BACKGROUND: Sialic acid residues are known to play a key role in the normal function of the glycoconjugates. Recently, with the development of specific sialic acid binding lectins such as Maackia seed agglutinin(MAA) and Sambucus nigra agglutinin(SNA), it has made easier to localize the sialic acid residues by the histochemical staining methods. OBJECTIVES: We were to observe the expression of sialic acids according to the differentiation of cultured human nasal epithelial cells by the immunohistochemistry method using Wheat germ agglutinin(WGA), MAA, and SNA. MATERIALS AND METHODS: Human nasal epithelial cell culture was done as floating method for the induction of differentiation. The cultured cells were fixed with 2.5% glutaraldehyde and the epon 812 was used as embedding material. The immunohistochemistry was done as Lim's method. RESULTS: The WGA and MAA positive reactions were noted from the floating zero day through the fourteenth day. The reactions were positive to the squamous-like cells and differentiating cells(ciliated and secretory epithelial cells). The WGA binding patterns were homogeneous but MAA binding patterns were inhomogeneous. The SNA positive reaction was noted only in the fourteenth day and the reaction was inhomogeneous. These results meant that N-acetyl glucosamine and N-acetyl neuraminic acid(alpha 2,3) galactose were expressed from the floating zero day and N-acetyl neuraminic acid(alpha 2,6) galactose was expressed from the floating fourteenth day. CONCLUSION: N-acetyl neuraminic acid(alpha 2,3) galactose may be more important to the primary defence of human nasal epithelial cell. Due to the inhomogeneity of the reaction, the further study using Lowicryl K4M will be needed.
Cells, Cultured ; Epithelial Cells* ; Galactose ; Glucosamine ; Glutaral ; Glycoconjugates ; Humans* ; Immunohistochemistry ; Lectins ; Maackia ; N-Acetylneuraminic Acid* ; Sambucus nigra ; Sialic Acids* ; Triticum

This study was conducted in order to observe ultrastructural changes in the expression of sialoglycoconjugates in maxillary sinus mucosa after inoculation of influenza A virus utilizing four different gold-labeled lectins : ckia amurensis (MAA), wheat germ agglutinin (WGA), sambucus nigra (SNA), and peanut agglutinin (PNA). A comparison of the affinities of these gold-labeled lectins demonstrated the varying distributions of sialoglycoconjugates in the ciliary layer and the granules in goblet cells. Examination of normal sinus mucosa labeled with four gold-labeled lectins showed the distribution of sialoglycoconjugates to be mainly in the ciliary layer and the granules in goblet cells and restricted to the surface of the cilia, microvilli and the secretory light granules. The application of an influenza A virus infection decreased the labeling intensity of gold-labeled MAA in the cilia and the secretory granules but not of WGA. SNA gold did not label the surface of the cilia and granules in either case. PNA gold particles, however, labeled the cilia and the secretory granules very weakly in normal sinus mucosa, but labeled moderately in cases of influenza A virus infection. These results suggest that the sugar residues of sialoglycoconjugates consist of Neu5Ac(alpha2, 3)Gal, GlcNAc, Neu5Ac. They also suggest that the sugar residues serve as a protecting factor or modulator against influenza A virus infection.
Cilia ; Goblet Cells ; Influenza A virus* ; Influenza, Human* ; Lectins ; Maxillary Sinus ; Microvilli ; Mucous Membrane* ; Peanut Agglutinin ; Rabbits* ; Sambucus nigra ; Secretory Vesicles ; Triticum

Reports of influenza A virus infections in dogs has received considerable attention from veterinarians, virologists, and epidemiologists. Interaction between influenza viral hemagglutinin and cell oligosaccharides containing sialic acid residues results in infection. Sialic acids have an alpha-2,3-linkage to the penultimate galactose in the avian influenza virus receptor and an alpha-2,6-linkage in the human receptor. To date, there are no detailed data on the tissue distribution or histological features of either type of sialic acid-linked influenza virus receptors in beagle dogs, which are common laboratory animals and pets. We conducted the current study to visualize the in situ tissue distribution of both sialic acid-linked influenza virus receptors in various organs of beagle dogs using Maackia amurensis lectin II and Sambucus nigra agglutinin. Both alpha-2,3- and alpha-2,6-sialic acid-linked receptors were detected in the endothelial cells of the respiratory tract and other organs. Endothelial cells of most gastrointestinal organs were negative for alpha-2,3-sialic acid-linked receptors in the dogs. Our results suggested that these canine organs may be affected by influenza virus infection. The findings from our study will also help evaluate the occurrence and development of influenza virus infections in dogs.
Animals ; Dog Diseases/metabolism ; Dogs/metabolism/*virology ; Female ; Influenza A Virus, H5N1 Subtype/*metabolism ; Maackia/chemistry ; Male ; N-Acetylneuraminic Acid/metabolism ; Organ Specificity ; Orthomyxoviridae Infections/metabolism/transmission/veterinary ; Plant Lectins/metabolism ; Receptors, Cell Surface/analysis/chemistry/metabolism ; Receptors, Virus/analysis/chemistry/*metabolism ; Sambucus nigra/chemistry