Novel Stem Cell and Mouse Models to Study Frontotemporal Dementia

描述(申请人提供)：几种脑部疾病是由蛋白质聚集引起的；仅额颞叶痴呆(FTD)和阿尔茨海默病就影响了近500万美国人。虽然老鼠是疾病的模型，但它们可能在几个月甚至几年内都不会生病。取而代之的是，来自这些小鼠的细胞培养系统可能在几天或几周内提供关于疾病机制的信息，从而加速疾病治疗的发现。总体假设是，产生携带导致疾病的基因突变或组合的干细胞系将为研究发病机制提供宝贵的研究工具。具体地说，含有神经球的中枢神经系统干细胞将在体外研究它们在重现亲本鼠品系表型方面的有效性。微管相关蛋白tau基因突变的小鼠准确地模拟了人类FTD的生化、组织学和行为方面。疾病的突出细胞表型，tau蛋白的过度磷酸化和聚集，可以用传统的蛋白质检测方法进行追踪，并将被用作评估神经球及其分化后代作为模型的实用性的标记。目标1的重点是确定神经球是否表现出与其亲本株中观察到的tau病理相同的突变特异性时间序列，并调查转基因表达如何影响增殖、存活和分化。结果将与表达人类编码的野生型tau基因的神经球和小鼠进行比较。由tau磷酸化事件引起的小鼠模型疾病的一个陷阱是，内源性小鼠tau可能抑制人类编码的tau磷酸化。因此，目标2的重点是在体内和体外检验内源性小鼠tau基因的表达改变人类转基因编码的tau蛋白磷酸化和聚集的假说。突变型和野生型人类tau转基因都将被转移到小鼠tau缺失的背景中。将对小鼠和神经球进行表征，并与相应的小鼠tau野生型品系进行比较。如果神经球在体内概括了其亲代小鼠品系的表型，它们可能会作为高通量分析系统来研究参与疾病发病机制的其他基因和小分子。

DESCRIPTION (provided by applicant): Several brain diseases arise from protein aggregation; fronto-temporal dementia (FTD) and Alzheimer's disease alone affect nearly 5 million Americans. Though mice model aspects of disease, they may not become ill for months or even years. Instead, cell culture systems derived from these mice may provide information about disease mechanisms in days or weeks thereby speeding discovery of disease treatment. The overall hypothesis is that generating stem cell lines carrying mutations or combinations of genes leading to diseases will provide valuable research tools to study pathogenesis. Specifically, central nervous system stem cell containing neurospheres will be investigated for their efficacy in recapitulating parent mouse strain phenotypes in vitro. Mice with mutations in the microtubule associated protein tau gene accurately model biochemical, histological, and behavioral aspects of human FTD. Prominent cellular phenotypes of disease, hyperphosphorylation and aggregation of the tau protein, can be tracked with conventional protein detection methods and will be used as markers to assess the utility of neurospheres and their differentiated progeny as models. The focus of Aim 1 is to determine if neurospheres exhibit the same mutation-specific temporal sequence of tau pathology observed in their parental strains, and investigate how proliferation, survival, and differentiation are affected by transgene expression. Results will be compared to neurospheres and mice expressing the human encoded wild type tau gene. One pitfall to mouse modeled diseases arising from tau phosphorylation events is that endogenous mouse tau may inhibit human encoded tau phosphorylation. Therefore the focus of Aim 2 is to test the hypothesis that expression of endogenous mouse tau alters human transgene-encoded tau phosphorylation and aggregation in vivo and in vitro. Both mutant and wild type human tau transgenes will be transferred to a mouse tau null background. Mice and neurospheres will be characterized and compared to corresponding mouse tau wild type lines. If neurospheres recapitulate in vivo phenotypes of their parent mouse strains, they may serve as high through-put assay systems to investigate other genes and small molecules involved in disease pathogenesis.