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Chen Y, Markov N, Gigon L, Hosseini A, Yousefi S, Stojkov D, Simon HU. The BK Channel Limits the Pro-Inflammatory Activity of Macrophages. Cells 2024; 13:322. [PMID: 38391935 PMCID: PMC10886595 DOI: 10.3390/cells13040322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 01/31/2024] [Accepted: 02/07/2024] [Indexed: 02/24/2024] Open
Abstract
Macrophages play a crucial role in the innate immune response, serving as key effector cells in the defense against pathogens. Although the role of the large-conductance voltage and calcium-activated potassium channel, also known as the KCa1.1 or BK channel, in regulating neurotransmitter release and smooth muscle contraction is well known, its potential involvement in immune regulation remains unclear. We employed BK-knockout macrophages and noted that the absence of a BK channel promotes the polarization of macrophages towards a pro-inflammatory phenotype known as M1 macrophages. Specifically, the absence of the BK channel resulted in a significant increase in the secretion of the pro-inflammatory cytokine IL-6 and enhanced the activity of extracellular signal-regulated kinases 1 and 2 (Erk1/2 kinases), Ca2+/calmodulin-dependent protein kinase II (CaMKII), and the transcription factor ATF-1 within M1 macrophages. Additionally, the lack of the BK channel promoted the activation of the AIM2 inflammasome without affecting the activation of the NLRC4 and NLRP3 inflammasomes. To further investigate the role of the BK channel in regulating AIM2 inflammasome activation, we utilized BK channel inhibitors, such as paxilline and iberiotoxin, along with the BK channel activator NS-11021. Pharmacological inactivation of the BK channel increased, and its stimulation inhibited IL-1β production following AIM2 inflammasome activation in wild-type macrophages. Moreover, wild-type macrophages displayed increased calcium influx when activated with the AIM2 inflammasome, whereas BK-knockout macrophages did not due to the impaired extracellular calcium influx upon activation. Furthermore, under conditions of a calcium-free medium, IL-1β production following AIM2 inflammasome activation was increased in both wild-type and BK-knockout macrophages. This suggests that the BK channel is required for the influx of extracellular calcium in macrophages, thus limiting AIM2 inflammasome activation. In summary, our study reveals a regulatory role of the BK channel in macrophages under inflammatory conditions.
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Affiliation(s)
- Yihe Chen
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Nikita Markov
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Lea Gigon
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Aref Hosseini
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
- Institute of Biochemistry, Brandenburg Medical School, 16816 Neuruppin, Germany
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2
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Hosseini A, Germic N, Markov N, Stojkov D, Oberson K, Yousefi S, Simon HU. The regulatory role of eosinophils in adipose tissue depends on autophagy. Front Immunol 2024; 14:1331151. [PMID: 38235134 PMCID: PMC10792036 DOI: 10.3389/fimmu.2023.1331151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/06/2023] [Indexed: 01/19/2024] Open
Abstract
Introduction Obesity is a metabolic condition that elevates the risk of all-cause mortality. Brown and beige adipose tissues, known for their thermogenic properties, offer potential therapeutic targets for combating obesity. Recent reports highlight the role of immune cells, including eosinophils, in adipose tissue homeostasis, while the underlying mechanisms are poorly understood. Methods To study the role of autophagy in eosinophils in this process, we used a genetic mouse model lacking autophagy-associated protein 5 (Atg5), specifically within the eosinophil lineage (Atg5 eoΔ). Results The absence of Atg5 in eosinophils led to increased body weight, impaired glucose metabolism, and alterations in the cellular architecture of adipose tissue. Our findings indicate that Atg5 modulates the functional activity of eosinophils within adipose tissue rather than their abundance. Moreover, RNA-seq analysis revealed upregulation of arginase 2 (Arg2) in Atg5-knockout eosinophils. Increased Arg2 activity was shown to suppress adipocyte beiging. Furthermore, we observed enrichment of the purine pathway in the absence of Atg5 in eosinophils, leading to a pro-inflammatory shift in macrophages and a further reduction in beiging. Discussion The data shed light on the importance of autophagy in eosinophils and its impact on adipose tissue homeostasis by suppressing Arg2 expression and limiting inflammation in adipose tissue.
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Affiliation(s)
- Aref Hosseini
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Nina Germic
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Nikita Markov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Kevin Oberson
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
- Institute of Biochemistry, Brandenburg Medical School, Neuruppin, Germany
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3
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Stojkov D, Yousefi S, Simon HU. NETs: Important players in asthma? J Allergy Clin Immunol 2024; 153:100-102. [PMID: 37802473 DOI: 10.1016/j.jaci.2023.09.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 09/27/2023] [Accepted: 09/29/2023] [Indexed: 10/10/2023]
Affiliation(s)
- Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland; Institute of Biochemistry, Brandenburg Medical School, Neuruppin, Germany.
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Gigon L, Fettrelet T, Miholic M, McLeish KR, Yousefi S, Stojkov D, Simon HU. Syntaxin-4 and SNAP23 are involved in neutrophil degranulation, but not in the release of mitochondrial DNA during NET formation. Front Immunol 2023; 14:1272699. [PMID: 37885878 PMCID: PMC10599146 DOI: 10.3389/fimmu.2023.1272699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 09/26/2023] [Indexed: 10/28/2023] Open
Abstract
Neutrophils are a specialized subset of white blood cells, which have the ability to store pre-formed mediators in their cytoplasmic granules. Neutrophils are well-known effector cells involved in host protection against pathogens through diverse mechanisms such as phagocytosis, degranulation, extracellular traps, and oxidative burst. In this study, we provide evidence highlighting the significance of the SNARE proteins syntaxin-4 and synaptosomal-associated protein (SNAP) 23 in the release of azurophilic granules, specific granules, and the production of reactive oxygen species in human neutrophils. In contrast, the specific blockade of either syntaxin-4 or SNAP23 did not prevent the release of mitochondrial dsDNA in the process of neutrophil extracellular trap (NET) formation. These findings imply that degranulation and the release of mitochondrial dsDNA involve at least partially distinct molecular pathways in neutrophils.
