Publications

TitleAbstractYear
Filter
PMID(sorted ascending)
Filter
a solid-phase assay for the activity of cmpneuac:gal beta 1-4glcnac-r alpha-2,6-sialyltransferase.a solid-phase assay for the activity of cmpneuac:gal beta 1-4glcnac-r alpha-2,6-sialyltransferase (2,6st) has been developed. in the assay an acceptor glycoprotein is immobilized onto microtiter plate wells. the two glycoprotein acceptors used were asialofetuin (asf), which contains oligosaccharides terminating in the sequence gal beta 1-4glcnac-r, and a neoglycoprotein of bovine serum albumin containing covalently attached gal beta 1-4glcnac-r units. samples containing the donor cmpneuac and th ...19921280007
p-selectin and e-selectin. distinct but overlapping leukocyte ligand specificities.p-selectin on platelets and endothelial cells and e-selectin on endothelial cells are leukocyte receptors that recognize lineage-specific carbohydrates on neutrophils and monocytes. the proposed ligands for these receptors contain the le(x) core and sialic acid. since other investigators have shown that both e-selectin and p-selectin bind to sialylated le(x), we evaluated whether e-selectin and p-selectin recognize the same counter-receptor on leukocytes. the interaction of hl60 cells with chine ...19921375936
the use of streptavidin-biotinylglycans as a tool for characterization of oligosaccharide-binding specificity of lectin.a new rapid and sensitive method for characterizing lectin specificity using streptavidin-biotinylglycans as a tool is presented. this assay is analogous to enzyme immunoassay and takes advantage of the strong, irreversible adsorption of streptavidin to the wells of the chambers of titer plates. a series of streptavidin-biotinylglycans was first coated on a microtiter plate, and then one of six lectins, concanavalin a, wheat germ agglutinin, phaseolus vulgaris (red kidney bean) erythro-agglutini ...19921443561
n-glycosylation site mapping of human serotransferrin by serial lectin affinity chromatography, fast atom bombardment-mass spectrometry, and 1h nuclear magnetic resonance spectroscopy.this report describes the n-glycosylation site mapping of human serotransferrin (h-stf). reduced and s-carboxymethylated h-stf was digested with trypsin or chymotrypsin. glycopeptides in the proteolytic digests were isolated by serial concanavalin a (con a), sambucus nigra agglutinin (sna), and phaseolus vulgaris leukoagglutinin (lpha) affinity chromatography and subjected to preliminary analysis by 1h nmr spectroscopy. the glycopeptide fractions were then individually digested with n-glycanase. ...19921456441
characterization of carbohydrate chains of c1-inhibitor and of desialylated c1-inhibitor.carbohydrate chains of c1-inhibitor were identified with a binding assay using different lectins. lectins from sambucus nigra (sna) and maackia amurensis (maa) that are specific for sialic acids bound to c1-inhibitor. lectin from datura stramonium (dsa) reacted also with the inhibitor indicating complex and hybrid sugar structures. c1-inhibitor was enzymatically desialylated and reexamined for lectin binding. sna and maa did not react anymore, but in addition to dsa, peanut agglutinin, which can ...19921468580
a sub-population of keratan sulphates derived from bovine articular cartilage is capped with alpha(2-6)-linked n-acetylneuraminic acid residues. affinity chromatography using immobilized sambucus nigra lectin and characterization using 1h n.m.r. spectroscopy.alkaline borohydride-reduced keratan sulphate (ks) chains derived from bovine femoral head cartilage were fractionated by lectin affinity chromatography with sambucus nigra agglutinin (sna) into binding and non-binding populations. analysis of the sna-binding and non-binding ks chains using 600 mhz 1h n.m.r. spectroscopy showed that the former population contained alpha(2-6)-n-acetylneuraminic acid residues and the latter contained primarily alpha(2-3)-n-acetylneuraminic acid residues as chain t ...19921520274
the c-ha-ras oncogene induces increased expression of beta-galactoside alpha-2, 6-sialyltransferase in rat fibroblast (fr3t3) cells.alteration in cell surface carbohydrates, and in particular cell surface sialylation, have been known to occur during oncogenic transformation. to examine the basis for such changes, we have transformed the rat fibroblast cell line fr3t3 with the oncogenes c-ha-ras ej, v-mycok10, v-src, polyoma virus middle t or the transforming bovine papilloma virus 1 (bpv1), and measured the sialytransferase activities of cellular lysates. we found that, in contrast to all other oncogenes examined, c-ha-ras i ...19921550989
structure of the n-linked oligosaccharides of the human transferrin receptor.human transferrin receptor was isolated from placenta and from the hepatocarcinoma cell line hep g2. asparagine-linked oligosaccharides were released by treatment of tryptic glycopeptides with endo-beta-n-acetylglucosaminidase h or peptide-n4-(n-acetyl-beta-glucosaminyl)asparagine amidase f. oligosaccharide alditols were fractionated by anion-exchange high-performance liquid chromatography and by high-ph anion-exchange chromatography. glycans from placental transferrin receptor were further char ...19921555586
the major kurloff cell glycoproteins: lectin affinities, glycosidase susceptibilities and relationship with the sialylated acid phosphatases of the kurloff body.urea-soluble fractions from purified kurloff cells (kc) were analysed by affinoblotting. lectin reactivities were quasi-exclusively confined to the 30-35 kda major glycoproteins (mgps) (responsible for the pas positivity of the kurloff body) with strong affinities for canavalia ensiformis lectin, phaseolus vulgaris erythroagglutinin and sambucus nigra (sna), pisum sativum, triticum vulgaris and ulex europeus agglutinins. these data were consistent with the presence, among the kc mgps, of large a ...19921581339
alpha-d-galactose-bearing glycoproteins on the surface of stimulated murine peritoneal macrophages. biochemical and immunochemical characterization of purified glycoproteins.two glycoproteins were isolated from lysates of thioglycollate-stimulated, murine peritoneal macrophages by affinity chromatography on immobilized griffonia simplicifolia i lectin and by preparative sds/page. the glycoproteins were readily labeled on the surface of intact macrophages with 3h and 125i. the labeled glycoproteins migrated as broad bands of molecular mass 92-109 kda and 115-125 kda. the mobility of the glycoproteins decreased only slightly after reduction with dithiothreitol, indica ...19921587269
separation of flavonol-2-o-glycosides from calendula officinalis and sambucus nigra by high-performance liquid and micellar electrokinetic capillary chromatography.calendula officinalis and sambucus nigra flowers were analysed by reversed-phase high-performance liquid chromatography (rp-hplc) and micellar electrokinetic capillary chromatography (mecc). rp-hplc was performed on c8 aquapore rp 300 columns with eluents containing 2-propanol and tetrahydrofuran. mecc was carried out on a 72-cm fused-silica capillary using sodium dodecyl sulphate and sodium borate (ph 8.3) as the running buffer. the results obtained by these techniques are compared.19921639901
expression of alpha 2,6-linked sialic acid residues in neoplastic but not in normal human colonic mucosa. a lectin-gold cytochemical study with sambucus nigra and maackia amurensis lectins.increased sialylation of cell surface glycoconjugates has been demonstrated in malignant tumors and shown to be correlated with the invasive and metastatic growth of colon carcinoma cells. the authors have applied the maackia amurensis lectin, which interacts with alpha 2,3-linked sialic acid, and the sambucus nigra i lectin specific for alpha 2,6-linked sialic acid. in human colon, alpha 2,3-linked sialic acid was detectable in normal and transitional mucosa as well as in adenomas with differen ...19911661075
