Browsing by Subject "Lectins"
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- PublicationOpen AccessCarbohydrates and soluble lectins in the regulation of cell adhesion and proliferation(Murcia : F. Hernández, 1994) Zanetta, J.P.; Badache, A.; Maschke, S.; Marschal, P.; Kuchler, S.There is a large body of suggestions that complex carbohydrates play a role in the regulation of cell adhesion and cell proliferation. Many reports have emphasized that proteoglycans. glycoproteins or glycolipids are participating to cell adhesion mechanisms. The use of polyvalent anti-carbohydrate antibodies and plant lectins as well as the use of glycosy lation inhibitors suggested that cell proliferation can be nlodulated by surface carbohydrates. The dating experiment of Burger and Noonan (1970) showing restoration of contact inhibition of malignant cells by monovalent concanavalin A was a determining experiment. However, in the latter as in the others, no precise mechanism was demonstrated how carbohydrates can be involved in adhesion and proliferation. New insights were opened with the discovery of vertrebrate membrane-bound and soluble lectins. The latter generally display agglutinating activities in in vitro systems, suggesting that they were potential cell adhesion molecules, by forming bridges between cell surface carbohydrates. These polyvalent molecules may be also considered as clustering agents for their cell surface ligands, conseq~~entlgye nerating signals for cell proliferation andlor differentiation.
- PublicationOpen AccessCharacterisation of cytotrophoblastic-like cells present in subinvolutioned placental sites of the bitch(Murcia : F. Hernández, 1998) Fernandez, P.E.; Portiansky, E.L.; Barbeito, C.G.; Gimeno, E.J.This paper describes an approach to study the cells present in the subinvolution of placental sites (SIPS), a pathological post partum condition of the bitch that causes persistent hemorrhage of the genital tract. The expression of intermediate filament proteins was examined to determine the fetal or maternal origin of the cytotrophoblastic-like cells found in this entity. Lectin binding on tissue sections were also studied to characterise cellular glycoconjugates. Image processing and morphometrical analysis of the histological images were done. The results revealed that the cells observed in bitches with SIPS expressed pancytokeratins but neither vimentin nor desmin, in coincidence with normal cytotrophoblasts. The lectin binding pattern of both types of cells was similar, with the only exception of Arachis hypogaea agglutinin (PNA) and Triticum vulgaris agglutinin (WGA). These observations, in addition to the non statistically significant differences between morphometrical characteristics of cytotrophoblastic and cytotrophoblastic-like cells in SIPS, might suggest the fetal origin of the latter cells which could play a role in the pathogenesis of this entity.
- PublicationOpen AccessConfocal evaluation of native and induced lectin binding contributes to discriminate between lingual gland glycocomponents in quail(Murcia : F. Hernández, 2000) Bondi, A.M.; Gabrielli, M.G.; Accili, Daniela; Sabbieti, M.G.; Menghi, GiovannaA confocal analysis was performed on the quail (Coturnix coturnix japonica) lingual salivary glands where the carbohydrate chains were studied by lectin histochemistry. For this purpose, appropriate FITC- and TRITC-conjugates were used for double binding also accomplished with sialidase digestion. The glycosidic components of the quail lingual salivary glands were found to be heterogeneously distributed on the different secretory structures as well as on the single secretory elements of each adenomere. The rostra1 portion of the anterior lingual gland was found to only secrete neutral glycocomponents, characterized by terminal B-galactose, N-acetylgalactosamine and fucose residues in contrast to the caudal portion that was shown to be extremely heterogeneous and to produce sialylated glycoconjugates characterized by the terminal sequences sialic acid-B-galactose-N-acetylgalactosamine, sialic acid-13-galactose-N-acetylglucosamine,a nd sialic acida- N-acetylgalactosamine partly codistributed within secretory adenomeres. The posterior lingual gland was observed to be the major contributor to the secretion of salivary mucins containing sialoglycoconjugates with terminal sialic acid residues linked to B-galactose-Nacetylgalactosamine or a-N-acetylgalactosamine often located in distinct secretory elements.
