Changes in the localization of collagens IV and VIII in corneas obtained from patients with posterior polymorphous corneal dystrophy
Abstract
The aim of this study was to determine the changes in the presence and localization of the α1 – α6 collagen IV and α1, α2 collagen VIII chains in Czech patients with posterior polymorphous corneal dystrophy (PPCD). Twelve corneal buttons from ten PPCD patients as well as eight control corneas were used and enzymatic indirect immunohistochemistry was performed.
More than 50% of PPCD specimens exhibited positivity for α1 and α2 collagen IV chains in the basal membrane of the epithelium and in the posterior stroma, while no staining was detected in controls. The α1 collagen VIII chain was detected on the endothelial and stromal sides of Descemet’s membrane (DM), compared with the prevailing localization on the stromal side of DM in control corneas.
The increased expression and the change in localization of the α1, α2 collagen IV and α1 collagen VIII chains may contribute to the increased endothelial proliferative capacity observed in PPCD patients.