CD-34 stromal expression pattern in normal and altered human corneas.

Abstract

To test CD-34 immunoreactivity in stromal cornea cells in normal and pathologic samples obtained from penetrating keratoplasty. Prospective, consecutive histopathologic human tissue study. One hundred two cornea buttons from patients with different diseases, submitted for cornea transplant, were examined. Controls were expired corneas from healthy donor patients who died (n = 4), and globes enucleated for primitive intraocular neoplasias, that is, retinoblastomas (n = 8), and malignant choroidal melanomas (n = 2). The expression of CD-34 in stromal cornea cells was examined by immunohistochemistry analysis. Other immunohistochemical stains included an endothelial cell marker (CD-31), common leukocyte antigen, and alpha-smooth muscle actin. Different diseases that may cause blindness and require penetrating keratoplasty have been tested for CD-34 immunoreactivity. In control corneas, keratocytes present strong and consistent CD-34 immunoreactivity. Diseases leading to the loss of transparency and penetrating keratoplasty, such as keratoconus, herpes keratitis, trauma, and heredofamilial dystrophies, are associated with focal or diffuse loss of CD-34 expression, whereas pseudophakic bullous keratopathy and Fuchs' endothelial dystrophy show normal CD-34 immunoreactivity in most cases and patchy unstained stromal areas in a few cases. Scar tissue formation in the cornea, as in herpes keratitis and trauma, is always associated with loss of CD-34 immunoreactivity, which may otherwise be a primary event in keratoconus and heredofamilial dystrophies. Both in the pseudophakic bullous keratopathy and Fuchs' endothelial dystrophy, CD-34 immunoreactivity may be normal or lost, hence these two diseases may be considered as one and part of the same group with regard to CD-34 expression, as revealed by immunohistochemistry analysis.