In recent times, with the need for a reduction, refinement, and replacement of in
vivo animal testing, there has been an increasing demand for the use of relevant in
vitro human cell systems in drug development. There is also a great demand for the
replacement of skin tissue in various wounds and burns. Furthermore, human skin cell-based
in vitro systems can be used to investigate the side effects (toxicity and irritation)
and tissue penetration of topical preparations. In this study, exploratory experiments
were performed to produce artificial epidermis using two hydrogel scaffolds, alginate
and GelMA C. The amount of keratinocytes added to the matrix (10–50–100 × 106/mL)
and the duration of tissue maturation (fresh, 1–3–4 weeks) were optimized in an extensive
study. The behavior and structure of the two hydrogels were functionally and morphologically
assessed. The permeability order for caffeine in the tested barriers was the following:
alginate > GelMA C > cellulose acetate membrane > rat skin. It was concluded that
GelMA C matrix provides a more favorable environment for cell survival and tissue
differentiation (as demonstrated by histology and immunohistochemistry) than alginate.
The 3-week incubation and 50 × 106/mL cell number proved to be the most beneficial
in the given system. This study provides data for the first time on the multifactorial
optimization of two potential skin substitutes for tissue manufacturing. In order
to use these results in tissue engineering, the fabricated artificial epidermis preparations
must also be optimized for biocompatibility and from physical and mechanical point
of views.
