LECTIN HISTOCHEMISTRY ON GLYCOCONJUGATES OF THE EPIDERMIS AND DERMAL GLANDS OF XENOPUS-LAEVIS (DAUDIN, 1802)

We performed an investigation at the light microscopical level of the differential distribution of lectin‐binding sites among cells of the epidermis and glandular domains of the African clawed frog Xenopus laevis. Using a panel of biotinylated lectins (Con‐A. PSA, LCA, UEA‐I, DBA, SBA, SJA, RCA‐I, BSL‐I, WGA, s‐WGA, PHA‐E and PHA‐L) and an avidin–biotin–peroxidase complex (ABC), we have identified specific binding patterns. The results show that expression of saccharide moieties in Xenopus epidermal keratinocytes is related to the stage of cellular differentiation, different cell layers expressing different sugar residues. Moreover, oliogosaccharides with “identical” biochemically defined sugar compositions can be distinguished. The method allowed further characterization of complex glycoconjugates of dermal glands. In view of these results, the ABC technique and the biotinylated lectins employed in the present study are believed to be a reliable method for the precise localization of saccharide residues of glycoconjugates present in ectothermic vertebrates. 1990 The Royal Swedish Academy of Sciences