- PublicationOpen AccessDietary mistletoe lectin supplementation and reduced growth of a murine non-Hodgkin lymphoma(Murcia : F. Hernández, 2002) Pryme, I.F.; Bardocz, S.; Pusztai, A.; Ewen, S.W.B.The growth of a murine non-Hodgkin lymphoma (NHL) tumour has been shown to be reduced by incorporating mistletoe lectin (ML-1) into the diet. The morphological characteristics of NHL tumours in mice fed ML-1-supplemented diets were different from those in LA (control)-fed mice. The degree of mitotic activity was lower and nuclear area reduced. The degree of lymphocyte infiltration was increased in tumours from ML-1 fed mice and this was accompanied by a high incidence of apoptotic bodies. Visual observation of NHL tumours from individuals fed ML-1 diet showed a poorly developed blood supply in contrast to control-fed mice. A major reduction in number of blood capillaries in NHL tumours was confirmed by microscopic evaluation of tumour sections. The results suggested an anti-angiogenic response in ML-1-fed mice. The feeding of ML-1 compared to control diet thus provided several identifiable changes in the morphology of NHL tumours which were consistent with the observed reduction in tumour weight. There was no longer histological evidence of viable tumour in 25% mice fed the ML-1 diet for 11 days. Morphological studies of the small bowel indicated (a) that the lectin induces hyperplasia, and (b) that the lectin binds avidly to lymphoid tissue of P e y e r’s patches. There was evidence of limited endocytosis of the lectin. An experiment where ML-3 was added to the diet of mice three days after inoculation of tumour cells showed that the lectin was able to slow down further growth of an established tumour. The results show that ML lectins induce powerful anti-cancer effects when provided by the oral route.
- PublicationOpen AccessExoglycosidases and lectins as sequencing approaches of salivary gland oligosaccharides(Murcia : F. Hernández, 1994) Menghi, Giovanna; Materazzi, G.This review was focused on the salivary gland oligosaccharide chains studied by lectin histochemistry combined with exoglycosidase digestion. Glycoconjugates play an important role in many biofunctions and, generally. salivary mucins, which consist of numerous oligosaccharide chains attached at closely spaced intervals to a peptide backbone, serve as lubricants and protective agents, but in many instances we are ignorant about the role of biochemically identified oligosaccharides. Lectin histochemistry represents the greatest analytic tool to study carbohydrates in situ; in addition, there is availability of selective enzymes, so glycosidase degradation is useful to both investigate the structure of a given oligosaccharide and verify the influence of neighbouring sugars on the affinity towards the respective specific lectins. Using stepwise digestion of samples, followed by lectin labelling, the structure of terminal short oligosaccharides with blood-group activity was also elucidated. Additional histochemical methodologies were developed to establish the presence of acetylated groups in sialic acid residues, and the position of the linkage to the underlying monosaccharide. Sequencing approaches by exoglycosidases and lectins were also seen to be particularly useful when substantial differences did not emerge in lectin affinity, glycoconjugate composition and complex carbohydrate cytochemistry.
- PublicationOpen AccessHistochemical analysis of carbohydrate moieties and sugar-specific acceptors in the kidneys of the laboratory mouse and the golden spiny mouse (Acomys russatus)(Murcia : F. Hernández, 1993) Coppee, I.; Gabius, H.J.; Danguy, A.The aims of this work were to histochemically compare the pattern of lectin binding and endolectin expression in different portions of nephrons of two rodent species producing either normal hyperosmotic urine (the laboratory mouse) or highly concentrated urine (Acomys russatus, the golden spiny mouse). A panel of biotinylated lectins and neoglycoproteins and the avidin-biotin-peroxidase complex technique were used on Bouin's fixed, paraffinembedded sections. Various segments of the uriniferous tubule in both species showed differential affinity for labelled lectins and neoglycoproteins. Significant differences were also evident between comparable tubular segments in laboratory and golden spiny mouse kidneys. Whether the histochemical expression of sugar moieties of glycoconjugates as well as endolectins, thus both sides of presumed protein-carbohydrate interactions, may be correlated to the various glycoproteins which would include constituents of the glycocalyx and domains of a variety of transport enzymes deserves further studies.
- PublicationOpen AccessImmunohistochemical and lectin histochemical analysis of the alpaca efferent ducts(Murcia : F. Hernández, 2009) Parillo, F.; Magi, G.E.; Diverio, S.; Catone, G.An immunohistochemical and lectin histochemical study of the efferent ducts was performed in the alpaca. Two types of epithelium, consisting of principal and ciliated cells, were detected on the basis of the different cytokeratins expression and lectin binding pattern. AE1/AE3 and 13 cytokeratin antibodies intensely immunostained the entire cytoplasm of type I PCs, whereas AE1/AE3, but not anti cytokeratin 13, immunoreacted in type II principal cells along the apical, lateral and basal plasma-membrane. The histochemical characterization of the epithelial cells was carried out using a battery of different lectins: Con-A, UEA-I, LTA, WGA, GSA-II, GSA-IB4, SBA, PNA, ECA, DBA, MAL-II and SNA. Sialidase digestion and deglycosilation pre-treatments were also employed. In type I principal cells, the staining of the Golgi zone was interpreted giving evidence for the synthesis and secretion of O- and N-linked oligosaccharides. In particular, a-Man/a-Glc, GlcNAc, ß-Gal-(1-4)-GlcNAc, Neu5Aca2,3Gal and Neu5Aca2,6Gal/GalNAc residues were included in both O- and N-linked glycans, whereas a-Fuc, ß-GalNAc and a-Gal were only found in Olinked oligosaccharides; a-GalNac and ß-Gal-(1-3)-DGalNAc were found subterminal to sialic acid moieties and they were included in O- and N-glycans. In type II principal cells, the lectin staining was observed in the apical cytoplasmic granules and in vacuoles that were interpreted as components of an elaborate endocytotic apparatus specialized for the uptake of particulate material and fluid from the lumen. These results suggest the existence of two structurally different epithelial segments along the ductuli efferentes of the alpaca, with a high degree of compartmentalization of the secretory and absorptive activities.
