Enhancement of ectopic osteoid formation following the dual release of bone morphogenetic protein 2 and Wnt1 inducible signaling pathway protein 1 from gelatin sponges.

Bone morphogenetic protein (BMP) 2-incorporated gelatin sponge is effective for in vivo osteoinduction. However, the modeling capacity of bone decreases with age. As atrial to stimulate effective bone formation for animals with decreased osteogenic potential, Wnt1 inducible signaling pathway protein (WISP) 1, an osteoblastic regulator, was combined with gelatin sponge incorporating BMP2. Osteopontin (Opn) geneexpression was increased in vitro for mouse bone marrow stromal cells (BMSC) cultured in gelatin sponges incorporating BMP2 and WISP1 compared with those incorporating BMP2 or WISP1 alone. In vivo synergistic effect of BMP2 and WISP1 on the ectopic osteoid formation was observed when gelatin sponges incorporating BMP2 and WISP1 were implanted subcutaneously into middle-aged mice with decreased bone formation potential. It is concluded that the scaffold incorporating multiple osteoinductive agents could be effective in inducing bone formation in those with age-related decreased potential of bone formation.