Over expression of bone morphogenetic protein-3b (BMP-3b) using an adenoviral vector promote the osteoblastic differentiation in C2C12 cells and augment the bone formation induced by bone morphogenetic protein-2 (BMP-2) in rats.

BMP-3b is a novel BMP-3-related protein and its biological functions are unknown. In order to investigate the biological actions of BMP-3b, we constructed a BMP-3b-expressing recombinant adenoviral vector (AxCAKBMP-3b). We show that over expression of BMP-3b stimulated the induction of differentiation and the osteoinduction activity of a human BMP-2-expressing recombinant adenoviral vector (AxCAOBMP-2). C2C12 cells were infected in vitro with AxCAKBMP-3b, AxCAOBMP-2 and a control vector containing no foreign genes (AxCAwt). Cells infected with AxCAOBMP-2 and AxCAKBMP-3b produced more alkaline phosphatase and secreted more osteocalcin into the culture medium than cells infected with AxCAOBMP-2 and AxCAwt. When AxCAOBMP-2, AxCAKBMP-3b, and AxCAwt were injected into the calf muscles of nude rats (F 344/N Jcl-rnu), the osteoinduction seen with AxCAOBMP-2 and AxCAKBMP-3b was greater than that seen with AxCAOBMP-2 and AxCAwt. Copyright 2002 Elsevier Science Inc.