Validation of a new 3D epidermis model for the SENS-IS assay to evaluate skin sensitization potency of chemicals

In vitro methods for evaluating skin sensitization are advancing as ethical alternatives to animal testing. The SENS-IS assay, based on genomic profiling, relies on robust biological models like 3D reconstructed human epidermis (RHE). The Rhe model from Episkin was typically used to performed the SENS-IS assay. This study validates the Skin+ model as an alternative to the established Episkin model in the SENS-IS assay. We tested 19 proficiency chemicals categorized by human and LLNA potency and compared results between Skin+ and Episkin. The Skin+ model demonstrated over 93 % intra- and inter-batch reproducibility, closely matching Episkin's performance. Additionally, barrier function tests and gene expression analyses confirmed the consistency of the Skin+ model in response to SLS, TNBS, and DMSO treatments. The Skin+ model proved to be a reliable and reproducible alternative to the EpiSkin model, maintaining strong barrier integrity and delivering comparable sensitization predictions. This validation broadens the options for laboratories and industries seeking versatile 3D RHE models for in vitro skin sensitization testing, supporting the transition to more ethical and precise methods.