Bone augmentation by bone marrow mesenchymal stem cells cultured in three-dimensional biodegradable polymer scaffolds

Poly-lactic-glycolic acid (PLGA) is a biocompatible as well as biodegradable polymer and used in various medical applications. In this study, we evaluated efficiency of the specially designed three-dimensional porous PLGA as a scaffold for bone augmentation. First, cell attachment/proliferation, differentiation, and mineralization of Fisher 344 rat marrow mesenchymal stem cells (MSCs) cultured on the PLGA scaffold were analyzed. Viable MSCs were impregnated into pore areas of the scaffold and a moderate increase of DNA contents was seen. High alkaline phosphatase, osteocalcin content, and calcium content of MSCs in PLGA scaffolds under osteogenic differentiation conditions were seen after 14 or 21 days of culture. Subsequently, we implanted the PLGA/MSCs composites on rat calvaria bone for 30 days. Newly formed bone was seen in only the composite PLGA/MSCs implantation group, which had been precultured under osteogenic condition. We also demonstrated that the newly formed bone originated from the donor composites. These results demonstrate that the three-dimensional PLGA scaffold can support osteogenic differentiation of MSCs, and the scaffold combined with osteogenic MSCs can be used for in vivo bone tissue augmentation.