scholarly journals Gamma-interferon modulates von Willebrand factor release by cultured human endothelial cells

Blood ◽  
1990 ◽  
Vol 75 (11) ◽  
pp. 2177-2184 ◽  
Author(s):  
SH Tannenbaum ◽  
HR Gralnick
Keyword(s):  
Molecular Weight ◽  
Endothelial Cells ◽  
High Molecular Weight ◽  
Von Willebrand Factor ◽  
Inflammatory Mediators ◽  
Interleukin 1 ◽  
Gamma Interferon ◽  
Human Endothelial Cells ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract Endothelial cells (EC) synthesize and secrete von Willebrand factor (vWF), a multimeric glycoprotein required for normal hemostasis. Within human endothelial cells, vWF multimers of extremely high molecular weight are stored in rod-shaped organelles known as Weibel-Palade bodies. Inflammatory mediators, such as interleukin-1, induce in vitro a variety of procoagulant responses by EC, including the secretion of stored vWF. We postulated that other inflammatory mediators might act to balance this procoagulant reaction, thereby assisting in the maintenance of blood fluidity during immune activation. Both gamma- interferon (gamma-IFN) and tumor necrosis factor (TNF) were found to act independently and cooperatively to depress the stimulated release of vWF from EC. Analysis of stored vWF in either gamma-IFN and/or TNF- treated EC demonstrated a loss of high molecular weight multimers while immunofluorescent studies documented a loss of visible Weibel-Palade bodies. This suggests that gamma-IFN and TNF interfere with normal vWF storage. gamma-IFN acted in a dose-, time-, and RNA-dependent fashion, and its inhibition of vWF release was reversible with time. No effect of gamma-IFN on EC was noted when anti-serum to gamma-IFN was added. Unlike gamma-IFN, alpha-interferon did not effect EC vWF. Therefore, gamma-IFN and TNF may be important in decreasing vWF release during inflammatory or immunologic episodes.

scholarly journals Gamma-interferon modulates von Willebrand factor release by cultured human endothelial cells

Blood ◽  
1990 ◽  
Vol 75 (11) ◽  
pp. 2177-2184
Author(s):  
SH Tannenbaum ◽  
HR Gralnick
Keyword(s):  
Molecular Weight ◽  
Endothelial Cells ◽  
High Molecular Weight ◽  
Von Willebrand Factor ◽  
Inflammatory Mediators ◽  
Interleukin 1 ◽  
Gamma Interferon ◽  
Human Endothelial Cells ◽  
Von Willebrand ◽  
Willebrand Factor

Endothelial cells (EC) synthesize and secrete von Willebrand factor (vWF), a multimeric glycoprotein required for normal hemostasis. Within human endothelial cells, vWF multimers of extremely high molecular weight are stored in rod-shaped organelles known as Weibel-Palade bodies. Inflammatory mediators, such as interleukin-1, induce in vitro a variety of procoagulant responses by EC, including the secretion of stored vWF. We postulated that other inflammatory mediators might act to balance this procoagulant reaction, thereby assisting in the maintenance of blood fluidity during immune activation. Both gamma- interferon (gamma-IFN) and tumor necrosis factor (TNF) were found to act independently and cooperatively to depress the stimulated release of vWF from EC. Analysis of stored vWF in either gamma-IFN and/or TNF- treated EC demonstrated a loss of high molecular weight multimers while immunofluorescent studies documented a loss of visible Weibel-Palade bodies. This suggests that gamma-IFN and TNF interfere with normal vWF storage. gamma-IFN acted in a dose-, time-, and RNA-dependent fashion, and its inhibition of vWF release was reversible with time. No effect of gamma-IFN on EC was noted when anti-serum to gamma-IFN was added. Unlike gamma-IFN, alpha-interferon did not effect EC vWF. Therefore, gamma-IFN and TNF may be important in decreasing vWF release during inflammatory or immunologic episodes.

scholarly journals Composition of the von Willebrand factor storage organelle (Weibel-Palade body) isolated from cultured human umbilical vein endothelial cells.

