Proteolytic degradation of von Willebrand factor after DDAVP administration in normal individuals

The infusion of 1-deamino-8-D-arginine vasopressin (DDAVP) in normal individuals is followed by an increase in factor VIII/von Willebrand factor (vWF) in plasma, by an increase in intensity of all sizes of multimers, and by the appearance of larger multimers of vWF than those seen in the resting state. Since the larger multimers are rapidly cleared and proteolysis is known to cause disaggregation of large multimers, we evaluated the degree of vWF proteolysis after DDAVP administration. DDAVP was infused into eight normal adult volunteers, and the relative proportions of the intact 225 kilodalton (kDa) subunit and the 189, 176, and 140 kDa vWF fragments were compared before and at different times after DDAVP infusion. The relative proportion of the 176 kDa fragment was increased, whereas that of the other species was decreased, thereby indicating that proteolytic fragmentation had occurred. However, plasmin did not appear to be responsible because the vWF fragments characteristically produced by this enzyme could not be detected. Concomitant analysis of vWF multimeric structure showed that these changes were accompanied by an increase in the relative proportion of the satellite bands, which suggests that they were proteolytically generated. Proteolysis may explain, at least in part, rapid clearance of larger vWF multimers released by DDAVP.

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Proteolytic degradation of von Willebrand factor after DDAVP administration in normal individuals

Blood ◽

10.1182/blood.v70.1.173.173 ◽

1987 ◽

Vol 70 (1) ◽

pp. 173-176 ◽

Cited By ~ 36

Author(s):

J Batlle ◽

MF Lopez-Fernandez ◽

A Lopez-Borrasca ◽

C Lopez-Berges ◽

JA Dent ◽

...

Keyword(s):

Von Willebrand Factor ◽

Resting State ◽

Relative Proportion ◽

The Other ◽

Proteolytic Degradation ◽

Normal Individuals ◽

Rapid Clearance ◽

Von Willebrand ◽

Willebrand Factor ◽

Adult Volunteers

Abstract The infusion of 1-deamino-8-D-arginine vasopressin (DDAVP) in normal individuals is followed by an increase in factor VIII/von Willebrand factor (vWF) in plasma, by an increase in intensity of all sizes of multimers, and by the appearance of larger multimers of vWF than those seen in the resting state. Since the larger multimers are rapidly cleared and proteolysis is known to cause disaggregation of large multimers, we evaluated the degree of vWF proteolysis after DDAVP administration. DDAVP was infused into eight normal adult volunteers, and the relative proportions of the intact 225 kilodalton (kDa) subunit and the 189, 176, and 140 kDa vWF fragments were compared before and at different times after DDAVP infusion. The relative proportion of the 176 kDa fragment was increased, whereas that of the other species was decreased, thereby indicating that proteolytic fragmentation had occurred. However, plasmin did not appear to be responsible because the vWF fragments characteristically produced by this enzyme could not be detected. Concomitant analysis of vWF multimeric structure showed that these changes were accompanied by an increase in the relative proportion of the satellite bands, which suggests that they were proteolytically generated. Proteolysis may explain, at least in part, rapid clearance of larger vWF multimers released by DDAVP.

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PROTEOLYTIC DEGRADATION OF VON WILLEBRAND FACTOR AFTER DDAVP ADMINISTRATION IN NORMAL INDIVIDUALS

10.1055/s-0038-1644121 ◽

1987 ◽

Author(s):

J Batlle ◽

M F López-Fernández ◽

C López-Berges ◽

S D Berkowitz ◽

Z M Ruggeri ◽

...

Keyword(s):

Von Willebrand Factor ◽

Resting State ◽

Relative Proportion ◽

The Other ◽

Proteolytic Degradation ◽

Normal Individuals ◽

Rapid Clearance ◽

Von Willebrand ◽

Willebrand Factor ◽

Adult Volunteers

The infusion of l-Deamino-8-D-Arginine Vasopressin (DDAVP) in normal individuals is followed by an increase in factor VIII/von Willebrand factor in plasma and by the appearance of larger multimers of von Willebrand factor (vWF) than those seen in the resting state. Since the larger multimers are rapidly cleared and proteolysis is known to cause disaggregation of large multimers, we evaluated the degree of vWF proteolysis after DDAVP. DDAVP was infused into eight normal adult volunteers and the relative proportions of the intact 225 kDa subunit and the 189, 176 and 140 kDa fragments were compared before and at different times after DDAVP infusion. The relative proportion of the 176 kDa fragment was increased while that of the other species was decreased, indicating that proteolytic fragmentation had occurred. However, plasmin did not appear to be responsible because the vWF fragments characteristically produced by this enzyme could not be detected. Concomitant analysis of vWF multimeric structure showed that these changes were accompanied by an increase in the relative proportion of the satellite bands suggesting that they were ptoteolytically generated. Proteolysis may explain, at least in part, rapid clearance of larger vWF multimers released by DDAVP.

