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Lee TJ, Nettleford SK, McGlynn A, Carlson BA, Kirimanjeswara GS, Prabhu KS. The role of selenoproteins in neutrophils during inflammation. Arch Biochem Biophys 2022; 732:109452. [PMID: 36336122 PMCID: PMC9712253 DOI: 10.1016/j.abb.2022.109452] [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: 09/29/2022] [Revised: 10/22/2022] [Accepted: 10/29/2022] [Indexed: 11/06/2022]
Abstract
Polymorphonuclear neutrophils (PMNs)-derived ROS are involved in the regulation of multiple functions of PMNs critical in both inflammation and its timely resolution. Selenium is an essential trace element that functions as a gatekeeper of cellular redox homeostasis in the form of selenoproteins. Despite their well-studied involvement in regulating functions of various immune cells, limited studies have focused on the regulation of selenoproteins in PMN and their associated functions. Ex-vivo treatment of murine primary bone marrow derived PMNs with bacterial endotoxin lipopolysaccharide (LPS) indicated temporal regulation of several selenoprotein genes at the mRNA level. However, only glutathione peroxidase 4 (Gpx4) was significantly upregulated, while Selenof, Selenow, and Gpx1 were significantly downregulated in a temporal manner at the protein level. Exposure of PMNs isolated from tRNASec (Trsp)fl/fl S100A8Cre (TrspN) PMN-specific selenoprotein knockout mice, to the Gram-negative bacterium, Citrobacter rodentium, showed decreased bacterial growth, reduced phagocytosis, as well as impaired neutrophil extracellular trap (NET) formation ability, when compared to the wild-type PMNs. Increased extracellular ROS production upon LPS stimulation was also observed in TrspN PMNs that was associated with upregulation of Alox12, Cox2, and iNOS, as well as proinflammatory cytokines such as TNFα and IL-1β. Our data indicate that the inhibition of selenoproteome expression results in alteration of PMN proinflammatory functions, suggesting a potential role of selenoproteins in the continuum of inflammation and resolution.
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Affiliation(s)
- Tai-Jung Lee
- Department of Veterinary & Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Shaneice K Nettleford
- Department of Veterinary & Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Allison McGlynn
- Department of Veterinary & Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Bradley A Carlson
- Office of Research Support, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
| | - Girish S Kirimanjeswara
- Department of Veterinary & Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, PA, 16802, USA
| | - K Sandeep Prabhu
- Department of Veterinary & Biomedical Sciences, Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, PA, 16802, USA.
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2
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Sener S, Ipek V. Investigation of brain mast cells in ovine encephalitic listeriosis. Biotech Histochem 2021; 97:247-253. [PMID: 34157924 DOI: 10.1080/10520295.2021.1941256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Mast cells in the brain are associated with increased inflammation during the acute period following exposure to infection; these cells are important for destroying the infectious agents. We investigated the relation between histopathological lesions and mast cells in sheep brains infected with Listeria. Pons and medulla regions from 17 infected and eight normal sheep brains were examined. Microabscesses and perivascular infiltration were assessed for histopathology. Mast cells were identified using toluidine blue and Listeria monocytogenes were investigated immunohistochemically. We found a significant increase in mast cells in infected sheep brains that was related directly to the extent of brain lesions. A strong correlation was found between mast cells and microabscess formation. A correlation between bacteria level and brain lesions also was observed, but not between bacteria level and mast cells. Our findings indicate that mast cells are increased following Listeria infection in sheep in proportion to the severity of brain lesions; the increase may contribute to acute inflammatory reactions and also may destroy bacteria directly.
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Affiliation(s)
- Suleyman Sener
- Department of Pathology, Faculty of Veterinary Medicine, Burdur Mehmet Akif Ersoy University, Burdur, Turkey
| | - Volkan Ipek
- Department of Pathology, Faculty of Veterinary Medicine, Burdur Mehmet Akif Ersoy University, Burdur, Turkey
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3
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Jiménez M, Cervantes-García D, Córdova-Dávalos LE, Pérez-Rodríguez MJ, Gonzalez-Espinosa C, Salinas E. Responses of Mast Cells to Pathogens: Beneficial and Detrimental Roles. Front Immunol 2021; 12:685865. [PMID: 34211473 PMCID: PMC8240065 DOI: 10.3389/fimmu.2021.685865] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 05/28/2021] [Indexed: 12/19/2022] Open
Abstract
Mast cells (MCs) are strategically located in tissues close to the external environment, being one of the first immune cells to interact with invading pathogens. They are long living effector cells equipped with different receptors that allow microbial recognition. Once activated, MCs release numerous biologically active mediators in the site of pathogen contact, which induce vascular endothelium modification, inflammation development and extracellular matrix remodeling. Efficient and direct antimicrobial mechanisms of MCs involve phagocytosis with oxidative and non-oxidative microbial destruction, extracellular trap formation, and the release of antimicrobial substances. MCs also contribute to host defense through the attraction and activation of phagocytic and inflammatory cells, shaping the innate and adaptive immune responses. However, as part of their response to pathogens and under an impaired, sustained, or systemic activation, MCs may contribute to tissue damage. This review will focus on the current knowledge about direct and indirect contribution of MCs to pathogen clearance. Antimicrobial mechanisms of MCs are addressed with special attention to signaling pathways involved and molecular weapons implicated. The role of MCs in a dysregulated host response that can increase morbidity and mortality is also reviewed and discussed, highlighting the complexity of MCs biology in the context of host-pathogen interactions.
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Affiliation(s)
- Mariela Jiménez
- Laboratory of Immunology, Department of Microbiology, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
| | - Daniel Cervantes-García
- Laboratory of Immunology, Department of Microbiology, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico.,Cátedras CONACYT, National Council of Science and Technology, Mexico City, Mexico
| | - Laura E Córdova-Dávalos
- Laboratory of Immunology, Department of Microbiology, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
| | - Marian Jesabel Pérez-Rodríguez
- Department of Pharmacobiology, Centro de Investigación y de Estudios Avanzados (Cinvestav), Unidad Sede Sur, Mexico City, Mexico
| | - Claudia Gonzalez-Espinosa
- Department of Pharmacobiology, Centro de Investigación y de Estudios Avanzados (Cinvestav), Unidad Sede Sur, Mexico City, Mexico
| | - Eva Salinas
- Laboratory of Immunology, Department of Microbiology, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
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4
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Voss M, Kotrba J, Gaffal E, Katsoulis-Dimitriou K, Dudeck A. Mast Cells in the Skin: Defenders of Integrity or Offenders in Inflammation? Int J Mol Sci 2021; 22:ijms22094589. [PMID: 33925601 PMCID: PMC8123885 DOI: 10.3390/ijms22094589] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/23/2021] [Accepted: 04/25/2021] [Indexed: 12/13/2022] Open
Abstract
Mast cells (MCs) are best-known as key effector cells of immediate-type allergic reactions that may even culminate in life-threatening anaphylactic shock syndromes. However, strategically positioned at the host–environment interfaces and equipped with a plethora of receptors, MCs also play an important role in the first-line defense against pathogens. Their main characteristic, the huge amount of preformed proinflammatory mediators embedded in secretory granules, allows for a rapid response and initiation of further immune effector cell recruitment. The same mechanism, however, may account for detrimental overshooting responses. MCs are not only detrimental in MC-driven diseases but also responsible for disease exacerbation in other inflammatory disorders. Focusing on the skin as the largest immune organ, we herein review both beneficial and detrimental functions of skin MCs, from skin barrier integrity via host defense mechanisms to MC-driven inflammatory skin disorders. Moreover, we emphasize the importance of IgE-independent pathways of MC activation and their role in sustained chronic skin inflammation and disease exacerbation.
