Modeling Alzheimer's Disease in Hispanic Latino populations using human cortical organoids

使用人类皮质类器官模拟西班牙裔拉丁裔人群的阿尔茨海默病

• 批准号: 10680168
• 负责人: Karina K Meyer-Acosta
• 金额: $ 3.89万
• 依托单位: UNIVERSITY OF TEXAS SAN ANTONIO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10680168
• 关键词: 3-Dimensional; Abeta synthesis; Address; Alleles; Alzheimer' s Disease; Alzheimer' s disease model; Alzheimer' s disease pathology; Alzheimer' s disease patient; Alzheimer' s disease related dementia; Alzheimer' s disease risk; Biological Assay; Biological Models; Biology; Brain; Cell Death; Cells; Central America; Cerebrum; Cessation of life; Characteristics; Clinical; Clustered Regularly Interspaced Short Palindromic Repeats; Data; Disease; Disease model; Dorsal; Enzyme-Linked Immunosorbent Assay; Ethnic Origin; Ethnic Population; Fellowship; Gene Expression; Genes; Genetic; Genetic Risk; Genetic Transcription; Genetic Variation; Genetic study; Genome; Genotype; Geography; Growth; Heritability; Hispanic; Hispanic ancestry; Human; Immunohistochemistry; Impaired cognition; Impairment; In Vitro; Individual; Latino Population; Learning; Measures; Mediating; Methods; Mexican; Mexican Americans; Molecular; Neuroglia; Neurons; Not Hispanic or Latino; Organoids; Pathologic; Pathology; Pathway interactions; Patients; Pattern; Phenotype; Physiological; Population; Population Heterogeneity; Proliferating; Proteins; Risk; Role; Scientist; South American; Support Groups; Testing; Training; Variant; Western Blotting; apolipoprotein E-3; apolipoprotein E-4; cell type; differential expression; disease phenotype; disorder risk; ethnic diversity; excitatory neuron; experimental study; genetic manipulation; genetic risk factor; genome wide association study; health disparity; high risk; induced pluripotent stem cell; induced pluripotent stem cell technology; inhibitory neuron; insight; multi-ethnic; new therapeutic target; novel; protective effect; protein expression; risk variant; skills; stem; stem cell technology; tau-1; therapeutic target; transcriptome sequencing

Project Summary/Abstract Hispanic Latinos (HLs) have the highest risk of developing Alzheimer’s disease (AD) and related dementias, the highest proportion of any ethnic group in the US. In genome-wide association studies (GWAS) conducted mostly in non-Hispanic white (NHW) individuals, Apolipoprotein E4 (APOE4) was established as the leading AD genetic risk factor, increasing risk 3-12 fold compared to the non-risk allele, APOE3. In HLs however, there is discordant evidence about the association of APOE4 with AD which is at least partially attributed to the genetic diversity of HLs stemming from widespread geographic origins. GWAS in large HL populations identified ancestry native to Central America, the primary ancestry of Hispanic Mexican Americans (HMA), have little to no AD association with APOE4. Studies further suggest that inheritance of APOE4 allele from native ancestor may not increase AD risk to the same extent as that observed in NHW. It is postulated that genetic variation, possibly regulatory, either local to APOE allele, or across the genome, modifies APOE4 biology. Recently, genetic variation local to APOE was shown to dominantly influence gene transcription and APOE expression independent of APOE genotype. Gaining insight on the molecular basis by which HMA background modifies APOE4 biology would identify protective mechanisms against AD. My central hypothesis is that APOE4 will be associated with AD-related phenotypes in cortical organoids with NHW ancestry, but not with HMA ancestry, or to a lesser extent. Since AD develops decades before cognitive decline and ethnic variation is human-specific, I will test my hypothesis in 3D cortical organoids. I will generate excitatory neuron-enriched human cortical organoids (hCO), and inhibitory neuron-enriched human subpallial organoids (hSO) to explore neuron subtype-specific differences in AD-related phenotypes. To investigate cellular phenotypes mediated by APOE4 with respect to genetic background, I will 1) characterize the effect of APOE4 on AD-related cellular phenotypes within NHW background, and 2) determine the effect of HMA background on APOE4 mediated phenotypes and gene transcription. My preliminary data suggests that the APOE4 allele reduces growth and upregulates APOE expression in both hCO and hSO compared to organoids carrying the non-risk allele, APOE3. Aim 1 will explore the cellular basis contributing to size (differentiation, maturation, and cell death) and characterize AD-related pathology by immunostaining and protein expression assays. To control for patient background and assess the specific effects of APOE4 genotype and genetic background, I will gene-edit APOE3 to APOE4 in iPSCs with NHW and HMA backgrounds. In Aim 2, I will determine the phenotypic and transcriptional changes associated with HMA background on APOE4- mediated AD-related phenotypes. Under this fellowship, I will expand my molecular toolkit and in vitro disease modeling and hone my skills as a molecular neuroscientist. I will also strengthen my analytical skills and learn new methods to probe gene expression by training under my sponsor and a supporting group of scientists.

