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Li XX, Fung JN, Clark RJ, Lee JD, Woodruff TM. Cell-intrinsic C5a synergizes with Dectin-1 in macrophages to mediate fungal killing. Proc Natl Acad Sci U S A 2024; 121:e2314627121. [PMID: 38252818 PMCID: PMC10835034 DOI: 10.1073/pnas.2314627121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 12/20/2023] [Indexed: 01/24/2024] Open
Abstract
The complement factor C5a is a core effector product of complement activation. C5a, acting through its receptors C5aR1 and C5aR2, exerts pleiotropic immunomodulatory functions in myeloid cells, which is vital for host defense against pathogens. Pattern-recognition receptors (PRRs) are similarly expressed by immune cells as detectors of pathogen-associated molecular patterns. Although there is evidence of cross talk between complement and PRR signaling pathways, knowledge of the full potential for C5a-PRR interaction is limited. In this study, we comprehensively investigated how C5a signaling through C5a receptors can modulate diverse PRR-mediated cytokine responses in human primary monocyte-derived macrophages and observed a powerful, concentration-dependent bidirectional effect of C5a on PRR activities. Unexpectedly, C5a synergized with Dectin-1, Mincle, and STING in macrophages to a much greater extent than TLRs. Notably, we also identified that selective Dectin-1 activation using depleted zymosan triggered macrophages to generate cell-intrinsic C5a, which acted on intracellular and cell surface C5aR1, to help sustain mitochondrial ROS generation, up-regulate TNFα production, and enhance fungal killing. This study adds further evidence to the holistic functions of C5a as a central immunomodulator and important orchestrator of pathogen sensing and killing by phagocytes.
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Affiliation(s)
- Xaria X. Li
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD4072, Australia
| | - Jenny N. Fung
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD4072, Australia
| | - Richard J. Clark
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD4072, Australia
| | - John D. Lee
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD4072, Australia
| | - Trent M. Woodruff
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD4072, Australia
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2
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Fiebig A, Leibl V, Oostendorf D, Lukaschek S, Frömbgen J, Masoudi M, Kremer AE, Strupf M, Reeh P, Düll M, Namer B. Peripheral signaling pathways contributing to non-histaminergic itch in humans. J Transl Med 2023; 21:908. [PMID: 38087354 PMCID: PMC10717026 DOI: 10.1186/s12967-023-04698-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/04/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Chronic itch (chronic pruritus) is a major therapeutic challenge that remains poorly understood despite the extensive recent analysis of human pruriceptors. It is unclear how the peripheral nervous system differentiates the signaling of non-histaminergic itch and pain. METHODS Here we used psychophysical analysis and microneurography (single nerve fiber recordings) in healthy human volunteers to explore the distinct signaling mechanisms of itch, using the pruritogens β-alanine, BAM 8-22 and cowhage extract. RESULTS The mode of application (injection or focal application using inactivated cowhage spicules) influenced the itch/pain ratio in sensations induced by BAM 8-22 and cowhage but not β-alanine. We found that sensitizing pre-injections of prostaglandin E2 increased the pain component of BAM 8-22 but not the other pruritogens. A-fibers contributed only to itch induced by β-alanine. TRPV1 and TRPA1 were necessary for itch signaling induced by all three pruritogens. In single-fiber recordings, we found that BAM 8-22 and β-alanine injection activated nearly all CM-fibers (to different extents) but not CMi-fibers, whereas cowhage extract injection activated only 56% of CM-fibers but also 25% of CMi-fibers. A "slow bursting discharge pattern" was evoked in 25% of CM-fibers by β-alanine, in 35% by BAM 8-22, but in only 10% by cowhage extract. CONCLUSION Our results indicate that no labeled line exists for these pruritogens in humans. A combination of different mechanisms, specific for each pruritogen, leads to itching sensations rather than pain. Notably, non-receptor-based mechanisms such as spatial contrast or discharge pattern coding seem to be important processes. These findings will facilitate the discovery of therapeutic targets for chronic pruritus, which are unlikely to be treated effectively by single receptor blockade.
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Affiliation(s)
- Andrea Fiebig
- Research Group Neuroscience, Interdisciplinary Centre for Clinical Research, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neurophysiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Victoria Leibl
- Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - David Oostendorf
- Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Saskia Lukaschek
- Research Group Neuroscience, Interdisciplinary Centre for Clinical Research, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neurophysiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Jens Frömbgen
- Research Group Neuroscience, Interdisciplinary Centre for Clinical Research, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Institute of Neurophysiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Maral Masoudi
- Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Andreas E Kremer
- Department of Gastroenterology and Hepatology, University Hospital Zürich, University of Zürich, Zurich, Switzerland
| | - Marion Strupf
- Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Peter Reeh
- Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Miriam Düll
- Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, 91054, Erlangen, Germany
- Department of Medicine 1, University Hospital Erlangen and Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Barbara Namer
- Research Group Neuroscience, Interdisciplinary Centre for Clinical Research, Faculty of Medicine, RWTH Aachen University, Aachen, Germany.
- Institute of Neurophysiology, Uniklinik RWTH Aachen University, Aachen, Germany.
- Institute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, 91054, Erlangen, Germany.
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3
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Schmitz GP, Roth BL. G protein-coupled receptors as targets for transformative neuropsychiatric therapeutics. Am J Physiol Cell Physiol 2023; 325:C17-C28. [PMID: 37067459 PMCID: PMC10281788 DOI: 10.1152/ajpcell.00397.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 03/28/2023] [Accepted: 04/06/2023] [Indexed: 04/18/2023]
Abstract
G protein-coupled receptors (GPCRs) constitute the largest family of druggable genes in the human genome. Even though perhaps 30% of approved medications target GPCRs, they interact with only a small number of them. Here, we consider whether there might be new opportunities for transformative therapeutics for neuropsychiatric disorders by specifically targeting both known and understudied GPCRs. Using psychedelic drugs that target serotonin receptors as an example, we show how recent insights into the structure, function, signaling, and cell biology of these receptors have led to potentially novel therapeutics. We next focus on the possibility that nonpsychedelic 5-HT2A receptor agonists might prove to be safe and rapidly acting antidepressants. Finally, we examine understudied and orphan GPCRs using the MRGPR family of receptors as an example.
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Affiliation(s)
- Gavin P Schmitz
- Department of Pharmacology, UNC Chapel Hill Medical School, Chapel Hill, North Carolina, United States
| | - Bryan L Roth
- Department of Pharmacology, UNC Chapel Hill Medical School, Chapel Hill, North Carolina, United States
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4
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Rische CH, Thames AN, Krier-Burris RA, O’Sullivan JA, Bochner BS, Scott EA. Drug delivery targets and strategies to address mast cell diseases. Expert Opin Drug Deliv 2023; 20:205-222. [PMID: 36629456 PMCID: PMC9928520 DOI: 10.1080/17425247.2023.2166926] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 11/10/2022] [Accepted: 01/06/2023] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Current and developing mast cell therapeutics are reliant on small molecule drugs and biologics, but few are truly selective for mast cells. Most have cellular and disease-specific limitations that require innovation to overcome longstanding challenges to selectively targeting and modulating mast cell behavior. This review is designed to serve as a frame of reference for new approaches that utilize nanotechnology or combine different drugs to increase mast cell selectivity and therapeutic efficacy. AREAS COVERED Mast cell diseases include allergy and related conditions as well as malignancies. Here, we discuss the targets of existing and developing therapies used to treat these disease pathologies, classifying them into cell surface, intracellular, and extracellular categories. For each target discussed, we discuss drugs that are either the current standard of care, under development, or have indications for potential use. Finally, we discuss how novel technologies and tools can be used to take existing therapeutics to a new level of selectivity and potency against mast cells. EXPERT OPINION There are many broadly and very few selectively targeted therapeutics for mast cells in allergy and malignant disease. Combining existing targeting strategies with technology like nanoparticles will provide novel platforms to treat mast cell disease more selectively.
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Affiliation(s)
- Clayton H. Rische
- Northwestern University McCormick School of Engineering, Department of Biomedical Engineering, Evanston, IL, USA
- Northwestern University Feinberg School of Medicine, Division of Allergy and Immunology, Chicago, IL, USA
| | - Ariel N. Thames
- Northwestern University Feinberg School of Medicine, Division of Allergy and Immunology, Chicago, IL, USA
- Northwestern University McCormick School of Engineering, Department of Chemical and Biological Engineering, Evanston, IL, USA
| | - Rebecca A. Krier-Burris
- Northwestern University Feinberg School of Medicine, Division of Allergy and Immunology, Chicago, IL, USA
| | - Jeremy A. O’Sullivan
- Northwestern University Feinberg School of Medicine, Division of Allergy and Immunology, Chicago, IL, USA
| | - Bruce S. Bochner
- Northwestern University Feinberg School of Medicine, Division of Allergy and Immunology, Chicago, IL, USA
| | - Evan A. Scott
- Northwestern University McCormick School of Engineering, Department of Biomedical Engineering, Evanston, IL, USA
- Northwestern University Feinberg School of Medicine, Department of Microbiolgy-Immunology, Chicago, IL, USA
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5
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Toscano A, Elst J, Van Gasse AL, Beyens M, van der Poorten ML, Bridts CH, Mertens C, Van Houdt M, Hagendorens MM, Van Remoortel S, Timmermans JP, Ebo DG, Sabato V. Mas-related G protein-coupled receptor MRGPRX2 in human basophils: Expression and functional studies. Front Immunol 2023; 13:1026304. [PMID: 36726977 PMCID: PMC9885256 DOI: 10.3389/fimmu.2022.1026304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 12/30/2022] [Indexed: 01/18/2023] Open
Abstract
Background Occupancy of MRGPRX2 heralds a new era in our understandings of immediate drug hypersensitivity reactions (IDHRs), but a constitutive expression of this receptor by basophils is debated. Objective To explore the expression and functionality of MRGPRX2 in and on basophils. Methods Basophils from patients with birch pollen allergy, IDHRs to moxifloxacin, and healthy controls were studied in different conditions, that is, in rest, after stimulation with anti-IgE, recombinant major birch pollen allergen (rBet v 1), moxifloxacin, fMLP, substance P (SP), or other potential basophil secretagogues. In a separate set of experiments, basophils were studied after purification and resuspension in different media. Results Resting whole blood basophils barely express MRGPRX2 on their surface and are unresponsive to SP or moxifloxacin. However, surface MRGPRX2 is quickly upregulated upon incubation with anti-IgE or fMLP. Pre-stimulation with anti-IgE can induce a synergic effect on basophil degranulation in IgE-responsive subjects after incubation with SP or moxifloxacin, provided that basophils have been obtained from patients who experienced an IDHR to moxifloxacin. Cell purification can trigger a "spontaneous" and functional upregulation of MRGPRX2 on basophils, not seen in whole blood cells, and its surface density can be influenced by distinct culture media. Conclusion Basophils barely express MRGPRX2 in resting conditions. However, the receptor can be quickly upregulated after stimulation with anti-IgE, fMLP, or after purification, making cells responsive to MRGPRX2 occupation. We anticipate that such "conditioned" basophils constitute a model to explore MRGPRX2 agonism or antagonism, including IDHRs originating from the occupation of this receptor.
