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Cipriano A, Viviano M, Feoli A, Milite C, Sarno G, Castellano S, Sbardella G. NADPH Oxidases: From Molecular Mechanisms to Current Inhibitors. J Med Chem 2023; 66:11632-11655. [PMID: 37650225 PMCID: PMC10510401 DOI: 10.1021/acs.jmedchem.3c00770] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Indexed: 09/01/2023]
Abstract
NADPH oxidases (NOXs) form a family of electron-transporting membrane enzymes whose main function is reactive oxygen species (ROS) generation. Strong evidence suggests that ROS produced by NOX enzymes are major contributors to oxidative damage under pathologic conditions. Therefore, blocking the undesirable actions of these enzymes is a therapeutic strategy for treating various pathological disorders, such as cardiovascular diseases, inflammation, and cancer. To date, identification of selective NOX inhibitors is quite challenging, precluding a pharmacologic demonstration of NOX as therapeutic targets in vivo. The aim of this Perspective is to furnish an updated outlook about the small-molecule NOX inhibitors described over the last two decades. Structures, activities, and in vitro/in vivo specificity are discussed, as well as the main biological assays used.
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Affiliation(s)
- Alessandra Cipriano
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Monica Viviano
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Alessandra Feoli
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Ciro Milite
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Giuliana Sarno
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Sabrina Castellano
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Gianluca Sbardella
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
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Kasztelan-Szczerbinska B, Zygo B, Rycyk-Bojarzynska A, Surdacka A, Rolinski J, Cichoz-Lach H. Blood concentrations of mediators released from activated neutrophils are related to the severity of alcohol-induced liver damage. PLoS One 2023; 18:e0280068. [PMID: 36607987 PMCID: PMC9821433 DOI: 10.1371/journal.pone.0280068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 12/20/2022] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Immune dysregulation and neutrophil infiltration are hallmarks of alcohol-related liver disease (ALD). Our objective was to evaluate the blood profile of neutrophil-derived mediators [neutrophil elastase (NE), myeloperoxidase (MPO), alpha1-antitrypsin (A1AT)], and their potential relevance in ALD. METHODS 62 patients with ALD /47 males, and 15 females, aged 49,2 ± 9,9/ were prospectively recruited and distributed according to their 1/ gender, 2/ severity of liver dysfunction (by Child-Turcotte-Pugh, MELD scores, and mDF) 3/ presence of complications of ALD complications, and followed for 90 days. 24 age- and sex-matched healthy volunteers served as the control group. Neutrophil-derived biomarkers were quantified using enzyme-linked immunosorbent assays (ELISAs). RESULTS Blood concentrations of MPO and NE were significantly higher in ALD patients in comparison with controls. A1AT levels were not different. There were no gender-related differences in the studied biomarker levels. Both NE and MPO correlated with routine markers of inflammation, while NE with MELD and mDF scores. Patients with a severe ALD course i.e. MELD>20 or mDF>32, presented with significantly higher NE blood concentrations. CONCLUSIONS Our results point out the critical role of neutrophils in the pathogenesis of ALD. NE and MPO correlated with the intensity of inflammation, and NE was related to the severity of liver dysfunction.
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Affiliation(s)
| | - Bartosz Zygo
- Department of Gastroenterology with Endoscopy Unit, Independent Public Academic Hospital No. 4 in Lublin, Lublin, Poland
| | - Anna Rycyk-Bojarzynska
- Department of Gastroenterology with Endoscopy Unit, Medical University of Lublin, Lublin, Poland
| | - Agata Surdacka
- Department of Clinical Immunology, Medical University of Lublin, Lublin, Poland
| | - Jacek Rolinski
- Department of Clinical Immunology, Medical University of Lublin, Lublin, Poland
| | - Halina Cichoz-Lach
- Department of Gastroenterology with Endoscopy Unit, Medical University of Lublin, Lublin, Poland
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3
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Halliwell B. Reflections of an Aging Free Radical Part 2: Meeting Inspirational People. Antioxid Redox Signal 2022; 38:792-802. [PMID: 35651275 DOI: 10.1089/ars.2022.0070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Significance: During my long career in the field of redox biology, I met many inspiring people, especially Lester Packer. Recent Advances: This special issue of Antioxidants & Redox Signaling is dedicated to Lester Packer. Critical Issues: In this short review, I explore how Lester and other pioneers helped to develop the redox biology field and how I interacted with them. Future Directions: In our research to advance the field of redox biology, we stand on the shoulders of giants, including Lester Packer.
