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.