Human and canine fucosidosis: a comparative lectin histochemistry study

Selected formalin-fixed, paraffin-embedded tissues of human and canine fucosidosis were stained with nine different lectins. Neurons, splenic sinusoidal cells, hepatic Kupffer cells, tissue macrophages, and capillary endothelium from human patients with fucosidosis stained intensely with Ulex europaeus agglutinin-I (UEA-I), but the same cells were unstained in tissues from canine fucosidosis. Since UEA-I specifically binds to terminal fucose residues, and fucose-rich undegraded metabolites are stored in affected cells of both human and canine fucosidosis, the variable lectin staining pattern demonstrates an unexpected species-specific histochemical variability. This finding highlights the fact that although both species have decreased fucosidase activity, the precursor substrates, undegraded stored metabolites, and particular cells affected by this enzyme deficiency are different.