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Affiliation(s)
- Barry Halliwell
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University Singapore, Singapore, Singapore
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4
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Munansangu BSM, Kenyon C, Walzl G, Loxton AG, Kotze LA, du Plessis N. Immunometabolism of Myeloid-Derived Suppressor Cells: Implications for Mycobacterium tuberculosis Infection and Insights from Tumor Biology. Int J Mol Sci 2022; 23:ijms23073512. [PMID: 35408873 PMCID: PMC8998693 DOI: 10.3390/ijms23073512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 03/04/2022] [Accepted: 03/08/2022] [Indexed: 02/04/2023] Open
Abstract
The field of immunometabolism seeks to decipher the complex interplay between the immune system and the associated metabolic pathways. The role of small molecules that can target specific metabolic pathways and subsequently alter the immune landscape provides a desirable platform for new therapeutic interventions. Immunotherapeutic targeting of suppressive cell populations, such as myeloid-derived suppressor cells (MDSC), by small molecules has shown promise in pathologies such as cancer and support testing of similar host-directed therapeutic approaches in MDSC-inducing conditions such as tuberculosis (TB). MDSC exhibit a remarkable ability to suppress T-cell responses in those with TB disease. In tumors, MDSC exhibit considerable plasticity and can undergo metabolic reprogramming from glycolysis to fatty acid oxidation (FAO) and oxidative phosphorylation (OXPHOS) to facilitate their immunosuppressive functions. In this review we look at the role of MDSC during M. tb infection and how their metabolic reprogramming aids in the exacerbation of active disease and highlight the possible MDSC-targeted metabolic pathways utilized during M. tb infection, suggesting ways to manipulate these cells in search of novel insights for anti-TB therapies.
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Taylor JP, Tse HM. The role of NADPH oxidases in infectious and inflammatory diseases. Redox Biol 2021; 48:102159. [PMID: 34627721 PMCID: PMC8487856 DOI: 10.1016/j.redox.2021.102159] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 02/06/2023] Open
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOX) are enzymes that generate superoxide or hydrogen peroxide from molecular oxygen utilizing NADPH as an electron donor. There are seven enzymes in the NOX family: NOX1-5 and dual oxidase (DUOX) 1-2. NOX enzymes in humans play important roles in diverse biological functions and vary in expression from tissue to tissue. Importantly, NOX2 is involved in regulating many aspects of innate and adaptive immunity, including regulation of type I interferons, the inflammasome, phagocytosis, antigen processing and presentation, and cell signaling. DUOX1 and DUOX2 play important roles in innate immune defenses at epithelial barriers. This review discusses the role of NOX enzymes in normal physiological processes as well as in disease. NOX enzymes are important in autoimmune diseases like type 1 diabetes and have also been implicated in acute lung injury caused by infection with SARS-CoV-2. Targeting NOX enzymes directly or through scavenging free radicals may be useful therapies for autoimmunity and acute lung injury where oxidative stress contributes to pathology.
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Affiliation(s)
- Jared P Taylor
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hubert M Tse
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, USA.
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6
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Vermot A, Petit-Härtlein I, Smith SME, Fieschi F. NADPH Oxidases (NOX): An Overview from Discovery, Molecular Mechanisms to Physiology and Pathology. Antioxidants (Basel) 2021; 10:890. [PMID: 34205998 PMCID: PMC8228183 DOI: 10.3390/antiox10060890] [Citation(s) in RCA: 223] [Impact Index Per Article: 74.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/21/2021] [Accepted: 05/26/2021] [Indexed: 01/17/2023] Open
Abstract
The reactive oxygen species (ROS)-producing enzyme NADPH oxidase (NOX) was first identified in the membrane of phagocytic cells. For many years, its only known role was in immune defense, where its ROS production leads to the destruction of pathogens by the immune cells. NOX from phagocytes catalyzes, via one-electron trans-membrane transfer to molecular oxygen, the production of the superoxide anion. Over the years, six human homologs of the catalytic subunit of the phagocyte NADPH oxidase were found: NOX1, NOX3, NOX4, NOX5, DUOX1, and DUOX2. Together with the NOX2/gp91phox component present in the phagocyte NADPH oxidase assembly itself, the homologs are now referred to as the NOX family of NADPH oxidases. NOX are complex multidomain proteins with varying requirements for assembly with combinations of other proteins for activity. The recent structural insights acquired on both prokaryotic and eukaryotic NOX open new perspectives for the understanding of the molecular mechanisms inherent to NOX regulation and ROS production (superoxide or hydrogen peroxide). This new structural information will certainly inform new investigations of human disease. As specialized ROS producers, NOX enzymes participate in numerous crucial physiological processes, including host defense, the post-translational processing of proteins, cellular signaling, regulation of gene expression, and cell differentiation. These diversities of physiological context will be discussed in this review. We also discuss NOX misregulation, which can contribute to a wide range of severe pathologies, such as atherosclerosis, hypertension, diabetic nephropathy, lung fibrosis, cancer, or neurodegenerative diseases, giving this family of membrane proteins a strong therapeutic interest.
