Inducing Dry Eye Disease Model

The DES model was induced as described by Liu et al. by topical application of 5 μL of 0.2% BAK (B6295; Sigma Aldrich, France) or PBS as a control twice a day for 10 days [23 (link)]. Topical BAK treatment induces an ocular surface injury with a decrease of CGC, a component of disease mechanism that leads to dry eye. Preliminary experiments showed that the decrease of CGC density after 10 days of BAK treatment is still observed by pCLE after 4 days without any treatment following the 10-day time course of topical BAK application, leaving a 4-day window time period to test a drug treatment. To stimulate CGC differentiation, topical administration of IL13 was administrated. Based on published data on topical application of IL28A [24 (link)] and preliminary data obtained in our laboratory on rIL13 in mice with DES, we used five ng of rIL13 (5 μL; SRP4166; Sigma Aldrich, France) that were administered by topical application twice a day for four days.