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

项目总结/摘要 病毒感染现在被认为是渐进性病理性遗忘疾病的危险因素， 支持神经免疫学的新范式，即先天免疫分子的功能是 多种正常CNS功能的调节剂在宿主-病原体免疫过程中诱导神经退行性疾病 应答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疾病的新机制，发现 神经影像学工具和治疗方法的记忆障碍的疾病范围广泛。在我 在一个实验室中，我们意外地发现了CNS浸润单核细胞的作用， 细胞在小胶质细胞介导的突触消除，破坏成人神经发生，并产生神经毒性 星形胶质细胞使用从致脑炎黄病毒、西尼罗河病毒（WNV）和寨卡病毒恢复的新模型 （ZIKV）病毒。我们鉴定了经典的补体蛋白和细胞因子受体信号转导作为新的分子 调节突触消除、神经干细胞（NSC）命运、神经元-小胶质细胞和小胶质细胞- 皮质结构中调节记忆形成和维持的星形胶质细胞串扰。我们还 开始利用新的神经成像方式来开发可用于预测和 监控有记忆障碍风险的病人我们的目标是了解诱导改变的机制 在突触连接和修复方法，有助于破坏神经元网络后恢复 病毒感染。我们的研究计划侧重于三个广泛的领域相关的作用和监管 使用感染后认知的新型小鼠模型研究参与空间学习的先天免疫分子 功能障碍首先，利用遗传学、药理学和PET-MRI，我们将识别和定义分子， T细胞和小胶质细胞或神经元之间的相互作用，驱动驻留细胞的产生和维持。 记忆T细胞促进认知功能障碍。我们将在BSL 3条件下使用scRNAseq来筛选 通过细胞因子或趋化因子受体的细胞特异性缺失靶向的基因和途径，或 施用抑制或增强途径的药剂。我们还将开发诊断工具， ABSL 3 PET-MRI。其次，我们将定义如何小胶质细胞-星形胶质细胞-神经干细胞相互作用的背景下恢复 中枢神经系统病毒感染限制修复和恢复。我们将在小鼠中使用全局和条件基因靶向， 描述了细胞因子在调节星形胶质细胞炎性小体激活的神经细胞类型中的体内作用， 它与神经元和突触恢复关系。我们还将定义先天免疫机制， 并在急性病毒感染和恢复期间使用PET-MRI检测P2 X7 R， 反应性星形胶质细胞的标志物。最后，将利用报告小鼠/命运作图、骨髓嵌合体和 scRNAseq描述髓样细胞在神经毒性星形胶质细胞生成中的精氨酸介导的作用 在WNND恢复期间。第三，我们将研究病毒感染后引发的先天免疫机制， 对皮层连接产生负面影响，并确定神经成像是否可用于预测和跟踪 这个过程具体来说，我们将联合收割机遗传学方法与功能性光学内在信号成像相结合， 血红蛋白和钙动力学来定义对皮质连接产生负面影响的机制。我们 该研究计划将定义突触、T细胞和神经元的分子神经免疫调节的新概念。 和神经胶质细胞的相互作用，为整个神经系统的相关过程的研究提供信息， 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.