title: The Acute Inflammatory Response to Absorbed Collagen Sponge Is Not Enhanced by BMP-2.
abstract: Absorbed collagen sponge (ACS)/bone morphogenetic protein-2 (BMP-2) are widely used in clinical practise for bone regeneration. However, the application of this product was found to be associated with a significant pro-inflammatory response, particularly in the early phase after implantation. This study aimed to clarify if the pro-inflammatory activities, associated with BMP-2 added to ACS, were related to the physical state of the carrier itself, i.e., a wet or a highly dehydrated state of the ACS, to the local degree of vascularisation and/or to local biomechanical factors. ACS (0.8 cm diameter)/BMP-2 were implanted subcutaneously in the back of 12 eight-week-old Sprague Dawley rats. Two days after surgery, the implanted materials were retrieved and analysed histologically and histomorphometrically. The acute inflammatory response following implantation of ACS was dependent of neither the presence or absence of BMP-2 nor the degree of vascularization in the surrounding tissue nor the hydration state (wet versus dry) of the ACS material at the time of implantation. Differential micro biomechanical factors operating at the implantation site appeared to have an influence on the thickness of inflammation. We conclude that the degree of the early inflammatory response of the ACS/BMP-2 may be associated with the physical and chemical properties of the carrier material itself.
authors.affiliation: Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081LA Amsterdam, The Netherlands. hhrstudy@126.com.
authors.forename: Hairong
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081LA Amsterdam, The Netherlands. d.wismeijer@acta.nl.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wismeijer
authors.affiliation: Departments of Osteoporosis and Orthopaedic Surgery, Inselspital (DKF), University of Bern, Murtenstrasse 35, 3008 Bern, Switzerland. ernst.hunziker@dkf.unibe.ch.
authors.forename: Ernst B
authors.initials: EB
authors.lastname: Hunziker
authors.affiliation: Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Gustav Mahlerlaan 3004, 1081LA Amsterdam, The Netherlands. g.wu@acta.nl.
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
mesh_terms: D020341:Absorbable Implants / Q000009:adverse effects*; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000378:metabolism*; D001861:Bone Regeneration; D003094:Collagen / Q000378:metabolism*; D007249:Inflammation / Q000209:etiology* / Q000378:metabolism* / Q000473:pathology; D008264:Macrophages / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008297:Male; D018919:Neovascularization, Physiologic; D010012:Osteogenesis; D051381:Rats; D011994:Recombinant Proteins
chemical_list: D055396:Bone Morphogenetic Protein 2; D011994:Recombinant Proteins; D003094:Collagen
keywords: absorbed collagen sponge (ACS); biomechanical; bone morphogenetic protein-2 (BMP-2); inflammation; vascularization