Browsing by Subject "Glycoconjugates"

Now showing 1 - 4 of 4
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    Characterization of glycoconjugates in the secretory epithelium of the equine ampulla ductus deferentis
    (Murcia : F. Hernández, 2008) Parillo, F.; Verini Supplizi, A.
    The present work was undertaken to determine the glycoconjugates secreted by the epithelium of the equine ampulla ductus deferentis, using conventional (PAS, AB pH 2.5, AB pH 1.0) and lectin histochemical procedures in conjunction with enzymatic digestion and chemical treatment. The presence of abundant apical cytoplasmic blebs suggests that the equine ampulla secretes its products mainly in an apocrine manner. Glandular cells secrete neutral and acidic sialylated glycoconjugates as revealed by conventional histochemical procedures. Lectin histochemistry helped us to discover the following histological positive sites: the mucosal cells, the glandular epithelial cells, the apical cytoplasmic blebs and the basal cells. The ampullary secretions contained both glycoproteic material (revealed by Con-A-, LCA-, GSA-II-, WGA-, RCA-I- positivity) and sialomucins (evidenced by the reactivity of GSA-II, SBA, PNA and RCA-I after sialidase digestion) having different functional roles. The mucosal cells reacted with Con-A, LCA, and also with sialidase/GSA-II-, SBA-, PNA-, and RCA-I sequences, contributing to the chemical heterogeneity of ampullary secretions. DBA lectin was a specific marker for basal cells. The results obtained were compared with our previous findings regarding the differences in the lectin binding pattern of the plasma-membrane of equine sperm collected from epididymal cauda and the ampulla ductis deferentis. Our results support other studies that indicate that ampullary secretions are involved in altering the plasma-membrane glycoconjugates of spermatozoa, contributing to their maturation.
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    Histochemical analysis of glycoconjugates in the domestic cat testis
    (Murcia : F. Hernández, 2006) Desantis, S.; Ventriglia, G.; Zubani, D.; Deflorio, M.; Megalofonou, P.; Acone, F.; Zarrilli, A.; Palmieri, G.; De Metrio, G.
    The localization and characterization of oligosaccharide sequences in the cat testis was investigated using 12 lectins in combination with the ßelimination reaction, N-Glycosidase F and sialidase digestion. Leydig cells expressed O-linked glycans with terminal aGalNAc (HPA reactivity) and N-glycans with terminal/internal aMan (Con A affinity). The basement membrane showed terminal Neu5Aca2,6Gal/GalNAc, Galß1,3GalNAc, a/ßGalNAc, and GlcNAc (SNA, PNA, HPA, SBA, GSA II reactivity) in O-linked oligosaccharides, terminal Galß1,4GlcNAc (RCA120 staining) and aMan in N-linked oligosaccharides; in addition, terminal Neu5Aca2,3Galß1,4GlcNac, Forssman pentasaccharide, aGal, aL-Fuc and internal GlcNAc (MAL II, DBA, GSA I-B4, UEA I, KOH-sialidase-WGA affinity) formed both O- and N-linked oligosaccharides. The Sertoli cells cytoplasm contained terminal Neu5Ac- Galß1,4GlcNAc, Neu5Ac-ßGalNAc as well as internal GlcNAc in O-linked glycans, aMan in N-linked glycoproteins and terminal Neu5Aca2,6Gal/ GalNAc in both O- and N-linked oligosaccharides. Spermatogonia exhibited cytoplasmic N-linked glycoproteins with aMan residues. The spermatocytes cytoplasm expressed terminal Neu5Aca2,3Galß1,4 GlcNAc and Galß1,3GalNAc in O-linked oligosaccharides, terminal Galß1,4GlcNAc and a/ßGalNAc in N-linked glycoconjugates. The Golgi region showed terminal Neu5aca2,3Galß1,4GlcNac, Galß1,4GlcNAc, Forssman pentasaccharide, and aGalNAc in O-linked oligosaccharides, aMan and terminal ßGal in N-linked oligosaccharides. The acrosomes of Golgi-phase spermatids expressed terminal Galß1,3GalNAc, Galß1,4GlcNAc, Forssmann pentasaccharide, a/ßGalNAc, aGal and internal GlcNAc in O-linked oligosaccharides, terminal a/ßGalNAc, aGal and terminal/internal aMan in N-linked glycoproteins. The acrosomes of cap-phase spermatids lacked internal Forssman pentasaccharide and aGal, while having increased a/ßGalNAc. The acrosomes of elongated spermatids did not show terminal Galß1,3GalNAc, displayed terminal Galß1,4GlcNAc and a/ßGalNAc in N-glycans and Neu5Ac-Galß1,3GalNAc in O-linked oligosaccharides.
