Abstract
Purpose:
So far artificial tears have demonstrated a limited role in restoring ocular surface damage in dry eye syndrome. The aim of this study was to assess the efficacy of a new ocular surface modulator in an in vitro 3D model of human corneal epithelium damaged by severe osmotic stress and inflammation.
Methods:
A reconstructed human corneal epithelium (HCE) model challenged by the introduction of sorbitol in the culture medium for 16 hours was used to induce an inflammatory pathway and to impair the tight junctions integrity determining a severe modification of the superficial layer ultrastructure. The study was carried out in duplicate HCE in comparison to negative (standard HCE) and positive (stressed HCE) control. At the end of the overnight stress period in the study group 30ml of the ocular surface modulator (T-Lysyal, Sildeha, Switzerland) and of hyaluronic acid in the control group were applied for 24 hours. The following parameters were quantified :TEER (trans-epithelial-electrical-resistance), mRNA expression of ITGB1, CCND1,TNF-α, IL1- α. Immunofluorescence analysis by confocal microscopy for ITGB1 and scanning electron microscopy (SEM) of the epithelium were performed.
Results:
In the positive control after the osmotic stress the HCE surface damage was visible at ultrastructural level with loss of cell-cell interconnections and intercellular matrix destruction. The damage associated to the inflammatory pathway was confirmed by the overexpression of inflammatory and proliferation genes and by TEER reduction. After 24 hours of treatment the study group showed a significant improvement of the ultrastructural morphological organization of epithelium surface (SEM), increased expression of ITGB1, CCND1 mRNA when compared to baseline and control group (p<0.05). Decreased levels of TNF α were demonstrated compared to the control group (p<0.05).
Conclusions:
This study has shown for the first time that it is possible to modify epithelial cell damage and to control inflammation by using a modulator of the ocular surface. Further in vivo studies are certainly necessary to confirm these results.