Transplantation of cultured bone cells using combinations of scaffolds and culture techniques.

The transplantation of cultured bone cells is expected to become a candidate for bone regeneration therapy. For the clinical application of this therapy, there remain several problems to be overcome, for example, the improvements of scaffolds and culture techniques. In this review article, two kinds of porous ceramics, a novel sintered porous hydroxyapatite and a porous beta-tricalcium phosphate (TCP), as well as a collagen-phosphosphoryn sponge are introduced as new scaffolds for bone regeneration. The former two ceramic scaffolds proved to be applicable for bone regeneration therapy. The collagen-phosphophoryn sponge proved to have bone formation ability in vivo. Moreover, for the application of this therapy to the regeneration of large bone defects, we improved the culture method by applying a low-pressure system and a perfusion system. Both culture systems accelerated the formation of bone in vivo in this transplantation model. Combinations of the scaffolds and culture techniques might be considered when designing therapeutic strategies.