scholarly journals Mechanism of neutrophil chemiluminescence induced by wheat germ agglutinin: partial characterization of the antigens recognized by wheat germ agglutinin

Blood ◽  
1984 ◽  
Vol 64 (5) ◽  
pp. 1094-1102 ◽  
Author(s):  
Y Ozaki ◽  
J Iwata ◽  
T Ohashi

Abstract Wheat germ agglutinin (WGA) stimulated neutrophils to produce significant levels of luminol-dependent chemiluminescence (CL). Since WGA is known to bind N-acetylglucosamine (GlcNAc) oligomers and N- acetylneuraminic acid (NANA), we attempted to determine which binding property of WGA is essential for induction of CL. The succinylated form of WGA (SuWGA), which is no longer able to bind NANA, was still able to induce CL. N-Acetylglucosamine at a concentration of 20 mmol/L almost completely inhibited WGA-induced CL production by neutrophils, whereas bovine submaxillary gland mucin, a potent blocker of NANA binding of WGA, failed to inhibit CL production. Lectins with the GlcNAc-binding property were examined for their ability to induce CL. Those that have higher valences and have a tendency to bind GlcNAc oligomers in the internal portion of glycoconjugates were able to induce CL, whereas those that have low valences and bind terminal GlcNAc of glycoconjugates failed to induce CL even at high concentrations. Attempts were made to characterize the neutrophil membrane proteins recognized by WGA. Glycoproteins with a molecular weight of 25,000 daltons were identified by a 50 mmol/L GlcNAc elution of WGA gels loaded with 125I-labeled neutrophil membrane proteins. Elution with 500 mumol/L GlcNAc trimer produced several glycoproteins of different molecular weights in addition to the glycoproteins of 25,000 daltons. 125I-labeled WGA and SuWGA were used for autoradiographic analysis of cell extracts of the neutrophils separated on sodium dodecyl sulfate polyacrylamide gels. WGA recognized multiple glycoproteins of different molecular weights, whereas SuWGA bound only a few of them. Glycoproteins of 25,000 daltons, probably corresponding to those identified by 50 mmol/L GlcNAc elution, were also recognized.

Blood ◽  
1984 ◽  
Vol 64 (5) ◽  
pp. 1094-1102
Author(s):  
Y Ozaki ◽  
J Iwata ◽  
T Ohashi

Wheat germ agglutinin (WGA) stimulated neutrophils to produce significant levels of luminol-dependent chemiluminescence (CL). Since WGA is known to bind N-acetylglucosamine (GlcNAc) oligomers and N- acetylneuraminic acid (NANA), we attempted to determine which binding property of WGA is essential for induction of CL. The succinylated form of WGA (SuWGA), which is no longer able to bind NANA, was still able to induce CL. N-Acetylglucosamine at a concentration of 20 mmol/L almost completely inhibited WGA-induced CL production by neutrophils, whereas bovine submaxillary gland mucin, a potent blocker of NANA binding of WGA, failed to inhibit CL production. Lectins with the GlcNAc-binding property were examined for their ability to induce CL. Those that have higher valences and have a tendency to bind GlcNAc oligomers in the internal portion of glycoconjugates were able to induce CL, whereas those that have low valences and bind terminal GlcNAc of glycoconjugates failed to induce CL even at high concentrations. Attempts were made to characterize the neutrophil membrane proteins recognized by WGA. Glycoproteins with a molecular weight of 25,000 daltons were identified by a 50 mmol/L GlcNAc elution of WGA gels loaded with 125I-labeled neutrophil membrane proteins. Elution with 500 mumol/L GlcNAc trimer produced several glycoproteins of different molecular weights in addition to the glycoproteins of 25,000 daltons. 125I-labeled WGA and SuWGA were used for autoradiographic analysis of cell extracts of the neutrophils separated on sodium dodecyl sulfate polyacrylamide gels. WGA recognized multiple glycoproteins of different molecular weights, whereas SuWGA bound only a few of them. Glycoproteins of 25,000 daltons, probably corresponding to those identified by 50 mmol/L GlcNAc elution, were also recognized.


