Molecular and Cellular Phenotype of Aging and iPS Cells

描述（由申请人提供）：诱导多能干细胞（iPS）是细胞替代疗法中供体群体衍生的新来源。然而，由于iPS细胞的主要应用涉及主要影响老年人的疾病，如心力衰竭、中风和神经退行性疾病，因此未来临床应用的大多数iPS细胞很可能将从老年患者的衰老和老年体细胞群中分离出来。目前尚不清楚衰老和衰老如何影响体细胞重编程的能力。衰老和衰老是否会影响诱导多能干细胞的后续分化及其诱导多能干细胞衍生物的效率也尚不清楚。这项NIH挑战拨款提案将解决这些问题。我们建议从老年（60 ~ 70岁）、中年（40 ~ 50岁）和新生儿（1 ~ 2周龄）患者的成纤维细胞中获得iPS细胞系。我们将评估衰老和衰老是否会损害iPS细胞的重编程效率、基因表达、多能性能力以及对氧化应激和DNA损伤的敏感性。我们将把来自所有年龄组患者的iPS细胞分化为功能性内皮细胞，并将这些细胞与来自人胚胎干细胞和人微血管内皮细胞（HMECs）的内皮细胞在体外和体内的功能进行比较。最后，我们将比较来自老年患者的iPS细胞与快速衰老的iPS细胞系，其中Sirtuin（沉默交配型信息调控2同源物）6（也称为SIRT6）基因已被敲除。总的来说，这些结果将为未来患者特异性iPS细胞疗法的临床翻译提供有价值的信息。

DESCRIPTION (provided by applicant): Induced pluripotent stem (iPS) cells are a novel source for derivation of donor populations in cell replacement therapy. However, because the major applications of iPS cells relate to diseases predominately affecting elderly populations such as heart failure, stroke, and neurodegenerative disease, it is likely that the majority of iPS cells derived for future clinical use will be isolated from senescent and aged somatic cell populations of elderly patients. Currently it is not known how aging and senescence affect the capacity of somatic cells to be reprogrammed. It is also not known whether aging and senescence affect the subsequent differentiation of iPS cells and the efficiency of their iPS cell derivatives. This NIH Challenge Grant proposal will address these questions. We propose to derive iPS cell lines from fibroblasts of elderly (>70 years old), middle-age (40-50 years old), and newborn (1-2 week old) patients. We will assess whether aging and senescence may impair reprogramming efficiency as well as gene expression, capacity for pluripotency, and sensitivity to oxidative stress and DNA damage in iPS cells. We will differentiate iPS cells derived from patients of all age groups into functional endothelial cells and compare the in vitro and in vivo functions of these cells with endothelial cells derived from human embryonic stem cells and human microvascular endothelial cells (HMECs). Finally, we will compare iPS cells derived from elderly patients with a rapidly aged line of iPS cells in which the Sirtuin (silent mating type information regulation 2 homolog) 6 (also known as SIRT6) gene has been knocked down. Collectively, these results will provide valuable information for future clinical translation of patient-specific iPS cell therapies. PUBLIC HEALTH RELEVANCE: Aging has been shown to impair the integrity, function, and proliferative capacity of many adult stem cells such as hematopoietic stem cells, muscle satellite cells, and cardiac progentior cells. We propose to analyze the effects of aging and senescence upon somatic cells that undergo cellular reprogramming into iPS cells. This study will provide valuable insight into the process of aging and yield useful information on how patient-specific pluripotent cells may be used in elderly patients suffering from such diseases as heart failure, stroke, and neurodegenerative disease.