scholarly journals Comparison of desialylation of rat transferrin by cellular and non-cellular methods

1989 ◽  
Vol 259 (2) ◽  
pp. 427-431 ◽  
Author(s):  
S Irie ◽  
J J Minguell ◽  
M Tavassoli
Keyword(s):  
Affinity Chromatography ◽  
Acid Hydrolysis ◽  
Ricinus Communis ◽  
Lectin Affinity Chromatography ◽  
Neuraminidase Treatment ◽  
Functional Studies ◽  
Lectin Affinity ◽  
Ricinus Communis Agglutinin ◽  
Protein Moiety

We have previously shown that the liver endothelium can desialylate the glycoprotein transferrin (Tf). In the present work we provide evidence that asialotransferrin obtained by this means behaves differently on Ricinus communis agglutinin (RCA120) lectin affinity chromatography from asialotransferrin obtained by either neuraminidase treatment or acid hydrolysis. Purified rat transferrin was radiolabelled either with 125I (protein moiety) or with 3H (sialyl residues), and subsequently saturated with iron. It was then passed through an RCA120-agarose column to isolate the fully sialylated component. Sialylated Tf was then desialylated either by incubation with purified rat liver endothelium or, in vitro, by neuraminidase treatment or by acid hydrolysis. The protein was again subjected to RCA120 column chromatography. Although both neuraminidase treatment and acid hydrolysis almost completely desialylated the glycoprotein (as evidenced by near absence of 3H label), the glycoprotein was not retained by the RCA120-agarose column. By contrast, liver endothelium partially desialylated the glycoprotein, but this desialylated fraction was retained by the RCA120-agarose column. These results suggest that desialylation with neuraminidase or acid hydrolysis may be inadequate for functional studies of asialotransferrin.

scholarly journals Assignment of laminin heavy chains using the lectin Ricinus communis agglutinin-1

1993 ◽  
Vol 295 (2) ◽  
pp. 537-541 ◽  
Author(s):  
J D F Wadsworth ◽  
A Okuno ◽  
P N Strong
Keyword(s):  
Skeletal Muscle ◽  
Smooth Muscle ◽  
Ricinus Communis ◽  
Lectin Affinity Chromatography ◽  
Native Form ◽  
Heavy Chains ◽  
Lectin Affinity ◽  
Ricinus Communis Agglutinin ◽  
A Chain ◽  
Binding Glycoprotein

Using high-resolution PAGE and Western-blotting techniques the lectin Ricinus communis agglutinin-1 (RCA-1) was tested for its ability to recognize laminin subunits from the mouse Engelbreth-Holm-Swarm (EHS) tumour and from bovine cardiac and skeletal muscle. Biotinylated RCA-1 recognized both the A and B chains of purified EHS-tumour laminin with a sensitivity comparable to anti-(EHS laminin) antibodies. In cardiac and skeletal muscle RCA-1 also recognized the B chains of laminin, together with a approximately 330 kDa RCA-1-binding glycoprotein that was undetectable in smooth muscle. This glycoprotein was not recognized by antibodies raised to laminin from the EHS tumour. Purification of the 330 kDa binding glycoprotein from skeletal muscle, using ion-exchange and lectin-affinity chromatography, revealed that in its native form, this glycoprotein is disulphide-bonded to the B chains of laminin. The demonstrated properties of the approximately 330 kDa RCA-1-binding glycoprotein are identical to those reported for the variant M chain of merosin which is known to replace the A chain in laminin from the extrasynaptic regions of skeletal muscle. These results establish that biotinylated RCA-1 can recognize A-, B- and M-chain subunits of laminin isoforms, and that, when used in conjunction with other techniques, they provide a useful method for the assignment of laminin heavy chains.