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Affiliation(s)
- Annelise Vermot
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, 38000 Grenoble, France; (A.V.); (I.P.-H.)
| | - Isabelle Petit-Härtlein
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, 38000 Grenoble, France; (A.V.); (I.P.-H.)
| | - Susan M. E. Smith
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA 30144, USA;
| | - Franck Fieschi
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, 38000 Grenoble, France; (A.V.); (I.P.-H.)
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Königstorfer A, Ashby LV, Bollar GE, Billiot CE, Gray MJ, Jakob U, Hampton MB, Winterbourn CC. Induction of the reactive chlorine-responsive transcription factor RclR in Escherichia coli following ingestion by neutrophils. Pathog Dis 2021; 79:ftaa079. [PMID: 33351093 PMCID: PMC7797021 DOI: 10.1093/femspd/ftaa079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/18/2020] [Indexed: 01/16/2023] Open
Abstract
Neutrophils generate hypochlorous acid (HOCl) and related reactive chlorine species as part of their defence against invading microorganisms. In isolation, bacteria respond to reactive chlorine species by upregulating responses that provide defence against oxidative challenge. Key questions are whether these responses are induced when bacteria are phagocytosed by neutrophils, and whether this provides them with a survival advantage. We investigated RclR, a transcriptional activator of the rclABC operon in Escherichia coli that has been shown to be specifically activated by reactive chlorine species. We first measured induction by individual reactive chlorine species, and showed that HOCl itself activates the response, as do chloramines (products of HOCl reacting with amines) provided they are cell permeable. Strong RclR activation was seen in E. coli following phagocytosis by neutrophils, beginning within 5 min and persisting for 40 min. RclR activation was suppressed by inhibitors of NOX2 and myeloperoxidase, providing strong evidence that it was due to HOCl production in the phagosome. RclR activation demonstrates that HOCl, or a derived chloramine, enters phagocytosed bacteria in sufficient amount to induce this response. Although RclR was induced in wild-type bacteria following phagocytosis, we detected no greater sensitivity to neutrophil killing of mutants lacking genes in the rclABC operon.
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Affiliation(s)
- Andreas Königstorfer
- Department of Pathology and Biomedical Science, Centre for Free Radical Research, University of Otago Christchurch, 2 Riccarton Ave, Christchurch 8011, New Zealand
| | - Louisa V Ashby
- Department of Pathology and Biomedical Science, Centre for Free Radical Research, University of Otago Christchurch, 2 Riccarton Ave, Christchurch 8011, New Zealand
| | - Gretchen E Bollar
- Department of Microbiology, School of Medicine, University of Alabama at Birmingham, 845 19th St, Birmingham AL 35294, United States
| | - Caitlin E Billiot
- Department of Microbiology, School of Medicine, University of Alabama at Birmingham, 845 19th St, Birmingham AL 35294, United States
| | - Michael J Gray
- Department of Microbiology, School of Medicine, University of Alabama at Birmingham, 845 19th St, Birmingham AL 35294, United States
| | - Ursula Jakob
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 1105 N-University, Ann Arbor MI 48109-1085, United States
| | - Mark B Hampton
- Department of Pathology and Biomedical Science, Centre for Free Radical Research, University of Otago Christchurch, 2 Riccarton Ave, Christchurch 8011, New Zealand
| | - Christine C Winterbourn
- Department of Pathology and Biomedical Science, Centre for Free Radical Research, University of Otago Christchurch, 2 Riccarton Ave, Christchurch 8011, New Zealand
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8
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Griffiths HR, Rooney MCO, Perrie Y. Does Dysregulation of Redox State Underpin the Decline of Innate Immunity with Aging? Antioxid Redox Signal 2020; 32:1014-1030. [PMID: 31989832 DOI: 10.1089/ars.2020.8021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Significance: Antibacterial defense invokes the innate immune system as a first responder, with neutrophils phagocytozing and forming neutrophil extracellular traps around pathogens in a reactive oxygen species (ROS)-dependent manner. Increased NOX2 activity and mitochondrial ROS production in phagocytic, antigen-presenting cells (APCs) affect local cytokine secretion and proteolysis of antigens for presentation to T cells at the immune synapse. Uncontrolled oxidative post-translational modifications to surface and cytoplasmic proteins in APCs during aging can impair innate immunity. Recent Advances: NOX2 plays a role in the maturation of dendritic cells, but paradoxically NOX2 activity has also been shown to promote viral pathogenicity. Accumulating evidence suggests that a reducing environment is essential to inhibit pathogen proliferation, facilitate antigenic processing in the endosomal lumen, and enable an effective immune synapse between APCs and T cells. This suggests that the kinetics and location of ROS production and reducing potential are important for effective innate immunity. Critical Issues: During aging, innate immune cells are less well able to phagocytoze, kill bacteria/viruses, and process proteins into antigenic peptides-three key steps that are necessary for developing a specific targeted response to protect against future exposure. Aberrant control of ROS production and impaired Nrf2-dependent reducing potential may contribute to age-associated immune decline. Future Directions: Local changes in redox potential may be achieved through adjuvant formulations to improve innate immunity. Further work is needed to understand the timing of delivery for redox modulators to facilitate innate immune cell recruitment, survival, antigen processing and presentation activity without disrupting essential ROS-dependent bacterial killing.
