Injectable bone using chitosan-alginate gel/mesenchymal stem cells/BMP-2 composites

Aim: Several injectable materials have been used as osteogenic bone substitutes. However, none has gained universal acceptance. This study was performed to investigate whether or not chitosan-alginate gel/mesenchymal stem cells/bone morphogenetic protein-2 composites are potentially injectable materials for new bone formation. Material and methods: The composites were injected into the subcutaneous space on the dorsum of nude mice to investigate new bone tissue formation. The composites were examined histologically over a 12-week period. Results: The composites injected into the mouse were able to stimulate new bone formation, which was trabecular in type. Conclusions: This study showed that chitosan-alginate gel/MSCs/BMP-2 composites could become clinically useful injectable materials to generate new bone.