Editorial [Hot Topic: Cardiac Cell Therapy: anno 2011 (Executive Guest Editor: Sophie Van Linthout)

During the last 15 years, three pioneer discoveries have changed our common understanding on vascular regeneration, cardiac repair, and cell re-differentiation/programming. In 1997, Asahara et al. [1] discovered the so called “endothelial progenitor cells”. This finding changed the paradigm that during postnatal life vascular remodeling and regeneration exclusively occurs through proliferation and subsequent migration of mature endothelial cells derived from pre-existing vessel walls (angiogenesis). In 2003, Quaini et al. [2] provided the first unequivocal documentation of the existence of primitive cells able to generate all the different component structures of the myocardium in adult human life in the setting of sex mismatched cardiac transplantation. In 2006, Takahashi and Yamanaka [3] were the first to show that somatic cells could be reprogrammed to embryonic stem cell-like pluripotent cells by the expression of only four transcription factors. These discoveries not only gave us further insights in the pathology of cardiovascular disease, they also triggered the extensive research in analyzing the potential of stem cell therapy for the treatment of cardiac disorders. The review articles included in this issue of Current Pharmaceutical Design aim to provide an overview on the novel insights regarding “endothelial progenitor cells”, cardiac resident stem cells, and inducible pluripotent stem cells. With respect to stem cell trafficking and homing, the role of chemokines, cytokines, and adhesion molecules is reviewed. Furthermore, this issue summarizes the current knowledge on the potential of stem cell therapy for the treatment of different cardiac disorders, including inflammatory cardiomyopathy, chronic ischemic myocardial disease, myocardial infarction, and diabetic cardiomyopathy. Among others, hurdles in stem cell therapy, advantages of one stem cell over the other, and the importance of the route of administration are discussed. Finally, the clinical experience with cardiac surgical cell therapy is summarized. The first review by Dirk Strunk [4] intends to critically outline aspects of terminology, origin and applicability of the so called “endothelial progenitor cells”, the somatic progenitors which are thought to maintain integrity and support regeneration of the inner lining of vessels through proliferation. With respect to cardiac resident stem cells, the review of Frati et al. [5] addresses the potential role of cardiac stem progenitor cells in the onset and development of congestive heart failure and its reversal by regenerative approaches aimed at the preservation and expansion of the resident pool of progenitors. Thorrez and Sampaolesi [6] give an overview of the current applications of inducible pluripotent stem cells in cardiovascular drug development and highlight active areas of inducible pluripotent stem cell research towards functional repair of the damaged heart. Furthermore, they discuss the results obtained from adult stem cells in clinical trials in light of the hurdles which have to be taken to move inducible pluripotent stem cells to the clinic......