Effects of epidermal growth factor on proliferation and migration of cardiosphere-derived cells expanded from adult human heart.

Recent studies have provided evidence that the human heart has an endogenous reserve of cardiac stem cells (CSCs) that can be activated to reconstitute the dead myocardium. Current efforts are now directed towards the identification of factors favoring the growth and expansion of the CSC pool in the heart. Accordingly, in the present study, effects of different growth factors on cardiosphere-derived cells (CDCs), expanded from atrial biopsies from patients undergoing elective coronary artery bypass surgery, were analyzed. CSCs appear to respond to epidermal growth factor (EGF) more efficiently than other widely used growth factors such as vascular endothelial growth factor, insulin-like growth factor, basic fibroblast growth factor, hepatocyte growth factor, transforming growth factor, and platelet-derived growth factor. EGF significantly promoted cardiosphere formation (p < 0.05) and proliferation (p < 0.005), migration (p < 0.0005), and wound healing (p < 0.005) activities of CDCs in comparison to the other growth factors studied. Pretreatment with EGF enhanced the expression of cardiac markers cTN1(+) and MHC(+) in CDCs in comparison to untreated controls.