1978 ◽  
Vol 79 (1) ◽  
pp. 132-137 ◽  
Author(s):  
G Mintz ◽  
L Glaser

After separation of whole proteins of chick neural retina by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS), a number of glycoproteins can be detected by staining the gels with 125I-labeled wheat germ agglutinin (WGA) and other lectins. The glycoprotein patterns show both quantitative and qualitative changes between days 7 and 13 of development. Some of these glycoproteins can be separated by chromatography on columns of insolubilized lectins. These observations suggest that purification of some of these glycoproteins identified by staining with radioactive lectins would yield retinal antigens which may be specific for developmental stage and cell type.


1981 ◽  
Vol 200 (1) ◽  
pp. 153-159 ◽  
Author(s):  
S Azhar ◽  
K M Menon

Pretreatment of ovarian cells with concanavalin A and wheat-germ agglutinin blocked the gonadotropin-induced cyclic AMP and progesterone responses and this effect was time- and concentration-dependent. Basal production of either cyclic AMP or progesterone, however, was not affected by treatment of cells with lectin. The effect of concanavalin A on gonadotropin-mediated cyclic AMP and progesterone responses was blocked by alpha-methyl D-mannoside and alpha-methyl d-glucoside. Similarly the inhibitory effect of wheat-germ agglutinin was reversed by N-acetyl-D-glucosamine. Pretreatment of ovarian cells with concanavalin A or wheat-germ agglutinin had no effect on protein synthesis in the ovary as monitored by [3H]proline incorporation studies. Concanavalin A and wheat-germ agglutinin did not affect steroid production in response to dibutyryl cyclic AMP and 8-bromo cyclic AMP, indicating that the inhibitory action of lectin was occurring at a step before cyclic AMP formation. Lectins specific for L-fucose, D-galactose and N-acetyl-D-galactosamine, gorse seed agglutinin, peanut agglutinin and Dolichos biflorus agglutinin respectively, did not interfere with gonadotropin-induced cyclic AMP and progesterone responses. The present studies suggest that gonadotropin receptors may be glycoprotein in nature or closely associated with glycoprotein structures with the carbohydrate chain containing N-acetyl-D-glucosamine, mannose and possibly N-acetylneuraminic acid.


2005 ◽  
Vol 4 (11) ◽  
pp. 1951-1958 ◽  
Author(s):  
Felix D. Bastida-Corcuera ◽  
Cheryl Y. Okumura ◽  
Angie Colocoussi ◽  
Patricia J. Johnson

ABSTRACT The extracellular human pathogen Trichomonas vaginalis is covered by a dense glycocalyx thought to play a role in host-parasite interactions. The main component of the glycocalyx is lipophosphoglycan (LPG), a polysaccharide anchored in the plasma membrane by inositol phosphoceramide. To study the role of LPG in trichomonads, we produced T. vaginalis LPG mutants by chemical mutagenesis and lectin selection and characterized them using morphological, biochemical, and functional assays. Two independently selected LPG mutants, with growth rates comparable to that of the wild-type (parent) strain, lost the ability to bind the lectins Ricinnus comunis agglutinin I (RCA120) and wheat germ agglutinin, indicating alterations in surface galactose and glucosamine residues. LPG isolated from mutants migrated faster than parent strain LPG on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggesting the mutants had shorter LPG molecules. Dionex high-performance anion exchange chromatography with pulsed amperometric detection analyses revealed galactosamine, glucosamine, galactose, glucose, mannose/xylose, and rhamnose as the main monosaccharides of T. vaginalis parent strain LPG. LPG from both mutants showed a reduction of galactose and glucosamine, corresponding with the reduced size of their LPG molecules and inability to bind the lectins RCA120 and wheat germ agglutinin. Mutant parasites were defective in attachment to plastic, a characteristic associated with avirulent strains of T. vaginalis. Moreover, the mutants were less adherent and less cytotoxic to human vaginal ectocervical cells in vitro than the parental strain. Finally, while parent strain LPG could inhibit the attachment of parent strain parasites to vaginal cells, LPG from either mutant could not inhibit attachment. These combined results demonstrate that T. vaginalis adherence to host cells is LPG mediated and that an altered LPG leads to reduced adherence and cytotoxicity of this parasite.


