title: Bone-inducing agent (BIA) from cultured human Saos-2 osteosarcoma cells.
abstract: The Saos-2 line of human osteosarcoma cells was established in culture in 1975. These cells produce a large amount of alkaline phosphatase but little or no matrix in vitro, and are unable to grow when transplanted into athymic mice. We decided to test our local strain of Saos-2 cells for bone-inducing ability in the skeletal muscle of athymic mice by implanting freeze-dried, acetone-defatted cells, with and without a collagen carrier. A bone-inducing activity (BIA) thus was demonstrated in 88% of 90 implants of devitalized Saos-2 cells. In further studies, we have used guanidinium hydrochloride (Gu-HCl) to extract, solubilize, and remove the Saos bone-inducing agent(s) in an active state which when reprecipitated by aqueous dialysis was able to induce ultrastructurally typical endochondrial bone formation in nude mouse muscle in 92% of 48 implants. This preliminary report is offered to alert investigators to the presence of an extractable BIA in Saos-2 cells.
authors.affiliation: Department of Pathology and Oncology, University of Kansas Medical Center, Kansas City 66103.
authors.forename: H C
authors.initials: HC
authors.lastname: Anderson
authors.forename: K
authors.initials: K
authors.lastname: Sugamoto
authors.forename: D C
authors.initials: DC
authors.lastname: Morris
authors.forename: H H
authors.initials: HH
authors.lastname: Hsu
authors.forename: T
authors.initials: T
authors.lastname: Hunt
mesh_terms: D000818:Animals; D001846:Bone Development; D001857:Bone Matrix / Q000502:physiology; D002356:Cartilage / Q000254:growth & development / Q000648:ultrastructure; D003094:Collagen / Q000648:ultrastructure; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000648:ultrastructure; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D008854:Microscopy, Electron; D009368:Neoplasm Transplantation; D010006:Osteoblasts / Q000648:ultrastructure; D012516:Osteosarcoma / Q000737:chemistry* / Q000648:ultrastructure; D014407:Tumor Cells, Cultured
chemical_list: D003094:Collagen