scholarly journals The disulfide bond Cys2724-Cys2774 in the C-terminal cystine knot domain of von Willebrand factor is critical for its dimerization and secretion

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Yuxin Zhang ◽  
Fengwu Chen ◽  
Aizhen Yang ◽  
Xiaoying Wang ◽  
Yue Han ◽  
...  

Abstract Background Type 3 von Willebrand disease (VWD) exhibits severe hemorrhagic tendency with complicated pathogenesis. The C-terminal cystine knot (CTCK) domain plays an important role in the dimerization and secretion of von Willebrand factor (VWF). The CTCK domain has four intrachain disulfide bonds including Cys2724-Cys2774, Cys2739-Cys2788, Cys2750-Cys2804 and Cys2754-Cys2806, and the single cysteine mutation in Cys2739-Cys2788, Cys2750-Cys2804 and Cys2754-Cys2806 result in type 3 VWD, demonstrating the crucial role of these three disulfide bonds in VWF biosynthesis, however, the role of the remaining disulfide bond Cys2724-Cys2774 remains unclear. Method and results In this study, by the next-generation sequencing we found a missense mutation a c.8171G>A (C2724Y) in the CTCK domain of VWF allele in a patient family with type 3 VWD. In vitro, VWF C2724Y protein was expressed normally in HEK-293T cells but did not form a dimer or secrete into cell culture medium, suggesting that C2724 is critical for the VWF dimerization, and thus for VWF multimerization and secretion. Conclusions Our findings provide the first genetic evidence for the important role of Cys2724-Cys2774 in VWF biosynthesis and secretion. Therefore, all of the four intrachain disulfide bonds in CTCK monomer contribute to VWF dimerization and secretion.

2006 ◽  
Vol 96 (12) ◽  
pp. 717-724 ◽  
Author(s):  
Pernilla Tjernberg ◽  
Hans Vos ◽  
Caroline Spaargaren-van Riel ◽  
Brenda Luken ◽  
Jan Voorberg ◽  
...  

SummaryVon Willebrand factor (VWF) contains a large number of cysteine residues, which all form disulfide bonds. Mutations of cysteines located in the cystine-knot (CK) domain of VWF have been identified in both qualitative type 2A (IID) and quantitative type 3 vonWillebrand disease (VWD).Our objective was to test the hypothesis that the difference in phenotype is related to whether the mutated cysteine residue is involved in either interchain- or intrachain-disulfide-bond formation. The effects of three cysteine mutations which are all located in the CK-domain of VWF, C2773S (type 2A(IID)), C2739Y (type 3), and C2754W (type 3), were studied by transient expression in 293T cells. Cotransfection of wild-type (wt) and C2773S VWF constructs reproduced the plasma phenotype of heterozygous type 2A(IID) patients, with normal to high levels of VWF antigen (VWF:Ag), absence of high-molecular-weight multimers, and the presence of intervening bands between the normal multimers.In contrast, single transfections of C2739Y or C2754W resulted in a quantitativeVWF defect with lowVWF:Ag levels, and co-transfections of wt and mutant constructs resulted in a 50% reduction of VWF:Ag and only a minor effect on VWF multimerization. We demonstrated N-terminal dimerization of VWF-C2773S and both Nand C-terminal dimerization of VWF-C2754W. Our data suggest that loss of a single disulfide bond in the CK-domain ofVWF leads toa recessive, quantitativeVWF deficiency if an intrachain-disulfide bond is involved, and to a dominant-negative, qualitative defect of VWF if an interchain-disulfide bond is involved.


Author(s):  
И.В. Куртов ◽  
Е.С. Фатенкова ◽  
Н.А. Юдина ◽  
А.М. Осадчук ◽  
И.Л. Давыдкин

Болезнь Виллебранда (БВ) может представлять определенные трудности у рожениц с данной патологией. Приведены 2 клинических примера использования у женщин с БВ фактора VIII свертывания крови с фактором Виллебранда, показана эффективность и безопасность их применения. У одной пациентки было также показано использование фактора свертывания крови VIII с фактором Виллебранда во время экстракорпорального оплодотворения. Von Willebrand disease presents a certain hemostatic problem among parturients. This article shows the effectiveness and safety of using coagulation factor VIII with von Willebrand factor for the prevention of bleeding in childbirth in 2 patients with type 3 von Willebrand disease. In one patient, the use of coagulation factor VIII with von Willebrand factor during in vitro fertilization was also shown.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3101-3101
Author(s):  
Yoshihiko Sakurai ◽  
Midori Shima ◽  
Shogo Kasuda ◽  
Shoko Omura ◽  
Masahiro Takeyama ◽  
...  

