Assembly of collagen-binding peptide with collagen as a bioactive scaffold for osteogenesis in vitro and in vivo.

Bioactive scaffolds inducing cell adhesion, differentiation have been premise for optimal formation of target tissue. Collagen has been employed as a tissue regenerative scaffold especially for bone regeneration and has been chemically surface-modified to present bioactivity. Herein, we show that peptide, denoted as collagen-binding motif (CBM, GLRSKSKKFRRPDIQYPDATDEDITSHM) identified from osteopontin (OPN) protein, was able to specifically bind collagen without chemical conjugation, while presenting apatite forming capability in vitro and in vivo. Collagen surface alone was not able to induce noticeable apatite nucleation however, mineralization was evident when assembled with CBM peptide, implying that the collagen-CBM assembly played a pivotal role in biomineralization. In vivo result further demonstrated that the CBM peptide in complex with material was able to induce bone formation by helping mineralization in the bone defect. Taken together, the CBM peptide herein and its assembly with collagen can be applied as an inducer of biomineralization as well as a bioactive scaffold for bone regeneration.