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Affiliation(s)
- Lea Gigon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | | | - Marta Miholic
- Institute of Pharmacology, University of Bern, Bern, Switzerland
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
| | - Kenneth R. McLeish
- Department of Medicine, University of Louisville School of Medicine, Louisville, KY, United States
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
- Institute of Biochemistry, Brandenburg Medical School, Neuruppin, Germany
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5
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Stojkov D, Claus MJ, Kozlowski E, Oberson K, Schären OP, Benarafa C, Yousefi S, Simon HU. NET formation is independent of gasdermin D and pyroptotic cell death. Sci Signal 2023; 16:eabm0517. [PMID: 36693132 DOI: 10.1126/scisignal.abm0517] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Neutrophil extracellular traps (NETs) are DNA scaffolds coated with granule proteins that are released by neutrophils to ensnare and kill bacteria. NET formation occurs in response to many stimuli through independent molecular pathways. Although NET release has been equated to a form of lytic cell death, live neutrophils can rapidly release antimicrobial NETs. Gasdermin D (GSDMD), which causes pyroptotic death in macrophages, is thought to be required for NET formation by neutrophils. Through experiments with known physiological activators of NET formation and ligands that activate canonical and noncanonical inflammasome signaling pathways, we demonstrated that Gsdmd-deficient mouse neutrophils were as competent as wild-type mouse neutrophils in producing NETs. Furthermore, GSDMD was not cleaved in wild-type neutrophils during NET release in response to inflammatory mediators. We found that activation of both canonical and noncanonical inflammasome signaling pathways resulted in GSDMD cleavage in wild-type neutrophils but was not associated with cell death. Moreover, NET formation as a result of either pathway of inflammasome activation did not require GSDMD. Together, these data suggest that NETs can be formed by viable neutrophils after inflammasome activation and that this function does not require GSDMD.
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Affiliation(s)
- Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Meike J Claus
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | | | - Kevin Oberson
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Olivier P Schären
- Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Charaf Benarafa
- Institute of Virology and Immunology, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland.,Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia.,Laboratory of Molecular Immunology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia.,Institute of Biochemistry, Medical School Brandenburg, Neuruppin, Germany
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6
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Abstract
Neutrophils are the most abundant innate immune cells in human blood, emerging as important players in a variety of diseases. Mitochondria are bioenergetic, biosynthetic, and signaling organelles critical for cell fate and function. Mitochondria have been overlooked in neutrophil research owing to the conventional view that neutrophils contain few, if any, competent mitochondria and do not rely on these organelles for adenosine triphosphate production. A growing body of evidence suggests that mitochondria participate in neutrophil biology at many levels, ranging from neutrophil development to chemotaxis, effector function, and cell death. Moreover, mitochondria and mitochondrial components, such as mitochondrial deoxyribonucleic acid, can be released by neutrophils to eliminate infection and/or shape immune response, depending on the specific context. In this review, we provide an update on the functional role of mitochondria in neutrophils, highlight mitochondria as key players in modulating the neutrophil phenotype and function during infection and inflammation, and discuss the possibilities and challenges to exploit the unique aspects of mitochondria in neutrophils for disease treatment.
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Affiliation(s)
- Shuang Peng
- Institute of Pharmacology University of Bern Bern Switzerland
| | - Jian Gao
- Department of Molecular and Cellular Oncology The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Darko Stojkov
- Institute of Pharmacology University of Bern Bern Switzerland
| | - Shida Yousefi
- Institute of Pharmacology University of Bern Bern Switzerland
| | - Hans‐Uwe Simon
- Institute of Pharmacology University of Bern Bern Switzerland
- Department of Clinical Immunology and Allergology Sechenov University Moscow Russia
- Laboratory of Molecular Immunology, Institute of Fundamental Medicine and Biology Kazan Federal University Kazan Russia
- Institute of Biochemistry, Brandenburg Medical School Neuruppin Germany
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7
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Peng S, Stojkov D, Gao J, Oberson K, Latzin P, Casaulta C, Yousefi S, Simon HU. Nascent RHOH acts as a molecular brake on actomyosin-mediated effector functions of inflammatory neutrophils. PLoS Biol 2022; 20:e3001794. [PMID: 36108062 PMCID: PMC9514642 DOI: 10.1371/journal.pbio.3001794] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 09/27/2022] [Accepted: 08/11/2022] [Indexed: 12/22/2022] Open
Abstract
In contrast to molecular changes associated with increased inflammatory responses, little is known about intracellular counter-regulatory mechanisms that control signaling cascades associated with functional responses of neutrophils. Active RHO GTPases are typically considered as effector proteins that elicit cellular responses. Strikingly, we show here that RHOH, although being constitutively GTP-bound, limits neutrophil degranulation and the formation of neutrophil extracellular traps (NETs). Mechanistically, RHOH is induced under inflammatory conditions and binds to non-muscle myosin heavy chain IIA (NMHC IIA) in activated neutrophils in order to inhibit the transport of mitochondria and granules along actin filaments, which is partially reverted upon disruption of the interaction with NMHC IIA by introducing a mutation in RhoH at lysine 34 (RhoHK34A). In parallel, RHOH inhibits actin polymerization presumably by modulating RAC1 activity. In vivo studies using Rhoh-/- mice, demonstrate an increased antibacterial defense capability against Escherichia coli (E. coli). Collectively, our data reveal a previously undefined role of RHOH as a molecular brake for actomyosin-mediated neutrophil effector functions, which represents an intracellular regulatory axis involved in controlling the strength of an antibacterial inflammatory response.
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Affiliation(s)
- Shuang Peng
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Jian Gao
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing, China
| | - Kevin Oberson
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Philipp Latzin
- Division of Respiratory Medicine, Department of Pediatrics, University Children’s Hospital of Bern, University of Bern, Bern, Switzerland
| | - Carmen Casaulta
- Division of Respiratory Medicine, Department of Pediatrics, University Children’s Hospital of Bern, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
- Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia
- Laboratory of Molecular Immunology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
- Institute of Biochemistry, Brandenburg Medical School, Neuruppin, Germany
- * E-mail:
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8
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Stojkov D, Gigon L, Peng S, Lukowski R, Ruth P, Karaulov A, Rizvanov A, Barlev NA, Yousefi S, Simon HU. Physiological and Pathophysiological Roles of Metabolic Pathways for NET Formation and Other Neutrophil Functions. Front Immunol 2022; 13:826515. [PMID: 35251008 PMCID: PMC8889909 DOI: 10.3389/fimmu.2022.826515] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/20/2022] [Indexed: 12/12/2022] Open
Abstract
Neutrophils are the most numerous cells in the leukocyte population and essential for innate immunity. To limit their effector functions, neutrophils are able to modulate glycolysis and other cellular metabolic pathways. These metabolic pathways are essential not only for energy usage, but also for specialized effector actions, such as the production of reactive oxygen species (ROS), chemotaxis, phagocytosis, degranulation, and the formation of neutrophil extracellular traps (NETs). It has been demonstrated that activated viable neutrophils can produce NETs, which consists of a DNA scaffold able to bind granule proteins and microorganisms. The formation of NETs requires the availability of increased amounts of adenosine triphosphate (ATP) as it is an active cellular and therefore energy-dependent process. In this article, we discuss the glycolytic and other metabolic routes in association with neutrophil functions focusing on their role for building up NETs in the extracellular space. A better understanding of the requirements of metabolic pathways for neutrophil functions may lead to the discovery of molecular targets suitable to develop novel anti-infectious and/or anti-inflammatory drugs.
