A thin carbon-fiber web as a scaffold for bone-tissue regeneration.

Due to the rapid progress being made in tissue regeneration therapy, biomaterials used as scaffolds are expected to play an important role in future clinical application. We report the development of a 3D web (sheet) consisting of high-purity carbon fibers in a nanoscale structure. When the thin carbon-fiber web (TCFW) and recombinant human bone morphogenetic protein 2 (rhBMP-2) composite is implanted in the murine back muscle, new ectopic bone is formed, and the values of the bone mineral content and bone mineral density are significantly higher than those obtained with a collagen sheet. Observation of the interface between the carbon fibers and bone matrix reveal that the fibers are directly integrated into the bone matrix, indicating high bone-tissue compatibility. Further, the rhBMP-2/TCFW composite repairs a critical-size bone defect within a short time period. These results suggest that the TCFW functions as an effective scaffold material and will play an important role in tissue regeneration in the future.