scholarly journals Lectin receptors as markers for Trypanosoma cruzi. Developmental stages and a study of the interaction of wheat germ agglutinin with sialic acid residues on epimastigote cells.

1980 ◽  
Vol 152 (5) ◽  
pp. 1375-1392 ◽  
Author(s):  
M E Pereira ◽  
M A Loures ◽  
F Villalta ◽  
A F Andrade
Keyword(s):  
Sialic Acid ◽  
Cell Surface ◽  
Trypanosoma Cruzi ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Lectin Binding ◽  
The Other ◽  
Con A ◽  
Bauhinia Purpurea ◽  
Binding Lectin

Trypanosoma cruzi at various stages of maturation and differentiation have been isolated by conventional cellular fractionation procedures and characterized by cell surface markers using 30 highly purified lectins encompassing all known sugar specificities. Cell surface carbohydrates of the various T. cruzi stages were analyzed by agglutination and lectin-binding assays. Specific receptors for wheat germ agglutinin (WGA), Helix pomatia, Sophora japonica, and Bandeiraea simplicifolia lectin II were found only in culture epimastigotes, whereas peanut agglutinin (PNA) sites were present exclusively in amastigotes, those for Phaseolus vulgaris in bloodstream trypomastigotes and amastigotes, and for Wistaria floribunda hemagglutinin predominantly in culture forms of T. cruzi. The N-acetylgalactosamine (DGalNAc)-binding lectin from Bauhinia purpurea agglutinated and inhibited the movement of epimastigotes and bloodstream trypomastigotes, but it only inhibited--without agglutinating--culture trypomastigotes. Because both the agglutination and inhibition of movement were reversed by specific sugar haptens, Bauhinia purpurea sites were present in all the flagellated parasites. On the other hand, PNA sites were detectable on epimastigotes after the cells were treated with sialidase, whereas, at the same time, WGA receptors were completely removed and those for the other sialic acid-binding proteins, Aaptos papillata lectin II and Limulus polyphemus, were partially eliminated; moreover, the activity of Wistaria floribunda hemagglutinin, a DGalNAc-binding lectin, increased 4,000 times. Trypsinization and lyzozyme treatment of epimastigote cells did not significantly affect lectin agglutination or lectin binding. WGA reacted solely with sialic acid residues on epimastigote cell surface with an apparent association constant of 2 x 10(6) M-1, each epimastigote having an estimated average of 3 x 10(6) WGA sites, as determined by binding experiments and a minimum of 7.7 x 10(6) sialic acid residues, as calculated by colorimetric method after sialidase digestion. Evidences are presented that the sialyl residues are rapidly regenerated (in approximately 4 h) and that they, at least for the most part, are not adsorbed from the culture medium. The receptor for the D-mannose-binding lectins (concanavalin A [Con A] and Lens culinaris) must either be on the same carbohydrate moiety having the WGA site, or, if in a distinct molecule, both carrier molecules of Con A and WGA sites must be located close to each other in the plasma membrane of the parasite.

scholarly journals Studies on the cell surface of zoospores and cysts of the fungus Phytophthora cinnamomi: nature of the surface saccharides as determined by quantitative lectin binding studies.

1985 ◽  
Vol 33 (5) ◽  
pp. 384-388 ◽  
Author(s):  
A Bacic ◽  
M L Williams ◽  
A E Clarke
Keyword(s):  
Cell Surface ◽  
Concanavalin A ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Phytophthora Cinnamomi ◽  
Lectin Binding ◽  
Soybean Agglutinin ◽  
Binding Studies ◽  
Con A

The nature of the surface saccharides of zoospores, "partially encysted zoospores" and cysts of the root-rotting fungus Phytophthora cinnamomi, has been examined by quantitative lectin binding studies. Zoospores bound concanavalin A (Con A), but did not bind any of a variety of other lectins tested. In contrast, both cysts and "partially encysted zoospores" bound soybean agglutinin (SBA) as well as Con A. This indicates that accessible alpha-D-glucosyl/alpha-D-mannosyl-containing glycoconjugates predominate at the zoospore surface, whereas both alpha-D-glucosyl/alpha-D-mannosyl and galactosyl and/or N-acetyl-D-galactosaminosyl residues are accessible at the surface of cysts and "partially encysted zoospores." Neither Ulex europeus lectin nor wheat germ agglutinin (WGA) bound to any of the three cell preparations, indicating the absence of accessible alpha-L-fucosyl and N-acetyl-D-glucosaminosyl residues.

scholarly journals Differential involvement of cell surface sialic acid residues in wheat germ agglutinin binding to parental and wheat germ agglutinin-resistant Chinese hamster ovary cells.

