A step towards an artificial skin: a novel supermacroporous anisotropic cryogel for wound healing applications

Objectives: Various artificial skin products are available to the surgeon; however they are not used extensively in the clinic, mainly due to their low efficiency or high cost. To address these limitations we have produced a novel supermacroporous gelatine cryogel scaffold with a highly sophisticated ordered anisotropic pore structure. The material was characterized and assessed in vitro for its skin substitution potential. Methods: The cryogel was characterized morphologically by confocal laser scanning and scanning electron microscopy. The dynamic elasticity and viscosity were assessed to characterize its mechanical properties. The cryogel was seeded with primary human fibroblasts or keratinocytes to assess its cytotoxicity and biocompatibility. The rates of cellular migration, proliferation and protein deposition were assessed immunohistochemically over a 28-day period. Keratinocytes were also seeded onto the cryogel scaffold to assess the ability to form a bilayered artificial skin. The performances of a gelatin cryogel were compared with those of a commercially available dermal regeneration template, Integra®. Results: The gelatin cryogel scaffold demonstrated a supermacroporous, highly sophisticated, ordered, anisotropic pore structure. The material was mechanically similar to Integra®. The cryogel was found to be biocompatible and non-toxic to human skin cells, supporting active cellular migration and proliferation. The keratinocytes formed a continuous differentiated layer on the surface of the gelatine cryogel scaffold, mimicking the native skin bilayered structure. Conclusions: The large size of interconnected gradient pores, biocompatibility and small production costs of gelatine cryogels make them a promising material for tissue engineering and regenerative medicine, to treat burns and chronic wounds.