Functional Vascular Progenitors from Naive Human iPSC

描述（由申请人提供）：用于儿科和成人缺血性疾病（如脑血管性中风、镰状细胞病和糖尿病视网膜病变）的幼稚人iPSC干细胞治疗的功能性血管祖细胞最终不仅需要受损心肌、脑、造血和视网膜组织的再生，而且还需要重建引发初始疾病开始的缺陷血管生态位。人类血管系统通常来自于高增殖的胚胎成血管细胞或血管祖细胞（VP），它们在早期发育过程中分化为血管内皮细胞和周细胞。这种多产的胚胎样VP在成人中是罕见或不存在的。此外，尽管已提出循环成体内皮祖细胞（EPC）用于血管细胞疗法，但此类EPC不仅限于多能性和扩增，而且在疾病如糖尿病中功能缺陷。如果缺血性脱细胞毛细血管可以用自体或HLA匹配的胚胎血管/周细胞祖细胞有效修复，则终末期血管疾病如糖尿病和心脏缺血可以逆转。一种解决方案是将人诱导多能干细胞（hiPSC）分化成VP，其具有用于再生患病组织的高度多产的胚胎样内皮-间充质-周细胞潜能。然而，这一目标目前受到效率低下和可变性的限制， 从hiPSC定向血管分化。有必要首先通过更安全的非整合、非病毒衍生方法产生高质量的临床级hiPSC。在这个项目中，我们将通过有效地将患者自身的血细胞重新编程为一种新的高质量的多能性状态来实现这一目标，这种状态被称为“幼稚基态”，类似于小鼠胚胎干细胞（ESC）。与传统的人类ESC和hiPSC相比，幼稚的人类iPSC（N-hiPSC）具有更多功能，包括在培养中更快速的扩增，更大的分化潜能，以及通过基于质粒的同源重组进行基因靶向遗传操作的更高能力。我们将产生和分化N-hiPSC，并专门测试它们进行基因靶向和产生功能性胚胎VP的能力，这些功能性胚胎VP在功能上整合到缺血组织中，用于未来的细胞治疗。最后，我们将对幼稚和常规hiPSC及其分化的VP后代进行详细的比较表观遗传学分析，以阐明差异CpG甲基化和组蛋白结构。我们建议，患者特异性的幼稚hiPSC最终将为儿科和成人再生医学的细胞和基因治疗提供更大的通用性。

DESCRIPTION (provided by applicant): Functional Vascular Progenitors from Na�ve Human iPSC Stem cell treatments for pediatric and adult ischemic disorders such as cerebro-vascular stroke, sickle cell disease, and diabetic retinopathy ultimately require not only the regeneration of damaged myocardium, brain, hematopoietic, and retinal tissues, but also the reconstruction of the defective vascular niche that instigated the initial disease to begin with. The human vasculature normally arises from highly prolific embryonic angioblasts or vascular progenitors (VP) that differentiate into vascular endothelial cells and pericytes during early development. Such prolific embryo-like VP are rare or non-existent in the adult. Furthermore, although circulating adult endothelial progenitor cells (EPC) have been proposed for vascular cellular therapies, such EPC are not only limited in multipotency and expansion, but also functionally defective in diseases such as diabetes. If ischemic acellular capillaries could be efficiently repaired with autologous or HLA- matched embryonic vascular/pericytic progenitors, end stage vascular diseases such as diabetes and cardiac ischemia could be reversed. One solution would be to differentiate human induced pluripotent stem cells (hiPSC) into VP that possess highly prolific embryo-like endothelial- mesenchymal-pericytic potential for regenerating diseased tissues. However, this goal is currently limited by the poor efficiency and variability of directed vascular differentiation from hiPSC. It will be necessary to first generate high-quality clinical grade hiPSC via safer non-integrating, nonviral derivation methods. In this project, we will accomplish this goal by efficiently reprogramming a patient's own blood cells to a novel high quality state of pluripotency called the "na�ve ground state" that resembles mouse embryonic stem cells (ESC). Na�ve human iPSC (N-hiPSC) possess more versatile abilities than conventional human ESC and hiPSC including more rapid expansion in culture, greater differentiation potencies, and a higher capacity to be genetically manipulated by gene targeting with plasmid-based homologous recombination. We will generate and differentiate N-hiPSC, and specifically test for their capacity to undergo gene targeting and to produce functional embryonic VP that functionally integrate into ischemic tissues for future cell therapies. Finally, we will conduct detailed comparative epigenetic analyses of na�ve and conventional hiPSC and their differentiated VP progeny to elucidate differential CpG methylation and histone architectures. We propose that patient-specific na�ve hiPSC will ultimately provide greater versatility for cellular and gene therapies for pediatric and adult regenerative medicine.