Recombinant human osteogenic protein 1 is a potent stimulator of the synthesis of cartilage proteoglycans and collagens by human articular chondrocytes. - Flechtenmacher,J.; Huch,K.; Thonar,E.J-MA.; Mollenhauer,J.; Davies,S.R.; Schmid,T.M.; Puhl,W.; Sampath,T.K.; Aydelotte,M.B.; Kuettner,K.E. (Arthritis Rheum, 1996)