Bone Abstracts

Background: Three-dimensional scaffolds for the tissue regeneration are also crucial materials for bone formation. In particular, the scaffolds must provide the space for the cell migration and new bone formation. Collagen is one of the useful scaffolds to reach these performance, however, it is not always a desired biodegradability. Recently, we succeeded in developing low adhesive scaffold type I collagen (LASCol) (patent pending) which has the ability to form fibrils. In this study, we report whether the implant of LASCol was effective to induce new bone formation in a critical-sized defect (CSD) of rat shinbone.

Methods: LASCol or atelocollagen was lyophilized. The cylindrical bone of 3 mm diameter was removed from right and left shinbones of SD rat (15 weeks). Subsequently, the lyophilized graft of LASCol or atelocollagen (each 3 mg) was implanted into the defect position of both shinbones. After 15 days, one of shinbones including the defected position was evaluated by histological observation with HE staining and by immunohistological definition with anti-collagen antibody. To evaluate new bone formation, micro-computed tomography (μCT) scanning of the other shinbone was carried out. In addition, we measured Gla-osteocalcin in the rat serum by ELISA kit.

Results: After 15 days of the implant operation, LASCol graft in rat was disappeared, and instead spongy bones were found in the same space. On the other hand, atelocollagen graft clearly remained in shinbone. The μCT analysis was identical to histological results. Furthermore, Gla-osteocalcin in the serum of LASCol implantation group was shown to increase. In conclusion, we showed that LASCol graft has the potential to induce osteogenic regeneration in the CSD of rat shinbone.

Funding: This work was supported by the Adaptable and Seamless Technology Transfer Program through target-driven R&D, AMED (AS2414037P to K.M.) and JST (AS2715177U to K.M.).