scholarly journals Heterogeneity of type I von Willebrand disease: evidence for a subgroup with an abnormal von Willebrand factor

Blood ◽  
1985 ◽  
Vol 66 (4) ◽  
pp. 796-802 ◽  
Author(s):  
PM Mannucci ◽  
R Lombardi ◽  
R Bader ◽  
L Vianello ◽  
AB Federici ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Plasma Concentrations ◽  
Sodium Dodecyl ◽  
Von Willebrand Disease ◽  
Type I ◽  
Normal Platelet ◽  
Complete Set ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Factor Antigen

Type I von Willebrand disease (vWD) is characterized by equally low plasma concentrations of von Willebrand factor antigen (vWF:Ag) and ristocetin cofactor (RiCof) and by the presence of all vWF multimers in sodium dodecyl sulfate (SDS)-agarose gel electrophoresis. For 17 patients (13 kindreds) diagnosed with these criteria, we have studied the platelet contents of vWF:Ag and RiCof and the changes of these in plasma after DDAVP infusion. Platelet vWF:Ag and RiCof were normal in four kindreds (called “platelet normal” subgroup); following 1-deamino- 8-D-arginine vasopressin; plasma vWF:Ag, RiCof and the bleeding time (BT) became normal. In six kindreds, platelet vWF:Ag and RiCof were equally low (platelet low); after DDAVP, plasma vWF:Ag and RiCof remained low, and the BT was prolonged. In three additional kindreds, platelets contained normal concentrations of vWF:Ag, but RiCof was very low (platelet discordant); even though a complete set of multimers was found in plasma and platelets, there was a relatively small amount of large multimers. After DDAVP, plasma vWF:Ag became normal, but RiCof remained low and the BT was very prolonged. These findings demonstrated that there can be an abnormal vWF (RiCof less than vWF:Ag) even in type I vWD, coexisting with a complete set of vWF multimers (platelet discordant); that the abnormal vWF can be shown more clearly in platelets than in plasma or else in plasma after DDAVP infusion; and that DDAVP normalizes the BT only in those patients with normal platelet levels of both vWF:Ag and RiCof (platelet normal).

scholarly journals Heterogeneity of type I von Willebrand disease: evidence for a subgroup with an abnormal von Willebrand factor

Blood ◽  
1985 ◽  
Vol 66 (4) ◽  
pp. 796-802 ◽  
Author(s):  
PM Mannucci ◽  
R Lombardi ◽  
R Bader ◽  
L Vianello ◽  
AB Federici ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Plasma Concentrations ◽  
Sodium Dodecyl ◽  
Von Willebrand Disease ◽  
Type I ◽  
Normal Platelet ◽  
Complete Set ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Factor Antigen

Abstract Type I von Willebrand disease (vWD) is characterized by equally low plasma concentrations of von Willebrand factor antigen (vWF:Ag) and ristocetin cofactor (RiCof) and by the presence of all vWF multimers in sodium dodecyl sulfate (SDS)-agarose gel electrophoresis. For 17 patients (13 kindreds) diagnosed with these criteria, we have studied the platelet contents of vWF:Ag and RiCof and the changes of these in plasma after DDAVP infusion. Platelet vWF:Ag and RiCof were normal in four kindreds (called “platelet normal” subgroup); following 1-deamino- 8-D-arginine vasopressin; plasma vWF:Ag, RiCof and the bleeding time (BT) became normal. In six kindreds, platelet vWF:Ag and RiCof were equally low (platelet low); after DDAVP, plasma vWF:Ag and RiCof remained low, and the BT was prolonged. In three additional kindreds, platelets contained normal concentrations of vWF:Ag, but RiCof was very low (platelet discordant); even though a complete set of multimers was found in plasma and platelets, there was a relatively small amount of large multimers. After DDAVP, plasma vWF:Ag became normal, but RiCof remained low and the BT was very prolonged. These findings demonstrated that there can be an abnormal vWF (RiCof less than vWF:Ag) even in type I vWD, coexisting with a complete set of vWF multimers (platelet discordant); that the abnormal vWF can be shown more clearly in platelets than in plasma or else in plasma after DDAVP infusion; and that DDAVP normalizes the BT only in those patients with normal platelet levels of both vWF:Ag and RiCof (platelet normal).