1987 ◽  
Vol 104 (5) ◽  
pp. 1423-1433 ◽  
Author(s):  
B M Ewenstein ◽  
M J Warhol ◽  
R I Handin ◽  
J S Pober
Keyword(s):  
Molecular Weight ◽  
Endothelial Cells ◽  
High Molecular Weight ◽  
Von Willebrand Factor ◽  
Umbilical Vein ◽  
Proteolytic Processing ◽  
Storage Organelle ◽  
Umbilical Vein Endothelial Cells ◽  
Von Willebrand ◽  
Willebrand Factor

von Willebrand factor (VWF) is a large, adhesive glycoprotein that is biosynthesized and secreted by cultured endothelial cells (EC). Although these cells constitutively release VWF, they also contain a storage pool of this protein that can be rapidly mobilized. In this study, a dense organelle fraction was isolated from cultured umbilical vein endothelial cells by centrifugation on a self-generated Percoll gradient. Stimulation of EC by 4-phorbol 12-myristate 13-acetate (PMA) resulted in the disappearance of this organelle fraction and the synchronous loss of Weibel-Palade bodies as judged by immunoelectron microscopy. Electrophoretic and serologic analyses of biosynthetically labeled dense organelle fraction revealed that it is comprised almost exclusively of VWF and its cleaved pro sequence. These two polypeptides were similarly localized exclusively to Weibel-Palade bodies by ultrastructural immunocytochemistry. The identity of the dense organelle as the Weibel-Palade body was further established by direct morphological examination of the dense organelle fraction. The VWF derived from this organelle is distributed among unusually high molecular weight multimers composed of fully processed monomeric subunits and is rapidly and quantitatively secreted in unmodified form after PMA stimulation. These studies: establish that the Weibel-Palade body is the endothelial-specific storage organelle for regulated VWF secretion; demonstrate that in cultured EC, the VWF concentrated in secretory organelles is of unusually high molecular weight and that this material may be rapidly mobilized in unmodified form; imply that proteolytic processing of VWF involved in regulated secretion takes place after translocation to the secretory organelle; provide a basis for further studies of intracellular protein trafficking in EC.

VON WILLEBRAND FACTOR MULTIMERS IN CULTURED HUMAN ENDOTHELIAL CELLS: COMPARISON BETWEEN CELLULAR STORAGE POOL AND SUPERNATANT

1987 ◽  
Author(s):  
F Piovella ◽  
R Lombardi ◽  
M Vigotti ◽  
A B Federici ◽  
P M Mannucci ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Endothelial Cells ◽  
Von Willebrand Factor ◽  
Sodium Dodecyl ◽  
Calf Serum ◽  
Foetal Calf Serum ◽  
Human Endothelial Cells ◽  
Von Willebrand ◽  
Culture Supernatants ◽  
Willebrand Factor

The multimeric composition of von Willebrand factor (vWf) from cultured human endothelial cells (h.e.c.) has been compared with the multimeric composition of vWf from h.e.c. culture supernatant, human normal platelets and plasma. H.e.c. were derived from umbilical cord veins by collagenase digestion, seeded in culture flasks and grown to confluence in TC 199 culture medium, supplemented with 20% foetal calf serum (FCS). At confluency, cells were harvested by rubber policeman, resuspended in 500 |o.l HBSS with protease inhibitors and stored with culture media until assay. H.e.c. and platelet lysates were obtained by freezing-and-thawing (5 times) and by the addition of 1% Sodium Dodecyl Sulphate (SDS) before centrifugation at 10,000 x g for 20 min at 20°C. Plasma, culture supernatants and cell lysates supernatants were run under the same conditions in an SDS 1.4%, LGT-agarose electrophoresis system using a discontinous buffer. Multimeric patterns were shown by radiolabelled affinity purified rabbit anti-human polyclonal antibody. In all the experiments cultured h.e.c. supernatants exhibited all the set of multimers of vWf usually observed in normal plasma. When vWf from cultured h.e.c. extracts was analyzed, a set of multimers with higher molecular weight was shown, with a pattern very similar to platelet's. We conclude that vWf stored in h.e.c. compartments is characterized by higher molecular weight multimers than culture supernatants. This behaviour recalls the differences recorded between plasma and platelet vWf.

