Assessment of the SkinEthic® Reconstituted Human Epidermal model for the prediction of the dermal irritation potential of chemicals

During the past ten years, a lot of attention has been paid to the development of in vitro tests that could substitute irritation studies employing animals. The best results were until now obtained with 3D reconstructed human skin equivalents, for which several test protocols have been developed.In areas of skin corrosion and photo-toxicity, it has been proven that similarities between well developed 3D skin models allowto use common test protocols, obtaining similar results. Recently, efforts have been undertaken to develop a common protocol for the assessment of skin irritation of chemicals using skin models. This "common skin irritation protocol" for EPISKIN? and EpiDermTM reconstructed epidermal models is currently evaluated in an ECVAM validation study.Concurrently with the ECVAM skin irritation validation study, ZEBET (Berlin, Germany) performed a small scale study applying the "common skin irritation protocol" on SkinEthic? Reconstructed Human Epidermis (RHE) to verify whether this protocol can be successfully transferred to another epidermal model. Twenty substances from the ECVAM pre-validation study on skin irritation were tested on SkinEthic RHE. After minimal model specific adaptations, almost identical results (when compared to results of EpiDerm and EPISKIN models) were obtained.Then the protocol's transferability was evaluated at ZEBET and SCHERING AG (Berlin, Germany) by testing six coded chemicals in three independent runs, obtaining very good results. In addition, an analysis of IL 1-? release was performed, with the aim to investigate if a second endpoint could add valuable information for the prediction of skin irritation potential of chemicals.