Purpose. Keratoconus is a disease characterized by thinning of the central and paracentral cornea and scarring in advanced cases. This study was performed to examine the expression of type XII collagen, proteins associated with hemidesmosomes, and β1 integrin in keratoconus corneas. Methods. Corneal buttons were collected from normal subjects and patients with keratoconus and other corneal diseases. Immunofluorescence staining was performed on frozen sections for type XII collagen, bullous pemphigoid antigen (BP180), and integrin subunits α6, β4, and β1. Results. To varying degrees, all proteins examined were expressed in normal human corneas. The staining intensity of type XII collagen was diminished in keratoconus corneas in the epithelial basement membrane zone and the stromal matrix. No significant variation was found in either the staining patterns or intensities for BP180, or integrins α6, β4, and β1. Conclusions. The level of type XII collagen was reduced in the epithelial basement membrane zone and stromal matrices in keratoconus corneas. These alterations may affect critical interactions of the corneal epithelium with the underlying basement membrane, and cell-matrix interactions and matrix organization in the stroma.
- Collagen type XII
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience