Regulation of von Willebrand Factor Gene in Endothelial Cells That Are Programmed to Pluripotency and Differentiated Back to Endothelial Cells

SummaryBiosynthesis of the adhesive glycoprotein von Willebrand factor (vWf) by endothelial cells results in constitutive secretion of small multimers and storage of the largest multimers in rodshaped granules called Weibel-Palade bodies. This pattern is reproduced by expression of pro-vWf in heterologous cells with a regulated pathway of secretion, that store the recombinant protein in similar elongated granules. In these cells, deletion of the vWf prosequence prevents vWf storage. The prosequence, composed of two homologous domains (D1 and D2), actively participates in vWf multimer formation as well. We expressed deletion mutants lacking either the D1 domain (D2vWf) or the D2 domain (D1vWf) in various cell lines to analyze the relative importance of each domain in vWf muitimerization and storage. Both proteins were secreted efficiently without being retained in the endoplasmic reticulum. Despite this, neither multimerized past the dimer stage and they were not stored. We conclude that several segments of the prosequence are jointly involved in vWf muitimerization and storage.

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

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651575 ◽

1993 ◽

Vol 69 (02) ◽

pp. 173-176 ◽

Cited By ~ 5

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.

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Adverse Influence of Cigarette Smoking on the Endothelium

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649654 ◽

1993 ◽

Vol 70 (04) ◽

pp. 707-711 ◽

Cited By ~ 77

Author(s):

Andrew D Blann ◽

Charles N McCollum

Keyword(s):

Endothelial Cells ◽

Von Willebrand Factor ◽

Tobacco Smoke ◽

Lipid Peroxides ◽

Short Exposure ◽

Acute Effects ◽

Adverse Influence ◽

Von Willebrand ◽

Willebrand Factor

SummaryThe effect of smoking on the blood vessel intima was examined by comparing indices of endothelial activity in serum from smokers with that from non-smokers. Serum from smokers contained higher levels of von Willebrand factor (p <0.01), the smoking markers cotinine (p <0.02) and thiocyanate (p <0.01), and was more cytotoxic to endothelial cells in vitro (p <0.02) than serum from non-smokers. The acute effects of smoking two unfiltered medium tar cigarettes was to briefly increase von Willebrand factor (p <0.001) and cytotoxicity of serum to endothelial cells in vitro (p <0.005), but lipid peroxides or thiocyanate were not increased by this short exposure to tobacco smoke. Although there were correlations between von Willebrand factor and smokers consumption of cigarettes (r = 0.28, p <0.02), number of years smoking (r = 0.41, p <0.001) and cotinine (r = 0.45, p <0.01), the tissue culture of endothelial cells with physiological levels of thiocyanate or nicotine suggested that these two smoking markers were not cytotoxic. They are therefore unlikely to be directly responsible for increased von Willebrand factor in the serum of smokers. We suggest that smoking exerts a deleterious influence on the endothelium and that the mechanism is complex.

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Characterization of Partial Gene Deletions in Type III von Willebrand Disease with Alloantibody Inhibitors

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648835 ◽

1994 ◽

Vol 72 (02) ◽

pp. 180-185 ◽

Cited By ~ 22

Author(s):

David J Mancuso ◽

Elodee A Tuley ◽

Ricardo Castillo ◽

Norma de Bosch ◽

Pler M Mannucci ◽

...

Keyword(s):

Von Willebrand Factor ◽

Von Willebrand Disease ◽

Pcr Analysis ◽

Gene Deletions ◽

Factor Gene ◽

Type Iii ◽

Large Deletions ◽

Von Willebrand ◽

Willebrand Factor

Summaryvon Willebrand factor gene deletions were characterized in four patients with severe type III von Willebrand disease and alloantibodies to von Willebrand factor. A PCR-based strategy was used to characterize the boundaries of the deletions. Identical 30 kb von Willebrand factor gene deletions which include exons 33 through 38 were identified in two siblings of one family by this method. A small 5 base pair insertion (CCTGG) was sequenced at the deletion breakpoint. PCR analysis was used to detect the deletion in three generations of the family, including two family members who are heterozygous for the deletion. In a second family, two type III vWD patients, who are distant cousins, share an -56 kb deletion of exons 22 through 43. The identification and characterization of large vWF gene deletions in these type III vWD patients provides further support for the association between large deletions in both von Willebrand factor alleles and the development of inhibitory alloantibodies.

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Venous Occlusion Does Not Release von Willebrand Factor, Factor VIII or PAI-1 from Endothelial Cells – The Importance of Consensus on the Use of Correction Factors for Haemoconcentration

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651559 ◽

1993 ◽

Vol 69 (01) ◽

pp. 091-091 ◽

Cited By ~ 15

Author(s):

Iwona Wieczorek ◽

Christopher A Ludlam ◽

Ian MacGregor

Keyword(s):

Endothelial Cells ◽

Factor Viii ◽

Von Willebrand Factor ◽

Venous Occlusion ◽

Correction Factors ◽

Von Willebrand ◽

Willebrand Factor ◽

Pai 1

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Epinephrine Induces von Willebrand Factor Release from Cultured Endothelial Cells: Involvement of Cyclic AMP-dependent Signalling in Exocytosis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656135 ◽

1997 ◽

Vol 77 (06) ◽

pp. 1182-1188 ◽

Cited By ~ 74

Author(s):

Ulrich M Vischer ◽

Claes B Wollheinn

Keyword(s):

Endothelial Cells ◽

Adenylate Cyclase ◽

Von Willebrand Factor ◽

Umbilical Vein ◽

Free Calcium ◽

Camp Content ◽

Von Willebrand ◽

Willebrand Factor

Summaryvon Willebrand factor (vWf) is released from endothelial cell storage granules after stimulation with thrombin, histamine and several other agents that induce an increase in cytosolic free calcium ([Ca2+]i). In vivo, epinephrine and the vasopressin analog DDAVP increase vWf plasma levels, although they are thought not to induce vWf release from endothelial cells in vitro. Since these agents act via a cAMP-dependent pathway in responsive cells, we examined the role of cAMP in vWf secretion from cultured human umbilical vein endothelial cells. vWf release increased by 50% in response to forskolin, which activates adenylate cyclase. The response to forskolin was much stronger when cAMP degradation was blocked with IBMX, an inhibitor of phosphodiesterases (+200%), whereas IBMX alone had no effect. vWf release could also be induced by the cAMP analogs dibutyryl-cAMP (+40%) and 8-bromo-cAMP (+25%); although their effect was weak, they clearly potentiated the response to thrombin. Epinephrine (together with IBMX) caused a small, dose-dependent increase in vWf release, maximal at 10-6 M (+50%), and also potentiated the response to thrombin. This effect is mediated by adenylate cyclase-coupled β-adrenergic receptors, since it is inhibited by propranolol and mimicked by isoproterenol. In contrast to thrombin, neither forskolin nor epinephrine caused an increase in [Ca2+]j as measured by fura-2 fluorescence. In addition, the effects of forskolin and thrombin were additive, suggesting that they act through distinct signaling pathways. We found a close correlation between cellular cAMP content and vWf release after stimulation with epinephrine and forskolin. These results demonstrate that cAMP-dependent signaling events are involved in the control of exocytosis from endothelial cells (an effect not mediated by an increase in [Ca2+]i) and provide an explanation for epinephrine-induced vWf release.

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