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neutrophil substrate

Emmet A Francis, Volkmar Heinrich
Global bursts in free intracellular calcium (Ca2+ ) are among the most conspicuous signaling events in immune cells. To test the common view that Ca2+ bursts mediate rearrangement of the actin cytoskeleton in response to the activation of G protein-coupled receptors, we combined single-cell manipulation with fluorescence imaging and monitored the Ca2+ concentration in individual human neutrophils during complement-mediated chemotaxis. By decoupling purely chemotactic pseudopod formation from cell-substrate adhesion, we showed that physiological concentrations of anaphylatoxins, such as C5a, induced nonadherent human neutrophils to form chemotactic pseudopods but did not elicit Ca2+ bursts...
March 13, 2018: Science Signaling
J Vincent Edwards, Krystal Fontenot, Falk Liebner, Nicole Doyle Nee Pircher, Alfred D French, Brian D Condon
Nanocellulose has high specific surface area, hydration properties, and ease of derivatization to prepare protease sensors. A Human Neutrophil Elastase sensor designed with a nanocellulose aerogel transducer surface derived from cotton is compared with cotton filter paper, and nanocrystalline cellulose versions of the sensor. X-ray crystallography was employed along with Michaelis-Menten enzyme kinetics, and circular dichroism to contrast the structure/function relations of the peptide-cellulose conjugate conformation to enzyme/substrate binding and turnover rates...
March 13, 2018: International Journal of Molecular Sciences
Angelo A Manfredi, Giuseppe A Ramirez, Patrizia Rovere-Querini, Norma Maugeri
Neutrophils recognize particulate substrates of microbial or endogenous origin and react by sequestering the cargo via phagocytosis or by releasing neutrophil extracellular traps (NETs) outside the cell, thus modifying and alerting the environment and bystander leukocytes. The signals that determine the choice between phagocytosis and the generation of NETs are still poorly characterized. Neutrophils that had phagocytosed bulky particulate substrates, such as apoptotic cells and activated platelets, appear to be "poised" in an unresponsive state...
2018: Frontiers in Immunology
Graeme P Sullivan, Conor M Henry, Danielle M Clancy, Tazhir Mametnabiev, Ekaterina Belotcerkovskaya, Pavel Davidovich, Sylvia Sura-Trueba, Alexander V Garabadzhiu, Seamus J Martin
Sterile inflammation is initiated by molecules released from necrotic cells, called damage-associated molecular patterns (DAMPs). Members of the extended IL-1 cytokine family are important DAMPs, are typically only released through necrosis, and require limited proteolytic processing for activation. The IL-1 family cytokines, IL-36α, IL-36β, and IL-36γ, are expressed as inactive precursors and have been implicated as key initiators of psoriatic-type skin inflammation. We have recently found that IL-36 family cytokines are proteolytically processed and activated by the neutrophil granule-derived proteases, elastase, and cathepsin G...
March 7, 2018: Cell Death & Disease
Larissa A C Carvalho, João P P B Lopes, Gilberto H Kaihami, Railmara P Silva, Alexandre Bruni-Cardoso, Regina L Baldini, Flavia C Meotti
Uric acid is the end product of purine metabolism in humans and is an alternative physiological substrate for myeloperoxidase. Oxidation of uric acid by this enzyme generates uric acid free radical and urate hydroperoxide, a strong oxidant and potentially bactericide agent. In this study, we investigated whether the oxidation of uric acid and production of urate hydroperoxide would affect the killing activity of HL-60 cells differentiated into neutrophil-like cells (dHL-60) against a highly virulent strain (PA14) of the opportunistic pathogen Pseudomonas aeruginosa...
March 1, 2018: Redox Biology
Ghislain Opdenakker, Jo Van Damme, Jan Jeroen Vranckx
Chronic skin wounds, caused by arterial or venous insufficiency or by physical pressure, constitute an increasing medical problem as populations age. Whereas typical wounds are characterized by local inflammation that participates in the healing process, atonic wounds lack inflammatory markers, such as neutrophil infiltration, and generally do not heal. Recently, prominent roles in the immunopathology of chronic wounds were attributed to dysregulations in specific cytokines, chemokines, matrix metalloproteinases (MMPs), and their substrates...
February 27, 2018: Trends in Immunology
Cedric Delporte, Karim Zouaoui Boudjeltia, Paul G Furtmueller, Richard A Maki, Marc Dieu, Caroline Noyon, Monika Soudi, Damien Dufour, Catherine Coremans, Vincent Nuyens, Florence Reye, Alexandre Rousseau, Martine Raes, Nicole Moguilevsky, Michel Vanhaeverbeek, Jean Ducobu, Jean Neve, Bernard Robaye, Luc Vanhamme, Wanda F Reynolds, Christian Obinger, Pierre Van Antwerpen
Protein carbamylation by cyanate is a post-translational modification associated with several (patho)physiological conditions, including cardiovascular disorders. However, the biochemical pathways leading to protein carbamylation are incompletely characterized. This work demonstrates that the heme protein myeloperoxidase, which is secreted at high concentrations at inflammatory sites from stimulated neutrophils and monocytes, is able to catalyze the two-electron oxidation of cyanide to cyanate and promote the carbamylation of taurine, lysine and low-density-lipoproteins...
