Abstract
Purpose :
We previously reported that Rebamipide (Mucosta® Otsuka Pharmaceutical Co., Ltd, Tokyo) accelerated the stratification of cultivated human conjunctival epithelial sheet due to the increased cell proliferation and enhanced the barrier function of the conjunctival epithelium (2014 ARVO). In this study, we investigated the mechanism of barrier function enhancement.
Methods :
Human limbal conjunctival tissues from donor corneas were cultured for two weeks to prepare the stratified conjunctival epithelial sheets. Rebamipide (5μM and 20μM) was added to the culture medium for the last four days of cultivation. Expression of the tight junction protein zonular occludens (ZO) 1, which was enhanced in the immunostaining of the stratified human conjunctival epithelial sheet, was confirmed using RT-PCR and Westen blot analysis.
Results :
Gene expression of ZO-1 was upregulated under culture condition harboring Rebamipide 20μM, with enhancement of the barrier function. However, in Western blot analysis, obvious differences in the expression of ZO-1 protein for each culture condition were not observed.
Conclusions :
A divergent ZO-1 expression pattern between gene and protein was observed. Expression level of ZO-1 protein in Western blot analysis was similar in each condition. However, in the more stratified cultivated human conjunctival epithelial sheet in presence of 20μM Rebamipide, not only an enhancement of ZO-1 expression in the superficial layers, but also an increase of ZO-1 negative cells in the lower layers were observed. Therefore, we conclude that the amount of ZO-1 protein is increased by rebamipide, which also enhanced the barrier function of the conjunctival epithelium.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.