Regulation of diverse microglial phenotypes in neurodegeneration

神经退行性变中不同小胶质细胞表型的调节

• 批准号: 10901024
• 负责人: SUMAN JAYADEV
• 金额: $ 87.14万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-15 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10901024
• 关键词: Address; Adult; Age; Aging; Alleles; Alzheimer' s Disease; Alzheimer' s disease pathology; Amyloid beta-Protein; Autopsy; Behavior; Brain; Brain Diseases; Cell Nucleus; Cell physiology; Cells; Cessation of life; Chromatin; Communication; Complex; Complication; DNA; DNA Damage; DNA Methylation; Data; Data Set; Development; Disease; Early Onset Alzheimer Disease; Elderly; Etiology; Experimental Designs; Freezing; Genes; Genetic Transcription; Goals; Heterogeneity; Human; Immune; Immune response; Impairment; In Vitro; Individual; Inflammasome; Inflammatory; Interferons; Intervention; Late Onset Alzheimer Disease; Life; Light; Link; Literature; Maps; Measures; Microglia; Microscopy; Molecular Profiling; Morphology; Myelin; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Nucleic Acids; Pathogenesis; Pathogenicity; Pathologic; Pathology; Pathway interactions; Peptide Initiation Factors; Phenotype; Population; Process; RNA; Regulation; Regulator Genes; Regulatory Element; Role; Sampling; Signal Transduction; Site; Stimulus; Syndrome; Testing; Therapeutic; Time; Tissues; Toxic effect; Variant; Viral; age related; aged; aging brain; brain cell; brain tissue; cell type; cohort; early onset; epigenomics; familial Alzheimer disease; frontal lobe; gene network; gene regulatory network; genetic variant; induced pluripotent stem cell; insight; molecular phenotype; nerve stem cell; network dysfunction; neurotoxicity; normal aging; nucleic acid localization; pathogen; presenilin-1; presenilin-2; response; single nucleus RNA-sequencing; stem cell model; targeted treatment; tau-1; therapeutic candidate; therapeutic target; therapeutically effective; three-dimensional visualization; transcriptome; transcriptome sequencing; transcriptomics; viral DNA

Alzheimer disease is a multifactorial process that has thus far been challenging to therapeutically target. A large body of literature supports a key role for microglia, the innate immune cells of the brain, in AD pathogenesis. Manipulating microglial activity may be one tractable AD intervention however microglia roles in AD are complex. Microglia orchestrate a suite of functions in the homeostatic, aged and diseased brain. Understanding which of these microglial phenotypes contribute to AD and how these phenotypes are regulated is necessary to develop precise therapies for AD. By performing single nucleus RNAseq (snRNAseq) on more than 5,000 microglia per individual from a cohort of 22 late-onset AD (LOAD) and age-matched control autopsy samples we have identified microglia clusters significantly associated with AD. One of these is specifically enriched in genes in the endolysosomal network (ELN), DNA damage response pathways and Type 1 interferon signaling. While these pathologies have been documented in AD, they are also influenced by aging, highlighting the complication of studying a late age neurodegenerative disease. In contrast, individuals with early onset familial AD (EOFAD), driven by genetic variants develop AD early in life and at time of death, EOFAD individuals have fewer systemic and brain aging changes than those with LOAD. We hypothesize that response to DNA damage exacerbated by a dysfunctional ELN contributes to AD pathogenesis independent of age. In this study we will leverage our unique cohorts of frozen brain tissue and human induced pluripotent stem cell (hiPSC) in 3 Aims. We will determine microglial molecular profiles (Aim 1) and spatial organization (Aim 2) with and without AD across the spectrum of young to older adult age. We will functionally test our hypothesis using hiPSC models, which lack age related changes (Aim 3). We propose to generate microglial transcriptomic, open chromatin and DNA methylation profiles building gene networks from frozen cortical samples of 19 EOFAD individuals who carry pathogenic variants in PSEN1/PSEN2 or APP and compare them to cortical samples from 35 age-matched unaffected controls aged 25 to 60 years and 10 controls aged 65-75 years. We will map the changes associated with age alone in microglia profiles across the adult age in the 25yr-75 yr control cohort. We will leverage our existing older control and LOAD snRNAseq dataset as another comparison and nominate which microglial changes appear in the presence of AD pathology, age alone, and those that are exacerbated by the presence of both AD and age. To functionally measure the significance of the AD phenotypes we have identified we will use hiPSC derived microglia and neurons to test the hypothesis that ELN dysfunction contributes to damage and accumulation of nucleic acids contributing to neuronal toxicity. These integrated omics and in vitro studies evaluating human microglia across the adult age span and AD pathology will identify and functionally test factors regulating microglial phenotypes that can inform effective therapeutic targeting for both EOFAD and LOAD.

阿尔茨海默病是一个多因素的过程，迄今为止一直具有挑战性的治疗目标。一 大量文献支持小胶质细胞（大脑的先天免疫细胞）在AD中的关键作用 发病机制操纵小胶质细胞的活动可能是一种易于处理的AD干预，然而小胶质细胞在AD中的作用。 AD很复杂。小胶质细胞在稳态、衰老和患病的大脑中协调一系列功能。 了解这些小胶质细胞表型中的哪些有助于AD以及这些表型如何调节 是开发精确的AD疗法所必需的。通过在更多的细胞上进行单核RNAseq（snRNAseq）， 来自22例迟发性AD（LOAD）队列和年龄匹配的对照尸检的每个个体超过5，000个小胶质细胞 我们已经确定了与AD显著相关的小胶质细胞簇。其中之一就是 富含内溶酶体网络（ELN）、DNA损伤反应途径和1型 干扰素信号传导虽然这些病理学在AD中已有记载，但它们也受到衰老的影响， 强调了研究老年神经退行性疾病的复杂性。相反， 由遗传变异驱动的早发性家族性AD（EOFAD）在生命早期和死亡时发展为AD， EOFAD个体的全身和大脑老化变化比LOAD个体少。我们假设 对由ELN功能障碍加重的DNA损伤的反应导致AD发病机制独立于 年龄在这项研究中，我们将利用我们独特的冷冻脑组织和人类诱导多能 干细胞（hiPSC）在3个目标中。我们将确定小胶质细胞的分子概况（目标1）和空间组织 (Aim 2）在年轻人到老年人的年龄范围内有和没有AD。我们将在功能上测试 使用缺乏年龄相关变化的hiPSC模型的假设（目标3）。我们建议用小胶质细胞 转录组学、开放染色质和DNA甲基化图谱从冷冻皮质构建基因网络 19名携带PSEN 1/PSEN 2或APP致病性变异的EOFAD个体的样本，并将它们进行比较 来自35名年龄匹配的25 - 60岁未受影响的对照组和10名65-75岁的对照组的皮质样本 年我们将绘制在成人年龄的小胶质细胞概况中与年龄相关的变化， 25 -75岁对照队列。我们将利用现有的旧控件和LOAD snRNAseq数据集作为另一个 比较和提名哪些小胶质细胞的变化出现在存在AD病理，年龄单独， 这些都是由AD和年龄的存在加剧。从功能上衡量 我们将使用hiPSC衍生的小胶质细胞和神经元来检验我们已经鉴定的AD表型 ELN功能障碍导致核酸的损伤和积累，从而导致神经元毒性。 这些综合的组学和体外研究评估了成人年龄段和AD患者的人类小胶质细胞， 病理学将识别和功能测试调节小胶质细胞表型的因子， 用于EOFAD和LOAD的治疗靶向。