Platelet Membrane Glycoproteins and their Possible Relationship to the ADP Mechanism of Platelet Aggregation

1975 ◽  
Author(s):  
D. R. Phillips ◽  
C. S. P. Jenkins ◽  
D. Meyer ◽  
M.-J. Larrieu ◽  
E. F. Luscher
Keyword(s):  
Platelet Aggregation ◽  
Surface Structure ◽  
Marked Reduction ◽  
Membrane Surface ◽  
Platelet Membrane ◽  
Membrane Glycoproteins ◽  
Altered Expression ◽  
Glanzmann’S Thrombasthenia ◽  
Glanzmann's Thrombasthenia ◽  
Induced Aggregation

Platelets isolated from patients with Glanzmann’s Thrombasthenia release in the presence of thrombin and other stimuli but fail to respond to ADP. Since the iutia.l interaction, between the platelet and ADP is at the membrane surface, it would appear that this surface lacks the necessary receptor for ADP. The surface structure of normal and thrombasthenia platelets was compared using the lactoperoxidase iodination technique. Iodination of normal platelets results in the labelling of four glycoproteins, I, IIa IIb and III, with relative ratios of 1 : 1 : 1 : 3 plus other non-characterised polypeptides. Thrombasthenic platelets similarly treated revealed a drastically altered expression of the glycoproteins on the membrane. The relative ratios (1.5: 1:0.4:0.5) revealed the decrease of glycoprotein IIb and the marked reduction of glycoprotein III. Arguments and data will be presented which point to the possibility that glycoprotein IIb is involved in ADP-induced aggregation.

ANTIBODIES AGAINST MEMBRANE GLYCOPROTEINS: AGGREGATION, CROSS IMMUNOELECTROPHORESIS STUDIES, AND RELEVANCE TO GLANZMANN’S THROMBASTHENIA

1981 ◽  
Author(s):  
C S P Jenkins ◽  
E F Ali-Briggs ◽  
K J Clemetson
Keyword(s):  
Platelet Aggregation ◽  
Marked Reduction ◽  
Membrane Glycoproteins ◽  
Clot Retraction ◽  
Glanzmann’S Thrombasthenia ◽  
Crossed Immunoelectrophoresis ◽  
Glanzmann's Thrombasthenia ◽  
Triton X ◽  
Induced Aggregation ◽  
Second Wave

In Glanzmann’s thrombasthenia, glycoproteins (GPs) IIb and IIIa are missing or strongly reduced in concentration and aggregation to ADP, collagen and thrombin is impaired. Antibodies against GPs IIb and IIIa did not entirely induce a thrombasthenia-like state in normal platelets; however they did strongly inhibit collagen-induced aggregation, inhibited the second wave of aggregation induced by ADP, inhibited to some extent thrombin-induced aggregation and clot retraction, and were totally without effect on ristocetin-human VIIIR:WF.Crossed immunoelectrophoresis studies using Triton X-100 extracts of whole platelets and platelet membranes with these antibodies gave a single immunoprecipitate. This immunoprecipitate was absent when similar studies were carried out with thrombasthenie platelets. Anti-whole platelets antibodies gave a number of immunoprecipitates with normal platelets and differences were observed with thrombasthenie platelets, the most notable of which was a marked reduction in one of the major immunoprecipitates.These results provide further evidence that GPs IIb and IIIa are involved in the later stages of platelet aggregation.

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.

scholarly journals Monocytes and platelets share the glycoproteins IIb and IIIa that are absent from both cells in Glanzmann's thrombasthenia type I

1983 ◽  
Vol 214 (2) ◽  
pp. 331-337 ◽  
Author(s):  
G Gogstad ◽  
Ø Hetland ◽  
N O Solum ◽  
H Prydz
Keyword(s):  
Platelet Membrane ◽  
Type I ◽  
Membrane Glycoproteins ◽  
Edta Treatment ◽  
Glanzmann’S Thrombasthenia ◽  
Glanzmann's Thrombasthenia

By means of an antiserum specific to the complex of the platelet membrane glycoproteins IIb and IIIa we demonstrate here that monocytes and purified monocyte membranes share these glycoproteins with platelets. The monocyte glycoprotein IIb-IIIa complex showed complete immunological identity with the platelet counterpart and, furthermore, dissociated after EDTA treatment exactly as did the platelet complex. In Glanzmann's thrombasthenia type I, monocytes as well as platelets lack this antigen completely.

