title: Biomimetic tubular nanofiber mesh and platelet rich plasma-mediated delivery of BMP-7 for large bone defect regeneration.
abstract: There is a growing need for successful bone tissue engineering strategies and advanced biomaterials that mimic the structure and function of native tissues carry great promise. Successful bone repair approaches may include an osteoconductive scaffold, osteoinductive growth factors, cells with an osteogenic potential and capacity for graft vascularisation. To increase osteoinductivity of biomaterials, the local combination and delivery of growth factors has been developed. In the present study we investigated the osteogenic effects of calcium phosphate (CaP)-coated nanofiber mesh tube-mediated delivery of BMP-7 from a PRP matrix for the regeneration of critical sized segmental bone defects in a small animal model. Bilateral full-thickness diaphyseal segmental defects were created in twelve male Lewis rats and nanofiber mesh tubes were placed around the defect. Defects received either treatment with a CaP-coated nanofiber mesh tube (n = 6), an un-coated nanofiber mesh tube (n=6) a CaP-coated nanofiber mesh tube with PRP (n=6) or a CaP-coated nanofiber mesh tube in combination with 5 μg BMP-7 and PRP (n = 6). After 12 weeks, bone volume and biomechanical properties were evaluated using radiography, microCT, biomechanical testing and histology. The results demonstrated significantly higher biomechanical properties and bone volume for the BMP group compared to the control groups. These results were supported by the histological evaluations, where BMP group showed the highest rate of bone regeneration within the defect. In conclusion, BMP-7 delivery via PRP enhanced functional bone defect regeneration, and together these data support the use of BMP-7 in the treatment of critical sized defects.
authors.affiliation: Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, Brisbane, Queensland 4059, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Berner
authors.forename: J D
authors.initials: JD
authors.lastname: Boerckel
authors.forename: S
authors.initials: S
authors.lastname: Saifzadeh
authors.forename: R
authors.initials: R
authors.lastname: Steck
authors.forename: J
authors.initials: J
authors.lastname: Ren
authors.forename: C
authors.initials: C
authors.lastname: Vaquette
authors.forename: J Qiyi
authors.initials: JQ
authors.lastname: Zhang
authors.forename: M
authors.initials: M
authors.lastname: Nerlich
authors.forename: R E
authors.initials: RE
authors.lastname: Guldberg
authors.forename: D W
authors.initials: DW
authors.lastname: Hutmacher
authors.forename: M A
authors.initials: MA
authors.lastname: Woodruff
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena / Q000187:drug effects; D040761:Biomimetic Materials / Q000494:pharmacology*; D055419:Bone Morphogenetic Protein 7 / Q000494:pharmacology*; D001861:Bone Regeneration / Q000187:drug effects*; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D016503:Drug Delivery Systems / Q000379:methods*; D021621:Imaging, Three-Dimensional; D008297:Male; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D016348:Osseointegration / Q000187:drug effects; D053657:Platelet-Rich Plasma / Q000378:metabolism*; D051381:Rats; D011917:Rats, Inbred Lew; D054457:Tissue Scaffolds / Q000737:chemistry; D019415:Torque; D055114:X-Ray Microtomography
chemical_list: D055419:Bone Morphogenetic Protein 7