ABSTRACT
BACKGROUND:Many studies have showed that enough blood supply is an essential condition of bone repair and regeneration. OBJECTIVE:To construct the endothelial progenitor cells/bone marrow mesenchymal stem cells (EPCs/BMSCs) composite sheet. METHODS:After isolation and culture, EPCs and BMSCs were co-cultured directly to form EPCs/BMSCs sheet by cellsheet-inducing medium. After 10 days of induction, the sheet was investigated by gross observation, inverted microscope and hematoxylin-eosin staining. The distribution and communication of EPCs and BMSCs during the process of cellsheet induction were observed after the fluorescence labeling separately. Alkaline phosphatase assay and alizarin red staining were applied to examine the ability of osteogenic differentiation of EPCs/BMSCs sheet. RESULTS AND CONCLUSION:EPCs/BMSCs sheet was harvested after 10-day induction. Cel-cellcontact between EPCs and BMSCs could be observed during the process of the cellsheet preparation. The harvested sheet was composed of multiple layers of cells and cel-produced extracellular matrix. Alkaline phosphatase assay and alizarin red staining both demonstrated that EPCs/BMSCs sheet had good osteogenic differentiation ability. These results suggested that EPCs/BMSCs sheet can be constructed successful y, and the sheet has strong osteogenic differentiation capability in vitro, providing the foundation for the repair of bone defects.