The nasal respiratory epithelium in the human fetus: lectin histochemistry.

Lectin binding histochemistry was used to investigate the glycoconjugate saccharidic moieties in the respiratory epithelium of human fetuses ranging in age from the 8th to the 12th week of gestation. The distribution and changes in the sugar residues of the glycoconjugates at the level of the basal cells, the bathyprismatic cells and the bathyprismatic ciliated cells are reported. PNA and SBA allowed the identification of some 'elongated cells', which were characterized by lectin-reactive supranuclear granules. These epithelial cells, which have not previously been identified using conventional histochemical methods, might be the precursors of secretory cells.