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Affiliation(s)
- Helen R Griffiths
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Matthew C O Rooney
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Yvonne Perrie
- Department of Pharmacy, University of Strathclyde, Glasgow, Scotland
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9
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Abstract
Staphylococcus aureus has become a serious threat to human health. In addition to having increased antibiotic resistance, the bacterium is a master at adapting to its host by evading almost every facet of the immune system, the so-called immune evasion proteins. Many of these immune evasion proteins target neutrophils, the most important immune cells in clearing S. aureus infections. The neutrophil attacks pathogens via a plethora of strategies. Therefore, it is no surprise that S. aureus has evolved numerous immune evasion strategies at almost every level imaginable. In this review we discuss step by step the aspects of neutrophil-mediated killing of S. aureus, such as neutrophil activation, migration to the site of infection, bacterial opsonization, phagocytosis, and subsequent neutrophil-mediated killing. After each section we discuss how S. aureus evasion molecules are able to resist the neutrophil attack of these different steps. To date, around 40 immune evasion molecules of S. aureus are known, but its repertoire is still expanding due to the discovery of new evasion proteins and the addition of new functions to already identified evasion proteins. Interestingly, because the different parts of neutrophil attack are redundant, the evasion molecules display redundant functions as well. Knowing how and with which proteins S. aureus is evading the immune system is important in understanding the pathophysiology of this pathogen. This knowledge is crucial for the development of therapeutic approaches that aim to clear staphylococcal infections.
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10
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Jasper AE, McIver WJ, Sapey E, Walton GM. Understanding the role of neutrophils in chronic inflammatory airway disease. F1000Res 2019; 8. [PMID: 31069060 PMCID: PMC6489989 DOI: 10.12688/f1000research.18411.1] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/16/2019] [Indexed: 12/28/2022] Open
Abstract
Airway neutrophilia is a common feature of many chronic inflammatory lung diseases and is associated with disease progression, often regardless of the initiating cause. Neutrophils and their products are thought to be key mediators of the inflammatory changes in the airways of patients with chronic obstructive pulmonary disease (COPD) and have been shown to cause many of the pathological features associated with disease, including emphysema and mucus hypersecretion. Patients with COPD also have high rates of bacterial colonisation and recurrent infective exacerbations, suggesting that neutrophil host defence mechanisms are impaired, a concept supported by studies showing alterations to neutrophil migration, degranulation and reactive oxygen species production in cells isolated from patients with COPD. Although the role of neutrophils is best described in COPD, many of the pathological features of this disease are not unique to COPD and also feature in other chronic inflammatory airway diseases, including asthma, cystic fibrosis, alpha-1 anti-trypsin deficiency, and bronchiectasis. There is increasing evidence for immune cell dysfunction contributing to inflammation in many of these diseases, focusing interest on the neutrophil as a key driver of pulmonary inflammation and a potential therapeutic target than spans diseases. This review discusses the evidence for neutrophilic involvement in COPD and also considers their roles in alpha-1 anti-trypsin deficiency, bronchiectasis, asthma, and cystic fibrosis. We provide an in-depth assessment of the role of the neutrophil in each of these conditions, exploring recent advances in understanding, and finally discussing the possibility of common mechanisms across diseases.