1976 ◽  
Vol 71 (2) ◽  
pp. 606-623 ◽  
Author(s):  
A Lernmark ◽  
A Nathans ◽  
D F Steiner

Methods have been developed for the isolation on a semi-micro scale of a plasma membrane-enriched fraction from rat islets of Langerhans. An important feature of these experiments is the use of 125I-labeled wheat germ agglutinin as a specific probe for plasma membrane-containing fractions. The partly purified plasma membrane fraction had a density in sucrose of about 1.10 and was enriched in the activities of 5'-nucleotidase, alkaline phosphatase, sodium-potassium, and magnesium-dependent ATPase and adenylate cyclase. It contained only very low levels of acid phosphatase, cytochrome c oxidase, insulin, and RNA. Further purification was hampered by the relatively small amounts of fresh plasma membrane material that could be obtained from 16-24 rats in each experiment. When islets were prelabeled with radioactive fucose, the plasma membrane-enriched fraction contained radioactivity at a four- to fivefold higher specific acivity than the whole islet homogenate. Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis of plasma membrane-enriched fractions pooled from several experiments revealed a distinctive pattern of protein bands as compared with other less pure fractions. With respect to rapidity, apparent specificity, and easy reversibility of the labeling of the plasma membrane fraction, 125I-wheat germ agglutinin provides a highly useful tool for the detection of microgram quantities of plasma membrane components which should be applicable to many other systems as well.


Blood ◽  
1996 ◽  
Vol 88 (1) ◽  
pp. 277-288 ◽  
Author(s):  
LJ Bendall ◽  
KF Bradstock ◽  
DJ Gottlieb

Abstract Adhesion of myeloid leukemia cells to the bone marrow (BM) microenvironment is mediated in part by Beta 1 and Beta 2 integrins. Cells of the erythroleukemia line K562, derived from a patient with chronic myeloid leukemia, bind to BM fibroblasts (BMFs) but the adhesion cannot be accounted for by integrins or other known adhesion proteins including CD44 or members of the Ig or selectin families. Membrane fragments from K562 cells were radioiodinated and allowed to adhere to BMF monolayers. Adherent proteins were solubilized together with the fibroblasts, analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and visualized by autoradiography. Four adherent proteins were consistently observed. Two of these, with reduced molecular weights of 52 kD and 35 to 37 kD, were prominent. Addition of soluble thrombospondin and heparin but not fibronectin inhibited binding of K562 membrane proteins to adherent BMFs and immobilized thrombospondin- and heparin-bound K562 proteins. The 52-kD protein has a multimeric structure nonreduced and has characteristics of a glycoprotein. Its adhesion to fibroblasts is divalent cation and temperature sensitive. The 35- to 37-kD protein, whose function is divalent cation but not temperature sensitive, is phosphoinositol- linked and has characteristics identical to an adherent 35- to 37-kD protein identified on murine progenitor cells. Membrane preparations from two cases of acute myeloid leukemia showed an adherent 35- to 37- kD protein and in one case an adherent 52-kD protein without other adherent bands. A K562 subclone with reduced adherence to BMFs showed reduced amounts of adherent 52-kD and 35- to 37-kD proteins. These proteins may be responsible for the adhesion of malignant and normal hematopoietic progenitor cells to the BM microenvironment.


