Osteoinduction using by Human BMP-2-physio-functional Bioactive Ceramics

Abstract

Pur p ose: T o assess the properties and the osteogenic potency of the calcium phosphate-recom - binant human morphogenetic protein-2 (C aP- rhBMP- 2 composite) on glass-ceramics. Mat e r ia ls and Met h ods: Bioactive glass-ceramics,as a scaffold, and a calcium phosphate (C aP) solution (pH 7.4) were prepared. R ecombinant human bone morphogenetic protein-2 (rhBMP- 2) was purified from C HO- K1 cells by transfecting the cells with BMP- 2 cD NA. T he glass-ceramics were soaked for 3 days at room temperature in saline, a CaP only solution, and a CaP solution containing rhBMP- 2. S canning electron microscopy (S EM) , Fourier transform infrared reflection spectroscopy (F T-IR ), thin film X -ray diffraction (T F-X RD) and immunofluorescent staining (IF) of the anti-human BM P -2 to composite-coated scaffold were performed to verify the characterization of the scaffold surface. In addition, R T-P CR of osteogenic marker gene and S EM photography were performed after adhering the mouse preosteoblast M C3T3- E 1 cells in order to assess the osteoinductivity. Resul ts : CaP-rhBMP-2 composite was coated on the surface of glass-ceramics, as confirmed by S EM, FT-IR , TF-X RD spectrum, and IF . The C aP- rhBMP- 2 composite on the glass-ceramic showed a globular shape covered with fine spikes while the C aP on the glass-ceramic showed a fine spike structure on the flat glass surface. The expression of collagen type I and alkaline phosphatase mRNAs had increased 4 hours after cell seeding. In addition, the level of osteocalcin mRNA ex- pression had increased significantly by 3 days in the CaP-rhBMP-2 composite compared with the control and C aP group. The S EM photographs showed more active filopodia formation in the C aP- rhBMP- 2 composite than the other groups. T here was extensive newly synthesized extracellular matrix around the osteoblasts and C aP- rhBMP- 2 composite nodule.