Abstract
Background Large bone defects remain a major clinical challenge for orthopaedic surgeons. Tissue engineered bone grafts have garnered increased attention as a solution to this problem. One ideal property of any bone graft is osteoinductivity or the ability to stimulate progenitor cell differentiation into a bone forming lineage.
Questions
Is the osteoinductive potential of a porcine bone xenograft maintained in vitro after undergoing a novel decellularization and oxidation process?
Are porcine bone scaffolds osteoinductive in an in vivo animal model?
Methods
In Vitro – C2C12 pre-osteoblasts were seeded on the scaffold or a commercial grade demineralized bone matrix (DBM) to study osteogenic differentiation and compare osteoinductive potential. MC3T3-E1 pre-osteoblasts were seeded on the scaffold and compared to a control monolayer to identify early markers of osteogenic differentiation.
In Vivo – MC3T3-E1-seeded scaffolds were implanted subcutaneously in mice and assessed for markers of early osteogenic differentiation, new bone formation (micro-computed tomography and histological assessment), and vascular infiltration (histology).
Results Osteoinductive potential was demonstrated in in vitro experiments by similar osteogenic marker expression compared to DBM and significantly greater expression than a control monolayer.
Osteoinductivity was confirmed with in vivo experiments showing both new bone formation and vascular infiltration.
Conclusion Porcine bone maintains osteoinductive properties after decellularization and oxidation.
Clinical Relevance This construct could potentially serve as a bone graft substitute maintaining the osteoinductive potential of native bone. The unrestricted supply and controlled donor biology may satisfy a large clinical need for orthopaedic cases requiring bone grafting.