title: Growth factor-loaded scaffolds for bone engineering.
abstract: The objective of the study presented here was to investigate the bone inductive properties as well as release kinetics of rhTGF-beta1- and rhBMP-2-loaded Ti-fiber mesh and CaP cement scaffolds. Therefore, Ti-fiber mesh and porous CaP cement scaffolds were provided with these growth factors and inserted in subcutaneous and cranial implant locations in rats and rabbits. In vitro, a rapid release of rhTGF-beta1 was observed during the first 2 h of the Ti-fiber mesh scaffolds. During this time, more than 50% of the total dose of rhTGF-beta1 was released. Following this initial peak, a decline in the level of rhTGF-beta1 occurred. After 1 week, the entire theoretical initial dose was observed to have been released. This in contrast to the rhTGF-beta1 and rhBMP-2 release of the porous CaP cement scaffolds. Here, no substantial initial burst release was observed. The scaffolds showed an initial release of about 1% after 1 day, followed by an additional marginal release after 1 week. Histological analysis revealed excellent osteoconductive properties of non-loaded Ca-P material. Inside non-loaded Ti-mesh fiber scaffolds, also bone ingrowth occurred. Quantification of the bone ingrowth showed that bone formation was increased significantly in all scaffold materials by administration of rhTGF-beta1 and rhBMP-2. Consequently, we conclude that the release kinetics of growth factors from porous CaP cement differs from other scaffold materials, like metals and polymers. Nevertheless, orthotopic bone formation in a rabbit cranial defect model was stimulated in rhTGF-beta1- and rhBMP-2-loaded CaP cement and Ti-fiber mesh scaffolds compared with non-loaded implants.
authors.affiliation: Department of Periodontology and Biomaterials, University Medical Center, THK 117, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands. j.jansen@dent.umcn.nl
authors.forename: J A
authors.initials: JA
authors.lastname: Jansen
authors.forename: J W M
authors.initials: JW
authors.lastname: Vehof
authors.forename: P Q
authors.initials: PQ
authors.lastname: Ruhé
authors.forename: H
authors.initials: H
authors.lastname: Kroeze-Deutman
authors.forename: Y
authors.initials: Y
authors.lastname: Kuboki
authors.forename: H
authors.initials: H
authors.lastname: Takita
authors.forename: E L
authors.initials: EL
authors.lastname: Hedberg
authors.forename: A G
authors.initials: AG
authors.lastname: Mikos
mesh_terms: D000818:Animals; D001843:Bone Cements; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage* / Q000378:metabolism; D002130:Calcium Phosphates; D005260:Female; D008297:Male; D010012:Osteogenesis / Q000187:drug effects*; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000008:administration & dosage; D023822:Tissue Engineering; D014025:Titanium / Q000008:administration & dosage; D016212:Transforming Growth Factor beta / Q000008:administration & dosage* / Q000378:metabolism; D053773:Transforming Growth Factor beta1
chemical_list: C525720:Bmp2 protein, rat; D001843:Bone Cements; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D002130:Calcium Phosphates; D011994:Recombinant Proteins; C508962:Tgfb1 protein, rat; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D014025:Titanium