[Preparation of porcine acellular dermal matrix by low concentration of trypsin digestion and repeated freeze-thaw cycles].

Objective: To establish a new method for the preparation of porcine acellular dermal matrix.

Methods: The antigenicity of the porcine dermis was weakened by removing epidermal and dermal cells from the porcine skin through the digestion with low-concentration trypsin and repeated freeze-thaw cycles. Split thickness porcine skin was treated with 0.05% trypsin to remove the cells from the epidermis and dermis. Repeated freeze-thaw cycles were employed to further weed out the residual cells within the dermis. The prepared acellular dermis was then examined grossly, as well as histologically, and also by immunohistochemical method.

Results: No cell could be identified in the prepared porcine acellular dermal matrix. The integral basement membrane was preserved on the surface of dermal matrix with compact dermal matrix collagen structure.

Conclusion: Low concentration trypsinization and repeated freeze-thaw cycles seemed to be a simple and effective method for the preparation of xenogeneic acellular dermal matrix.