REPRODUCIBILITY AND CORRELATION OF EPIOCULAR™, A THREE-DIMENSIONAL TISSUE CULTURE MODEL OF THE HUMAN CORNEAL EPITHELIUM.

The EpiOcular™ tissue model is an organotypic model of the human corneal epithelium (HCE) cultured from normal human keratinocytes using serum free medium. Paraffin embedded, H&E stained histology cross-sections show the structure of EpiOcular closely parallels that of the HCE; large nucleated basal cells lie beneath 5-6 stratified cell layers which progressively flatten out, ending with a highly squamous, non-keratinized layer at the culture’s apical surface. Over the first 11 months of commercial production, 52 lots of EpiOcular have been produced and monitored using the MTT assay. Exposure of a common surfactant, 0.3% Triton X-100, gave Effective Time-50 values (time of exposure after which viability is reduced to 50%, or ET-50) which had an average of 31.2 + 8.9 minutes (+ 1 standard deviation). In addition, ET-50 values were correlated to the Draize rabbit eye scores for 17 common chemicals from the ECETOC ocular irritancy data base and 13 final formulation shampoos and gave correlation coefficients, r, which were 0.937 and 0.856, respectively. Finally, release of the inflammatory mediators, interleukin 1-alpha (IL-1a) and prostaglandin E-2 (PGE-2), has also been observed following treatment of EpiOcular with mild surfactants such as Tween 20. These initial results provide the basis for further investigating the use of the EpiOcular tissue model to reduce and/or replace in vivo, animal-based ocular irritancy testing.

Basal cells, Beta-glucocerebrosidase, Chemicals, Corneal epithelium models, Cosmetic Personal Care Products, Shampoo(s), Draize prediction model, Draize scores, Draize tests, ET-50 Value, Endpoints, MTT, Endpoints, Prostaglandin E-2 (PGE-2), EpiOcular, Eye irritation, Inflammation, Inflammatory, Inflammatory mediators, MTT, MTT ET-50 tissue viability assay, MTT assay, Ocular irritancy testing, Ocular irritation, Ocular irritation testing, PGE-2, Pre-validation, Prediction model, Prevalidation, Prostaglandin E-2, Reproducibility, Reproducible, Surfactants, Surfactants, Triton X-100, Surfactants, Tween 20, Transdermal, Triton X-100, Tween, Validation, Viability