"Bioengineering a human face graft"
The “matrix of identity” is how the authors of the present study call a human face graft, a “new pathway in tissue engineering”. This new pathway is necessary, explain the researchers at the Catholic University Brussels (Belgium) and the University Hospital of Bern, Switzerland, because face allotransplantation – without doubt a “revolutionary reconstructive procedure” for severe disfigurements – is associated with the need for lifelong immunosuppression, which limits its usage.
The authors previously introduced a technique of matrix production of a porcine auricular subunit graft; in the present study, this technique was translated to a human face model.
Human fresh cadavers were used to procure 5 partial and 1 total face grafts. After arterial cannulation, the specimens were perfused with a combined detergent/polar solvent decellularization protocol. Preservation of vascular patency was assessed by imaging, cell and antigen removal by DNA quantification and histology. Lip scaffolds were cultivated with dermal, muscle progenitor and endothelial cells (on discs or in a bioreactor).
The authors report a successful decellularization in all facial grafts within 12 days, revealing acellular scaffolds with “full preservation of innate morphology”. In addition, imaging delivered proof that the entire vascular tree patency was preserved, while microscopic evaluation showed preservation of tissue structures as well as of major proteins.
In this study, the researchers managed to obtain complex acellular facial scaffolds while preserving a cell-friendly extracellular matrix and a perfusable vascular tree. The authors hope that this paper will support the further engineering of postmortem facial grafts.