Schmidt, R., C. Duval, and M. Regnier. Reconstructed Human Skin: Alternative Models for the Safety and Efficacy Assessment of Dermato-Cosmetological Products. ATLA 1999. 27: 81.

Models of reconstructed human skin provide useful tools, not only in basic research to better understand the mechanisms of keratinocyte differentiation and the complex mechanisms of cell-cell interaction, but also in the safety and efficacy assessment of new dermato-cosmetological products. They can provide alternative models to replace human and animal experiments. The fact that the epidermis in most of the existing reconstructed skin models is composed of keratinocytes only excludes their use in the field of skin pigmentation and immunology. Nevertheless, these models have been used successfully as alternative models to assess the efficacy and safety of products. We have recently succeeded in integrating Langerhans cells into a pigmented reconstructed epidermis. Using melanocytes of different racial origin, we are able to reproduce in vitro the various phenotypes of skin pigmentation. Pigmented reconstructed human epidermis provided an excellent means in our research efforts to identify new modulators of melanogenesis to develop cures and corrections to pigment related disorders. The presence of Langerhans cells in the epidermal reconstructs will eventually enable us to study the role of these cells in the skin immune system. We are evaluating this reconstructed skin model for its use in predicting the skin sensitization potential of new dermato-cosmetic compounds and to investigate the role of Langerhans cells in UV-induced immunosuppression.