Trehalose protects corneal epithelial cells from death by drying.

AIM This study was designed to examine whether trehalose could protect corneal epithelial cells in culture from death by desiccation in order to test trehalose as a potential new eye drop for dry eye syndrome. METHODS Human corneal epithelial cells in near confluent culture in wells of a 96 well multidish were preincubated for 15 minutes with 2, 20, 50, 100, or 200 mM trehalose or maltose in phosphate buffered saline (PBS), PBS alone, or three kinds of commercially available artificial tear substitutes (one with borate buffered saline and the other two containing either hydroxyethylcellulose or hyaluronan). The medium was aspirated completely and cells were left dry for 30 minutes at room temperature in room humidity. Live cells and dead cells were visualised by fluorescent dyes and counted for statistical analysis. RESULTS The percentage of dead corneal epithelial cells after desiccation was significantly lower in preincubation with 50, 100, and 200 mM trehalose, compared with preincubation with PBS alone (p < 0.0001, Kruskal-Wallis test, and p < 0.05, Tukey-Kramer test). Trehalose at the concentration of 20 mM or lower, maltose at any concentrations, and commercially available artificial tear substitutes did not protect corneal epithelial cells from death by desiccation. CONCLUSIONS Trehalose at 50, 100, and 200 mM protected corneal epithelial cells in culture from death by desiccation. Trehalose could be used as a potential new eye drop for dry eye syndrome.