Abstract
Mesenchymal stem cells (MSCs) have been extensively investigated in the field of regenerative medicine. Human bone MSCs (BMSCs) have become a common type of seed cell for bone tissue engineering. However, the viability and cell number of BMSCs are negatively correlated with donor age, and as the extraction process is painful, this method has not been widely used. As human umbilical cord MSCs (UCMSCs) may be harvested inexpensively and inexhaustibly, the present study evaluated and compared the regenerative potential of UCMSCs and BMSCs to determine whether UCMSCs may be used as a novel cell type for bone regeneration. In the present study, the proliferation and osteogenic capacity of BMSCs and UCMSCs was compared in vitro. BMSCs and UCMSCs were respectively combined with biofunctionalized macroporous calcium phosphate cement, and their bone regenerative potentials were determined by investigating their capacity for ectopic bone formation in a nude mouse model as well as their efficacy in a rat model of tibia bone defect. The extent of bone regeneration was examined by X-ray, histological and immunohistochemical analyses. The results revealed that UCMSCs exhibited a good osteogenic differentiation potential, similarly to that of BMSCs, and that UCMSCs were able to contribute to the regeneration of bone and blood vessels. Furthermore, no significant differences were identified between BMSCs and UCMSCs in terms of their bone regenerative effect.