Effect of Bone Morphogenetic Protein-2 and Doxycycline on the Differentiation of Osteoprogenitors from Human Femoral Bone

The purpose of this investigation was to evaluate the effects of bone morphogenetic protein-2 (BMP-2) and doxycycline on the in vitro differentiation of osteoprogenitor cells isolated from human femoral cancellous bone. The differentiation of osteoprogenitors into bone-forming osteoblasts was evaluated by alkaline phosphatase activity, osteocalcin gene expression, and the number of Von Kossa-positive bone nodules. Treatment of osteoprogenitors with BMP-2, at all concentrations tested, and doxycycline, at 10 and 50 � M, significantly increased the number of mineralized bone nodules and coincided with expression of osteocalcin. In conclusion, doxycycline at 10 and 50 �M had similar stimulatory osteoinductive effects as BMP-2 and could thus be considered as an alternative agent to BMP-2.