Fig. 1

The schematic shows the whole procedure of the experiments. First, the rat bone marrow-derived mesenchymal stem cells (rBMSCs) were harvested and cultured in different culture media to form induced endothelial cells (iECs), pre-vascularized cell sheets (iECs/UM) and osteogenic cell sheets (OM). Then, these two types of cell sheets were cut into strips approximately 60 mm in length and 10 mm in width. The strip of the osteogenic cell sheet was wrapped on the beta-tricalcium phosphate (β-TCP) scaffold as the cambium layer of a native periosteum followed by the prevascularized cell sheet strip as the fibrous layer of a native periosteum. Thus, the BP/β-TCP constructs were formed. Finally, the BP/β-TCP constructs were implanted in the calvarial bone defect of a rat. BP biomimetic periosteum, UM undifferentiated medium