Ultrastructural comparative distribution of carbohydrates in human tracheal and frog palate mucosa using neuraminidase and lectin-colloidal gold complexes.
We have compared, at the ultrastructural level, the carbohydrate structure of glycoconjugates of the different types of secretory cells of the human tracheal mucosa (HTM) and the frog palate mucosa (FPM), proposed as a model for studying bacterial adherence to mucus-coated respiratory epithelium. In addition to reactivity with Concanavalin A and Lens cullinaris agglutinin, reactivity of Epon-embedded HTM and FPM secretory granules was studied by transmission electron microscopy using neuraminidase-gold complex and colloidal gold-adsorbed lectins with affinity for sugar residues of human mucins, namely the following: Helix pomatia, Lotus tetragonolobus, Ricinus communis II, Wheat germ and Limax flavus agglutinins. The affinity of HTM and FPM mucous and serous cells for the different colloidal-gold complexes was very similar, however Limax flavus agglutinin labelled only HTM and not FPM secretory granules. The FPM mucous and serous secretory granules were nevertheless intensely labelled by the neuraminidase-gold complex, demonstrating the presence of sialic acid residues. The close ultrastructural and histochemical similarities between HTM and FPM suggest that the FPM may be a valuable model for studying the specific interaction between microbial lectins and mucus glycoproteins in the bacterial adherence phenomenon.
Plotkowski
M C
MC
Serviço de Microbiologia e Immunologia, UERJ, Brazil.
Girod-Vaquez
S
S
Hinnrasky
J
J
Fuchey
C
C
Ploton
D
D
Puchelle
E
E
D000818:Animals; D001422:Bacterial Adhesion / Q000502:physiology; D050260:Carbohydrate Metabolism; D003102:Colloids; D006046:Gold; D006801:Humans; D037102:Lectins; D008854:Microscopy, Electron; D009061:Mouth Mucosa / Q000378:metabolism / Q000648:ultrastructure; D009092:Mucous Membrane / Q000378:metabolism / Q000382:microbiology / Q000648:ultrastructure; D009439:Neuraminidase; D010160:Palate, Soft / Q000378:metabolism* / Q000648:ultrastructure; D011893:Rana esculenta; D014018:Tissue Distribution; D014132:Trachea / Q000378:metabolism* / Q000648:ultrastructure
D003102:Colloids; D037102:Lectins; D006046:Gold; D009439:Neuraminidase