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Affiliation(s)
- Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland.,Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Lea Gigon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shuang Peng
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Robert Lukowski
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Alexander Karaulov
- Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia
| | - Albert Rizvanov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Nickolai A Barlev
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.,Regulation of Cell Signaling Laboratory, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland.,Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia.,Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia.,Institute of Biochemistry, Brandenburg Medical School, Neuruppin, Germany
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9
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Germic N, Fettrelet T, Stojkov D, Hosseini A, Horn MP, Karaulov A, Simon D, Yousefi S, Simon HU. The Release Kinetics of Eosinophil Peroxidase and Mitochondrial DNA Is Different in Association with Eosinophil Extracellular Trap Formation. Cells 2021; 10:cells10020306. [PMID: 33546138 PMCID: PMC7913244 DOI: 10.3390/cells10020306] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 01/29/2021] [Accepted: 01/30/2021] [Indexed: 01/03/2023] Open
Abstract
Eosinophils are a subset of granulocytes characterized by a high abundance of specific granules in their cytoplasm. To act as effector cells, eosinophils degranulate and form eosinophil extracellular traps (EETs), which contain double-stranded DNA (dsDNA) co-localized with granule proteins. The exact molecular mechanism of EET formation remains unknown. Although the term “EET release” has been used in scientific reports, it is unclear whether EETs are pre-formed in eosinophils and subsequently released. Moreover, although eosinophil degranulation has been extensively studied, a precise time-course of granule protein release has not been reported until now. In this study, we investigated the time-dependent release of eosinophil peroxidase (EPX) and mitochondrial DNA (mtDNA) following activation of both human and mouse eosinophils. Unexpectedly, maximal degranulation was already observed within 1 min with no further change upon complement factor 5 (C5a) stimulation of interleukin-5 (IL-5) or granulocyte/macrophage colony-stimulating factor (GM-CSF)-primed eosinophils. In contrast, bulk mtDNA release in the same eosinophil populations occurred much slower and reached maximal levels between 30 and 60 min. Although no single-cell analyses have been performed, these data suggest that the molecular pathways leading to degranulation and mtDNA release are at least partially different. Moreover, based on these data, it is likely that the association between the mtDNA scaffold and granule proteins in the process of EET formation occurs in the extracellular space.
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Affiliation(s)
- Nina Germic
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, CH-3010 Bern, Switzerland; (N.G.); (T.F.); (D.S.); (A.H.); (S.Y.)
| | - Timothée Fettrelet
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, CH-3010 Bern, Switzerland; (N.G.); (T.F.); (D.S.); (A.H.); (S.Y.)
- Department of Biochemistry, University of Lausanne, CH-1066 Epalinges, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, CH-3010 Bern, Switzerland; (N.G.); (T.F.); (D.S.); (A.H.); (S.Y.)
| | - Aref Hosseini
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, CH-3010 Bern, Switzerland; (N.G.); (T.F.); (D.S.); (A.H.); (S.Y.)
| | - Michael P. Horn
- Department of Clinical Chemistry, Inselspital, Bern University Hospital, University of Bern, CH-3010 Bern, Switzerland;
| | - Alexander Karaulov
- Department of Clinical Immunology and Allergology, Sechenov University, 119991 Moscow, Russia;
| | - Dagmar Simon
- Department of Dermatology, Inselspital, Bern University Hospital, University of Bern, CH-3010 Bern, Switzerland;
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, CH-3010 Bern, Switzerland; (N.G.); (T.F.); (D.S.); (A.H.); (S.Y.)
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, CH-3010 Bern, Switzerland; (N.G.); (T.F.); (D.S.); (A.H.); (S.Y.)
- Department of Clinical Immunology and Allergology, Sechenov University, 119991 Moscow, Russia;
- Laboratory of Molecular Immunology, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420012 Kazan, Russia
- Correspondence: ; Tel.: +41-31-632-3281
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Wang X, Gessier F, Perozzo R, Stojkov D, Hosseini A, Amirshahrokhi K, Kuchen S, Yousefi S, Lötscher P, Simon HU. RIPK3–MLKL–Mediated Neutrophil Death Requires Concurrent Activation of Fibroblast Activation Protein-α. J I 2020; 205:1653-1663. [DOI: 10.4049/jimmunol.2000113] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 07/21/2020] [Indexed: 12/30/2022]
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Frangež Ž, Fernández-Marrero Y, Stojkov D, Seyed Jafari SM, Hunger RE, Djonov V, Riether C, Simon HU. BIF-1 inhibits both mitochondrial and glycolytic ATP production: its downregulation promotes melanoma growth. Oncogene 2020; 39:4944-4955. [PMID: 32493957 DOI: 10.1038/s41388-020-1339-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 05/19/2020] [Accepted: 05/27/2020] [Indexed: 11/09/2022]
Abstract
Endophilin B1, also known as BAX-interacting protein 1 (BIF-1), is part of the endophilin B protein family, and is a multifunctional protein involved in the regulation of apoptosis, autophagy, and mitochondrial morphology. The role of BIF-1 in cancer is controversial since previous reports indicated to both tumor-promoting and tumor-suppressive roles, perhaps depending on the cancer cell type. In the present study, we report that BIF-1 is significantly downregulated in both primary and metastatic melanomas, and that patients with high levels of BIF-1 expression exhibited a better overall survival. Depleting BIF-1 using CRISPR/Cas9 technology in melanoma cells resulted in higher proliferation rates both in vitro and in vivo, a finding that was associated with increased ATP production, metabolic acidification, and mitochondrial respiration. We also observed mitochondrial hyperpolarization, but no increase in the mitochondrial content of BIF-1-knockout melanoma cells. In contrast, such knockout melanoma cells were equally sensitive to anticancer drug- or UV irradiation-induced cell death, and exhibited similar autophagic activities as compared with control cells. Taken together, it appears that downregulation of BIF-1 contributes to tumorigenesis in cutaneous melanoma by upregulating mitochondrial respiration and metabolism, independent of its effect on apoptosis and autophagy.