Lectin Affinity Chromatography of Rat Gonado Trophins in Vivo and in Vitro

1984 ◽  
Vol 67 (s9) ◽  
pp. 20P-20P
Author(s):  
A. J. Chapman ◽  
M. D. Wilson ◽  
S. Qizilbash
Keyword(s):  
Affinity Chromatography ◽  
Lectin Affinity Chromatography ◽  
Lectin Affinity

Activation energy and lectin affinity chromatography of gamma-glutamyltransferase as a marker for enzyme heterogeneity

1989 ◽  
Vol 22 (2) ◽  
pp. 115-119 ◽  
Author(s):  
Joris R. Delanghe ◽  
Marc L. De Buyzere ◽  
Ivan K. de Scheerder ◽  
Uwe Faust ◽  
Roger J. Wieme
Keyword(s):  
Activation Energy ◽  
Affinity Chromatography ◽  
Lectin Affinity Chromatography ◽  
Gamma Glutamyltransferase ◽  
Lectin Affinity ◽  
Enzyme Heterogeneity

Transferrin glycosylation in hypoxia

1991 ◽  
Vol 69 (4) ◽  
pp. 239-244 ◽  
Author(s):  
Erwin Regoeczi ◽  
J. Michael Kay ◽  
Paul A. Chindemi ◽  
Ouahida Zaimi ◽  
Kaye L. Suyama
Keyword(s):  
Affinity Chromatography ◽  
Sea Level ◽  
Anion Exchange ◽  
Immunoglobulin G ◽  
Lectin Affinity Chromatography ◽  
Lectin Affinity ◽  
Hypobaric Chamber

The aim of this study was to examine the effect of reduced O2 tension on the glycosylation of transferrin. Rats were placed in a hypobaric chamber (380 mmHg) that corresponded to an altitude of 5486 m above sea level for 21 days. The animals responded with marked increases in hematocrit (from 44 to 76%) and cardiac weight, and with reductions in the concentration of plasma transferrin averaging 15%. Analyses of their plasma transferrin by serial anion-exchange and lectin affinity chromatography revealed no changes in the extent of glycan branching. However, there was a moderate rise in the proportion of fucosylated transferrin molecules (fucosylation index) and a slight decrease in the transferrin fraction bearing a tetrasialylated biantennary glycan. The fucosylation index correlated positively with plasma transferrin concentrations in the test animals, but not in the controls. In contradistinction to the situation with transferrin, hypoxic rats exhibited a reduced fucosylation index of immunoglobulin G.Key words: fucosylation index, hypoxia, immunoglobulin G, lectin affinity chromatography, transferrin.

Antibodies Against Platelet Membrane Glycoproteins: Effect On Ristocetin-Induced Platelet Aggregation

1981 ◽  
Author(s):  
E F Ali-Briggs ◽  
C S P Jenkins ◽  
K J Clemetson
Keyword(s):  
Platelet Aggregation ◽  
Affinity Chromatography ◽  
Platelet Membrane ◽  
Receptor Activity ◽  
Free Medium ◽  
Membrane Glycoproteins ◽  
Lectin Affinity Chromatography ◽  
Lectin Affinity ◽  
Fab Fragments ◽  
Induced Aggregation

Some membrane glycoproteins (GPs) have been isolated by lectin-affinity chromatography and antibodies towards them have been raised. Platelets that have lost glycocalicin no longer respond to ristocetin-human VIII:WF, bovine VIIIR:WF, or to anti-glycocalicin or anti-GPs la and lb antibodies but are still agglutinated by anti-GPs lib and Ilia antibodies. Anti-GPs la and lb and anti-glycocalicin antibodies, IgG and Fab' fragments inhibited ristocetin- human VIIIR:WF- and bovine VIIIR:WF-induced aggregation of fixed, washed platelets and of platelets in plasma while anti-GPs Hb and Ilia antibodies were without effect.Crossed immunoelectrophorectic studies showed that glycocalicin was present on whole platelets in only trace amounts; anti-glycocalicin antibodies, however, recognized a slower migrating component. Platelets incubated in an EDTA-free medium no longer respond to ristocetin-human VIIIRrWF. Membranes isolated from such platelets contained glycocalicin which cross-reacted with a remnant of the slower migrating component. Anti-GPs la and lb antibodies gave more complex patterns but it was possible to identify the slower moving component recognized by the anti-glycocalicin antibodies.These results show that glycocalicin is not normally found as such on whole platelets but is present as a precursor which is most likely GP lb. On degradation of this precursor, glycocalicin is released from the membrane and VIIIRrWF-receptor activity is lost.

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