The Role Of Bone Morphogenetic Proteins In Inducing Osteogenic Differentiation Of Immortalized Odontoblast-like Cells

PURPOSE: This study was aimed to investigate the mesenchymal stem cells(MSC)phenotypes of immortalized immortalized odontoblast-like cells(iODs),and bone morphogenetic protein-2,-4,-6,-7,and-9(BMPs)differentially induce the osteogenic differentiation of iODs.METHODS: iODs were used to simulate odontoblast-like cells(ODs)for experiments.The endogenous expression of BMPs of iODs was examined by semiquantitative RT-PCR.The proliferation capability of iODs was examined using an MTT kit.MSC markers of iODs were examined by flow cytometry.Recombinant adenoviruses expressing BMP(Ad-BMP)and GFP(Ad-GFP)transfected iODs.In vitro,semiquantitative RT-PCR,alkaline phosphatase(ALP)activity assay,matrix mineralization assay and oil red O staining assay were used to examine the osteogenic and adipogenic differentiation capabilities of iODs.The volume and density of ectopic mineralized tissues formed in vivo were assessed by micro-CT andhistological analysis.Finally,the statistical significance among groups was analyzed by one-way analysis of variance and Scheffe's multiple comparison test.RESULTS: iODs maintained an excellent proliferative activity,expressed certain MSC markers and possessed multiple differentiation capabilities.BMP-2 and BMP-9 regulated iODs osteogenic differentiation better than BMP-4,-6,and-7.CONCLUSIONS: Our findings suggest that ODs and osteogenic growth factors such as BMP-2 and BMP-9 can be used as an efficacious strategy for bone tissue engineering.