structural analysis and functional role of the carbohydrate component of somatostatin receptors.srif receptors are membrane-bound glycoproteins. to structurally identify the carbohydrate components of srif receptors, solubilized rat brain srif receptors were subjected to lectin affinity chromatography. solubilized srif receptors specifically bound to wheat germ agglutinin-lectin affinity columns but not to succinylated wheat germ agglutinin. this finding, as well as the ability of the solubilized receptor to interact with a sambucus nigra l. lectin affinity column suggested that sialic aci ...19911682310
lectin binding patterns to terminal sugars of rat lung alveolar epithelial cells.we used post-embedding cytochemical techniques to investigate the lectin binding profiles of rat lung alveolar epithelial cells. sections from rat lung embedded in the hydrophilic resin lowicryl k4m were incubated either directly with a lectin-gold complex or with an unlabeled lectin followed by a specific glycoprotein-gold complex. the binding patterns of the five lectins used could be divided into three categories according to their reactivity with alveolar epithelial cells: (a) the limax flav ...19901688898
[properties of the cell surface of normal and malignant cells: investigations on polysialic acid and terminal sialic acid residues in specific linkages].data are reported to demonstrate the usefulness of a monoclonal anti-polysialic acid antibody for (i) the visualization of immature and mature neural elements in human teratomas, and (ii) the distinction of small cell lung carcinoma from bronchial carcinoids as well as squamous cell and adenocarcinomas of the lung. lectins which discriminate between the various types of sialylated sequences, such as the sambucus nigra l. i lectin specific for neu5ac alpha 2,6 gal/galnac and the leukoagglutinin f ...19901708580
[a method of selective histochemical analysis of sialoglycoproteins using lectins from elder (sambucus nigra l.)].good potentialities in application of elderberry (sambucus nigra l.) bark lectin for selective histochemical identification of sialylated glycoconjugates has been demonstrated using lectin-peroxidase technique. in order to omit this lectin binding to d-galactose and n-acetyl-d-galactosamine residues, preincubation of tissue sections with non-marked pna and sba (or other lectins with similar carbohydrate specificity) is proposed. by means of neuraminidase digestion it has been ascertained, that o ...19911711385
enhanced cmp-neuac:gal beta 1,4glcnac-r alpha 2,6 sialyltransferase activity of human colon cancer xenografts in athymic nude mice and of xenograft-derived cell lines.the activity of an alpha 2,6 sialyltransferase acting on n-acetyllactosaminic sequences (alpha 2,6 st e.c. 2.4.99.1) has previously been found to be increased in 90% of human colon cancer specimens. in the present study, the alpha 2,6 st activity of 6 human colon cancer cell lines grown in culture was compared with that expressed by the corresponding nude mice xenografts and by the cell lines derived from the xenografts. we found that xenografts of colo 205, ht-29, sw 620, sw 948 and sw 948 fl ( ...19921730528
alpha 2,6 sialylation of n-acetyllactosaminic sequences in human colorectal cancer cell lines. relationship with non-adherent growth.in a previous work we found that human colorectal cancer tissues express increased levels of an alpha 2,6 sialyltransferase (alpha 2,6 st) acting on n-acetyllactosaminic sequences (e.c. 2.4.99.1). in this study we have taken advantage of the known specificity of elderberry bark lectin (sambucus nigra agglutinin, sna) for neuac alpha 2, 6gal/galnac structures to investigate the relationship between expression of alpha 2,6 sialyltransferase activity and occurrence of alpha 2,6-sialylated oligosacc ...19911899084
purification and partial characterization of a novel lectin from elder (sambucus nigra l.) fruit.a previously unknown haemagglutinin, named sambucus nigra agglutinin-iii (sna-iii), has been purified from the fruit of the elder (sambucus nigra). whereas elder bark agglutinin i (sna-i) is highly specific for terminal alpha 2,6-linked sialic acid residues, sna-iii displays a high affinity for oligosaccharides containing exposed n-acetylgalactosamine and galactose residues. different n-terminal sequences and the amino acid composition distinguish the fruit lectin from elder bark agglutinin ii ( ...19911910334
selective loss of sialic acid from rat small intestinal epithelial cells during postnatal development: demonstration with lectin-gold techniques.post-embedding lectin-gold cytochemistry was employed to investigate the distribution of sialic acid and fucose residues in rat small intestinal epithelial cells during postnatal development. during the suckling phase (postnatal day 1) the apical and basolateral plasma membranes of epithelial cells, as well as the goblet cell mucus was intensely stained with the sialic acid-specific sambucus nigra l. lectin i-gold complex (snl i-g). by the weaning period (postnatal day 23), the entire villus con ...19902081543
sialyloligosaccharides of the respiratory epithelium in the selection of human influenza virus receptor specificity.human h3 strains of influenza a virus preferentially bind cell-surface oligosaccharides containing the sequence neuac alpha 2,6gal, while avian influenza strains preferentially recognize the sequence neuac alpha 2,3gal. the distribution of these two types of sialic acid linkages on host respiratory epithelium, the target of influenza infection, may be a factor in the selection of the different receptor specificities observed in human and avian influenza strains. to examine the distribution of th ...19902091044
characterization of galactose-containing glycoconjugates in the human retina: a lectin histochemical study.seven specimens of morphologically normal formalin-fixed and paraffin-embedded human retina were studied using a panel of fourteen biotinylated lectins, all of which react with glycoconjugates containing galactose and n-acetylgalactosamine residues. agaricus bisporus (aba), bauhinia purpurea (bpa), phaseolus vulgaris (pha-e), peanut (pna) and ricinus communis (rca-i) agglutinins labeled photoreceptor cells prior to enzymatic predigestion. bpa and pna bound specifically to cones. the plexiform la ...19902091899
comparison of the lectin-like activity of pertussis toxin with two plant lectins that have differential specificities for alpha (2-6) and alpha (2-3)-linked sialic acid.in this report we have compared the lectin-like properties of pertussis toxin with two plant lectins which are known to possess different specificities towards terminal neu5ac gal linkages on glycoconjugates. the hemagglutinin from elderberry bark (sambucus nigra) has a binding specificity for terminal neu5ac alpha (2-6) gal sequences and was found to bind a series of glycoconjugates with a similar specificity as pertussis toxin. the binding specificity of pertussis toxin was different from that ...19902244906
relationship between survival and binding of plant lectins during small intestinal passage and their effectiveness as growth factors.the effects on the small intestine and the growth of rats of six pure plant lectins: pha (phaseolus vulgaris); sbl (glycine maxima); sna-i and sna-ii (sambucus nigra); gna (galanthus nivalis) and vfl (vicia faba), covering most sugar specificities found in nature, were studied in vivo. variable amounts, 25% (vfl) to 100% (pha, gna) of the lectins administered intragastrically, remained in immunochemically intact form in the small intestine after 1 h. all lectins, except gna, showed binding to th ...19902262064