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Affiliation(s)
- Živa Frangež
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | | | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - S Morteza Seyed Jafari
- Department of Dermatology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Robert E Hunger
- Department of Dermatology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | | | - Carsten Riether
- Tumor Immunology, Department for Biomedical Research, University of Bern, Bern, Switzerland.,Department of Medical Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland. .,Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia.
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12
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Yousefi S, Simon D, Stojkov D, Karsonova A, Karaulov A, Simon HU. In vivo evidence for extracellular DNA trap formation. Cell Death Dis 2020; 11:300. [PMID: 32355207 PMCID: PMC7193637 DOI: 10.1038/s41419-020-2497-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/01/2020] [Accepted: 04/14/2020] [Indexed: 12/14/2022]
Abstract
Extracellular DNA trap formation is a cellular function of neutrophils, eosinophils, and basophils that facilitates the immobilization and killing of invading microorganisms in the extracellular milieu. To form extracellular traps, granulocytes release a scaffold consisting of mitochondrial DNA in association with granule proteins. As we understand more about the molecular mechanism for the formation of extracellular DNA traps, the in vivo function of this phenomenon under pathological conditions remains an enigma. In this article, we critically review the literature to summarize the evidence for extracellular DNA trap formation under in vivo conditions. Extracellular DNA traps have not only been detected in infectious diseases but also in chronic inflammatory diseases, as well as in cancer. While on the one hand, extracellular DNA traps clearly exhibit an important function in host defense, it appears that they can also contribute to the maintenance of inflammation and metastasis, suggesting that they may represent an interesting drug target for such pathological conditions.
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Affiliation(s)
- Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Dagmar Simon
- Department of Dermatology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Antonina Karsonova
- Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia
| | - Alexander Karaulov
- Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland.
- Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia.
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Surmiak M, Gielicz A, Stojkov D, Szatanek R, Wawrzycka-Adamczyk K, Yousefi S, Simon HU, Sanak M. LTB 4 and 5-oxo-ETE from extracellular vesicles stimulate neutrophils in granulomatosis with polyangiitis. J Lipid Res 2020; 61:1-9. [PMID: 31740445 PMCID: PMC6939603 DOI: 10.1194/jlr.m092072] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 11/08/2019] [Indexed: 12/11/2022] Open
Abstract
Activation of neutrophils is an important mechanism in the pathology of granulomatosis with polyangiitis (GPA). In this study, we evaluated whether extracellular vesicles (EVs) circulating in the plasma of GPA patients could contribute to this process. EVs from the plasma of GPA patients in the active stage of the disease (n = 10) and healthy controls (n = 10) were isolated by ultracentrifugation and characterized by flow cytometry (CD63, CD8) and nanoparticle tracking analysis. Targeted oxylipin lipidomics of EVs was performed by HPLC-MS/MS. EV/oxylipin-induced neutrophil extracellular traps (NETs) were analyzed by confocal microscopy, and released double-stranded DNA (dsDNA) was quantified by PicoGreen fluorescent dye. Reactive oxygen species (ROS) production and neutrophils' EV binding/uptake were evaluated by flow cytometry. Brief priming with granulocyte-macrophage colony-stimulating factor was required for EV-mediated ROS production and dsDNA release. It was observed that priming also increased EV binding/uptake by neutrophils only for EVs from GPA patients. EVs from GPA patients had higher concentrations of leukotriene (LT)B4 and 5-oxo-eicosatetraenoic acid (5-oxo-ETE) as compared with EVs from healthy controls. Moreover, neutrophils stimulated with LTB4 or 5-oxo-ETE produced ROS and released dsDNA in a concentration-dependent manner. These results reveal the potential role of EVs containing oxylipin cargo on ROS production and NET formation by activated neutrophils.
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Affiliation(s)
- Marcin Surmiak
- Departments of Internal Medicine Jagiellonian University Medical College, Krakow, Poland
| | - Anna Gielicz
- Departments of Internal Medicine Jagiellonian University Medical College, Krakow, Poland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Rafał Szatanek
- Clinical Immunology, Jagiellonian University Medical College, Krakow, Poland
| | | | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Marek Sanak
- Departments of Internal Medicine Jagiellonian University Medical College, Krakow, Poland.
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14
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Gjuroski I, Girousi E, Meyer C, Hertig D, Stojkov D, Fux M, Schnidrig N, Bucher J, Pfister S, Sauser L, Simon HU, Vermathen P, Furrer J, Vermathen M. Evaluation of polyvinylpyrrolidone and block copolymer micelle encapsulation of serine chlorin e6 and chlorin e4 on their reactivity towards albumin and transferrin and their cell uptake. J Control Release 2019; 316:150-167. [PMID: 31689463 DOI: 10.1016/j.jconrel.2019.10.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 09/02/2019] [Accepted: 10/02/2019] [Indexed: 01/10/2023]
Abstract
Encapsulation of porphyrinic photosensitizers (PSs) into polymeric carriers plays an important role in enhancing their efficiency as drugs in photodynamic therapy (PDT). Porphyrin aggregation and low solubility as well as the preservation of the advantageous photophysical properties pose a challenge on the design of efficient PS-carrier systems. Block copolymer micelles (BCMs) and polyvinylpyrrolidone (PVP) are promising drug delivery vehicles for physical entrapment of PSs. BCMs exhibit enhanced dynamics as compared to the less flexible PVP network. In the current work the question is addressed how these different dynamics affect PS encapsulation, release from the carrier, reaction with serum proteins, and cellular uptake. The porphyrinic compounds serine-amide of chlorin e6 (SerCE) and chlorin e4 (CE4) were used as model PSs with different lipophilicity and aggregation properties. 1H NMR and fluorescence spectroscopy were applied to study their interactions with PVP and BCMs consisting of Kolliphor P188 (KP). Both chlorins were well encapsulated by the carriers and had improved photophysical properties. Compared to SerCE, the more lipophilic CE4 exhibited stronger hydrophobic interactions with the BCM core, stabilizing the system and preventing exchange with the surrounding medium as was shown by NMR NOESY and DOSY experiments. PVP and BCMs protected the encapsulated chlorins against interaction with human transferrin (Tf). However, SerCE and CE4 were released from BCMs in favor of binding to human serum albumin (HSA) while PVP prevented interaction with HSA. Fluorescence spectroscopic studies revealed that HSA binds to the surface of PVP forming a protein corona. PVP and BCMs reduced cellular uptake of the chlorins. However, encapsulation into BCMs resulted in more efficient cell internalization for CE4 than for SerCE. HSA significantly lowered both, free and carrier-mediated cell uptake for CE4 and SerCE. In conclusion, PVP appears as the more universal delivery system covering a broad range of host molecules with respect to polarity, whereas BCMs require a higher drug-carrier compatibility. Poorly soluble hydrophobic PSs benefit stronger from BCM-type carriers due to enhanced bioavailability through disaggregation and solubilization allowing for more efficient cell uptake. In addition, increased PS-carrier hydrophobic interactions have a stabilizing effect. For more hydrophilic PSs, the main advantage of polymeric carriers like PVP or poloxamer micelles lies in their protection during the transport through the bloodstream. HSA binding plays an important role for drug release and cell uptake in carrier-mediated delivery to the target tissue.