2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Abraham Landa ◽  
Kaethe Willms ◽  
Juan Pedro Laclette

In order to explore how molecules are linked to the membrane surface in larvalTaenia solium, whole cysticerci were incubated in the presence of phospholipase C fromClostridium perfringens(PLC). Released material was collected and analyzed in polyacrylamide gels with sodium dodecyl sulfate. Two major bands with apparent molecular weights of 180 and 43 kDa were observed. Western blot of released material and localization assays in cysticerci tissue sections using antibodies against five known surface glycoproteins ofT. soliumcysticerci indicated that only one, previously called GP1, was released. Similar localization studies using the lectins wheat-germ-agglutinin and Concanavalin A showed that N-acetyl-D-glucosamine, N-acetylneuraminic, sialic acid,αmethyl-D-mannoside, D-manose/glucose, and N-acetyl-D-glucosamine residues are abundantly present on the surface. On the other hand, we find that treatment with PLC releases molecules from the surface; they do not reveal Cross Reacting Determinant (CRD), suggesting a novel anchor to the membrane for the glycoprotein GP1.


1991 ◽  
Vol 69 (7) ◽  
pp. 454-459 ◽  
Author(s):  
J. I. de Vicente ◽  
P. del Valle ◽  
F. Busto ◽  
D. de Arriaga ◽  
J. Soler

Mitochondrial F1-ATPase was purified from the mycelium of Phycomyces blakesleeanus NRRL 1555(−) and its kinetic characteristics were studied. Sodium dodecyl sulfate – polyacrylamide gel electrophoresis of the enzyme reveals five bands (α, β, γ, δ, and ε) characteristic of the F1 portion with apparent molecular weights of 60 000, 53 000, 31 000, 25 000, and 21 000, respectively. The molecular weight of the native F1-ATPase from Phycomyces blakesleeanus was in agreement with the stoichiometry α3 β3 γ δ ε. The MgATP complex is the true substrate for ATPase activity which has a Km value of 0.15 mM. High concentrations of free ATP or free Mg2+ ions inhibit the ATPase activity. ADP appears to act as a negative allosteric effector with regard to MgATP hydrolysis, with the apparent Vmax remaining unchanged.Key words: mitochondrial F1-ATPase, Phycomyces blakesleeanus, enzyme purification, kinetic properties.


1997 ◽  
Vol 110 (4) ◽  
pp. 409-420 ◽  
Author(s):  
M.W. Goldberg ◽  
C. Wiese ◽  
T.D. Allen ◽  
K.L. Wilson

We used field emission in-lens scanning electron microscopy to examine newly-assembled, growing nuclear envelopes in Xenopus egg extracts. Scattered among nuclear pore complexes were rare ‘dimples’ (outer membrane depressions, 5–35 nm diameter), more abundant holes (pores) with a variety of edge geometries (35–45 nm diameter; 3.3% of structures), pores containing one to eight triangular ‘star-ring’ subunits (2.1% of total), and more complicated structures. Neither mature complexes, nor these novel structures, formed when wheat germ agglutinin (which binds O-glycosylated nucleoporins) was added at high concentrations (>500 microg/ml) directly to the assembly reaction; low concentrations (10 microg/ml) had no effect. However at intermediate concentrations (50–100 microg/ml), wheat germ agglutinin caused a dramatic, sugar-reversible accumulation of ‘empty’ pores, and other structures; this effect correlated with the lectin-induced precipitation of a variable proportion of each major Xenopus wheat-germ-agglutinin-binding nucleoporin. Another inhibitor, dibromo-BAPTA (5,5′-dibromo-1,2-bis[o-aminophenoxylethane-N,N,N′,N′-tetraacetic acid), had different effects depending on its time of addition to the assembly reaction. When 1 mM dibromo-BAPTA was added at time zero, no pore-related structures formed. However, when dibromo-BAPTA was added to growing nuclei 40–45 minutes after initiating assembly, star-rings and other structures accumulated, suggesting that dibromo-BAPTA can inhibit multiple stages in pore complex assembly. We propose that assembly begins with the formation and stabilization of a hole (pore) through the nuclear envelope, and that dimples, pores, star-rings, and thin rings are structural intermediates in nuclear pore complex assembly.


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