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Affiliation(s)
- Alessandro Toscano
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium,Post-Graduate School of Allergology and Clinical Immunology, University of Milan, Milan, Italy
| | - Jessy Elst
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium
| | - Athina L. Van Gasse
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium,Department of Pediatrics and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Pediatrics, Antwerp University Hospital, Antwerp, Belgium
| | - Michiel Beyens
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium
| | - Marie-Line van der Poorten
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium,Department of Pediatrics and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Pediatrics, Antwerp University Hospital, Antwerp, Belgium
| | - Chris H. Bridts
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium
| | - Christel Mertens
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium
| | - Michel Van Houdt
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium
| | - Margo M. Hagendorens
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium,Department of Pediatrics and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Pediatrics, Antwerp University Hospital, Antwerp, Belgium
| | - Samuel Van Remoortel
- Laboratory of Cell Biology and Histology, Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Antwerp, Belgium
| | - Jean-Pierre Timmermans
- Laboratory of Cell Biology and Histology, Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Antwerp, Belgium
| | - Didier G. Ebo
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium,Algemeen Ziekenhuis (AZ) Jan Palfijn Gent, Department of Immunology and Allergology, Ghent, Belgium,*Correspondence: Didier G. Ebo,
| | - Vito Sabato
- Department of Immunology, Allergology, Rheumatology and the Infla-Med Centre of Excellence, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium,Immunology, Allergology, Rheumatology, Antwerp University Hospital, Antwerp, Belgium,Algemeen Ziekenhuis (AZ) Jan Palfijn Gent, Department of Immunology and Allergology, Ghent, Belgium
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Bawazir M, Amponnawarat A, Hui Y, Oskeritzian CA, Ali H. Inhibition of MRGPRX2 but not FcεRI or MrgprB2-mediated mast cell degranulation by a small molecule inverse receptor agonist. Front Immunol 2022; 13:1033794. [PMID: 36275683 PMCID: PMC9582160 DOI: 10.3389/fimmu.2022.1033794] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 09/16/2022] [Indexed: 11/17/2022] Open
Abstract
Mas-related G protein-coupled receptor-X2 (MRGPRX2) expressed on mast cells (MCs) contributes to hypersensitivity reactions to cationic US-Food and Drug Administration (FDA) approved drugs such as the neuromuscular blocking agent, rocuronium. In addition, activation of MRGPRX2 by the neuropeptide substance P (SP) and the pro-adrenomedullin peptide (PAMP-12) is associated with a variety of cutaneous conditions such as neurogenic inflammation, pain, atopic dermatitis, urticaria, and itch. Thus, small molecules aimed at blocking MRGPRX2 constitute potential options for modulating IgE-independent MC-mediated disorders. Two inverse MRGPRX2 agonists, named C9 and C9-6, have recently been identified, which inhibit basal G protein activation and agonist-induced calcium mobilization in transfected HEK293 cells. Substance P serves as a balanced agonist for MRGPRX2 whereby it activates both G protein-mediated degranulation and β-arrestin-mediated receptor internalization. The purpose of this study was to determine if C9 blocks MRGPRX2's G protein and β-arrestin-mediated signaling and to determine its specificity. We found that C9, but not its inactive analog C7, inhibited degranulation in RBL-2H3 cells stably expressing MRGPRX2 in response to SP, PAMP-12 and rocuronium with an IC50 value of ~300 nM. C9 also inhibited degranulation as measured by cell surface expression of CD63, CD107a and β-hexosaminidase release in LAD2 cells and human skin-derived MCs in response to SP but not the anaphylatoxin, C3a or FcϵRI-aggregation. Furthermore, C9 inhibited β-arrestin recruitment and MRGPRX2 internalization in response to SP and PAMP-12. We found that a G protein-coupling defective missense MRGPRX2 variant (V282M) displays constitutive activity for β-arrestin recruitment, and that this response was significantly inhibited by C9. Rocuronium, SP and PAMP-12 caused degranulation in mouse peritoneal MCs and these responses were abolished in the absence of MrgprB2 or cells treated with pertussis toxin but C9 had no effect. These findings suggest that C9 could provide an important framework for developing novel therapeutic approaches for the treatment of IgE-independent MC-mediated drug hypersensitivity and cutaneous disorders.
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Affiliation(s)
- Maram Bawazir
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Oral Diagnostic Sciences, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Aetas Amponnawarat
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Family and Community Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Yvonne Hui
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, United States
| | - Carole A. Oskeritzian
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, United States
| | - Hydar Ali
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
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7
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MAS-related G protein-coupled receptors X (MRGPRX): Orphan GPCRs with potential as targets for future drugs. Pharmacol Ther 2022; 238:108259. [DOI: 10.1016/j.pharmthera.2022.108259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/30/2022] [Accepted: 08/01/2022] [Indexed: 11/20/2022]
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Llorián-Salvador M, Byrne EM, Szczepan M, Little K, Chen M, Xu H. Complement activation contributes to subretinal fibrosis through the induction of epithelial-to-mesenchymal transition (EMT) in retinal pigment epithelial cells. J Neuroinflammation 2022; 19:182. [PMID: 35831910 PMCID: PMC9447479 DOI: 10.1186/s12974-022-02546-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 06/22/2022] [Indexed: 11/16/2022] Open
Abstract
Background We previously reported higher plasma levels of complement fragments C3a and C5a in neovascular Age-related Macular Degeneration (nAMD) patients with macular fibrosis. This study aimed to understand whether complement activation contributes to the development of macular fibrosis and the underlying mechanisms involved. Methods Complement activation was blocked using a C5 neutralizing antibody (BB5.1) in C57BL/6J mice after induction of subretinal fibrosis using the two-stage laser protocol. Fibrotic lesions were examined 10 days after the 2nd laser through fundus examination and immunohistochemistry. The expression of C5aR in fibrotic lesions and retinal pigment epithelial (RPE) cultures were examined by confocal microscopy. Primary murine RPE cells were treated with C3a or C5a (10–100 ng/mL) or TGF-β2 (10 ng/mL). Epithelial-to-mesenchymal transition (EMT) was assessed through various readouts. The expression of E-cadherin, vimentin, fibronectin, α-SMA, Slug, ERK/AKT and pSMAD2/3 were determined by Western blot and immunocytochemistry. Collagen contraction and wound-healing assays were used as functional readouts of EMT. The production of IL-6, TGF-β1, TGF-β2 and VEGF by RPE cells were determined by ELISA. PMX53 was used to block C5aR in RPE cultures and in vivo in mice with subretinal fibrosis. Results Extensive C5b-9 deposition was detected at the site of subretinal fibrosis. BB5.1 treatment completely abrogated complement activation and significantly reduced subretinal fibrosis. C5aR was detected in RPE and infiltrating MHC-II+ cells in subretinal fibrosis. In vitro, RPE cells constitutively express C5/C5a and C5aR, and their expression was increased by TGF-β2 treatment. C5a but not C3a increased fibronectin, α-SMA, vimentin and Slug expression, and decreased E-cadherin expression in RPE cells. C5a treatment also increased the contractility and migration of RPE cells and enhanced the production of VEGF and TGF-β1/2. C5a treatment induced pSmad2/3 and pERK1/2 expression in RPE cells and this was blocked by PMX53. PMX53 treatment significantly reduced sodium fluorescein leakage in the subretinal fibrosis model, while collagen-I+ lesions only mildly reduced. Conclusions Complement activation is critically involved in the development of subretinal fibrosis, partially through C5a–C5aR-mediated EMT in RPE cells. Targeting complement activation rather than C5a may be a novel approach for the management of macular fibrosis. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02546-3.
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Affiliation(s)
- María Llorián-Salvador
- The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK.,Vall d´Hebron Research Institute (VHIR), Universitat Autonòma de Barcelona, 08035, Barcelona, Spain
| | - Eimear M Byrne
- The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK.,Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003, Barcelona, Spain
| | - Manon Szczepan
- The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK
| | - Karis Little
- The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK
| | - Mei Chen
- The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK
| | - Heping Xu
- The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland, UK.
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Lazki-Hagenbach P, Kleeblatt E, Ali H, Sagi-Eisenberg R. Spatiotemporal Patterns of Substance P-Bound MRGPRX2 Reveal a Novel Connection Between Macropinosome Resolution and Secretory Granule Regeneration in Mast Cells. Front Immunol 2022; 13:892239. [PMID: 35837385 PMCID: PMC9273857 DOI: 10.3389/fimmu.2022.892239] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 05/30/2022] [Indexed: 12/02/2022] Open
Abstract
MRGPRX2, the human member of the MAS-related G protein coupled receptors (Mrgprs), serves as the cellular target of human mast cells (MCs) for innate ligands, including neuropeptides and antimicrobial peptides. In addition, MRGPRX2 also functions as the receptor for multiple FDA-approved drugs. As such, MRGPRX2 is a mediator of MC responses in neurogenic inflammation, host defense and pseudoallergy. We analyzed the spatiotemporal patterns of MRGPRX2 following its binding of the neuropeptide substance P (SP). Herein, we show that MRGPRX2 internalizes via both endocytosis and macropinocytosis, followed by its distribution between a perinuclear region and the secretory granules (SGs). Further, we show that MRGPRX2-containing macropinosomes undergo resolution by a mechanism that involves dynamin and LC3, giving rise to the incorporation of both LC3 and MRGPRX2 into the SGs. SP then promotes the acidification of the LC3-associated SGs, presumably by stimulating their fusion with lysosomes. Taken together, our results reveal a unique mode of MRGPRX2 trafficking that complements endocytosis and involves macropinocytosis, autophagic machinery-assisted macropinosome resolution and receptor delivery to the SGs.
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Affiliation(s)
- Pia Lazki-Hagenbach
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Elisabeth Kleeblatt
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Hydar Ali
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ronit Sagi-Eisenberg
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
- *Correspondence: Ronit Sagi-Eisenberg,
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10
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Mas-Related G Protein-Coupled Receptors (Mrgprs) as Mediators of Gut Neuro-Immune Signaling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1383:259-269. [PMID: 36587165 DOI: 10.1007/978-3-031-05843-1_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Over the past 15 years, the research field on Mas-related G protein-coupled receptors (Mrgprs), a relatively new family of rhodopsin A-like G protein-coupled receptors, has expanded enormously, and a plethora of recent studies have provided evidence that several of these Mrgpr family members play an important role in the underlying mechanisms of itch and pain, as well as in the initiation and modulation of inflammatory/allergic responses. Initial studies mainly focused on the skin, but more recently also visceral organs such as the respiratory and gastrointestinal (GI) tracts emerged as sites for Mrgpr involvement. It has become clear that the gastrointestinal tract and its innervation in close association with the immune system represent a novel expression site for Mrgprs where they contribute to the interoceptive mechanisms maintaining homeostasis and might constitute promising targets in chronic abdominal pain disorders. In this short review, we provide an update of our current knowledge on the expression, distribution, and function of members of this Mrgpr family in intrinsic and extrinsic neuro-immune pathways related to the gastrointestinal tract, their mediatory role(s) in gut neuro-immune signaling, and their involvement in visceral afferent (nociceptive) pathways.
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11
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Ligands and Signaling of Mas-Related G Protein-Coupled Receptor-X2 in Mast Cell Activation. Rev Physiol Biochem Pharmacol 2021; 179:139-188. [PMID: 33479839 DOI: 10.1007/112_2020_53] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Mas-related G protein-coupled receptor-X2 (MRGPRX2) is known as a novel receptor to activate mast cells (MCs). MRGPRX2 plays a dual role in promoting MC-dependent host defense and immunomodulation and contributing to the pathogenesis of pseudo-allergic drug reactions, pain, itching, and inflammatory diseases. In this article, we discuss the possible signaling pathways of MCs activation mediated by MRGPRX2 and summarize and classify agonists and inhibitors of MRGPRX2 in MCs activation. MRGPRX2 is a low-affinity and low-selectivity receptor, which allows it to interact with a diverse group of ligands. Diverse MRGPRX2 ligands utilize conserved residues in its transmembrane (TM) domains and carboxyl-terminus Ser/Thr residues to undergo ligand binding and G protein coupling. The coupling likely initiates phosphorylation cascades, induces Ca2+ mobilization, and causes degranulation and generation of cytokines and chemokines via MAPK and NF-κB pathways, resulting in MCs activation. Agonists of MRGPRX2 on MCs are divided into peptides (including antimicrobial peptides, neuropeptides, MC degranulating peptides, peptide hormones) and nonpeptides (including FDA-approved drugs). Inhibitors of MRGPRX2 include non-selective GPCR inhibitors, herbal extracts, small-molecule MRGPRX2 antagonists, and DNA aptamer drugs. Screening and classifying MRGPRX2 ligands and summarizing their signaling pathways would improve our understanding of MRGPRX2-mediated physiological and pathological effects on MCs.
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12
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Substance P Serves as a Balanced Agonist for MRGPRX2 and a Single Tyrosine Residue Is Required for β-Arrestin Recruitment and Receptor Internalization. Int J Mol Sci 2021; 22:ijms22105318. [PMID: 34070125 PMCID: PMC8158387 DOI: 10.3390/ijms22105318] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/14/2021] [Accepted: 05/15/2021] [Indexed: 12/13/2022] Open
Abstract
The neuropeptide substance P (SP) mediates neurogenic inflammation and pain and contributes to atopic dermatitis in mice through the activation of mast cells (MCs) via Mas-related G protein-coupled receptor (GPCR)-B2 (MrgprB2, human ortholog MRGPRX2). In addition to G proteins, certain MRGPRX2 agonists activate an additional signaling pathway that involves the recruitment of β-arrestins, which contributes to receptor internalization and desensitization (balanced agonists). We found that SP caused β-arrestin recruitment, MRGPRX2 internalization, and desensitization. These responses were independent of G proteins, indicating that SP serves as a balanced agonist for MRGPRX2. A tyrosine residue in the highly conserved NPxxY motif contributes to the activation and internalization of many GPCRs. We have previously shown that Tyr279 of MRGPRX2 is essential for G protein-mediated signaling and degranulation. To assess its role in β-arrestin-mediated MRGPRX2 regulation, we replaced Tyr279 in the NPxxY motif of MRGPRX2 with Ala (Y279A). Surprisingly, we found that, unlike the wild-type receptor, Y279A mutant of MRGPRX2 was resistant to SP-induced β-arrestin recruitment and internalization. This study reveals the novel findings that activation of MRGPRX2 by SP is regulated by β-arrestins and that a highly conserved tyrosine residue within MRGPRX2’s NPxxY motif contributes to both G protein- and β-arrestin-mediated responses.
