BOVINE CORNEAL STROMA AND EPITHELIUM RECONSTRUCTED IN-VITRO - CHARACTERIZATION AND RESPONSE TO SURFACTANTS

In order to define safety profiles and proper handling procedures for new industrial products, it is essential to determine their potential for ocular irritation. The Draize test is normally employed but it inv olves using rabbits. There is today a great need for all researchers t o limit the use of animals for laboratory experiments and to encourage the development and adoption of alternative ill vitro methods to eval uate the potential toxicity of new products. This study proposes a thr ee-dimensional model of bovine corneal stroma and epithelium that is n ot only easy to reproduce but may also be used in the toxicological fi eld as an alternative to animal experimentation. The data presented he re show that this model allows the growth of epithelium similar in fea tures to in vivo epithelium. Basal cells are cube-shaped, whereas supe rficial areas are horizontally longer; desmosomes and 64 kDa keratin, as a marker for differentiation of corneal epithelial cells, are both expressed; the basal lamina is synthesised also. The -[4,5-dimethylthi azol-2-yl]2,5-diphenyltetrazolium bromide (MTT) assay was carried out on the model to evaluate the toxicity of some surfactants: benzalkoniu m chloride, Triton X-100, sodium dodecylsulphate and Tween 20. Since t he in vitro data fit very well the results of the Draize test in vivo as reported in the literature, the three-dimensional culture may be us ed to predict the potential cytotoxicity of surfactants.