Immunohistochemical analysis of the pathogenesis of posterior polymorphous dystrophy
J. R. Ross, G. N. Foulks, F. P. Sanfilippo and D. N. Howell
Department of Ophthalmology, Veterans Affairs Medical Center, Baltimore, Md.
The pathogenesis of posterior polymorphous dystrophy was analyzed by
immunohistologic methods. Sections of corneal buttons from two patients
undergoing transplantation owing to posterior polymorphous dystrophy were
stained with 2B4.14.1, a monoclonal antibody that reacts with human corneal
endothelium, and with a cocktail of antihuman cytokeratin monoclonal
antibodies that do not react with normal corneal endothelium.
Single-stained sections revealed a variegated, intermittent staining
pattern of antibody reactive and nonreactive cells. Double-stained sections
revealed some cells that stained with only one of the antibodies and many
cells that stained with both antibodies. The presence of cells staining
positively for both 2B4.14.1 antigen and cytokeratins supports the
hypothesis that the cytokeratin-expressing epithelial-like cells found in
corneas with posterior polymorphous dystrophy arise via a metaplastic
process in which the phenotype of endothelial cells becomes progressively
abnormal.