A novel von Willebrand disease–causing mutation (Arg273Trp) in the von Willebrand factor propeptide that results in defective multimerization and secretion

Blood ◽  
2000 ◽  
Vol 96 (2) ◽  
pp. 560-568 ◽  
Author(s):  
Simon Allen ◽  
Adel M. Abuzenadah ◽  
Joanna Hinks ◽  
Joanna L. Blagg ◽  
Turkiz Gursel ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Von Willebrand Factor ◽  
Family Members ◽  
Amino Acid Position ◽  
Von Willebrand Disease ◽  
Molecular Defect ◽  
Wild Type ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract In this report we describe the molecular defect underlying partial and severe quantitative von Willebrand factor (VWF) deficiencies in 3 families previously diagnosed with types 1 and 3 Von Willebrand-disease. Analysis of the VWF gene in affected family members revealed a novel C to T transition at nucleotide 1067 of the VWF complemetary DNA (cDNA), predicting substitution of arginine by tryptophan at amino acid position 273 (R273W) of pre–pro-VWF. Two patients, homozygous for the R273W mutation, had a partial VWF deficiency (VWF:Ag levels of 0.06 IU/mL and 0.09 IU/mL) and lacked high-molecular weight VWF multimers in plasma. A third patient, also homozygous for the R273W mutation, had a severe VWF deficiency (VWF:Ag level of less than 0.01 IU/mL) and undetectable VWF multimers in plasma. Recombinant VWF having the R273W mutation was expressed in COS-7 cells. Pulse-chase experiments showed that secretion of rVWFR273W was severely impaired compared with wild-type rVWF. However, the mutation did not affect the ability of VWF to form dimers in the endoplasmic reticulum (ER). Multimer analysis showed that rVWFR273W failed to form high-molecular-weight multimers present in wild-type rVWF. We concluded that the R273W mutation is responsible for the quantitative VWF deficiencies and aberrant multimer patterns observed in the affected family members. To identify factors that may function in the intracellular retention of rVWFR273W, we investigated the interactions of VWF expressed in COS-7 cells with molecular chaperones of the ER. The R273W mutation did not affect the ability of VWF to bind to BiP, Grp94, ERp72, calnexin, and calreticulin in COS-7 cells.

scholarly journals Differential regulation by cytokines of constitutive and stimulated secretion of von Willebrand factor from endothelial cells

Blood ◽  
1990 ◽  
Vol 75 (3) ◽  
pp. 688-695 ◽  
Author(s):  
EM Paleolog ◽  
DC Crossman ◽  
JH McVey ◽  
JD Pearson
Keyword(s):  
Endothelial Cells ◽  
Von Willebrand Factor ◽  
Messenger Rna ◽  
Cell Injury ◽  
Interleukin 1 ◽  
Tnf Alpha ◽  
Detectable Effect ◽  
Dependent Manner ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract We examined the effect of cytokines on basal and agonist-stimulated release of von Willebrand factor (vWf) by human endothelial cells. Treatment of endothelial cells for up to 48 hours with human recombinant or purified interleukin 1 (IL-1) or human recombinant tumor necrosis factor-alpha (TNF-alpha) did not significantly affect constitutive secretion of vWf or intracellular levels of vWf, although basal prostacyclin (PGI2) production was markedly enhanced. In contrast, both IL-1 and TNF-alpha modulated vWf release in response to thrombin or phorbol ester. Pretreatment of endothelial cells for 2 hours with either cytokine enhanced by up to threefold the stimulatory effect of a subsequent 60-minute exposure to thrombin. Addition of cycloheximide (5 micrograms/mL) during the preincubation abolished this enhancement. Moreover, if the cytokine pretreatment time was extended to 24 hours, agonist-stimulated vWf release was significantly suppressed. Cytokine treatment for 2 or 24 hours had no detectable effect on levels of vWf messenger RNA. The effects of cytokines were not the result of contamination with bacterial lipopolysaccharide and were not attributable to endothelial cell injury. These results show that cytokines have little or no direct effect on vWf release from endothelial cells but can significantly modulate its acute release in response to other stimuli in a complex time- and dose-dependent manner.

Sign in / Sign up

Export Citation Format

Share Document