1980 ◽  
Vol 85 (1) ◽  
pp. 60-69 ◽  
Author(s):  
P Stanley ◽  
T Sudo ◽  
J P Carver
Keyword(s):  
Sialic Acid ◽  
Cell Surface ◽  
Chinese Hamster Ovary ◽  
Cho Cells ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Chinese Hamster Ovary Cells ◽  
Chinese Hamster ◽  
Cho Cell ◽  
Differential Involvement

Two Chinese hamster ovary (CHO) cell mutants selected for resistance to wheat germ agglutinin (WGA) have been shown to exhibit defective sialylation of membrane glycoproteins and a membrane glycolipid, GM3. The mutants (termed WgaRII and WgaRIII) have been previously shown to belong to different genetic complementation groups and to exhibit different WGA-binding abilities. These mutants and a WGA-resistant CHO cell mutant termed WgaRI (which also possesses a surface sialylation defect arising from a deficient N-acetylglucosaminyltransferase activity), have enabled us to investigate the role of sialic acid in WGA binding at the cell surface. Scatchard plots of the binding of 125I-WGA (1 ng/ml to 1 mg/ml) to parental and WgaR CHO cells before and after a brief treatment with neuraminidase provide evidence for several different groups of sialic acid residues at the CHO cell surface which may be distinquished by their differential involvement in WGA binding to CHO cells.

scholarly journals Membrane glycoproteins of the nerve growth cone: diversity and growth regulation of oligosaccharides.

1986 ◽  
Vol 103 (4) ◽  
pp. 1369-1382 ◽  
Author(s):  
L M Greenberger ◽  
K H Pfenninger
Keyword(s):  
Sialic Acid ◽  
Growth Cone ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Growth Regulation ◽  
Binding Proteins ◽  
Ricinus Communis ◽  
Lectin Binding ◽  
Adult Brain ◽  
Two Dimensional

A subcellular fraction prepared from fetal rat brain and enriched in growth cone membranes is analyzed for its lectin-binding proteins. Growth-associated glycoproteins are identified by comparing the growth cone glycoproteins with those of synaptosomes. Protein was resolved in one- or two-dimensional gels, electroblotted, and blots probed with radioiodinated concanavalin A, wheat germ agglutinin, and Ricinus communis agglutinins I and II. In one-dimensional gels, each lectin recognizes approximately 20 polypeptides (with substantial overlap) most of which migrate diffusely and have relatively high molecular masses (range 30-200 kD). The seven major Coomassie-staining proteins of the membrane fraction (34-52 kD) are not the major lectin-binding proteins. In two-dimensional gels, the lectin-binding proteins are either streaked across the pH gradient or exist as multiple spots, indicating broad charge heterogeneity. Seven wheat germ agglutinin- and Ricinus communis agglutinin II-binding glycoproteins are present in greater abundance in growth cone fractions compared with synaptosomes. Most notably, an acidic, sialic acid-rich protein (27-30 kD, pI 4.0; termed gp27-30) is most abundant at postnatal day 4, but absent from adult brain. The protein's very acidic isoelectric point is due, at least in part, to its high sialic acid content. Growth regulation of specific protein-linked oligosaccharides suggests that they play a special role in growth cone function. In addition, the great diversity of growth cone glycoproteins from whole brain suggests glycoprotein heterogeneity among growth cones from different neuron types.

Lack of binding of serum glycoprotein hormone α subunit to Concanavalin A–Sepharose reflects increased branching of the oligosaccharide chains

1984 ◽  
Vol 103 (1) ◽  
pp. 111-116 ◽  
Author(s):  
A. J. Chapman ◽  
J. T. Gallagher ◽  
C. G. Beardwell ◽  
S. M. Shalet
Keyword(s):  
Concanavalin A ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Ricinus Communis ◽  
Lectin Binding ◽  
Pituitary Tumours ◽  
Con A ◽  
Glycoprotein Hormone ◽  
Α Subunit ◽  
Binding Forms