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13
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Unlocking the Non-IgE-Mediated Pseudo-Allergic Reaction Puzzle with Mas-Related G-Protein Coupled Receptor Member X2 (MRGPRX2). Cells 2021; 10:cells10051033. [PMID: 33925682 PMCID: PMC8146469 DOI: 10.3390/cells10051033] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 04/19/2021] [Accepted: 04/25/2021] [Indexed: 12/17/2022] Open
Abstract
Mas-related G-protein coupled receptor member X2 (MRGPRX2) is a class A GPCR expressed on mast cells. Mast cells are granulated tissue-resident cells known for host cell response, allergic response, and vascular homeostasis. Immunoglobulin E receptor (FcεRI)-mediated mast cell activation is a well-studied and recognized mechanism of allergy and hypersensitivity reactions. However, non-IgE-mediated mast cell activation is less explored and is not well recognized. After decades of uncertainty, MRGPRX2 was discovered as the receptor responsible for non-IgE-mediated mast cells activation. The puzzle of non-IgE-mediated pseudo-allergic reaction is unlocked by MRGPRX2, evidenced by a plethora of reported endogenous and exogenous MRGPRX2 agonists. MRGPRX2 is exclusively expressed on mast cells and exhibits varying affinity for many molecules such as antimicrobial host defense peptides, neuropeptides, and even US Food and Drug Administration-approved drugs. The discovery of MRGPRX2 has changed our understanding of mast cell biology and filled the missing link of the underlying mechanism of drug-induced MC degranulation and pseudo-allergic reactions. These non-canonical characteristics render MRGPRX2 an intriguing player in allergic diseases. In the present article, we reviewed the emerging role of MRGPRX2 as a non-IgE-mediated mechanism of mast cell activation in pseudo-allergic reactions. We have presented an overview of mast cells, their receptors, structural insight into MRGPRX2, MRGPRX2 agonists and antagonists, the crucial role of MRGPRX2 in pseudo-allergic reactions, current challenges, and the future research direction.
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14
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Klein A, Solinski HJ, Malewicz NM, Ieong HFH, Sypek EI, Shimada SG, Hartke TV, Wooten M, Wu G, Dong X, Hoon MA, LaMotte RH, Ringkamp M. Pruriception and neuronal coding in nociceptor subtypes in human and nonhuman primates. eLife 2021; 10:64506. [PMID: 33891544 PMCID: PMC8064749 DOI: 10.7554/elife.64506] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 04/12/2021] [Indexed: 12/11/2022] Open
Abstract
In humans, intradermal administration of β-alanine (ALA) and bovine adrenal medulla peptide 8–22 (BAM8-22) evokes the sensation of itch. Currently, it is unknown which human dorsal root ganglion (DRG) neurons express the receptors of these pruritogens, MRGPRD and MRGPRX1, respectively, and which cutaneous afferents these pruritogens activate in primate. In situ hybridization studies revealed that MRGPRD and MRGPRX1 are co-expressed in a subpopulation of TRPV1+ human DRG neurons. In electrophysiological recordings in nonhuman primates (Macaca nemestrina), subtypes of polymodal C-fiber nociceptors are preferentially activated by ALA and BAM8-22, with significant overlap. When pruritogens ALA, BAM8-22, and histamine, which activate different subclasses of C-fiber afferents, are administered in combination, human volunteers report itch and nociceptive sensations similar to those induced by a single pruritogen. Our results provide evidence for differences in pruriceptive processing between primates and rodents, and do not support the spatial contrast theory of coding of itch and pain.
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Affiliation(s)
- Amanda Klein
- Department of Neurosurgery, Neurosurgery Pain Research Institute, School of Medicine, Johns Hopkins University, Baltimore, United States.,Department of Pharmacy Practice and Pharmaceutical Sciences, University of Minnesota, Duluth, United States
| | - Hans Jürgen Solinski
- Molecular Genetics Section, National Institute of Dental and Craniofacial Research, Bethesda, United States.,Department of Experimental Pain Research, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Nathalie M Malewicz
- Department of Anesthesiology, School of Medicine, Yale University, New Haven, United States.,Department of Anesthesiology, Intensive Care Medicine and Pain Management, Medical Faculty of Ruhr-University Bochum, BG University Hospital Bergmannsheil, Bochum, Germany
| | - Hada Fong-Ha Ieong
- Department of Anesthesiology, School of Medicine, Yale University, New Haven, United States
| | - Elizabeth I Sypek
- The Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Steven G Shimada
- Department of Anesthesiology, School of Medicine, Yale University, New Haven, United States
| | - Timothy V Hartke
- Department of Neurosurgery, Neurosurgery Pain Research Institute, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Matthew Wooten
- Department of Neurosurgery, Neurosurgery Pain Research Institute, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Gang Wu
- Department of Neurosurgery, Neurosurgery Pain Research Institute, School of Medicine, Johns Hopkins University, Baltimore, United States
| | - Xinzhong Dong
- The Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Mark A Hoon
- Molecular Genetics Section, National Institute of Dental and Craniofacial Research, Bethesda, United States
| | - Robert H LaMotte
- Department of Anesthesiology, School of Medicine, Yale University, New Haven, United States
| | - Matthias Ringkamp
- Department of Neurosurgery, Neurosurgery Pain Research Institute, School of Medicine, Johns Hopkins University, Baltimore, United States
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15
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Hermans MAW, van Stigt AC, van de Meerendonk S, Schrijver B, van Daele PLA, van Hagen PM, van Splunter M, Dik WA. Human Mast Cell Line HMC1 Expresses Functional Mas-Related G-Protein Coupled Receptor 2. Front Immunol 2021; 12:625284. [PMID: 33790895 PMCID: PMC8006456 DOI: 10.3389/fimmu.2021.625284] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/01/2021] [Indexed: 12/14/2022] Open
Abstract
The Mas-related G-protein-coupled receptor X2 (MRGPRX2) is prominently expressed by mast cells and induces degranulation upon binding by different ligands. Its activation has been linked to various mast cell-related diseases, such as chronic spontaneous urticaria, atopic dermatitis and asthma. Therefore, inhibition of MRGPRX2 activity represents a therapeutic target for these conditions. However, the exact pathophysiology of this receptor is still unknown. In vitro research with mast cells is often hampered by the technical limitations of available cell lines. The human mast cell types LAD2 and HuMC (human mast cells cultured from CD34+ progenitor cells) most closely resemble mature human mast cells, yet have a very slow growth rate. A fast proliferating alternative is the human mast cell line HMC1, but they are considered unsuitable for degranulation assays due to their immature phenotype. Moreover, the expression and functionality of MRGPRX2 on HMC1 is controversial. Here, we describe the MRGPRX2 expression and functionality in HMC1 cells, and compare these with LAD2 and HuMC. We also propose a model to render HMC1 suitable for degranulation assays by pre-incubating them with latrunculin-B (Lat-B). Expression of MRGPRX2 by HMC1 was proven by RQ-PCR and flowcytometry, although at lower levels compared with LAD2 and HuMC. Pre-incubation of HMC1 cells with Lat-B significantly increased the overall degranulation capacity, without significantly changing their MRGPRX2 expression, phenotype or morphology. The MRGPRX2 specific compound 48/80 (C48/80) effectively induced degranulation of HMC1 as measured by CD63 membrane expression and β-hexosaminidase release, albeit in lower levels than for LAD2 or HuMC. HMC1, LAD2 and HuMC each had different degranulation kinetics upon stimulation with C48/80. Incubation with the MRGPRX2 specific inhibitor QWF inhibited C48/80-induced degranulation, confirming the functionality of MRGPRX2 on HMC1. In conclusion, HMC1 cells have lower levels of MRGPRX2 expression than LAD2 or HuMC, but are attractive for in vitro research because of their high growth rate and stable phenotype. HMC1 can be used to study MRGPRX2-mediated degranulation after pre-incubation with Lat-B, which provides the opportunity to explore MPRGRX2 biology in mast cells in a feasible way.
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Affiliation(s)
- Maud A W Hermans
- Section of Allergy & Immunology, Department of Internal Medicine, Erasmus MC, Rotterdam, Netherlands
| | - Astrid C van Stigt
- Laboratory of Medical Immunology, Department of Immunology, Erasmus MC, Rotterdam, Netherlands
| | - Sanne van de Meerendonk
- Laboratory of Medical Immunology, Department of Immunology, Erasmus MC, Rotterdam, Netherlands
| | - Benjamin Schrijver
- Laboratory of Medical Immunology, Department of Immunology, Erasmus MC, Rotterdam, Netherlands
| | - Paul L A van Daele
- Section of Allergy & Immunology, Department of Internal Medicine, Erasmus MC, Rotterdam, Netherlands.,Laboratory of Medical Immunology, Department of Immunology, Erasmus MC, Rotterdam, Netherlands
| | - Petrus M van Hagen
- Section of Allergy & Immunology, Department of Internal Medicine, Erasmus MC, Rotterdam, Netherlands.,Laboratory of Medical Immunology, Department of Immunology, Erasmus MC, Rotterdam, Netherlands
| | - Marloes van Splunter
- Section of Allergy & Immunology, Department of Internal Medicine, Erasmus MC, Rotterdam, Netherlands
| | - Willem A Dik
- Section of Allergy & Immunology, Department of Internal Medicine, Erasmus MC, Rotterdam, Netherlands.,Laboratory of Medical Immunology, Department of Immunology, Erasmus MC, Rotterdam, Netherlands
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16
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A group of cationic amphiphilic drugs activates MRGPRX2 and induces scratching behavior in mice. J Allergy Clin Immunol 2021; 148:506-522.e8. [PMID: 33617860 DOI: 10.1016/j.jaci.2020.12.655] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 11/10/2020] [Accepted: 12/28/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Mas gene-related G protein-coupled receptors (MRGPRs) are a G protein-coupled receptor family responsive to various exogenous and endogenous agonists, playing a fundamental role in pain and itch sensation. The primate-specific family member MRGPRX2 and its murine orthologue MRGPRB2 are expressed by mast cells mediating IgE-independent signaling and pseudoallergic drug reactions. OBJECTIVES Our aim was to increase knowledge about the function and regulation of MRGPRX2/MRGPRB2, which is of major importance in prevention of drug hypersensitivity reactions and drug-induced pruritus. METHODS To identify novel MRGPR (ant)agonists, we screened a library of pharmacologically active compounds by utilizing a high-throughput calcium mobilization assay. The identified hit compounds were analyzed for their pseudoallergic and pruritogenic effects in mice and human. RESULTS We found a class of commonly used drugs activating MRGPRX2 that, to a large extent, consists of antidepressants, antiallergic drugs, and antipsychotics. Three-dimensional pharmacophore modeling revealed structural similarities of the identified agonists, classifying them as cationic amphiphilic drugs. Mast cell activation was investigated by using the 3 representatively selected antidepressants clomipramine, paroxetine, and desipramine. Indeed, we were able to show a concentration-dependent activation and MRGPRX2-dependent degranulation of the human mast cell line LAD2 (Laboratory of Allergic Diseases-2). Furthermore, clomipramine, paroxetine, and desipramine were able to induce degranulation of human skin and murine peritoneal mast cells. These substances elicited dose-dependent scratching behavior following intradermal injection into C57BL/6 mice but less so in MRGPRB2-mutant mice, as well as wheal-and-flare reactions following intradermal injections in humans. CONCLUSION Our results contribute to the characterization of structure-activity relationships and functionality of MRGPRX2 ligands and facilitate prediction of adverse reactions such as drug-induced pruritus to prevent severe drug hypersensitivity reactions.
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17
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Serhan N, Cenac N, Basso L, Gaudenzio N. Mas-related G protein-coupled receptors (Mrgprs) - Key regulators of neuroimmune interactions. Neurosci Lett 2021; 749:135724. [PMID: 33600909 DOI: 10.1016/j.neulet.2021.135724] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 02/03/2021] [Accepted: 02/05/2021] [Indexed: 02/06/2023]
Abstract
Interplay between physiological systems in the body plays a prominent role in health and disease. At the cellular level, such interplay is orchestrated through the binding of specific ligands to their receptors expressed on cell surface. G protein-coupled receptors (GPCR) are seven-transmembrane domain receptors that initiate various cellular responses and regulate homeostasis. In this review, we focus on particular GPCRs named Mas-related G protein-coupled receptors (Mrgprs) mainly expressed by sensory neurons and specialized immune cells. We describe the different subfamilies of Mrgprs and their specific ligands, as well as recent advances in the field that illustrate the role played by these receptors in neuro-immune biological processes, including itch, pain and inflammation in diverse organs.
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Affiliation(s)
- Nadine Serhan
- Toulouse Institute for Infectious and Inflammatory Diseases, INSERM UMR1291, CNRS UMR5051, University of Toulouse III, Toulouse, France
| | - Nicolas Cenac
- IRSD, Université de Toulouse, INSERM, INRA, INP-ENVT, Université de Toulouse 3 Paul Sabatier, Toulouse, France
| | - Lilian Basso
- Toulouse Institute for Infectious and Inflammatory Diseases, INSERM UMR1291, CNRS UMR5051, University of Toulouse III, Toulouse, France.
| | - Nicolas Gaudenzio
- Toulouse Institute for Infectious and Inflammatory Diseases, INSERM UMR1291, CNRS UMR5051, University of Toulouse III, Toulouse, France.