Crossed Immunoelectrophoresis In The Identification Of Platelet Membrane Glycoproteins And Complexes

1981 ◽  
Author(s):  
S Karpatkin ◽  
S Shulman ◽  
L Howard ◽  
S Sadanandan
Keyword(s):  
Concanavalin A ◽  
Surface Antigens ◽  
Platelet Membrane ◽  
Surface Proteins ◽  
Membrane Glycoproteins ◽  
Glanzmann’S Thrombasthenia ◽  
Crossed Immunoelectrophoresis ◽  
Platelet Membranes ◽  
Glanzmann's Thrombasthenia ◽  
Major Antigen

Human platelet membranes were solubilized in 1% Triton X-100 and subjected to crossed immunoelectrophoresis, employing a rabbit anti-piatelet membrane antibody. Ten different antigens were observed fairly consistently; one could be identified as albumin, the other as fibrinogen. Surface antigens were determined by antibody adsorbtion experiments, and cell surface labeling with 125I-lactoperoxidase. Four surface antigens reacted with concanavalin A, when this was employed as an intermediate spacer gel. A major surface antigen, 10, was present on all preparations and was inversely related to antigens 13 and 18, which moved more cathodally. Membranes from preparations with full 10 antigen peaks had absent or diminished 13 and 18 antigen peaks, whereas preparations with absent to incomplete cathodal curves had increased 13 and 18 antigen peaks. Digestion of intact washed platelets with α chymotrypsin resulted in a decrease in the 10 antigen peak and an increase in 13 and 18, suggesting a structural relationship. Extraction of platelet membranes in EDTA or EGTA resulted in the disappearance of 10 and appearance of 13 and 18 (which react with concanavalin A) and 15 and 16 (which do not). Splitting of the major antigen into 13, 18, 15 and 16 could be prevented by addition of excess Ca++ relative to EGTA (but not by excess Mg++). Similar results were obtained in the absence of chelating agents following dialysis at 60-200 hrs against ‘Ca++-free’ buffer. Five patients with Glanzmann’s thrombasthenia have been studied. All k components of the major membrane antigen are missing. We conclude that the major antigen, 10, is composed of 2 glycoproteins, 13 and 18, and 2 other surface proteins, 15 and 16, which are held together by Ca++. It is conceivable that patients with Glanzmann’s thrombasthenia are lacking a membrane receptor for Ca++ or the platelet membrane (glyco)protein which anchors these A components.

scholarly journals Residual amounts of glycoproteins IIb and IIIa may be present in the platelets of most patients with Glanzmann's thrombasthenia

Blood ◽  
1985 ◽  
Vol 65 (4) ◽  
pp. 1021-1024 ◽  
Author(s):  
AT Nurden ◽  
D Didry ◽  
N Kieffer ◽  
RP McEver
Keyword(s):  
Bleeding Disorder ◽  
Platelet Membrane ◽  
Type I ◽  
Membrane Glycoproteins ◽  
Glanzmann’S Thrombasthenia ◽  
Polyclonal Rabbit ◽  
Glanzmann's Thrombasthenia ◽  
Genes Encoding ◽  
Or Genes

Abstract Glanzmann's thrombasthenia is an inherited bleeding disorder characterized by abnormalities of platelet membrane glycoproteins (GP) IIb and IIIa. Most patients, usually designated as type I, have been reported to have undetectable levels of GP IIb and GP IIIa with the assay used. We have used polyclonal rabbit antibodies against GP IIb and GP IIIa in a sensitive immunoblot procedure capable of revealing trace amounts of these glycoproteins. Platelets from nine thrombasthenic patients, including seven with type I disease, were studied. GP IIIa, although decreased, was clearly detectable in platelets of eight patients and GP IIb was identified in five. Our findings suggest that residual quantities of GP IIb and GP IIIa are present in most patients with thrombasthenia and therefore that major deletions in the gene or genes encoding these proteins are uncommon.

scholarly journals Analysis of human platelet glycoproteins IIb-IIIa and Glanzmann's thrombasthenia in whole blood by flow cytometry

Blood ◽  
1986 ◽  
Vol 68 (1) ◽  
pp. 173-179
Author(s):  
LK Jennings ◽  
RA Ashmun ◽  
WC Wang ◽  
ME Dockter
Keyword(s):  
Flow Cytometry ◽  
Whole Blood ◽  
Human Platelet ◽  
Platelet Rich Plasma ◽  
Platelet Membrane ◽  
Parameter Analysis ◽  
Light Scatter ◽  
Membrane Glycoproteins ◽  
Glanzmann’S Thrombasthenia ◽  
Glanzmann's Thrombasthenia

