scholarly journals A fluorogenic peptide-based smartprobe for the detection of neutrophil extracellular traps and inflammation

2021 ◽  
Vol 57 (1) ◽  
pp. 97-100
Author(s):  
Maria R. Rios ◽  
Gloria Garoffolo ◽  
Giulia Rinaldi ◽  
Alicia Megia-Fernandez ◽  
Silvia Ferrari ◽  
...  
Keyword(s):  
Neutrophil Elastase ◽  
Human Neutrophil ◽  
Neutrophil Extracellular Traps ◽  
Human Neutrophil Elastase ◽  
Extracellular Traps ◽  
Fluorogenic Probe ◽  
Activated Neutrophils ◽  
Fluorogenic Peptide

A highly specific, fluorogenic probe detects human neutrophil elastase (hNE) in activated neutrophils and Neutrophil Extracellular Traps (NETs).

Neutrophil Extracellular Traps (NETs) in Patients with Congenital Neutropenia

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 15-15
Author(s):  
Christine Happle ◽  
Manuela Germeshausen ◽  
Cornelia Zeidler ◽  
Karl Welte ◽  
Julia Skokowa
Keyword(s):  
Peripheral Blood ◽  
Neutrophil Elastase ◽  
Myeloid Cells ◽  
Neutrophil Extracellular Traps ◽  
Extracellular Dna ◽  
Lower Amount ◽  
Congenital Neutropenia ◽  
Aberrant Expression ◽  
Extracellular Traps ◽  
Activated Neutrophils

Abstract Abstract 15 Activated neutrophils kill microbes by phagocytosis and extracellular mechanisms, including neutrophil extracellular traps (NETs), which are composed of decondensed chromatin and granular proteins such as neutrophil elastase (NE) and cathepsin G. Enzymatic generation of reactive oxygen species (ROS) by NADPH oxidase and the release of serine proteases such as NE have been shown to be essential factors for NET formation. Patients with chronic granulmatous disease (CGD), who lack a normal generation of ROS, show a defective NET formation. Since myeloid cells of patients with severe congenital neutropenia (CN) show an aberrant expression pattern of granular proteases such as neutrophil elastase (NE) or myeloperoxidase, we aimed to analyse NET formation in activated neutrophils of these patients. CN is a heterogeneous hematological disorder, characterized by peripheral blood neutrophil counts below 0,2×109/l and a maturation arrest of myelopoiesis at the promyelocytic/myelocytic stage. 60% of CN patients harbor autosomal dominant mutations within the ELA2 gene encoding for NE, but also mutations in other genes (e.g. HAX1, G6PC3, WAS, GFI1, p14) have been found to be disease-causing. Previously, we described severely diminished levels of NE in myeloid cells of CN patients. Here, we aimed to explore NET formation in neutrophils of CN patients. Moreover, we intended to analyze the effects of a reduced ELA2 expression and gene mutations as seen in CN patients on NET formation in vitro. Granulocytes of CN patients undergoing G-CSF therapy were extracted by density centrifugation, stimulated with phorbol myristate acetate (PMA, 50 nM, up to 240 min) and then tested for NET formation. NETs were stained with an extracellular DNA dye or DAPI. Our analyses showed normal NET formation in peripheral blood granulocytes of two patients with HAX1-related neutropenia, whereas there was a significantly lower amount of NETs in two patients with ELA2 mutations. One further patient out of three CN patients with unknown mutations showed a reduced amount of NETs in bone marrow PMNs. To further evaluate the possible effect of downregulated ELA2 expression on NET formation, we transduced primary human CD34+ cells with a lentiviral-based shRNA construct downregulating the expression of NE. Subsequently, these cells were differentiated into granulocytes with a cytokine cocktail containing G-CSF and tested for their ability to form NETs. We found an almost completely abolished NET formation in cells transduced with ELA2 shRNA as compared to control cells. Hitherto, CGD is the only immunodeficiency with a clearly defective NET formation. Our results point to an impaired formation of NETs also in CN patients carrying ELA2 mutations. This supports the recent finding of a central role for NE in NET formation. Two patients with HAX1 related CN showed a normal ability to form NETs. Our further work will aim to better define the subgroup of CN patients defective in NET formation. Disclosures: No relevant conflicts of interest to declare.

Human neutrophil elastase inhibitory activity of Solanum dulcamara extracts

2006 ◽  
Vol 27 (S 1) ◽  
Author(s):  
K Jenett-Siems ◽  
U Friedrich ◽  
MF Melzig
Keyword(s):  
Inhibitory Activity ◽  
Neutrophil Elastase ◽  
Human Neutrophil ◽  
Human Neutrophil Elastase ◽  
Solanum Dulcamara

scholarly journals Neutrophil elastase and myeloperoxidase regulate the formation of neutrophil extracellular traps

2010 ◽  
Vol 191 (3) ◽  
pp. 677-691 ◽  
Author(s):  
Venizelos Papayannopoulos ◽  
Kathleen D. Metzler ◽  
Abdul Hakkim ◽  
Arturo Zychlinsky
Keyword(s):  
Immune Deficiency ◽  
Neutrophil Elastase ◽  
Serine Proteases ◽  
Neutrophil Extracellular Traps ◽  
Oxygen Species ◽  
Chromatin Decondensation ◽  
Unknown Mechanism ◽  
Extracellular Traps ◽  
Decondensed Chromatin ◽  
Chromatin Density

