Development of a novel Reconstructed human Cornea-like Epithelium (RhCE) model for testing ocular irritation in vitro

During medical device development, ensuring non-irritancy is mandatory. To replace animal experimentation and to address limitations of traditional monolayer cell cultures, three-dimensional tissue models are used. This project aimed to develop a novel Reconstructed human Corneal Epithelium model (RhCE) to be used to assess ocular irritation. According to OECD Test Guideline n°492 on RhCEs as tools chemicals evaluating irritancy, a novel RhCE model must be functionally characterized in terms of viability, barrier function, morphology and reproducibility. A novel RhCE model was defined using immortalized human primary corneal epithelial cell line grown on porous synthetic inserts under air liquid interface (ALI). Viability was verified by MTT assay. Histological analysis showed that ALI exposure led to the formation of a multilayer tissue, with thickness proportional to ALI exposure time. Barrier integrity was monitored by recording Trans Epithelial Electrical Resistance, as well as estimation of half-maximal inhibitory concentration (IC50) of sodium dodecyl sulfate indicated that early and prolonged ALI exposure enhanced barrier function. The results also suggested that early ALI exposure, lasting for an additional 4 to 7 days would be optimal to fulfill the functional requirements outlined in the guideline. Future work will focus on optimizing and validating the presented model.