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Affiliation(s)
- Martin Voss
- Medical Faculty, Institute for Molecular and Clinical Immunology, Otto-Von-Guericke-University Magdeburg, 39120 Magdeburg, Germany; (M.V.); (J.K.); (K.K.-D.)
| | - Johanna Kotrba
- Medical Faculty, Institute for Molecular and Clinical Immunology, Otto-Von-Guericke-University Magdeburg, 39120 Magdeburg, Germany; (M.V.); (J.K.); (K.K.-D.)
| | - Evelyn Gaffal
- Laboratory for Experimental Dermatology, Department of Dermatology, University Hospital Magdeburg, 39120 Magdeburg, Germany;
| | - Konstantinos Katsoulis-Dimitriou
- Medical Faculty, Institute for Molecular and Clinical Immunology, Otto-Von-Guericke-University Magdeburg, 39120 Magdeburg, Germany; (M.V.); (J.K.); (K.K.-D.)
| | - Anne Dudeck
- Medical Faculty, Institute for Molecular and Clinical Immunology, Otto-Von-Guericke-University Magdeburg, 39120 Magdeburg, Germany; (M.V.); (J.K.); (K.K.-D.)
- Health Campus Immunology, Infectiology and Inflammation, Otto-Von-Guericke-University Magdeburg, 39120 Magdeburg, Germany
- Correspondence:
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5
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Early immune innate hallmarks and microbiome changes across the gut during Escherichia coli O157: H7 infection in cattle. Sci Rep 2020; 10:21535. [PMID: 33299023 PMCID: PMC7726576 DOI: 10.1038/s41598-020-78752-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 11/27/2020] [Indexed: 12/24/2022] Open
Abstract
The zoonotic enterohemorrhagic Escherichia coli (EHEC) O157: H7 bacterium causes diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS) in humans. Cattle are primary reservoirs and EHEC O157: H7; the bacteria predominately inhabit the colon and recto-anal junctions (RAJ). The early innate immune reactions in the infected gut are critical in the pathogenesis of EHEC O157: H7. In this study, calves orally inoculated with EHEC O157: H7 showed infiltration of neutrophils in the lamina propria of ileum and RAJ at 7 and 14 days post-infection. Infected calves had altered mucin layer and mast cell populations across small and large intestines. There were differential transcription expressions of key bovine β defensins, tracheal antimicrobial peptide (TAP) in the ileum, and lingual antimicrobial peptide (LAP) in RAJ. The main Gram-negative bacterial/LPS signaling Toll-Like receptor 4 (TLR4) was downregulated in RAJ. Intestinal infection with EHEC O157: H7 impacted the gut bacterial communities and influenced the relative abundance of Negativibacillus and Erysipelotrichaceae in mucosa-associated bacteria in the rectum. Thus, innate immunity in the gut of calves showed unique characteristics during infection with EHEC O157: H7, which occurred in the absence of major clinical manifestations but denoted an active immunological niche.
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6
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Fritscher J, Amberger D, Dyckhoff S, Bewersdorf JP, Masouris I, Voelk S, Hammerschmidt S, Schmetzer HM, Klein M, Pfister HW, Koedel U. Mast Cells Are Activated by Streptococcus pneumoniae In Vitro but Dispensable for the Host Defense Against Pneumococcal Central Nervous System Infection In Vivo. Front Immunol 2018; 9:550. [PMID: 29616039 PMCID: PMC5867309 DOI: 10.3389/fimmu.2018.00550] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 03/05/2018] [Indexed: 01/01/2023] Open
Abstract
Mast cells reside on and near the cerebral vasculature, the predominant site of pneumococcal entry into the central nervous system (CNS). Although mast cells have been reported to be crucial in protecting from systemic bacterial infections, their role in bacterial infections of the CNS remained elusive. Here, we assessed the role of mast cells in pneumococcal infection in vitro and in vivo. In introductory experiments using mouse bone marrow-derived mast cells (BMMC), we found that (i) BMMC degranulate and release selected cytokines upon exposure to Streptococcus pneumoniae, (ii) the response of BMMC varies between different pneumococcal serotypes and (iii) is dependent on pneumolysin. Intriguingly though, apart from a slight enhancement of cerebrospinal fluid (CSF) pleocytosis, neither two different mast cell-deficient Kit mutant mouse strains (WBB6F1-KitW/Wv and C57BL/6 KitW-sh/W-sh mice) nor pharmacologic mast cell stabilization with cromoglycate had any significant impact on the disease phenotype of experimental pneumococcal meningitis. The incomplete reversal of the enhanced CSF pleocytosis by local mast cell engraftment suggests that this phenomenon is caused by other c-Kit mutation-related mechanisms than mast cell deficiency. In conclusion, our study suggests that mast cells can be activated by S. pneumoniae in vitro. However, mast cells do not play a significant role as sentinels of pneumococcal CSF invasion and initiators of innate immunity in vivo.
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Affiliation(s)
- Johanna Fritscher
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Daniel Amberger
- Department of Internal Medicine III (Oncology), University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Susanne Dyckhoff
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Jan Philipp Bewersdorf
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Ilias Masouris
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Stefanie Voelk
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, Ernst Moritz Arndt University Greifswald, Greifswald, Germany
| | - Helga Maria Schmetzer
- Department of Internal Medicine III (Oncology), University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Matthias Klein
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Hans-Walter Pfister
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Uwe Koedel
- Department of Neurology, University Hospital, Ludwig-Maximilians-University, Munich, Germany
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7
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Abstract
Mast cells are hematopoietic progenitor-derived, granule-containing immune cells that are widely distributed in tissues that interact with the external environment, such as the skin and mucosal tissues. It is well-known that mast cells are significantly involved in IgE-mediated allergic reactions, but because of their location, it has also been long hypothesized that mast cells can act as sentinel cells that sense pathogens and initiate protective immune responses. Using mast cell or mast cell protease-deficient murine models, recent studies by our groups and others indicate that mast cells have pleiotropic regulatory roles in immunological responses against pathogens. In this review, we discuss studies that demonstrate that mast cells can either promote host resistance to infections caused by bacteria and fungi or contribute to dysregulated immune responses that can increase host morbidity and mortality. Overall, these studies indicate that mast cells can influence innate immune responses against bacterial and fungal infections via multiple mechanisms. Importantly, the contribution of mast cells to infection outcomes depends in part on the infection model, including the genetic approach used to assess the influence of mast cells on host immunity, hence highlighting the complexity of mast cell biology in the context of innate immune responses.
