A Histochemical Study on Lectin Binding Patterns of Acquired Cholesteatoma Matrix

Lectins are non-immune origin proteins or glycoproteins binding to specific carbohydrates in the cell, which have been widely used as probes in cytochemical and oncogenic studies. The authors investigated the lectin binding. patterns of the human acquired cholesteatoma matrix and compared them to those of normal ear canal skin. Using an enzyme histochemical method with avidin-biotin-peroxidase complex(ABC), which is applicable to formalin-fixed paraffin-embedded tissue sections, the binding patterns of seven lectins were investigated ; concanavalin A(Con N, wheat germ agglutinin(WGN, Ricinus communis agglutinin(RCA-l), soybean agglutinin(SBA), peanut agglutinin(PNA), Ulex europaeus agglutinin(UEA-l) and Dolichos bifiorus agglutinin(DBN. The results observed under a light microscope were as follows : 1)The specificity of the lectin binding in cholesteatoma epithelium was confirmed in the control experiment. 2) SBA and UEA-l lectins did not show staining in the basal layer of the canal skin and tympanic membrane, but revealed positive staining in the basal layer of cholesteatoma. 3) DBA lectin showed negative staining in all 3 layers in both cholesteatoma and canal skin. From these results we can suggest that there is some altered carbohydrate specificity on the keratinocyte membrane of the chlolesteatoma that may lead to characteristic differentiation of cholesteatoma