lectin-binding properties of burkitt's lymphoma cell lines: application to bone marrow purging.the efficacy of binding of several lectins to different burkitt's lymphoma (bl) cell lines was investigated. soybean agglutinin (sba), peanut agglutinin (pna), wheat germ agglutinin (wga), and sambucus nigra agglutinin (sna) bound strongly to all bl cell lines. because sba has been used safely in clinical bone marrow transplantation (bmt) as part of the procedure for t-cell depletion and hence does not bind to the stem cells, we chose this lectin to establish a model for purging bl cells from hu ...19902298270
elderberry bark lectin--gold techniques for the detection of neu5ac (alpha 2,6) gal/galnac sequences: applications and limitations.the lectin from the elderberry (sambucus nigra l.) bark, shown to recognize the sequence neuraminic acid (alpha 2,6) galactose/n-acetylgalactosamine, was applied for detecting binding sites in lowicryl k4m sections by light and electron microscopy. the lectin was used either directly complexed to colloidal gold or in a two-step cytochemical affinity technique. the lectin-gold complex proved to be superior and thus was extensively tested on rat liver, kidney and hepatoma cells as well as on sheep ...19882467894
distinction of influenza viruses of different host cell origin.influenza a viruses grown in different animal or human cells retain their antigenic make-up as tested by the usual immunological assays. with the aid of a sambucus nigra (l.) extract containing its lectins the viruses can be distinguished after one single passage in a different cell type by a change in their hemagglutinating properties. binding of such lectins to influenza viruses may be a means for a more subtle classification, relating to the host cell origin of the virus.19892737269
glycaemic effects of traditional european plant treatments for diabetes. studies in normal and streptozotocin diabetic mice.twelve plants used for the traditional treatment of diabetes mellitus in northern europe were studied using normal and streptozotocin diabetic mice to evaluate effects on glucose homeostasis. the plants were administered in the diet (6.25% by weight) and/or as decoctions or infusions in place of drinking water, to coincide with the traditional method of preparation. treatment for 28 days with preparations of burdock (arctium lappa), cashew (anacardium occidentale), dandelion (taraxacum officinal ...19892743711
enrichment for gm-cfu from human bone marrow using sambucus nigra agglutinin: potential application to bone marrow transplantation.a new lectin, purified from black elder-berries, sambucus nigra l. (sna i, hereafter called sna), was used for fractionation of normal human marrow cells. the stem cell enrichment capability of sna was investigated by comparing colony formation (gm-cfu) in unagglutinated cell fractions (sna-) following agglutination with sna with that with soybean agglutinin (sba-). gm-cfu recovery in sna- was equal or superior to that in the sba- fraction. a modified procedure was developed to combine stem cell ...19863533587
the amino acid sequences of cytochrome c from four plant sources.proposed amino acid sequences of cytochrome c from nasturtium (tropaeolum majus l.), box-elder (acer negundo l.), elder (sambucus nigra l.) and parsnip (pastinaca sativa l.) are presented. because of the very limited amounts of cytochrome available from some plant sources, peptides derived from the cytochromes c have been sequenced by the semi-quantitative dansyl-edman technique (gray & hartley, 1963) without supporting quantitative amino acid analyses. because of the qualitative nature of the w ...19744362498
the 70-kilodalton pertussis toxin-binding protein in jurkat cells.125i-asd photoaffinity-labeling derivatives of pertussis toxin (125i-asd-pt) or lipopolysaccharide (125i-asd-lps) labeled similar 70-kda proteins in jurkat cells, a cell line derived from human cd4+ t lymphocytes. labeling of this 70-kda protein by 125i-asd-pt was inhibited by underivatized pt but not by underivatized lps. however, an immunoglobulin m monoclonal antibody with specificity for the p73 lps receptor in murine splenocytes (s. w. bright, t.-y. chen, l. m. flebbe, m.-g. lei, and d. c. ...19947514575
[h2o2 generation and human neutrophil aggregation as affected by lectins].the effects of eight plant lectins on human neutrophils aggregation and h2o2 release were studied. both processes were stimulated by lectins from viscum album, triticum vulgaris, phaseolus vulgaris and canavalia ensiformis while lectins from solanum tuberosum, sambucus nigra and glycine mas displayed only aggregating activity and arachis hypogaea lectin was not effective. heating (46 degrees c) and uv-radiation during 4-5 min were found to suppress completely h2o2 release from neutrophils keepin ...19957557235
alpha-2,3 sialylation differentiate the limbal and corneal epithelial cell phenotypes.the initial differentiation event for the corneal epithelial cell lineage occurs as the limbally localized stem cells yield, through mitosis, the highly proliferative, transiently amplifying corneal peripheral cells. this differentiation is characterized by the expression of tissue-specific cytokeratins, as well as the loss of alpha-enolase and pigmentation. all these are intracellular events. the aim of this study was to identify and characterize, through lectin analysis, changes in cell surfac ...19957558722
agglutination of streptococcus suis by sialic acid-binding lectins.the 35 streptococcus suis capsular-type reference strains as well as 45 field strains of type 2 were tested with sialic acid-binding lectins from sambucus nigra (sna i), triticum vulgaris, maackia amurensis, homarus americanus, and limax flavus. only types 1, 1/2, 2, 14, 15, and 16 agglutinated with sna i and/or the t. vulgaris lectin. all field strains agglutinated only with sna i. reaction with sna i was probably due to the sialic acid moiety since it disappeared after sialidase treatment. the ...19957559986
prostaglandin e2 alters terminal glycosylation of high molecular weight glycoproteins, released by pig gastric mucous cells in vitro.the gastric mucus layer consists of high molecular weight glycoproteins (hmg). e-type prostaglandins (pgs) stimulate total hmg release from isolated gastric mucous cells. we determined the effects of pge2 on hmg glycosylation. pig gastric mucous cells were cultured for 20 h with 1 mumol/l pge2. released hmg were isolated by gel chromatography and periodic acid-schiff (pas)-positive sugars and protein-bound [14c]glcnac were determined. monosaccharides terminally linked to hmg oligosaccharide chai ...19957630922
expression of gal beta 1,4glcnac alpha 2,6-sialyltransferase and alpha 2,6-linked sialoglycoconjugates in normal human and rat tissues.we performed histochemical studies on normal human and rat tissues using anti-gal beta 1,4glcnac alpha 2,6-sialyltransferase (alpha 2,6-st) antibody and sambucus nigra agglutinin (sna). alpha 2,6-st and its products were detected in almost all tissues examined. however, the staining intensities varied significantly with different cell types. some secretory epithelial cells, such as hepatocytes and choroid plexus cells, were vividly stained with either anti-alpha 2,6-st or sna. in several cell ty ...19957642967
transcriptional induction of beta-galactoside alpha-2,6-sialyltransferase in rat fibroblast by dexamethasone.the beta-galactoside alpha-2,6-sialyltransferase activity of fisher rat fibroblasts is enhanced by dexamethasone while the activity of the beta-galactoside alpha-2,3-sialyltransferase remains unchanged. this glucocorticoid-dependent activation can be inhibited by the antagonist ru 38,486 and results from an elevated transcription rate of the 4.7-kb mrna previously characterized in rat fibroblasts, distinct from the 4.3-kb liver-restricted mrna. as shown by the binding of radiolabelled sambucus n ...19937678804
