Corneal, Limbal, And Conjunctival Epithelium Of Bovine Eyes Imaged In Vitro By Using A Confocal Laser Scanning Microscope

Purpose: To provide a description of the distribution and cell morphology, by using fluorescent markers and confocal laser scanning microscopy, of the corneal, limbal, and conjunctival epithelium of bovine eyes in vitro.Methods: Fresh enucleated bovine eyes were dissected within 2 hours postmortem. Central cornea.. limbus, and bulbar conjunctiva were imaged with confocal microscopy after staining with acridine orange (AO) or calcein-acetoxymethyl and ethidium homodimer-1. Epithelial thickness, cell density, cell lamination, and cell morphology were evaluated at these 3 locations.Results: Corneal epithelium was the thickest, and the conjunctival epithelium was the thinnest. The cell morphology was similar to that found in previous histologic studies, and the cell density gradually decreased from the basal to superficial layers. Nuclear AO staining particles increased from basal to superficial cells. Limbal superficial epithelial cells showed less AO staining than corneal and conjunctival superficial cells.Conclusions: Confocal results of the corneal central, limbal, and conjunctival morphology are similar to those found in traditional microscopic observations. Bovine central corneal epithelium is thicker than limbal epithelium. However, the nuclear AO staining pattern of unfixed ocular surface epithelium of bovine eyes in vitro might represent the cell differentiation status. With the aid of the fluorescence dye, confocal laser scanning microscopy can provide unique morphometric information about corneal, limbal, and conjunctival epithelial cells.