Conclusion
These data confirmed the strong potential of bioengineered constructs of stem cell-collagen scaffold for correcting large cranial defects in an animal model and highlighting the role of stem cells in neovascularization during skeletal defect reconstruction.
Methods
We performed two symmetric full-thickness cranial defects on each parietal region of rats and we replenished them with collagen scaffolds with or without stem cells already seeded into and addressed towards osteogenic lineage in vitro. After 4 and 8 weeks, cranial tissue samples were taken for histological and immunofluorescence analysis.
Results
We observed a new bone formation in all of the samples but the most relevant differences in defect correction were shown by stem cell-collagen samples 4 weeks after implant, suggesting a faster regeneration ability of the combined constructs. The presence of human cells in the newly formed bone was confirmed by confocal analysis with an antibody directed to a human mitochondrial protein. Furthermore, human cells were found to be an essential part of new vessel formation in the scaffold.