ABSTRACT
Recent advances in stem cell biology, such as generation of induced pluripotent stem cells (iPS cells) (Takahashi et al. 2007; Yu et al. 2007) and embryonic stem cells (ES cells) (Thomson et al. 2007), has progressed to the feasibility of induction of cardiac differentiation from these cell sources. Since these important breakthroughs, a substantial numbers of studies have been conducted to explore the possibility of cardiac regeneration therapy to treat incurable heart diseases using stem cell derived cardiac cells. Most of the studies have been attempted by local injection of stem cell derived cardiomyocytes into diseased hearts; however, the functional outcomes were not necessarily as good as expected. These discouraging results have been attributed, at least in part, to low survival rate or hampered function of the transplanted cells in vivo. These fi ndings suggest that simple injection of isolated cells can only yield aggregation of cells with the loss of extracellular matrix and cell-to-cell connections that play an important role in maintaining survival and function of cells.
