Characteristic of c-Kit+ progenitor cells in explanted human hearts

Abstract

According to literature data, self-renewing, multipotent, and clonogenic cardiac c-Kit+ progenitor cells occur within human myocardium. The aim of this study was to isolate and characterize c-Kit+ progenitor cells from explanted human hearts. Experimental material was obtained from 19 adult and 7 pediatric patients. Successful isolation and culture was achieved for 95 samples (84.1 %) derived from five different regions of the heart: right and left ventricles, atrium, intraventricular septum, and apex. The average percentage of c-Kit+ cells, as assessed by FACS, ranged between 0.7 and 0.9 %. In contrast to published data we do not observed statistically significant differences in the number of c-Kit+ cells between disease-specific groups, parts of the heart or sexes. Nevertheless, c-Kit + cells were present in significant numbers (11-24 %) in samples derived from three explanted pediatric hearts. c-Kit+ cells were also positive for CD105 and a majority of them was positive for CD31 and CD34 (83.7 ± 8.6 and 75.7 ± 11.4 %, respectively). Immunohistochemical analysis of the heart tissue revealed that most cells possessing the c-Kit antigen were also positive for tryptase, a specific mast cell marker. However, flow cytometry analysis has shown cultured c-Kit+ cells to be negative for hematopoietic marker CD45 and mast cell marker CD33. Isolated c-Kit+ cells display mesenchymal stem cell features and are thought to differentiate into endothelial cells. © 2014 The Author(s).