Induced pluripotent stem cells: New advances in cardiac regenerative medicine

To bring the notion of cardiac regenerative medicine to fruition, researchers have tried to determine which stem cells, embryonic stem (ES) cells or somatic stem cells, are most suitable. Thus far, there is no clear indication which is better, because both have their own advantages and disadvantages. In 2006, murine induced pluripotent stem (iPS) cells were first established. Since then, basic research into the properties of iPS cells has continued apace. Originally, human iPS cells were generated from dermal fibroblasts by retrovirus-mediated gene transfer. Although this technique is sophisticated and easy to perform, the skin biopsy is accompanied by some bleeding and pain, and there may be some damage to the host genome because of retrovirus-mediated transgene integration. However, methods of producing iPS cells have improved steadily. For clinical application in the cardiovascular field, efficient methods that produce pluripotent stem cells that can differentiate into cardiomyocytes need to be developed. Existing methods for ES cells can be applied to iPS cells to obtain cardiomyocyte differentiation. In addition, existing purification methods can be used to obtain pure cardiomyocytes from a population of mixed cells. These techniques have themselves been the subject of extensive research, and continued advances are now making the clinical application of pluripotent stem cells a reality. We are at the forefront of medical innovations in the cardiovascular field based on the use of pluripotent stem cells.