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Affiliation(s)
- Alice E Jasper
- Birmingham Acute Care Research, Institute of Inflammation and Ageing, University of Birmingham, UK, Birmingham, B15 2TT, UK
| | - William J McIver
- Birmingham Acute Care Research, Institute of Inflammation and Ageing, University of Birmingham, UK, Birmingham, B15 2TT, UK
| | - Elizabeth Sapey
- Birmingham Acute Care Research, Institute of Inflammation and Ageing, University of Birmingham, UK, Birmingham, B15 2TT, UK
| | - Georgia M Walton
- Birmingham Acute Care Research, Institute of Inflammation and Ageing, University of Birmingham, UK, Birmingham, B15 2TT, UK
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11
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Buchan KD, Prajsnar TK, Ogryzko NV, de Jong NWM, van Gent M, Kolata J, Foster SJ, van Strijp JAG, Renshaw SA. A transgenic zebrafish line for in vivo visualisation of neutrophil myeloperoxidase. PLoS One 2019; 14:e0215592. [PMID: 31002727 PMCID: PMC6474608 DOI: 10.1371/journal.pone.0215592] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 04/04/2019] [Indexed: 12/12/2022] Open
Abstract
The neutrophil enzyme myeloperoxidase (MPO) is a major enzyme made by neutrophils to generate antimicrobial and immunomodulatory compounds, notably hypochlorous acid (HOCl), amplifying their capacity for destroying pathogens and regulating inflammation. Despite its roles in innate immunity, the importance of MPO in preventing infection is unclear, as individuals with MPO deficiency are asymptomatic with the exception of an increased risk of candidiasis. Dysregulation of MPO activity is also linked with inflammatory conditions such as atherosclerosis, emphasising a need to understand the roles of the enzyme in greater detail. Consequently, new tools for investigating granular dynamics in vivo can provide useful insights into how MPO localises within neutrophils, aiding understanding of its role in preventing and exacerbating disease. The zebrafish is a powerful model for investigating the immune system in vivo, as it is genetically tractable, and optically transparent. To visualise MPO activity within zebrafish neutrophils, we created a genetic construct that expresses human MPO as a fusion protein with a C-terminal fluorescent tag, driven by the neutrophil-specific promoter lyz. After introducing the construct into the zebrafish genome by Tol2 transgenesis, we established the Tg(lyz:Hsa.MPO-mEmerald,cmlc2:EGFP)sh496 line, and confirmed transgene expression in zebrafish neutrophils. We observed localisation of MPO-mEmerald within a subcellular location resembling neutrophil granules, mirroring MPO in human neutrophils. In Spotless (mpxNL144) larvae-which express a non-functional zebrafish myeloperoxidase-the MPO-mEmerald transgene does not disrupt neutrophil migration to sites of infection or inflammation, suggesting that it is a suitable line for the study of neutrophil granule function. We present a new transgenic line that can be used to investigate neutrophil granule dynamics in vivo without disrupting neutrophil behaviour, with potential applications in studying processing and maturation of MPO during development.
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Affiliation(s)
- Kyle D. Buchan
- The Bateson Centre and Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Tomasz K. Prajsnar
- The Bateson Centre and Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Nikolay V. Ogryzko
- The Bateson Centre and Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Western Bank, Sheffield, United Kingdom
- Centre for Inflammation Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Nienke W. M. de Jong
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Michiel van Gent
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Julia Kolata
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Simon J. Foster
- Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield, United Kingdom
| | - Jos A. G. van Strijp
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Stephen A. Renshaw
- The Bateson Centre and Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Western Bank, Sheffield, United Kingdom
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12
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Butler A, Walton GM, Sapey E. Neutrophilic Inflammation in the Pathogenesis of Chronic Obstructive Pulmonary Disease. COPD 2018; 15:392-404. [DOI: 10.1080/15412555.2018.1476475] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Aidan Butler
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Georgia May Walton
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Elizabeth Sapey
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
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13
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NADPH oxidases and ROS signaling in the gastrointestinal tract. Mucosal Immunol 2018; 11:1011-1023. [PMID: 29743611 DOI: 10.1038/s41385-018-0021-8] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/15/2018] [Accepted: 02/19/2018] [Indexed: 02/04/2023]
Abstract
Reactive oxygen species (ROS), initially categorized as toxic by-products of aerobic metabolism, have often been called a double-edged sword. ROS are considered indispensable when host defense and redox signaling is concerned and a threat in inflammatory or degenerative diseases. This generalization does not take in account the diversity of oxygen metabolites being generated, their physicochemical characteristics and their production by distinct enzymes in space and time. NOX/DUOX NADPH oxidases are the only enzymes solely dedicated to ROS production and the prime ROS producer for intracellular and intercellular communication due to their widespread expression and intricate regulation. Here we discuss new insights of how NADPH oxidases act via ROS as multifaceted regulators of the intestinal barrier in homeostasis, infectious disease and intestinal inflammation. A closer look at monogenic VEOIBD and commensals as ROS source supports the view of H2O2 as key beneficial messenger in the barrier ecosystem.
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14
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Are the immunomodulatory properties of Lactobacillus rhamnosus CRL1505 peptidoglycan common for all Lactobacilli during respiratory infection in malnourished mice? PLoS One 2018. [PMID: 29518131 PMCID: PMC5843338 DOI: 10.1371/journal.pone.0194034] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Previously, we reported that Lactobacillus rhamnosus CRL1505 peptidoglycan (PG05) improves the innate immune response in immunocompromised-malnourished mice after Streptococcus pneumoniae infection. This study extends those previous findings by demonstrating that the dietary recovery of malnourished mice with nasal administration of PG05 improves not only the innate immune response but the respiratory and systemic adaptive humoral response as well. PG05 enhanced the Th2 response, the recovery of B cells, and the concentration and opsonophagocytic activity of anti-pneumococcal antibodies. In addition, by performing comparative studies with the peptidoglycans from lactobacilli of the same species (L. rhamnosus CRL534) or with similar immunomodulatory properties (L. plantarum CRL1506), we demonstrated here that PG05 has unique immunomodulatory properties that cannot be extended to peptidoglycans from other probiotic strains. However, the knowledge of the molecular characteristics of PG05 is indispensable to understand immunomodulatory abilities of L. rhamnosus CRL1505.
