Abstract
Angiogenesis is quite important for bone tissue regeneration, because formed blood vessel in bone supply oxygen and nutrients to osteoblasts to be differentiated to form new bone. In particular, cultured bone implantation using porous ceramics scaffolds, a kind of bone tissue engineering, needs enough blood vessel formation into central porous area, maintaining osteoblast activities. This is a report successfully inducing bone formation and showing our application of adenoviral vector carrying angiogenic factor VEGF(vascular endothelial growth factor) for activating osteoblasts to transduce MSCs (messenchymal stromal cells) in a cultured bone transplantation model. For this purpose, we constructed the recombinant adenoviral vector carrying VEGF cDNA (Adv-VEGF) and the Adv-VEGF infected MSCs derived osteoblasts/porous ceramic scaffold composite was implanted into subcutaneous sites and orthotropic sites of Fischer rats. In the rat bone defect model, much blood formation were observed at 10 days postimplantation, in addition to the induction of bone formation by virus infection. TRAP positive osteoclasts and invasion of bone marrow tissues were observed in the transplanted ceramics showing the remodeling of implanted ceramics. Overexpression of VEGF proved to be effective in inducing bone formation with remodeling in a cultured bone transplantation model.
