The Vascular Endothelium in Patients with Dengue Haemorrhagic Fever

BACKGROUND: Dengue fever is the most serious consequence of mosquito-borne infection worldwide. The pathophysiology of DHF in human is complex, which involve endothelial cell activation and impaired endothelial barrier leading to plasma leakage triggering the activation of the haemostatic system. The increased vascular permeability may lead to hypovolemia, hypotension and shock, which is life-threatening. AIM: The objective of the study was to determine the effects of dengue haemorrhagic fever on the vascular endothelium. METHODS: Fifty patients (males 34, females 16), were recruited, Grade 1 (n = 41), Grade 2 (n = 6), Grade 3 (n = 2) and Grade 4 (n = 1) DHF. Blood sampling was performed at the febrile, defervescence and convalescent phases for the determination of haemoglobin, haematocrit, platelets, prothrombin fragment F1 + 2, Von Willebrand Factor (VWF), vascular endothelial growth factor (VEGF) and D-dimer levels. Fifteen normal subjects were recruited to serve as normal controls. RESULTS: The patients aged between 4 and 54 years old. Grades 1 & 2 DHF showed no significant differences in the parameters studied. However, thrombocytopenia, elevated F1 + 2, VWF, VEGF and D-dimer levels were evident in febrile, defervescence and convalescent phases suggesting endothelial activation and plasma leakage. Pleural effusion was observed only in severe DHF. The three patients with Grades 3 and 4 DHF had similar study results. No mortality was recorded in the study. CONCLUSION: In dengue haemorrhagic fever, the vascular endothelium is activated, causing plasma leakage triggering the activation of the haemostatic system creating a hypercoagulable and enhanced fibrinolytic state evident by marked fibrinolysis.

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Abstract 66: The Role of the Viral Nef Protein as a Mediator of HIV-1--Induced Endothelial Dysfunction

Circulation Research ◽

10.1161/res.111.suppl_1.a66 ◽

2012 ◽

Vol 111 (suppl_1) ◽

Author(s):

Ting Wang

Keyword(s):

Cardiovascular Disease ◽

T Cells ◽

Endothelial Cells ◽

Endothelial Cell ◽

Endothelial Dysfunction ◽

Binding Site ◽

Cell Activation ◽

Endothelial Activation ◽

Endothelial Cell Activation ◽

Hiv 1

With the prevalence of antiviral therapy in the developed world, many HIV-1-infected people die of diseases other than AIDS. One of the emerging major causes is cardiovascular disease, leading to the prediction that the majority of HIV-1 patients are expected to develop cardiovascular complications. Endothelial dysfunction is thought to be a key event in the development of cardiovascular diseases, particularly atherosclerosis. Assays testing the effect of HIV-1 on endothelial activation shows that direct contact with HIV-1 infected T cells enhance endothelial cell activation to a greater extent than HIV-1 alone, suggesting an intracellular HIV-1 protein is responsible for endothelial activation. The HIV-1 viral protein Nef, which is responsible for T cell activation and maintenance of high viral loads in vivo , has been shown to mediate its own transfer to bystander cells. We demonstrate here for the first time that Nef induces nanotube-like conduits connecting T cells and endothelial cells. We also show that Nef is transferred from T cells to endothelial cells via these nanotubes, and is necessary and sufficient for endothelial cell activation. Moreover, we show that SIV-infected macaques exhibit endothelial Nef expression in coronary arteries. Nef expression in endothelial cells causes endothelial apoptosis, ROS and MCP-1 production. Interestingly, a Nef SH3 binding site mutant abolishes Nef-induced apoptosis and ROS formation and reduces MCP-1 production in endothelial cells, suggesting that the Nef SH3 binding site is critical for Nef effects on endothelial cells. Nef induces apoptosis of endothelial cells through an NADPH oxidase- and ROS-dependent mechanism, while Nef-induced MCP-1 production is NF-kB dependent. Taken together, these data suggest that Nef can mediate its transfer from T cells to endothelial cells through nanotubes to enhance endothelial dysfunction.Thus, Nef is a promising new therapeutic target for reducing the risk for cardiovascular disease in the HIV-1 positive population.

