Recombinant human osteogenic protein-1 (hOP-1) induces new bone formation in vivo with a specific activity comparable with natural bovine osteogenic protein and stimulates osteoblast proliferation and differentiation in vitro. - Sampath,T.K.; Ozkaynak,E.; Jones,E.; Sasa,H.; Tucker,R.; Tucker,M. (J Biol Chem, 1992)