Abstract:

Objective  To investigate the differentiation of cardiac fibroblasts (CFSs) into endothelial cells and the potential for vascularization, and to provide a cytological and theoretical basis for clinical treatment of myocardial injury. Methods  CFSs were isolated, cultured and purified from the fresh left ventricular tissue. The 3rd generation of CFSs was induced by endothelial cells induced medium for 28 days. After continuous induction culture of 28 days, the endothelial cell medium (ECM) was replaced, digested and passaged down to P3 generation. The growth and morphological changes of the induced cells were detected. The expression of the endothelial cell markers and functional characteristics in the induced cells were evaluated by immunocytochemistry, flow cytometry and angiogenesis analysis. Results  The third generation of CFSs in neonatal rats was triangular, spindle and polygonal, and the rate of proliferation was rapid. Vimentin and discoidin domain receptor 2(DDR2) expressions were positive. The 3rd generation of CFSs was cultured for 3 hours and the induced medium was added, cells began to converge after 3 days, the cells formed string beads were induced at 21 days, and the cells were pooled into the ring shape at 28 days. The immunohistochemistry staining showed that vWF and CD31 were positively expressed in the differentiated cells, but not expressed in the control group. The immunofluorescence staining shows that vWF, CD34 and CD105 were positive in the experimental group, but not in the control group. Flow cytometry analysis showed that the expression rate of CD31 was 50.5% in the induced cells, whereas the expression in the control group was just 5.82%. Conclusion  Cardiac fibroblasts induced with vascular endothelial growth factor(VEGF) and basic fibroblast growth factor(bFGF ) can differentiate into vascular endothelial cells in vitro, and have the characteristics and functions of vascular endothelial cells.

Key words: Vascular endothelial growth factor, Basic fibroblast growth factor(bFGF), Cardiac fibroblast, Endothelial Cell differentiation, Cell culture, Rat