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Affiliation(s)
- Adrian M Piliponsky
- Departments of Pediatrics and Pathology, University of Washington, Seattle, WA, USA
- Seattle Children's Research Institute, Seattle, WA, USA
| | - Luigina Romani
- Pathology Section, Department of Experimental Medicine, University of Perugia, Perugia, Italy
- Center of functional genomics (C.U.R.Ge.F.), Department of Experimental Medicine, University of Perugia, Perugia, Italy
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8
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Epithelial Histone Deacetylase 3 Instructs Intestinal Immunity by Coordinating Local Lymphocyte Activation. Cell Rep 2018; 19:1165-1175. [PMID: 28494866 DOI: 10.1016/j.celrep.2017.04.046] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 03/17/2017] [Accepted: 04/14/2017] [Indexed: 12/20/2022] Open
Abstract
Mucosal tissues are constantly in direct contact with diverse beneficial and pathogenic microbes, highlighting the need for orchestrating complex microbial signals to sustain effective host defense. Here, we show an essential role for intestinal epithelial cell expression of histone deacetylase 3 (HDAC3) in responding to pathogenic microbes and activating protective innate immunity. Mice lacking HDAC3 in intestinal epithelial cells were more susceptible to Citrobacter rodentium when under tonic stimulation by the commensal microbiota. This impaired host defense reflected significantly decreased IFNγ production by intraepithelial CD8+ T cells early during infection. Further, HDAC3 was necessary for infection-induced epithelial expression of the IFNγ-inducing factor IL-18, and administration of IL-18 restored IFNγ activity to resident CD8+ T cells and reduced infection. Thus, HDAC3 mediates communication between intestinal epithelial cells and resident lymphocytes, revealing that epithelial priming by an epigenetic modifier may direct mucosal regulation of host defense against pathogenic microbes.
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9
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Kittana H, Quintero-Villegas MI, Bindels LB, Gomes-Neto JC, Schmaltz RJ, Segura Munoz RR, Cody LA, Moxley RA, Hostetter J, Hutkins RW, Ramer-Tait AE. Galactooligosaccharide supplementation provides protection against Citrobacter rodentium-induced colitis without limiting pathogen burden. MICROBIOLOGY-SGM 2017; 164:154-162. [PMID: 29256851 DOI: 10.1099/mic.0.000593] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Many enteric pathogens, including Salmonella and enteropathogenic and enterohemorrhagic Escherichia coli, express adhesins that recognize and bind to carbohydrate moieties expressed on epithelial cells. An attractive strategy for inhibiting bacterial adherence employs molecules that mimic these epithelial binding sites. Prebiotic oligosaccharides are non-digestible, fermentable fibres capable of modulating the gut microbiota. Moreover, they may act as molecular decoys that competitively inhibit adherence of pathogens to host cells. In particular, galactooligosaccharides (GOS) and other prebiotic fibres have been shown to inhibit pathogen adherence to epithelial cells in vitro. In the present study, we determined the ability of prophylactic GOS administration to reduce enteric pathogen adherence both in vitro and in vivo as well as protect against intestinal inflammation. GOS supplementation significantly reduced the adherence of the epithelial-adherent murine bacterial pathogen Citrobacter rodentium in a dose-dependent manner to the surface of epithelial cells in vitro. A 1- to 2-log reduction in bacterial adherence was observed at the lowest and highest doses tested, respectively. However, mouse studies revealed that treatment with GOS neither reduced the adherence of C. rodentium to the distal colon nor decreased its dissemination to systemic organs. Despite the absence of adherence inhibition, colonic disease scores for GOS-treated, C. rodentium-infected mice were significantly lower than those of untreated C. rodentium-infected animals (P=0.028). Together, these data suggest that GOS has a direct protective effect in ameliorating disease severity following C. rodentium infection through an anti-adherence-independent mechanism.
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Affiliation(s)
- Hatem Kittana
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | | | - Laure B Bindels
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - João Carlos Gomes-Neto
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Robert J Schmaltz
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Rafael R Segura Munoz
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Liz A Cody
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Rodney A Moxley
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Jesse Hostetter
- Department of Veterinary Pathology, Iowa State University, Ames, Iowa, USA
| | - Robert W Hutkins
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Amanda E Ramer-Tait
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, USA
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10
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Garcia-Rodriguez KM, Goenka A, Alonso-Rasgado MT, Hernández-Pando R, Bulfone-Paus S. The Role of Mast Cells in Tuberculosis: Orchestrating Innate Immune Crosstalk? Front Immunol 2017; 8:1290. [PMID: 29089945 PMCID: PMC5650967 DOI: 10.3389/fimmu.2017.01290] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 09/26/2017] [Indexed: 12/30/2022] Open
Abstract
Tuberculosis causes more annual deaths globally than any other infectious disease. However, progress in developing novel vaccines, diagnostics, and therapies has been hampered by an incomplete understanding of the immune response to Mycobacterium tuberculosis (Mtb). While the role of many immune cells has been extensively explored, mast cells (MCs) have been relatively ignored. MCs are tissue resident cells involved in defense against bacterial infections playing an important role mediating immune cell crosstalk. This review discusses specific interactions between MCs and Mtb, their contribution to both immunity and disease pathogenesis, and explores their role in orchestrating other immune cells against infections.
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Affiliation(s)
- Karen M. Garcia-Rodriguez
- Manchester Collaborative Centre for Inflammation Research, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
- Faculty of Science and Engineering, School of Materials, University of Manchester, Manchester, United Kingdom
| | - Anu Goenka
- Manchester Collaborative Centre for Inflammation Research, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
| | - Maria T. Alonso-Rasgado
- Faculty of Science and Engineering, School of Materials, University of Manchester, Manchester, United Kingdom
| | - Rogelio Hernández-Pando
- Departamento de Patología Experimental, Instituto Nacional de Ciencias Médicas y Nutrición “Salvador Zubiran”, Mexico City, Mexico
| | - Silvia Bulfone-Paus
- Manchester Collaborative Centre for Inflammation Research, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
- Division of Musculoskeletal and Dermatological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
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11
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Chen W, Lu X, Chen Y, Li M, Mo P, Tong Z, Wang W, Wan W, Su G, Xu J, Yu C. Steroid Receptor Coactivator 3 Contributes to Host Defense against Enteric Bacteria by Recruiting Neutrophils via Upregulation of CXCL2 Expression. THE JOURNAL OF IMMUNOLOGY 2017; 198:1606-1615. [PMID: 28053238 DOI: 10.4049/jimmunol.1600300] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 11/30/2016] [Indexed: 01/11/2023]
Abstract
Steroid receptor coactivator 3 (SRC-3) is a transcriptional coactivator that interacts with nuclear receptors and some other transcription factors to enhance their effects on target gene transcription. We reported previously that SRC-3-deficient (SRC-3-/-) mice are extremely susceptible to Escherichia coli-induced septic peritonitis as a result of uncontrolled inflammation and a defect in bacterial clearance. In this study, we observed significant upregulation of SRC-3 in colonic epithelial cells in response to Citrobacter rodentium infection. Based on these findings, we hypothesized that SRC-3 is involved in host defense against attaching and effacing bacterial infection. We compared the responses of SRC-3-/- and wild-type mice to intestinal C. rodentium infection. We found that SRC-3-/- mice exhibited delayed clearance of C. rodentium and more severe tissue pathology after oral infection with C. rodentium compared with wild-type mice. SRC-3-/- mice expressed normal antimicrobial peptides in the colons but exhibited delayed recruitment of neutrophils into the colonic mucosa. Accordingly, SRC-3-/- mice showed a delayed induction of CXCL2 and CXCL5 in colonic epithelial cells, which are responsible for neutrophil recruitment. At the molecular level, we found that SRC-3 can activate the NF-κB signaling pathway to promote CXCL2 expression at the transcriptional level. Collectively, we show that SRC-3 contributes to host defense against enteric bacteria, at least in part via upregulating CXCL2 expression to recruit neutrophils.