toxoplasma gondii: uptake of fetuin and identification of a 15-kda fetuin-binding protein.lectin-binding studies demonstrated the presence of a 68-kda glycoprotein in tachyzoites of toxoplasma gondii harvested from p388d1 macrophage cell cultures but not in tachyzoites maintained in peritoneal cavities of nmri mice. this protein was identified as the embryonic protein fetuin that regularly is contained in fetal calf serum, a component of cell-culture media. uptake of fetuin by t. gondii was demonstrated by intracellular localization of this protein. as shown by latex agglutination an ...19937684138
determination of the sialic acid linkage specificity of sialidases using lectins in a solid phase assay.a procedure for the determination of activity and linkage specificity of sialidases is described. the sialoglycoprotein fetuin is coated onto a microtiter plate and incubated with sialidases from different sources. enzymatic activities and linkage specificities are then determined by a sandwich method which measured the binding of different lectins to fetuin. the lectins used were peanut agglutinin (pna) from arachis hypogaea, which binds specifically the galactose beta-1-3-n-acetylgalactosamine ...19937686353
expression of alpha 2,6-sialylated sugar chains in normal and neoplastic colon tissues. detection by digoxigenin-conjugated sambucus nigra agglutinin.it has previously been reported that about 90% of human colon carcinomas express increased levels of the sialyltransferase which adds sialic acid in alpha 2,6 linkage to galactose residues on n-linked chains of glycoproteins. to ascertain whether colon cancer tissues actually express increased amounts of alpha 2,6-sialylated sugar chains on their glycoconjugates, we screened tissue sections of normal colon, benign and malignant colon tumors with digoxigenin-conjugated sambucus nigra agglutinin ( ...19937693064
neuraminic acid specific lectins as markers of early cortical plate neurons.early cortical plate and subplate cells in the developing neocortex of many animal species and humans contain one specific plasma protein, fetuin. fetuin is heavily glycosylated and it is possible that due to the large amount of sugars, this molecule may play a part in cellular recognition during brain development. cellular and extracellular carbohydrates in the developing brain of the sheep were studied histochemically using a battery of fluorescein-labelled lectins. two neuraminic acid specifi ...19937694444
maackia amurensis agglutinin discriminates between normal and chronic leukemic human lymphocytes.altered glycosylations of cell surface glycoproteins often accompany malignant transformation and lectins are useful for probing these alterations. lymphocytes exhibit characteristic surface glycoproteins which serve as markers of cell status and development. the present work was undertaken to compare, on blots, the binding characteristics of membranes isolated from normal peripheral blood lymphocytes and chronic lymphatic leukemia cells to five different lectins, from datura stramonium, maackia ...19957733985
changes in glycan distribution within the porcine interhaemal barrier during gestation.changing patterns of glycan distribution are described in porcine placentae at 15, 19, 26, 43, 58, 69 and 109 days gestation, using a carefully selected panel of lectins that allowed partial analysis of saccharide classes and sequences. the lectins used were from galanthus nivalis, pisum sativum, phaseolus vulgaris (leukohaemagglutinin), triticum vulgaris, tetragonolobus purpureus, ulex europaeus-1, arachis hypogaea, erythrina cristagalli, glycine max, maclura pomifera, wisteria floribunda, doli ...19957736552
estrous cycle-related alterations in the expression of glycoconjugates and lectins in the mouse endometrium shown histochemically.alterations of the hormonal status may influence diverse cell features relevant to intra- and intercellular communication. we studied histochemically the expression of glycans and endogenous sugar-binding proteins (endolectins) in the mouse endometrium during the estrous cycle. the avidin-biotin-peroxidase complex (abc) technique was used on paraffin sections with a panel of biotinylated lectins and neoglycoproteins. stage-specific changes were observed with galanthus nivalis agglutinin (gna), u ...19957778095
high alpha-2,6-sialylation of n-acetyllactosamine sequences in ras-transformed rat fibroblasts correlates with high invasive potential.through cloning experiments with the frras ej4 cell line, previously described to exhibit a sambucus nigra agglutinin (sna)+ phenotype, three clones with a sna- phenotype were isolated. all the selected sna+ and sna- clones expressed the ras oncoprotein and cloned in soft agar with the same efficiency. we were interested in studying the adhesion and invasion properties of the frras cells presenting a sna + or - phenotype. they were first compared in their biochemical properties and we found that ...19957780196
human colon cancer cell lines permanently expressing alpha 2,6-sialylated sugar chains by transfection with rat beta-galactoside alpha 2,6 sialyltransferase cdna.a role of alpha 2,6-linked sialic acid in the development of an invasive phenotype in colon cancer has been suggested by several observations but never conclusively demonstrated. an experimental model to clarify this tissue was established by the creation and characterization of a bank of cell lines that differ mainly, if not exclusively, in the degree of alpha 2,6-sialylation. human colon cancer cell lines sw48 and sw948, normally unable to elaborate the alpha 2,6-sialyl linkage, were transfect ...19957794269
wild-type and cultured ehrlich ascites tumour cells differ in tumorigenicity, lectin binding patterns and binding to basement membranes.three different variants of the ehrlich ascites tumour (eat) cell were derived and the lectin surface reactivities, as well as the malignant characteristics of each variant, were studied. wild-type cells (eat-wt) were selected for growth on basement membranes and tissue culture plastic to give eat-c cells. the eat-c were passaged in mice by i.p. injection, giving rise to a third variant (eat-c/m). each of these three cell variants was characterized for: (i) specific lectin agglutinability patter ...19947827403
lectin-histochemical analysis of glycans in ovine and bovine near-term placental binucleate cells.chorionic binucleate cells (bnc) occur in several ruminants including cow, deer, goat and sheep. they migrate through the chorionic tight junction to fuse with uterine epithelial cells and discharge their granules into maternal connective tissue. we have compared the bnc of near-term, resin-embedded, ovine and bovine placentae using 15 biotinylated lectins and an avidinperoxidase revealing system. there was pronounced conservation of saccharides between the two species. several sub-types of n-gl ...19947850870
characterization of human arylsulfatase a glycans.despite numerous studies on arylsulfatase a, the structure of the glycans present in each of its two subunits has not been determined. this is important because the carbohydrate component of human arylsulfatase a synthesized in tumor tissues and transformed cells has been shown to undergo apparent changes. this study elucidates some of their major features. glycan chain analysis of native and deglycosylated arylsulfatase a as well as its subunits was performed with the use of a glycan differenti ...19947890120
