ABSTRACT
Objective:To study the effects of BMP-7 gene transfected bone marrow mesenchymal stem cells(MSCs)on callus acceleration in rat mandibular distraction osteogenesis.Methods:Forty-eight adult male SD rats were randomly divided into experimental and control groups.MSCs were obtained from individual rat and transfected by pEGF-P-BMP7 for the 24 experimental rats and by the empty vector pEGFP-N1 for the 24 control rats.The rats were underwent right mandibular distraction.1?106/100 ?l BMP-7 gene transfected cells in 10 ?l of normal saline were injected into the distraction gap in each experimental rat,while the same number of empty vector transfected cells in each control rat.The distracted mandibles were harvested 2,4,and 8 weeks respectively after cell injection and evaluated by radiological,histological and histomorphometric analysis.Results:Radiological and histological examinations showed that more new bone was formed in experimental group than in control.Histomorphometric analysis also demonstrated that both new bone volume(NBV1 and NBV2)and the thickness of new trabeculae(TNT)were significantly higher in experimental rats than those in control(P