Development of an animal-free methodology for mechanical performance assessment of engineered skin substitutes

Functional substitutes for the treatment of skin wounds are nowadays widely available thanks to the progress in skin tissue engineering. However, the performance of the existing substitutes in terms of mechanical behavior, which is a determinant for their success, still does not match the native tissue. Since the mechanical behavior of skin is governed by dermis, an in-depth investigation of human dermis mechanics would be pivotal for integrating the design and validation of skin substitutes. In the perspective of reducing and replacing animal experiments through validated alternative tools, an accurate in silico constitutive model describing the human dermis mechanics is presented. Biaxial tests were performed on human dermis samples, and resulting data were used for setting the constitutive parameters of the model, able to reliably describing the mechanical properties of the native tissue, and to be compared with the mechanical behavior of skin substitutes attainable through the same procedure.