Prospective identification of cardiac progenitors by a novel single cell-based cardiomyocyte induction

SPECIFIC AIMSThe goal of the present study is the elucidation of cardiomyocyte differentiation mechanisms and exploration of novel cardiac regeneration strategies. We have developed a novel in vitro cardiomyocyte differentiation system using embryonic stem (ES) cells that enables reproduction of cellular process of cardiomyocyte differentiation in vitro and the dissection of the cellular and molecular mechanisms of cardiomyocyte differentiation at the single cell level.PRINCIPAL FINDINGS1. Induction and purification of cardiomyocytes from Flk1+ mesoderm cells on 2-D cultureEarlier we established an ES cell differentiation system for blood vessels in a 2-dimensional (2-D) culture devoid of embryoid body (EB) formation that reproduces early vascular development from progenitor cells expressing Flk1, a vascular endothelial growth factor receptor. In this study, we induced cardiomyocytes from Flk1+ mesoderm cells on 2-D culture. Flk1+ cells were induced and purified using an ES cell line carrying α-myosin hea...