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Affiliation(s)
- Wenbo Chen
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China.,The First Affiliated Hospital of Xiamen University, Xiamen 361001, China; and
| | - Xuqiang Lu
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Yuan Chen
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Ming Li
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Pingli Mo
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Zhangwei Tong
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Wei Wang
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Wei Wan
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Guoqiang Su
- The First Affiliated Hospital of Xiamen University, Xiamen 361001, China; and
| | - Jianming Xu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030
| | - Chundong Yu
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China;
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12
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Campillo-Navarro M, Leyva-Paredes K, Donis-Maturano L, González-Jiménez M, Paredes-Vivas Y, Cerbulo-Vázquez A, Serafín-López J, García-Pérez B, Ullrich SE, Flores-Romo L, Pérez-Tapia SM, Estrada-Parra S, Estrada-García I, Chacón-Salinas R. Listeria monocytogenes induces mast cell extracellular traps. Immunobiology 2016; 222:432-439. [PMID: 27520114 DOI: 10.1016/j.imbio.2016.08.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 07/04/2016] [Accepted: 08/05/2016] [Indexed: 12/14/2022]
Abstract
Mast cells play an essential role in different immunological phenomena including allergy and infectious diseases. Several bacteria induce mast cell activation leading to degranulation and the production of several cytokines and chemokines. However, mast cells also have different microbicidal activities such as phagocytosis and the release of DNA with embedded granular proteins known as Mast Cell Extracellular Traps (MCETs). Although previous reports indicate that extracellular bacteria are able to induce MCETs little is known if intracellular bacteria can induce these structures. In this work, we evaluated MCETs induction by the intracellular bacteria Listeria monocytogenes. We found that mast cells released DNA after stimulation with L. monocytogenes, and this DNA was complexed to histone and tryptase. Before extracellular DNA release, L. monocytogenes induced modifications to the mast cell nuclear envelope and DNA was detected outside the nucleus. L. monocytogenes stimulated mast cells to produce significant amounts of reactive oxygen species (ROS) and blocking NADPH oxidase diminished DNA release by mast cells. Finally, MCETs showed antimicrobial activity against L. monocytogenes that was partially blocked when β-hexosaminidase activity was inhibited. These results show that L. monocytogenes induces mast cells to produce microbicidal MCETs, suggesting a role for mast cells in containing infection beyond the induction of inflammation.
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Affiliation(s)
- Marcia Campillo-Navarro
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico
| | - Kahiry Leyva-Paredes
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico
| | - Luis Donis-Maturano
- Department of Cell Biology, Cinvestav, Instituto Politécnico Nacional, Mexico
| | | | | | | | - Jeanet Serafín-López
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico
| | - Blanca García-Pérez
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico
| | - Stephen E Ullrich
- Department of Immunology and The Center for Cancer Immunology Research, The University of Texas, MD Anderson Cancer Center, USA; The University of Texas Graduate School of Biological Sciences at Houston, TX, USA
| | | | - Sonia M Pérez-Tapia
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico; Unidad de Desarrollo e Investigación en Bioprocesos (UDIBI), Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico
| | - Sergio Estrada-Parra
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico
| | - Iris Estrada-García
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico
| | - Rommel Chacón-Salinas
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico; Unidad de Desarrollo e Investigación en Bioprocesos (UDIBI), Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, ENCB-IPN, Mexico.
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13
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Möllerherm H, von Köckritz-Blickwede M, Branitzki-Heinemann K. Antimicrobial Activity of Mast Cells: Role and Relevance of Extracellular DNA Traps. Front Immunol 2016; 7:265. [PMID: 27486458 PMCID: PMC4947581 DOI: 10.3389/fimmu.2016.00265] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 06/22/2016] [Indexed: 01/08/2023] Open
Abstract
Mast cells (MCs) have been shown to release their nuclear DNA and subsequently form mast cell extracellular traps (MCETs) comparable to neutrophil extracellular traps, which are able to entrap and kill various microbes. The formation of extracellular traps is associated with the disruption of the nuclear membrane, which leads to mixing of nuclear compounds with granule components and causes the death of the cell, a process called ETosis. The question arises why do MCs release MCETs although they are very well known as multifunctional long-living sentinel cells? MCs are known to play a role during allergic reactions and certain parasitic infections. Nonetheless, they are also critical components of the early host innate immune response to bacterial and fungal pathogens: MCs contribute to the initiation of the early immune response by recruiting effector cells including neutrophils and macrophages by locally releasing inflammatory mediators, such as TNF-α. Moreover, various studies demonstrate that MCs are able to eliminate microbes through intracellular as well as extracellular antimicrobial mechanisms, including MCET formation similar to that of professional phagocytes. Recent literature leads to the suggestion that MCET formation is not the result of a passive release of DNA and granule proteins during cellular disintegration, but rather an active and controlled process in response to specific stimulation, which contributes to the innate host defense. This review will discuss the different known aspects of the antimicrobial activities of MCs with a special focus on MCETs, and their role and relevance during infection and inflammation.
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Affiliation(s)
- Helene Möllerherm
- Department of Physiological Chemistry, University for Veterinary Medicine Hannover , Hanover , Germany
| | - Maren von Köckritz-Blickwede
- Department of Physiological Chemistry, University for Veterinary Medicine Hannover, Hanover, Germany; Research Center for Emerging Infections and Zoonoses (RIZ), University for Veterinary Medicine Hannover, Hanover, Germany
| | - Katja Branitzki-Heinemann
- Department of Physiological Chemistry, University for Veterinary Medicine Hannover , Hanover , Germany
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NOD1 and NOD2 Interact with the Phagosome Cargo in Mast Cells: A Detailed Morphological Evidence. Inflammation 2016; 38:1113-25. [PMID: 25502289 DOI: 10.1007/s10753-014-0077-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mast cells (MC) play a key role in triggering the inflammatory process and share some functions with professional phagocytes. It is not clear whether or not the phagocytic process in MC follows the same route and has the same meaning of that of professional phagocytes. Herein we analyze in detail the structure of the phagosome in rat peritoneal mast cells (RPMC). The ultrastructural analysis of the phagosome, containing either model particles or bacteria, reveals that these vacuoles are very tight, and in several areas, their membrane seems to have dissolved. RPMC express NOD1 and NOD2 proteins whose role is to recognize intracellular foreign components and induce the production of pro-inflammatory mediators. Following Escherichia coli ingestion, both these molecules are found on the phagosome membrane and on ingested pathogens, together with phagosome maturation markers. These findings suggest that in RPMC the ingested cargo can, through interruptions of the phagosome membrane, interact directly with NODs, which act as switches in the process of cytokine production.
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15
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Johnzon CF, Rönnberg E, Pejler G. The Role of Mast Cells in Bacterial Infection. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:4-14. [DOI: 10.1016/j.ajpath.2015.06.024] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 06/17/2015] [Accepted: 06/24/2015] [Indexed: 01/21/2023]
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16
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CD40 Ligand Deficient C57BL/6 Mouse Is a Potential Surrogate Model of Human X-Linked Hyper IgM (X-HIGM) Syndrome for Characterizing Immune Responses against Pathogens. BIOMED RESEARCH INTERNATIONAL 2015; 2015:679850. [PMID: 26064940 PMCID: PMC4433659 DOI: 10.1155/2015/679850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 12/10/2014] [Indexed: 01/12/2023]
Abstract
Individuals with X-HIGM syndrome fail to express functional CD40 ligand; consequently they cannot mount effective protective antibody responses against pathogenic bacteria. We evaluated, compared, and characterized the humoral immune response of wild type (WT) and C57-CD40L deficient (C57-CD40L−/−) mice infected with Citrobacter rodentium. Basal serum isotype levels were similar for IgM and IgG3 among mice, while total IgG and IgG2b concentrations were significantly lower in C57-CD40L−/− mice compared with WT. Essentially IgG1 and IgG2c levels were detectable only in WT mice. C57-CD40L−/− animals, orally inoculated with 2 × 109 CFU, presented several clinical manifestations since the second week of infection and eventually died. In contrast at this time point no clinical manifestations were observed among C57-CD40L−/− mice infected with 1 × 107 CFU. Infection was subclinical in WT mice inoculated with either bacterial dose. The serum samples from infected mice (1 × 107 CFU), collected at day 14 after infection, had similar C. rodentium-specific IgM titres. Although C57-CD40L−/− animals had lower IgG and IgG2b titres than WT mice, C57-CD40L−/− mice sera displayed complement-mediated bactericidal activity against C. rodentium. C. rodentium-infected C57-CD40L−/− mice are capable of producing antibodies that are protective. C57-CD40L−/− mouse is a useful surrogate model of X-HIGM syndrome for studying immune responses elicited against pathogens.