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Brucella abortus-Stimulated Platelets Activate Brain Microvascular Endothelial Cells Increasing Cell Transmigration through the Erk1/2 Pathway

Pathogens ◽

10.3390/pathogens9090708 ◽

2020 ◽

Vol 9 (9) ◽

pp. 708

Author(s):

Ana María Rodríguez ◽

Aldana Trotta ◽

Agustina P. Melnyczajko ◽

M. Cruz Miraglia ◽

Kwang Sik Kim ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Brucella Abortus ◽

Cell Activation ◽

Transendothelial Migration ◽

Endothelial Activation ◽

Microvascular Endothelial Cell ◽

Inflammatory Disorder ◽

Endothelial Cell Activation ◽

Microvascular Endothelial

Central nervous system invasion by bacteria of the genus Brucella results in an inflammatory disorder called neurobrucellosis. A common feature associated with this pathology is blood–brain barrier (BBB) activation. However, the underlying mechanisms involved with such BBB activation remain unknown. The aim of this work was to investigate the role of Brucella abortus-stimulated platelets on human brain microvascular endothelial cell (HBMEC) activation. Platelets enhanced HBMEC activation in response to B. abortus infection. Furthermore, supernatants from B. abortus-stimulated platelets also activated brain endothelial cells, inducing increased secretion of IL-6, IL-8, CCL-2 as well as ICAM-1 and CD40 upregulation on HBMEC compared with supernatants from unstimulated platelets. Outer membrane protein 19, a B. abortus lipoprotein, recapitulated B. abortus-mediated activation of HBMECs by platelets. In addition, supernatants from B. abortus-activated platelets promoted transendothelial migration of neutrophils and monocytes. Finally, using a pharmacological inhibitor, we demonstrated that the Erk1/2 pathway is involved in the endothelial activation induced by B. abortus-stimulated platelets and also in transendothelial migration of neutrophils. These results describe a mechanism whereby B. abortus-stimulated platelets induce endothelial cell activation, promoting neutrophils and monocytes to traverse the BBB probably contributing to the inflammatory pathology of neurobrucellosis.

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Changes in ADAMTS 13 Activity and Von Willebrand Factor Parameters during Acute Dengue Infection.

Blood ◽

10.1182/blood.v108.11.1492.1492 ◽

2006 ◽

Vol 108 (11) ◽

pp. 1492-1492

Author(s):

Darintr Sosothikul ◽

Panya Seksarn ◽

Sureeporn Pongsawaluk ◽

Jeanne M. Lusher

Keyword(s):

Von Willebrand Factor ◽

Cell Activation ◽

Dengue Infection ◽

Plasma Concentrations ◽

Endothelial Activation ◽

Healthy Children ◽

Endothelial Cell Activation ◽

Convalescent Phase ◽

Von Willebrand ◽

Willebrand Factor

Abstract Dengue virus causes febrile illnesses: Dengue Fever (DF) and less frequently a life-threatening illness, Dengue Hemorrhagic Fever (DHF). The pathophysiology of hemostatic defect in dengue infection is thought to relate to the direct effect of virus or cytokines on endothelial activation. To study the state of endothelial activation during dengue infection, we measured plasma levels of von Willebrand factor antigen (vWF:Ag), vWF-collagen binding assay (vWF:CBA), and ADAMTS 13 activity in 42 children (20 with DF and 22 with DHF) during 3 phases of illness: febrile, toxic, and convalescent phase. 38 healthy children comprised as controls. Our data shows that both VWF:Ag and vWF:CBA levels were significantly higher in dengue patients (p ≤ 0.001 in both DF and DHF patients) versus controls. DHF patients had significantly higher of VWF: Ag (p = 0.01, versus DF). ADAMTS 13 activity levels were significantly decreased only in DHF patients during 3 phases of the illness (febrile; mean 78%; p = 0.016, toxic; mean 68%; p<0.001 and convalescent; mean 69%; p<0.001 compared to mean 104% of the controls). Compared to DF patients, DHF patients had significantly lower plasma concentrations of ADAMTS 13 activity during the febrile, toxic and convalescent phase (p = 0.039, p = 0.002 and p =0.003, respectively). Endothelial cell activation is a hallmark of dengue infection especially in DHF patients; indicated by a significant rise in VWF:Ag and vWF:CBA and a reciprocal decline in ADAMTS 13 activity.

