Modeling Inherited Neurodevelopmental Disorders with Human Induced Pluripotent Stem Cells

项目总结 由于许多原因，神经发育障碍的发病机制是具有挑战性的。人类 大脑相对难以获得直接评估，人类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，动物模型有时不能复制重要的 疾病特征和永生化的神经元样细胞系不能用来模拟正常发育。诱导式 多能干细胞(IPSCs)为解决这些局限性提供了一种强大的新实验工具。他们可以 是由已知由特定突变引起的发育障碍的患者创造出来的，它们提供了一种 可再生资源，它们可以分化成特定的细胞谱系，提供物种特有的和 在细胞和分子水平上研究发育机制的特定谱系实验模型。 在当前的提案中，我们解决了几个与IPSC建模广泛相关的基本问题 治疗神经发育障碍。我们把Lesch-Nyhan病(LND)作为一种典型疾病，因为 它有许多功能，使其成为IPSC建模中异常容易处理的孟德尔障碍。LND和 其较温和的变种是由HPRT1基因突变引起的，导致嘌呤回收不足 次黄嘌呤-鸟嘌呤磷酸核糖转移酶(HGprt)。其中的神经行为异常 障碍与大脑多巴胺神经元的发育障碍有关。目标1侧重于 建立一个涵盖各种疾病严重程度的IPSCs库，以解决各种问题 与导致不同疾病严重程度的特定突变如何在IPSC模型中反映有关。目标2重点 关于建立已引入特定突变的特性良好的等基因IPSCs文库的研究 通过基因编辑方法，解决与来自IPSC的个人的遗传背景有关的问题 对模型进行了推导。在目标3中，我们将这些线区分为多巴胺神经元，以解决如何建立IPSC模型 可以揭示与LND相关的发病时机和发病机制。总体而言，该项目将解决 与IPSC神经发育障碍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见解。

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.