Can Somatic Stem Cells Regenerate Myocardial Tissue

Somatic stem cells can be obtained from various sources and their differentiation potential is not restricted only to the differentiated cell phenotypes of the source tissue. Therefore, somatic stem cells offer a great promise for cell replacement therapy in diseased hearts. Yet, much confusion has been created concerning the use of somatic stem cells. Different methods have been used to isolate and recognize stem cells, and the nomenclature is not standardized and often based on the method of cell isolation, making it difficult to compare the different studies. In humans the situation is worse as the scientific approach to the stem cell issue is overtaken by clinical applications of somatic stem cells or approaches to mobilize endogenous stem cells. Here we discuss the current knowledge on somatic stem cells in animalmodels and humans. In addition, the solid proof for beneficial effects of stem cell mobilization is critically reviewed and finally the question whether cardiomyoblasts exist is addressed. This chapter is written to provide clarity on different classifications of somatic stem cells and to raise hypothesis for future research.