Study Of Human RhBMP-2 In Vitro On Osteogenic Induction Of BMSCs In Different Types Of Mandibular Condylar Intracapsular Fractures Of Goats

Objective:To investigate the osteogenesis of bone marrow mesenchymal stem cells(BMSCs)after different types of goat mandibular intracapsular condylar fractures(ICF)in vitro by recombinant human bone morphogenetic protein-2(rhBMP-2),and provide guidance for the clinical treatment of intracapsular fractures.Methods:Sixteen6~8-month-old goats' s bilateral mandibular condyles were randomly divided into 4 groups:eight goats were divided into the left condyle A-type ICF group(group A)and the right condyle B-type ICF group(group B),and the other eight goats 8 were divided into the left condyle as C-type ICF group(group C)+ the right condyle as control group(group D).The animals was sacrificed at the following intervals,1 months,2 months,3 months and 6months post operatively.The third generation of bone marrow mesenchymal stem cells were induced by rhBMP-2,and used MTT colorimetric assay to evaluate the proliferation at first to seventh days.The alkaline phosphatase(ALP)activity and osteocalcin content was measured at 7d and 10 d,and ALP staining was performed after 1week.Results:Compared with the non-inducing group,the ALP activity and the osteocalcin content of the BMSCs in group A,B,C,and D after rhBMP-2 inducer was significantly increased(P<0.05);1 months,2 months,3 months,and 6 months,the ALP activity and osteocalcin content in group B was significantly higher than that in group A,C,and D after induced by rhBMP-2(P< 0.05).Conclusion:The use of rhBMP-2 can enhance the BMSCs proliferation and induce an expression and maintenance of the osteoblastphenotype differentiation of the goats BMSCs;the osteogenic activity of BMSCs after B-type condylar intracapsular fracture was significantly higher than that of type A condylar intracapsular fractures group,type C condylar intracapsular fractures group and control group.