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15
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Nguyen GT, Green ER, Mecsas J. Neutrophils to the ROScue: Mechanisms of NADPH Oxidase Activation and Bacterial Resistance. Front Cell Infect Microbiol 2017; 7:373. [PMID: 28890882 PMCID: PMC5574878 DOI: 10.3389/fcimb.2017.00373] [Citation(s) in RCA: 424] [Impact Index Per Article: 60.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 08/02/2017] [Indexed: 12/16/2022] Open
Abstract
Reactive oxygen species (ROS) generated by NADPH oxidase play an important role in antimicrobial host defense and inflammation. Their deficiency in humans results in recurrent and severe bacterial infections, while their unregulated release leads to pathology from excessive inflammation. The release of high concentrations of ROS aids in clearance of invading bacteria. Localization of ROS release to phagosomes containing pathogens limits tissue damage. Host immune cells, like neutrophils, also known as PMNs, will release large amounts of ROS at the site of infection following the activation of surface receptors. The binding of ligands to G-protein-coupled receptors (GPCRs), toll-like receptors, and cytokine receptors can prime PMNs for a more robust response if additional signals are encountered. Meanwhile, activation of Fc and integrin directly induces high levels of ROS production. Additionally, GPCRs that bind to the bacterial-peptide analog fMLP, a neutrophil chemoattractant, can both prime cells and trigger low levels of ROS production. Engagement of these receptors initiates intracellular signaling pathways, resulting in activation of downstream effector proteins, assembly of the NADPH oxidase complex, and ultimately, the production of ROS by this complex. Within PMNs, ROS released by the NADPH oxidase complex can activate granular proteases and induce the formation of neutrophil extracellular traps (NETs). Additionally, ROS can cross the membranes of bacterial pathogens and damage their nucleic acids, proteins, and cell membranes. Consequently, in order to establish infections, bacterial pathogens employ various strategies to prevent restriction by PMN-derived ROS or downstream consequences of ROS production. Some pathogens are able to directly prevent the oxidative burst of phagocytes using secreted effector proteins or toxins that interfere with translocation of the NADPH oxidase complex or signaling pathways needed for its activation. Nonetheless, these pathogens often rely on repair and detoxifying proteins in addition to these secreted effectors and toxins in order to resist mammalian sources of ROS. This suggests that pathogens have both intrinsic and extrinsic mechanisms to avoid restriction by PMN-derived ROS. Here, we review mechanisms of oxidative burst in PMNs in response to bacterial infections, as well as the mechanisms by which bacterial pathogens thwart restriction by ROS to survive under conditions of oxidative stress.
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Affiliation(s)
- Giang T Nguyen
- Graduate Program in Immunology, Sackler School of Graduate Biomedical Sciences, Tufts UniversityBoston, MA, United States
| | - Erin R Green
- Department of Molecular Biology and Microbiology, Tufts University School of MedicineBoston, MA, United States
| | - Joan Mecsas
- Graduate Program in Immunology, Sackler School of Graduate Biomedical Sciences, Tufts UniversityBoston, MA, United States.,Department of Molecular Biology and Microbiology, Tufts University School of MedicineBoston, MA, United States
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16
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Al-Khami AA, Rodriguez PC, Ochoa AC. Energy metabolic pathways control the fate and function of myeloid immune cells. J Leukoc Biol 2017; 102:369-380. [PMID: 28515225 DOI: 10.1189/jlb.1vmr1216-535r] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 03/27/2017] [Accepted: 04/11/2017] [Indexed: 12/14/2022] Open
Abstract
The past decade has seen a significant interest in investigating the intracellular metabolism of cells of the immune system. This has increased the realization that immune cells endure metabolic reprogramming upon responding to pathogen-derived or inflammatory signals. More importantly, not only does this metabolic switch provide for the bioenergetic and biosynthetic demands but also it, in a highly specific manner, determines the cellular fate and function. In this review, we discuss the metabolic aspects that regulate the differentiation and function of myeloid cells, pivotal for both innate and adaptive immunity. The manipulation of these pathways can alter the function of these cells and therefore, could provide novel therapeutic approaches in cancer and other chronic inflammatory conditions.