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    Histochemical study of glycoconjugates in the toadfish Halobatrachus didactylus oesophagus epithelium
    (Murcia : F. Hernández, 2007) Desantis, S.; Cirillo, F.; Deflorio, M.; Megalofonou, P.; Palazón, J.L.; Sarasquete, C.; De Metrio, G.
    The carbohydrate expression in the epithelium lining the oesophagus of the toadfish Halobatrachus didactylus was studied by means of conventional and lectin histochemistry. The stratified epithelium was constituted by basal cells, polymorphous cells in the intermediate layer, pyramidal and flattened cells in the outer layer and contained two types of large secretory cells: goblet cells and sacciform cells. PAS, Alcian blue pH 2.5 and pH 1.0 stained very strongly the goblet cells, weakly the surface of the other epithelial cells but did not stain the sacciform cells. The goblet cells cytoplasm contained oligosaccharides with terminal Galß1,3GalNAc, a/ßGalNAc, Galß1,4GlcNAc, aL-Fuc and internal ßGlcNAc residues (PNA, SBA, RCA120, UEA I, LTA and KOH-sialidase-WGA affinity). Galß1,4GlcNAc, aL-Fuc and internal ßGlcNAc were also found in the glycocalyx. The sacciform cells expressed sialyloligosaccharides terminating with Neu5Aca2,3Galß1,4GlcNac, Neu5Acß2,6Gal/GalNAc, Neu5AcForssman pentasaccharide (MAL II, SNA, KOH-sialidase-DBA staining) as well as asialoglycoconjugates with terminal/internal aMan (Con A affinity) and with terminal Galß1,3GalNAc, Forssman pentasaccharide, Galß1,4GlcNAc, GalNAc (HPA and SBA reactivity), aGal (GSA I-B4 reactivity), D-GlcNAc (GSA II labelling), aL-Fuc. The basal cells cytoplasm exhibited terminal/internal aMan and terminal Neu5Aca2,6Gal/GalNAc, Galß1,4GlcNAc, a/ßGalNAc, aGal, GlcNAc, aL-Fuc. Intermediate cells showed oligosaccharides with terminal/internal aMan and/or terminating with Neu5Aca2,6Gal/GalNAc, Galß1,4GlcNAc in the cytoplasm and with Neu5Aca2,3Galß1,4GlcNac, a/ßGalNAc, aGal, GlcNAc, aL-Fuc in the glycocalyx. The pyramidal cells expressed terminal/internal aMan and terminal Neu5Aca2,6Gal/GalNAc, a/ßGalß1,4NAc, aGal, aLFuc in the entire cytoplasm, terminal Neu5Aca2,3 Galß1,4GlcNac and Forssman pentasaccharide in the apical extension, internal ßGlcNAc and/or terminal aLFuc in the luminal surface, Neu5aca2,3Galß1,4GlcNac, Neu5Aca2,6Gal/GalNAc, Galß1,4GlcNAc, aGal in the basolateral surface. The flattened cells displayed glycans with terminal/internal aMan and terminal Neu5Aca2,6Gal/GalNAc, a/ßGalNAc, aGal, DGlcNAc in the entire cytoplasm, glycans terminating with Galß1,3GalNAc and/or internal ßGlcNAc in the sub-nuclear cytoplasm.
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    lntermediate filament protein expression and sugar moieties in normal canine placenta
    (Murcia : F. Hernández, 2000) Fernandez, P.E.; Barbeito, C.G.; Portiansky, E.L.; Gimeno, E.J.
    In the female dog, the placenta is considered zonal, endotheliochorial and labyrinthic. The distribution of the intermediate filaments as well as the surface glycoproteins in the canine placenta are still unknown. The aim of the present study was to provide this information for further understanding of pathological conditions in the bitch. Samples were obtained from normal uterine horns at the end of gestation. Tissues were routinely fixed and stained. Monoclonal antibodies against cytokeratins, vimentin and desmin were used for immunohistochemical staining. UEA-1, PNA, RCA-1, SBA, DBA, WGA and ConA were used for the lectin histochemical staining. A computer morphometrical analysis was made. Statistical analysis was then accomplished. The results showed the maximun immunohistochemical percentage for vimentin in the supraglandular connective tissue, for pancytokeratin in the spongy zone and for desmin in miometrium. SBA showed the highest staining percentage in the gland cells of the spongy zone, while ConA was the highest in the syncytiotrophoblastic cells and gland cells of the deep glandular zone. The results obtained indicate that the lectin binding pattern is partially different from other animal species. On the contrary, the intermediate filament data coincide with similar observations from other mammals.