Uncovering the Role of the MS4A Gene Family in Alzheimer's Disease

揭示 MS4A 基因家族在阿尔茨海默病中的作用

• 批准号: 10751885
• 负责人: Alexandra Munch
• 金额: $ 4.61万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-14 至 2026-08-13
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10751885
• 关键词: Affect; Age; Alleles; Alzheimer' s Disease; Alzheimer' s disease risk; Alzheimer' s disease therapeutic; Amyloid deposition; Animal Model; Binding; Binding Proteins; Binding Sites; Biological; Biological Assay; Biological Markers; Biological Process; Brain; CCCTC-binding factor; Cell Culture Techniques; Cell Line; Cell physiology; Cells; Central Nervous System; Chromosome 11; Clustered Regularly Interspaced Short Palindromic Repeats; Cognition; Containment; Data Set; Disease; Disease Progression; Disease susceptibility; Drug Targeting; Enhancers; Etiology; Foundations; Future; Gene Cluster; Gene Expression; Gene Family; Genes; Genetic; Genetic Diseases; Genomics; Genotype; Human; Human Genetics; Immune; Immune signaling; Immunologic Receptors; Impaired cognition; In Vitro; Injections; Innate Immune System; Integral Membrane Protein; Knock-out; Light; Macrophage; Maps; Measures; Mediating; Membrane; Memory Loss; Memory impairment; Methods; Microglia; Morphology; Mus; Myelogenous; Myeloid Cells; Nerve Degeneration; Neurodegenerative Disorders; Nucleotides; Outcome; Pathologic; Phagocytosis; Phenotype; Play; Production; Proteins; Public Health; Reactive Oxygen Species; Research; Research Personnel; Risk; Role; Senile Plaques; Signal Transduction; Single Nucleotide Polymorphism; Statistical Study; TREM2 gene; Techniques; Testing; Training; Translating; Transplantation; Validation; Variant; Work; Xenograft Model; Xenograft procedure; amyloid pathology; career; causal variant; cell type; chromatin remodeling; cytokine; disorder risk; drug development; drug discovery; effective therapy; epigenomics; executive function; experimental study; functional genomics; gene function; genetic variant; genome wide association study; humanized mouse; in vitro Model; in vivo; induced pluripotent stem cell; innovation; loss of function; member; mouse model; new therapeutic target; novel; precursor cell; protective allele; response; risk variant; selective expression; single nucleus RNA-sequencing; skills; stem cell model; stem cells; targeted treatment; tau-1; therapeutically effective; transcriptomics

PROJECT SUMMARY Alzheimer’s disease (AD) is a grave neurodegenerative disorder characterized by unrelenting memory loss and deficits in executive function with no effective treatment. Accumulating evidence from genome wide association studies (GWAS) posit that the brain’s innate immune system plays a central role in AD etiology. As the central nervous system’s resident immune cells, microglia have thus emerged as attractive cells to target therapeutically. Such drug targets may lie within the MS4A locus, a region associated with protection from AD, later age-at- onset, and increased levels of sTREM2, a biomarker of microglial activity. This region contains multiple genes within the membrane-spanning 4-domain subfamily A (MS4A) gene cluster, which together encode structurally related transmembrane proteins largely expressed by immune cells whose exact functions are not yet understood. Our work nominated a candidate causal variant within this locus, rs636317, which disrupts an anchor binding site for the chromatin remodeling protein CTCF and is associated with increased expression of MS4A4A and MS4A6A in myeloid cells. This proposal aims to directly test the hypothesis that by modulating MS4A4A and MS4A6A expression via differential CTCF binding, variant rs636317 alters microglial cell function in the context of disease. In AIM 1, I will determine the functional impact of MS4A genes in vitro using CRISPR-edited human induced pluripotent stem cell (iPSC)-derived microglia (iMGL). Given known interactions between MS4A proteins and other immune receptors such as TREM2 and CLEC7A, I will perform targeted functional assays related to immune signaling in iMGLs from two iPSC models: MS4A4A/MS4A6A knockout lines and isogenic lines homozygous for the protective or risk alleles of the candidate causal variant. In AIM 2, I will employ a novel xenotransplantation model involving direct injection of human microglia precursor cells into the mouse brain to evaluate the effect of these genes on cell function in vivo and in the context of disease using 5xFAD chimeric mice. I hypothesize that knocking out MS4A4A and MS4A6A in human microglia promotes protective microglial responses, ameliorating plaque containment and subsequent cognitive decline. Elucidating the function of this gene family and the specific role it plays in AD progression has the potential to greatly impact public health. The proposed research and rigorous training plan outlined here will equip me with the skills needed for a successful future career in neurodegeneration leading an independent research team.

项目摘要 阿尔茨海默病（AD）是一种严重的神经退行性疾病，其特征在于持续的记忆丧失， 执行功能缺陷，没有有效的治疗方法。从全基因组关联中积累证据 研究（GWAS）证实，大脑的先天免疫系统在AD病因学中起核心作用。为中心 作为神经系统的常驻免疫细胞，小胶质细胞因此成为有吸引力的治疗靶细胞。 这些药物靶点可能位于MS 4A基因座内，这是一个与预防AD相关的区域， 发病，和增加的sTREM 2水平，小胶质细胞活性的生物标志物。这个区域包含多个基因 在跨膜4-结构域亚家族A（MS 4A）基因簇内，它们在结构上共同编码 主要由免疫细胞表达的相关跨膜蛋白，其确切功能尚不清楚 明白我们的工作在这个位点中提名了一个候选的因果变异，rs636317，它破坏了一个锚 染色质重塑蛋白CTCF的结合位点，并与MS 4A 4A的表达增加有关 和骨髓细胞中的MS 4A 6A。该提议旨在直接测试通过调节MS 4A 4A和MS 4A 4 B， MS 4A 6A通过差异CTCF结合的表达，变体rs636317改变小胶质细胞功能 疾病。在AIM 1中，我将使用CRISPR编辑的人MS 4A基因在体外确定MS 4A基因的功能影响。 诱导多能干细胞（iPSC）衍生的小胶质细胞（iMGL）。鉴于已知MS 4A蛋白之间的相互作用 和其他免疫受体，如TREM 2和CLEC 7A，我将进行相关的靶向功能测定， 来自两种iPSC模型的iMGL中的免疫信号传导：MS 4A 4A/MS 4A 6A敲除系和等基因系 对于候选致病变体的保护性或风险等位基因是纯合的。在AIM 2中，我将使用一本小说 异种移植模型涉及将人小胶质细胞前体细胞直接注射到小鼠脑中， 使用5xFAD嵌合体评估这些基因在体内和疾病背景下对细胞功能的影响 小鼠我假设敲除人类小胶质细胞中的MS 4A 4A和MS 4A 6A会促进保护性小胶质细胞 反应，改善斑块遏制和随后的认知能力下降。阐明这一功能 基因家族及其在AD进展中发挥的特定作用有可能极大地影响公众健康。的 这里概述的拟议研究和严格的培训计划将使我具备成功工作所需的技能。 未来的职业生涯在神经变性领导一个独立的研究团队。