March 1, 2018: Journal of Biological Chemistry
Manoj K Pandey, Gregory A Grabowski, Jörg Köhl
The complement system is well appreciated for its role as an important effector of innate immunity that is activated by the classical, lectin or alternative pathway. C5a is one important mediator of the system that is generated in response to canonical and non-canonical C5 cleavage by circulating or cell-derived proteases. In addition to its function as a chemoattractant for neutrophils and other myeloid effectors, C5a and its sister molecule C3a have concerted roles in cell homeostasis and surveillance. Through activation of their cognate G protein coupled receptors, C3a and C5a regulate multiple intracellular pathways within the mitochondria and the lysosomal compartments that harbor multiple enzymes critical for protein, carbohydrate and lipid metabolism...
February 22, 2018: Seminars in Immunology
Javier Pascual, Bärbel U Foesel, Alicia Geppert, Katharina J Huber, Christian Boedeker, Manja Luckner, Gerhard Wanner, Jörg Overmann
A novel slow-growing bacterium, designated strain AW1220T , was isolated from agricultural floodplain soil sampled at Mashare (Kavango region, Namibia) by using a high-throughput cultivation approach. Strain AW1220T was characterized as a Gram-negative, non-motile, rod-shaped bacterium. Occasionally, some cells attained an unusual length of up to 35 µm. The strain showed positive responses for catalase and cytochrome-c oxidase and divided by binary fission and/or budding. The strain had an aerobic chemoorganoheterotrophic metabolism and was also able to grow under micro-oxic conditions...
February 14, 2018: International Journal of Systematic and Evolutionary Microbiology
Fatma H Al-Awadhi, Valerie J Paul, Hendrik Luesch
Three new 3-amino-6-hydroxy-2-piperidone (Ahp)-containing cyclic depsipeptides named loggerpeptins A-C (1-3) along with molassamide (4) were discovered from a marine cyanobacterium, extending the structural diversity of this prevalent scaffold of cyanobacterial serine protease inhibitors. Molassamide (4), containing the 2-amino-butenoic (Abu) unit in the cyclic core, was the most potent and selective analogue against human neutrophil elastase (HNE). Given the growing evidence supporting the role of HNE in breast cancer progression and metastasis, we assessed the cellular effects of compounds 3 and 4 in the context of targeting invasive breast cancer...
February 5, 2018: Chembiochem: a European Journal of Chemical Biology
Nienke W M de Jong, Nicoleta T Ploscariu, Kasra X Ramyar, Brandon L Garcia, Alvaro I Herrera, Om Prakash, Benjamin B Katz, Kevin G Leidal, William Nauseef, Kok van Kessel, Jos van Strijp, Brian V Geisbrecht
The heme-containing enzyme myeloperoxidase (MPO) is critical for optimal antimicrobial activity of human neutrophils. We recently discovered that the bacterium Staphylococcus aureus expresses a novel immune evasion protein, called SPIN, that binds tightly to MPO, inhibits MPO activity, and contributes to bacterial survival following phagocytosis. A co-crystal structure of SPIN bound to MPO suggested that SPIN blocks substrate access to the catalytic heme by inserting an N-terminal β-hairpin into the MPO active site channel...
January 5, 2018: Journal of Biological Chemistry
Patrick A Eyers
The addition of phosphate groups to substrates allows protein kinases to regulate a myriad of biological processes, and contextual analysis of protein-bound phosphate is important for understanding how kinases contribute to physiology and disease. Leucine-rich repeat kinase 2 (LRRK2) is a Ser/Thr kinase linked to familial and sporadic cases of Parkinson's disease (PD). Recent work established that multiple Rab GTPases are physiological substrates of LRRK2, with Rab10 in particular emerging as a human substrate whose site-specific phosphorylation mirrors hyperactive LRRK2 lesions associated with PD...
January 5, 2018: Biochemical Journal
Nicholas J Laping, Michael P DeMartino, Joshua E Cottom, Jeffrey M Axten, John G Emery, Jeffrey H Guss, Miriam Burman, James J Foley, Mui Cheung, Allen Oliff, Sanjay Kumar
Neutropenia is a common consequence of radiation and chemotherapy in cancer patients. The resulting immunocompromised patients become highly susceptible to potentially life-threatening infections. Granulocyte colony-stimulating factor (G-CSF) is known to stimulate neutrophil production and is widely used as a treatment of chemotherapy-induced neutropenia. A small-molecule G-CSF secretagogue without a requirement for refrigerated supply chain would offer a more convenient and cost-effective treatment of chemotherapy-induced neutropenia...
