Elucidating AD genotype-phenotype relationships using genetics of human IPS cells

利用人类 IPS 细胞遗传学阐明 AD 基因型-表型关系

• 批准号: 8758050
• 负责人: Lawrence S. Goldstein
• 金额: $ 193.6万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8758050
• 关键词: Address; Alzheimer' s Disease; Astrocytes; Biochemical; Candidate Disease Gene; Cell Line; Cell model; Cells; Clinical Data; Data; Diagnostic; Disease; Disease Pathway; Down Syndrome; Elements; Endocytosis; Event; Exhibits; Frequencies; Gene Expression; Genes; Genetic; Genome; Genomics; Genotype; Heritability; Human; Human Genetics; In Vitro; Individual; Lesion; Light; Link; Modeling; Mutation; Neuroglia; Neurons; Pathology; Pathway interactions; Patients; Phenotype; Play; Population; Research; Risk Factors; Role; Site; Testing; Therapeutic; Variant; Work; cell type; disease phenotype; familial Alzheimer disease; gene function; genetic risk factor; genetic variant; genome wide association study; induced pluripotent stem cell; presenilin; public health relevance; research study; secretase; social; stem cell technology; tau Proteins; tau phosphorylation; therapy development; trafficking

DESCRIPTION (provided by applicant): Alzheimer's disease (AD) is common, devastating, and creates enormous social and financial burdens. At present, no effective disease-modifying AD treatment is available or imminent, in part because we lack a complete understanding of the cellular mechanisms and pathways that fail in human neurons and glial cells during disease, and in part because we don't adequately understand how common genetic variants alter human neuronal and glial phenotypes. Here we propose to test whether APP and PS mutations generated in common genetic backgrounds in human induced pluripotent stem cells (hIPSC) generate the same early neuronal phenotypes and then to investigate the extent to which a candidate set of genes identified by GWAS studies generate comparable phenotypes when reduced, increased, or altered by naturally occurring variants. To tackle both problems, we propose unique applications of hIPSC technology to 1) dissect how FAD mutations alter key pathways and then 2) to test how individual genetic background and identified risk factors predispose to SAD biochemical phenotypes in human neurons and astrocytes. Where possible, we will link the in vitro information to clinical data on individual patients and to post-mortem pathology from the UCSD ADRC. The analysis of hIPSC lines from SAD patients will be crucial to probe how common genetic risk factors act in neurons and astrocytes and will also give an initial estimate of the frequency of genomes in SAD patients and controls that cause relevant SAD phenotypes in neural cells differentiated in vitro. This frequency estimate will help address the important long-term question of whether hIPSC lines can be used to predict the likelihood that a given individual will develop SAD, i.e., to generate a predictive genomic/hIPSC diagnostic for SAD. This proposal capitalizes upon previous work from us and others that analyzed hIPSC lines from patients carrying an APP duplication (APPDp) or trisomy 21. Both situations appear to cause FAD by increasing APP expression by 50% in an otherwise euploid genome. Neurons made from these hIPSC lines exhibit typical AD biochemical alterations including elevated A¿, elevated activation of GSK3, and elevated phosphorylation of tau at a proposed pathological site. We also found that APPV717F but not PS1dE9 mutations cause elevated p-tau levels. Thus, early neuronal phenotypes of APP and presenilin mutations might be different raising the possibility that there may be multiple early pathogenic pathways that can be studied using hIPSC technology. We also found that hIPSC studies can elucidate how one common genetic risk factor, SORL1, acts in human neurons. We thus propose three specific aims: 1) Test the hypothesis that APP, PS1, and ¿-secretase mutations trigger the same early events in human neurons and astrocytes leading to downstream biochemical pathology typical of AD. 2) Test the hypothesis that genes identified as risk factors in GWAS studies generate AD phenotypes and altered endocytosis, trafficking, or transport when over or underexpressed. 3) Test the hypothesis that common genetic variants identified in GWAS studies act by altering gene expression in neurons or astrocytes.

描述（由适用提供）：阿尔茨海默氏病（AD）是常见的，毁灭性的，并创造了增强的社会和金融燃烧。目前，尚无有效的疾病修改AD治疗，部分原因是我们缺乏对疾病期间人类神经元和神经胶质细胞失败的细胞机制和途径的完全理解，部分原因是我们不充分了解常见的遗传变异如何改变人类神经元和神经胶质表型。在这里，我们建议测试人类诱导的多能干细胞（HIPSC）在常见遗传背景中产生的APP和PS突变是否会产生相同的早期神经元表型，然后研究GWAS研究鉴定出的一组候选基因在降低，增加，自然发生的变量时会产生可比较的表型的程度。为了解决这两个问题，我们提出了HIPSC技术在1）剖析液时突变如何改变关键途径的独特应用，然后2）测试单个遗传背景和鉴定危险因素如何易于使人类神经元和星形胶质细胞中的生物化学表型的易害。在可能的情况下，我们将将体外信息与有关个别患者的临床数据和UCSD ADRC的验证后病理联系起来。对SAD患者的HIPSC线的分析对于探测普通遗传危险因素如何在神经元和星形胶质细胞中起作用至关重要，并且还将对SAD患者的基因组频率和对照组进行初始估计，从而引起与神经元细胞中相关SAD表型的对照组，从而在体外分化了。此频率估计将有助于解决是否可以使用HIPSC线来预测给定个体会发展SAD的可能性，即产生预测性基因组/HIPSC诊断SAD的可能性。利用我们和其他人的先前工作，这些工作分析了携带APP重复或三体术的患者的HIPSC系列。这两种情况似乎都通过在否则的整倍体基因组中增加App表达增加了50％，从而引起了FAD。由这些HIPSC线制成的神经元暴露于典型的AD生化改变，包括升高A，GSK3的激活升高以及tau在拟议的病理部位升高Tau的临床化升高。我们还发现APPV717F而不是PS1DE9突变导致P-TAU水平升高。这就是APP和呈现蛋白突变的早期神经元表型可能不同，这可能会导致可能存在多种早期的致病途径，可以使用HIPSC技术研究。我们还发现，HIPSC研究可以阐明一种常见的遗传危险因素SORL1如何作用于人类神经元。因此，我们提出了三个具体目的：1）检验以下假设：App，ps1和 - 分泌酶突变触发了人类神经元和星形胶质细胞中相同的早期事件，从而导致AD典型的下游生化病理学。 2）检验以下假设：GWAS研究中鉴定为危险因素的基因会产生AD表型，并在过度或不渗透时会改变内吞，贩运或运输。 3）检验以下假设：GWAS研究中通过改变神经元或星形胶质细胞中的基因表达来鉴定出的常见遗传变异。