ABSTRACT The lectin-binding properties of serum α subunit were studied by lectin affinity chromatography. Normal individuals and most patients with pituitary tumours produced α subunit which bound specifically to Concanavalin A–Sepharose (Con A). Some patients with pituitary tumours produced both Con A-reactive α subunit and α subunit which did not bind to Con A. Concanavalin A–Sepharose-binding α subunit from all sources bound strongly to Ricinus communis agglutinin–Sepharose after treatment with neuraminidase. Serum α subunit from those patients with pituitary tumours, which did not bind to Con A, bound to wheat germ agglutinin–Sepharose, exhibiting both weakly binding and strongly binding forms. Serum α subunit from both patients and controls, which did bind to Con A, showed only weak affinity for wheat germ agglutinin–Sepharose. Neither the low affinity nor the high affinity of serum α subunit from any source for wheat germ agglutinin–Sepharose was affected by neuraminidase. These findings show that (a) the predominant pattern of glycosylation of serum α subunit from normal controls is a Con A-reactive, biantennate complex oligosaccharide and (b) that the structural alteration which results in serum α subunit which does not bind to Con A in some patients with pituitary tumours is not an absence of carbohydrate, rather the α subunit contains highly branched, either complex or hybrid oligosaccharides. J. Endocr. (1984) 103, 111–116

scholarly journals Sialic acid in mature megakaryocytes: detection by wheat germ agglutinin

Blood ◽  
1985 ◽  
Vol 65 (5) ◽  
pp. 1120-1126
Author(s):  
PK Schick ◽  
WG Jr Filmyer
Keyword(s):  
Sialic Acid ◽  
Guinea Pig ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Lectin Binding ◽  
Fluorescence Emission ◽  
Stage Iv ◽  
Computer Assisted ◽  
Chromomycin A3 ◽  
Vibrio Cholera

The characteristics of the surface of guinea pig megakaryocytes were investigated with wheat germ agglutinin (WGA). Purified guinea pig megakaryocytes and platelets were incubated with WGA conjugated with rhodamine, cytocentrifuged, and then exposed to Chromomycin A3 for the assessment of ploidy. The fluorescence emission of the DNA-Chromomycin complex was similar to that of fluorescein, and thus both rhodamine-WGA and Chromomycin A3 fluorescence could be analyzed in the same cell. Ploidy was assessed by microdensitometry of Chromomycin A3 fluorescence. Eight hundred megakaryocytes were analyzed by four parameters: (1) labeling by WGA, (2) ploidy, (3) morphological stage, and (4) size. The results were analyzed by a computer-assisted program. Although all platelets had reacted with WGA, only about half of the isolated megakaryocytes had been labeled by the lectin. The analysis of the megakaryocytes that had reacted revealed that 72% of stage III and 77% of stage IV megakaryocytes as compared with 35% of stage I and 29% of stage II cells had been labeled by the lectin. WGA reacted with 44% of 8N megakaryocytes and 60% and 59% of 16N and 32N cells. However, WGA labeling was independent of megakaryocyte size. The digestion of 15% and 48% of megakaryocyte sialic acid with neuraminidase from Vibrio cholera resulted in a 67% and 89% decrease in the binding of rhodamine- WGA, respectively, as determined by microdensitometry. The study indicated that sialic acid serves as a receptor for WGA and that sialoglycoproteins and possibly gangliosides become exposed on the surface of mature megakaryocytes. WGA can recognize mature megakaryocytes by biochemical criteria and the assessment of lectin binding could complement the morphological staging of megakaryocytes.

scholarly journals Sialic acid in mature megakaryocytes: detection by wheat germ agglutinin

Blood ◽  
1985 ◽  
Vol 65 (5) ◽  
pp. 1120-1126 ◽  
Author(s):  
PK Schick ◽  
WG Jr Filmyer
Keyword(s):  
Sialic Acid ◽  
Guinea Pig ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Lectin Binding ◽  
Fluorescence Emission ◽  
Stage Iv ◽  
Computer Assisted ◽  
Chromomycin A3 ◽  
Vibrio Cholera

Abstract The characteristics of the surface of guinea pig megakaryocytes were investigated with wheat germ agglutinin (WGA). Purified guinea pig megakaryocytes and platelets were incubated with WGA conjugated with rhodamine, cytocentrifuged, and then exposed to Chromomycin A3 for the assessment of ploidy. The fluorescence emission of the DNA-Chromomycin complex was similar to that of fluorescein, and thus both rhodamine-WGA and Chromomycin A3 fluorescence could be analyzed in the same cell. Ploidy was assessed by microdensitometry of Chromomycin A3 fluorescence. Eight hundred megakaryocytes were analyzed by four parameters: (1) labeling by WGA, (2) ploidy, (3) morphological stage, and (4) size. The results were analyzed by a computer-assisted program. Although all platelets had reacted with WGA, only about half of the isolated megakaryocytes had been labeled by the lectin. The analysis of the megakaryocytes that had reacted revealed that 72% of stage III and 77% of stage IV megakaryocytes as compared with 35% of stage I and 29% of stage II cells had been labeled by the lectin. WGA reacted with 44% of 8N megakaryocytes and 60% and 59% of 16N and 32N cells. However, WGA labeling was independent of megakaryocyte size. The digestion of 15% and 48% of megakaryocyte sialic acid with neuraminidase from Vibrio cholera resulted in a 67% and 89% decrease in the binding of rhodamine- WGA, respectively, as determined by microdensitometry. The study indicated that sialic acid serves as a receptor for WGA and that sialoglycoproteins and possibly gangliosides become exposed on the surface of mature megakaryocytes. WGA can recognize mature megakaryocytes by biochemical criteria and the assessment of lectin binding could complement the morphological staging of megakaryocytes.