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ABNORMAL STRUCTURE OF VON WILLEBRAND FACTOR IN MYELOPROLIFERATIVE SYNDROME IS ASSOCIATED WITH EITHER THROMBOTIC OR BLEEDING DIATHESIS

10.1055/s-0038-1644089 ◽

1987 ◽

Author(s):

M F López-Fernández ◽

C López-Berges ◽

R Martín ◽

A Pardo ◽

F J Romos ◽

...

Keyword(s):

Von Willebrand Factor ◽

Proteinase Inhibitors ◽

Relative Proportion ◽

Variable Degree ◽

Myeloproliferative Syndrome ◽

Normal Individuals ◽

Von Willebrand ◽

Willebrand Factor

The multimeric and subunit patterns of plasma von Willebrand factor (vWF) were analyzed in eight patients with myeloproliferative syndrome (MS) in order to investigate the possible existence of heterogeneity in the "in vivo" proteolytic cleavage of the protein, previously observed in this entity. Six patients lacked large vWF multimers, five of them having normal bleeding times (BT) and clinically documented episodes of thrombotic origin, whereas one patient had long BT and bleeding symptoms. Seven patients showed an increase 176 kDa subunit fragment while the 189 kDa polypeptide was increased in only one. In addition, another patient (and prior to any therapy) showed the presence of a new fragment of aproximately 95 kDa which disappeared after Busulfan therapy. The collection of blood from these patients with proteinase inhibitors did not correct the abnormalities.The infusion of DDAVP to two patients with abnormal vWF was accompanied by: the appearence of larger vWF multimers which disappeared rapidly from plasma; an increase in the relative proportion of the satellite bands of each multimer and a further increase in the 176 kDa fragment. These data show some heterogeneity in the vWF abnormality present in MS which may be related in part to a variable degree of proteolysis of vWF ocurring "in vivo" rather than "in vitro", and which may be associated to either a bleeding or (even) a thrombotic diathesis. They also suggest that despite the presence of abnormal, already proteolyzed vWF, DDAVP-enhanced proteolysis occurs in MS to a similar extent as described in normal individuals.

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Ddavp-Induced Alterations In The Multimeric Composition Of Factor Viii/Von Willebrand Factor In Normal And Von Willebrand’S Disease Plasma

10.1055/s-0038-1652462 ◽

1981 ◽

Author(s):

Z M Ruggeri ◽

R Lombardi ◽

P M Mannucci ◽

T S Zimmerman

Keyword(s):

Plasma Concentration ◽

Von Willebrand Factor ◽

Resting State ◽

Type I ◽

Normal Complement ◽

Normal Individuals ◽

Von Willebrand ◽

Willebrand Factor ◽

Insight Into ◽

Rapid Correction

DDAVP is known to induce increases in plasma FVIII/von Willebrand Factor (FVIII/vWF) concentration by release of tissue stores. We have now found that the multimeric composition of plasma FVIII/vWF alters following DDAVP administration to resemble that seen in platelets. Multimers were resolved by thin-layer SDS-agarose and SDS-agarose acrylamide electrophoresis and were identified by reaction of the fixed gels with 125I-laben ej antibody followed by autoradiography. Fifteen minutes after DDAVP infusion, larger multimers appeared in normal plasma than were present during the resting state. These larger multimers were also present in resting normal platelets, suggesting that DDAVP causes their release from tissue stores. In Type I von Willebrand s disease (vWd), there is a decreased quantity of circulating FVIII/vWF but the multi meric composition is normal in plasma and platelets. The response to DDAVP was qualitatively similar to that in normal individuals. In Type IIA vWd large multimers are absent both from plasma and platelets. Even though DDAVP induced a threefold rise in FVIII/vWF plasma concentration, these large forms did not appear. In 11B vWd only intermediate and small multimers are present in plasma but there is a normal complement of multimers in platelets. Following DDAVP there was a rapid correction of the plasma multimeric composition so that it was identical with the pattern seen in normals after DDAVP. However, this correction was transitory and the abnormal basal pattern soon reappeared. These disparate changes in plasma FVIII/vWF multimeric composition following DDAVP suggest that platelet FVIII/vWF is representative of releasable tissue stores. They also provide insight into the variable hemostatic response to this agent and suggest different pathogenic mechanisms for the vWa subtypes.

