Sustained Delivery of BMP-2-Related Peptide from the True Bone Ceramics/Hollow Mesoporous Silica Nanoparticles Scaffold for Bone Tissue Regeneration.

Bone morphogenetic protein 2 (BMP-2) is one of the most important factors for bone tissue formation. A number of BMP-2 related small molecule bioactive peptides have been designed and shown to be equally effective in osteogenic activity. In this report, we synthesized a novel BMP-2-related peptide (designated P28) and designed a delivery system to regulate the controlled release of P28 from true bone ceramics (TBC) combined with an enlarged pore hollow mesoporous silica nanoparticles (HMSNs) composite scaffold. An in vitro release showed that the release of P28 from the TBC/HMSN scaffold was slower than that from the TBC scaffold. An in vitro cell experiment of the TBC/HMSN/P28 scaffold was tested with MC3T3-E1 cells in comparison to TBC, TBC/HMSN, and TBC/P28 scaffolds. Our results demonstrated that the TBC/HMSN/P28 scaffold had better effects on promoting proliferation and osteogenic differentiation of MC3T3-E1 cells than TBC, TBC/HMSN, and TBC/P28 scaffolds. After four kinds of scaffolds were implanted into a rabbit radius critical bone defect for 6 and 12 weeks, the radiographic and histological examination indicated that this osteogenic delivery system TBC/HMSN/P28 scaffold effectively induced bone regeneration in vivo. Therefore, the TBC/HMSN/P28 scaffold can promote proliferation and osteogenic differentiation of MC3T3-E1 cells in vitro and new bone tissue generation in vivo. This study provides a promising scaffold for bone tissue engineering and regenerative medicine.