title: Functionalization of deproteinized bovine bone with a coating-incorporated depot of BMP-2 renders the material efficiently osteoinductive and suppresses foreign-body reactivity.
abstract: The repair of critical-sized bony defects remains a challenge in the fields of implantology, maxillofacial surgery and orthopaedics. As an alternative bone-defect filler to autologous bone grafts, deproteinized bovine bone (DBB) is highly osteoconductive and clinically now widely used. However, this product suffers from the disadvantage of not being intrinsically osteoinductive. In the present study, this property was conferred by coating DBB with a layer of calcium phosphate into which bone morphogenetic protein 2 (BMP-2) was incorporated. Granules of DBB bearing a coating-incorporated depot of BMP-2--together with the appropriate controls (DBB bearing a coating but no BMP-2; uncoated DBB bearing adsorbed BMP-2; uncoated DBB bearing no BMP-2)--were implanted subcutaneously in rats. Five weeks later, the implants were withdrawn for a histomorphometric analysis of the volume densities of (i) bone, (ii) bone marrow, (iii) foreign-body giant cells and (iv) fibrous capsular tissue. Parameters (i) and (ii) were highest, whilst parameters (iii) and (iv) were lowest in association with DBB bearing a coating-incorporated depot of BMP-2. Hence, this mode of functionalization not only confers DBB with the property of osteoinductivity but also improves its biocompatibility--thus dually enhancing its clinical potential in the repair of bony defects.
authors: Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), VU University and University of Amsterdam, Amsterdam, The Netherlands. g.wu@acta.nl
authors: Gang
authors: G
authors: Wu
authors: Ernst B
authors: EB
authors: Hunziker
authors: Yuanna
authors: Y
authors: Zheng
authors: Daniel
authors: D
authors: Wismeijer
authors: Yuelian
authors: Y
authors: Liu
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects / Q000473:pathology; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology*; D001842:Bone and Bones / Q000187:drug effects* / Q000648:ultrastructure; D002130:Calcium Phosphates / Q000494:pharmacology; D002417:Cattle; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D005549:Foreign-Body Reaction / Q000473:pathology*; D015743:Giant Cells, Foreign-Body / Q000187:drug effects / Q000473:pathology; D008297:Male; D009929:Organ Size / Q000187:drug effects; D016348:Osseointegration / Q000187:drug effects*; D019919:Prosthesis Implantation; D051381:Rats; D017207:Rats, Sprague-Dawley; D040521:Subcutaneous Tissue / Q000187:drug effects
chemical_list: D055396:Bone Morphogenetic Protein 2; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; C020243:calcium phosphate