bovine retinal rod guanyl cyclase represents a new n-glycosylated subtype of membrane-bound guanyl cyclases.the molecular properties of retinal rod guanyl cyclase were investigated. peptides were derived from a 112-kda protein previously identified as the particulate bovine retinal rod guanyl cyclase. the peptides showed 100% identity to the deduced amino acid sequence of the cloned human retina-specific membrane guanyl cyclase, whereas identity to the members of the natriuretic peptide receptor guanyl cyclases was 14-59%. the 112-kda protein was further purified by a new approach using wheat-germ agg ...19947912673
in situ characterization of the human hyalocyte.to provide more definitive evidence regarding the cellular origin of hyalocytes and to establish a basis for their identification in tissue specimens.19947945040
human zona pellucida recognition associated with removal of sialic acid from human sperm surface.the ability of human spermatozoa recovered from highly motile sperm fractions to bind wheat germ agglutinin (wga) after discontinuous percoll gradient centrifugation was studied. wga could bind to almost all motile spermatozoa, whereas fewer than 25% of spermatozoa could bind peanut (pna) and concanavalin a (con a) agglutinin, two lectins that specifically bind acrosomal membranes. after removal of the plasma membrane with 0.04% triton x100, wga, pna and con a bound more than 80% of spermatozoa, ...19947966029
lectin conjugate-directed gene transfer to airway epithelial cells.many cell surface receptors contain covalently linked carbohydrates recognizable by lectins. this study examined the feasibility of using lectins as gene delivery vectors. polylysine (pl) and histone (his) conjugates of concanavalin a (con a), maackia amurensis agglutinin (maa), sambucus nigra agglutinin (sna), and wheat germ agglutinin (wga), were employed to deliver pcmvlacz to human airway epithelial cells (cft1). as compared to the control (= 1.0), the beta-galactosidase activities expressed ...19947999119
glycoform heterogeneity of porcine interferon-gamma expressed in sf9 cells.porcine interferon-gamma (sfpoifn-gamma) was expressed with high efficiency in spodoptera frugiperda (sf9) cells by means of the baculovirus expression system. up to 10(5) u/ml of antivirally active sfpoifn-gamma could be tracked down in the culture medium at 64 h postinfection. three proteins (17, 19, and 21 kda), which under nondenaturing conditions primarily exist as mutual-dimeric combinations, were purified by immunoaffinity chromatography. carbohydrate labeling and kinetic deglycosylation ...19947999924
cytokine-induced beta-galactoside alpha-2,6-sialyltransferase in human endothelial cells mediates alpha 2,6-sialylation of adhesion molecules and cd22 ligands.sialic acids decorating blood and cell surface proteins can play important roles in various biological processes. the inflammatory cytokines tumor necrosis factor-alpha (tnf-alpha) and interleukin-1, as well as bacterial lipopolysaccharide, can activate vascular endothelium, increasing expression of several surface glycoproteins. here we show that treatment of cultured human endothelial cells (hec) with tnf-alpha, interleukin-1, or lipopolysaccharide causes increased expression of the enzyme bet ...19948144653
glycosylation pattern and enzyme activities in atrophic, angulated skeletal muscle fibres from ageing rats.in this study enzyme activities and lectin binding patterns in skeletal muscle from very old rats were investigated in order to evaluate changes in enzyme activity or carbohydrate expression in senile muscle. activities for adenosine triphosphatase (atpase), succinic dehydrogenase, non-specific esterase and the binding pattern for 31 lectins were investigated in the soleus muscles from very old (36 months) and young (3 months) rats. in ageing muscles atrophic, angulated muscle fibres are frequen ...19948186892
resistance to methotrexate is associated with selective changes of alpha 2,6- and alpha 2,3-sialyltransferase activities toward n-acetyllactosaminic sequences in human colon cancer cell line ht-29.in previous works we established that the alpha 2,6-sialyltransferase acting on n-acetyllactosaminic sequences [alpha 2,6(n)st, e.c. 2.4.99.1] behaves, in colonic cells, as an oncodevelopmentally regulated enzyme. subpopulations of the human colon cancer cell line ht-29 adapted to grow in 10(-5) m methotrexate (mtx), permanently retain the ability to differentiate as mucus-secreting cells when kept confluent for extended periods of time [lesuffleur et al. (1991) j. cell biol. 115, 1409-1418]. in ...19938240348
differences in cell surface carbohydrates, and in laminin and fibronectin synthesis, between adherent and non-adherent ehrlich ascites tumor cells.differences in cell surface carbohydrates and in laminin and fibronectin synthesis between 2 ehrlich ascites tumor (eat) cell lines, the adherent and non-adherent eat cells, have been studied. the adherent eat (a-eat) cells grow in monolayer in vitro in the presence of fetal bovine serum. the classical, or non-adherent eat (na-eat), cells grow in suspension in ascites form in the peritoneal cavity of mice, and they do not adhere when cultured in vitro. both eat cell lines express surface glycopr ...19938253521
histochemical analysis of rat testicular glycoconjugates. 3. non-reducing terminal residues in seminiferous tubules.lectins of helix pomatia (hpa), glycine max (sba), vicia villosa (vva), dolichos biflorus (dba), ulex europaeus (uea-1), tetragonolobus purpureus (lta), griffonia simplicifolia (bsa-1b4), maclura pomifera (mpa), sambucus nigra (sna) and maackia amurensis (maa) were used to explore the distribution of saccharides characteristic of non-reducing termini of o- and n-linked glycoprotein glycans in the seminiferous tubules of rat testis. sialyl residues (both alpha 2,3- and alpha 2,6-linked, as shown ...19938282567
staining of pancreatic centroacinar cells, liver bile canaliculi and testicular leydig cells with a monoclonal antibody against adrenocortical cells.the immunoreactivity of a monoclonal antibody against cell suspensions from guinea pig adrenal glands was examined at light- and electron-microscopic levels. in addition to the cell surface membrane of adrenocortical cells, the antibody labeled specific sites in the pancreas, liver and testis, but did not label any of the other tissues examined. in the pancreas, microvilli-like processes and the cell surface membrane of centroacinar cells were immunoreactive to the antibody. the microvilli of in ...19938339317
an in vitro adherence assay reveals that helicobacter pylori exhibits cell lineage-specific tropism in the human gastric epithelium.helicobacter pylori is a microaerophilic bacterium found in the stomach of asymptomatic humans as well as patients with acid peptic disease and gastric adenocarcinoma. we have developed an in situ adherence assay to examine the cell lineage-specific nature of binding of this organism and to characterize the nature of cell surface receptors that recognize its adhesin. fluorescein isothiocyanate-labeled h. pylori strains were bound to surface mucous cells present in the pit region of human and rat ...19938383333
isolation and partial characterization of nigrin b, a non-toxic novel type 2 ribosome-inactivating protein from the bark of sambucus nigra l.the bark of sambucus nigra l. contains a non-toxic novel type 2 ribosome-inactivating protein that we named nigrin b. in vitro, nigrin b strongly inhibited mammalian protein synthesis but did not affect plant nor bacterial protein synthesis. the protein (m(r) 58,000) contains two subunits, a (m(r) 26,000) and b (m(r) 32,000); linked by disulphide bridge(s). nigrin b was found to be an rrna n-glycosidase of the rrna of intact mammalian ribosomes and shares a very good n-terminal amino-acid sequen ...19938400135