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Koroleva EP, Halperin S, Gubernatorova EO, Macho-Fernandez E, Spencer CM, Tumanov AV. Citrobacter rodentium-induced colitis: A robust model to study mucosal immune responses in the gut. J Immunol Methods 2015; 421:61-72. [PMID: 25702536 DOI: 10.1016/j.jim.2015.02.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 02/11/2015] [Accepted: 02/11/2015] [Indexed: 12/14/2022]
Abstract
Citrobacter rodentium is a natural mouse pathogen which reproducibly infects mice and causes intestinal disease. The C. rodentium model of infection is very useful for investigating host-pathogen immune interactions in the gut, and can also be used to understand the pathogenesis of several important human intestinal disorders, including Crohn's disease, ulcerative colitis, dysbiosis and colon tumorigenesis. Both innate and adaptive immune responses play a critical role in protection against C. rodentium. Here, we summarize the role of immune components in protection against C. rodentium and describe techniques for the analysis of innate and adaptive mucosal immune responses, including setting up the infection, analysis of colonic hyperplasia and bacterial dissemination, evaluation of antibody responses, and purification and analysis of intestinal epithelial and lymphoid cells.
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Affiliation(s)
| | | | | | | | | | - Alexei V Tumanov
- Trudeau Institute, Saranac Lake, NY 12983, USA; Engelhardt Institute of Molecular Biology, Moscow, Russia.
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18
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Rönnberg E, Johnzon CF, Calounova G, Garcia Faroldi G, Grujic M, Hartmann K, Roers A, Guss B, Lundequist A, Pejler G. Mast cells are activated by Staphylococcus aureus in vitro but do not influence the outcome of intraperitoneal S. aureus infection in vivo. Immunology 2014; 143:155-63. [PMID: 24689370 DOI: 10.1111/imm.12297] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 03/24/2014] [Accepted: 03/27/2014] [Indexed: 12/17/2022] Open
Abstract
Staphylococcus aureus is a major pathogen that can cause a broad spectrum of serious infections including skin infections, pneumonia and sepsis. Peritoneal mast cells have been implicated in the host response towards various bacterial insults and to provide mechanistic insight into the role of mast cells in intraperitoneal bacterial infection we here studied the global effects of S. aureus on mast cell gene expression. After co-culture of peritoneal mast cells with live S. aureus we found by gene array analysis that they up-regulate a number of genes. Many of these corresponded to pro-inflammatory cytokines, including interleukin-3, interleukin-13 and tumour necrosis factor-α. The cytokine induction in response to S. aureus was confirmed by ELISA. To study the role of peritoneal mast cells during in vivo infection with S. aureus we used newly developed Mcpt5-Cre(+) × R-DTA mice in which mast cell deficiency is independent of c-Kit. This is in contrast to previous studies in which an impact of mast cells on bacterial infection has been proposed based on the use of mice whose mast cell deficiency is a consequence of defective c-Kit signalling. Staphylococcus aureus was injected intraperitoneally into mast-cell-deficient Mcpt5-Cre(+) × R-DTA mice using littermate mast-cell-sufficient mice as controls. We did not observe any difference between mast-cell-deficient and control mice with regard to weight loss, bacterial clearance, inflammation or cytokine production. We conclude that, despite peritoneal mast cells being activated by S. aureus in vitro, they do not influence the in vivo manifestations of intraperitoneal S. aureus infection.
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Affiliation(s)
- Elin Rönnberg
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden
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19
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da Silva EZM, Jamur MC, Oliver C. Mast cell function: a new vision of an old cell. J Histochem Cytochem 2014; 62:698-738. [PMID: 25062998 PMCID: PMC4230976 DOI: 10.1369/0022155414545334] [Citation(s) in RCA: 389] [Impact Index Per Article: 38.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 07/07/2014] [Indexed: 02/06/2023] Open
Abstract
Since first described by Paul Ehrlich in 1878, mast cells have been mostly viewed as effectors of allergy. It has been only in the past two decades that mast cells have gained recognition for their involvement in other physiological and pathological processes. Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment. Mast cell maturation, phenotype and function are a direct consequence of the local microenvironment and have a marked influence on their ability to specifically recognize and respond to various stimuli through the release of an array of biologically active mediators. These features enable mast cells to act as both first responders in harmful situations as well as to respond to changes in their environment by communicating with a variety of other cells implicated in physiological and immunological responses. Therefore, the critical role of mast cells in both innate and adaptive immunity, including immune tolerance, has gained increased prominence. Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases. This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role.
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Affiliation(s)
- Elaine Zayas Marcelino da Silva
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil (EZMDS, MCJ, CO)
| | - Maria Célia Jamur
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil (EZMDS, MCJ, CO)
| | - Constance Oliver
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil (EZMDS, MCJ, CO)
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Abstract
ABSTRACT
The inflammatory response is an integral part of host defense against enterohemorrhagic
Escherichia coli
(EHEC) infection and also contributes to disease pathology. In this article we explore the factors leading to inflammation during EHEC infection and the mechanisms EHEC and other attaching and effacing (A/E) pathogens have evolved to suppress inflammatory signaling. EHEC stimulates an inflammatory response in the intestine through host recognition of bacterial components such as flagellin and lipopolysaccharide. In addition, the activity of Shiga toxin and some type III secretion system effectors leads to increased tissue inflammation. Various infection models of EHEC and other A/E pathogens have revealed many of the immune factors that mediate this response. In particular, the outcome of infection is greatly influenced by the ability of an infected epithelial cell to mount an effective host inflammatory response. The inflammatory response of infected enterocytes is counterbalanced by the activity of type III secretion system effectors such as NleE and NleC that modify and inhibit components of the signaling pathways that lead to proinflammatory cytokine production. Overall, A/E pathogens have taught us that innate mucosal immune responses in the gastrointestinal tract during infection with A/E pathogens are highly complex and ultimate clearance of the pathogen depends on multiple factors, including inflammatory mediators, bacterial burden, and the function and integrity of resident intestinal epithelial cells.
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21
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Mast Cells Kill Candida albicans in the Extracellular Environment but Spare Ingested Fungi from Death. Inflammation 2014; 37:2174-89. [DOI: 10.1007/s10753-014-9951-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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22
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Choi HW, Abraham SN. Mast cell mediator responses and their suppression by pathogenic and commensal microorganisms. Mol Immunol 2014; 63:74-9. [PMID: 24636146 DOI: 10.1016/j.molimm.2014.02.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 02/04/2014] [Indexed: 10/25/2022]
Abstract
Mast cells (MCs) are selectively found at the host environment interface and are capable of secreting a wide array of pharmacologically active mediators, many of which are prepackaged in granules. Over the past two decades, it has become clear that these cells have the capacity to recognize a range of infectious agents allowing them to play a key role in initiating and modulating early immune responses to infectious agents. However, a number of pathogenic and commensal microbes appear to have evolved distinct mechanisms to suppress MC mediator release to avoid elimination in the host. Understanding how these microbes suppress MC functions may have significant therapeutic value to relieve inflammatory disorders mediated by MCs.
