scholarly journals Type 2M:Milwaukee-1 von Willebrand disease: an in-frame deletion in the Cys509-Cys695 loop of the von Willebrand factor A1 domain causes deficient binding of von Willebrand factor to platelets

Blood ◽  
1996 ◽  
Vol 88 (7) ◽  
pp. 2559-2568 ◽  
Author(s):  
DJ Mancuso ◽  
PA Kroner ◽  
PA Christopherson ◽  
EA Vokac ◽  
JC Gill ◽  
...  

This report examines the genetic basis of a variant form of moderately severe von Willebrand disease (vWD) characterized by low plasma von Willebrand factor antigen (vWF:Ag) levels and normal multimerization, typical of type 1 vWD, but disproportionately-low agonist-mediated platelet-binding activity. We identified an in-frame deletion in vWF exon 28 in three generations of affected family members, who are heterozygous for this mutation. The deletion of nucleotides 4,173–4,205 results in the loss of amino acids Arg629-Gln639 in the Cys509-Cys695 loop of the A1 domain in mature vWF. The secreted mutant vWF showed a normal multimeric profile but did not bind to platelets in the presence of optimal concentrations of either ristocetin or botrocetin. The mutant vWF also failed to interact with heparin, and with vWF monoclonal antibody AvW3, which blocks the binding of vWF to GPlb. In addition, mutant vWF showed reduced secretion from transfected cells concomitant with increased intracellular levels. These results confirm that the deletion is the genetic defect responsible for the reduced interaction of vWF with platelets. We have designated this new variant type 2M:Milwaukee-1 vWD. Our analysis suggests that the potential frequency of this phenotype in individuals diagnosed with type 1 vWD is about 0.5%.

2019 ◽  
Vol 25 ◽  
pp. 107602961986691
Author(s):  
Chatphatai Moonla ◽  
Benjaporn Akkawat ◽  
Yaowaree Kittikalayawong ◽  
Autcharaporn Sukperm ◽  
Mukmanee Meesanun ◽  
...  

Correlations between bleeding symptoms and von Willebrand factor (VWF) levels may help to predict hemorrhagic severity in the Westerners with von Willebrand disease (VWD), but data in Asians are lacking. In this study, Thai patients with VWF levels <50 IU/dL without any secondary causes were enrolled from 1988 to 2018 to determine the relationship between VWF levels and hemorrhagic manifestations. According to the current concept, we reclassified VWD and low VWF by VWF levels ≤30 and 30 to 50 IU/dL, respectively. Type 2 VWD was diagnosed if VWF activity to antigen ratio was ≤0.6. Bleeding severity was determined by the condensed MCMDM-1VWD bleeding score (BS). Among 83 patients, VWF activities showed negative correlations with BS ( P = .001), which were higher in type 2 (median: 7, interquartile range [IQR]: 5-11) compared with type 1 VWD (median: 3, IQR: 2-4) and low VWF (median: 4, IQR: 2-8). Bleeding symptoms were indistinguishable between type 1 VWD and low VWF using the 30 IU/dL cutoff point. However, VWF ristocetin cofactor activity or gain-of-function mutant glycoprotein Ib binding activity <36.5 IU/dL and VWF collagen binding activity <34.5 IU/dL could predict increased bleeding risk (BS ≥3) by 92.3% specificity and 70.0% sensitivity ( P < .0001).


Blood ◽  
2006 ◽  
Vol 108 (10) ◽  
pp. 3344-3351 ◽  
Author(s):  
Sandra L. Haberichter ◽  
Michael Balistreri ◽  
Pamela Christopherson ◽  
Patricia Morateck ◽  
Stefana Gavazova ◽  
...  

Abstract Type 1 von Willebrand disease (VWD) is characterized by a partial quantitative deficiency of von Willebrand factor (VWF). Few VWF gene mutations have been identified that cause dominant type 1 VWD. The decreased survival of VWF in plasma has recently been identified as a novel mechanism for type 1 VWD. We report 4 families with moderately severe type 1 VWD characterized by low plasma VWF:Ag and FVIII:C levels, proportionately low VWF:RCo, and dominant inheritance. A decreased survival of VWF in affected individuals was identified with VWF half-lives of 1 to 3 hours, whereas the half-life of VWF propeptide (VWFpp) was normal. DNA sequencing revealed a single (heterozygous) VWF mutation in affected individuals, S2179F in 2 families, and W1144G in 2 families, neither of which has been previously reported. We show that the ratio of steady-state plasma VWFpp to VWF:Ag can be used to identify patients with a shortened VWF half-life. An increased ratio distinguished affected from unaffected individuals in all families. A significantly increased VWFpp/VWF:Ag ratio together with reduced VWF:Ag may indicate the presence of a true genetic defect and decreased VWF survival phenotype. This phenotype may require an altered clinical therapeutic approach, and we propose to refer to this phenotype as type-1C VWD.


