Endoderm Induction and Pancreatic Specification from ES*

描述（由申请人提供）： 从培养的胚胎干（ES）细胞产生多种细胞类型的能力提供了前所未有的机会来研究调节导致初级胚层（外胚层、中胚层和内胚层）发育的谱系定型的最早阶段的机制。此外，胚胎干细胞提供了一种新的和潜在的无限供应的细胞移植治疗广泛的疾病。为了充分实现ES细胞系统的基本生物学和治疗潜力，必须首先确定在该模型中调节谱系诱导和组织特异性的机制。本研究的目的是探讨在小鼠和人ES细胞分化培养中调节内胚层诱导和胰腺特化的机制。总的办法是将前三个目标的每一个目标的实验集中在三个具体的发展阶段。在第一个目标中，我们将使用具有靶向短尾基因座的GFP cDNA和靶向Foxa 2（HNF 3（）基因座的人CD 4的小鼠ES细胞系来定义发育最早阶段所需的信号传导途径，建立原始条纹样群体。诱导与原条相当的种群代表了定形内胚层发育的第一步。第二个目标的重点是确定哪些因素调节内胚层和Pdx 1+胰腺祖细胞从原始条纹样细胞的发展。第三个目标是确定Pdx 1+祖细胞成熟为功能性胰岛素分泌细胞所需的条件。在第四个目标中，我们将把小鼠ES细胞的研究结果转化到人类系统中。与用于小鼠ES细胞分化的方法相当的方法将用于建立从人ES细胞发育原始条纹样细胞、内胚层、胰腺祖细胞和胰岛素分泌细胞所必需的条件。对于这些实验，我们将使用以下人ES细胞系：ES 02、ES 03、ES 04、TE-03、TE-06、MI 01、UC 01、WA 01、WA 07、WA 09、BG 02和BG 03。这些实验结果将为ES细胞分化模型中内胚层诱导和胰腺特化的调控提供新的见解

DESCRIPTION (provided by applicant): The ability to generate multiple cell types from embryonic stem (ES) cell in culture offers unprecedented opportunities to investigate the mechanisms that regulate the earliest stages of lineage commitment that lead to the development of the primary germ layers; ectoderm, mesoderm and endoderm. In addition, ES cells offer a novel and potentially unlimited supply of cells for transplantation for the treatment of a broad range of diseases. For the basic biological and therapeutic potential of the ES cell system to be fully realized, it is essential to first define the mechanisms that regulate lineage induction and tissue specification in this model. The goal of this proposal is to investigate the mechanisms that regulate endoderm induction and pancreatic specification in both mouse and human ES cell differentiation cultures. The overall approach is to focus the experiments in each of the first three aims on three specific stages of development. In the first aim, we will use a mouse ES cell line with the GFP cDNA targeted to the brachyury locus and human CD4 targeted to the Foxa2 (HNF3() locus to define the signaling pathways required for the earliest stage of development, the establishment of a primitive streak-like population. Induction of a population comparable to the primitive streak represents the first step in the development of definitive endoderm. The focus of the second aim is to determine what factors regulate the development of endoderm and Pdx1+ pancreatic progenitors from the primitive streak-like cells. The third aim will define the conditions necessary for the maturation of Pdx1+ progenitors to functional insulin secreting cells. In the fourth aim, we will translate the findings from the studies with mouse ES cells to the human system. Approaches comparable to those used for differentiation of the mouse ES cells will be used to establish conditions necessary for the development of primitive streak-like cells, endoderm, pancreatic progenitors and insulin-secreting cells from human ES cells. For these experiments we will use the following human ES cell lines: ES02, ES03, ES04, TE-03, TE-06, MI01, UC01, WA01, WA07, WA09, BG02 and BG03. The outcome of these experiments will provide new insights into the regulation of endoderm induction and pancreatic specification in the ES cell differentiation model