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Affiliation(s)
- Hae Woong Choi
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| | - Soman N Abraham
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA; Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA; Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA; Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore.
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23
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Trivedi NH, Guentzel MN, Rodriguez AR, Yu JJ, Forsthuber TG, Arulanandam BP. Mast cells: multitalented facilitators of protection against bacterial pathogens. Expert Rev Clin Immunol 2013; 9:129-38. [PMID: 23390944 DOI: 10.1586/eci.12.95] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Mast cells are crucial effector cells evoking immune responses against bacterial pathogens. The positioning of mast cells at the host-environment interface, and the multitude of pathogen-recognition receptors and preformed mediator granules make these cells potentially the earliest to respond to an invading pathogen. In this review, the authors summarize the receptors used by mast cells to recognize invading bacteria and discuss the function of immune mediators released by mast cells in control of bacterial infection. The interaction of mast cells with other immune cells, including macrophages, dendritic cells and T cells, to induce protective immunity is highlighted. The authors also discuss mast cell-based vaccine strategies and the potential application in control of bacterial disease.
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Affiliation(s)
- Nikita H Trivedi
- South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
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24
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Reid-Yu SA, Small CLN, Coombes BK. CD3⁻NK1.1⁺ cells aid in the early induction of a Th1 response to an attaching and effacing enteric pathogen. Eur J Immunol 2013; 43:2638-49. [PMID: 23775576 DOI: 10.1002/eji.201343435] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 05/24/2013] [Accepted: 06/11/2013] [Indexed: 11/06/2022]
Abstract
Extracellular attaching and effacing (A/E) pathogens including pathogenic Escherichia coli colonize the host gut causing diarrhea and inflammation. Although much is known regarding the pathogenesis of A/E bacteria, there remains an incomplete understanding of host immune responses to these microbes. NK cells are an important source of IFN-γ and are essential for early innate responses to viral pathogens; however, their role during extracellular bacterial infections is still largely unexplored. We studied the host response to the murine A/E pathogen Citrobacter rodentium to investigate NK-cell function during infection. NK1.1⁺ cell depletions and analysis of colonic intestinal inflammation following Citrobacter infection demonstrated that CD3⁻NK1.1⁺ cells play an important role in the initial clearance of C. rodentium, as evidenced by higher bacterial load, intestinal pathology, and crypt hyperplasia at the peak of inflammation in depleted mice. Loss of CD3⁻NK1.1⁺ cells resulted in lower colonic IFN-γ, TNF-α, and IL-12, and a delay in homing of IFN-γ⁺CD4⁺ T cells to the gut. Loss of this response resulted in lower anti-C. rodentium IgG in NK1.1-depleted mice. These data establish that CD3⁻NK1.1⁺ cells are critical for inducing an early Th1 response involved in clearance of a pathogen that is restricted to the gastrointestinal tract.
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Affiliation(s)
- Sarah A Reid-Yu
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
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25
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A family of indoles regulate virulence and Shiga toxin production in pathogenic E. coli. PLoS One 2013; 8:e54456. [PMID: 23372726 PMCID: PMC3553163 DOI: 10.1371/journal.pone.0054456] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 12/11/2012] [Indexed: 11/29/2022] Open
Abstract
Enteropathogenic Escherichia coli (EPEC), enterohemorrhagic E. coli (EHEC) and enteroaggregative E. coli (EAEC) are intestinal pathogens that cause food and water-borne disease in humans. Using biochemical methods and NMR-based comparative metabolomics in conjunction with the nematode Caenorhabditis elegans, we developed a bioassay to identify secreted small molecules produced by these pathogens. We identified indole, indole-3-carboxaldehyde (ICA), and indole-3-acetic acid (IAA), as factors that only in combination are sufficient to kill C. elegans. Importantly, although lethal to C. elegans, these molecules downregulate several bacterial processes important for pathogenesis in mammals. These include motility, biofilm formation and production of Shiga toxins. Some pathogenic E. coli strains are known to contain a Locus of Enterocyte Effacement (LEE), which encodes virulence factors that cause “attaching and effacing” (A/E) lesions in mammals, including formation of actin pedestals. We found that these indole derivatives also downregulate production of LEE virulence factors and inhibit pedestal formation on mammalian cells. Finally, upon oral administration, ICA inhibited virulence and promoted survival in a lethal mouse infection model. In summary, the C. elegans model in conjunction with metabolomics has facilitated identification of a family of indole derivatives that broadly regulate physiology in E. coli, and virulence in pathogenic strains. These molecules may enable development of new therapeutics that interfere with bacterial small-molecule signaling.
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26
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New insights into the role of mast cells in autoimmunity: evidence for a common mechanism of action? Biochim Biophys Acta Mol Basis Dis 2011; 1822:57-65. [PMID: 21354470 DOI: 10.1016/j.bbadis.2011.02.009] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 02/17/2011] [Indexed: 11/20/2022]
Abstract
Mast cells are classically considered innate immune cells that act as first responders in many microbial infections and have long been appreciated as potent contributors to allergic reactions. However, recent advances in the realm of autoimmunity have made it clear that these cells are also involved in the pathogenic responses that exacerbate disease. In the murine models of multiple sclerosis, rheumatoid arthritis and bullous pemphigoid, both the pathogenic role of mast cells and some of their mechanisms of action are shared. Similar to their role in infection and a subset of allergic responses, mast cells are required for the efficient recruitment of neutrophils to sites of inflammation. Although this mast cell-dependent neutrophil response is protective in infection settings, it is postulated that neutrophils promote local vascular permeability and facilitate the entry of inflammatory cells that enhance tissue destruction at target sites. However, there is still much to learn. There is little information regarding mechanisms of mast cell activation in disease. Nor is it known how many mast cell-derived mediators are relevant and whether interactions with other cells are implicated in these diseases including T cells, B cells and astrocytes. Here we review the current state of knowledge about mast cells in autoimmune disease. We also discuss findings regarding newly discovered mast cell actions and factors that modulate mast cell function. We speculate that much of this new information will ultimately contribute to a greater understanding of the full range of mast cell actions in autoimmunity. This article is part of a Special Issue entitled: Mast cells in inflammation.
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27
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Shelburne CP, Abraham SN. The mast cell in innate and adaptive immunity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 716:162-85. [PMID: 21713657 DOI: 10.1007/978-1-4419-9533-9_10] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mast cells (MCs) were once considered only as effector cells in pathogenic IgE- and IgG-mediated responses such as allergy. However, developments over the last 15 years have suggested that MCs have evolved in vertebrates as beneficial effector cells that are involved in the very first inflammatory responses generated during infection. This pro-inflammatory environment has been demonstrated to be important for initiating innate responses in many different models of infection and more recently, in the development of adaptive immunity as well. Interestingly this latter finding has led to the discovery that small MC-activating compounds can behave as adjuvants in vaccine formulations. Thus, our continued understanding of the MC in the context of infectious disease is likely to not only expand our scope of the MC in the normal processes of immunity, but provide new therapeutic targets to combat disease.