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Differences in the Coagulation Profile in Women with Mild and Severe Preeclampsia

Blood ◽

10.1182/blood-2020-137401 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 15-16

Author(s):

Elmina Lefkou ◽

Patrick Van Dreden ◽

Aurélie Rousseau ◽

Grigorios T. Gerotziafas

Keyword(s):

Pregnant Women ◽

Prothrombin Time ◽

Cell Activation ◽

Severe Preeclampsia ◽

Clotting Time ◽

Endothelial Cell Activation ◽

Mild Preeclampsia ◽

The Mean ◽

Group D ◽

D Dimer

Introduction:Different coagulations abnormalities have been referred in women with early oncet preeclampsia (EOP), but there are only few studies comparing those changes regarding to the severity of the disease. Aim:In this study we aimed to investigate the differences between the coagulation profile in women with mild and severe preeclampsia. Methods:This is an observational retrospective case-control study. Plasma samples were collected from 84 women divided into three groups, the healthy pregnant (HP) group (n=35), the mild preeclampsia (MP) group (n=34) and the severe preeclampsia (SP) group (n=15). The study population general characteristics are shown in Table 1. We studied the following biomarkers of hypercoagulability and endothelial cell activation: Tissue factor activity (TFa), Procoagulant phospholipid activity (PPL), Protein S, D-Dimers, Antithrombin, thrombomodulin, TFPI levels. All women were assessed with classic coagulation tests (aPTT and PT) fibrinogen levels and hemogram. Statistical analysis was performed using the PASW Statistics 17.0.2 (SPSS Inc.) for Windows. Results:Women with preeclampsia - mild or severe- showed significant increase of TFPI, TFa and TMa levels as compared to healthy pregnant women. No significant difference of TFPI, TFa was observed between MP and SP groups. In contrast, TMa levels were significantly increased in SP as compared to MP group. The ratio TFa/TFPI was also lower in SP as compared to MP-group. Women in MP or SP group had similarly shorter PPL clotting time as compared to HP group. D-dimer levels were increased in women with preeclampsia as compared to the HP group. D-Dimer levels were significantly higher in SP as compared to MP group. The levels of free PS activity in HP as well as MP and SP groups were lower than normal range in non-pregnant women and the value in MP was significantly lower than that of the HP or SP. Fibrinogen levels were not significantly different in the three studied groups of pregnant women. Prothrombin time was found to be increased in cases as compared to that in the controls. The mean value of prothrombin time in mild preeclampsia was 13.24±0.80 seconds and in severe preeclampsia it was seconds 14.77±0.96 and in pregnant controls 12.23±0.59 seconds (p<0.05 and p<0.001 respectively). The mean prothrombin time was found to increase with increasing severity of disease (p<0.001). The mean activated partial thromboplastin time were increased in mild preeclampsia and was 32.64±1.83 seconds and in severe preeclampsia it was 35.59±1.53 seconds and in pregnant controls 29.53±1.62 seconds (p<0.001). The activated partial thromboplastin time was found to increase with increasing severity of disease (p<0.001). The antithrombin III decreased in severe SP and MP or compared to pregnant controls (76.33±4.32 and 88.06±9.68 versus 95.40±0.36 respectively; p<0.001). This decrease is more pronounced in SP compared to MP (p<0.001). Conclusions:Preeclampsia is associated with endothelial cell activation as documented by the increase of TFa, soluble TM levels and TFPI levels in plasma. Release of soluble thrombomoduline and TFPI rather than TFa by endothelial cells appear to be related with degree of preeclampsia severity. Women with preeclampsia showed marked decrease of PPL clotting time indicating enhanced platelet activation that was independent of the severity of preeclampsia. In contrast, women with severe preeclampsia showed signs of enhanced hypercoagulability documented by the increase of D-dimer levels consumption of natural coagulation inhibitors and particularly of AT. This phenomenon tended to be reflected on the prolongation of PT and aPTT in women with severe preeclampsia. Disclosures No relevant conflicts of interest to declare.

