Mast Cell Chymase Decreases the Barrier Function and Inhibits the Migration of Corneal Epithelial Cells

PURPOSE: We investigated the in vitro effects of human mast cell chymase on corneal epithelial cells. METHODS: Human corneal epithelial cells were incubated with human chymase at activity levels that were likely to exist in the tears of patients with vernal keratoconjunctivitis. RESULTS: Incubation of chymase resulted in a decrease of barrier function of corneal epithelium. Occludin protein was cleaved by chymase. In the wound assay, incubation with chymase resulted in an inhibition of cell migration. CONCLUSION: Human chymase causes the proteolysis of occludin and fibronectin, resulting in a decrease of barrier function and inhibition of the migration of corneal epithelial cells.