Single Cell Analyses of Neuroimmune Dysfunctions in the Thalamocortical Circuit in FTLD

FTLD 丘脑皮质回路神经免疫功能障碍的单细胞分析

• 批准号: 10442528
• 负责人: Eric J Huang
• 金额: $ 64.6万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-15 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10442528
• 关键词: Age; Aging; Alternative Complement Pathway; Astrocytes; Cell Cycle Progression; Cell Death; Cell Nucleus; Cells; Complement; Complement 4b; Dementia; Disease; Disease model; Epigenetic Process; Exhibits; Fluorescent in Situ Hybridization; Frontotemporal Lobar Degenerations; Functional disorder; GRN gene; Gene Expression; Genes; Gliosis; Human; Image; Image Analysis; Knock-out; Lead; Link; Mediating; Microglia; Microscopy; Modeling; Molecular; Molecular Profiling; Mus; Mutation; Natural Immunity; Nerve Degeneration; Neurodegenerative Disorders; Neuroglia; Neuroimmune; Neurons; PGRN gene; Pathology; Pathway Analysis; Patients; Phenotype; Physiological; Process; Property; Protein Deficiency; Proteins; RNA-Binding Proteins; Reporter; Resolution; Role; Sampling; Small Nuclear RNA; Surveys; Synapses; System; Technology; Testing; Thalamic structure; Up-Regulation; Work; age related; aging brain; base; behavioral phenotyping; brain tissue; cell type; cellular imaging; cohort; excitatory neuron; frontal lobe; glial activation; inhibitory neuron; innovation; insight; neural circuit; neuron loss; progenitor; protein TDP-43; reconstruction; response; single cell analysis; single molecule; spatiotemporal; synaptic pruning; transcriptome; transcriptome sequencing; transcriptomics

PROJECT SUMMARY Aberrant glial activation is a prominent feature in neurodegenerative diseases. But, what triggers glial activation in the aging brain and how it contributes to neuronal degeneration remains unclear. The scientific premise of this proposal is based on previous studies that dominant mutations in human Progranulin gene (GRN [gene], PGRN [protein]) cause a drastic reduction in PGRN levels in CSF and brain tissues in patients with frontotemporal lobar degeneration (FTLD), leading to profound gliosis, aggregation of RNA binding protein TDP-43, and neurodegeneration. In support of this idea, our recent studies show that Grn knockout (Grn-/-) mice is a valid model that captures several key disease features in FTLD caused by GRN mutations (FTLD- GRN), including microglial activation, microglia-mediated synaptic pruning and dysfunction in the thalamocortical circuit. Our ongoing work further revealed that Grn-/- mice and FTLD-GRN patients also shows a robust astroglial activation that positively correlates with microglial activation. Similar to Grn-/- microglia, Grn-/- astrocytes exhibit an age-dependent up-regulation of innate immunity genes, including complements C3 and C4b, which together with C1qa from Grn-/- microglia, activate both classical and alternative complement pathways to promote neurodegeneration. Taken together, these results support the hypothesis that PGRN deficiency is a feasible disease model to uncover the intricate neuroimmune interactions and how perturbation to these interactions leads to neuronal degeneration. To test this hypothesis, we propose a comprehensive single cell transcriptomic approach to survey the dynamic changes of glial and neuronal cell types in the thalamocortical circuit that is most severely impacted by PGRN deficiency. This approach will provide critical insights into the intrinsic mechanism of glial activation, neuronal degeneration and neural circuit dysfunction in Grn-/- mice and in FTLD-GRN patients. This innovative strategy involves high throughput profiling of transcriptomic and physiological properties of glia and neurons using droplet-based capture technology, microscopy and dynamic imaging of cell intrinsic physiological responses. These results will provide an unprecedented resolution to directly test the hypothesis that disruptions to the dynamic neuroimmune interactions between microglia, astrocytes and neurons in the thalamocortical circuit lead to neurodegeneration in FTLD caused by PGRN deficiency.

项目摘要 神经胶质细胞异常活化是神经退行性疾病的一个显著特征。但是，是什么触发了神经胶质 老化大脑中的激活以及它如何导致神经元变性仍然不清楚。科学 这一建议的前提是基于先前的研究，即人类颗粒蛋白前体基因的显性突变 (GRN[基因]，PGRN [蛋白质]）导致患者CSF和脑组织中PGRN水平急剧下降 额颞叶变性（FTLD），导致严重的神经胶质增生，RNA结合蛋白聚集 TDP-43和神经变性。为了支持这一观点，我们最近的研究表明，Grn敲除（Grn-/-） 小鼠是一种有效的模型，它捕获了由GRN突变引起的FTLD中的几个关键疾病特征（FTLD- GRN），包括小胶质细胞激活，小胶质细胞介导的突触修剪和功能障碍，在 丘脑皮层回路我们正在进行的工作进一步揭示了Grn-/-小鼠和FTLD-GRN患者也显示出 与小胶质细胞活化正相关的强星形胶质细胞活化。与Grn-/-小胶质细胞类似，Grn-/- 星形胶质细胞表现出先天免疫基因的年龄依赖性上调，包括补体C3和 C4 b与来自Grn-/-小胶质细胞的C1 qa一起激活经典和替代补体 促进神经退化的途径。综上所述，这些结果支持PGRN的假设， 缺乏是一个可行的疾病模型，以揭示复杂的神经免疫相互作用，以及如何干扰 这些相互作用导致神经元变性。为了验证这一假设，我们提出了一个全面的 单细胞转录组学方法来调查神经胶质细胞和神经元细胞类型的动态变化， 丘脑皮质回路中，PGRN缺乏影响最严重。这种方法将提供关键的 深入了解神经胶质细胞活化、神经元变性和神经回路功能障碍的内在机制， Grn-/-小鼠和FTLD-GRN患者。这种创新的策略涉及高通量分析， 使用基于液滴的捕获技术的神经胶质和神经元的转录组学和生理学特性， 显微镜和细胞内在生理反应的动态成像。这些结果将提供一个 前所未有的决议，直接测试的假设，破坏动态神经免疫 小胶质细胞、星形胶质细胞和丘脑皮层回路中的神经元之间的相互作用导致神经变性 PGRN缺乏引起的FTLD。