title: Porous decellularized tissue engineered hypertrophic cartilage as a scaffold for large bone defect healing.
abstract: Clinical translation of tissue engineered therapeutics is hampered by the significant logistical and regulatory challenges associated with such products, prompting increased interest in the use of decellularized extracellular matrix (ECM) to enhance endogenous regeneration. Most bones develop and heal by endochondral ossification, the replacement of a hypertrophic cartilaginous intermediary with bone. The hypothesis of this study is that a porous scaffold derived from decellularized tissue engineered hypertrophic cartilage will retain the necessary signals to instruct host cells to accelerate endogenous bone regeneration. Cartilage tissue (CT) and hypertrophic cartilage tissue (HT) were engineered using human bone marrow derived mesenchymal stem cells, decellularized and the remaining ECM was freeze-dried to generate porous scaffolds. When implanted subcutaneously in nude mice, only the decellularized HT-derived scaffolds were found to induce vascularization and de novo mineral accumulation. Furthermore, when implanted into critically-sized femoral defects, full bridging was observed in half of the defects treated with HT scaffolds, while no evidence of such bridging was found in empty controls. Host cells which had migrated throughout the scaffold were capable of producing new bone tissue, in contrast to fibrous tissue formation within empty controls. These results demonstrate the capacity of decellularized engineered tissues as 'off-the-shelf' implants to promote tissue regeneration.
authors.affiliation: Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland; Advanced Materials and Bioengineering Research Centre, Trinity College Dublin & RCSI, Dublin 2, Ireland.
authors.forename: Gráinne M
authors.initials: GM
authors.lastname: Cunniffe
authors.affiliation: School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Vinardell
authors.affiliation: REMEDI, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland.
authors.forename: J Mary
authors.initials: JM
authors.lastname: Murphy
authors.affiliation: Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland, Dublin 2, Ireland.
authors.forename: Emmet M
authors.initials: EM
authors.lastname: Thompson
authors.affiliation: Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland, Dublin 2, Ireland.
authors.forename: Amos
authors.initials: A
authors.lastname: Matsiko
authors.affiliation: Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland; Advanced Materials and Bioengineering Research Centre, Trinity College Dublin & RCSI, Dublin 2, Ireland; Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland, Dublin 2, Ireland.
authors.forename: Fergal J
authors.initials: FJ
authors.lastname: O'Brien
authors.affiliation: Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland; Advanced Materials and Bioengineering Research Centre, Trinity College Dublin & RCSI, Dublin 2, Ireland; Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland, Dublin 2, Ireland. Electronic address: kellyd9@tcd.ie.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Kelly
mesh_terms: D000818:Animals; D002356:Cartilage / Q000737:chemistry / Q000637:transplantation*; D002474:Cell-Free System; D005109:Extracellular Matrix / Q000737:chemistry*; D050723:Fractures, Bone / Q000473:pathology* / Q000628:therapy*; D006801:Humans; D006984:Hypertrophy; D045164:Mesenchymal Stem Cell Transplantation / Q000295:instrumentation*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D016062:Porosity; D023822:Tissue Engineering / Q000295:instrumentation / Q000379:methods; D054457:Tissue Scaffolds; D016896:Treatment Outcome
keywords: Decellularized scaffold; Endochondral ossification; Extracellular matrix; Hypertrophic cartilage; Large bone defect