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Polynitroxyl Albumin Prevents Vaso-Occlusion in Transgenic Sickle Mice.

Blood ◽

10.1182/blood.v104.11.366.366 ◽

2004 ◽

Vol 104 (11) ◽

pp. 366-366 ◽

Cited By ~ 1

Author(s):

Hemchandra Mahaseth ◽

John D. Belcher ◽

Thomas E. Welch ◽

Khalid M. Sonbol ◽

Paul R. Bowlin ◽

...

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Adhesion Molecule ◽

Vascular Endothelium ◽

Cell Activation ◽

Ros Production ◽

Dorsal Skin ◽

Cell Disease ◽

Endothelial Cell Activation ◽

Hypoxia Reoxygenation

Abstract Sickle cell disease is characterized by excessive oxidative stress. Sickle patients have enhanced rates of endogenous reactive oxygen species (ROS) production and impaired antioxidant defense mechanisms. We hypothesize that excessive production of ROS promotes activation of vascular endothelium and vaso-occlusion in sickle cell disease. Intravascular ROS production has been shown to trigger the activation of vascular endothelium and increase leukocyte-endothelium interactions. We investigated whether inhibition of intravascular ROS production by treatment with polynitroxyl albumin (PNA), a superoxide dismutase and catalase mimetic agent, could modulate endothelial cell activation and vaso-occlusion in S+S Antilles transgenic sickle mice after hypoxia-reoxygenation. Nuclear factor-kappa B (NF-kB), an oxidant sensitive transcription factor critical for endothelial cell activation, was elevated in lungs and livers of sickle mice and was reduced 2.5 (p=0.043) and 1.5 (p=0.043) fold respectively, by treatment with PNA after hypoxia-reoxygenation. Similarly, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were elevated 3 to 4.7 fold in the same organs (p<0.05). After treatment with PNA, VCAM-1 expression was reduced 2.3 fold in lungs (p=0.014) and 1.5 fold in livers (p=0.006), ICAM-1 expression decreased 1.7 fold in lungs (p=0.014) and 2 fold in livers (p=0.007). Control studies using human serum albumin had no effect on NF-kB activation or adhesion molecule expression in sickle mice. These anti-inflammatory effects of PNA on endothelium corresponded with changes in blood flow in dorsal skin venules. Intravital microscopy revealed that PNA significantly inhibited hypoxia-reoxygenation-induced leukocyte rolling (3.8 fold inhibition, p<0.001) and completely inhibited vaso-occlusion (p<0.001) in venules in the dorsal skin of transgenic sickle mice. We speculate that therapies that reduce ROS will result in improved organ perfusion in sickle cell disease.

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IL-35 Suppresses Lipopolysaccharide-Induced Endothelial Cell Activation Through Downregulation of MAPK Signaling-Mediated Upregulation of Adhesion Molecule VCAM-1

Blood ◽

10.1182/blood.v120.21.3310.3310 ◽

2012 ◽

Vol 120 (21) ◽

pp. 3310-3310

Author(s):

Xiaojin Sha ◽

Shu Meng ◽

Xinyuan Li ◽

Jahaira Lopez Pastrana ◽

Hong Wang ◽

...