The Genetic Defect of Type I von Willebrand Disease “Vicenza” Is Linked to the von Willebrand Factor Gene

1993 ◽  
Vol 69 (02) ◽  
pp. 173-176 ◽  
Author(s):  
Anna M Randi ◽  
Elisabetta Sacchi ◽  
Gian Carlo Castaman ◽  
Francesco Rodeghiero ◽  
Pier Mannuccio Mannucci
Keyword(s):  
Von Willebrand Factor ◽  
Autosomal Dominant ◽  
Genetic Defect ◽  
Von Willebrand Disease ◽  
Type I ◽  
Bleeding Tendency ◽  
Factor Gene ◽  
Low Levels ◽  
Von Willebrand ◽  
Willebrand Factor

SummaryType I von Willebrand disease (vWD) Vicenza is a rare variant with autosomal dominant transmission, characterized by the presence of supranormal von Willebrand factor (vWF) multimers in plasma, similar to those normally found in endothelial cells and megakaryocytes. The patients have very low levels of plasma vWF contrasting with a mild bleeding tendency. The pathophysiology of this subtype is still unknown. The presence of supranormal multimers in the patients’ plasma could be due to a mutation in the vWF molecule which affects post-translational processing, or to a defect in the cells’ processing machinery, independent of the vWF molecule. In order to determne if type I vWD Vicenza is linked to the vWF gene, we studied six polymorphic systems identified within the vWF gene in two apparently unrelated families with type I vWD Vicenza. The results of this study indicate a linkage between vWF gene and the type I vWD Vicenza trait. This strongly suggests that type I vWD Vicenza is due to a mutation in one of the vWF alleles, which results in an abnormal vWF molecule that is processed to a lesser extent than normal vWF.

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

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.

scholarly journals Unique interactions of asialo von Willebrand factor with platelets in platelet-type von Willebrand disease

Blood ◽  
1987 ◽  
Vol 70 (6) ◽  
pp. 1804-1809 ◽  
Author(s):  
JL Miller ◽  
ZM Ruggeri ◽  
VA Lyle
Keyword(s):  
Monoclonal Antibody ◽  
Von Willebrand Factor ◽  
Specific Binding ◽  
Platelet Rich Plasma ◽  
Von Willebrand Disease ◽  
Normal Platelet ◽  
High Affinity Binding Site ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Formalin Fixed

Abstract The present studies demonstrate that platelets from patients with platelet-type von Willebrand disease show specific and saturable binding of asialo von Willebrand factor (AS-vWF) under conditions where such binding is not observed with normal platelets. Although specific binding of 125I-AS-vWF to formalin-fixed normal platelets could not be demonstrated, specific binding to fixed patient platelets was seen with an apparent Kd of 1.3 micrograms/mL and specific maximally bound ligand of 0.40 micrograms/10(8) platelets. Preincubation of patient platelets with the antiglycoprotein Ib (anti-GPIb) monoclonal antibody AS-2 reduced total binding close to the level of computer-estimated nonspecific binding. In contrast, binding was not reduced by preincubation with anti-GPIIb/IIIa monoclonal antibody or with 5 mmol/L EDTA. Under stirring conditions, the binding of AS-vWF to fixed patient platelets was accompanied by a strong agglutination response. AS-vWF- induced agglutination was similarly observed in patient but not normal platelet-rich plasma (PRP) in the presence of 5 mmol/L EDTA. In the absence of EDTA, AS-vWF produced a full aggregation response in patient PRP at concentrations as low as 0.1 microgram/mL in contrast to the 2 to 20 micrograms/mL required by normal PRP. Both thromboxane B2 formation and adenosine triphosphate secretion showed an AS-vWF concentration dependence paralleling the aggregation responses. These studies show that a major difference in the platelets from patients with platelet-type von Willebrand disease is the presence of an exposed, high-affinity binding site associated with GPIb that recognizes AS-vWF.

The role of platelet von Willebrand factor in platelet adhesion and thrombus formation: a study of 34 patients with various subtypes of type I von Willebrand disease

1994 ◽  
Vol 86 (2) ◽  
pp. 327-332 ◽  
Author(s):  
Edith Fressinaud ◽  
Augusto B. Federici ◽  
Giancarlo Castaman ◽  
Chantal Rothschild ◽  
Francesco Rodeghiero ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Platelet Adhesion ◽  
Thrombus Formation ◽  
Von Willebrand Disease ◽  
Type I ◽  
Von Willebrand ◽  
Willebrand Factor

scholarly journals Further characterization of platelet-type von Willebrand's disease in Japan

Blood ◽  
1984 ◽  
Vol 64 (6) ◽  
pp. 1254-1262 ◽  
Author(s):  
H Takahashi ◽  
M Handa ◽  
K Watanabe ◽  
Y Ando ◽  
R Nagayama ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Platelet Rich Plasma ◽  
Sodium Dodecyl ◽  
Membrane Glycoproteins ◽  
Glycoprotein Ib ◽  
Normal Platelet ◽  
Platelet Receptor ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract We studied four patients who showed aggregation of platelets in platelet-rich plasma at lower concentrations of ristocetin than those required for normal platelet-rich plasma and who demonstrated an increased capacity of the platelets to bind normal von Willebrand factor. The four patients were from two Japanese families. Platelets from one family aggregated spontaneously in vitro, and platelets from both families aggregated upon the addition of normal plasma and cryoprecipitate, in the absence of ristocetin or other agonists. Analysis of the multimeric composition of von Willebrand factor by sodium dodecyl sulfate-agarose gel electrophoresis revealed a decrease in large multimers or a decrease in both large and intermediate multimers in plasma, but normal multimers in platelets. 1-Deamino-[8-D- arginine]-vasopressin caused by an immediate appearance of larger multimers in plasma, followed by the rapid disappearance of these multimers from circulating plasma. Analysis of platelet membrane glycoproteins from the patients showed that there were two distinct bands in the glycoprotein I region; one migrated in a slower region and the other in a faster region than normal glycoprotein Ib. We suggest that the platelet receptor abnormality in these patients is related to this abnormality of glycoprotein Ib.

