Search results for "extracellular traps"

Interleukin-9 over-expression and T helper 9 polarization in systemic sclerosis patients.

2017

Summary T helper 9 (Th9) cells and interleukin (IL)-9 are involved in the pathogenesis of several autoimmune diseases. The exact role of IL-9 and Th9 cells in patients with systemic sclerosis (SSc) have not yet been studied adequately. IL-9, IL-9R, transcription factor PU.1 (PU.1), IL-4, thymic stromal lymphopoietin (TSLP) and transforming growth factor (TGF)-β expression were assessed in skin and kidney biopsies of SSc patients and healthy controls (HC) by immunohistochemistry (IHC). The cellular source of IL-9 was also analysed by confocal microscopy analysis. Peripheral IL-9-producing cells were also studied by flow cytometry. The functional relevance of IL-9 increased expression in SSc …

Neutrophil extracellular traps arm DC vaccination against NPM-mutant myeloproliferation

2021

AbstractNeutrophil extracellular traps (NET) are web-like chromatin structures composed by dsDNA and histones, decorated with anti-microbial proteins. Their interaction with dendritic cells (DC) allows DC activation and maturation toward presentation of NET-associated antigens. Differently from other types of cell death that imply protein denaturation, NETosis preserves the proteins localized onto the DNA threads for proper enzymatic activity and conformational status, including immunogenic epitopes. Besides neutrophils, leukemic cells can release extracellular traps displaying leukemia-associated antigens, prototypically mutant nucleophosmin (NPMc+) that upon mutation translocates from nuc…

Oxidative burst and neutrophil elastase contribute to clearance of Aspergillus fumigatus pneumonia in mice.

2014

Polymorphonuclear neutrophils (PMN) are important for the control of invasive aspergillosis (IA), a major threat to immunocompromised individuals. For clearance of Aspergillus fumigatus infections, PMN employ their potent oxidative and non-oxidative mechanisms. To clarify the relative contribution of these mechanisms, we analyzed p47(phox-/-), gp91(phox-/-) and elastase (ELA) deficient mice (ELANE) after intratracheal infection with A. fumigatus. Infected p47(phox-/-) and gp91(phox-/-) mice died within 4 days and had a significant higher fungal burden in the lungs compared to wild-type controls. Interestingly, the survival of ELANE mice after infection was unimpaired suggesting that ELA is …

The Neutrophil Secretome as a Crucial Link between Inflammation and Thrombosis

2021

Cardiovascular diseases are a leading cause of death. Blood–cell interactions and endothelial dysfunction are fundamental in thrombus formation, and so further knowledge of the pathways involved in such cellular crosstalk could lead to new therapeutical approaches. Neutrophils are secretory cells that release well-known soluble inflammatory signaling mediators and other complex cellular structures whose role is not fully understood. Studies have reported that neutrophil extracellular vesicles (EVs) and neutrophil extracellular traps (NETs) contribute to thrombosis. The objective of this review is to study the role of EVs and NETs as key factors in the transition from inflammation to thrombo…

A peptide from the staphylococcal protein Efb binds P‐selectin and inhibits the interaction of platelets with leukocytes

2022

AimsP-selectin is a key surface adhesion molecule for the interaction of platelets with leukocytes. We have shown previously that the N-terminal domain of S. aureus extracellular fibrinogen-binding protein (Efb) binds to P-selectin and interferes with platelet-leukocyte aggregate formation. Here, we aimed to identify the minimal Efb motif required for binding platelets and to characterise its ability to interfering with the formation of platelet-leukocyte aggregates.Methods and ResultsUsing a library of synthetic peptides, we mapped the platelet-binding site to a continuous 20 amino acid stretch. The peptide Efb68-87 was able to bind to resting and, to a greater extent, thrombin-stimulated …

Circulating cell-free DNA: an up-coming molecular marker in exercise physiology.

2012

The phenomenon of circulating cell-free DNA (cfDNA) concentrations is of importance for many biomedical disciplines including the field of exercise physiology. Increases of cfDNA due to exercise are described to be a potential hallmark for the overtraining syndrome and might be related to, or trigger adaptations of, immune function induced by strenuous exercise. At the same time, exercise provides a practicable model for studying the phenomenon of cfDNA that is described to be of pathophysiological relevance for different topics in clinical medicine like autoimmune diseases and cancer. In this review, we are summarizing the current knowledge of exercise-based acute and chronic alterations i…

Is digital necrosis in COVID-19 caused by neutrophil extracellular traps: Potential therapeutic strategies

2021

Some of the COVID-19 patients present with ischemic lesions of their finger and toes. Standard anticoagulant therapy is usually unsuccessful for the treatment of this unique presentation of COVID-19. In this review current evidence is presented, which supports the hypothesis that these necrotic lesions are primarily related to the formation of neutrophil extracellular traps is blood vessels. Also, currently available and potential pharmaco-logical methods of the management of this unique thrombotic complication are discussed. Drugs that possibly could be used in COVID-19 patients suffering from acute ischemia of distal parts of the extremities particularly comprise DNase I and DNase1L3, whi…

Unexpected role of natural killer cell-derived interferon-γ as a driver of NETosis and DVT.

2018

A new pro-thrombotic mechanism of neutrophil extracellular traps in antiphospholipid syndrome: impact on activated protein C resistance

2021

Abstract Objectives In APS, precise evaluation of thrombotic risk is a major challenge. Different players, such as activated protein C (APC) resistance or neutrophil extracellular traps (NETs) contribute to the risk of thrombosis. Nevertheless, no study has investigated the interaction between these actors. The main objective of this study was to investigate the relation between NETs and APC resistance. Methods We designed a cross-sectional study including APS/antiphospholipid antibodies (aPL) patients and patients with autoimmune diseases (AID). We performed thrombin generation tests without and with APC to determine APC resistance. To evaluate circulating NETs, we measured plasma levels o…

Treatment of COVID-19 with MSCs: how does it work?

2021

The infusion of coronavirus disease 2019 (COVID-19) patients with mesenchymal stem cells (MSCs) potentially improves clinical symptoms, but the underlying mechanism remains unclear. We conducted a randomized, single-blind, placebo-controlled (29 patients/group) phase II clinical trial to validate previous findings and explore the potential mechanisms. Patients treated with umbilical cord-derived MSCs exhibited a shorter hospital stay (P = 0.0198) and less time required for symptoms remission (P = 0.0194) than those who received placebo. Based on chest images, both severe and critical patients treated with MSCs showed improvement by day 7 (P = 0.0099) and day 21 (P = 0.0084). MSC-treated pat…