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Affiliation(s)
- Ilche Gjuroski
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland.
| | - Eleftheria Girousi
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Christoph Meyer
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Damian Hertig
- Department of BioMedical Research and Radiology, University of Bern and Inselspital, sitem-insel AG, Freiburgstrasse 3, CH-3010, Bern, Switzerland; Institute of Clinical Chemistry, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Michaela Fux
- Institute of Clinical Chemistry, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Nicolas Schnidrig
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Jan Bucher
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Sara Pfister
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Luca Sauser
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern and Inselspital, CH-3010, Bern, Switzerland
| | - Peter Vermathen
- Department of BioMedical Research and Radiology, University of Bern and Inselspital, sitem-insel AG, Freiburgstrasse 3, CH-3010, Bern, Switzerland
| | - Julien Furrer
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Martina Vermathen
- University of Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, CH-3012, Bern, Switzerland.
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15
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Boeltz S, Amini P, Anders HJ, Andrade F, Bilyy R, Chatfield S, Cichon I, Clancy DM, Desai J, Dumych T, Dwivedi N, Gordon RA, Hahn J, Hidalgo A, Hoffmann MH, Kaplan MJ, Knight JS, Kolaczkowska E, Kubes P, Leppkes M, Manfredi AA, Martin SJ, Maueröder C, Maugeri N, Mitroulis I, Munoz LE, Nakazawa D, Neeli I, Nizet V, Pieterse E, Radic MZ, Reinwald C, Ritis K, Rovere-Querini P, Santocki M, Schauer C, Schett G, Shlomchik MJ, Simon HU, Skendros P, Stojkov D, Vandenabeele P, Berghe TV, van der Vlag J, Vitkov L, von Köckritz-Blickwede M, Yousefi S, Zarbock A, Herrmann M. To NET or not to NET:current opinions and state of the science regarding the formation of neutrophil extracellular traps. Cell Death Differ 2019; 26:395-408. [PMID: 30622307 PMCID: PMC6370810 DOI: 10.1038/s41418-018-0261-x] [Citation(s) in RCA: 257] [Impact Index Per Article: 51.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 11/05/2018] [Accepted: 11/30/2018] [Indexed: 12/16/2022] Open
Abstract
Since the discovery and definition of neutrophil extracellular traps (NETs) 14 years ago, numerous characteristics and physiological functions of NETs have been uncovered. Nowadays, the field continues to expand and novel mechanisms that orchestrate formation of NETs, their previously unknown properties, and novel implications in disease continue to emerge. The abundance of available data has also led to some confusion in the NET research community due to contradictory results and divergent scientific concepts, such as pro- and anti-inflammatory roles in pathologic conditions, demarcation from other forms of cell death, or the origin of the DNA that forms the NET scaffold. Here, we present prevailing concepts and state of the science in NET-related research and elaborate on open questions and areas of dispute.
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Affiliation(s)
- Sebastian Boeltz
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
| | - Poorya Amini
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Joachim Anders
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Felipe Andrade
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rostyslav Bilyy
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Simon Chatfield
- Inflammation Division, Walter and Eliza Hall Institute, Melbourne, Victoria, Australia
| | - Iwona Cichon
- Department of Experimental Hematology, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland
| | - Danielle M Clancy
- VIB-UGent Center for Inflammation Research, University of Gent, Gent, Belgium
| | - Jyaysi Desai
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Tetiana Dumych
- Danylo Halytsky Lviv National Medical University, Lviv, Ukraine
| | - Nishant Dwivedi
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Rachael Ann Gordon
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jonas Hahn
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
| | - Andrés Hidalgo
- Department of Cell and Developmental Biology, Fundación Centro Nacional de Investigaciones Cardiovasculares (CNIC) Carlos III, Madrid, Spain
- Institute for Cardiovascular Prevention, Ludwig Maximilians University, Munich, Germany
| | - Markus H Hoffmann
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany.