PRODUCTION OF ANTIBODIES TO HUMAN VON WILLEBRAND FACTOR IN LAYING HENS. ISOLATION OF IMMUNOGLOBULINS AND APPLICATIONS TO THE DETECTION OF MOLECULAR DEFECTS OF VON WILLEBRAND FACTOR

1987 ◽  
Author(s):  
F Toti ◽  
A Stierlé ◽  
M L Wiesel ◽  
A Schwartz ◽  
J M Freyssinet ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Laying Hens ◽  
Protein A ◽  
Von Willebrand Disease ◽  
Primary Hemostasis ◽  
Normal Platelet ◽  
Electrophoretic Patterns ◽  
Egg Yolks ◽  
Von Willebrand ◽  
Willebrand Factor

Von Willebrand disease (vWD) is an inherited disorder of primary hemostasis caused by deficiency or structural abnormalities of von Willebrand factor (vWF). VWF circulates in plasma and is also present in platelets. Plasma vWF, the carrier protein for factor VIII, is a large multimeric glycoprotein composed of identical subunits linked by disulfide bridges. Plasma and platelet vWF display distinct multimeric electrophoretic patterns. The different vWD subtypes can be classified either by the determination of vWFantigen (vWFíAg) and/or by multimer distribution. Antibodies to human vWF were raised in laying hens by intramuscular injections of purified human vWF. Immunoglobulins were isolated from egg yolks by selective polyethylene glycol and ammonium sulfate precipitations. These antibodies appeared to be monospecific, as they did not react with the plasma proteins of a patient with severe vWD. The pullets received weekly 50 μg vWF for 4 weeks and then had monthly injections. The antibodies occurred as early as the third injection, the yield being 300 to 500 mg of immunoglobulin per week (6-7 eggs). The titre could be constant over periods greater than 1 year. These immunoglobulins to vWF were tested in vWFíAg electroimmunoassays and for the multimer analysis of plasma and platelet vWF by electrophoresis and immunoblotting techniques. In no case could a difference be detected between assays performed with rabbit monospecific antiserum or with yolk immunoglobulins to human vWF. Ten to 12 multimers could be revealed for normal plasma vWF and up to 12 to 14 bands for normal platelet vWF (1.7% agarose). In the case of vWD, the electrophoresis patterns were identical with both antibodies. Thus, antibodies to vWF raised in laying hens are a suitable tool to detect and to characterize vWD. Although they do not interact with protein A, yolk antibodies are certainly advantageous to produce, as they do not contain IgM or IgA. Immunoglobulin fractions can contain up to 10 % of specific antibodies. Since they are available in larger quantities and are easy to isolate, larger homogeneous batches of antibodies can be obtained. This method may easily be applied to develop antibodies to a variety of antigens.

scholarly journals Platelet von Willebrand factor: an important determinant of the bleeding time in type I von Willebrand's disease

Blood ◽  
1986 ◽  
Vol 68 (1) ◽  
pp. 58-61 ◽  
Author(s):  
HR Gralnick ◽  
ME Rick ◽  
LP McKeown ◽  
SB Williams ◽  
RI Parker ◽  
...  
Keyword(s):  
Von Willebrand Factor ◽  
Bleeding Time ◽  
Time Factors ◽  
Type I ◽  
Von Willebrand's Disease ◽  
Von Willebrand’S Disease ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Factor Antigen ◽  
Ristocetin Cofactor

Abstract We studied 17 patients with moderate to mild type I von Willebrand's disease (vWd) and correlated the bleeding time with the plasma von Willebrand factor antigen (vWf Ag), the plasma vWf activity (ristocetin cofactor), the platelet vWf Ag, and the platelet vWf activity. We found an excellent correlation between the bleeding time and the platelet vWf activity and, to a lesser extent, between the bleeding time and the platelet vWf Ag. The length of the bleeding time was inversely proportional to the level of the platelet vWf (P less than .001) or, to a lesser extent, the platelet vWf Ag (P less than .05). The plasma vWf Ag and activity did not correlate significantly with the bleeding time. These studies indicate that the platelet vWf is one of the important bleeding time factors in type I vWd and that the platelet vWf plays an important role in the early steps of hemostasis.

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