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.

项目总结/摘要 西班牙裔拉丁美洲人（HL）患阿尔茨海默病（AD）和相关痴呆症的风险最高， 是美国所有种族中比例最高的。在全基因组关联研究（GWAS）中， 在非西班牙裔白色（NHW）个体中，载脂蛋白E4（APOE 4）被确定为AD的主要遗传因素 风险因子，与非风险等位基因APOE 3相比，风险增加3-12倍。然而，在HL中， 关于APOE 4与AD相关的证据，至少部分归因于以下基因的遗传多样性： HLs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 APOE 4研究进一步表明，来自本地祖先的APOE 4等位基因的遗传可能不会增加AD 风险与NHW中观察到的风险相同。据推测，遗传变异，可能是调节， APOE等位基因局部或跨基因组修饰APOE 4生物学。最近，APOE局部的遗传变异 结果表明，基因转录和APOE表达的主要影响独立的APOE基因型。 深入了解HMA背景修饰APOE 4生物学的分子基础， AD的保护机制。我的中心假设是，APOE 4将与AD相关的 在具有NHW血统的皮质类器官中，表型，但不具有HMA血统，或在较小程度上。自公元 在认知能力下降和种族差异是人类特有的几十年前，我将在3D中验证我的假设 皮质类器官我将产生兴奋性神经元富集的人类皮质类器官（hCO）， 神经元富集的人类苍白球下类器官（hSO），以探索AD相关神经元亚型特异性差异 表型为了研究APOE 4介导的细胞表型与遗传背景的关系，我将 1)表征APOE 4对NHW背景下AD相关细胞表型的影响，以及2） 确定HMA背景对APOE 4介导的表型和基因转录的影响。我的初步 数据表明，在hCO和hSO中，APOE 4等位基因降低生长并上调APOE表达 与携带非风险等位基因APOE 3的类器官相比。目标1将探索细胞基础， 大小（分化、成熟和细胞死亡）并通过免疫染色表征AD相关病理学， 蛋白质表达测定。控制患者背景并评估APOE 4基因型的特异性影响 和遗传背景，我将在具有NHW和HMA背景的iPSC中将APOE 3基因编辑为APOE 4。在Aim中 2，我将确定与APOE 4上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，我将扩大我的分子工具包和体外疾病 建模和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， 在我的赞助人和一个支持小组的科学家的训练下，探索基因表达的新方法。