EPIRETINAL MEMBRANE OF PROLIFERATIVE DIABETIC-RETINOPATHY - AN IMMUNOHISTOCHEMICAL STUDY

Nineteen cases of epiretinal membrane (ERM) in proliferative diabetic retinopathy were studied using immunohistochemical methods. Antibodies against type I-IV collagen, fibronectin tin (FN), glial fibrillary ac idic protein (GFAP), vimentin and the monoclonal antibody (MAB) agains t human Muller cells were used to examine the membranes. Type II colla gen was found on one side of the ERMs in 95 % of the cases. The other types of collagen, FN and vimentin were also identified in most cases. Muller cells (GFAP- and MAB-positive) were found in 2/19 cases(11%), and astrocytes (GFAP-positive but MAB-negative) were found in 10/19 ca ses (53%). These results suggest that type II collagen (vitreal collag en) may act as a scaffolding in the formation of ERMs and that glial e lements of the ERMs consist mainly of astrocytes.