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
