Differentiation of human embryonic stem cells to cardiomyocytes for in vitro and in vivo applications.

The ability of human embryonic stem cells to differentiate into spontaneously contracting cardiomyocyte-like cells has attracted substantial interest from the scientific community over the last decade. From having been difficult to control, human cardiomyogenesis in vitro is now becoming a process which, to a certain extent, can be effectively manipulated and directed. Although much research remains, new and improved protocols for guiding pluripotent stem cells to the cardiomyocyte lineage are accumulating in the scientific literature. However, the stem cell derived cardiomyocytes described to date, generally resemble immature embryonic/fetal cardiomyocytes, and they are in some functional and structural aspects different from adult cardiomyocytes. Thus, a future challenge will be to design strategies that eventually may allow the cells to reach a higher degree of maturation in vitro. Nevertheless, the cells which can be prepared using current protocols still have wide spread utility, and they have begun to find their way into the drug discovery platforms used in the pharmaceutical industry. In addition, stem cell derived cardiomyocytes and cardiac progenitors are anticipated to have a tremendous impact on how heart disease will be treated in the future. Here, we will discuss recent strategies for the generation of cardiomyocytes from human embryonic stem cells and recapitulate their features, as well as highlight some in vitro applications for the cells. Finally, opportunities in the area of cardiac regenerative medicine will be illustrated.