- PublicationOpen AccessImmunohistochemical profile of galectin-8 expression in benign and malignant tumors of epithelial, mesenchymatous and adipous origins, and of the nervous system(Murcia : F. Hernández, 2001) Danguy, A.; Rorive, S.; Decaestecker, C.; Bronckart, Y.; Kaltner, H.; Hadari, Y.R.; Goren, R.; Zich, Y.; Petein, M.; Salmon, I.; Gabius, H.J.; Kiss, R.This study aims to investigate whether the immunohistochemical expression of galectin-8 could be used as a diagnostic marker in tumor tissues of various histogenetic origins including specimens from epithelial (n=145), mesenchymatous (n=16), adipous (n=10) and central and peripheral nervous system (n=25) tissue, and 4 mesotheliomas. Immunohistochemical reactions were carried out with a polyclonal anti-galectin-8 antibody and histological slides from tissues derived from the files of the Laboratory of Anatomopathology of University Erasmus Hospital, Brussels. Formalin-fixed paraffinembedded tissues of 45 normal cases as well as 41 benign and 114 malignant tumors were studied. Marked decreases in immunohistochemical galectin-8 expression were obsewed in colon (p=0.001), pancreas (p=0.007), liver (p=0.0008), skin (p=0.002) and larynx (p=0.02) tissue when comparing malignant tissue to normal tissue andlor benign tumors. The reverse relationship was observed for breast tissue (p=0.007). No statistically significant differences (p>0.05) were detected when comparing normal tissue andlor benign to malignant tumors in lung, bladder, kidney, prostate and stomach tissue. Significant galectin-8 expression was also measured in non-epithelial tissue including tumors of the central and peripheral nervous system as well as in skeletal muscle and mesotheliomas. Immunohistochemical monitoring of galectin-8 thus reveals an organtype- dependent regulation of expression upon malignant transformation of various tissue types of epithelial origin. This observation will prompt further studies to 0ffprin.int requests to: Roberl Kiss, Ph.D., Laboratory of Histopathology, Faculty of Medicine - Free University of Brussels, 808 route de Lennik - 1070 Brussels, Belgiurn. Fax: 322 555 62 85. e-rnail: rkiss@ulb.ac.be delineate any relationship with prognosis
- PublicationOpen AccessLectin binding in the human endometrium in early luteal phase following controlled ovarian hyperstimulation(Murcia : F. Hernández, 1998) Gheri, G.; Gheri Bryk, S.; Taddei, G.; Borri, P.; Noci, I.A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties on the endometrial epithelium and stroma in 12 women undergoing controlled ovarian hyperstimulation (COH) for in-vitro fertilisation for embryo transfer (IVF-ET) in early luteal phase. 7 control subjects were also evaluated. For this purpose a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEA I) was used. Cytochemical controls were performed for specificity of lectin-sugar reaction. As far as the endometrial glands and stroma are concerned, the obtained data showed no differences in the endometrial lectin binding between the subjects of the control group and the ones undergoing COH, with the exception of PNA reactivity at the level of the apical portion of the glandular cells, which was detected only in COH women. It is noteworthy that, although the endometrial dating using the Noyes's criteria showed marked dissynchronies between the stroma and the glands in COH subjects, a uniformity of lectin binding, revealing the same type and localization of terminal oligosaccharides, was observed in all the examined subjects. The uniformity in distribution of the sugar residues detected in the endometrial specimens following COH might be due to the massive FSH and/or hCG treatment which probably determines an endometrial environment almost equal in all the examined subjects. In all the treated subjects reactivity with sialidase-WGA and ConA, revealing the presence of Nacetyl -D-glucosamine and D-mannose respectively, was detected at the level of the lining epithelium.