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18
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Authentic and Ectopically Expressed MRGPRX2 Elicit Similar Mechanisms to Stimulate Degranulation of Mast Cells. Cells 2021; 10:cells10020376. [PMID: 33673037 PMCID: PMC7918488 DOI: 10.3390/cells10020376] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/01/2021] [Accepted: 02/09/2021] [Indexed: 12/24/2022] Open
Abstract
The identification of the Mas-related G-protein-coupled receptors (Mrgpr) as targets of diverse stimuli of mast cells (MCs), including neuropeptides and pseudo-allergy causing drugs, has placed these receptors at a prime position in MC research. However, the species-dependent diversity of these receptors raises the need for an adequate model for investigating the human MRGPRX2 receptor. RBL-2H3 cells, stably transfected with MRGPRX2 (RBL-MRGPRX2), are increasingly used for this purpose. Therefore, we investigated whether ectopically expressed MRGPRX2, in rat MCs, recapitulates its authentic signaling. To this purpose, we performed a broad comparative study of the responses of human LAD-2 MCs that express MRGPRX2 endogenously, and RBL-MRGPRX2 cells to compound 48/80, substance P and vancomycin, three proto-type ligands of MRGPRX2. We demonstrate that both models share similar dose-response relationships, kinetics and sensitivities to a wide range of signaling targeting drugs. Therefore, our results indicate that ectopically expressed MRGPRX2 preserves the signaling pathways employed to evoke human MC degranulation, which we show to rely on ERK1/2 MAP kinases, phospholipase C (PLC) and autophagy-related signaling. Importantly, we also show that the underlying mechanisms of MRGPRX2-triggered MC degranulation in either LAD-2 or RBL-MRGPRX2 cells are different from those elicited by its rodent orthologs.
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19
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Chompunud Na Ayudhya C, Amponnawarat A, Roy S, Oskeritzian CA, Ali H. MRGPRX2 Activation by Rocuronium: Insights from Studies with Human Skin Mast Cells and Missense Variants. Cells 2021; 10:156. [PMID: 33467419 PMCID: PMC7830812 DOI: 10.3390/cells10010156] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/17/2022] Open
Abstract
Perioperative hypersensitivity (POH) to the neuromuscular blocking drug (NMBD) rocuronium was previously thought to be IgE and mast cell (MC)-mediated. However, the recent seminal observation that rocuronium induces degranulation in murine peritoneal MCs (PMCs) via Mas-related G protein-coupled receptor B2 (MrgprB2) led to the idea that POH to this drug involves the activation of MRGPRX2 (human ortholog of MrgprB2). Furthermore, based on the demonstration that a patient with POH to rocuronium displayed three missense mutations (M196I, L226P and L237P) in MRGPRX2's transmembrane domains, it was proposed that this hypersensitivity reaction resulted from aberrant activation of this receptor. We found that rocuronium at 20 µg/mL caused degranulation in mouse PMCs via MrgprB2 but required at least 500 µg/mL to induce degranulation in human MCs via MRGPRX2. Furthermore, RBL-2H3 cells transiently expressing M196I, L226P and L237P variants did not display enhanced degranulation in response to rocuronium when compared to the wild-type receptor. These findings provide the first demonstration that rocuronium induces degranulation in human MCs via MRGPRX2. Furthermore, the important differences between MrgprB2 and MRGPRX2 and the inability of rocuronium to induce enhanced response in cells expressing MRGPRX2 variants suggest that the mechanism of its POH is more complex than previously thought.
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Affiliation(s)
- Chalatip Chompunud Na Ayudhya
- Department of Basic and Translational Sciences, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA; (C.C.N.A.); (A.A.); (S.R.)
| | - Aetas Amponnawarat
- Department of Basic and Translational Sciences, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA; (C.C.N.A.); (A.A.); (S.R.)
| | - Saptarshi Roy
- Department of Basic and Translational Sciences, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA; (C.C.N.A.); (A.A.); (S.R.)
| | - Carole A. Oskeritzian
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC 20209, USA;
| | - Hydar Ali
- Department of Basic and Translational Sciences, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA; (C.C.N.A.); (A.A.); (S.R.)
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20
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Signal Transduction Pathways Activated by Innate Immunity in Mast Cells: Translating Sensing of Changes into Specific Responses. Cells 2020; 9:cells9112411. [PMID: 33158024 PMCID: PMC7693401 DOI: 10.3390/cells9112411] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/21/2020] [Accepted: 10/28/2020] [Indexed: 12/17/2022] Open
Abstract
Mast cells (MCs) constitute an essential cell lineage that participates in innate and adaptive immune responses and whose phenotype and function are influenced by tissue-specific conditions. Their mechanisms of activation in type I hypersensitivity reactions have been the subject of multiple studies, but the signaling pathways behind their activation by innate immunity stimuli are not so well described. Here, we review the recent evidence regarding the main molecular elements and signaling pathways connecting the innate immune receptors and hypoxic microenvironment to cytokine synthesis and the secretion of soluble or exosome-contained mediators in this cell type. When known, the positive and negative control mechanisms of those pathways are presented, together with their possible implications for the understanding of mast cell-driven chronic inflammation. Finally, we discuss the relevance of the knowledge about signaling in this cell type in the recognition of MCs as central elements on innate immunity, whose remarkable plasticity converts them in sensors of micro-environmental discontinuities and controllers of tissue homeostasis.
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21
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Elieh Ali Komi D, Shafaghat F, Kovanen PT, Meri S. Mast cells and complement system: Ancient interactions between components of innate immunity. Allergy 2020; 75:2818-2828. [PMID: 32446274 DOI: 10.1111/all.14413] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 04/09/2020] [Accepted: 04/26/2020] [Indexed: 12/23/2022]
Abstract
The emergence and evolution of the complement system and mast cells (MCs) can be traced back to sea urchins and the ascidian Styela plicata, respectively. Acting as a cascade of enzymatic reactions, complement is activated through the classical (CP), the alternative (AP), and the lectin pathway (LP) based on the recognized molecules. The system's main biological functions include lysis, opsonization, and recruitment of phagocytes. MCs, beyond their classic role as master cells of allergic reactions, play a role in other settings, as well. Thus, MCs are considered as extrahepatic producers of complement proteins. They express various complement receptors, including those for C3a and C5a. C3a and C5a not only activate the C3aR and C5aR expressing MCs but also act as chemoattractants for MCs derived from different anatomic sites, such as from the bone marrow, human umbilical cord blood, or skin in vitro. Cross talk between MCs and complement is facilitated by the production of complement proteins by MCs and their activation by the MC tryptase. The coordinated activity between MCs and the complement system plays a key role, for example, in a number of allergic, cutaneous, and vascular diseases. At a molecular level, MCs and complement system interactions are based on the production of several complement zymogens by MCs and their activation by MC-released proteases. Additionally, at a cellular level, MCs act as potent effector cells of complement activation by expressing receptors for C3a and C5a through which their chemoattraction and activation are mediated by anaphylatoxins in a paracrine and autocrine fashion.
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Affiliation(s)
- Daniel Elieh Ali Komi
- Immunology Research Center Tabriz University of Medical Sciences Tabriz Iran
- Department of Immunology Tabriz University of Medical Sciences Tabriz Iran
| | - Farzaneh Shafaghat
- Immunology Research Center Tabriz University of Medical Sciences Tabriz Iran
- Department of Immunology Tabriz University of Medical Sciences Tabriz Iran
| | | | - Seppo Meri
- Department of Bacteriology and Immunology Immunobiology Research Program University of Helsinki Helsinki Finland
- HUSLAB Helsinki University Central Hospital Helsinki Finland
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22
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Kühn H, Kolkhir P, Babina M, Düll M, Frischbutter S, Fok JS, Jiao Q, Metz M, Scheffel J, Wolf K, Kremer AE, Maurer M. Mas-related G protein-coupled receptor X2 and its activators in dermatologic allergies. J Allergy Clin Immunol 2020; 147:456-469. [PMID: 33071069 DOI: 10.1016/j.jaci.2020.08.027] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 07/28/2020] [Accepted: 08/21/2020] [Indexed: 12/13/2022]
Abstract
The Mas-related G protein-coupled receptor X2 (MRGPRX2) is a multiligand receptor responding to various exogenous and endogenous stimuli. Being highly expressed on skin mast cells, MRGPRX2 triggers their degranulation and release of proinflammatory mediators, and it promotes multicellular signaling cascades, such as itch induction and transmission in sensory neurons. The expression of MRGPRX2 by skin mast cells and the levels of the MRGPRX2 agonists (eg, substance P, major basic protein, eosinophil peroxidase) are upregulated in the serum and/or skin of patients with inflammatory and pruritic skin diseases, such as chronic spontaneous urticaria or atopic dermatitis. Therefore, MRGPRX2 and its agonists might be potential biomarkers for the progression of cutaneous inflammatory diseases and the response to treatment. In addition, they may represent promising targets for prevention and treatment of signs and symptoms in patients with skin diseases or drug reactions. To assess this possibility, this review explores the role and relevance of MRGPRX2 and its activators in cutaneous inflammatory disorders and chronic pruritus.
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Affiliation(s)
- Helen Kühn
- Department of Medicine 1, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Pavel Kolkhir
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany; I.M. Sechenov First Moscow State Medical University (Sechenov University), Division of Immune-mediated Skin Diseases, Moscow, Russia
| | - Magda Babina
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Miriam Düll
- Department of Medicine 1, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Stefan Frischbutter
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Jie Shen Fok
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany; Department of Respiratory Medicine, Box Hill Hospital, Melbourne, Australia; Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia
| | - Qingqing Jiao
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany; Department of Dermatology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Martin Metz
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Jörg Scheffel
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Katharina Wolf
- Department of Medicine 1, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Andreas E Kremer
- Department of Medicine 1, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Marcus Maurer
- Dermatological Allergology, Allergie-Centrum-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
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23
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Karasu E, Demmelmaier J, Kellermann S, Holzmann K, Köhl J, Schmidt CQ, Kalbitz M, Gebhard F, Huber-Lang MS, Halbgebauer R. Complement C5a Induces Pro-inflammatory Microvesicle Shedding in Severely Injured Patients. Front Immunol 2020; 11:1789. [PMID: 32983087 PMCID: PMC7492592 DOI: 10.3389/fimmu.2020.01789] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 07/06/2020] [Indexed: 12/12/2022] Open
Abstract
Initially underestimated as platelet dust, extracellular vesicles are continuously gaining interest in the field of inflammation. Various studies addressing inflammatory diseases have shown that microvesicles (MVs) originating from different cell types are systemic transport vehicles carrying distinct cargoes to modulate immune responses. In this study, we focused on the clinical setting of multiple trauma, which is characterized by activation and dysfunction of both, the fluid-phase and the cellular component of innate immunity. Given the sensitivity of neutrophils for the complement anaphylatoxin C5a, we hypothesized that increased C5a production induces alterations in MV shedding of neutrophils resulting in neutrophil dysfunction that fuels posttraumatic inflammation. In a mono-centered prospective clinical study with polytraumatized patients, we found significantly increased granulocyte-derived MVs containing the C5a receptor (C5aR1, CD88) on their surface. This finding was accompanied by a concomitant loss of C5aR1 on granulocytes indicative of an impaired cellular chemotactic and pro-inflammatory neutrophil functions. Furthermore, in vitro exposure of human neutrophils (from healthy volunteers) to C5a significantly increased MV shedding and C5aR1 loss on neutrophils, which could be blocked using the C5aR1 antagonist PMX53. Mechanistic analyses revealed that the interaction between C5aR1 signaling and the small GTPase Arf6 acts as a molecular switch for MV shedding. When neutrophil derived, C5a-induced MV were exposed to a complex ex vivo whole blood model significant pro-inflammatory properties (NADPH activity, ROS and MPO generation) of the MVs became evident. C5a-induced MVs activated resting neutrophils and significantly induced IL-6 secretion. These data suggest a novel role of the C5a-C5aR1 axis: C5a-induced MV shedding from neutrophils results in decreased C5aR1 surface expression on the one hand, on the other hand it leads to profound inflammatory signals which likely are both key drivers of the neutrophil dysfunction which is regularly observed in patients suffering from multiple traumatic injuries.