Keyword(s):

Endothelial Cell ◽

Adhesion Molecule ◽

Cell Activation ◽

Conflicts Of Interest ◽

Vascular Inflammation ◽

Endothelial Activation ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Interleukin 12 ◽

Endothelial Cell Activation

Abstract Abstract 3310 Our previous reports showed that survival/apoptosis of CD4+CD25+Foxp3+ regulatory T cells (Tregs) modulates vascular inflammation even though the mode of Tregs inhibition was unknown. Interleukin-35 (IL-35), consisting of two subunits Epstein-Barr virus–induced gene 3 (EBI3) and p35, is a novel anti-inflammatory cytokine, which is a member of the interleukin-12 (IL-12) cytokine family. IL-35 is produced by Tregs. It has been shown that IL-35 suppresses chronic inflammatory diseases such as asthma and inflammatory bowel diseases. However, an important question of whether IL-35 can carry out Tregs suppression and inhibit endothelial cell (EC) activation in acute inflammation remained unknown. Here we found that IL-35 significantly inhibits lung neutrophil infiltration into the surrounding areas of bronchioles and alveolar space when induced by intraperitoneal injection of lipopolysaccharide (LPS) in wild type mice and EBI3-deficient mice. Furthermore, cremaster microvasculature study using intravital microscopy showed IL-35 significantly suppresses leukocyte adhesion to the vascular wall as well, suggesting IL-35 inhibition of endothelial activation. Mechanistically, IL-35 inhibited LPS-induced upregulation of adhesion molecules on human aortic endothelial cells, a marker of endothelial activation, including vascular cell adhesion molecule 1 (VCAM-1). IL-35 acted through new IL-35 dimeric receptors gp130 and IL-12Rβ2, and inhibited VCAM-1 promoter transcription in mitogen-activated protein kinase (MAPK)-mediated pathway. These results provide a novel insight on Tregs and IL-35 inhibition of vascular inflammation. Disclosures: No relevant conflicts of interest to declare.

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Models for the onset of plasma leakage in dengue haemorrhagic fever

Applied Mathematical Sciences ◽

10.12988/ams.2014.44286 ◽

2014 ◽

Vol 8 ◽

pp. 3709-3719 ◽

Cited By ~ 1

Author(s):

M. Kallista ◽

N. Nuraini ◽

L. Natalia ◽

E. Soewono

Keyword(s):

Dengue Haemorrhagic Fever ◽

Haemorrhagic Fever ◽

Plasma Leakage

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Soluble thrombomodulin reduces inflammation and prevents microalbuminuria induced by chronic endothelial activation in transgenic mice

AJP Renal Physiology ◽

10.1152/ajprenal.00558.2011 ◽

2012 ◽

Vol 302 (6) ◽

pp. F703-F712 ◽

Cited By ~ 12

Author(s):

Gangaraju Rajashekhar ◽

Akanksha Gupta ◽

Abby Marin ◽

Jessica Friedrich ◽

Antje Willuweit ◽

...

Keyword(s):

Chronic Kidney Disease ◽

Kidney Disease ◽

Cell Activation ◽

Vascular Inflammation ◽

Kidney Injury ◽

Endothelial Activation ◽

Endothelial Cell Activation ◽

Soluble Thrombomodulin ◽

Inflammatory Chemokines

Chronic kidney disease pathogenesis involves both tubular and vascular injuries. Despite abundant investigations to identify the risk factors, the involvement of chronic endothelial dysfunction in developing nephropathies is insufficiently explored. Previously, soluble thrombomodulin (sTM), a cofactor in the activation of protein C, has been shown to protect endothelial function in models of acute kidney injury. In this study, the role for sTM in treating chronic kidney disease was explored by employing a mouse model of chronic vascular activation using endothelial-specific TNF-α-expressing (tie2-TNF) mice. Analysis of kidneys from these mice after 3 mo showed no apparent phenotype, whereas 6-mo-old mice demonstrated infiltration of CD45-positive leukocytes accompanied by upregulated gene expression of inflammatory chemokines, markers of kidney injury, and albuminuria. Intervention with murine sTM with biweekly subcutaneous injections during this window of disease development between months 3 and 6 prevented the development of kidney pathology. To better understand the mechanisms of these findings, we determined whether sTM could also prevent chronic endothelial cell activation in vitro. Indeed, treatment with sTM normalized increased chemokines, adhesion molecule expression, and reduced transmigration of monocytes in continuously activated TNF-expressing endothelial cells. Our results suggest that vascular inflammation associated with vulnerable endothelium can contribute to loss in renal function as suggested by the tie2-TNF mice, a unique model for studying the role of vascular activation and inflammation in chronic kidney disease. Furthermore, the ability to restore the endothelial balance by exogenous administration of sTM via downregulation of specific adhesion molecules and chemokines suggests a potential for therapeutic intervention in kidney disease associated with chronic inflammation.