| | - Mariana J Kaplan
- Systemic Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, USA
| | - Jason S Knight
- Division of Rheumatology, University of Michigan, Ann Arbor, MI, USA
| | - Elzbieta Kolaczkowska
- Department of Experimental Hematology, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland
| | - Paul Kubes
- Snyder institute of Chronic Diseases, University of Calgary, Calgary, Canada
| | - Moritz Leppkes
- Department of Medicine 1 - Gastroenterology, Pulmonology and Endocrinology, Universitätsklinikum Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Angelo A Manfredi
- Università Vita Salute San Raffaele and IRCCS Ospedale San Raffaele, Milan, Italy
| | - Seamus J Martin
- Molecular Cell Biology Laboratory, Department of Genetics, The Smurfit Institute, Trinity College, Dublin 2, Ireland
| | - Christian Maueröder
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
- VIB-UGent Center for Inflammation Research, University of Gent, Gent, Belgium
| | - Norma Maugeri
- Università Vita Salute San Raffaele and IRCCS Ospedale San Raffaele, Milan, Italy
| | - Ioannis Mitroulis
- Laboratory of Molecular Hematology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
- First Department of Internal Medicine, University Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, Greece
| | - Luis E Munoz
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
| | - Daigo Nakazawa
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Munich, Germany
| | - Indira Neeli
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Victor Nizet
- UC San Diego School of Medicine, La Jolla, CA, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, UC San Diego, La Jolla, CA, USA
| | - Elmar Pieterse
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Marko Z Radic
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Christiane Reinwald
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
| | - Konstantinos Ritis
- Laboratory of Molecular Hematology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
- First Department of Internal Medicine, University Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, Greece
| | | | - Michal Santocki
- Department of Experimental Hematology, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland
| | - Christine Schauer
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
| | - Georg Schett
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
| | - Mark Jay Shlomchik
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
- Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia
| | - Panagiotis Skendros
- Laboratory of Molecular Hematology, Department of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
- First Department of Internal Medicine, University Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, Greece
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Peter Vandenabeele
- VIB-UGent Center for Inflammation Research, University of Gent, Gent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Methusalem platform, Ghent University, Ghent, Belgium
| | - Tom Vanden Berghe
- VIB-UGent Center for Inflammation Research, University of Gent, Gent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Laboratory of Pathophysiology, Faculty of Biomedical Sciences, University of Antwerp, Wilrijk, Belgium
| | - Johan van der Vlag
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ljubomir Vitkov
- Department of Biosciences, Vascular & Exercise Biology Unit, University of Salzburg, Salzburg, Austria
- Periodontology and Preventive Dentistry, Saarland University, Homburg, Germany
| | - Maren von Köckritz-Blickwede
- Department of Physiological Chemistry & Research Center for Emerging Infections and Zoonosis (RIZ), University of Veterinary Medicine Hannover, Hannover, Germany
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Alexander Zarbock
- University of Münster, Department of Anesthesiology, Intensive Care and Pain Medicine, Münster, Germany
| | - Martin Herrmann
- Department of Internal Medicine 3 - Rheumatology and Immunology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, 91054, Erlangen, Germany
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16
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Yadav SK, Stojkov D, Feigelson SW, Roncato F, Simon HU, Yousefi S, Alon R. Chemokine-triggered microtubule polymerization promotes neutrophil chemotaxis and invasion but not transendothelial migration. J Leukoc Biol 2019; 105:755-766. [PMID: 30802327 DOI: 10.1002/jlb.3a1118-437rr] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 02/03/2019] [Accepted: 02/04/2019] [Indexed: 12/29/2022] Open
Abstract
Microtubules (MTs) are critically involved in the transport of material within cells, but their roles in chemotactic leukocyte motility and effector functions are still obscure. Resting neutrophils contain few MTs assembled in an MT organizing center (MTOC) behind their multilobular nuclei. Using a probe of real-time tubulin polymerization, SiR-tubulin, we found that neutrophils elongated their MTs within minutes in response to signals from the two prototypic chemotactic peptides, CXCL1 and fMLP. Taxol, a beta-tubulin binding and MT stabilizing drug, was found to abolish this CXCL1- and fMLP-stimulated MT polymerization. Nevertheless, taxol treatment as well as disruption of existing and de novo generated MTs did not impair neutrophil protrusion and squeezing through IL-1β-stimulated endothelial monolayers mediated by endothelial deposited CXCL1 and neutrophil CXCR2. Notably, CXCL1-dependent neutrophil TEM was not associated with neutrophil MT polymerization. Chemokinetic neutrophil motility on immobilized CXCL1 was also not associated with MT polymerization, and taxol treatment did not interfere with this motility. Nevertheless, and consistent with its ability to suppress MT polymerization induced by soluble CXCL1 and fMLP, taxol treatment inhibited neutrophil chemotaxis toward both chemotactic peptides. Taxol treatment also suppressed CXCL1- and fMLP-triggered elastase-dependent neutrophil invasion through collagen I barriers. Collectively, our results highlight de novo chemoattractant-triggered MT polymerization as key for neutrophil chemotaxis and elastase-dependent invasion but not for chemotactic neutrophil crossing of inflamed endothelial barriers.
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Affiliation(s)
- Sandeep Kumar Yadav
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Sara W Feigelson
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
| | - Francesco Roncato
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Ronen Alon
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
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17
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Yousefi S, Qu W, Flayer CH, Stojkov D, Germic N, Aeschlimann S, Ge MQ, Simon HU, Haczku A. Surfactant Protein D (SP-D) Inhibits Neutrophil Extracellular DNA Trap Formation: Effects of S-nitrosylation. J Allergy Clin Immunol 2019. [DOI: 10.1016/j.jaci.2018.12.588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Yousefi S, Stojkov D, Germic N, Simon D, Wang X, Benarafa C, Simon HU. Untangling "NETosis" from NETs. Eur J Immunol 2019; 49:221-227. [PMID: 30629284 DOI: 10.1002/eji.201747053] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 11/14/2018] [Accepted: 01/02/2019] [Indexed: 12/29/2022]
Abstract
Neutrophil extracellular trap (NET) formation is a cellular function of neutrophils that facilitates the immobilization and killing of invading microorganisms in the extracellular milieu. To form NETs, neutrophils release a DNA scaffold consisting of mitochondrial DNA binding granule proteins. This process does not depend on cell death, but requires glycolytic ATP production for rearrangements in the microtubule network and F-actin. Such cytoskeletal rearrangements are essential for both mitochondrial DNA release and degranulation. However, the formation of NETs has also been described as a distinct form of programed, necrotic cell death, a process designated "NETosis." Necrotic cell death of neutrophils is associated with the permeabilization of both plasma and nuclear membranes resulting in a kind of extracellular cloud of nuclear DNA. The molecular mechanisms eliciting necrotic neutrophil death have been investigated and appear to be different from those responsible for NET formation following mitochondrial DNA release. Here, we discriminate between the mechanisms responsible for the release of mitochondrial versus nuclear DNA and address their respective functions. Our aim is to clarify existing differences of opinion in the fields of NET formation and neutrophil death.
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Affiliation(s)
- Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Nina Germic
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Dagmar Simon
- Department of Dermatology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Xiaoliang Wang
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Charaf Benarafa
- Institute of Virology and Immunology, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland.,Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia
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19
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Amini P, Stojkov D, Felser A, Jackson CB, Courage C, Schaller A, Gelman L, Soriano ME, Nuoffer JM, Scorrano L, Benarafa C, Yousefi S, Simon HU. Neutrophil extracellular trap formation requires OPA1-dependent glycolytic ATP production. Nat Commun 2018; 9:2958. [PMID: 30054480 PMCID: PMC6063938 DOI: 10.1038/s41467-018-05387-y] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 07/03/2018] [Indexed: 01/21/2023] Open
Abstract
Optic atrophy 1 (OPA1) is a mitochondrial inner membrane protein that has an important role in mitochondrial fusion and structural integrity. Dysfunctional OPA1 mutations cause atrophy of the optic nerve leading to blindness. Here, we show that OPA1 has an important role in the innate immune system. Using conditional knockout mice lacking Opa1 in neutrophils (Opa1N∆), we report that lack of OPA1 reduces the activity of mitochondrial electron transport complex I in neutrophils. This then causes a decline in adenosine-triphosphate (ATP) production through glycolysis due to lowered NAD+ availability. Additionally, we show that OPA1-dependent ATP production in these cells is required for microtubule network assembly and for the formation of neutrophil extracellular traps. Finally, we show that Opa1N∆ mice exhibit a reduced antibacterial defense capability against Pseudomonas aeruginosa. Optic atrophy 1 (OPA1) is known to be important for mitochondrial fusion and structural integrity. Here, using OPA1 knockout mice, the authors show a detrimental effect on host defense capabilities against pathogen infections. This study reports a critical role for OPA1 in innate immunity.
