The Expression and Distribution of MUC1 in Human Corneal Epithelium

ABSTRACT

Corneal and conjunctival squamous epithelial cells have been known to express the mucin MUC1. We attempted to reveal the expression and localizational characteristics of the membrane-spanning mucin MUC1 as a component of the mucous layer in the human corneal epithelium. An antibody to the MUC1 was used to detect the MUC1 on the corneal epithelium by immunohistochemistry and immunofluorescent staining. In situ hybridization was performed to determine the distribution of MUC1 mRNA in the ocular surface. Immunohistochemically, the MUC1 mucin was observed along the apical membranes of the corneal epithelium. According to immunofluorescent staining, cells varied in the amount of mucin MUC1. Expression of MUC1 mRNA was observed in all layers of the corneal epithelium. The MUC1 mucin synthesized by the corneal epithelia exists on the apical membrane of the superficial cells. The amount of MUC1 may vary with the vertical migration and the activity of the cells.