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Affiliation(s)
- Ebru Karasu
- Institute of Clinical and Experimental Trauma Immunology, University Hospital Ulm, Ulm, Germany
| | - Julia Demmelmaier
- Institute of Clinical and Experimental Trauma Immunology, University Hospital Ulm, Ulm, Germany
| | - Stephanie Kellermann
- Institute of Clinical and Experimental Trauma Immunology, University Hospital Ulm, Ulm, Germany
| | - Karlheinz Holzmann
- Center for Biomedical Research, Genomics-Core Facility, Ulm University, Ulm, Germany
| | - Jörg Köhl
- Institute for Systemic Inflammation Research (ISEF), University of Lübeck, Lübeck, Germany.,Division of Immunobiology, Cincinnati Children's Hospital, Cincinnati, OH, United States
| | - Christoph Q Schmidt
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, Ulm, Germany
| | - Miriam Kalbitz
- Department of Traumatology, Hand-, Plastic- and Reconstructive Surgery, Center of Surgery, University of Ulm Medical School, Ulm, Germany
| | - Florian Gebhard
- Department of Traumatology, Hand-, Plastic- and Reconstructive Surgery, Center of Surgery, University of Ulm Medical School, Ulm, Germany
| | - Markus S Huber-Lang
- Institute of Clinical and Experimental Trauma Immunology, University Hospital Ulm, Ulm, Germany
| | - Rebecca Halbgebauer
- Institute of Clinical and Experimental Trauma Immunology, University Hospital Ulm, Ulm, Germany
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24
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Wedi B, Gehring M, Kapp A. The pseudoallergen receptor MRGPRX2 on peripheral blood basophils and eosinophils: Expression and function. Allergy 2020; 75:2229-2242. [PMID: 32003863 DOI: 10.1111/all.14213] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 12/17/2019] [Accepted: 12/18/2019] [Indexed: 01/01/2023]
Abstract
BACKGROUND Mas-related G protein-coupled receptor X2 (MRGPRX2) is regarded as a mast cell-specific receptor mediating non-IgE-dependent activation. We aimed to investigate whether human basophils and eosinophils express functional MRGPRX2. METHODS Flow cytometry, immunocytochemistry, immunofluorescence, Western blot, and RT-PCR were performed in highly purified peripheral blood basophils and eosinophils of atopic and nonatopic donors. To assess functional activity, fluorescent avidin-based degranulation assay, calcium mobilization, cytokine production in supernatants, assessment of viability/apoptosis, and tricolor granulocyte activation test were used. RESULTS MRGPRX2 was significantly expressed by basophils and eosinophils but not neutrophils. Functional capacity was shown by anti-MRGPRX2 mAb-induced calcium influx and concentration-dependent induction of degranulation. Sequential stimulation in the calcium mobilization assay gave no evidence for desensitization or receptor internalization. Anti-MRGPRX2 mAb significantly promoted survival. Inhibition of apoptosis could be due to released IL-3, IL-5, and GM-CSF found in supernatants. Short-term incubation with IL-3 dose-dependently upregulated MRGPRX2 expression in both, stimulation for 24 hours with anti-IgE, C5a, fMLP, and IL-3 in basophils and by IL-3, IL-5, and IL-33 in eosinophils. Among known mast cell MRGPRX2 agonists ciprofloxacin but not PMX-53 was functional on basophils and eosinophils. In basophils of allergic subjects, tricolor granulocyte activation test using grass pollen demonstrated MRGPRX2 upregulation associated with degranulation and CD63 expression. CONCLUSION Unraveling the regulation and signaling mechanisms of MRGPRX2 on basophils and eosinophils might enable the development of new therapeutic strategies to prevent or inhibit allergic and nonallergic hypersensitivity. Moreover, addressing MRGPRX2 might have potential for diagnostic purposes in (drug) hypersensitivity.
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Affiliation(s)
- Bettina Wedi
- Department of Dermatology and Allergy Comprehensive Allergy Center Hannover Medical School Hannover Germany
| | - Manuela Gehring
- Department of Dermatology and Allergy Comprehensive Allergy Center Hannover Medical School Hannover Germany
| | - Alexander Kapp
- Department of Dermatology and Allergy Comprehensive Allergy Center Hannover Medical School Hannover Germany
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25
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Rehman A, Baloch NUA, Morrow JP, Pacher P, Haskó G. Targeting of G-protein coupled receptors in sepsis. Pharmacol Ther 2020; 211:107529. [PMID: 32197794 PMCID: PMC7388546 DOI: 10.1016/j.pharmthera.2020.107529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/11/2020] [Accepted: 03/11/2020] [Indexed: 12/11/2022]
Abstract
The Third International Consensus Definitions (Sepsis-3) define sepsis as life-threatening multi-organ dysfunction caused by a dysregulated host response to infection. Sepsis can progress to septic shock-an even more lethal condition associated with profound circulatory, cellular and metabolic abnormalities. Septic shock remains a leading cause of death in intensive care units and carries a mortality of almost 25%. Despite significant advances in our understanding of the pathobiology of sepsis, therapeutic interventions have not translated into tangible differences in the overall outcome for patients. Clinical trials of antagonists of various pro-inflammatory mediators in sepsis have been largely unsuccessful in the past. Given the diverse physiologic roles played by G-protein coupled receptors (GPCR), modulation of GPCR signaling for the treatment of sepsis has also been explored. Traditional pharmacologic approaches have mainly focused on ligands targeting the extracellular domains of GPCR. However, novel techniques aimed at modulating GPCR intracellularly through aptamers, pepducins and intrabodies have opened a fresh avenue of therapeutic possibilities. In this review, we summarize the diverse roles played by various subfamilies of GPCR in the pathogenesis of sepsis and identify potential targets for pharmacotherapy through these novel approaches.
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Affiliation(s)
- Abdul Rehman
- Department of Medicine, Rutgers-New Jersey Medical School, Newark, NJ, United States
| | - Noor Ul-Ain Baloch
- Department of Medicine, Rutgers-New Jersey Medical School, Newark, NJ, United States
| | - John P Morrow
- Department of Medicine, Columbia University, New York City, NY, United States
| | - Pál Pacher
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institutes of Health, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, United States
| | - György Haskó
- Department of Anesthesiology, Columbia University, New York City, NY, United States.
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26
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Callahan BN, Kammala AK, Syed M, Yang C, Occhiuto CJ, Nellutla R, Chumanevich AP, Oskeritzian CA, Das R, Subramanian H. Osthole, a Natural Plant Derivative Inhibits MRGPRX2 Induced Mast Cell Responses. Front Immunol 2020; 11:703. [PMID: 32391014 PMCID: PMC7194083 DOI: 10.3389/fimmu.2020.00703] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 03/30/2020] [Indexed: 12/14/2022] Open
Abstract
Mast cells are tissue-resident innate immune cells known for their prominent role in mediating allergic reactions. MAS-related G-protein coupled receptor-X2 (MRGPRX2) is a promiscuous G-protein coupled receptor (GPCR) expressed on mast cells that is activated by several ligands that share cationic and amphipathic properties. Interestingly, MRGPRX2 ligands include certain FDA-approved drugs, antimicrobial peptides, and neuropeptides. Consequently, this receptor has been implicated in causing mast cell-dependent pseudo-allergic reactions to these drugs and chronic inflammation associated with asthma, urticaria and rosacea in humans. In the current study we examined the role of osthole, a natural plant coumarin, in regulating mast cell responses when activated by the MRGPRX2 ligands, including compound 48/80, the neuropeptide substance P, and the cathelicidin LL-37. We demonstrate that osthole attenuates both the early (Ca2+ mobilization and degranulation) and delayed events (chemokine/cytokine production) of mast cell activation via MRGPRX2 in vitro. Osthole also inhibits MrgprB2- (mouse ortholog of human MRGPRX2) dependent inflammation in in vivo mouse models of pseudo-allergy. Molecular docking analysis suggests that osthole does not compete with the MRGPRX2 ligands for interaction with the receptor, but rather regulates MRGPRX2 activation via allosteric modifications. Furthermore, flow cytometry and confocal microscopy experiments reveal that osthole reduces both surface and intracellular expression levels of MRGPRX2 in mast cells. Collectively, our data demonstrate that osthole inhibits MRGPRX2/MrgprB2-induced mast cell responses and provides a rationale for the use of this natural compound as a safer alternative treatment for pseudo-allergic reactions in humans.
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MESH Headings
- Animals
- Calcium Signaling/drug effects
- Cell Degranulation/drug effects
- Cell Line, Tumor
- Coumarins/administration & dosage
- Disease Models, Animal
- Edema/drug therapy
- Edema/immunology
- Female
- Humans
- Male
- Mast Cells/drug effects
- Mast Cells/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Molecular Docking Simulation
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/chemistry
- Nerve Tissue Proteins/metabolism
- Phytotherapy/methods
- Plant Extracts/administration & dosage
- Rats
- Receptors, G-Protein-Coupled/antagonists & inhibitors
- Receptors, G-Protein-Coupled/chemistry
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Neuropeptide/antagonists & inhibitors
- Receptors, Neuropeptide/chemistry
- Receptors, Neuropeptide/metabolism
- Tissue Donors
- Treatment Outcome
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Affiliation(s)
- Brianna N. Callahan
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Ananth K. Kammala
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Meesum Syed
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Canchai Yang
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | | | - Rithvik Nellutla
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Alena P. Chumanevich
- Department of Pathology, Microbiology, and Immunology, School of Medicine, University of South Carolina, Columbia, SC, United States
| | - Carole A. Oskeritzian
- Department of Pathology, Microbiology, and Immunology, School of Medicine, University of South Carolina, Columbia, SC, United States
| | - Rupali Das
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Hariharan Subramanian
- Department of Physiology, Michigan State University, East Lansing, MI, United States
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27
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Occhiuto CJ, Kammala AK, Yang C, Nellutla R, Garcia M, Gomez G, Subramanian H. Store-Operated Calcium Entry via STIM1 Contributes to MRGPRX2 Induced Mast Cell Functions. Front Immunol 2020; 10:3143. [PMID: 32038646 PMCID: PMC6985555 DOI: 10.3389/fimmu.2019.03143] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Accepted: 12/27/2019] [Indexed: 12/13/2022] Open
Abstract
Mast cells are inflammatory immune cells that play an essential role in mediating allergic reactions in humans. It is well-known that mast cell activation is critically regulated by intracellular calcium ion (Ca2+) concentrations. MAS-related G-protein coupled receptor-X2 (MRGPRX2) is a G-protein coupled receptor (GPCR) expressed on mast cells that is activated by various ligands, including several FDA approved drugs; consequently, this receptor has been implicated in causing pseudo-allergic reactions in humans. MRGPRX2 activation leads to an increase in intracellular Ca2+ levels; however, the Ca2+ mobilizing mechanisms utilized by this receptor are largely unknown. Previous reports showed that store-operated Ca2+ entry (SOCE) via the calcium sensor, stromal interaction molecule 1 (STIM1), regulates mast cell response induced by the high-affinity IgE receptor (FcεRI). In this study, using complementary pharmacologic and genetic ablation approaches we demonstrate that SOCE through STIM1 promotes MRGPRX2-induced human mast cell response in vitro. Importantly, SOCE also critically modulates MrgprB2 (mouse ortholog of human MRGPRX2) dependent inflammation in in vivo mouse models of pseudo-allergy. Collectively, our data suggests that MRGPRX2/MrgprB2 activation of mast cells is dependent on SOCE via STIM1, and further characterization of the MRGPRX2-SOCE-STIM1 pathway will lead to the identification of novel targets for the treatment of pseudo-allergic reactions in humans.
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Affiliation(s)
| | - Ananth K Kammala
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Canchai Yang
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Rithvik Nellutla
- Department of Physiology, Michigan State University, East Lansing, MI, United States
| | - Marco Garcia
- Department of Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC, United States
| | - Gregorio Gomez
- Department of Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC, United States
| | - Hariharan Subramanian
- Department of Physiology, Michigan State University, East Lansing, MI, United States
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28
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Nakashima C, Ishida Y, Kitoh A, Otsuka A, Kabashima K. Interaction of peripheral nerves and mast cells, eosinophils, and basophils in the development of pruritus. Exp Dermatol 2019; 28:1405-1411. [DOI: 10.1111/exd.14014] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 06/29/2019] [Accepted: 07/27/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Chisa Nakashima
- Department of Dermatology Kyoto University Graduate School of Medicine Kyoto Japan
| | - Yoshihiro Ishida
- Department of Dermatology Kyoto University Graduate School of Medicine Kyoto Japan
| | - Akihiko Kitoh
- Department of Dermatology Kyoto University Graduate School of Medicine Kyoto Japan
| | - Atsushi Otsuka
- Department of Dermatology Kyoto University Graduate School of Medicine Kyoto Japan
- Translational Research Department for Skin and Brain Diseases Kyoto University Graduate School of Medicine Kyoto Japan
| | - Kenji Kabashima
- Department of Dermatology Kyoto University Graduate School of Medicine Kyoto Japan
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR) Skin Research Institute of Singapore Biopolis Singapore
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29
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Blake KJ, Jiang XR, Chiu IM. Neuronal Regulation of Immunity in the Skin and Lungs. Trends Neurosci 2019; 42:537-551. [PMID: 31213389 DOI: 10.1016/j.tins.2019.05.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 04/26/2019] [Accepted: 05/16/2019] [Indexed: 02/07/2023]
Abstract
The nervous and immune systems are classically studied as two separate entities. However, their interactions are crucial for maintaining barrier functions at tissues constantly exposed to the external environment. We focus here on the role of neuronal signaling in regulating the immune system at two major barriers: the skin and respiratory tract. Barrier tissues are heavily innervated by sensory and autonomic nerves, and are densely populated by resident immune cells, allowing rapid, coordinated responses to noxious stimuli, as well as to bacterial and fungal pathogens. Neural release of neurotransmitters and neuropeptides allows fast communication with immune cells and their recruitment. In addition to maintaining homeostasis and fighting infections, neuroimmune interactions are also implicated in several chronic inflammatory conditions such as atopic dermatitis (AD), chronic obstructive pulmonary disease (COPD), and asthma.
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Affiliation(s)
- Kimbria J Blake
- Department of Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Xin Ru Jiang
- Department of Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA; Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Isaac M Chiu
- Department of Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA.