Abstract Background: The replacement therapy with plasma-derived factor VIII (FVIII)/von Willebrand factor (VWF) concentrates is the first line treatment for the patients with type 3 von Willebrand disease (VWD). However, development of anti-VWF alloantibodies (inhibitor) is a major problem since the inhibitor neutralizes the VWF activity and may cause anaphylactic reactions. As an alternative treatment, the usage of FVIII concentrates has been reported but the mechanism of the hemostatic effects remains to be elucidated. Objectives: The purpose of this study is to address the role of FVIII in the hemostatic mechanism in the absence of VWF by in vitro and ex vivo analysis in the treatment for type 3 VWD with recombinant FVIII (rFVIII). Patient/Methods: The patient is a 55-year-old male with type 3 VWD. Blood samples were obtained before and 30 min after bolus administration. Rotating thromboelastometry (ROTEM) assay was performed to examine global interactions in hemostasis. To elucidate the effect on platelet activation, α-thrombin- and shear-induced platelet aggregation studies were performed. Further, α-thrombin-induced [Ca2+]i rise was assessed using fura2-AM loaded platelets. Results and Implications: The patient underwent two surgical procedures of multiple teeth extractions successfully with minimal bleeding by bolus administration of rFVIII (50 IU/kg) before procedure and followed by continuous infusion at rate of 10 IU/kg/h for 15 hours. FVIII:C was elevated from 1.0% to 20~30% 30 min after bolus infusion and maintained ~15% after 12 h-continuous infusion. ROTEM analysis showed that infusion of rFVIII shortened clotting time (preinfusion 2083.8±784.3 sec vs. post-infusion 1022.0±191.5 sec) and clot formation time (pre 1267.3±455.4 sec vs. post 705.8±261.8 sec) and increased α (pre 8.5±7.4 degree vs. post 23.5±4.4 degree). The α value and CFT indicate the rate of increase of elastic shear modulus. Addition of rFVIII to preinfusion blood in vitro corrected ROTEM parameters and thrombin-induced aggregation dose-dependently. Infusion of FVIII enhanced thrombin-induced platelet aggregation (% maximal aggregation: pre 26.3% vs. post 98.2%) as well as low shear-induced platelet aggregation (% maximal aggregation: pre 18% vs. post 52%). Furthermore, infusion of rFVIII meliorated thrombin-induced intracellular calcium flux of washed platelets (thrombin 10 nM, Ca flux: pre 414.0 nM vs. post 620.6 nM). Recently, the cell-based model of hemostasis provides a solid foundation for the relation between platelet and coagulation. Although coagulation initiation occurs normally via the extrinsic pathway, amplification mediated by the intrinsic pathway is seriously disturbed in type 3 VWD due to the marked decrease in FVIII. Therefore, correction of FVIII could result in the improvement of hemostasis. Our data demonstrated the effectiveness of FVIII in the surgical treatment for type 3 VWD and further suggested that FVIII molecules are incorporated into platelet phospholipids to facilitate platelet activation as well as act directly to intrinsic pathways to normalize coagulation. Conclusions: Our observations suggested that FVIII plays an essential role in hemostasis in the absence of VWF and provided the rationale for the usage of rFVIII in the hemostatic management of type 3 VWD.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. sci-46-sci-46
Author(s):  
J. Evan Sadler

Von Willebrand factor (VWF) plays a central role in hemostasis, and dysregulation of VWF can cause either bleeding or thrombosis. Endothelial cells assemble VWF multimers in two stages that occur in distinct intracellular compartments: proVWF subunits dimerize in the endoplasmic reticulum through “tail-to-tail” disulfide bonds between C-terminal CK domains, and the proVWF dimers form enormous multimers in the Golgi through “head-to-head” disulfide bonds between N-terminal D3 domains. The finished multimers are packaged into ordered tubules within storage organelles called Weibel-Palade bodies (WPB), and tubular packing is necessary for the secretion of VWF filaments that have normal hemostatic function. We have recreated VWF tubule assembly in vitro, starting with pure VWF propeptide (domains D1D2) and disulfide-linked dimers of adjacent N-terminal D’D3 domains. No other cellular proteins or components of WPB are needed. Assembly requires low pH and calcium ions, similar to conditions in the Golgi. Quick-freeze deep-etch electron microscopy and three-dimensional reconstruction of negatively stained images show that tubules contain a repeating unit of one D’D3 dimer and two propeptides arranged in a right-handed helix with 4.2 units per turn. The symmetry and location of interdomain contacts suggest that decreasing pH along the secretory pathway coordinates the disulfide-linked assembly of VWF multimers with their tubular packaging. Secretion into the blood exposes VWF tubules to neutral pH conditions, releasing the constraints that maintain tubular packing and permitting the orderly unfurling of large VWF multimers. Some VWF multimers bind platelets and initiate the growth of platelet-rich thrombi. Under normal circumstances, these thrombi are limited in size by ADAMTS13, a metalloprotease that cleaves VWF multimers and releases the platelets. The absence of large VWF multimers causes bleeding that is typical of von Willebrand disease. Conversely, congenital or acquired deficiency of ADAMTS13 prevents the dissolution of VWF-platelet aggregates, which can cause the widespread microvascular thrombosis that characterizes thrombotic thrombocytopenic purpura (TTP). Interestingly, ADAMTS13 deficiency alone need not trigger TTP. Some patients persist for months or years without active disease but become ill whenever they suffer additional inflammatory stress associated with infection, surgery, or pregnancy. Thus, interactions between inflammatory mediators and endothelial cells can determine the course of VWF-dependent thrombosis. The mechanisms responsible for these phenomena remain poorly understood.


