Characterization of Islet1+ Progenitors Derived from Human Embryonic Stem Cells

来自出生后和胚胎心脏的多能Isl 1+心血管前体细胞（MICPs）具有分化成心脏发生所需的关键细胞谱系的能力：心肌细胞、平滑肌细胞和内皮细胞。它们在成人心脏中的鉴定对心脏恢复功能具有巨大的意义，但在分子水平上对这些祖细胞以及它们是如何被激活的知之甚少。 指定的.我们最近开发了一种方法，使人胚胎干细胞（hESC）可以均匀分化为Isl1+祖细胞在化学成分确定的培养基。这是一个很好的机会，可以彻底了解Isl1+祖细胞的基本生物学，也许可以将它们开发为最终可用于心血管细胞治疗和组织工程的潜在细胞来源。 这项建议将： 1.表征hESC衍生的Isl 1+祖细胞特化所需的信号传导途径。由于本规范需要WntSa和BMP 4，因此将特别强调它们在Isl1+祖细胞生成中的作用。 2.建立Isl 1+祖细胞维持和扩增的条件。这将涉及研究Isl 1+状态的分子基础的实验，包括信号通路的分析 和对Isl1+祖细胞发育重要的下游转录因子网络。 3.建立hESC衍生的Isl 1+祖细胞的分化能力，假设它们具有产生心肌细胞、平滑肌细胞和内皮细胞的潜力。与此同时， 将评价Isl 1+祖细胞在心脏和后肢缺血的动物模型系统中的功能。 我们已经开发的用于产生Isl1+祖细胞的统一的、稳健的方法有可能显着推进我们对与心脏发育相关的早期胚胎事件的理解，以及开发与心血管疾病相关的细胞疗法。

Multipotent Isl1+ cardiovascular precursors (MICPs) derived from post-natal and embryonic hearts have the capacity to differentiate into the critical cell lineages required for cardiogenesis: cardiomyocytes, smooth muscle and endothelial cells. Their identification in the adult heart has enormous implications for cardiac restorative function but little is known about these progenitors at the molecular level and how they are specified. We have recently developed a method whereby human embryonic stem cells (hESCs) can be uniformly differentiated into Isl1+ progenitors in chemically defined media. This represents an excellent opportunity to thoroughly understand the basic biology of Isl1+ progenitors and perhaps, to develop them as a potential source of cells that could eventually be used for cardiovascular cell therapies and tissue engineering. This proposal will: 1. characterize signaling pathways required for specification of hESC-derived Isl1+ progenitors. Since WntSa and BMP4 are required for this specification, special emphasis will be placed on their role in the generation of Isl1+ progenitors. 2. establish conditions for maintenance and amplification of Isl1+ progenitors. This will involve experiments where the molecular basis underpinning the Isl1+ state is investigated including analysis of signaling pathways and downstream transcription factor networks important for Isl1+ progenitor development. 3. establish the differentiation capacity of hESC-derived Isl1+ progenitors with the hypothesis that they have the potential to generate cardiomyocytes, smooth muscle cells and endothelial cells. In parallel, the ability of Isl1+ progenitors to function in animal model systems for cardiac and hind limb ischemia will be evaluated. The uniform, robust method for generation of Isl1+ progenitors that we have developed has the potential to significantly advance our understanding of early embryonic events associated with cardiac development and, for the development of cell therapeutics associated with cardiovascular disease.