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Affiliation(s)
- Poorya Amini
- Institute of Pharmacology, University of Bern, 3010, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, 3010, Bern, Switzerland
| | - Andrea Felser
- University Institute of Clinical Chemistry, Bern University Hospital, 3010, Bern, Switzerland
| | - Christopher B Jackson
- Research Program for Molecular Neurology, Biomedicum Helsinki, University of Helsinki, 00290, Helsinki, Finland
| | - Carolina Courage
- Division of Human Genetics and Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, 3010, Bern, Switzerland
| | - André Schaller
- Division of Human Genetics and Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, 3010, Bern, Switzerland
| | - Laurent Gelman
- Friedrich Miescher Institute for Biomedical Research, 4058, Basel, Switzerland
| | | | - Jean-Marc Nuoffer
- University Institute of Clinical Chemistry, Bern University Hospital, 3010, Bern, Switzerland
| | - Luca Scorrano
- Venetian Institute of Molecular Medicine (VIMM), 35129, Padua, Italy
| | - Charaf Benarafa
- Institute of Virology and Immunology, 3147, Mittelhäusern, Switzerland.,Department of Infectious Diseases and Pathology, Vetsuisse Faculty, University of Bern, 3012, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, 3010, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, 3010, Bern, Switzerland.
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20
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Yousefi S, Sharma SK, Stojkov D, Germic N, Aeschlimann S, Ge MQ, Flayer CH, Larson ED, Redai IG, Zhang S, Koziol-White CJ, Karikó K, Simon HU, Haczku A. Oxidative damage of SP-D abolishes control of eosinophil extracellular DNA trap formation. J Leukoc Biol 2018; 104:205-214. [PMID: 29733456 DOI: 10.1002/jlb.3ab1117-455r] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 03/13/2018] [Accepted: 03/27/2018] [Indexed: 12/25/2022] Open
Abstract
The asthmatic airways are highly susceptible to inflammatory injury by air pollutants such as ozone (O3 ), characterized by enhanced activation of eosinophilic granulocytes and a failure of immune protective mechanisms. Eosinophil activation during asthma exacerbation contributes to the proinflammatory oxidative stress by high levels of nitric oxide (NO) production and extracellular DNA release. Surfactant protein-D (SP-D), an epithelial cell product of the airways, is a critical immune regulatory molecule with a multimeric structure susceptible to oxidative modifications. Using recombinant proteins and confocal imaging, we demonstrate here that SP-D directly bound to the membrane and inhibited extracellular DNA trap formation by human and murine eosinophils in a concentration and carbohydrate-dependent manner. Combined allergic airway sensitization and O3 exposure heightened eosinophilia and nos2 mRNA (iNOS) activation in the lung tissue and S-nitrosylation related de-oligomerisation of SP-D in the airways. In vitro reproduction of the iNOS action led to similar effects on SP-D. Importantly, S-nitrosylation abolished the ability of SP-D to block extracellular DNA trap formation. Thus, the homeostatic negative regulatory feedback between SP-D and eosinophils is destroyed by the NO-rich oxidative lung tissue environment in asthma exacerbations.
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Affiliation(s)
| | | | | | | | | | - Moyar Q Ge
- University of Pennsylvania, Philadelphia, Pennsylvania, USA.,University of California, Davis, California, USA
| | | | | | - Imre G Redai
- University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Suhong Zhang
- University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Cynthia J Koziol-White
- University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Rutgers University, New Brunswick, New Jersey, USA
| | - Katalin Karikó
- University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Angela Haczku
- University of Pennsylvania, Philadelphia, Pennsylvania, USA.,University of California, Davis, California, USA
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21
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Stojkov D, Amini P, Oberson K, Sokollik C, Duppenthaler A, Simon HU, Yousefi S. ROS and glutathionylation balance cytoskeletal dynamics in neutrophil extracellular trap formation. J Cell Biol 2017; 216:4073-4090. [PMID: 29150539 PMCID: PMC5716265 DOI: 10.1083/jcb.201611168] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 06/27/2017] [Accepted: 08/22/2017] [Indexed: 12/26/2022] Open
Abstract
Neutrophils can release their genomic DNA as extracellular traps (NETs), which ensnare bacteria and limit their replication. Stojkov et al. find that modulation of cytoskeletal dynamics by reactive oxygen species and glutathionylation controls the degranulation and release of mitochondrial DNA required for NET formation. The antimicrobial defense activity of neutrophils partly depends on their ability to form neutrophil extracellular traps (NETs), but the underlying mechanism controlling NET formation remains unclear. We demonstrate that inhibiting cytoskeletal dynamics with pharmacological agents or by genetic manipulation prevents the degranulation of neutrophils and mitochondrial DNA release required for NET formation. Wiskott-Aldrich syndrome protein–deficient neutrophils are unable to polymerize actin and exhibit a block in both degranulation and DNA release. Similarly, neutrophils with a genetic defect in NADPH oxidase fail to induce either actin and tubulin polymerization or NET formation on activation. Moreover, neutrophils deficient in glutaredoxin 1 (Grx1), an enzyme required for deglutathionylation of actin and tubulin, are unable to polymerize either cytoskeletal network and fail to degranulate or release DNA. Collectively, cytoskeletal dynamics are achieved as a balance between reactive oxygen species–regulated effects on polymerization and glutathionylation on the one hand and the Grx1-mediated deglutathionylation that is required for NET formation on the other.