Antibodies that bind to human platelet membrane glycoproteins IIb and IIIa were used to develop methods for analyzing platelet membrane components by flow cytometry. Platelets were tentatively identified by their low-intensity light scatter profiles in whole blood or platelet- rich plasma preparations. Identification of this cell population as platelets was verified by using platelet-specific antibodies and fluorescein-conjugated antiimmunoglobulin. Two-parameter analysis of light scatter versus fluorescence intensity identified greater than 98% of the cells in the “platelet” light scatter profile as platelets due to their acquired fluorescence. Both platelet-rich plasma and whole blood were used to study platelet membrane glycoproteins IIb and IIIa on a single cell basis in an unwashed system. Prostacycline was included in these preparations as a precautionary step to inhibit platelet aggregation during analysis. Flow cytometry is a successful technique for rapid detection of platelet membrane defects such as Glanzmann's thrombasthenia. Platelets from Glanzmann's thrombasthenic individuals were readily distinguished from platelets with normal levels of glycoprotein IIb and IIIa and from platelets with glycoprotein levels characteristic of heterozygote carriers of this disorder. This technique provides a sensitive tool for investigating platelet functional defects due to altered expression or deficiency of platelet surface proteins.

Inherited abnormalities of platelet glycoproteins

1981 ◽  
Vol 294 (1072) ◽  
pp. 281-290 ◽  
Keyword(s):  
Platelet Aggregation ◽  
Platelet Function ◽  
Membrane Glycoproteins ◽  
Blood Disorders ◽  
Glanzmann’S Thrombasthenia ◽  
Glanzmann's Thrombasthenia ◽  
Bernard Soulier Syndrome

Glanzmann’s thrombasthenia and the Bernard-Soulier syndrome are inherited blood disorders characterized by abnormalities in different aspects of platelet function during haemostasis. Platelets from patients with thrombasthenia do not aggregate in response to the normal physiological platelet aggregation inducing stimuli, while Bernard-Soulier platelets have a reduced capacity to adhere to exposed subendothelium. Deficiencies of different membrane glycoproteins have been located in the platelets of both disorders and suggest specific roles for membrane glycoproteins in different aspects of platelet function.

Antigenic Properties And Structure Of Membrane Glycoprotein Receptors

1981 ◽  
Author(s):  
T J Kunicki
Keyword(s):  
Platelet Aggregation ◽  
Platelet Adhesion ◽  
Membrane Glycoproteins ◽  
Glanzmann’S Thrombasthenia ◽  
Normal Platelet ◽  
Glanzmann's Thrombasthenia ◽  
Antigenic Properties ◽  
Normal Hemostasis ◽  
Triton X

Membrane glycoproteins (GP) IIb and IIIa are not detectable on the platelets of a majority (Type 1) of patients with Glanzmann’s thrombasthenia, a hereditary disorder of platelet function characterized by an absence of platelet-platelet adhesion. These platelets also do not express the human platelet alloantigen, PlA1, a finding which led to the demonstration that the PlA1 alloantigen is associated with GPIIIa, but not with GPIIb. Alloantibodies directed against the PlA1 determinant or certain other determinants associated with GPIIb and/or GPIIIa appear to be capable of inhibiting normal platelet- platelet adhesion, suggesting that these glycoproteins function as key mediators of this process, an obligate step in normal hemostasis. Subsequent studies have supported this hypothesis by demonstrating that fibrinogen, which is known to be a key cofactor in normal platelet aggregation, does not bind to thrombasthenic platelets.We have used crossed immunoelectrophoresis of Triton X-100 soluble membrane glycoproteins against a multispecific rabbit antibody to quantitate levels of GPIIb and GPIIIa on normal and thrombasthenic platelets and to study the interaction of these two glycoproteins in a soluble nondenatured state. These studies have provided information on 1) the inheritance of PlA1 and the glycoprotein IIb/IIIa defect in Glanzmann’s thrombasthenia, and 2) reversible Ca++-dependent changes in the orientation of GPIIb and GPIIIa, which may contribute to understanding of the function of these glycoproteins in normal platelet aggregation. In the presence of sufficient Ca++, glycoproteins IIb and IIIa were found to exist only in heterogenous complexes, whether within isolated membranes, or in solution. Chelation of Ca++ by EDTA or EGTA resulted in the dissociation of these glycoproteins; reassociation could be induced by readdition of excess Ca++.

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