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30
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Jia Q, Sun W, Zhang L, Fu J, Lv Y, Lin Y, Han S. Screening the anti‐allergic components in
Saposhnikoviae Radix
using high‐expression Mas‐related G protein‐coupled receptor X2 cell membrane chromatography online coupled with liquid chromatography and mass spectrometry. J Sep Sci 2019; 42:2351-2359. [DOI: 10.1002/jssc.201900114] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/21/2019] [Accepted: 04/27/2019] [Indexed: 01/09/2023]
Affiliation(s)
- Qianqian Jia
- School of PharmacyXi'an Jiaotong University Xi'an P. R. China
| | - Wei Sun
- School of PharmacyXi'an Jiaotong University Xi'an P. R. China
| | - Liyang Zhang
- School of PharmacyXi'an Jiaotong University Xi'an P. R. China
| | - Jia Fu
- School of PharmacyXi'an Jiaotong University Xi'an P. R. China
| | - Yanni Lv
- School of PharmacyXi'an Jiaotong University Xi'an P. R. China
- Department of Pharmaceutical ScienceSchool of PharmacyUniversity of Wisconsin‐Madison Madison WI USA
| | - Yuanyuan Lin
- School of PharmacyXi'an Jiaotong University Xi'an P. R. China
- Department of Pharmaceutical ScienceSchool of PharmacyUniversity of Wisconsin‐Madison Madison WI USA
| | - Shengli Han
- School of PharmacyXi'an Jiaotong University Xi'an P. R. China
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31
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Arifuzzaman M, Mobley YR, Choi HW, Bist P, Salinas CA, Brown ZD, Chen SL, Staats HF, Abraham SN. MRGPR-mediated activation of local mast cells clears cutaneous bacterial infection and protects against reinfection. SCIENCE ADVANCES 2019; 5:eaav0216. [PMID: 30613778 PMCID: PMC6314830 DOI: 10.1126/sciadv.aav0216] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 11/27/2018] [Indexed: 05/22/2023]
Abstract
Mast cells (MCs) are strategically distributed at barrier sites and prestore various immunocyte-recruiting cytokines, making them ideal targets for selective activation to treat peripheral infections. Here, we report that topical treatment with mastoparan, a peptide MC activator (MCA), enhances clearance of Staphylococcus aureus from infected mouse skins and accelerates healing of dermonecrotic lesions. Mastoparan functions by activating connective tissue MCs (CTMCs) via the MRGPRX2 (Mas-related G protein-coupled receptor member X2) receptor. Peripheral CTMC activation, in turn, enhances recruitment of bacteria-clearing neutrophils and wound-healing CD301b+ dendritic cells. Consistent with MCs playing a master coordinating role, MC activation also augmented migration of various antigen-presenting dendritic cells to draining lymph nodes, leading to stronger protection against a second infection challenge. MCAs therefore orchestrate both the innate and adaptive immune arms, which could potentially be applied to combat peripheral infections by a broad range of pathogens.
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Affiliation(s)
- Mohammad Arifuzzaman
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA
| | - Yuvon R. Mobley
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA
| | - Hae Woong Choi
- Department of Pathology, Duke University, Durham, NC 27710, USA
| | - Pradeep Bist
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore
| | | | - Zachary D. Brown
- Undergraduate Program in Biomedical Engineering, Duke University, Durham, NC 27710, USA
| | - Swaine L. Chen
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
- Infectious Diseases Group, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Herman F. Staats
- Department of Pathology, Duke University, Durham, NC 27710, USA
- Department of Immunology, Duke University, Durham, NC 27710, USA
- Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Soman N. Abraham
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA
- Department of Pathology, Duke University, Durham, NC 27710, USA
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore
- Department of Immunology, Duke University, Durham, NC 27710, USA
- Corresponding author.
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32
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Miettinen HM, Gripentrog JM, Lord CI, Nagy JO. CD177-mediated nanoparticle targeting of human and mouse neutrophils. PLoS One 2018; 13:e0200444. [PMID: 29990379 PMCID: PMC6039027 DOI: 10.1371/journal.pone.0200444] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Accepted: 06/26/2018] [Indexed: 12/23/2022] Open
Abstract
Neutrophils are the most abundant white blood cells, with a vital role in innate immune defense against bacterial and fungal pathogens. Although mostly associated with pathological processes directly related to immune defense, they can also play a detrimental role in inflammatory conditions and have been found to have a pro-metastatic role in the spread of cancer cells. Here, we explore ways to temporarily suppress these detrimental activities. We first examined the possibility of using siRNA and antisense oligonucleotides (ASOs) for transient knockdown of the human and mouse C5a receptor, an important chemoattractant receptor involved in neutrophil-mediated injury that is associated with myocardial infarction, sepsis, and neurodegenerative diseases. We found that siRNAs and ASOs transfected into cultured cell lines can eliminate 70–90% of C5a receptor mRNA and protein within 72 h of administration, a clinically relevant time frame after a cardiovascular event. Targeted drug delivery to specific cells or tissues of interest in a mammalian host, however, remains a major challenge. Here, using phage display technology, we have identified peptides that bind specifically to CD177, a neutrophil-specific surface molecule. We have attached these peptides to fluorescent, lipid-based nanoparticles and confirmed targeting and delivery to cultured cells ectopically presenting either human or mouse CD177. In addition, we have shown peptide-nanoparticle binding specifically to neutrophils in human and mouse blood. We anticipate that these or related tagged nanoparticles may be therapeutically useful for delivery of siRNAs or ASOs to neutrophils for transient knockdown of pro-inflammatory proteins such as the C5a receptor.
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Affiliation(s)
- Heini M. Miettinen
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States of America
- * E-mail:
| | - Jeannie M. Gripentrog
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States of America
| | - Connie I. Lord
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States of America
| | - Jon O. Nagy
- NanoValent Pharmaceuticals, Inc., Bozeman, MT, United States of America
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Abstract
Chronic, persistent itch is a devastating symptom that causes much suffering. In recent years, there has been great progress made in understanding the molecules, cells, and circuits underlying itch sensation. Once thought to be carried by pain-sensing neurons, itch is now believed to be capable of being transmitted by dedicated sensory labeled lines. Members of the Mas-related G protein-coupled receptor (Mrgpr) family demarcate an itch-specific labeled line in the peripheral nervous system. In the spinal cord, the expression of other proteins identifies additional populations of itch-dedicated sensory neurons. However, as evidence for labeled-line coding has mounted, studies promoting alternative itch-coding strategies have emerged, complicating our understanding of the neural basis of itch. In this review, we cover the molecules, cells, and circuits related to understanding the neural basis of itch, with a focus on the role of Mrgprs in mediating itch sensation.
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Affiliation(s)
- James Meixiong
- The Solomon H. Snyder Department of Neuroscience and the Center for Sensory Biology, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205, USA; ,
| | - Xinzhong Dong
- The Solomon H. Snyder Department of Neuroscience and the Center for Sensory Biology, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205, USA; , .,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Alkanfari I, Gupta K, Jahan T, Ali H. Naturally Occurring Missense MRGPRX2 Variants Display Loss of Function Phenotype for Mast Cell Degranulation in Response to Substance P, Hemokinin-1, Human β-Defensin-3, and Icatibant. THE JOURNAL OF IMMUNOLOGY 2018; 201:343-349. [PMID: 29794017 DOI: 10.4049/jimmunol.1701793] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 05/03/2018] [Indexed: 12/19/2022]
Abstract
Human mast cells (MCs) express a novel G protein-coupled receptor (GPCR) known as Mas-related GPCR X2 (MRGPRX2). Activation of this receptor by a diverse group of cationic ligands such as neuropeptides, host defense peptides, and Food and Drug Administration-approved drugs contributes to chronic inflammatory diseases and pseudoallergic drug reactions. For most GPCRs, the extracellular (ECL) domains and their associated transmembrane (TM) domains display the greatest structural diversity and are responsible for binding different ligands. The goal of the current study was to determine if naturally occurring missense variants within MRGPRX2's ECL/TM domains contribute to gain or loss of function phenotype for MC degranulation in response to neuropeptides (substance P and hemokinin-1), a host defense peptide (human β-defensin-3) and a Food and Drug Administration-approved cationic drug (bradykinin B2 receptor antagonist, icatibant). We have identified eight missense variants within MRGPRX2's ECL/TM domains from publicly available exome-sequencing databases. We investigated the ability of MRGPRX2 ligands to induce degranulation in rat basophilic leukemia-2H3 cells individually expressing these naturally occurring MRGPRX2 missense variants. Using stable and transient transfections, we found that all variants express in rat basophilic leukemia cells. However, four natural MRGPRX2 variants, G165E (rs141744602), D184H (rs372988289), W243R (rs150365137), and H259Y (rs140862085) failed to respond to any of the ligands tested. Thus, diverse MRGPRX2 ligands use common sites on the receptor to induce MC degranulation. These findings have important clinical implications for MRGPRX2 and MC-mediated pseudoallergy and chronic inflammatory diseases.
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Affiliation(s)
- Ibrahim Alkanfari
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Kshitij Gupta
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Tahsin Jahan
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Hydar Ali
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104
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35
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Voisin T, Bouvier A, Chiu IM. Neuro-immune interactions in allergic diseases: novel targets for therapeutics. Int Immunol 2018; 29:247-261. [PMID: 28814067 DOI: 10.1093/intimm/dxx040] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 07/05/2017] [Indexed: 12/13/2022] Open
Abstract
Recent studies have highlighted an emerging role for neuro-immune interactions in mediating allergic diseases. Allergies are caused by an overactive immune response to a foreign antigen. The peripheral sensory and autonomic nervous system densely innervates mucosal barrier tissues including the skin, respiratory tract and gastrointestinal (GI) tract that are exposed to allergens. It is increasingly clear that neurons actively communicate with and regulate the function of mast cells, dendritic cells, eosinophils, Th2 cells and type 2 innate lymphoid cells in allergic inflammation. Several mechanisms of cross-talk between the two systems have been uncovered, with potential anatomical specificity. Immune cells release inflammatory mediators including histamine, cytokines or neurotrophins that directly activate sensory neurons to mediate itch in the skin, cough/sneezing and bronchoconstriction in the respiratory tract and motility in the GI tract. Upon activation, these peripheral neurons release neurotransmitters and neuropeptides that directly act on immune cells to modulate their function. Somatosensory and visceral afferent neurons release neuropeptides including calcitonin gene-related peptide, substance P and vasoactive intestinal peptide, which can act on type 2 immune cells to drive allergic inflammation. Autonomic neurons release neurotransmitters including acetylcholine and noradrenaline that signal to both innate and adaptive immune cells. Neuro-immune signaling may play a central role in the physiopathology of allergic diseases including atopic dermatitis, asthma and food allergies. Therefore, getting a better understanding of these cellular and molecular neuro-immune interactions could lead to novel therapeutic approaches to treat allergic diseases.
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Affiliation(s)
- Tiphaine Voisin
- Department of Microbiology and Immunobiology, Division of Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Amélie Bouvier
- Department of Microbiology and Immunobiology, Division of Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Isaac M Chiu
- Department of Microbiology and Immunobiology, Division of Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
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Manorak W, Idahosa C, Gupta K, Roy S, Panettieri R, Ali H. Upregulation of Mas-related G Protein coupled receptor X2 in asthmatic lung mast cells and its activation by the novel neuropeptide hemokinin-1. Respir Res 2018; 19:1. [PMID: 29295703 PMCID: PMC5751818 DOI: 10.1186/s12931-017-0698-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 12/11/2017] [Indexed: 12/21/2022] Open
Abstract
Hemokinin-1 (HK-1) is a novel neuropeptide produced by human bronchial cells and macrophages and causes contraction of human bronchi ex vivo. It is also generated by antigen/IgE-activated murine mast cells (MCs) and contributes to experimental chronic allergic airway inflammation via the activation of the neurokinin receptor-1 (NK-1R) expressed on murine MCs. We found elevated MC numbers in the lungs of individuals who died from asthma (asthma) when compared to lungs of individuals who died from other causes (non-asthma). Mas-related G Protein coupled receptor X2 (MRGPRX2) is a novel G-protein coupled receptor (GPCR) that is expressed predominantly on human MCs. We detected low level of MRGPRX2 in non-asthma lung MCs but its expression was significantly upregulated in asthma lung MCs. HK-1 caused degranulation in a human MC line (LAD2) and RBL-2H3 cells stably expressing MRGPRX2 and this response was resistant to inhibition by an NK-1R antagonist. However, knockdown of MRGPRX2 in LAD2 cells resulted in substantial inhibition of HK-1-induced degranulation. These findings suggest that while HK-1 contributes to the development of experimental asthma in mice via NK-1R on murine MCs the effect of this neuropeptide on human bronchoconstriction likely reflects the activation of MRGPRX2 on lung MCs. Thus, development of selective MRGPRX2 antagonists could serve as novel target for the modulation of asthma.
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Affiliation(s)
- Wichayapha Manorak
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA
| | - Chizobam Idahosa
- Department of Oral Medicine, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Present Address: Departmentof Oral and Maxillofacial Pathology, Medicine and Surgery, Temple University Kornberg School of Dentistry, Philadelphia, PA, USA
| | - Kshitij Gupta
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA
| | - Saptarshi Roy
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA
| | - Reynold Panettieri
- Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, NJ, USA
| | - Hydar Ali
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Philadelphia, PA, 19104-6030, USA.
