EXPRESSION OF A MUCIN-LIKE GLYCOPROTEIN PRODUCED BY OCULAR SURFACE EPITHELIUM IN NORMAL AND KERATINIZED CELLS

PURPOSE: We previously characterized a mono clonal antibody (H185) to a mucin-like glycoprotein produced by human ocular surface epithelium. In the current study, we used H185 to investigate the pattern of the mucin-like glycoprotein in normal and keratinized apical cells of the ocular surface epithelium. METHODS: We compared the cell characteristi cs and the pattern of H185 binding in cytologically and immunohistoche mically stained samples of apical cells of conjunctival surface epithe lium from 20 normal subjects and six patients before and after treatme nt for superior limbic keratoconjunctivitis. RESULTS: In the superior bulbar conjunctiva of normal subjects, the intensity with which H185 a ntibody bound to apical surface epithelial cells varied, with areas of high, medium, and low-intensity binding occurring in a mosaic pattern . This mosaic pattern, and presumably expression of the mucin-like gly coprotein, was absent or re markably reduced in keratinized cells obta ined from patients with superior limbic keratoconjunctivitis before tr eatment. However, the pattern of H185 binding was normal in samples ob tained 2 months after the start of treatment for superior limbic kerat oconjunctivitis, and cells had recovered their normal small, round app earance. CONCLUSION: When they are keratinized, api cal cells of the o cular surface epithelium are altered in appearance and lack the normal mosaic pattern of expression of a mucin like glycoprotein.