scholarly journals Characterization of the defect of the factor VIII/von Willebrand factor protein in von Willebrand's disease

Blood ◽  
1982 ◽  
Vol 59 (3) ◽  
pp. 542-548 ◽  
Author(s):  
HR Gralnick ◽  
MC Cregger ◽  
SB Williams

Abstract The factor VIII/von Willebrand factor (f.VIII/vWf) protein was purified from the plasma of a patient with von Willebrand's disease (vWd). The patient had all of the classic laboratory findings of vWd except for the ristocetin-induced platelet aggregation of his own platelet-rich plasma. The disease has been documented in three generations. Comparison of the purified normal and vWd f.VIIi/vWf protein revealed several abnormalities, including decreased concentration of f.VIII/vWf antigen; decreased specific vWf activity; absence of the larger molecular forms of the f.VIII/vWf protein; carbohydrate deficiencies affecting the sialic acid, penultimate galactose and N- acetylglucosamine moieties; and decreased binding of the f.VIII/vWf protein to its platelet receptor. These studies indicate the multiplicity of biochemical and functional abnormalities associated with the f.VIII/vWf protein in vWd. f.VIII/vWf protein to normal f.VIII/vWf protein that had been treated with 2-mercaptoethanol (2-ME) to reduce the multimer size and then treated with specific exoglycosidases to remove the sialic acid and penultimate galactose residues revealed similar biologic properties.

Blood ◽  
1982 ◽  
Vol 59 (3) ◽  
pp. 542-548 ◽  
Author(s):  
HR Gralnick ◽  
MC Cregger ◽  
SB Williams

The factor VIII/von Willebrand factor (f.VIII/vWf) protein was purified from the plasma of a patient with von Willebrand's disease (vWd). The patient had all of the classic laboratory findings of vWd except for the ristocetin-induced platelet aggregation of his own platelet-rich plasma. The disease has been documented in three generations. Comparison of the purified normal and vWd f.VIIi/vWf protein revealed several abnormalities, including decreased concentration of f.VIII/vWf antigen; decreased specific vWf activity; absence of the larger molecular forms of the f.VIII/vWf protein; carbohydrate deficiencies affecting the sialic acid, penultimate galactose and N- acetylglucosamine moieties; and decreased binding of the f.VIII/vWf protein to its platelet receptor. These studies indicate the multiplicity of biochemical and functional abnormalities associated with the f.VIII/vWf protein in vWd. f.VIII/vWf protein to normal f.VIII/vWf protein that had been treated with 2-mercaptoethanol (2-ME) to reduce the multimer size and then treated with specific exoglycosidases to remove the sialic acid and penultimate galactose residues revealed similar biologic properties.


1985 ◽  
Vol 54 (02) ◽  
pp. 463-465 ◽  
Author(s):  
M Furlan ◽  
B A Perret ◽  
E A Beck

SummaryTwo recently developed tests for measurement of factor VIII/von Willebrand factor (FVIII/vWF), i.e. platetelet agglutination by botrocetin and a kinetic latex antigen assay, were compared with ristocetin cofactor and electroimmunoassay, in respect with FVIII/vWF size-distribution. FVIII/vWF was measured in six cases of atypical von Willebrand’s disease (type II), in gel-filtered fractions of normal cryoprecipitate and in the course of depolymerization of purified normal FVIII/vWF by disulfide reduction. Small molecular forms of FVIII/vWF from normal and variant type II plasma, and those derived by disulfide reduction of high-molecular weight FVIII/vWF, showed remarkably decreased reactivity in ristocetin-, botrocetin- and latex-assay. We conclude that for botrocetin-induced platelet agglutination, as well as for agglutination of antibody-coated latex particles, multiple interactions with repeating subunits of FVIII/vWF are required. As a practical consequence, the combined measurement of FVIII/vWF by the latex test and electroimmunoassay provides a simple tool for discriminating between the classical von Willebrand’s disease and its variants.


Blood ◽  
1986 ◽  
Vol 68 (3) ◽  
pp. 668-672 ◽  
Author(s):  
L Holmberg ◽  
E Berntorp ◽  
M Donner ◽  
IM Nilsson

Abstract In eight members of one family, platelets in platelet-rich plasma aggregated at much lower ristocetin concentrations than normal. Ivy bleeding time was variously prolonged, and von Willebrand factor antigen (vWF:Ag), ristocetin cofactor activity, and factor VIII coagulant activity were decreased. Most of the affected members had had slight to rather severe bleeding symptoms. Platelet-type von Willebrand's disease (vWD) could be ruled out. All multimers of vWF:Ag were found in plasma as well as platelets. Administration of 1-desamino- 8-D-arginine vasopressin (DDAVP) to the propositus did not cause thrombocytopenia, and platelet-poor plasma obtained immediately after did not aggregate normal platelets. The molecular defect in this family, inherited as an autosomal dominant, resembles the one in type IIB because of the response to ristocetin but differs from IIB because all vWF:Ag multimers are present in plasma and the response to DDAVP is atypical. We conclude that this family has a new subtype of vWD and propose that structural as well as functional criteria should be used for a proper classification of vWD.


