronal networks after recovery from viral infections. Our research program focuses on three broad areas related to the roles and regulation of innate immune molecules involved in spatial learning using novel murine models of post-infectious cognitive dysfunction. First, using genetic, pharmacologic and PET-MRI, we will identify and define molecular interactions between T cells and microglia or neurons that drive the generation and maintenance of resident memory T cells that promote cognitive dysfunction. We will use scRNAseq under BSL3 conditions to screen for genes and pathways to be targeted via cell-specific deletion of cytokine or chemokine receptors, or administration of agents that inhibit or enhance pathways. We will also develop diagnostic tools that employ ABSL3 PET-MRI. Second, we will define how microglia-astrocyte-NSC interactions in the context of recovery from CNS viral infections limit repair and recovery. We will use global and conditional gene targeting in mice to delineate the in vivo roles of cytokines in neural cell types that regulate astrocyte inflammasome activation and its relationship to neuronal and synapse recovery. We will also define innate immune mechanisms that direct and maintain astrogenosis during acute viral infection and recovery using PET-MRI detection of P2X7R, a marker of reactive astrocytes. Finally, will utilize reporter mice/fate mapping, bone marrow chimeras and scRNAseq to delineate the cytokine-mediated roles of myeloid cells in the generation of neurotoxic astrocytes during WNND recovery. Third, we will examine innate immune mechanisms triggered after viral infections that negatively impact cortical connectivity and determine whether neuroimaging can be used to predict and follow this process. Specifically, we will combine genetic approaches with functional optical intrinsic signal imaging of hemoglobin and calcium dynamics to define mechanisms that negatively impact cortical connectivity. Our research program will define new concepts in the molecular neuroimmunological regulation of synapses, T cell and glial interactions, inform studies of related processes throughout the nervous systems, and will likely enhance our understanding of neurodegenerative and other disorders of memory.