title: Natural bone collagen scaffold combined with OP-1 for bone formation induction in vivo.
abstract: The scaffold is a key element to osteogenic tissue engineering as it provides a microenvironment for bone formation. Natural bone collagen scaffold (NBCS) is a novel biomaterial scaffold acid-extracted from organic human bone. The objective of this study was to characterize NBCS and evaluate the osteoconductivity of the scaffold, in combination with osteogenic protein-1 (OP-1), using a rabbit posteolateral lumbar fusion model. Thirty two rabbits were divided into 4 experimental groups, autograft, NBCS alone, OP-1 alone or NBCS combined with OP-1. Bone formation was evaluated by micro-CT, quantitative histological analysis, immunohistochemistry and semi-quantitative RT-PCR at 6 weeks postoperatively. By scanning electronic microscope, we showed that NBCS maintains a porous, interconnecting microarchitecture. Micro-CT analysis demonstrated that NBCS combined with OP-1 significantly induced (p < 0.01) bone formation at the fusion site as compared to control groups. This was confirmed by quantitative histological analysis which demonstrated that the NBCS combined with OP-1 significantly enhanced bone matrix area (17.7 mm(2)) (p < 0.05) and bone marrow cavity size (71.3 mm(2)) (p < 0.05) as compared to the controls. Immunohistochemical assessment and RT-PCR also demonstrated that NBCS combined with OP-1 enhanced type I collagen and osteonectin expression. Together, these results suggest that NBCS is an effective scaffold for osteogenesis, and combined with growth factors such as OP-1, possesses both osteoconductive and osteoinductive properties that are sufficient for bone regeneration.
authors.affiliation: Centre for Orthopaedic Research, School of Surgery, The University of Western Australia, Western Australia 6009, Australia.
authors.forename: Yu
authors.initials: Y
authors.lastname: Qian
authors.forename: Guanfeng
authors.initials: G
authors.lastname: Yao
authors.forename: Zhen
authors.initials: Z
authors.lastname: Lin
authors.forename: Jimin
authors.initials: J
authors.lastname: Chen
authors.forename: Ying
authors.initials: Y
authors.lastname: Fan
authors.forename: Tamara
authors.initials: T
authors.lastname: Davey
authors.forename: Jiake
authors.initials: J
authors.lastname: Xu
authors.forename: Minghao
authors.initials: M
authors.lastname: Zheng
mesh_terms: D000818:Animals; D055419:Bone Morphogenetic Protein 7 / Q000378:metabolism*; D018786:Bone Substitutes / Q000737:chemistry*; D001842:Bone and Bones / Q000473:pathology*; D003094:Collagen / Q000737:chemistry*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D010006:Osteoblasts / Q000473:pathology; D010012:Osteogenesis; D016062:Porosity; D011817:Rabbits; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D055419:Bone Morphogenetic Protein 7; D018786:Bone Substitutes; D003094:Collagen