A modified trichrome stain for light microscopic examination of plastic-embedded corneal tissue.

Corneal histopathology is essential to understanding the mechanisms of corneal disease and wound healing. We have developed a light microscopic trichrome stain for 1-micron, aldehyde-fixed, osmicated, epon/resin-embedded corneal sections. The stain consists of azure II, methylene blue, and basic fuchsin. This combination of stains provides a fast and effective method to clearly differentiate corneal cells from their surrounding extracellular matrix, and chromatically separates various ECM materials within the cornea. Correlative examination by light and transmission electron microscopy (TEM) provides multilevel understanding of corneal morphology and ultrastructure. Tissues examined using this staining procedure may be subsequently examined by TEM for ultrastructural morphology. This stain has proved beneficial in our research of both cellular and extracellular constituents of the cornea.