title: Limb reconstruction with decellularized, non-demineralized bone in a young leporine model.
abstract: Limb salvage from a variety of pathological processes in children is often limited by the unavailability of optimal allograft bone, or an appropriate structural bone substitute. In this study, we sought to examine a practical alternative for pediatric limb repair, based on decellularized, non-demineralized bone grafts, and to determine whether controlled recellularization prior to implantation has any impact on outcome. Growing New Zealand rabbits (n = 12) with a complete, critical-size defect on the left tibiofibula were equally divided into two groups. One group received a decellularized, non-demineralized leporine tibiofibula graft. The other group received an equivalent graft seeded with mesenchymal stem cells labeled with green fluorescent protein (GFP), at a fixed density. Animals were euthanized at comparable time points 3-8 weeks post-implantation. Statistical analysis was by the Student t-test and Fisher's exact test (P < 0.05). There was no significant difference in the rate of non-union between the two groups, including on 3D micro-CT. Incorporated grafts achieved adequate axial bending rigidity, torsional rigidity, union yield and flexural strength, with no significant differences or unequal variances between the groups. Correspondingly, there were no significant differences in extracellular calcium levels, or alkaline phosphatase activity. Histology confirmed the presence of neobone in both groups, with GFP-positive cells in the recellularized grafts. It was shown that osseous grafts derived from decellularized, non-demineralized bone undergo adequate remodeling in vivo after the repair of critical-size limb defects in a growing leporine model, irrespective of subsequent recellularization. This methodology may become a practical alternative for pediatric limb reconstruction.
authors: Department of Surgery, Boston Children's Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
authors: Elliot C
authors: EC
authors: Pennington
authors: Beatrice
authors: B
authors: Dionigi
authors: Fabienne L
authors: FL
authors: Gray
authors: Azra
authors: A
authors: Ahmed
authors: Joseph
authors: J
authors: Brazzo
authors: Andrey
authors: A
authors: Dolinko
authors: Nathan
authors: N
authors: Calderon
authors: Thomas
authors: T
authors: Darrah
authors: David
authors: D
authors: Zurakowski
authors: Ara
authors: A
authors: Nazarian
authors: Brian
authors: B
authors: Snyder
authors: Dario O
authors: DO
authors: Fauza
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001696:Biomechanical Phenomena; D018786:Bone Substitutes; D016025:Bone Transplantation; D001842:Bone and Bones; D002118:Calcium / Q000378:metabolism; D005121:Extremities / Q000473:pathology / Q000502:physiology*; D005360:Fibula / Q000473:pathology*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology; D011817:Rabbits; D019651:Plastic Surgery Procedures; D013977:Tibia / Q000473:pathology*; D023822:Tissue Engineering / Q000379:methods; D014182:Transplantation, Autologous; D055114:X-Ray Microtomography
chemical_list: D018786:Bone Substitutes; D049452:Green Fluorescent Proteins; D000469:Alkaline Phosphatase; D002118:Calcium