December 12, 2017: Blood Advances
Louisa V Forbes, Anthony J Kettle
Myeloperoxidase, an abundant neutrophil enzyme, promotes oxidative damage during inflammation by generating hypohalous acids and free radicals. Currently, there are no selective drugs to inhibit its adverse activity. This short-coming is partly due to the lack of screening assays that mimic the complex enzymatic activities of myeloperoxidase in vivo. We have developed an assay for myeloperoxidase activity that includes its major physiological substrates - chloride, thiocyanate, tyrosine, and urate. The multi-substrate assay monitors bleaching of 5-thio-2-nitrobenzoic acid and measures total oxidant production when hydrogen peroxide activates the enzyme...
December 16, 2017: Analytical Biochemistry
Sidnei C Santos, Martin G Liebensteiner, Antonie H van Gelder, Mauricio R Dimitrov, Paulo F Almeida, Cristina M Quintella, Alfons J M Stams, Irene Sánchez-Andrea
Glycerol is a main co-product of biodiesel production. Crude glycerol may serve as a cheap and attractive substrate in biotechnological applications, e.g. for the production of valuable chemicals or as an electron donor for reduction processes. In this work, sulfate reduction with glycerol was studied at neutral and acidic pH using bioreactor sludge samples and Tinto River sediments as a source of inoculum, respectively. Communities of sulfate-reducing bacteria (SRB) and fermentative bacteria were co-enriched at both pH values...
November 29, 2017: Journal of General and Applied Microbiology
Hye-Kyung Lee, Il-Doo Kim, Hahnbie Lee, Lidan Luo, Seung-Woo Kim, Ja-Kyeong Lee
It has been reported that the innate immune response plays important roles in brain ischemia and that the infiltration of blood-derived immune cells is a key initiator of this response. Nerve injury-induced protein 1 (Ninjurin 1, Ninj1) is a cell adhesion molecule responsible for cell-to-cell interactions between immune cells and endothelial cells. In the present study, we investigated the proinflammatory and neuroprotective effects of Ninj1 and a dodecamer peptide harboring Ninj1 N-terminal adhesion motif (N-NAM, Pro26~Asn37) in a rat middle cerebral artery occlusion (MCAO) model of stroke...
November 14, 2017: Molecular Neurobiology
David Muñoz, Maria K Serrano, Maria E Hernandez, Ross Haller, Tamara Swanson, Joel W Slaton, Akhouri A Sinha, Michael J Wilson
Proteinases secreted by the prostate gland have a reproductive function in cleaving proteins in the ejaculate and in the female reproductive tract, but some may have a fundamental role in disease and pathological processes including cancer. The purpose of this study was to determine if there were differences in proteinase activities in urine samples collected following prostate massage of men positive (CaP) or negative (no evidence of malignancy, NEM) for biopsy determined prostate cancer. Matrix metalloproteinase (MMP) and serine proteinase activities were detected using protein substrate zymography...
December 2017: Experimental and Molecular Pathology
Federica Fusella, Laura Seclì, Elena Busso, Anna Krepelova, Enrico Moiso, Stefania Rocca, Laura Conti, Laura Annaratone, Cristina Rubinetto, Maurizia Mello-Grand, Vijay Singh, Giovanna Chiorino, Lorenzo Silengo, Fiorella Altruda, Emilia Turco, Alessandro Morotti, Salvatore Oliviero, Isabella Castellano, Federica Cavallo, Paolo Provero, Guido Tarone, Mara Brancaccio
NF-κB is a transcription factor involved in the regulation of multiple physiological and pathological cellular processes, including inflammation, cell survival, proliferation, and cancer cell metastasis. NF-κB is frequently hyperactivated in several cancers, including triple-negative breast cancer. Here we show that NF-κB activation in breast cancer cells depends on the presence of the CHORDC1 gene product Morgana, a previously unknown component of the IKK complex and essential for IκBα substrate recognition...
November 21, 2017: Nature Communications
Jingjing Wang, Yi Chu, Xiaoying Zhou
BACKGROUD: Dipeptidyl peptidase I (DPPI), a lysosomal cysteine protease is derived from granule immune cells including mast cell, neutrophils, and toxicity T cells. DPPI can activate serine proteases by removal of dipeptides from N-termini of the pro-proteases, resulting in granule immune cells activation which involved in physiological or pathological responses. Triperygium Wilfordii Polyglucoside (TWP) is one of the traditional Chinese medicines, and commonly used in rheumatoid arthritis (RA) treatment...
October 11, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
Krystal R Fontenot, J Vincent Edwards, David Haldane, Nicole Pircher, Falk Liebner, Brian D Condon, Huzaifah Qureshi, Dorne Yager
Interfacing nanocellulosic-based biosensors with chronic wound dressings for protease point of care diagnostics combines functional material properties of high specific surface area, appropriate surface charge, and hydrophilicity with biocompatibility to the wound environment. Combining a protease sensor with a dressing is consistent with the concept of an intelligent dressing, which has been a goal of wound-dressing design for more than a quarter century. We present here biosensors with a nanocellulosic transducer surface (nanocrystals, nanocellulose composites, and nanocellulosic aerogels) immobilized with a fluorescent elastase tripeptide or tetrapeptide biomolecule, which has selectivity and affinity for human neutrophil elastase present in chronic wound fluid...
January 1, 2017: Journal of Biomaterials Applications
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