characterization of the non-sulphated highly anionic kurloff cell glycoconjugates by lectin- and immunoblotting: evidence for the presence of alpha (2,8)-linked polysialic acid-bearing molecules.urea or guanidine hydrochloride-soluble extracts from highly purified kurloff cells (kc) radiolabelled in vitro were subjected to deae-cellulose chromatography. among the three anionic peaks obtained, a major and non-sulphated peak (designated as peak iv) strongly affected by glucosamine-labelling and eluted at about 0.3 m nacl was analyzed. gel filtration on sepharose cl4b and 10% sds-page indicated its heterogeneous size. peak iv consisted mainly of n-glycans as shown by its susceptibility to ...19938401292
selective inhibition of n-acetylglucosamine and galactose-specific lectins including the 14-kda vertebrate lectin by novel synthetic biantennary oligosaccharides.a novel series of synthetic biantennary tri-, penta- and hepta-saccharides with terminal beta-glcnac, beta-lacnac and alpha neuac(2,6)beta lacnac residues, respectively, [lacnac = gal beta (1,4)glc-nac] connected to a core gal residue were evaluated for their inhibitory potencies for specific plant and animal lectins. six isomeric trisaccharides with two beta-glcnac residues at the 2,3-, 2,4-, 2,6-, 3,4-, 3,6-, or 4,6-positions of the core gal were tested for their hemagglutination inhibition ac ...19938404897
production of a monoclonal antibody against cell-surface glycoprotein of guinea pig adrenocortical cells.a monoclonal antibody (mab) that reacted with the cell-surface antigens of adrenocortical cells was generated against cell suspensions from guinea pig adrenal glands. cell-surface membranes of the adrenocortical cells in all zones, i.e., zona glomerulosa, zona fasciculata, and zona reticularis, were labeled with the antibody. adrenal medulla remained unlabeled. immunoelectron microscopy showed that entire plasma membranes, i.e., plasma membranes between adjacent cells and free cell-surface membr ...19938419461
carbohydrate residues modulate the activation of coagulation factor x.factor x is a plasma protein involved in both the intrinsic and extrinsic pathways of blood coagulation. post-translational modifications of the protein involve gamma-carboxylation of specific glutamic acid residues, beta-hydroxylation of one aspartic acid residue, and n- and o-linked glycosylation. even though it is known that gamma-carboxylation is instrumental in regulating biological activity, the role of glycosylation in the function and properties of factor x has not been previously invest ...19938428982
glycoconjugates with neu5ac(alpha 2,6)gal(beta 1,4)glcnac sequences: a selective lectin-histochemical property of kurloff cells in guinea pig thymus.the kurloff cell (kc), a natural killer lymphocyte, contains a large (10-microns diameter) periodic acid-schiff (pas)-positive lysosome-like inclusion body called the kurloff body (kb), which exhibits strong acid phosphatase activity. the presence of sambucus nigra agglutinin (sna)-reactive neu5ac(alpha 2,6)-d-gal/gal-nac(beta 1,4)glcnac oligosaccharide sequences and the absence of the corresponding neu5ac(alpha 2,3) maackia amurensis agglutinin (maa)-reactive sequence in the major 35-kda n-glyc ...19938443837
sialylation of intestinal microvillar membranes in newborn, sucking and weaned pigs.affinity cytochemistry and biochemistry revealed distinctive temporal changes in the expression of sialylated and compositionally related membrane glycoconjugates in the pig small intestine between birth and weaning. the expression of membrane neuac alpha 2,6 moieties, recognized by sambucus nigra agglutinin-1, was high in newborn pigs, declined slightly during sucking and was very low in weaned animals. conversely, the expression of membrane neuac alpha 2.3 moieties, recognized by maackia amure ...19958563139
changes in the sialylglycoconjugate distribution on the human sperm surface during in-vitro capacitation: partial purification of a 20 kda sialylglycoprotein of capacitated spermatozoa.changes in the distribution of sialylglycoconjugates on the surface of uncapacitated and in-vitro capacitated human spermatozoa were studied by means of two sialic acid specific lectins (maackia amurensis agglutinin and sambucus nigra agglutinin). on the uncapacitated sperm surface, sialylglycoconjugates were found to be localized from the post-acrosomal region of the sperm head to the tail middle piece, whereas after in-vitro capacitation these molecules were only found in a small area of the p ...19958567809
sialic acid-binding lectins: submolecular specificity and interaction with sialoglycoproteins and tumour cells.we examined the specificity of limulin, limax flavus agglutinin (lfa) and sambucus nigra agglutinin i (sna i) at the submolecular level of sialic acid, and characterized their interactions with a panel of structurally distinct sialoglycoproteins. in haemagglutination inhibition assays neuac-alpha-glycosides were stronger inhibitors for limulin and lfa than native n-acetylneuraminic acid (neuac). the n-acetyl of neuac was crucial for binding to both lectins. n-thioacetylated neuac lost affinity f ...19958595263
the neuac(alpha-2,6)-gal/galnac-binding lectin from elderberry (sambucus nigra) bark, a type-2 ribosome-inactivating protein with an unusual specificity and structure.the cdna encoding the neuac(alpha-2,6)gal/galnac binding lectin from elderberry (sambucus nigra) bark (snai) was isolated from a cdna library constructed with mrna from the bark. sequence analysis of this lectin cdna revealed a striking similarity to the previously sequenced type-2 ribosome-inactivating proteins from ricinus communis and abrus precatorius. molecular modelling of snai further indicated that its structure closely resembles that of ricin. since snai strongly inhibits cell-free prot ...19968631319
characterization of terminal sialic acid linkages on human thymocytes. correlation between lectin-binding phenotype and sialyltransferase expression.t cell surface sialylation changes during maturation in the thymus. we have previously demonstrated increased expression of mrna encoding the gal beta 1, 3galnac alpha 2,3-sialyltransferase in mature medullary human thymocytes, compared with immature cortical thymocytes. for this enzyme, increased expression of transferase mrna correlated with increased sialylation of o-glycans. we have now examined the pattern of expression in the human thymus of two additional sialyltransferases, the gal beta ...19968631891
characterization and molecular cloning of sambucus nigra agglutinin v (nigrin b), a galnac-specific type-2 ribosome-inactivating protein from the bark of elderberry (sambucus nigra).the molecular structure of the sambucus nigra agglutinin v (snav), which has been described previously as a type-2 ribosome-inactivating protein called nigrin b, has been studied in detail by analysis of the purified protein combined with cdna cloning and molecular modelling. native snav is a dimer of two [a-s-s-b] pairs. hapten inhibition assays indicated that galnac is a 20-fold more potent inhibitor of snav than gal. a cdna clone encoding snav was isolated from a cdna library constructed with ...19968647092
a non-toxic two-chain ribosome-inactivating protein co-exists with a structure-related monomeric lectin (sna iii) in elder (sambucus nigra) fruits. 19968670129
decidual sialylation shows species-specific differences in the pregnant mouse and rat.biotinylated lectins from sambucus nigra (sna) and maackia amurensis (maa), which bind to alpha 2,6-linked and alpha 2,3-linked sialyl residues, respectively, were used as probes to study glycan terminal modifications associated with decidualization in the uterine stroma of pregnant rats and mice. binding of lectins from erythrina cristagalli (eca), phaseolus vulgaris (leukoagglutinin, l-pha), triticum vulgaris (wga) and bandeiraea simplicifolia (bsa-1b4) was also examined. tissues from rats bet ...19968699407
