Epithelial cell adhesion molecule‐1 (ECAM1) is required in the maintenance of corneal epithelial barrier integrity

Abstract

Corneal epithelial barrier integrity is critical in the maintenance of the corneal homeostasis. The corneal barrier dysfunction may be associated with the pathogenesis of a number of eye diseases. In this study, we assessed the expression of epithelial cell adhesion molecule-1 (ECAM1) in human corneal epithelial cells (HCE). The epithelial barrier function of the corneal epithelial monolayer was determined in Transwells. We found that the HCE cells expressed ECAM1. Knockdown of ECAM1 markedly compromised the HCE monolayer barrier function. A complex of ECAM1, claudin1, and occludin was detected in the HCE monolayers, which was not detected in the ECAM1-null HCE monolayers. Exposure to the proinflammatory cytokine, interleukin-13, inhibited the expression of ECAM1 in HCE cells and compromised the barrier function, which was prevented in the HCE monolayer with the ECAM1 overexpression. In conclusion, ECAM1 is required in the formation of the tight junction complex and maintaining the corneal epithelial barrier function.