Novel Animal Model of Limbal Stem Cell Deficiency Induced by Forcing Eye-Open at Birth

Abstract

The aim of this study was to develop a rat model of limbal stem cell deficiency (LSCD) by forcing eye-open at birth (FEOB).Methods: A total of 200 Sprague-Dawley neonatal rats were randomly divided into the control group and the experimental group, which received eyelid open surgery on postnatal day 1 (P1). Observation time points were defined as P1, P5, P10, P15, and P30. Slit-lamp microscope and corneal confocal microscope were used to observe the clinical features of the model. The eyeballs were collected for hematoxylin and eosin staining and periodic acid--Schiff staining. Proliferating cell nuclear antigen, CD68/ polymorphonuclear leukocytes, and cytokeratin 10/12/13 immunostaining were performed, while the ultrastructure of the cornea was observed by scanning electron microscopy. Real-time polymerase chain reactions (PCRs), western blot, and immunohistochemical staining of activin A receptor-like kinase-1/5 were used to analyze the possible pathogenesis.Results: FEOB could successfully induce the typical manifestations of LSCD, including corneal neovascularization, severe inflammation, and corneal opacity. In the FEOB group, goblet cells could be detected in the corneal epithelium by periodic acid-Schiff staining. The expression of cytokeratins was also different between the 2 groups. Furthermore, proliferating cell nuclear antigen immunohistochemical staining revealed the weak proliferation and differentiation ability of limbal epithelial stem cells in the FEOB group. Realtime PCRs, western blot, and immunohistochemical staining of activin A receptor-like kinase-1/activin A receptor-like kinase-5 in the FEOB group showed different expression patterns than those of the control group.Conclusions: FEOB in rats induces ocular surface changes resembling LSCD in humans, representing a novel model of LSCD.