Abstract
To evaluate the protective function of the mucous blanket (MB) against lectin substances, we examined at the ultrastructural level whether intraluminal colloidal gold-labelled wheat germ agglutinin (WGA) could enter the MB-covered epithelial cell surface of the guinea pig tubotympanic mucosa. Post-embedding staining with WGA/gold on thin tissue sections was done in parallel for comparison. The cell surface glycoconjugate of the eustachian tubal and transitional epithelium had a typical bilayered structure: the outer MB and the microvilli-associated glycocalyx (MAG), which were interposed by the interciliary fluid zone. In squamous epithelium of the distal middle ear, the MB adhered to the MAG, thereby forming a monolayered coat of glycoconjugates at the cell surface. In the pre-embedding staining, WGA/gold did not bind with the MB and MAG in the eustachian tube, and exclusively bound with MB in the transitional area. Direct binding was also found with MAG and the apical plasmic membrane in the squamous epithelium. These findings indicate that MAG is occluded by MB lined with the interciliary fluid zone for luminal access of lectin at the proximal lumina of the tubotympanic epithelium. It is also suggested that MB existing at two sites possesses a different WGA-binding capacity: shielding as a “dust cover” in the eustachian tube and entrapping as a “flypaper” against lectin in the transitional area of the middle ear.
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References
Allen A, Neuberger A, Sharon N (1973) The purification, composition and specificity of wheat-germ agglutinin. Biochem J 131:155–162
Beachey E (1981) Bacterial adherence: adhesin-receptor interactions mediating the attachment of bacteria to mucosal surfaces. J Infect Dis 143:325–345
Carlemalm E, Garavito R, Villiger W (1982) Resin development for electron microscopy and an analysis of embedding at low temperature. J Microbiol 126:123–143
Frens G (1973) Controlled nucleation for the regulation of the particle size in monodisperse gold solution. Nature 241:20–22
Geoghegan W, Ackermann G (1977) Adsorption of horseradish peroxidase, ovomucoid and anti-immunoglobulin to colloidal gold for the indirect detection of Concanavalin A, wheat germ agglutinin and goat anti-human immunoglobulin G on cell surfaces at the electron microscopic level: a new technique, theory and application. J Histochem Cytochem 25:1187–1200
Green G, Jakab G, Low R, Davis G (1977) Defense mechanisms of the respiratory membrane. Am Rev Respir Dis 115:479–514
Horisberger M (1984) Lectin cytochemistry. In: Polak J, Varndell I (eds) Immunolabeling for electron microscopy. Elsevier, Amsterdam, pp 249–258
Inagaki M, Sakakura Y, Shimizu T, Majima Y, Kotaro U (1988) Ultrastructure of the blanket in otitis media with effusion. Ann Otol Rhinol Laryngol 97:313–317
Lim D (1987) Middle ear and inner ear structure and biological function. In: Bernstein J, Ogra P (eds) Immunology of the ear. Raven Press, New York, pp 1–37
Lim D, Paparella M (1967) Ultrastructure of the eustachian tube and middle ear mucosa in the guinea pig. Acta Otolaryngol(Stockh) 63:425–444
Morioka H, Tachibana M, Suganuma A (1987) Ultrastructural localization of carbohydrates on thin section of Staphylococcus aureus with silver methenamine and wheat germ agglutiningold complexes. J Bacteriol 169:1358–1362
Ofek I, Sharon N (1990) Adhesins as lectins: specificity and role in infection. In: Jann K, Jann B (eds) Bacterial adhesins. Springer, Berlin Heidelberg New York, pp 91–113
Roth J (1983) Application of lectin-gold complex for electron microscopic localization of glycoconjugates on thin section. J Histochem Cytochem 31:987–999
Sakakura Y, Ukai K, Majima Y, Murai S, Harada T, Miyoshi Y (1983) Nasal mucociliary clearance under various conditions. Acta Otolaryngol (Stockh) 96:167–173
Sharon N (1986) Bacterial lectins. In: Liener I, Sharon N, Goldstein I (eds) The lectins. Academic Press, Orlando, pp 494–526
Takasaka T, Kawamoto K (1985) Mucociliary dysfunction in experimental otitis media with effusion. Am J Otolaryngol 6:232–236
Tanimura F, Morioka H, Tachibana M (1987) Glycoconjugates in the glycocalyx of the guinea pig middle ear mucosa as revealed by post-embedding staining with lectin-gold complexes. Acta Histochem Cytochem 20:315–320
Tanimura F, Morioka H, Tachibana M (1987) Glycoconjugates of secretory granules in the middle ear mucosa as revealed by post-embedding staining with lectin-gold complexes. Acta Histochem Cytochem 20:621–628
Tanimura F, Tachibana M, Morioka H, Mizukoshi O (1988) Glycoconjugates in the guinea pig middle ear mucosa as revealed by postembedding staining with lectin-gold complexes. In: Ohyama M, Muramatsu T (eds) Glycoconjugates in medicine. Professional Postgraduate Services, Tokyo, pp 328–332
Tanimura F, Morioka H, Murakami Y (1990) Glycoconjugate histochemistry in the glycocalyx of guinea pig middle ear mucosa. Eur Arch Otorhinolaryngol 247:291–295
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Tanimura, F., Morioka, H. & Murakami, Y. Cell-surface glycoconjugate layer in the tubotympanic mucosa of the guinea pig as revealed by wheat germ agglutinin/gold labelling. Eur Arch Otorhinolaryngol 252, 249–254 (1995). https://doi.org/10.1007/BF00179920
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DOI: https://doi.org/10.1007/BF00179920