Blood ◽  
2003 ◽  
Vol 101 (3) ◽  
pp. 946-948 ◽  
Author(s):  
Rosemarie A. Reiter ◽  
Paul Knöbl ◽  
Katalin Varadi ◽  
Peter L. Turecek

Abstract von Willebrand factor–cleaving protease (ADAMTS13) cleaves von Willebrand factor (VWF) and regulates its physiologic function. To investigate the relation between ADAMTS13 activity and VWF, we compared ADAMTS13 activity with the VWF-related parameters VWF antigen (VWF:Ag), VWF collagen-binding activity (VWF:CBA), VWF-propeptide, proVWF, and VWF multimeric composition in 10 healthy volunteers and 3 patients with type 1 von Willebrand disease before and after infusing 0.3 μg/kg desmopressin. The VWF-related parameters in the volunteers increased 60 minutes after start of infusion by 3.7-fold for VWF:Ag, 7.2-fold for propeptide, and 2.2-fold for VWF:CBA. Unusually large VWF multimers and traces of proVWF appeared. The ADAMTS13 activity decreased to about half the initial value. After 24 hours values returned to baseline. Patients with type 1 von Willebrand disease showed similar results. We conclude that the inverse correlation between ADAMTS13 and VWF-related parameters suggests a consumption of ADAMTS13 after the desmopressin-induced release of higher multimers of VWF.


1992 ◽  
Vol 68 (04) ◽  
pp. 464-469 ◽  
Author(s):  
Y Fujimura ◽  
S Miyata ◽  
S Nishida ◽  
S Miura ◽  
M Kaneda ◽  
...  

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.


1993 ◽  
Vol 69 (02) ◽  
pp. 173-176 ◽  
Author(s):  
Anna M Randi ◽  
Elisabetta Sacchi ◽  
Gian Carlo Castaman ◽  
Francesco Rodeghiero ◽  
Pier Mannuccio Mannucci

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.


2020 ◽  
Vol 432 (2) ◽  
pp. 305-323 ◽  
Author(s):  
Alexander Tischer ◽  
Maria A. Brehm ◽  
Venkata R. Machha ◽  
Laurie Moon-Tasson ◽  
Linda M. Benson ◽  
...  

2021 ◽  
Vol 47 (02) ◽  
pp. 192-200
Author(s):  
James S. O'Donnell

AbstractThe biological mechanisms involved in the pathogenesis of type 2 and type 3 von Willebrand disease (VWD) have been studied extensively. In contrast, although accounting for the majority of VWD cases, the pathobiology underlying partial quantitative VWD has remained somewhat elusive. However, important insights have been attained following several recent cohort studies that have investigated mechanisms in patients with type 1 VWD and low von Willebrand factor (VWF), respectively. These studies have demonstrated that reduced plasma VWF levels may result from either (1) decreased VWF biosynthesis and/or secretion in endothelial cells and (2) pathological increased VWF clearance. In addition, it has become clear that some patients with only mild to moderate reductions in plasma VWF levels in the 30 to 50 IU/dL range may have significant bleeding phenotypes. Importantly in these low VWF patients, bleeding risk fails to correlate with plasma VWF levels and inheritance is typically independent of the VWF gene. Although plasma VWF levels may increase to > 50 IU/dL with progressive aging or pregnancy in these subjects, emerging data suggest that this apparent normalization in VWF levels does not necessarily equate to a complete correction in bleeding phenotype in patients with partial quantitative VWD. In this review, these recent advances in our understanding of quantitative VWD pathogenesis are discussed. Furthermore, the translational implications of these emerging findings are considered, particularly with respect to designing personalized treatment plans for VWD patients undergoing elective procedures.


Blood ◽  
1994 ◽  
Vol 84 (10) ◽  
pp. 3378-3384 ◽  
Author(s):  
PJ van Genderen ◽  
T Vink ◽  
JJ Michiels ◽  
MB van 't Veer ◽  
JJ Sixma ◽  
...  

Abstract An 82-year-old man with a low-grade malignant non-Hodgkin lymphoma and an IgG3 lambda monoclonal gammopathy presented a recently acquired bleeding tendency, characterized by recurrent epistaxis, easy bruising, and episodes of melena, requiring packed red blood cell transfusions. Coagulation studies showed a von Willebrand factor (vWF) defect (Ivy bleeding time, > 15 minutes; vWF antigen [vWF:Ag], 0.08 U/mL; ristocetin cofactor activity [vWF:RCoF], < 0.05 U/mL; collagen binding activity [vWF:CBA], 0.01 U/mL; absence of the high molecular weight multimers of vWF on multimeric analysis). Mixing experiments suggested the presence of an inhibitor directed against the vWF:CBA activity of vWF without significantly inhibiting the FVIII:C, vWF:Ag, and vWF:RCoF activities. The inhibitor was identified as an antibody of the IgM class by immunoabsorption of vWF and inhibitor-vWF complexes from the plasma of the patient. Subsequent immunoprecipitation experiments using recombinant fragments of vWF showed that the inhibitor reacted with both the glycoprotein Ib binding domain (amino acids [aa] 422–826) and the A3 (aa 909–1112) domain of vWF, but not with the A2 (aa 716–908) or D4 (aa 1183–1535) domains. We conclude that the IgM autoantibody inhibits the vWF:CBA activity by reacting with an epitope present on both the glycoprotein Ib and A3 domains of vWF.


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