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A novel flow cytometry-based quantitative monocyte adhesion assay to estimate endothelial cell activation in vitro

BioTechniques ◽

10.2144/btn-2019-0169 ◽

2020 ◽

Vol 68 (6) ◽

pp. 325-333

Author(s):

Vinnyfred Vincent ◽

Himani Thakkar ◽

Anjali Verma ◽

Atanu Sen ◽

Nikhil Chandran ◽

...

Keyword(s):

Flow Cytometry ◽

Endothelial Cells ◽

Endothelial Cell ◽

Cell Activation ◽

Endothelial Activation ◽

Adhesion Assay ◽

Monocyte Adhesion ◽

Endothelial Cell Activation ◽

Functional Level

One of the earliest events in the development of atherosclerosis is endothelial activation, which is estimated in vitro at the functional level by quantifying monocyte adhesion. This involves the incubation of fluorescently labeled monocytes on top of cultured endothelial cells and quantifying the number of adhered monocytes. Currently, the quantification of adhered monocytes is done using microscopy or by lysing the cells and estimating the fluorescence. Here we present a novel flow cytometry-based method for the quantification of monocyte adhesion. This method could quantify the average number of monocytes adhered to a single endothelial cell after monocyte adhesion assay, and was also sensitive to the level of activation of endothelial cells. Flow cytometry-based quantification requires less time and effort compared with microscopy-based quantification.

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Endothelial cell activation by antiphospholipid antibodies is modulated by Krüppel-like transcription factors

Blood ◽

10.1182/blood-2010-10-313072 ◽

2011 ◽

Vol 117 (23) ◽

pp. 6383-6391 ◽

Cited By ~ 26

Author(s):

Kristi L. Allen ◽

Anne Hamik ◽

Mukesh K. Jain ◽

Keith R. McCrae

Keyword(s):

Endothelial Cells ◽

Antiphospholipid Antibodies ◽

Transcriptional Activity ◽

Cell Activation ◽

Critical Role ◽

Endothelial Activation ◽

Dependent Manner ◽

Endothelial Cell Activation ◽

Proinflammatory Response ◽

Endothelial Response

Abstract Antiphospholipid syndrome is characterized by thrombosis and/or recurrent pregnancy loss in the presence of antiphospholipid antibodies (APLAs). The majority of APLAs are directed against phospholipid-binding proteins, particularly β2-glycoprotein I (β2GPI). Anti-β2GPI antibodies activate endothelial cells in a β2GPI-dependent manner through a pathway that involves NF-κB. Krüppel-like factors (KLFs) play a critical role in regulating the endothelial response to inflammatory stimuli. We hypothesized that activation of endothelial cells by APLA/anti-β2GPI antibodies might be associated with decreased expression of KLFs, which in turn might facilitate cellular activation mediated through NF-κB. Our experimental results confirmed this hypothesis, demonstrating markedly decreased expression of KLF2 and KLF4 after incubation of cells with APLA/anti-β2GPI antibodies. Restoration of KLF2 or KLF4 levels inhibited NF-κB transcriptional activity and blocked APLA/anti-β2GPI–mediated endothelial activation despite NF-κB p65 phosphorylation. Chromatin immunoprecipitation analysis demonstrated that inhibition of NF-κB transcriptional activity by KLFs reflects sequestration of the cotranscriptional activator CBP/p300, making this cofactor unavailable to NF-κB. These findings suggest that the endothelial response to APLA/anti-β2GPI antibodies reflects competition between KLFs and NF-κB for their common cofactor, CBP/p300. Taken together, these observations are the first to implicate the KLFs as novel participants in the endothelial proinflammatory response to APLA/anti-β2GPI antibodies.

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