the expression of cmp-neuac: gal beta 1,4glcnac alpha 2,6 sialyltransferase [ec 2.4.99.1] and glycoproteins bearing alpha 2,6-linked sialic acids in human brain tumours.the expression of cmp-neuac: gal beta 1,4glcnac alpha 2,6 sialyltransferase (alpha 2,6-st) [ec 2.4.99.1] and glycoproteins bearing alpha 2,6-linked sialic acids were examined in primary human brain tumours and cell lines. 79% (19/24) of the meningiomas expressed alpha 2,6-st mrna, 42% (10/24) of which showed very high expression. alpha 2,6-st mrna expression was undetectable in normal brain tissue. in contrast, only 1/13 of the gliomas examined expressed detectable alpha 2,6-st mrna. metastases ...19958748163
differentiation -dependent expression of human beta-galactoside alpha 2,6-sialyltransferase mrna in colon carcinoma caco-2 cells.we have previously documented a dramatic elevation in the activity of alpha 2,6-sialytransferase towards gal beta 1,4glcnac (ec 2.4.99.1) (alpha 2,6st) in caco-2 cells maintained in culture for several days after confluence to elicit a high degree of enterocytic differentiation phenotype. northern analysis performed with a probe complementary to a region of human alpha 2,6st mrna common to all known transcripts demonstrated that the expression of alpha 2,6st mrna in caco-2 cells increased with t ...19968785482
glycoconjugates of the human trabecular meshwork: a lectin histochemical study.twelve specimens of resin-embedded human trabecular meshwork were probed with a panel of 21 biotinylated lectins, using an avidin-biotin peroxidase revealing system, in order to determine the normal pattern of saccharide expression in this tissue. high-mannose, intermediate and hybrid n-linked glycans, and complex n-linked bisected and non-bisected bi/tri-antennate glycans, as shown by the binding of canavalia ensiformis (cona), pisum sativum (psa), lens culinaris (lca) agglutinins and phaseolus ...19958787965
purification and basic characteristics of sialidase from tritrichomonas mobilensis.sialidase, produced by tritrichomonas mobilensis, a colonic parasite of squirrel monkeys, was purified by adsorption on human rbcs in ice-cold culture supernatant followed by release in pbs at 37 degrees c. the enzyme was purified by size-exclusion chromatography of rbc-eluted material giving a single peak with sialidase activity of molecular weight approx. 630 kda, representing a quadrimer of the complex of three subunits. sds-page under reducing conditions showed three bands of 56, 61, and 66 ...19958824674
changes of glycoprotein patterns in sera of humans under stress.stress exhibits adverse effects on many vital processes in which glycoproteins play a significant role(e.g. cell-cell/matrix interactions, immune response, neoplastic growth, implantation, prenatal development), yet only scarce attention has been directed towards studying stress induced changes in glycoprotein patterns. using sds-electrophoresis, blotting and digoxigenin-labelled lectins (sambucus nigra agglutinin, galanthus nivalis agglutinin, datura stramonium agglutinin, maackia amurensis agg ...19968833640
the expression of gal beta 1,4glcnac alpha 2,6 sialyltransferase and alpha 2,6-linked sialoglycoconjugates in human brain tumors.cmp-neuac: gal beta 1,4glcnac alpha 2,6 sialyltransferase (alpha 2,6-st) [ec 2.4.99.1] is developmentally regulated, shows a high degree of tissue specificity, and appears to play a role in oncogenic transformation and metastasis. in the present study, we have performed the first detailed analysis of the expression of alpha 2,6-st and alpha 2,6-linked sialoglycoconjugates in human brain tumors. we used a polyclonal, monospecific anti-rat alpha 2,6-st antibody and the alpha 2,6-linked sialic acid ...19968834541
analysis of different glycosylation states in igg subclasses.altered igg glycosylation affects certain immunological activities of human igg. enzyme-linked lectin assays (ella) were developed for detecting the glycosylation on igg and its individual subclasses in sera from healthy controls. biotinylated sambucus nigra, ricinus communis agglutinin i and bandeiraea simplicifolia ii were used to detect the terminal sialic acid (sa), galactose (gal) and n-acetylglucosamine (glcnac) sugar residues, respectively on the captured igg. a mild oxidation step of the ...19968853562
role of capsular sialic acid in virulence and resistance to phagocytosis of streptococcus suis capsular type 2.streptococcus suis capsular type 2 has a capsule rich in sialic acid (nana). sialic acid, known to be an antiphagocytic factor for many bacterial species, inhibits the activation of the alternative complement pathway. the role of capsular nana in virulence, resistance to phagocytosis and intracellular survival of s. suis capsular type 2 was evaluated. in general, a low concentration of nana was observed for all the s. suis strains tested. in addition, no difference could be found in nana concent ...19968856318
constitutively hyposialylated human t-lymphocyte clones in the tn-syndrome: binding characteristics of plant and animal lectins.previously, beta 1,3-galactosyltransferase-deficient (tn+) and normal (tf+) t-lymphocyte clones have been established from a patient suffering from tn-syndrome [thurnher et al. (1992) eur j immunol 22: 1835-42]. tn+ t lymphocytes express only tn antigen galnac alpha 1-o-r) while other o-glycan structures such as sialosyl-tn (neu5ac alpha 2,6galnac alpha 1-o-r) or tf (gal beta 1-3galnac alpha 1-o-r) antigens are absent from these cells as shown by flow cytometry using specific mabs for tf and sia ...19968872113
lectin-binding assays for the isoforms of human erythropoietin: comparison of urinary and four recombinant erythropoietins.assays have been developed for the isoforms of erythropoietin (epo) based on their binding to eight different lectins. these assays were used to compare the isoform compositions of two preparations of human urinary epo (uepo) and four preparations of recombinant dna-derived human epo (repo), which had been shown to differ in their biological and immunological properties and in their isoform composition as judged by isoelectric focusing and electrophoresis. agarose-bound ricinus communis agglutin ...19968882159
further characterization of ige-binding antigens in horse dander, with particular emphasis on glycoprotein allergens.ige-binding components in an extract of horse dander were analyzed, especially with regard to the glycoprotein allergens. after sds-page under reducing conditions and blotting, several of the glycoprotein ige-binding components, including two distinct bands of 27 and 31 kda, were detected. together with several other bands, they were shown to bind to the lectins sambucus nigra agglutinin (sna) and datura stramonium agglutinin (dsa), indicating terminal sialic acid linked alpha 2 --> 6 to galacto ...19968899112
structure and macromolecular composition of the zebrafish egg chorion.the chorion is the acellular envelope surrounding mature eggs of teleostean fish. the macromolecular composition of the zebrafish (danio rerio) egg chorion, organised as a three-layered structure, has been analysed. sds-page analysis, under reducing conditions, of isolated and purified chorions revealed a reproducible pattern of four major polypeptides (116, 97, 50 and 43 kda) and several minor bands. lectin binding assays showed that both the 116 kda and 50 kda proteins were recognised by conca ...19968913023
