[Expression of BMP4 mRNA in the in-vivo tissue engineering bone]

This study was aimed to compare the expression of BMP4 mRNA in the in-vivo tissue engineering bone constructed with Ca/P ceramics against the expression of BMP4 mRNA in the naturally healing bone. 20 porous Ca/P ceramics cylinders with Phi 5 mm x 8 mm were made and implanted into the dorsal muscles of 5 dogs. As control, one molar tooth was pulled out from each dog to create bone defect for the naturally healing bone at the same time. The specimens and the naturally healing bone were harvested at 1, 2, 4, 12 and 24 weeks post-implantation. After RNA extraction and reverse transcription, bone morphogenetic protein 4 (BMP4) and GAPDH mRNA were detected by real-time quantitative polymerase chain reaction (PCR) method. The results showed that the expression level of BMP4 mRNA of the in-vivo tissue engineering bone constructed with Ca/P ceramics was higher than that of the naturally healing bone in the period of experiment. However, the in-vivo tissue engineering bone had the same chronological order of BMP mRNA expression that the naturally healing bone did. As a bone substitute analogous to autologous bone, the in-vivo tissue engineering bone constructed with Ca/P ceramics has the potential for clinical application.