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28
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Albert EJ, Duplisea J, Dawicki W, Haidl ID, Marshall JS. Tissue eosinophilia in a mouse model of colitis is highly dependent on TLR2 and independent of mast cells. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 178:150-60. [PMID: 21224053 DOI: 10.1016/j.ajpath.2010.11.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 07/22/2010] [Accepted: 09/09/2010] [Indexed: 12/20/2022]
Abstract
The mechanisms initiating eosinophil influx into sites of inflammation have been well studied in allergic disease but are poorly understood in other settings. This study examined the roles of TLR2 and mast cells in eosinophil accumulation during a nonallergic model of eosinophilia-associated colitis. TLR2-deficient mice (TLR2(-/-)) developed a more severe colitis than wild-type mice in the dextran sodium sulfate (DSS) model. However, they had significantly fewer eosinophils in the submucosa of the cecum (P < 0.01) and mid-colon (P < 0.01) than did wild-type mice after DSS treatment. Decreased eosinophilia in TLR2(-/-) mice was associated with lower levels of cecal CCL11 (P < 0.01). Peritoneal eosinophils did not express TLR2 protein, but TLR2 ligand injection into the peritoneal cavity induced local eosinophil recruitment, indicating that TLR2 activation of other cell types can mediate eosinophil recruitment. After DSS treatment, mast cell-deficient (Kit(W-sh/W-sh)) mice had similar levels of intestinal tissue eosinophilia were observed as those in wild-type mice. However, mast cell-deficient mice were partially protected from DSS-induced weight loss, an effect that was reversed by mast cell reconstitution. Overall, this study indicates a critical role for indirect TLR2-dependent pathways, but not mast cells, in the generation of eosinophilia in the large intestine during experimental colitis and has important implications for the regulation of eosinophils at mucosal inflammatory sites.
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Affiliation(s)
- Eric J Albert
- Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
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29
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Mast cells: Emerging sentinel innate immune cells with diverse role in immunity. Mol Immunol 2010; 48:14-25. [DOI: 10.1016/j.molimm.2010.07.009] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2010] [Revised: 07/06/2010] [Accepted: 07/09/2010] [Indexed: 12/31/2022]
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30
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Matsui H, Sekiya Y, Takahashi T, Nakamura M, Imanishi K, Yoshida H, Murayama SY, Takahashi T, Tsuchimoto K, Uchiyama T, Ubukata K. Dermal mast cells reduce progressive tissue necrosis caused by subcutaneous infection with Streptococcus pyogenes in mice. J Med Microbiol 2010; 60:128-134. [PMID: 20884771 DOI: 10.1099/jmm.0.020495-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A single subcutaneous (s.c.) infection with 1×10(7) c.f.u. GAS472, a group A streptococcus (GAS) serotype M1 strain isolated from the blood of a patient suffering from streptococcal toxic shock syndrome, led to severe damage of striated muscle layers in the feet of mast cell (MC)-deficient WBB6F(1)-Kit(W)/Kit(W-v) (W/W(v)) mice 72 h after infection. In contrast, no damage was recognized in striated muscle layers in the feet of the control WBB6F(1)-Kit(+/+) (+/+) mice 72 h after infection. In addition, adoptively transferred MCs reduced progressive tissue necrosis of the feet of W/W(v) mice after infection. However, there was no significant difference in the mortality rates between the W/W(v) and +/+ mice, or between the human CD46-expressing transgenic (Tg) mouse bone marrow-derived cultured MC-reconstituted W/W(v) and non-Tg mouse bone marrow-derived cultured MC-reconstituted W/W(v) mice after infection. Consequently, although MCs can help to reduce the severity of necrosis of the feet caused by s.c. infection with GAS472, such reduction of tissue necrosis scarcely improves the mortality rates of these mice. Moreover, human CD46 does not play a crucial role in the MC-mediated innate immune defence against GAS infection.
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Affiliation(s)
- Hidenori Matsui
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Yukie Sekiya
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Tetsufumi Takahashi
- Center for Clinical Pharmacy and Clinical Sciences, School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Masahiko Nakamura
- Center for Clinical Pharmacy and Clinical Sciences, School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Ken'ichi Imanishi
- Department of Microbiology and Immunology, Tokyo Women's Medical University School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan
| | - Haruno Yoshida
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Somay Yamagata Murayama
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Takashi Takahashi
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Kanji Tsuchimoto
- Center for Clinical Pharmacy and Clinical Sciences, School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Takehiko Uchiyama
- College of Human Science, Tokiwa University, 1-430-1 Miwa, Mito-shi, Ibaraki 310-8585, Japan.,Department of Microbiology and Immunology, Tokyo Women's Medical University School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan
| | - Kimiko Ubukata
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
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Abstract
Although mast cells were discovered more than a century ago, their functions beyond their role in allergic responses remained elusive until recently. However, there is a growing appreciation that an important physiological function of these cells is the recognition of pathogens and modulation of appropriate immune responses. Because of their ability to instantly release several pro-inflammatory mediators from intracellular stores and their location at the host-environment interface, mast cells have been shown to be crucial for optimal immune responses during infection. Mast cells seem to exert these effects by altering the inflammatory environment after detection of a pathogen and by mobilizing various immune cells to the site of infection and to draining lymph nodes. Interestingly, the character and timing of these responses can vary depending on the type of pathogen stimulus, location of pathogen recognition and sensitization state of the responding mast cells. Recent studies using mast cell activators as effective vaccine adjuvants show the potential of harnessing these cells to confer protective immunity against microbial pathogens.
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Affiliation(s)
- Soman N Abraham
- Department of Immunology, Duke University Medical Center, Durham, North Carolina 27710, USA.
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32
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Gamma interferon produced by antigen-specific CD4+ T cells regulates the mucosal immune responses to Citrobacter rodentium infection. Infect Immun 2010; 78:2653-66. [PMID: 20351140 DOI: 10.1128/iai.01343-09] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Citrobacter rodentium, a murine model pathogen for enteropathogenic Escherichia coli, colonizes the surface of intestinal epithelial cells and causes mucosal inflammation. This bacterium is an ideal model for investigating pathogen-host immune interactions in the gut. It is well known that gene transcripts for Th1 cytokines are highly induced in colonic tissue from mice infected with C. rodentium. However, it remains to be seen whether the Th1 or Th2 cytokines produced by antigen-specific CD4(+) T cells provide effective regulation of the host immune defense against C. rodentium infection. To investigate the antigen-specific immune responses, C. rodentium expressing ovalbumin (OVA-C. rodentium), a model antigen, was generated and used to define antigen-specific responses under gamma interferon (IFN-gamma)-deficient or interleukin-4 (IL-4)-deficient conditions in vivo. The activation of antigen-specific CD4(+) T cells and macrophage phagocytosis were evaluated in the presence of IFN-gamma or IL-4 in vitro. IFN-gamma-deficient mice exhibited a loss of body weight and a higher bacterial concentration in feces during OVA-C. rodentium infection than C57BL/6 (wild type) or IL-4-deficient mice. This occurred through the decreased efficiency of macrophage phagocytosis and the activation of antigen-specific CD4(+) T cells. Furthermore, a deficiency in antigen-specific CD4(+) T-cell-expressed IFN-gamma led to a higher susceptibility to mucosal and gut-derived systemic OVA-C. rodentium infection. These results show that the IFN-gamma produced by antigen-specific CD4(+) T cells plays an important role in the defense against C. rodentium.
