EVALUATION OF rhBMP-7 EFFECT ON HUMAN PERIODONTAL LIGAMENT CELLS

Objectives: Regeneration of periodontal tissues lost during periodontal disease constitutes a complex regulated biological process involving the interaction of different cell types, growth factors, hormones and the components of the connective tissue extracellular matrix. A variety of regenerative techniques and materials have been proposed for the therapeutic approach of the periodontal defects such as the use, alone or in combination, of antibiotics, membranes, bone grafts and different biological mediators. Recently, one of the biological therapeutic procedures of particular interest is the application of a group of bone matrix proteins known as bone morphogenetic proteins (BMPs). BMPs display variant action and depended on the use condition, they may promote in vitro and in vivo periodontal regeneration. The purpose of the present study is the investigation of rhBMP-7 effect on proliferation and differentiation of human periodontal ligament (hPDL) cells treated with various proteins amount. Methods: hPDL cells were harvested from two maxillary premolars. The caries free teeth were extracted for orthodontic reasons from adult patients with clinically healthy periodontium and without any known medical disorder. Cell cultures characterization was performed by immunohistochemistry for vimentine, osteopontin and sialoprotein. After confluency, on the 2nd day of quiescence, new medium was added along with 500 and 1000ng/ml of BMP-7 for 48hrs. Cells mitogenic response was estimated using the Trypan Blue exclusion assay procedure while the effect on differentiation by measuring the alkaline phosphatase (ALPase) activity and osteocalcin (OC) secretion. Data were analyzed by a Poisson regression model and the statistical significance was determined at P<0.05. Results: The results showed that BMP-7 did not exert any proliferative effect on hPDL cells while enhanced ALPase activity on both BMP-7 concentrations but not OC secretion. Conclusion: It might be concluded that BMP-7 promotes the early osteoblastic differentiation of hPDL cells.