Probing SORL1 Risk Factors with Human Induced Pluripotent Stem Cell Technology

利用人类诱导多能干细胞技术探索 SORL1 危险因素

• 批准号: 8676147
• 负责人: Lawrence S. Goldstein
• 金额: $ 15.75万
• 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: 2014-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8676147
• 关键词: Alzheimer' s Disease; Alzheimer' s disease model; Amyloid beta-Protein; Autopsy; Behavior; Biochemical; Brain-Derived Neurotrophic Factor; Candidate Disease Gene; Cell Line; Cerebrospinal Fluid; Clinical; Clinical Data; Clinical Trials; Collection; Complex; Data; Development; Disease; Family; Future; Gene Expression; Gene Proteins; Generations; Genes; Genetic; Genetic Status; Genome; Genotype; Goals; Haplotypes; Heritability; Human; In Vitro; Individual; Lead; Learning; Lesion; Life; Link; Measures; Modeling; Monitor; Neurons; Oxygen; Pathogenesis; Pathology; Pathway interactions; Patients; Peptides; Phenotype; Phosphotransferases; Play; Regulation; Regulator Genes; Relative (related person); Research; Risk; Risk Factors; Role; Signal Transduction; Stratification; TNFRSF5 gene; Testing; Transgenic Animals; Variant; Work; amyloid precursor protein processing; base; biological adaptation to stress; comparative; coping; drug discovery; effective therapy; genetic risk factor; genetic variant; human disease; human tissue; in vivo; induced pluripotent stem cell; mouse model; neurofibrillary tangle formation; neuropathology; patient population; receptor; research study; response; risk variant; sortilin; stem cell technology; tau Proteins

PROJECT 1: ABSTRACT. A key problem in understanding and eventually treating Alzheimer's disease (AD) is our incomplete understanding of the role of genetic risk factors in late-onset, sporadic AD (SAD). While there is no clear single genetic lesion that causes SAD, the observed high heritability suggests that individual genetic background plays a significant role. Here we propose unique applications of human induced pluripotent stem cell (hIPSC) technology to dissect how individual genetic background and identified risk factors predispose to SAD biochemical phenotypes in human neurons and to link that information to clinical data on individual patients and to post-mortem pathology. We are basing our work on our recent finding using hIPSC technology that tested the hypothesis that R haplotypes cause general reduction of SORL1 expression leading to increased amyloid beta (Aß) peptides and consequent risk of developing SAD [3, 7- 10]. Using hIPSC technology we found that R haplotypes impair a signaling input to the SORL1 gene. Specifically, P haplotypes respond to BDNF by inducing SORL1 expression, while R haplotypes do not. Basal expression levels show no correlation with R or P haplotypes. Thus, the SORL1 genetic contribution to SAD may be caused by complex regulatory variation in living human neurons. We now propose to test our working model for how SORL1 haplotypes contribute to SAD neuronal phenotypes and thus SAD risk in humans in vitro, and in vivo in human patients. We propose to test: 1) the hypothesis that BDNF-induced SORL1 expression modulates amyloidogenic processing of APP and downstream SAD-associated biochemical changes; and 2) the hypothesis that effects of SORL1 haplotype on neuronal phenotypes in vitro are mirrored in clinical data on SAD patients, specifically the relative amounts of BDNF and SORL1 proteins in cerebrospinal fluid (CSF) and post-mortem neuropathological phenotypes. In a related goal, we will investigate whether purified neurons made from our collection of patient hIPSC lines correlates with clinical behavior of individual patients. At present, we have too few hIPSC lines to definitively establish the degree of correlation rigorously, but given the existence of the lines, we will begin to collect comparative data as a way of contributing to future studies. Together, these experiments will provide new data about the details of SORL1 variant contributions to SAD phenotypes in human neurons with differing genetic backgrounds and potentially lead to new pathways for drug discovery and stratification of clinical trials based on genetic background. Our specific aims are to: 1. Test the hypothesis that the reduced BDNF induction response of purified human neurons with SORL1 risk variant haplotypes enhances SORL1- dependent downstream biochemical SAD phenotypes. 2. To test the hypothesis that the genetic status of patients at the SORL1 locus has a significant influence on clinical phenotypic markers measured in CSF or by post-mortem pathology.

项目1：摘要。 我们的不完整是理解甚至有时治疗阿尔茨海默氏病（AD）的关键问题 了解遗传危险因素在晚期，零星AD（SAD）中的作用。虽然没有清楚的 引起悲伤的单个遗传病变，观察到的高遗传力表明个体遗传 背景起着重要作用。在这里，我们提出了人类诱导多能的独特应用 干细胞（HIPSC）技术，以剖析单个遗传背景和确定风险因素的方式 易感人类神经元中的生化表型，并将这些信息与临床数据联系起来 个体患者和验尸后病理学。我们的工作是基于我们最近的发现 HIPSC技术测试了R单倍型导致SORL1的普遍减少的假设 表达导致淀粉样蛋白β（Aß）肽的增加，并导致发展SAD的风险[3，7-- 10]。使用HIPSC技术，我们发现R单倍型会损害SORL1基因的信号输入。 具体而言，P单倍型通过诱导的SORL1表达对BDNF做出反应，而R单倍型则没有。 基础表达水平与R或P单倍型无关。那，sorl1遗传贡献 可悲的是，生命的人类神经元中复杂的调节变化可能引起。我们现在建议测试 我们有关Sorl1单倍型如何促进SAD神经元表型的工作模型，从而在 人类在体外和人体患者的体内。我们建议测试：1）BDNF诱导的假设 SORL1表达调节APP的淀粉样蛋白生成处理和下游SAD相关 生化变化； 2）SORL1单倍型对神经元表型的影响的假设 体外反映在SAD患者的临床数据中，特别是BDNF和SORL1的相对量 脑脊液（CSF）和验尸神经病理表型中的蛋白质。在相关目标中，我们 将研究我们的患者HIPSC系列收集的纯化神经元是否与 个别患者的临床行为。目前，我们的HIPSC线太少，无法确定 严格的相关程度，但是鉴于线条的存在，我们将开始收集比较 数据是为未来研究做出贡献的一种方式。这些实验将共同提供有关 SORL1变体对具有区分遗传的人神经元中SAD表型的贡献的细节 背景和潜在地导致了临床试验的药物发现和分层的新途径 基于遗传背景。我们的具体目的是：1。检验降低BDNF的假设 纯化的人神经元具有SORL1风险变异单倍型的诱导反应增强了SORL1- 依赖的下游生化SAD表型。 2。检验以下假设 Sorl1基因座的患者对CSF或CSF或 验尸病理学。