Modeling Inherited Neurodevelopmental Disorders with Human Induced Pluripotent Stem Cells

项目摘要 由于许多原因，神经发育障碍的发病机制具有挑战性。人类 大脑相对难以直接评估，人体尸检和成像研究提供的信息有限， 研究分子或细胞机制的机会，动物模型有时不复制重要的 疾病特征，并且永生化神经元样细胞系不能用于模拟正常发育。诱导 多能干细胞（iPSC）为解决这些局限性提供了一种强有力的新实验工具。他们可以 从患有由定义的突变引起的已知发育障碍的患者中创建，它们提供了 可再生资源，并且它们可以分化成特定的细胞谱系，以提供物种特异性和 谱系特异性实验模型，以研究细胞和分子水平的发育机制。 在当前的提案中，我们解决了与iPSC建模广泛相关的几个基本问题 治疗神经发育障碍我们将Lesch-Nyhan病（LND）作为一种原型疾病，因为 它具有许多特征，使其成为用于iPSC建模的异常易处理的孟德尔病症。LND和 其较温和的变异是由HPRT 1基因突变引起的，导致嘌呤补救缺乏， 酶，次黄嘌呤鸟嘌呤磷酸核糖转移酶（HGprt）。神经行为异常 这种疾病与大脑多巴胺神经元的发育功能障碍有关。目标1侧重于 在疾病严重程度的范围内建立一个特征良好的iPSC库，以解决问题 与导致不同疾病严重程度的特定突变如何反映在iPSC模型中有关。目标2重点 建立一个特征良好的同基因iPSC库，其中引入了特定的突变， 通过基因编辑方法，解决与产生iPSC的个体的遗传背景相关的问题。 模型是派生的。在Aim 3中，我们将这些细胞系分化为多巴胺神经元，以解决iPSC模型 可揭示LND发病的时间和机制。总的来说，该项目将解决 与神经发育障碍的iPSC建模广泛相关的基本问题，以及 对LND神经行为异常的发病机制有更具体的了解。

PROJECT SUMMARY The pathogenesis of neurodevelopmental disorders is challenging to address for many reasons. The human brain is relatively inaccessible for direct evaluation, human autopsy and imaging studies provide limited opportunities to study molecular or cellular mechanisms, animal models sometimes do not replicate important disease features, and immortalized neuron-like cell lines cannot be used to model normal development. Induced pluripotent stem cells (iPSCs) provide a powerful new experimental tool to address these limitations. They can be created from patients with known developmental disorders caused by defined mutations, they provide a renewable resource, and they can be differentiated into specific cell lineages to provide species-specific and lineage-specific experimental models to study developmental mechanisms at the cellular and molecular levels. In the current proposal we address several fundamental questions that are broadly relevant to iPSC modeling for neurodevelopmental disorders. We focus on Lesch-Nyhan disease (LND) as a prototype disorder, because it has numerous features that make it an unusually tractable Mendelian disorder for iPSC modeling. LND and its milder variants are caused by mutations in the HPRT1 gene, resulting in deficiency of the purine salvage enzyme, hypoxanthine-guanine phosphoribosyltransferase (HGprt). The neurobehavioral abnormalities in this disorder have been linked with developmental dysfunction of brain dopamine neurons. Aim 1 focuses on establishing a well-characterized bank of iPSCs across the spectrum of disease severity, to address issues related to how specific mutations causing different disease severity are reflected in iPSC models. Aim 2 focuses on establishing a well-characterized bank of isogenic iPSCs in which specific mutations have been introduced via gene editing methods, to address issues related to the genetic background of individuals from which iPSC models are derived. In Aim 3 we differentiate these lines into dopamine neurons, to address how iPSC models can reveal the timing and mechanisms of pathogenesis related to LND. Overall, this project will address fundamental questions that are broadly relevant for iPSC modeling of neurodevelopmental disorders, as well as more specific insights into the pathogenesis of the neurobehavioral abnormalities of LND.