title: Growth factor modulation of the formation of a molded vascularized bone graft in vivo.
abstract: Peptide growth factors are potent regulators of osteoblast differentiation, proliferation, and maturation. Two of these growth factors, transforming growth factor beta (TGF-beta) and basic fibroblast growth factor (bFGF), were used in an attempt to stimulate osteoneogenesis and angiogenesis in a molded vascularized bone graft in the rat. Custom chambers containing cancellous autograft bone and agarose beads and incubated with TGF-beta, bFGF, or a control solution, were closed around the femoral artery/vein pedicle for 2-4 weeks. Control grafts were completely necrotic and without mechanical integrity. TGF-beta grafts demonstrated active osteogenesis around necrotic bone, osteoclastic activity, and limited angiogenesis. Basic FGF grafts demonstrated substantial angiogenesis with limited osteoblastic activity. This study suggests that TGF-beta and bFGF stimulate populations of cells in the formation of a molded vascularized bone graft. TGF-beta induces the proliferation and/or activity of osteoblastic cells, while bFGF stimulates cells involved in angiogenesis. Despite these findings, an insoluble demineralized matrix component may be required for complete transformation and graft consolidation.
authors.affiliation: Department of Orthopaedics, Brown University School of Medicine, Rhode Island Hospital, Providence 02903, USA.
authors.forename: A P
authors.initials: AP
authors.lastname: Weiss
authors.forename: M L
authors.initials: ML
authors.lastname: Olmedo
authors.forename: J C
authors.initials: JC
authors.lastname: Lin
authors.forename: R T
authors.initials: RT
authors.lastname: Ballock
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000187:drug effects / Q000502:physiology / Q000637:transplantation; D016025:Bone Transplantation / Q000473:pathology / Q000502:physiology*; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology* / Q000502:physiology; D009336:Necrosis; D016348:Osseointegration / Q000187:drug effects*; D051381:Rats; D011917:Rats, Inbred Lew; D016212:Transforming Growth Factor beta / Q000494:pharmacology* / Q000502:physiology; D014182:Transplantation, Autologous
chemical_list: D016212:Transforming Growth Factor beta; D016222:Fibroblast Growth Factor 2