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Affiliation(s)
- Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Poorya Amini
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Kevin Oberson
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Christiane Sokollik
- Unit of Pediatric Infectious Diseases, University Children's Hospital Bern, Bern, Switzerland
| | - Andrea Duppenthaler
- Unit of Pediatric Infectious Diseases, University Children's Hospital Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
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22
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Germic N, Stojkov D, Oberson K, Yousefi S, Simon HU. Neither eosinophils nor neutrophils require ATG5-dependent autophagy for extracellular DNA trap formation. Immunology 2017; 152:517-525. [PMID: 28703297 DOI: 10.1111/imm.12790] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 07/06/2017] [Accepted: 07/06/2017] [Indexed: 12/18/2022] Open
Abstract
The importance of extracellular traps (ETs) in innate immunity is well established, but the molecular mechanisms responsible for their formation remain unclear and in scientific dispute. ETs have been defined as extracellular DNA scaffolds associated with the granule proteins of eosinophils or neutrophils. They are capable of killing bacteria extracellularly. Based mainly on results with phosphoinositide 3-kinase (PI3K) inhibitors such as 3-methyladenine (3-MA) and wortmannin, which are commonly used to inhibit autophagy, several groups have reported that autophagy is required for neutrophil extracellular trap (NET) formation. We decided to investigate this apparent dependence on autophagy for ET release and generated genetically modified mice that lack, specifically in eosinophils or neutrophils, autophagy-related 5 (Atg5), a gene encoding a protein essential for autophagosome formation. Interestingly, neither eosinophils nor neutrophils from Atg5-deficient mice exhibited abnormalities in ET formation upon physiological activation or exposure to low concentrations of PMA, although we could confirm that human and mouse eosinophils and neutrophils, after pre-treatment with inhibitors of class III PI3K, show a block both in reactive oxygen species (ROS) production and in ET formation. The so-called late autophagy inhibitors bafilomycin A1 and chloroquine, on the other hand, were without effect. These data indicate that ET formation occurs independently of autophagy and that the inhibition of ROS production and ET formation in the presence of 3-MA and wortmannin is probably owing to their additional ability to block the class I PI3Ks, which are involved in signalling cascades initiated by triggers of ET formation.
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Affiliation(s)
- Nina Germic
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Kevin Oberson
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
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23
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Amini P, Stojkov D, Wang X, Wicki S, Kaufmann T, Wong WWL, Simon HU, Yousefi S. NET formation can occur independently of RIPK3 and MLKL signaling. Eur J Immunol 2015; 46:178-84. [PMID: 26549703 PMCID: PMC4738457 DOI: 10.1002/eji.201545615] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 10/05/2015] [Accepted: 11/03/2015] [Indexed: 12/14/2022]
Abstract
The importance of neutrophil extracellular traps (NETs) in innate immunity is well established but the molecular mechanisms responsible for their formation are still a matter of scientific dispute. Here, we aim to characterize a possible role of the receptor‐interacting protein kinase 3 (RIPK3) and the mixed lineage kinase domain‐like (MLKL) signaling pathway, which are known to cause necroptosis, in NET formation. Using genetic and pharmacological approaches, we investigated whether this programmed form of necrosis is a prerequisite for NET formation. NETs have been defined as extracellular DNA scaffolds associated with the neutrophil granule protein elastase that are capable of killing bacteria. Neither Ripk3‐deficient mouse neutrophils nor human neutrophils in which MLKL had been pharmacologically inactivated, exhibited abnormalities in NET formation upon physiological activation or exposure to low concentrations of PMA. These data indicate that NET formation occurs independently of both RIPK3 and MLKL signaling.
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Affiliation(s)
- Poorya Amini
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Darko Stojkov
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Xiaoliang Wang
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Simone Wicki
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Thomas Kaufmann
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Wendy Wei-Lynn Wong
- Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Bern, Switzerland
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24
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Yousefi S, Morshed M, Amini P, Stojkov D, Simon D, von Gunten S, Kaufmann T, Simon HU. Basophils exhibit antibacterial activity through extracellular trap formation. Allergy 2015; 70:1184-8. [PMID: 26043360 DOI: 10.1111/all.12662] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/29/2015] [Indexed: 01/21/2023]
Abstract
Basophils are primarily associated with immunomodulatory functions in allergic diseases and parasitic infections. Recently, it has been demonstrated that both activated human and mouse basophils can form extracellular DNA traps (BETs) containing mitochondrial DNA and granule proteins. In this report, we provide evidence that, in spite of an apparent lack of phagocytic activity, basophils can kill bacteria through BET formation.
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Affiliation(s)
- S. Yousefi
- Institute of Pharmacology; University of Bern; Bern Switzerland
| | - M. Morshed
- Institute of Pharmacology; University of Bern; Bern Switzerland
| | - P. Amini
- Institute of Pharmacology; University of Bern; Bern Switzerland
| | - D. Stojkov
- Institute of Pharmacology; University of Bern; Bern Switzerland
| | - D. Simon
- Department of Dermatology; Inselspital, Bern University Hospital; Bern Switzerland
| | - S. von Gunten
- Institute of Pharmacology; University of Bern; Bern Switzerland
| | - T. Kaufmann
- Institute of Pharmacology; University of Bern; Bern Switzerland
| | - H.-U. Simon
- Institute of Pharmacology; University of Bern; Bern Switzerland
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25
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Bjelobaba I, Lavrnja I, Parabucki A, Stojkov D, Stojiljkovic M, Pekovic S, Nedeljkovic N. The cortical stab injury induces beading of fibers expressing ecto-nucleoside triphosphate diphosphohydrolase 3. Neuroscience 2010; 170:107-16. [PMID: 20620196 DOI: 10.1016/j.neuroscience.2010.06.063] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 06/24/2010] [Accepted: 06/24/2010] [Indexed: 01/03/2023]
Abstract
The ecto-nucleoside triphosphate diphosphohydrolase 3 (NTPDase3), an enzyme involved in degradation of extracellular adenosine triphosphate (ATP), is expressed on nerve fibers in different brain regions, including cortex. Here we studied the expression and role of this enzyme after unilateral cortical stab injury in rats. In cortical sections of control rats, NTPDase3 immunoreactivity was associated with two types of fibers: thin processes, occasionally with small mushroom-like protrusions and slightly thicker fibers with more pronounced and more frequent varicosities, whereas immunopositive neuronal perycaria were never observed. Although NTPDase3-positive thin processes and thicker fibers, by general appearance, size and shape, could be dendrites and axons, respectively, they were never immunopositive for microtubule associated protein-2 or neurofilament H subunit. Cortical stab injury induced rapid (within 4 hours) focal varicose swelling that evolved over time to prominent beading of NTPDase3-positive fibers. The NTPDase3-positive fibers in all experimental groups also abundantly express NTPDase1, ecto-5'-nucleotidase and P2X2 receptor channels. Because the brain injury causes a massive ATP release, it is reasonable to conclude that purinoreceptors and ectonucleotidases play an important role in the process of neuritic beading.
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Affiliation(s)
- I Bjelobaba
- Department for Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bulevar Despota Stefana 142, 11000 Belgrade, Republic of Serbia.
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