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37
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Hornum L, Hansen AJ, Tornehave D, Fjording MS, Colmenero P, Wätjen IF, Søe Nielsen NH, Bliddal H, Bartels EM. C5a and C5aR are elevated in joints of rheumatoid and psoriatic arthritis patients, and C5aR blockade attenuates leukocyte migration to synovial fluid. PLoS One 2017; 12:e0189017. [PMID: 29220376 PMCID: PMC5722346 DOI: 10.1371/journal.pone.0189017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 11/18/2017] [Indexed: 11/17/2022] Open
Abstract
Complement activation correlates to rheumatoid arthritis disease activity, and increased amounts of the complement split product C5a is observed in synovial fluids from rheumatoid arthritis patients. Blockade of C5a or its receptor (C5aR) is efficacious in several arthritis models. The aim of this study was to investigate the role of C5a and C5aR in human rheumatoid arthritis and psoriatic arthritis–both with respect to expression and function. Synovial fluid, blood and synovial samples were obtained from rheumatoid arthritis, psoriatic arthritis and osteoarthritis patients as a less inflammatory arthritis type, and blood from healthy subjects. Cells infiltrating synovial tissue were analysed by immunohistochemistry and flow cytometry. SF and blood were analysed for biomarkers by flow cytometry or ELISA. The effect of a blocking anti-human C5aR mAb on leukocyte migration was determined using a Boyden chamber. Appropriate statistical tests were applied for comparisons. C5aR+ cells were detected in most rheumatoid arthritis, in all psoriatic arthritis, but not in non-inflammatory control synovia. C5aR+ cells were primarily neutrophils and macrophages. C5aR+ macrophages were mainly found in lymphoid aggregates in close contact with T cells. C5a levels were increased in both rheumatoid arthritis and psoriatic arthritis synovial fluid compared to osteoarthritis, and in blood from rheumatoid arthritis compared to healthy subjects. Neutrophil and monocyte migration to rheumatoid arthritis synovial fluid was significantly inhibited by anti-C5aR. The data support that the C5a-C5aR axis may be driving the infiltration of inflammatory cells into the synovial fluid and synovium in both rheumatoid and psoriatic arthritis, and suggest that C5a or C5aR may be a promising treatment target in both diseases.
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Affiliation(s)
| | | | | | | | - Paula Colmenero
- Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Inger Falbe Wätjen
- The Parker Institute, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Frederiksberg, Denmark
| | | | - Henning Bliddal
- The Parker Institute, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Frederiksberg, Denmark.,Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Else Marie Bartels
- The Parker Institute, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Frederiksberg, Denmark
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38
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Kwak JW, Laskowski J, Li HY, McSharry MV, Sippel TR, Bullock BL, Johnson AM, Poczobutt JM, Neuwelt AJ, Malkoski SP, Weiser-Evans MC, Lambris JD, Clambey ET, Thurman JM, Nemenoff RA. Complement Activation via a C3a Receptor Pathway Alters CD4 + T Lymphocytes and Mediates Lung Cancer Progression. Cancer Res 2017; 78:143-156. [PMID: 29118090 DOI: 10.1158/0008-5472.can-17-0240] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 06/12/2017] [Accepted: 11/01/2017] [Indexed: 11/16/2022]
Abstract
The complement cascade is a part of the innate immune system that acts primarily to remove pathogens and injured cells. However, complement activation is also peculiarly associated with tumor progression. Here we report mechanistic insights into this association in multiple immunocompetent orthotopic models of lung cancer. After tumor engraftment, we observed systemic activation of the complement cascade as reflected by elevated levels of the key regulator C3a. Notably, growth of primary tumors and metastases was both strongly inhibited in C3-deficient mice (C3-/- mice), with tumors undetectable in many subjects. Growth inhibition was associated with increased numbers of IFNγ+/TNFα+/IL10+ CD4+ and CD8+ T cells. Immunodepletion of CD4+ but not CD8+ T cells in tumor-bearing subjects reversed the inhibitory effects of C3 deletion. Similarly, antagonists of the C3a or C5a receptors inhibited tumor growth. Investigations using multiple tumor cell lines in the orthotopic model suggested the involvement of a C3/C3 receptor autocrine signaling loop in regulating tumor growth. Overall, our findings offer functional evidence that complement activation serves as a critical immunomodulator in lung cancer progression, acting to drive immune escape via a C3/C5-dependent pathway.Significance: This provocative study suggests that inhibiting complement activation may heighten immunotherapeutic responses in lung cancer, offering findings with immediate implications, given the existing clinical availability of complement antagonists. Cancer Res; 78(1); 143-56. ©2017 AACR.
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Affiliation(s)
- Jeff W Kwak
- Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | | | - Howard Y Li
- Department of Medicine, University of Colorado Denver, Aurora, Colorado.,Veterans Affairs Medical Center, Denver, Colorado
| | - Maria V McSharry
- Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Trisha R Sippel
- Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Bonnie L Bullock
- Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Amber M Johnson
- Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | | | | | | | - Mary C Weiser-Evans
- Department of Medicine, University of Colorado Denver, Aurora, Colorado.,Department of Pharmacology, University of Colorado Denver, Aurora, Colorado
| | - John D Lambris
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado
| | - Eric T Clambey
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado
| | - Joshua M Thurman
- Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Raphael A Nemenoff
- Department of Medicine, University of Colorado Denver, Aurora, Colorado. .,Department of Pharmacology, University of Colorado Denver, Aurora, Colorado
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39
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Mast cell degranulation via MRGPRX2 by isolated human albumin fragments. Biochim Biophys Acta Gen Subj 2017; 1861:2530-2534. [DOI: 10.1016/j.bbagen.2017.08.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 08/09/2017] [Accepted: 08/10/2017] [Indexed: 11/20/2022]
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40
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Karhu T, Akiyama K, Vuolteenaho O, Bergmann U, Naito T, Tatemoto K, Herzig KH. Isolation of new ligands for orphan receptor MRGPRX1-hemorphins LVV-H7 and VV-H7. Peptides 2017; 96:61-66. [PMID: 28867075 DOI: 10.1016/j.peptides.2017.08.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 08/15/2017] [Accepted: 08/30/2017] [Indexed: 12/20/2022]
Abstract
The human MAS-related G protein-coupled receptor X1 (MRGPRX1) is a member of the GPCR family. The receptor is primate specific and expressed in the sensory neurons of dorsal root ganglion and trigeminal ganglion, where it is considered to be involved in the pain perception. The MRGPRX1 has unusual binding mechanism, as it is activated by several different ligands as well as several different fragments of precursor proteins. Thus, we hypothesize that it is activated by several unknown compounds as well since the receptor is still classified as orphan. Here, we describe the isolation of two novel endogenous ligands for the MRGPRX1 from human platelet preparation. The isolated ligands are hemoglobin β-chain fragments, known members of the hemorphin family.
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Affiliation(s)
- T Karhu
- Research Unit of Biomedicine, University of Oulu, Oulu, Finland; Biocenter Oulu, University of Oulu, Oulu, Finland.
| | - K Akiyama
- Okinawa Institute of Science and Technology Graduate University, Tancha, Onna-son, Okinawa, Japan
| | - O Vuolteenaho
- Research Unit of Biomedicine, University of Oulu, Oulu, Finland; Nordlab Oulu, Oulu, Finland
| | - U Bergmann
- Biocenter Oulu, University of Oulu, Oulu, Finland; Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - T Naito
- Okinawa Institute of Science and Technology Graduate University, Tancha, Onna-son, Okinawa, Japan; Research Institute of Natural-Drug Leads, Kanagawa University, Hiratsuka, Kanagawa, Japan
| | - K Tatemoto
- Research Unit of Biomedicine, University of Oulu, Oulu, Finland; Biocenter Oulu, University of Oulu, Oulu, Finland
| | - K-H Herzig
- Research Unit of Biomedicine, University of Oulu, Oulu, Finland; Biocenter Oulu, University of Oulu, Oulu, Finland; Department of Gastroenterology and Metabolism, Poznan University of Medical Sciences, Poznan, Poland; Medical Research Center (MRC) and Oulu University Hospital, Oulu, Finland.
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41
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Differential Regulation of Mas-Related G Protein-Coupled Receptor X2-Mediated Mast Cell Degranulation by Antimicrobial Host Defense Peptides and Porphyromonas gingivalis Lipopolysaccharide. Infect Immun 2017; 85:IAI.00246-17. [PMID: 28694291 DOI: 10.1128/iai.00246-17] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Accepted: 07/03/2017] [Indexed: 12/14/2022] Open
Abstract
Porphyromonas gingivalis is a keystone pathogen that contributes to periodontal pathogenesis by disrupting host-microbe homeostasis and promoting dysbiosis. The virulence of P. gingivalis likely reflects an alteration in the lipid A composition of its lipopolysaccharide (LPS) from the penta-acylated (PgLPS1690) to the tetra-acylated (PgLPS1435/1449) form. Mast cells play an important role in periodontitis, but the mechanisms of their activation and regulation remain unknown. The expression of epithelium- and neutrophil-derived host defense peptides (HDPs) (LL-37 and human β-defensin-3), which activate mast cells via Mas-related G protein-coupled receptor X2 (MRGPRX2), is increased in periodontitis. We found that MRGPRX2-expressing mast cells are present in normal gingiva and that their numbers are elevated in patients with chronic periodontitis. Furthermore, HDPs stimulated degranulation in a human mast cell line (LAD2) and in RBL-2H3 cells stably expressing MRGPRX2 (RBL-MRGPRX2). PgLPS1690 caused substantial inhibition of HDP-induced mast cell degranulation, but PgLPS1435/1449 had no effect. A fluorescently labeled HDP (FAM-LL-37) bound to RBL-MRGPRX2 cells, and PgLPS1690 inhibited this binding, but PgLPS1435/1449 had no effect. These findings suggest that low-level inflammation induced by HDP/MRGPRX2-mediated mast cell degranulation contributes to gingival homeostasis but that sustained inflammation due to elevated levels of both HDPs and MRGPRX2-expressing mast cells promotes periodontal disease. Furthermore, differential regulation of HDP-induced mast cell degranulation by PgLPS1690 and PgLPS1435/1449 may contribute to the modulation of disease progression.
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42
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Ali H. Emerging Roles for MAS-Related G Protein-Coupled Receptor-X2 in Host Defense Peptide, Opioid, and Neuropeptide-Mediated Inflammatory Reactions. Adv Immunol 2017; 136:123-162. [PMID: 28950944 DOI: 10.1016/bs.ai.2017.06.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mast cells (MCs) are tissue-resident immune cells that contribute to host defense but are best known for their roles in allergic and inflammatory diseases. In humans, MCs are divided into two subtypes based on the protease content of their secretory granules. Thus, human lung MCs contain only tryptase and are known as MCT, whereas skin MCs contain both tryptase and chymase and are known as MCTC. Patients with severe asthma display elevated MCs in the lung, which undergo phenotypic change from MCT to MCTC. Although the human genome contains four Mas related G protein coupled receptor X (MRGPRX) genes, an important feature of MCTC is that they selectively express MRGPRX2. It is activated by antimicrobial host defense peptides such as human β-defensins and the cathelicidin LL-37 and likely contributes to host defense. MRGPRX2 is also a receptor for the neuropeptide substance P, major basic protein, eosinophil peroxidase, opioids, and many FDA-approved cationic drugs. Increased expression of MRGPRX2 or enhanced downstream signaling likely contributes to chronic inflammatory diseases such as rosacea, atopic dermatitis, chronic urticaria, and severe asthma. In this chapter, I will discuss the expression profile and function of MRGPRX1-4 and review the emerging roles of MRGPRX2 on host defense, chronic inflammatory diseases, and drug-induced pseudoallergic reactions. I will also examine the novel aspects of MRGPRX2 signaling in MCs as it related to degranulation and review the mechanisms of its regulation.
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Affiliation(s)
- Hydar Ali
- University of Pennsylvania School of Dental Medicine, Philadelphia, PA, United States.
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43
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Ali H. Mas-related G protein coupled receptor-X2: A potential new target for modulating mast cell-mediated allergic and inflammatory diseases. JOURNAL OF IMMUNOBIOLOGY 2016; 1:115. [PMID: 28090599 PMCID: PMC5233413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Mast cells (MCs) are tissue resident immune cells that are best known for their roles in allergic and inflammatory diseases. In addition to the high affinity IgE receptor (FcεRI), MCs express numerous G protein coupled receptors (GPCRs), which are the most common targets of drug therapy. Neurokinin 1 receptor (NK-1R) is expressed on MCs and contributes to IgE and non-IgE-mediated responses in mice. Although NK-1R antagonists are highly effective in modulating experimental allergic and inflammatory responses in mice they lack efficacy in humans. This article reviews recent findings that demonstrate that while neuropeptides (NPs) activate murine MCs via NK-1R and Mas related G protein coupled receptor B2 (MrgprB2), they activate human MCs via Mas-related G protein coupled receptor X2 (MRGPRX2). Interestingly, conventional NK-1R antagonists have off-target activity against mouse MrgprB2 but not human MRGPRX2. These findings suggest that the failure to translate studies with NK-1R antagonists from in vivo mouse studies to the clinic likely reflects their lack of effect on human MRGPRX2. A unique feature of MRGPRX2 that distinguishes it from other GPCRs is that it is activated by a diverse group of ligands that include; neuropeptides, cysteine proteases, antimicrobial peptides and cationic proteins released from activated eosinophils. Thus, the development of small molecule MRGPRX2-specific antagonists or neutralizing antibodies may provide new targets for the treatment of MC-mediated allergic and inflammatory diseases.