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Abnormal Structure of von Willebrand Factor in Myeloproliferative Syndrome Is Associated to Either Thrombotic or Bleeding Diathesis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645964 ◽

1987 ◽

Vol 58 (02) ◽

pp. 753-757 ◽

Cited By ~ 33

Author(s):

M F López-Fernández ◽

C López-Berges ◽

R Martín ◽

A Pardo ◽

F J Ramos ◽

...

Keyword(s):

Von Willebrand Factor ◽

Proteinase Inhibitors ◽

Relative Proportion ◽

Variable Degree ◽

Bleeding Diathesis ◽

Myeloproliferative Syndrome ◽

Von Willebrand ◽

Willebrand Factor

SummaryThe multimeric and subunit patterns of plasma von Willebrand factor (vWF) were analyzed in eight patients with myeloproliferative syndrome (MS) in order to investigate the possible existence of heterogeneity in the “in vivo” proteolytic cleavage of the protein, previously observed in this entity. Six patients lacked large vWF multimers, five of them having normal bleeding times (BT) and clinically documented episodes of thrombotic origin, whereas one patient had long BT and bleeding symptoms. Seven patients showed a relative increase in the 176 kDa subunit fragment while the 189 kDa polypeptide was increased in only one. In addition, another patient (and prior to any therapy) showed the presence of a new fragment of approximately 95 kDa which disappeared after Busulfan therapy. The collection of blood from these patients with proteinase inhibitors did not correct the abnormalities.The infusion of DDAVP to two patients with abnormal vWF was accompanied by: the appearance of larger vWF multimers which disappeared rapidly from plasma; an increase in the relative proportion of the satellite bands of each multimer and a further increase of the 176 kDa fragment. These data point to some heterogeneity in the vWF abnormality present in MS which may be related in part to a variable degree of proteolysis of vWF occurring “in vivo” rather than “in vitro”, and which may be associated to either a thrombotic or a bleeding diathesis. They also suggest that despite the presence of abnormal, already proteolyzed vWF, DDAVP-enhanced proteolysis occurs in MS to a similar extent to what is described in normal individuals.

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The Interaction of Botrocetin with Normal or Variant von Willebrand Factor (Types IIA and IIB) and Its Inhibition by Monoclonal Antibodies that Block Receptor Binding

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646298 ◽

1992 ◽

Vol 68 (04) ◽

pp. 464-469 ◽

Cited By ~ 9

Author(s):

Y Fujimura ◽

S Miyata ◽

S Nishida ◽

S Miura ◽

M Kaneda ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Von Willebrand Factor ◽

Binding Activity ◽

Von Willebrand Disease ◽

Platelet Glycoprotein ◽

Normal Individuals ◽

Rag 1 ◽

The One ◽

Von Willebrand ◽

Willebrand Factor

SummaryWe have recently shown the existence of two distinct forms of botrocetin (one-chain and two-chain), and demonstrated that the two-chain species is approximately 30 times more active than the one-chain in promoting von Willebrand factor (vWF) binding to platelet glycoprotein (GP) Ib. The N-terminal sequence of two-chain botrocetin is highly homologous to sea-urchin Echinoidin and other Ca2+-dependent lectins (Fujimura et al., Biochemistry 1991; 30: 1957–64).Present data indicate that purified two-chain botrocetin binds to vWF from plasmas of patients with type IIA or IIB von Willebrand disease and its interaction is indistinguishable from that with vWF from normal individuals. However, an “activated complex” formed between botrocetin and IIB vWF expresses an enhanced biological activity for binding to GP Ib whereas the complex with IIA vWF has a decreased binding activity. Among several anti-vWF monoclonal antibodies (MoAbs) which inhibit ristocetin-induced platelet aggregation and/or vWF binding to GPIb, only two MoAbs (NMC-4 and RFF-VIII RAG:1) abolished direct binding between purified botrocetin and vWF. This suggests that they recognize an epitope(s) on the vWF molecule in close proximity to the botrocetin binding site.

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Further specificity characterization of von Willebrand factor inhibitors developed in two patients with severe von Willebrand disease

Blood ◽

10.1182/blood.v72.1.116.116 ◽

1988 ◽

Vol 72 (1) ◽

pp. 116-120 ◽

Cited By ~ 3

Author(s):

MF Lopez-Fernandez ◽

R Martin ◽

C Lopez-Berges ◽

F Ramos ◽

N Bosch ◽

...