scholarly journals The investigation of the changes in the surface glycoconjugates using two different spheroid models of breast cancer cells and availability assessment of these spheroid models for rapid diagnosis

2021 ◽  
Vol 38 (3) ◽  
pp. 266-271
Author(s):  
Yosun MATER ◽  
Günnur DEMİRCAN
Keyword(s):  
Breast Cancer ◽  
Cell Culture ◽  
Sialic Acid ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Sialic Acids ◽  
Maackia Amurensis ◽  
Maackia Amurensis Lectin

The importance of early cancer diagnosis has led to development of many different diagnostic methods. In this context, the studies investigating the presence and amount of sugar residues to use as indicators in the identification of cancer cell type have become prominent. In the present study, sialic acids found on the membrane surfaces of ER (+) MCF-7 and ER (-) MDA-MB-231 breast cancer cell lines were labeled using three-dimensional (3D) cell culture (Spheroid) model as the closest method to the patient sample, thus its natural environment, among the cell culture methods. These sugar units that play a role in regulation of important immune characteristics such as recognition, binding and metastasis were made visualizable by applying fluorescent-labeled lectins such as FITC-(Wheat Germ Agglutinin) specifically binding to sialic acid units (GlcNAc, Neu5Ac) including particularly ß-GlcNAc and FITC-(Maackia Amurensis-Lectin-1) specifically binding to Galß4GlcNAc type sialic acids. These glycan units were specifically labeled with FITC-(Maackia Amurensis-Lectin-1) and FITC- (Wheat Germ Agglutinin) and radiation intensities were analyzed relatively. The two different breast cancer cell cultures were compared with respect to change in the amounts of sialic acid residues containing α-2,3- and α-2,6 bonds using fluorescent-labeled lectins. In the present study, we have performed a precise, accurate and rapid determination of the sugar content in the different breast cancer cell surface lines by means of fluorescent-labeled lectins and carried out a relative comparison between the micrographs.

scholarly journals Concanavalin a and wheat germ agglutinin receptors on dictyostelium: Their visualization by scanning electron microscopy with microspheres

1976 ◽  
Vol 71 (1) ◽  
pp. 314-322 ◽  
Author(s):  
R Molday ◽  
R Jaffe ◽  
D McMahon
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Surface ◽  
Wheat Germ ◽  
Cellular Interactions ◽  
Con A ◽  
Stages Of Development ◽  
Lectin Receptors ◽  
Plant Lectins ◽  
Scanning Electron

The cellular slime mold, Dictyostelium discoideum, is a convenient model for studying cellular interactions during development. Evidence that specific cell surface components are involved in cellular interactions during its development has been obtained by Gerisch and co-workers (1, 2) using immunological techniques. Smart and Hynes (3) have shown that a cell surface protein can be iodinated on cells in aggregation phase, but not in vegetative phase, by the lactoperoxidase procedure. Recently, McMahon et al. (4), and Hoffman and McMahon have demonstrated, by SDS gel electrophoresis, considerable differences in cell surface proteins and glycoproteins of plasma membranes isolated from cells at different stages of development. Plant lectins have also been used to monitor changes in cell surface properties of D. discoideum cells during development. Weeks and co-workers (5, 6) have detected differences in the binding and agglutination of cells by concanavalin A (Con A). Gillette and Filosa (7) have shown that Con A inhibits cell aggregation and prematurely induces cyclic AMP phosphodiesterase. Capping of Con A receptors has also been reported (8). Reitherman et al. (9) have recently reported that agglutination of cells by several plant lectins and the slime mold agglutination, discoidin, changes during development. Such studies indicate that differences in surface properties exist for cells at various stages of development. However, owing to the uncertainties in the factors which contribute to lectin-induced cell agglutination (10), the molecular basis for these observations remain to be determined. In this study, we have used microspheres (11-14) coupled to either Con A or wheat germ agglutinin (WGA) as visual markers to study by scanning electron microscopy the topographical distribution of lectin receptors on D. discoideum cells fixed at different stages of development. We also describe the effect of labeling on the distribution of lectin receptors and on the morphology of the cell surface.

Sign in / Sign up

Export Citation Format

Share Document