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Affiliation(s)
- Hydar Ali
- Department of Pathology, University of Pennsylvania School of Dental Medicine, 240 South 40 Street, Philadelphia, PA, 19104-6030
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44
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Gaudenzio N, Sibilano R, Marichal T, Starkl P, Reber LL, Cenac N, McNeil BD, Dong X, Hernandez JD, Sagi-Eisenberg R, Hammel I, Roers A, Valitutti S, Tsai M, Espinosa E, Galli SJ. Different activation signals induce distinct mast cell degranulation strategies. J Clin Invest 2016; 126:3981-3998. [PMID: 27643442 DOI: 10.1172/jci85538] [Citation(s) in RCA: 260] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 08/12/2016] [Indexed: 01/08/2023] Open
Abstract
Mast cells (MCs) influence intercellular communication during inflammation by secreting cytoplasmic granules that contain diverse mediators. Here, we have demonstrated that MCs decode different activation stimuli into spatially and temporally distinct patterns of granule secretion. Certain signals, including substance P, the complement anaphylatoxins C3a and C5a, and endothelin 1, induced human MCs rapidly to secrete small and relatively spherical granule structures, a pattern consistent with the secretion of individual granules. Conversely, activating MCs with anti-IgE increased the time partition between signaling and secretion, which was associated with a period of sustained elevation of intracellular calcium and formation of larger and more heterogeneously shaped granule structures that underwent prolonged exteriorization. Pharmacological inhibition of IKK-β during IgE-dependent stimulation strongly reduced the time partition between signaling and secretion, inhibited SNAP23/STX4 complex formation, and switched the degranulation pattern into one that resembled degranulation induced by substance P. IgE-dependent and substance P-dependent activation in vivo also induced different patterns of mouse MC degranulation that were associated with distinct local and systemic pathophysiological responses. These findings show that cytoplasmic granule secretion from MCs that occurs in response to different activating stimuli can exhibit distinct dynamics and features that are associated with distinct patterns of MC-dependent inflammation.
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45
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Kourtzelis I, Rafail S. The dual role of complement in cancer and its implication in anti-tumor therapy. ANNALS OF TRANSLATIONAL MEDICINE 2016; 4:265. [PMID: 27563652 DOI: 10.21037/atm.2016.06.26] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Chronic inflammation has been linked to the initiation of carcinogenesis, as well as the advancement of established tumors. The polarization of the tumor inflammatory microenvironment can contribute to either the control, or the progression of the disease. The emerging participation of members of the complement cascade in several hallmarks of cancer, renders it a potential target for anti-tumor treatment. Moreover, the presence of complement regulatory proteins (CRPs) in most types of tumor cells is known to impede anti-tumor therapies. This review focuses on our current knowledge of complement's potential involvement in shaping the inflammatory tumor microenvironment and its role on the regulation of angiogenesis and hypoxia. Furthermore, we discuss approaches using complement-based therapies as an adjuvant in tumor immunotherapy.
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Affiliation(s)
- Ioannis Kourtzelis
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, 01307 Dresden, Germany
| | - Stavros Rafail
- Ovarian Cancer Research Center, University of Pennsylvania, Philadelphia, PA 19104-6160, USA
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Subramanian H, Gupta K, Ali H. Roles of Mas-related G protein-coupled receptor X2 on mast cell-mediated host defense, pseudoallergic drug reactions, and chronic inflammatory diseases. J Allergy Clin Immunol 2016; 138:700-710. [PMID: 27448446 DOI: 10.1016/j.jaci.2016.04.051] [Citation(s) in RCA: 279] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 03/21/2016] [Accepted: 04/06/2016] [Indexed: 12/11/2022]
Abstract
Mast cells (MCs), which are granulated tissue-resident cells of hematopoietic lineage, contribute to vascular homeostasis, innate/adaptive immunity, and wound healing. However, MCs are best known for their roles in allergic and inflammatory diseases, such as anaphylaxis, food allergy, rhinitis, itch, urticaria, atopic dermatitis, and asthma. In addition to the high-affinity IgE receptor (FcεRI), MCs express numerous G protein-coupled receptors (GPCRs), which are the largest group of membrane receptor proteins and the most common targets of drug therapy. Antimicrobial host defense peptides, neuropeptides, major basic protein, eosinophil peroxidase, and many US Food and Drug Administration-approved peptidergic drugs activate human MCs through a novel GPCR known as Mas-related G protein-coupled receptor X2 (MRGPRX2; formerly known as MrgX2). Unique features of MRGPRX2 that distinguish it from other GPCRs include their presence both on the plasma membrane and intracellular sites and their selective expression in MCs. In this article we review the possible roles of MRGPRX2 on host defense, drug-induced anaphylactoid reactions, neurogenic inflammation, pain, itch, and chronic inflammatory diseases, such as urticaria and asthma. We propose that host defense peptides that kill microbes directly and activate MCs through MRGPRX2 could serve as novel GPCR targets to modulate host defense against microbial infection. Furthermore, mAbs or small-molecule inhibitors of MRGPRX2 could be developed for the treatment of MC-dependent allergic and inflammatory disorders.
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Affiliation(s)
- Hariharan Subramanian
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pa
| | - Kshitij Gupta
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pa
| | - Hydar Ali
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pa.
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Tiwari V, Tiwari V, He S, Zhang T, Raja SN, Dong X, Guan Y. Mas-Related G Protein-Coupled Receptors Offer Potential New Targets for Pain Therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 904:87-103. [PMID: 26900065 DOI: 10.1007/978-94-017-7537-3_7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The founding member of the Mas-related G-protein-coupled receptor (Mrgpr) family was discovered in 1986. Since then, many more members of this receptor family have been identified in multiple species, and their physiologic functions have been investigated widely. Because they are expressed exclusively in small-diameter primary sensory neurons, the roles of Mrgpr proteins in pain and itch have been best studied. This review will focus specifically on the current knowledge of their roles in pathological pain and the potential development of new pharmacotherapies targeted at some Mrgprs for the treatment of chronic pain. We will also discuss the limitations and future scope of this receptor family in pain treatment.
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Affiliation(s)
- Vineeta Tiwari
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Vinod Tiwari
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Shaoqiu He
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Tong Zhang
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Srinivasa N Raja
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Xinzhong Dong
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Yun Guan
- Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA.
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Gupta K, Subramanian H, Ali H. Modulation of host defense peptide-mediated human mast cell activation by LPS. Innate Immun 2015; 22:21-30. [PMID: 26511058 DOI: 10.1177/1753425915610643] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/15/2015] [Indexed: 01/21/2023] Open
Abstract
Human β-defensin3 (hBD3) and the cathelicidin LL-37 are host defense peptides (HDPs) that directly kill microbes and display immunomodulatory/wound-healing properties via the activation of chemokine, formylpeptide and epidermal growth factor receptors on leukocytes and epithelial cells. A C-terminal 14 amino acid hBD3 peptide with all Cys residues replaced with Ser (CHRG01) and an LL-37 peptide consisting of residues 17-29 (FK-13) display antimicrobial activity but lack immunomodulatory property. Surprisingly, we found that CHRG01 and FK-13 caused Ca(2+) mobilization and degranulation in human mast cells via a novel G protein-coupled receptor known as Mas-related gene-X2 (MrgX2). At local sites of bacterial infection, the negatively charged LPS likely interacts with cationic HDPs to inhibit their activity and thus providing a mechanism for pathogens to escape host defense mechanisms. We found that LPS caused almost complete inhibition of hBD3 and LL-37-induced Ca(2+) mobilization and mast cell degranulation. In contrast, it had no effect on CHRG01 and FK-13-induced mast cell responses. These findings suggest that HDP derivatives that kill microbes, harness mast cell's host defense and wound-healing properties via the activation of MrgX2 but are resistant to inhibition by LPS could be utilized for the treatment of antibiotic-resistant microbial infections.
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Affiliation(s)
- Kshitij Gupta
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, USA
| | - Hariharan Subramanian
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, USA
| | - Hydar Ali
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, USA
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Bader M, Alenina N, Andrade-Navarro MA, Santos RA. MAS and its related G protein-coupled receptors, Mrgprs. Pharmacol Rev 2015; 66:1080-105. [PMID: 25244929 DOI: 10.1124/pr.113.008136] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The Mas-related G protein-coupled receptors (Mrgprs or Mas-related genes) comprise a subfamily of receptors named after the first discovered member, Mas. For most Mrgprs, pruriception seems to be the major function based on the following observations: 1) they are relatively promiscuous in their ligand specificity with best affinities for itch-inducing substances; 2) they are expressed in sensory neurons and mast cells in the skin, the main cellular components of pruriception; and 3) they appear in evolution first in tetrapods, which have arms and legs necessary for scratching to remove parasites or other noxious substances from the skin before they create harm. Because parasites coevolved with hosts, each species faced different parasitic challenges, which may explain another striking observation, the multiple independent duplication and expansion events of Mrgpr genes in different species as a consequence of parallel adaptive evolution. Their predominant expression in dorsal root ganglia anticipates additional functions of Mrgprs in nociception. Some Mrgprs have endogenous ligands, such as β-alanine, alamandine, adenine, RF-amide peptides, or salusin-β. However, because the functions of these agonists are still elusive, the physiologic role of the respective Mrgprs needs to be clarified. The best studied Mrgpr is Mas itself. It was shown to be a receptor for angiotensin-1-7 and to exert mainly protective actions in cardiovascular and metabolic diseases. This review summarizes the current knowledge about Mrgprs, their evolution, their ligands, their possible physiologic functions, and their therapeutic potential.
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Affiliation(s)
- Michael Bader
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany (M.B., N.A., M.A.A.-N.); Charité-University Medicine, Berlin, Germany (M.B.); Institute for Biology, University of Lübeck, Lübeck, Germany (M.B.); and Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil (M.B., N.A., R.A.S.)
| | - Natalia Alenina
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany (M.B., N.A., M.A.A.-N.); Charité-University Medicine, Berlin, Germany (M.B.); Institute for Biology, University of Lübeck, Lübeck, Germany (M.B.); and Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil (M.B., N.A., R.A.S.)
| | - Miguel A Andrade-Navarro
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany (M.B., N.A., M.A.A.-N.); Charité-University Medicine, Berlin, Germany (M.B.); Institute for Biology, University of Lübeck, Lübeck, Germany (M.B.); and Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil (M.B., N.A., R.A.S.)
| | - Robson A Santos
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany (M.B., N.A., M.A.A.-N.); Charité-University Medicine, Berlin, Germany (M.B.); Institute for Biology, University of Lübeck, Lübeck, Germany (M.B.); and Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil (M.B., N.A., R.A.S.)
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Karnik SS, Unal H, Kemp JR, Tirupula KC, Eguchi S, Vanderheyden PML, Thomas WG. International Union of Basic and Clinical Pharmacology. XCIX. Angiotensin Receptors: Interpreters of Pathophysiological Angiotensinergic Stimuli [corrected]. Pharmacol Rev 2015; 67:754-819. [PMID: 26315714 PMCID: PMC4630565 DOI: 10.1124/pr.114.010454] [Citation(s) in RCA: 207] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The renin angiotensin system (RAS) produced hormone peptides regulate many vital body functions. Dysfunctional signaling by receptors for RAS peptides leads to pathologic states. Nearly half of humanity today would likely benefit from modern drugs targeting these receptors. The receptors for RAS peptides consist of three G-protein-coupled receptors—the angiotensin II type 1 receptor (AT1 receptor), the angiotensin II type 2 receptor (AT2 receptor), the MAS receptor—and a type II trans-membrane zinc protein—the candidate angiotensin IV receptor (AngIV binding site). The prorenin receptor is a relatively new contender for consideration, but is not included here because the role of prorenin receptor as an independent endocrine mediator is presently unclear. The full spectrum of biologic characteristics of these receptors is still evolving, but there is evidence establishing unique roles of each receptor in cardiovascular, hemodynamic, neurologic, renal, and endothelial functions, as well as in cell proliferation, survival, matrix-cell interaction, and inflammation. Therapeutic agents targeted to these receptors are either in active use in clinical intervention of major common diseases or under evaluation for repurposing in many other disorders. Broad-spectrum influence these receptors produce in complex pathophysiological context in our body highlights their role as precise interpreters of distinctive angiotensinergic peptide cues. This review article summarizes findings published in the last 15 years on the structure, pharmacology, signaling, physiology, and disease states related to angiotensin receptors. We also discuss the challenges the pharmacologist presently faces in formally accepting newer members as established angiotensin receptors and emphasize necessary future developments.
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Affiliation(s)
- Sadashiva S Karnik
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Hamiyet Unal
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Jacqueline R Kemp
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Kalyan C Tirupula
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Satoru Eguchi
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Patrick M L Vanderheyden
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Walter G Thomas
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
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