title: Injectable cell-free template for bone-tissue formation.
abstract: Here we present a novel injectable hydrogel which forms a template for de novo formation of bone tissue. Hydrogel formation takes place in situ in less than 1 min by the cross-linking of multifunctional hyaluronic acid and polyvinyl alcohol derivatives. Endogenous cells are recruited in vivo by incorporating bone morphogenetic protein-2 (BMP-2), a powerful promoter for osteogenic differentiation. The hydrogel was evaluated in vitro by performing a cell viability test and a release study and in vivo by a rat ectopic model. Examination by X-ray, microcomputed tomography, and histology revealed a significant bone formation at the target site for gels containing BMP-2, and a complete degradation was observed for gels without BMP-2 four weeks after injection. There were no signs of inflammation or foreign body response in either group and we believe that this system has the potential as an off-the-shelf injectable to be used where bone tissue is needed.
authors.affiliation: Division of Polymer Chemistry, Department of Materials Chemistry, Uppsala University, Se-751 21 Uppsala, Sweden.
authors.forename: Kristoffer
authors.initials: K
authors.lastname: Bergman
authors.forename: Thomas
authors.initials: T
authors.lastname: Engstrand
authors.forename: Jöns
authors.initials: J
authors.lastname: Hilborn
authors.forename: Dmitri
authors.initials: D
authors.lastname: Ossipov
authors.forename: Sonya
authors.initials: S
authors.lastname: Piskounova
authors.forename: Tim
authors.initials: T
authors.lastname: Bowden
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002828:Choristoma / Q000000981:diagnostic imaging / Q000473:pathology; D003432:Cross-Linking Reagents / Q000494:pharmacology; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D020100:Hydrogels / Q000494:pharmacology; D007267:Injections; D007700:Kinetics; D010012:Osteogenesis / Q000187:drug effects / Q000502:physiology*; D011108:Polymers / Q000138:chemical synthesis / Q000494:pharmacology; D019919:Prosthesis Implantation; D051381:Rats; D017207:Rats, Sprague-Dawley; D055114:X-Ray Microtomography
chemical_list: D003432:Cross-Linking Reagents; D020100:Hydrogels; D011108:Polymers