title: Use of myoblasts in assaying the osteoinductivity of bone morphogenetic proteins.
abstract: A novel, time- and BMP-saving in vitro method for the detection and quantitation of bone morphogenetic protein (BMP) activity was developed based on the measurable effects of BMP on rat skeletal muscle myoblasts (L6). Calcium incorporation, stimulation of alkaline phosphatase activity and production of osteocalcin were used as markers of bone cell metabolism and on-going morphogenesis. The morphological change was confirmed by Chlorantine fast red and von Kossa staining. The response of various BMPs was purity-dependent and consistent with intramuscular implantations of the same materials. Neither TGF-beta1 nor insulin could induce the same actions. The data from this study indicate that at least in part in vivo implantations of BMP extracts can be replaced by in vitro measurement of osteoinductivity. Considerable saving of time, BMP and experimental animals can be achieved using cell culture conditions for the determination of bone-forming activity.
authors.affiliation: Institute of Medical Technology, University of Tampere, Department of Orthopaedics and Traumatology, Tampere University Hospital, Finland. lj39291@uta.fi
authors.forename: L
authors.initials: L
authors.lastname: Jortikka
authors.forename: M
authors.initials: M
authors.lastname: Laitinen
authors.forename: J
authors.initials: J
authors.lastname: Wiklund
authors.forename: T S
authors.initials: TS
authors.lastname: Lindholm
authors.forename: A
authors.initials: A
authors.lastname: Marttinen
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001681:Biological Assay; D015415:Biomarkers; D001846:Bone Development / Q000502:physiology*; D019485:Bone Morphogenetic Proteins / Q000096:biosynthesis*; D002132:Calcium Radioisotopes; D002417:Cattle; D006801:Humans; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism*; D015675:Osteocalcin / Q000378:metabolism; D051381:Rats; D013936:Thymidine / Q000378:metabolism
chemical_list: D015415:Biomarkers; D019485:Bone Morphogenetic Proteins; D002132:Calcium Radioisotopes; D015675:Osteocalcin; D000469:Alkaline Phosphatase; D013936:Thymidine