Blood ◽  
1986 ◽  
Vol 67 (2) ◽  
pp. 465-468 ◽  
Author(s):  
HR Gralnick ◽  
SB Williams ◽  
LP McKeown ◽  
ME Rick ◽  
P Maisonneuve ◽  
...  

Abstract 1-D-Amino(8-D-arginine)-vasopressin (DDAVP) infusion in three patients with type IIa von Willebrand's disease (vWD) resulted in a normalization of the factor VIII coagulant, factor VIII-related antigen, and von Willebrand factor (vWF) (ristocetin cofactor) activities and the bleeding time. The normalization of these hemostatic parameters persisted for four hours. Over the same time period there was a marked increase in the quantity of the vWF multimers when blood was collected in the presence of protease inhibitors. The vWF multimers present were even larger than the normal. When blood was collected in the absence of protease inhibitors, a smaller increase in the plasma vWF multimers was observed and fewer of the intermediate and larger vWF multimers were seen; multimers larger than those present in normal plasma were not visualized. The platelet vWF multimers and activities did not change with or without inhibitors. These studies suggest that there is a subgroup of patients with type IIa vWD who respond to DDAVP with complete normalization of their hemostatic abnormalities and whose vWF is sensitive to proteolysis.


Blood ◽  
1982 ◽  
Vol 59 (6) ◽  
pp. 1272-1278 ◽  
Author(s):  
ZM Ruggeri ◽  
PM Mannucci ◽  
R Lombardi ◽  
AB Federici ◽  
TS Zimmerman

Abstract We have studied the modifications in the multimeric composition of plasma factor VIII/von Willebrand factor and the bleeding time response following administration of 1-Deamino-[8-D-arginine]-Vasopressin (DDAVP) to patients with different subtypes of von Willebrand's disease. In type I, all multimers were present in plasma in the resting state, though they were decreased in concentration. Administration of DDAVP resulted in an increased concentration of these forms as well as the appearance of larger forms than were previously present. There was concomitant correction of the bleeding time. In type IIA, large multimers were absent in the resting state, and although DDAVP induced an average threefold increase in the plasma concentration of factor VIII/von Willebrand factor, the larger multimers did not appear and the bleeding time, although shortened, was not corrected. In contrast, the larger multimers that were also absent from type IIB plasma in the resting state rapidly appeared following DDAVP administration. However, their appearance was transitory and the bleeding time, as in IIA patients, was shortened but not corrected. The characteristic multimeric composition of platelet factor VIII/von Willebrand factor in given subtypes predicted the alteration in plasma factor VIII/von Willebrand factor induced by DDAVP. These studies provide evidence that the different subtypes of von Willebrand's disease represent distinct abnormalities of factor VIII/von Willebrand factor. They also suggest that complete hemostatic correction following DDAVP can be routinely expected only in type I von Willebrand's disease, and only if factor VIII/von Willebrand factor can be raised to normal levels.


Blood ◽  
1981 ◽  
Vol 57 (6) ◽  
pp. 1140-1143 ◽  
Author(s):  
ZM Ruggeri ◽  
TS Zimmerman

We have analyzed the multimeric structure of factor VIII/von Willebrand factor in plasma by sodium dodecyl sulfate electrophoresis using gels of varying porosity and a discontinuous buffer system. Factor VIII/von Willebrand factor bands were identified by reaction with 125I-labeled affinity-purified antibody and subsequent autoradiography. In 1% agarose gels, normal plasma displayed a series of sharply defined oligomers. However, increasing the agarose concentration to 2.0% or utilizing mixtures of 0.8% agarose--1.75% acrylamide revealed two bands of lesser intensity interposed between the major bands. When the acrylamide concentration in the gels was increased to 2.5%, bands with a faster mobility than IgM and fibronectin were now evident. Type IIA von Willebrand's disease showed not only an absence of the larger multimers but also a relative increase in several of the newly identified bands as compared to type IIB, type I, and normal. These studies suggest that factor VII/von Willebrand factor in IIA von Willebrand's disease is structurally different from that in other forms of the disorder. They also indicate that the multimeric composition of factor VII/von Willebrand factor is more complex than can be explained by simple linear polymerization of a single protomer.


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