Neutrophils release decondensed chromatin termed neutrophil extracellular traps (NETs) to trap and kill pathogens extracellularly. Reactive oxygen species are required to initiate NET formation but the downstream molecular mechanism is unknown. We show that upon activation, neutrophil elastase (NE) escapes from azurophilic granules and translocates to the nucleus, where it partially degrades specific histones, promoting chromatin decondensation. Subsequently, myeloperoxidase synergizes with NE in driving chromatin decondensation independent of its enzymatic activity. Accordingly, NE knockout mice do not form NETs in a pulmonary model of Klebsiella pneumoniae infection, which suggests that this defect may contribute to the immune deficiency of these mice. This mechanism provides for a novel function for serine proteases and highly charged granular proteins in the regulation of chromatin density, and reveals that the oxidative burst induces a selective release of granular proteins into the cytoplasm through an unknown mechanism.

scholarly journals Silver Nanoparticles Induce Neutrophil Extracellular Traps Via Activation of PAD and Neutrophil Elastase

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 317
Author(s):  
HanGoo Kang ◽  
Jinwon Seo ◽  
Eun-Jeong Yang ◽  
In-Hong Choi
Keyword(s):  
Silver Nanoparticles ◽  
Neutrophil Elastase ◽  
Mammalian Cells ◽  
Antimicrobial Properties ◽  
Neutrophil Extracellular Traps ◽  
Arginine Deiminase ◽  
Human Neutrophils ◽  
Extracellular Traps ◽  
Peptidyl Arginine Deiminase ◽  
Key Factor

Silver nanoparticles (AgNPs) are widely used in various fields because of their antimicrobial properties. However, many studies have reported that AgNPs can be harmful to both microorganisms and humans. Reactive oxygen species (ROS) are a key factor of cytotoxicity of AgNPs in mammalian cells and an important factor in the immune reaction of neutrophils. The immune reactions of neutrophils include the expulsion of webs of DNA surrounded by histones and granular proteins. These webs of DNA are termed neutrophil extracellular traps (NETs). NETs allow neutrophils to catch and destroy pathogens in extracellular spaces. In this study, we investigated how AgNPs stimulate neutrophils, specifically focusing on NETs. Freshly isolated human neutrophils were treated with 5 or 100 nm AgNPs. The 5 nm AgNPs induced NET formation, but the 100 nm AgNPs did not. Subsequently, we investigated the mechanism of AgNP-induced NETs using known inhibitors related to NET formation. AgNP-induced NETs were dependent on ROS, peptidyl arginine deiminase, and neutrophil elastase. The result in this study indicates that treatment of 5 nm AgNPs induce NET formation through histone citrullination by peptidyl arginine deiminase and histone cleavage by neutrophil elastase.

scholarly journals Flavonoids as inhibitors of human neutrophil elastase

2021 ◽  
Vol 36 (1) ◽  
pp. 1016-1028
Author(s):  
Katarzyna Jakimiuk ◽  
Jakub Gesek ◽  
Atanas G. Atanasov ◽  
Michał Tomczyk
Keyword(s):  
Neutrophil Elastase ◽  
Human Neutrophil ◽  
Human Neutrophil Elastase

Inhibition of Human Neutrophil Elastase with Peptidyl Electrophilic Ketones. 2. Orally Active PG-Val-Pro-Val Pentafluoroethyl Ketones

1994 ◽  
Vol 37 (26) ◽  
pp. 4538-4553 ◽  
Author(s):  
Michael R. Angelastro ◽  
Larry E. Baugh ◽  
Philippe Bey ◽  
Joseph P. Burkhart ◽  
Teng-Man Chen ◽  
...  
Keyword(s):  
Neutrophil Elastase ◽  
Human Neutrophil ◽  
Human Neutrophil Elastase ◽  
Orally Active

scholarly journals An Improved Strategy to Recover Large Fragments of Functional Human Neutrophil Extracellular Traps

2013 ◽  
Vol 4 ◽  
Author(s):  
Lorena Barrientos ◽  
Viviana Marin-Esteban ◽  
Luc de Chaisemartin ◽  
Vanessa Lievin Le-Moal ◽  
Catherine Sandré ◽  
...  
Keyword(s):  
Human Neutrophil ◽  
Neutrophil Extracellular Traps ◽  
Extracellular Traps

Optimisation of a human neutrophil elastase assay and investigation of the effect of sesquiterpene lactones

Biologicals ◽  
2005 ◽  
Vol 33 (3) ◽  
pp. 175-184 ◽  
Author(s):  
Karin Schorr ◽  
Anita Rott ◽  
FernandoBatista Da Costa ◽  
Irmgard Merfort
Keyword(s):  
Neutrophil Elastase ◽  
Human Neutrophil ◽  
Sesquiterpene Lactones ◽  
Human Neutrophil Elastase
Sign in / Sign up

Export Citation Format

Share Document