Embryonic Stem Cell Derived Cardiac Myocytes

本研究领域涉及胚胎干细胞分化为心肌细胞之前和过程中的研究。在这些研究中，我们使用了胚胎干细胞（ES）细胞（R1, D3），胚胎生殖细胞（EG-1）和胚胎癌细胞（P19）。我们已经建立了一种最有效的体外胚胎干细胞生成心肌细胞的系统，并且我们已经确定了ryanodine受体、SR caatp酶、磷蛋白和二氢吡啶受体首次在体外分化中表达的时间，允许研究EC与分化的偶联。选择方案（最近使用Na/Ca交换启动子的心脏限制性部分）允许心肌细胞的分离。总的来说，这项研究旨在产生心脏谱系特异性细胞，以了解调节蛋白在体外心肌细胞形成中的作用。此外，如果细胞可以被分离到均匀性，并且在体外分化后显示出活力，那么我们建议使用这种技术来测试啮齿动物细胞基础治疗后的递送方案和心脏功能的改善。这项基础研究工作的一个主要焦点是致力于提高这些细胞在体外培养条件下的生存能力。干细胞中的几个靶基因也被修改，以确定它们在心肌细胞分化和存活中的作用，最近，我们已经开始分离（和靶向）细胞，以选择可能更适合细胞基础治疗的心脏祖细胞亚群。通过研究胚胎干细胞的基本生物学，我们希望能够描述心肌细胞发育和更新的机制，并将这些结果应用于改进可能适用于人类的细胞基础疗法。

SUMMARY OF WORK This research area involves the study of embryonic stem cells prior to and during differentiation to cardiomyocytes. For these studies, we employ embryonic stem (ES) cells (R1, D3), embryonic germ cells (EG-1) and embryonic carcinoma cells (P19). We have established one of the most efficient systems available for the generation of cardiomyocytes from ES cells in vitro, and we have established when the ryanodine receptor, SR CaATPase, phospholamban and dihydropyridine receptor were first expressed with in vitro differentiation, permitting studies of EC coupling with differentiation. Selection protocols (most recently with a cardiac-restricted portion of the Na/Ca exchanger promoter) have permitted the isolation of cardiomyocytes. Overall, the research is aimed at generating cardiac-lineage specific cells to understand the role of regulatory proteins in the formation of cardiomyocytes in vitro. Additionally, if the cells can be isolated to homogeneity and shown to be viable after in vitro differentation, then we propose using this technique to test delivery protocols and improvements of cardiac function following cellular based therapies in rodent. A major focus of this basic research effort is devoted to the improved viability of these cells during in vitro cultivation conditions. Several target genes are also being modified in the stem cells to determine their role in cardiomyocyte differentiation and survival, and more recently, we have begun isolating (and targeting) cells to select sub-populations of cardiac progenitor cells that may be more appropriate for cellular based therapies. By studying the basic biology of embryonic stem cells, we hope to delineate mechanisms responsible for cardiomyocyte development and renewal, and apply these results to improve cellular based therapies that may be applicable to man.