Microglia contribution to disease pathogenesis in C9orf72 ALS/FTD

小胶质细胞对 C9orf72 ALS/FTD 疾病发病机制的贡献

• 批准号: 10228403
• 负责人: Rita Sattler
• 金额: $ 83.62万
• 依托单位: ST. JOSEPH'S HOSPITAL AND MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10228403
• 关键词: ALS patients; Affect; Alzheimer' s Disease; Alzheimer' s disease related dementia; Amyotrophic Lateral Sclerosis; Area; Astrocytes; Autopsy; Brain; Brain region; C9ORF72; Candidate Disease Gene; Cell Differentiation process; Cell Line; Cells; Clinical; Coculture Techniques; Communication; Data; Data Set; Dementia; Dementia With Amyotrophic Lateral Sclerosis; Department of Defense; Development; Dipeptides; Disease; Drug Targeting; Etiology; Executive Dysfunction; Expression Profiling; Frontotemporal Dementia; Functional disorder; Funding; Future; Gene Expression; Gene Expression Profile; Gene Expression Profiling; Gene Proteins; Genes; Goals; Hot Spot; Human; Immune; Immunohistochemistry; Impaired cognition; In Vitro; Investigation; Knowledge; Label; Laboratories; Lysosomes; Maintenance; Measures; Microglia; Modeling; Molecular; Morphology; Motor Neurons; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Neurofibrillary Tangles; Neuronal Dysfunction; Neurons; Outcome; PGRN gene; Pathogenesis; Pathologic; Pathology; Patients; Phagocytes; Phenotype; Play; Prefrontal Cortex; Process; Property; Prosencephalon; Proteins; RNA; Regulation; Reporting; Role; Small Nuclear RNA; Specificity; Symptoms; Synapses; System; Time; Tissue-Specific Gene Expression; Tissues; Validation; Variant; cell type; chemokine; clinical Diagnosis; cytokine; density; disease phenotype; drug discovery; executive function; frontotemporal lobar dementia-amyotrophic lateral sclerosis; genetic profiling; induced pluripotent stem cell; molecular phenotype; neuron loss; neuronal excitability; neuronal survival; novel; novel therapeutics; patient population; patient subsets; protein TDP-43; protein expression; relating to nervous system; single-cell RNA sequencing; stem cell differentiation; transcriptome; transcriptome sequencing

Project Abstract The role of microglia in the C9orf72 (C9) amyotrophic lateral sclerosis (ALS)/ frontotemporal dementia (FTD) disease spectrum remains poorly understood. Early investigations found that microglia activation was significantly higher in ALS with dementia and impaired executive function, suggesting that microglia activation correlates with FTD-like symptoms in ALS. More recent neuropathologic examinations of microglia in FTLD patient autopsy brains with mutations in progranulin versus C9orf72 concluded that the observed microglia dysfunction was different between the two genetically different patient subgroups suggesting specificity of microglia dysfunction depending on the etiology of the patient population. One interesting aspect of microglia- neuron communication is the role of microglia in the maintenance and refinement of synaptic networks through the selective pruning of synapses, which occurs predominantly during development but has been shown to also be triggered in Alzheimer's disease (AD) and related dementias, including FTD. The degree of synapse loss in AD strongly correlates with cognitive decline, even more than the amount of plaque, tangles or neuronal loss, and a recent study of ALS postmortem tissue confirmed increased synapse loss in the prefrontal cortex of patients with reported cognitive impairments. Our laboratory has preliminary data supporting the hypothesis that there is an altered neural-immune interaction in the cortical forebrain regions of C9orf72 patients with confirmed FTD in which microglia and neurons modify each other's function. Using patient-derived hiPSC microglia and cortical neurons, we are able to show that C9 patient-derived hiPSC microglia mono-cultures do have intrinsic phenotypes, including altered gene profiles, phagocytic activities and lysosomal function. Most interestingly, preliminary data suggests that C9 microglia do regulate neuronal excitability and survival of C9 iPSC neurons. To further investigate the role and contribution of microglia in C9 cortical degeneration, we propose to thoroughly investigate the intrinsic properties of C9 hiPSC-microglia (from all patient subgroups: FTD, FTD/ALS, ALS; Aim1). For the first time, we will then co-culture these microglia with C9 and healthy control hiPSC cortical neurons to better understand the co-regulation between these two cell types (Aim 2). Finally, in the third aim, we will study microglia activation and pathology in C9 patient postmortem autopsy tissue. This will include cell-type specific genetic profiling from existing snRNA seq data sets, immunohistochemistry of microgliosis and multi-label immunostaining for microglial-specific candidate genes/proteins in conjunction with C9 neuronal disease pathology markers (TDP-43 and C9 DPRs) to gain novel knowledge on whether microglia are preferentially altered in close vicinity to neuronal pathologies.

项目摘要 小胶质细胞在C9 orf 72（C9）肌萎缩侧索硬化（ALS）/额颞叶痴呆（FTD）中的作用 疾病谱仍然知之甚少。早期的研究发现，小胶质细胞的激活是 在伴有痴呆和执行功能受损的ALS患者中， 与肌萎缩侧索硬化症中的FTD样症状相关。FTLD中小胶质细胞的最新神经病理学检查 对具有颗粒蛋白前体与C9 orf 72突变的患者尸检大脑得出结论，观察到的小胶质细胞 两个遗传不同的患者亚组之间的功能障碍是不同的，这表明 小胶质细胞功能障碍取决于患者人群的病因。小胶质细胞的一个有趣的方面- 神经元通讯是小胶质细胞在维持和完善突触网络中的作用， 突触的选择性修剪，主要发生在发育过程中，但也被证明是 在阿尔茨海默病（AD）和相关痴呆症（包括FTD）中触发。突触丢失的程度 AD与认知能力下降密切相关，甚至超过斑块、缠结或神经元损失的数量， 最近一项对ALS死后组织的研究证实， 报告有认知障碍的患者。我们的实验室有初步数据支持这一假设， 在C9 orf 72患者的皮质前脑区域存在改变的神经免疫相互作用， 证实了FTD，其中小胶质细胞和神经元改变彼此的功能。使用患者来源的hiPSC 我们能够证明，C9患者来源的hiPSC小胶质细胞单培养物确实能够诱导小胶质细胞和皮质神经元的分化。 具有内在表型，包括改变的基因谱、吞噬活性和溶酶体功能。最 有趣的是，初步数据表明C9小胶质细胞确实调节神经元的兴奋性和C9的存活， iPSC神经元。为了进一步研究小胶质细胞在C9皮质变性中的作用和贡献，我们 建议彻底研究C9 hiPSC-小胶质细胞的内在特性（来自所有患者亚组：FTD， FTD/ALS，ALS; Aim 1）。第一次，我们将这些小胶质细胞与C9和健康对照共培养 hiPSC皮质神经元，以更好地理解这两种细胞类型之间的共调节（目的2）。最后在 第三个目的是研究C9患者尸检组织中小胶质细胞的活化和病理变化。这将 包括来自现有snRNAseq数据集细胞类型特异性遗传分析， 小胶质细胞增生和小胶质细胞特异性候选基因/蛋白质的多标记免疫染色， C9神经元疾病病理学标志物（TDP-43和C9 DPR），以获得关于小胶质细胞是否 优先在神经元病变附近改变。