We investigated the binding of five HRP-conjugated lectins to
rabbit tooth germs at the cap and late bell stages of development. The results
revealed some changes in the glycosylation patterns of the glycoconjugates.
Sugar residues, such as a-D-mannose, methyl-D-glucose, N-acetylglucosamine,
P-D-galactosamine, D-galactose, and sialic acid, were detectable in some components
of the tooth germs. The most conspicuous developmental change was
increased binding of Con A and WGA. These lectins showed, at the cap stage,
moderate binding to the (pre)-ameloblasts and (pre)-odontoblasts. With further
development to the late bell stage, but prior to the achievement of
well-defined morphological-functional characteristics, the odontoblasts and
ameloblasts displayed considerable amounts of a-D-mannose, a-D-glucose as
well as p-D-acetylglucosamine and siahc acid. Appropriate control studies confirmed
the specificity of the binding of the lectins. Two lectins (DBA and PNA) with known
specificity for N-acetylgalactosamine groups were bound by the basement membranes
in tooth germs at the cap stage. A third lectin (RCA) with the same specificity
did not produce any detectable staining in the same material. Further studies must
be planned to determine the specific functions and significance of ledin-HRPbinding
glycoconjugates in odontogenesis