lectins and antibodies against blood-group antigens as tools for studying the cellular source of glycoproteins in human bronchial fluid: a comparison of morphological and biochemical observations.we used nine lectins and three antibodies directed against abo blood-group antigens in morphological and western-blot experiments to investigate the source of secretory products of human large airways. in tissue sections, the lectins from griffonia simplicifolia (type i b4), dolichos biflorus, and helix pomatia, and the antibodies to the a, b, and/or h-antigen bound to mucous gland cells and to goblet cells; the binding of these substances was dependent on secretor status and abo blood group. th ...19968929348
effects of metabolic inhibitors and lectins on the menadione-dependent generation of h2o2 by rat thymocytes.the capacity of oxidative metabolism and its regulation is an important factor in disease control. using scopoletin as a fluorescent substrate of peroxidase the extent of menadione-dependent production of h2o2 by rat thymocytes was determined. the reaction was inhibited by 2,4-dinitrophenol, papaverine, nordihydroguaiaretic acid and iodacetamide. the membrane-penetrating sh reagent n-ethylmaleimide primed the reaction, probably due to an inhibition of glutathione peroxidase. to delineate an infl ...19968988326
receptor specificity of influenza a viruses correlates with the agglutination of erythrocytes from different animal species.despite their uniform ability to bind to oligosaccharide-containing terminal sialic acids, influenza a viruses show differences in receptor specificity. to test whether agglutination of erythrocytes from different animal species could be used to assess the receptor specificity of influenza a viruses, we determined the agglutinating activities of a range of virus strains, including those with known receptor specificities, using erythrocytes from seven animal species. all equine and avian viruses, ...19979018149
identification of 45 kd antigen in immune complexes of patients of allergic bronchopulmonary aspergillosis.a glycoprotein antigen with an apparent mw of 45 kd was observed to be predominant in the circulating immune complexes isolated from patients of allergic bronchopulmonary aspergillosis as well as in the immune complexes prepared in vitro. further characterisation of 45 kd antigen with trypsin showed four immunologically active peptides with mw 43, 36, 33 and 16 kd. carbohydrate characterization using various lectins (maackia amurensis agglutinin, sambucus nigra agglutinin, peanut agglutinin, gal ...19979046027
colon carcinoma glycoproteins carrying alpha 2,6-linked sialic acid reactive with sambucus nigra agglutinin are not constitutively expressed in normal human colon mucosa and are distinct from sialyl-tn antigen.in human colon carcinoma, increased amounts of sialic acids have been found and correlated with tumor progression. further, the degree of o-acetylation of sialic acid residues in normal mucosa is higher than in colon carcinoma. thus, tumor-associated sialylated antigens may be constitutively expressed in o-acetylated form in normal mucosa unreactive with the respective monoclonal antibodies. we have earlier demonstrated a colon carcinoma-associated expression of alpha 2,6-linked sialic acid resi ...19979052758
sialic acid expression in normal and diseased human kidney.three sialic acid-specific lectins, tritrichomonas mobilensis (tml) (without linkage preference), maackia amurensis leukoagglutinin (mal) (alpha2,3) and sambucus nigra agglutinin (alpha2,6 linkage-specific), were used for detection of sialylated glycoconjugates in normal and diseased human kidneys. normal kidneys demonstrated strong podocyte positivity of alpha2,3 linked sialic acid and weaker sialic acid expression on capillary endothelium, which was alpha2,6 linked. renal biopsies (45) represe ...19969054191
differences in sialic acid-galactose linkages in the chicken egg amnion and allantois influence human influenza virus receptor specificity and variant selection.human influenza viruses are more efficiently isolated by inoculating patient samples into the amniotic rather than the allantoic cavity of embryonated chicken eggs. this type of cultivation selects virus variants with mutations around the hemagglutinin (ha) receptor binding site. to understand the molecular basis of these phenomena, we investigated the abundances of sialic acid (sa) linked to galactose (gal) by the alpha-2,3 linkage (sa alpha2,3gal) and sa alpha2,6gal in egg amniotic and allanto ...19979060710
changes in lectin binding sites during early human liver development.in this study we investigated whether changes in glycosylation during liver morphogenesis correlate with the early development of individual structures in the human liver. therefore, we localized the binding of the lectins from sambucus nigra (sna; specific for sialic acid), triticum vulgare (wga; specific for n-acetylglucosamine and sialic acid), ricinus communis (rca i; specific for beta-galactose), lotus tetragonolobus (lta; specific for alpha-fucose) and concanavalia ensiformis (con a; speci ...19979105893
increased ventricular sialylation in patients with heart failure secondary to ischemic heart disease.elevated serum sialic acids are associated with increased cardiovascular mortality, but sialic acid levels have not been studied in cardiac tissue.19979134277
purification and characterization of cathepsin d from normal human breast tissue.the lysosomal aspartyl protease cathepsin d is present in most mammalian cells and is active in the catabolism of intracellular and endocytosed proteins. it appears to be overexpressed and abnormally secreted in breast cancer cells, and may contribute to the process of tumor metastasis. in the present study, cathepsin d was purified 4500-fold from normal human breast tissue using pepstatin-agarose, deae sephadex, and sephadex g-75 chromatography. the resulting enzyme on sds-page contained five p ...19979155088
expression of beta-galactoside alpha 2,6-sialyltransferase does not alter the susceptibility of human colon cancer cells to nk-mediated cell lysis.the extent of processing of n-linked oligosaccharides and the sialylation of the target cell membranes has been positively correlated with resistance to lysis mediated by nk cells, but a conclusive evidence has never been reached. colon cancer tissues express an increased activity of beta-galactoside alpha 2,6-sialyltransferase (ec 2.4.99.1, alpha 2,6st), which catalyzed the addition of sialic acid in alpha 2,6-linkage to gal beta 1,4glcnac (n-acetyllactosamine) sequences of glycoprotein n-linke ...19979184831
ribosome-inactivating lectins with polynucleotide:adenosine glycosidase activity.lectins from aegopodium podagraria (apa), bryonia dioica (bda), galanthus nivalis (gna), iris hybrid (ira) and sambucus nigra (snai), and a new lectin-related protein from sambucus nigra (snlrp) were studied to ascertain whether they had the properties of ribosome-inactivating proteins (rip). ira and snlrp inhibited protein synthesis by a cell-free system and, at much higher concentrations, by cells and had polynucleotide:adenosine glycosidase activity, thus behaving like non-toxic type 2 (two c ...19979188793
presence of vicia graminea lectin- and vicia unijuga lectin-binding (vgu) glycoprotein in human amniotic fluid and some of its chemical and serological properties.vicia graminea- and vicia unijuga-binding glycoprotein (vgu glycoprotein) has been reported as a malignant tumor-associated antigen, which is found in various kinds of malignant tumor-tissues and ascitic and cyst fluids of malignant tumor patients, but not found in 20 kinds of normal human tissues. the glycoprotein reacts with anti-n lectins of vicia-graminea (vga) and vicia unijuga (vua), but does not react with anti-blood group m and n sera. the existence of vgu glycoprotein in human amniotic ...19979202424
Displaying items 1 - 100 of 402