- PublicationOpen AccessLectin cytochemistry on developing rat submandibular gland primary cultures(Murcia : F. Hernández, 2004) Sabbieti, M.G.; Gabrielli, M.G.; Menghi, Giovanna; Materazzi, G.; Marchetti, L.Lectin cytochemistry was performed in vitro on primary cultures from the rat submandibular gland. For this purpose, prepubertal rats (17, 27, 33 days old) of both sexes were used. Several types of medium supplements were tested and it was found that cells survived until 15 days in presence of all medium supplements and extracellular matrix gel. The binding patterns of all FITC/TRITC-labeled lectins, with and without prior sialidase digestion and deacetylation, were analyzed in a confocal laser scanning microscope. In particular, the occurrence of C4 acetylated sialic acid linked to ß-galactose at day 27 and the presence of fucose residues at day 33 indicated that lectin probes applied to cultured cells give results similar to those obtained in intact tissues and can be used as markers of growth and differentiation.
- PublicationOpen AccessLectins as differentiation markers of human gliomas(Murcia : F. Hernández, 1991) Figols, J.; Cervós-Navarro, J.; Madrid Cuevas, Juan FranciscoThe lectins Concanavalin A (Con A). Ricinus communis agglutinin (RCA-1), Peanut agglutinin (PNA) and Wheat germ agglutinin (WGA) as well as the irnmunomarkers for glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) were used in a series of 21 glial turnors (4 pylocytic astrocytornas, 5 grade 11 astrocytornas, 3 anaplastic astrocytornas, 4 glioblastornas and 5 oligodendrogliornas). ConA binds to al1 tumoral astrocytes in low grade astrocytomas, as well as to well differentiated tumoral astrocytes in anaplastic astrocytomas and glioblastornas. RCA-1 has a similar behaviour. PNA, and to a lesser degree WGA, binds selectively to the oligodendroglial plasma membrane in well differentiated oligodendrogliomas. The results suggest that these lectins are markers of differentiation in gliomas rather than of malignancy.
- PublicationOpen AccessSialic acid expression in human fetal skeletal muscle during limb early myogenesis(Universidad de Murcia. Departamento de Biología Celular e Histología, 2017) Marini, Mirca; Sarchielli, Erica; Zappoli Thyrion, Giorgia Donata; Ambrosini, Stefano; Sgambati, EleonoraInvestigations on animal models demonstrated that changes of sialic acid (SA) expression, particularly the polymeric form, in the skeletal muscle during embryonic and post-natal development seem to be related to muscle differentiation and functionality onset. The aim of this study was to evaluate the monomeric and polymeric SA expression in human skeletal muscle during early stages of fetal development, when important morphofunctional events occur. Specimens of fetal skeletal muscle from limb, between 9 and 12 weeks of gestation (wg), were obtained from 19 pregnant women. To investigate some morphofunctional features occurring during this development period, haematoxylin-eosin staining, tunel assay and immunohistochemistry for connexin-43 (Cx43) and parvalbumin were performed. SA expression and characterization was evaluated using lectin histochemistry (MAA, SNA, PNA, SBA, DBA), associated with enzymatic and chemical treatments. Polysialic acid (PSA) expression was also evaluated using immunohistochemistry. The results showed apoptotic myotubes between 9 and 10.5 wg, disappearing from 11 wg; Cx43 was more abundant in myotubes/myoblasts between 9 and 9.5 wg, decreasing and/or disappearing from 10 wg and parvalbumin was present in myotubes between 10 and 10.5 wg. PSA was revealed in myotubes/myoblasts from 9 to 10.5 wg; from 11 wg it was reduced or disappeared. Monomeric SA appeared in myotubes/myoblasts from 10 wg, increasing successively; acetylated SA was present from 11 wg. These findings demonstrated that changes in expression of various types of SA, occurring in human fetal skeletal muscle during early development, seem to be related to some morphofunctional aspects distinctive of this organogenesis crucial period.
- PublicationOpen AccessSugar residues content and distribution in atrophic and hyperplastic postmenopausal human endometrium: lectin histochemistry(Murcia : F. Hernández, 1996) Gheri, G.; Gheri Bryk, S.; Taddei, G.; Moncini, D.; Noci, I.A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties of the human postmenopausal endometrium (14 atrophic and 15 hyperplastic). For this purpose a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEA I) was used. No differences in lectin binding between atrophic and hyperplastic endometria were observed. This investigation allowed us to provide a basic picture of the oligosaccharidic distribution in postmenopausal endometria. The data on the saccharidic distribution at the postmenopausal endometria showed a large amount of sugar residues at all the investigated sites, i.e. the lining and glandular epithelium, the stroma and the vessels (capillary and large vessels). Furthermore, at the endometrial lining epithelium, at the glands and at the wall of the blood vessels of some postmenopausal women the presence of a-L-fucosyl residues which bind via a (1-6) linkage to penultimate glucosaminyl residues andtor difucosylated oligosaccharides was demonstrated for the first time.