Epigenetic strategies for the in vitro generation of replacement beta cells

描述(由申请人提供)：这项建议的总体目标是开发从人类胚胎干细胞(HES)或患者来源的诱导多能干细胞(IPS)中获得葡萄糖反应性胰岛素产生细胞的策略。基于这一目标，我们的提案将推进NIH-NIDDK Beta细胞生物学联盟的重点领域之一，即“利用胰腺发育的线索直接从干细胞/祖细胞中分离出用于糖尿病细胞替代疗法的细胞”。为了实现我们的目标，我们组建了一个由五名研究人员组成的联盟，其中包括(细胞和干细胞生物学以及基因组学方面的专家)。通过对各种原始胚胎和成人细胞和组织中关键的组蛋白修饰的全基因组作图，我们将定义定义胰腺祖细胞及其内分泌后代的表观遗传学特征。这些知识将被用来指导改进HES细胞的体外分化方案，使其分化为胰岛前体细胞，并最终转化为葡萄糖反应性胰岛素产生的P细胞。我们建议的关键是一种新的细胞微阵列技术，该技术允许组合筛选细胞外基质成分、因子和/或分子通路，以支持从HES细胞到成熟(-细胞)的逐步分化路径上有效地产生每个中间前体。表观遗传学特征将被用作终点，以评估体外产生的HES细胞来源的细胞与体内胰腺对应细胞的相似程度。在移植到糖尿病小鼠模型后，HES细胞来源的(-细胞)最终将接受测试，以确定它们纠正血糖升高的能力。 公共卫生相关性：自从胰岛移植的第一个开创性工作以来，基于细胞的糖尿病治疗方法在胰岛素独立性和降低低血糖风险方面可以有显著的好处，这一点已经变得明显。通过探索从人类胚胎干细胞中提取产生胰岛素的β细胞用于细胞移植的新起点，该提案寻求开发糖尿病的细胞疗法。

DESCRIPTION (provided by applicant): The overall objective of this proposal is to develop strategies for deriving glucose-responsive insulin-producing (-cells from human embryonic stem (hES) cells or patient-derived induced pluripotent stem (iPS) cells. With this objective our proposal will advance one of the focus areas of the NIH-NIDDK Beta Cell Biology Consortium, which is "to use cues from pancreatic development to directly differentiate (-cells from stem/progenitor cells for use in cell-replacement therapies for diabetes". To achieve our objectives we have assembled a consortium of five investigators, which includes experts in (-cell and stem cell biology as well as genomics. By genome-wide mapping of key histone modifications in a variety of primary embryonic and adult human cells and tissues, we will define epigenetic signatures that define pancreatic progenitors and their endocrine descendants. This knowledge will be used to guide efforts for improving preexisting in vitro differentiation protocols of hES cells into pancreatic progenitors and eventually glucose-responsive insulin-producing p-cells. Key to our proposal is a novel cellular microarray technology that allows for combinatorial screening of extracellular matrix components, factors and/or molecular pathways for their ability to support efficient generation of each intermediary precursor along the step-wise differentiation path from hES cell to mature (-cell. The epigenetic signatures will be used as endpoints to assess how closely the in vitro-generated, hES cell-derived cells resemble their in vivo pancreatic counterparts. hES cell-derived (-cells will eventually be tested for their ability to correct elevated blood glucose levels upon transplantation into diabetic mouse models. PUBLIC HEALTH RELEVANCE: Since the first pioneering work on islet transplantation, it has become clear that a cell-based approach for the treatment of diabetes mellitus can have significant benefits in terms of insulin independence and a reduced risk of hypoglycemia. By exploring novel startegies for deriving insulin-producing beta-cells from human embryonic stem cells for cell transplantation, this proposal seeks to develop cell therapies for diabetes.