Fragility of corneal epithelium induced by cornea-specific loss of plakoglobin in mice

Abstract

Purpose : To examine the role of plakoglobin in maintaining the integrity of corneal epithelium, we analyzed the cornea epithelium-specific plakoglobin (JUP) knockout mice and found keratin 14 was upregulated (Kokado et al, ARVO2016). Here we have tested whether the epithelial repair is impaired.

Methods : Cornea epithelium-specific conditional knockout (KO) mice were generated by breeding keratin12-Cre mice to JUP-floxed mice (Kokado et al, ARVO2016). Corneal epithelium of both normal control and KO mice were gently rubbed with a brush twice as previously reported (Kokado et al, IOVS 2013). Corneal tissues were collected and examined histologically under both light and transmission electron microscopies.

Results : We found that, while only the surface layer of the corneal epithelium was damaged by brush-rubbing in normal control mice, the subbasal and/or basal layers were evidently lost with the identical treatment in KO mice. However, the ultrastructure of the epithelial basement membrane did not appear to have any noticeable major abnormality in KO mice.

Conclusions : Our data further indicates that the corneal epithelium-deficient in plakoglobin has an enhanced sensitivity to brush-rubbing treatment. This finding confirms that plakoglobin is essential to the maintenance of the corneal epithelial integrity.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.