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 ◽  
1987 ◽  
Vol 70 (4) ◽  
pp. 1214-1217
Author(s):  
E Fressinaud ◽  
D Baruch ◽  
C Rothschild ◽  
HR Baumgartner ◽  
D Meyer

Although it is well established that plasma von Willebrand Factor (vWF) is essential to platelet adhesion to subendothelium at high shear rates, the role of platelet vWF is less clear. We studied the respective role of both plasma and platelet vWF in mediating platelet adhesion to fibrillar collagen in a parallel-plate perfusion chamber. Reconstituted blood containing RBCs, various mixtures of labeled washed platelets and plasma from controls or five patients with severe von Willebrand disease (vWD), was perfused through the chamber for five minutes at a shear rate of 1,600 s-1. Platelet-collagen interactions were estimated by counting the radioactivity in deposited platelets and by quantitative morphometry. When the perfusate consisted of normal platelets suspended in normal plasma, platelet deposition on the collagen was 24.7 +/- 3.6 X 10(6)/cm2 (mean +/- SEM, n = 6). Significantly less deposition (16 +/- 2.3) was observed when vWD platelets were substituted for normal platelets. In mixtures containing vWD plasma, significantly greater deposition (9 +/- 2.2) was obtained with normal than with vWD platelets (1 +/- 0.4) demonstrating a role for platelet vWF in mediating the deposition of platelets on collagen. Morphometric analysis confirmed these data. Our findings indicate that platelet, as well as plasma, vWF mediates platelet-collagen interactions at a high shear rate.


2021 ◽  
Author(s):  
Andrew Yee ◽  
Manhong Dai ◽  
Stacy E. Croteau ◽  
Jordan A. Shavit ◽  
Steven W. Pipe ◽  
...  

SummaryBackgroundCorrection of von Willebrand factor (VWF) deficiency with replacement products containing VWF can lead to the development of anti-VWF alloantibodies (i.e., VWF inhibitors) in patients with severe von Willebrand disease (VWD).ObjectiveLocate inhibitor-reactive regions within VWF using phage display.MethodsWe screened a phage library displaying random, overlapping fragments covering the full length VWF protein sequence for binding to a commercial anti-VWF antibody or to immunoglobulins from three type 3 VWD patients who developed VWF inhibitors in response to treatment with plasma-derived VWF. Immunoreactive phage clones were identified and quantified by next generation DNA sequencing (NGS).ResultsNGS markedly increased the number of phage analyzed for locating immunoreactive regions within VWF following a single round of selection and identified regions not recognized in previous reports using standard phage display methods. Extending this approach to characterize VWF inhibitors from three type 3 VWD patients (including two siblings homozygous for the same VWF gene deletion) revealed patterns of immunoreactivity distinct from the commercial antibody and between unrelated patients, though with notable areas of overlap. Alloantibody reactivity against the VWF propeptide is consistent with incomplete removal of the propeptide from plasma-derived VWF replacement products.ConclusionThese results demonstrate the utility of phage display and NGS to characterize diverse anti-VWF antibody reactivities.


2021 ◽  
Vol 14 (8) ◽  
pp. e241613
Author(s):  
Vaishnavi Divya Nagarajan ◽  
Asha Shenoi ◽  
Lucy Burgess ◽  
Vlad C Radulescu

An 18-year-old man with a history of type 3 von Willebrand disease (VWD) presented with a spontaneous pyohaemothorax. Type 3 VWD may present with both mucocutaneous and deep-seated bleeds, such as visceral haemorrhages, intracranial bleeds and haemarthrosis. There have been very few cases described in children of spontaneous pyohaemothorax. Management of this patient was challenging due to risks of bleeding following surgical drainage, requiring constant replacement with von Willebrand factor concentrate, while monitoring factor VIII levels to balance the risks of thrombosis.


2020 ◽  
Vol 31 (1) ◽  
pp. 77-79
Author(s):  
Barbara Faganel Kotnik ◽  
Karin Strandberg ◽  
Maruša Debeljak ◽  
Lidija Kitanovski ◽  
Janez Jazbec ◽  
...  

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