Keyword(s):

Von Willebrand Factor ◽

Complex Structure ◽

Relative Proportion ◽

Von Willebrand Disease ◽

Rabbit Antibody ◽

Human Factor Viii ◽

Rabbit Polyclonal Antibody ◽

Von Willebrand ◽

Willebrand Factor

Abstract Circulating inhibitors against von Willebrand factor (vWF) that show the properties of heterologous IgG antibodies have been described in a few patients with severe von Willebrand disease (vWD). The present study provides further characterization of inhibitors from two patients with severe vWD. Inhibitors in both, like polyclonal rabbit antibody, detected all sizes of multimers and the complex structure of each multimer from platelets and plasma of normal individuals as well as from plasma of patients with IIA, IIB, and IIC vWD. Both inhibitors and the rabbit antibody reacted mainly with the intact 225-Kd vWF subunit and the 189-H and 140-Kd fragments in contrast to monoclonal antibodies specific for vWF fragments that detected a higher relative proportion of 176-Kd fragment. Furthermore, all these antibodies recognized fragment III, although one inhibitor and rabbit polyclonal antibody reacted poorly and the other inhibitor did not react at all with reduced fragment II of vWF digested with Staphylococcus aureus V-8 protease. These data suggest that although human inhibitors from severe vWD patients may behave, to some extent, as polyclonal heterologous antibodies against native vWF, the former show striking differences in their target specificity as well as a much broader specificity than that described for human factor VIII inhibitors.

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Successful management of multiple pregnancies in a family with varying severity of Von Willebrand disease

Obstetric Medicine ◽

10.1177/1753495x17754150 ◽

2018 ◽

Vol 11 (4) ◽

pp. 192-194

Author(s):

Patrick Harrington ◽

Pippa Kyle ◽

Jacky Cutler ◽

Bella Madan

Keyword(s):

Von Willebrand Factor ◽

Von Willebrand Disease ◽

The Other ◽

Severe Phenotype ◽

Mild Phenotype ◽

History Of ◽

Specialist Treatment ◽

Factor Concentrate ◽

Von Willebrand ◽

Willebrand Factor

We present the obstetric history of a family of three sisters with Von Willebrand disease, managed in our centre over the course of nine successful pregnancies. The abnormalities result from inheritance of an exon 50 skipping mutation in the Von Willebrand factor gene, resulting from consanguinity. Two of the sisters were identified as having a severe phenotype with a Von Willebrand factor level of less than 5 IU/dl, with the other having a mild phenotype. Of the sisters with a severe phenotype, one had a number of prenatal complications and required early onset prophylaxis with Von Willebrand factor concentrate, whilst the other had a less complicated clinical course, only requiring Von Willebrand factor concentrate to cover labour. The sister with mild Von Willebrand disease had a rise in Von Willebrand factor levels during pregnancy and required no specialist treatment. The report highlights the markedly different clinical courses that can occur in patients with Von Willebrand disease and the different approaches to management.

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TWO-DIMENSIONAL MULTIMERIC ANALYSIS OF PLASMA AND PLATELET VON WILLEBRAND FACTOR (VWF) WITH IDENTIFICATION OF PLATELET VWF FRAGMENTS EXPRESSING A NEO-ANTIGEN

10.1055/s-0038-1642872 ◽

1987 ◽

Author(s):

J Dent ◽

J Roberts ◽

Z M Ruggeri ◽

T S Zimmerman

Keyword(s):

Monoclonal Antibody ◽

Von Willebrand Factor ◽

Polyacrylamide Gel Electrophoresis ◽

Von Willebrand Disease ◽

Proteolytic Degradation ◽

Normal Platelet ◽

Protease Digestion ◽

Agarose Electrophoresis ◽

Von Willebrand ◽

Willebrand Factor

SDS-agarose electrophoresis of von Willebrand factor (vWF) was followed by reduction, second dimension SDS-polyacrylamide gel electrophoresis and immunoblotting with monoclonal anti-vWF antibodies. The multiple bands in each multimer of plasma vWF from normal and IIA von Willebrand disease (vWD) patients were shown to contain varying proportions of the intact 225 kDa vWF subunit and fragments of 189, 176, and 140 kDa. Only one relatively minor band in each multimer was composed entirely of the intact 225 kDa subunit. Repeating bands in successively larger multimers up to the thirteenth, exhibited similar compositions, whereas the largest multimers contained only the intact 225 kDa subunit. Thus the complex multimeric pattern of plasma vWF is the result, at least in part, of proteolytic degradation, and smaller multimers may derive from proteolytic degradation of larger species. In contrast, none of the fragments present in plasma vWF were seen in the vWF derived from platelets. Rather, fragments of 172 and 182 kDa were present in the smallest one or two multimers, whereas the larger multimers contained only the intact subunit. The fragments of platelet vWF reacted only with one monoclonal antibody (K14) of the 80 tested. This antibody did not react with unreduced plasma vWF nor with the unreduced fragments generated by Staphylococcus aureus V8 protease digestion of plasma vWF and reacted very poorly with reduced intact vWF subunit. Thus, the monoclonal antibody K14 recognized a neo-antigenic epitope expressed on at least two fragments of normal platelet, but not plasma, vWF.

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