Bone regeneration using coculture of mesenchymal stem cells and angiogenic cells

Cellular strategies remain a crucial component in bone tissue engineering (BTE). So far, the outcome of cell-based strategies from initial clinical trials is far behind compared to animal studies, which is suggested to be related to insufficient nutrient and oxygen supply inside the tissue-engineered constructs. Cocultures, by introducing angiogenic cells into osteogenic cell cultures, might provide a solution for improving vascularization and hence increasing bone formation for cell-based constructs. So far, pre-clinical studies demonstrated that cocultures enhance vascularization and bone formation compared to monocultures. However, there has been no report on the application of cocultures in clinics. Therefore, this mini-review aims to provide an overview regarding (i) critical parameters in cocultures and the outcomes of cocultures compared to monocultures in the currently available pre-clinical studies using human mesenchymal stem cells implanted in orthotopic animal models; and (ii) the usage of monocultures in clinical application in BTE.