The use of the reconstructed Human Corneal Model (HCE) to assess in vitro eye irritancy of chemicals

The 7 amendment of the EU Cosmetic Directive will lead to the ban of animal testing for cosmetic ingredients in 2009 (acute tests). Many efforts have been made in order to find reliable and relevant alternatives methods to eye irritation testing. 3-D in vitro technology allows the evaluation of chemicals in conditions similar to in vivo use. In this study, we have used the SkinEthic Human Corneal Epithelial Model (HCE) to evaluate in vitro eye irritation potential of chemicals. Viability (MTT test) was used as the main endpoint to classify test-chemicals. The optimization of the in vitro protocol was based on a specific 60 min. contact time, adapted applied quantities (60 mg or 60μl/cm2) and a specific 16 hours post-treatment incubation period. A set of 102 chemicals belonging to different families, with known in vivo data was investigated in order to internally validate the protocol. The derived Predictive Model using a 50% viability cut off allowed the prediction of 2 classes: Irritants (R41 and R36 EU risk phrases) and Non Irritants (Non Classified). Performances were characterized by a good sensitivity (86%), a good specificity (83%) and good accuracy (84%). Results showed that the HCE model and the associated PM is a promising in vitro tool for the prediction of ocular irritancy.