Face Graft Scaffold Production in a Rat Model.

Background: As a route toward face bioengineering, the authors previously reported the production of a complete scaffold by perfusion-decellularization of a porcine ear subunit graft and partial recellularization. To extend the scaffold to the whole face and to down-scale it, they applied their findings to a rodent hemifacial graft model.

Methods: After the animals were killed, seven full-thickness rat hemiface grafts were harvested with the common carotid artery and the external jugular vein as a pedicle, and cannulated. Grafts were decellularized by a detergent-based protocol: either by perfusion through the common carotid artery, or by mechanical agitation. After decellularization, samples were analyzed for DNA quantification and histology by hematoxylin and eosin, Masson trichrome, Sirius red, or Safranin O staining. Vascular tree patency was assessed by microangiographic computed tomography after contrast injection. Cell-friendly extracellular matrix was assessed by seeding of human adipose-derived stem cells and vital staining after 7 days of culture.

Results: Decellularization was effective in both groups, with a cell clearance at all levels, with the exception of cartilage areas in the agitation-treated groups. Microscopic assessment found a well-preserved extracellular matrix in both groups. Vascular contrast was found in all regions of the scaffolds. After the animals were killed, seeded cells were found viable and well distributed on all scaffolds.

Conclusions: The authors successfully decellularized face grafts in a rodent model, with a preserved vascular tree. Perfusion-decellularization led to better and faster results compared with mechanical agitation but is not mandatory in this model. The rat face is an interesting scaffold model for further recellularization studies, in the final goal of human face bioengineering.