项目概要/摘要 西班牙裔拉丁裔 (HL) 患阿尔茨海默病 (AD) 和相关痴呆症的风险最高 是美国所有族裔中比例最高的。在全基因组关联研究（GWAS）中，大部分进行 在非西班牙裔白人 (NHW) 个体中，载脂蛋白 E4 (APOE4) 被确定为主要的 AD 基因 风险因素，与非风险等位基因 APOE3 相比，风险增加 3-12 倍。然而，在 HL 中，存在不一致的情况 APOE4 与 AD 相关的证据至少部分归因于遗传多样性 HL 源于广泛的地理起源。大型 HL 人群中的 GWAS 确定了原产于 中美洲是西班牙裔墨西哥裔美国人 (HMA) 的主要祖先，几乎没有 AD 关联 与 APOE4。研究进一步表明，从本地祖先遗传 APOE4 等位基因可能不会增加 AD 风险程度与 NHW 中观察到的风险程度相同。据推测，遗传变异，可能是调节性的， APOE 等位基因局部或整个基因组改变 APOE4 生物学。最近，APOE 局部遗传变异 研究显示，其主要影响基因转录和 APOE 表达，与 APOE 基因型无关。 深入了解 HMA 背景改变 APOE4 生物学的分子基础将确定 AD 的保护机制。我的中心假设是 APOE4 与 AD 相关 具有 NHW 血统但不具有 HMA 血统的皮质类器官的表型，或程度较小。自公元 认知衰退和种族差异是人类特有的，几十年前就已经出现了，我将在 3D 中检验我的假设 皮质类器官。我将生成富含兴奋性神经元的人类皮质类器官（hCO）和抑制性类器官 富含神经元的人皮下类器官（hSO）探索 AD 相关神经元亚型特异性差异 表型。为了研究 APOE4 介导的细胞表型的遗传背景，我将 1) 表征 NHW 背景下 APOE4 对 AD 相关细胞表型的影响，以及 2) 确定 HMA 背景对 APOE4 介导的表型和基因转录的影响。我的初步 数据表明 APOE4 等位基因会降低 hCO 和 hSO 中的生长并上调 APOE 表达 与携带非风险等位基因 APOE3 的类器官相比。目标 1 将探索有助于 大小（分化、成熟和细胞死亡）并通过免疫染色和表征 AD 相关病理学 蛋白质表达测定。控制患者背景并评估 APOE4 基因型的具体影响 和遗传背景，我将在具有 NHW 和 HMA 背景的 iPSC 中将 APOE3 基因编辑为 APOE4。瞄准 2，我将确定与APOE4-上的HMA背景相关的表型和转录变化 介导的 AD 相关表型。在这个奖学金下，我将扩展我的分子工具包和体外疾病 建模并磨练我作为分子神经科学家的技能。我也会加强我的分析能力并学习 通过在我的赞助人和支持的科学家小组的培训下探索基因表达的新方法。