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Affiliation(s)
- Amir A Al-Khami
- Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA; .,Department of Genetics, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
| | - Paulo C Rodriguez
- Augusta University, Georgia Cancer Center, Augusta, Georgia, USA; and
| | - Augusto C Ochoa
- Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA; .,Department of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
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17
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Pechous RD. With Friends Like These: The Complex Role of Neutrophils in the Progression of Severe Pneumonia. Front Cell Infect Microbiol 2017; 7:160. [PMID: 28507954 PMCID: PMC5410563 DOI: 10.3389/fcimb.2017.00160] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/12/2017] [Indexed: 01/12/2023] Open
Abstract
Pneumonia is a leading cause of death from infection in the United States and across the globe. During pulmonary infection, clear resolution of host inflammatory responses occurs in the absence of appreciable lung damage. Neutrophils are the first wave of leukocytes to arrive in the lung upon infection. After activation, neutrophils traffic from the vasculature via transendothelial migration through the lung interstitium and into the alveolar space. Successful pulmonary immunity requires neutrophil-mediated killing of invading pathogens by phagocytosis and release of a myriad of antimicrobial molecules, followed by resolution of inflammation, neutrophil apoptosis, and clearing of dead or dying neutrophils by macrophages. In addition to their antimicrobial role, it is becoming clear that neutrophils are also important modulators of innate and adaptive immune responses, primarily through the release of cytokines and recruitment of additional waves of neutrophils into the airways. Though typically essential to combating severe pneumonia, neutrophil influx into the airways is a double-edged sword: Overzealous neutrophil activation can cause severe tissue damage as a result of the release of toxic agents including proteases, cationic polypeptides, cytokines, and reactive oxygen species (ROS) aimed at killing invading microbes. In extreme cases, the damage caused by neutrophils and other innate immune mediators become the primary source of morbidity and mortality. Here, we review the complex role of neutrophils during severe pneumonia by highlighting specific molecules and processes that contribute to pulmonary immunity, but can also drive progression of severe disease. Depending on the identity of the infectious agent, enhancing or suppressing neutrophil-mediated responses may be key to effectively treating severe and typically lethal pneumonia.
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Affiliation(s)
- Roger D Pechous
- Department of Microbiology and Immunology, University of Arkansas for Medical SciencesLittle Rock, AR, USA
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18
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Foote JR, Levine AP, Behe P, Duchen MR, Segal AW. Imaging the Neutrophil Phagosome and Cytoplasm Using a Ratiometric pH Indicator. J Vis Exp 2017. [PMID: 28448042 PMCID: PMC5564471 DOI: 10.3791/55107] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Neutrophils are crucial to host innate defense and, consequently, constitute an important area of medical research. The phagosome, the intracellular compartment where the killing and digestion of engulfed particles take place, is the main arena for neutrophil pathogen killing that requires tight regulation. Phagosomal pH is one aspect that is carefully controlled, in turn regulating antimicrobial protease activity. Many fluorescent pH-sensitive dyes have been used to visualize the phagosomal environment. S-1 has several advantages over other pH-sensitive dyes, including its dual emission spectra, its resistance to photo-bleaching, and its high pKa. Using this method, we have demonstrated that the neutrophil phagosome is unusually alkaline in comparison to other phagocytes. By using different biochemical conjugations of the dye, the phagosome can be delineated from the cytoplasm so that changes in the size and shape of the phagosome can be assessed. This allows for further monitoring of ionic movement.
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Affiliation(s)
- Juliet R Foote
- Centre for Molecular Medicine, Division of Medicine, University College London
| | - Adam P Levine
- Centre for Molecular Medicine, Division of Medicine, University College London
| | - Philippe Behe
- Centre for Molecular Medicine, Division of Medicine, University College London
| | | | - Anthony W Segal
- Centre for Molecular Medicine, Division of Medicine, University College London;
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19
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Foote JR, Behe P, Frampton M, Levine AP, Segal AW. An Exploration of Charge Compensating Ion Channels across the Phagocytic Vacuole of Neutrophils. Front Pharmacol 2017; 8:94. [PMID: 28293191 PMCID: PMC5329019 DOI: 10.3389/fphar.2017.00094] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/13/2017] [Indexed: 11/13/2022] Open
Abstract
Neutrophils phagocytosing bacteria and fungi exhibit a burst of non-mitochondrial respiration that is required to kill and digest the engulfed microbes. This respiration is accomplished by the movement of electrons across the wall of the phagocytic vacuole by the neutrophil NADPH oxidase, NOX2. In this study, we have attempted to identify the non-proton ion channels or transporters involved in charge compensation by examining the effect of inhibitors on vacuolar pH and cross-sectional area, and on oxygen consumption. The chloride channel inhibitors 4-[(2-Butyl-6,7-dichloro-2-cyclopentyl-2,3-dihydro-1-oxo-1H-inden-5-yl)oxy]butanoic acid (DCPIB) and flufenamic acid (FFA) were the most effective inhibitors of alkalinisation in human neutrophil vacuoles, suggesting an efflux of chloride from the vacuole. The proton channel inhibitor, zinc (Zn2+), combined with DCPIB caused more vacuolar swelling than either compound alone, suggesting the conductance of osmotically active cations into the vacuole. Support for cation influx was provided by the broad-spectrum cation transport inhibitors anandamide and quinidine which inhibited vacuolar alkalinisation and swelling when applied with zinc. Oxygen consumption was generally unaffected by these anion or cation inhibitors alone, but when combined with Zn2+ it was dramatically reduced, suggesting that multiple channels in combination can compensate the charge. In an attempt to identify specific channels, we tested neutrophils from knock-out mouse models including CLIC1, ClC3, ClC4, ClC7, KCC3, KCNQ1, KCNE3, KCNJ15, TRPC1/3/5/6, TRPA1/TRPV1, TRPM2, and TRPV2, and double knockouts of CLIC1, ClC3, KCC3, TRPM2, and KCNQ1 with HVCN1, and humans with channelopathies involving BEST1, ClC7, CFTR, and MCOLN1. No gross abnormalities in vacuolar pH or area were found in any of these cells suggesting that we had not tested the correct channel, or that there is redundancy in the system. The respiratory burst was suppressed in the KCC3-/- and enhanced in the CLIC1-/- cells, but was normal in all others, including ClC3-/-. These results suggest charge compensation by a chloride conductance out of the vacuole and by cation/s into it. The identity of these channels remains to be established.
