[An immunohistochemical study on glycosaminoglycans distribution in the trabeculum of congenital aniridia]

Distribution of glycosaminoglycans in the trabecular tissue was immunohistochemically investigated in 7 congenital aniridia eyes of 5 patients aged 0 to 43 days. Paraffin sections of each specimen were immunohistochemically stained with antibodies to chondoroitin (clone 1-B-5), chondoroitin-1-sulfate (2-B-6), chondoroitin-6-sulfate (3-B-3), dermatan sulfate (6-B-6), and keratan sulfate (5-D-4). The trabecular meshwork and Schlemm's canal in all eyes were absent or not well differentiated. The cornea, trabecular tissue, and iris stroma were negative for chondoroitin immunostaining but positive for chondoroitin-4-sulfate, chondoroitin-6-sulfate, dermatan sulfate and keratan sulfate immunostaining. In the normal anterior segment tissue keratan sulfate is present in the cornea, trabecular tissue, and iris at the fetal stage, and disappears from the iris at the neonatal stage. These findings suggest that the persistence and/or abnormal distribution of keratan sulfate in the anterior segment may play a role in the pathogenesis of congenital aniridia.