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Affiliation(s)
- Juliet R Foote
- Division of Medicine, Centre for Molecular Medicine, University College London London, UK
| | - Philippe Behe
- Division of Medicine, Centre for Molecular Medicine, University College London London, UK
| | - Mathew Frampton
- Division of Medicine, Centre for Molecular Medicine, University College London London, UK
| | - Adam P Levine
- Division of Medicine, Centre for Molecular Medicine, University College London London, UK
| | - Anthony W Segal
- Division of Medicine, Centre for Molecular Medicine, University College London London, UK
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20
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Neutrophils and Immunity: From Bactericidal Action to Being Conquered. J Immunol Res 2017; 2017:9671604. [PMID: 28299345 PMCID: PMC5337389 DOI: 10.1155/2017/9671604] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 01/29/2017] [Indexed: 12/19/2022] Open
Abstract
The neutrophil is the major phagocyte and the final effector cell of the innate immunity, with a primary role in the clearance of extracellular pathogens. Using the broad array of cytokines, extracellular traps, and effector molecules as the humoral arm, neutrophils play a crucial role in the host defense against pathogen infections. On the other hand, the pathogen has the capacity to overcome neutrophil-mediated host defense to establish infection causing human disease. Pathogens, such as S. aureus, have the potential to thwart neutrophil chemotaxis and phagocytosis and thereby succeed in evading killing by neutrophils. Furthermore, S. aureus surviving within neutrophils promotes neutrophil cytolysis, resulting in the release of host-derived molecules that promote local inflammation. Here, we provide a detailed overview of the mechanisms by which neutrophils kill the extracellular pathogens and how pathogens evade neutrophils degradation. This review will provide insights that might be useful for the development of novel therapies against infections caused by antibiotic resistant pathogens.
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21
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Segal AW. NADPH oxidases as electrochemical generators to produce ion fluxes and turgor in fungi, plants and humans. Open Biol 2016; 6:160028. [PMID: 27249799 PMCID: PMC4892433 DOI: 10.1098/rsob.160028] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 04/21/2016] [Indexed: 02/07/2023] Open
Abstract
The NOXs are a family of flavocytochromes whose basic structure has been largely conserved from algae to man. This is a very simple system. NADPH is generally available, in plants it is a direct product of photosynthesis, and oxygen is a largely ubiquitous electron acceptor, and the electron-transporting core of an FAD and two haems is the minimal required to pass electrons across the plasma membrane. These NOXs have been shown to be essential for diverse functions throughout the biological world and, lacking a clear mechanism of action, their effects have generally been attributed to free radical reactions. Investigation into the function of neutrophil leucocytes has demonstrated that electron transport through the prototype NOX2 is accompanied by the generation of a charge across the membrane that provides the driving force propelling protons and other ions across the plasma membrane. The contention is that the primary function of the NOXs is to supply the driving force to transport ions, the nature of which will depend upon the composition and characteristics of the local ion channels, to undertake a host of diverse functions. These include the generation of turgor in fungi and plants for the growth of filaments and invasion by appressoria in the former, and extension of pollen tubes and root hairs, and stomatal closure, in the latter. In neutrophils, they elevate the pH in the phagocytic vacuole coupled to other ion fluxes. In endothelial cells of blood vessels, they could alter luminal volume to regulate blood pressure and tissue perfusion.
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Affiliation(s)
- Anthony W Segal
- Division of Medicine, UCL, 5 University Street, London WC1E 6JJ, UK
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