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33
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Infection of mast cells with live streptococci causes a toll-like receptor 2- and cell-cell contact-dependent cytokine and chemokine response. Infect Immun 2009; 78:854-64. [PMID: 19933827 DOI: 10.1128/iai.01004-09] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mast cells (MCs) are strongly implicated in immunity toward bacterial infection, but the molecular mechanisms by which MCs contribute to the host response are only partially understood. We addressed this issue by examining the direct effects of a Gram-positive pathogen, Streptococcus equi, on bone marrow-derived MCs (BMMCs). Ultrastructural analysis revealed extensive formation of dilated rough endoplasmic reticulum in response to bacterial infection, indicating strong induction of protein synthesis. However, the BMMCs did not show signs of extensive degranulation, and this was supported by only slow release of histamine in response to infection. Coculture of live bacteria with BMMCs caused a profound secretion of CCL2/MCP-1, CCL7/MCP-3, CXCL2/MIP-2, CCL5/RANTES, interleukin-4 (IL-4), IL-6, IL-12, IL-13, and tumor necrosis factor alpha, as shown by antibody-based cytokine/chemokine arrays and/or enzyme-linked immunosorbent assay. In contrast, heat-inactivated bacteria caused only minimal cytokine/chemokine release. The cytokine/chemokine responses were substantially attenuated in Toll-like receptor 2-deficient BMMCs and were strongly dependent on cell-cell contacts between bacteria and BMMCs. Gene chip microarray analysis confirmed a massively upregulated expression of the genes coding for the secreted cytokines and chemokines and also identified a pronounced upregulation of numerous additional genes, including transcription factors, signaling molecules, and proteases. Together, the present study outlines MC-dependent molecular events associated with Gram-positive infection and thus provides an advancement in our understanding of how MCs may contribute to host defense toward bacterial insults.
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34
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Nguyen HTT, Dalmasso G, Powell KR, Yan Y, Bhatt S, Kalman D, Sitaraman S, Merlin D. Pathogenic bacteria induce colonic PepT1 expression: an implication in host defense response. Gastroenterology 2009; 137:1435-47.e1-2. [PMID: 19549526 PMCID: PMC2757477 DOI: 10.1053/j.gastro.2009.06.043] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 05/12/2009] [Accepted: 06/11/2009] [Indexed: 01/03/2023]
Abstract
BACKGROUND & AIMS Expression of the di/tripeptide transporter PepT1 has been observed in the colon under inflammatory conditions; however, the inducing factors and underlying mechanisms remain unknown. Here, we address the effects of pathogenic bacteria on colonic PepT1 expression together with its functional consequences. METHODS Human colonic HT29-Cl.19A cells were infected with the attaching and effacing enteropathogenic Escherichia coli (EPEC). Wild-type and PepT1 transgenic mice or cultured colonic tissues derived from these mice were infected with Citrobacter rodentium, a murine attaching and effacing pathogen related to EPEC. RESULTS EPEC induced PepT1 expression and activity in HT29-Cl.19A cells by intimately attaching to host cells through lipid rafts. Induction of PepT1 expression by EPEC required the transcription factor Cdx2. PepT1 expression reduced binding of EPEC to lipid rafts, as well as activation of nuclear factor-kappaB and mitogen-activated protein kinase and production of interleukin-8. Accordingly, ex vivo and in vivo experiments revealed that C rodentium induced colonic PepT1 expression and that, compared with their wild-type counterparts, PepT1 transgenic mice infected with C rodentium exhibited decreased bacterial colonization, production of proinflammatory cytokines, and neutrophil infiltration into the colon. CONCLUSIONS Our findings demonstrate a molecular mechanism underlying the regulation of colonic PepT1 expression under pathologic conditions and reveal a novel role for PepT1 in host defense via its capacity to modulate bacterial-epithelial interactions and intestinal inflammation.
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Affiliation(s)
| | | | | | - Yutao Yan
- Department of Medicine, Emory University, Atlanta, GA 30322
| | - Shantanu Bhatt
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Daniel Kalman
- Department of Pathology, Emory University, Atlanta, GA 30322
| | | | - Didier Merlin
- Department of Medicine, Emory University, Atlanta, GA 30322
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35
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von Köckritz-Blickwede M, Nizet V. Innate immunity turned inside-out: antimicrobial defense by phagocyte extracellular traps. J Mol Med (Berl) 2009; 87:775-83. [PMID: 19444424 PMCID: PMC2707954 DOI: 10.1007/s00109-009-0481-0] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Revised: 04/15/2009] [Accepted: 04/23/2009] [Indexed: 12/13/2022]
Abstract
The formation of extracellular traps (ETs) by phagocytic cells has been recognized as a novel and important mechanism of the host innate immune response against infections. ETs are formed by different host immune cells such as neutrophils, mast cells, and eosinophils after stimulation with mitogens, cytokines, or pathogens themselves, in a process dependent upon induction of a reactive-oxygen-species-mediated signaling cascade. ETs consist of nuclear or mitochondrial DNA as a backbone with embedded antimicrobial peptides, histones, and cell-specific proteases and thereby provide a matrix to entrap and kill microbes and to induce the contact system. This review summarizes the latest research on ETs and their role in innate immunity and host innate defense. Attention is also given to mechanisms by which certain leading bacterial pathogens have evolved to avoid entrapment and killing in these specialized structures.
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36
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Seo JY, Kim DY, Lee YS, Ro JY. Cytokine production through PKC/p38 signaling pathways, not through JAK/STAT1 pathway, in mast cells stimulated with IFNgamma. Cytokine 2009; 46:51-60. [PMID: 19231233 DOI: 10.1016/j.cyto.2008.12.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Revised: 11/25/2008] [Accepted: 12/16/2008] [Indexed: 11/30/2022]
Abstract
IFNgamma is strongly related to mast cell-associated diseases. There are many reports that IFNgamma inhibits mast cell degranulation. However, inflammatory cytokine production in mast cells stimulated with IFNgamma has not yet been clearly investigated. Therefore, we aimed to investigate the signaling pathways of cytokine production in mast cells stimulated with IFNgamma. Human mast cell line (HMC)-1 or mouse bone marrow-derived mast cells (BMMCs) were stimulated with IFNgamma (100 units) for time periods indicated. Expressions of proteins and mRNAs of cytokines were determined by ELISA and RT-PCR, respectively, activities of MAP kinases, PKC, JAK1/2, and STAT1 on tyrosine 701 and serine 727 by immunoblotting, the DNA-binding activity of the transcription factors by electrophoretic mobility shift assay. IFNgamma-stimulated mast cells showed increase in expressions of proteins and mRNAs of inflammatory cytokines, phosphorylations of MAP kinases, PKCalpha and betaI, JAK1/2, and STAT1 on tyrosine 701 and serine 727. JAK inhibitor or PKC inhibitors inhibited the phosphorylations of p38 kinase, STAT1 on serine 727, and activities of NF-kappaB and AP-1 compared to IFNgamma stimulation alone. These data suggest that IFNgamma-stimulated mast cells induce productions of inflammatory cytokines through PKC/p38/NF-kappaB and AP-1 pathways, not through classical JAK/STAT1 pathway, in both mast cells.
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Affiliation(s)
- Jung Youn Seo
- Department of Pharmacology and Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, 300 Chunchun-dong Jangan-ku, Suwon 440-746, Republic of Korea
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37
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Interleukin-1 receptor signaling protects mice from lethal intestinal damage caused by the attaching and effacing pathogen Citrobacter rodentium. Infect Immun 2008; 77:604-14. [PMID: 19075023 DOI: 10.1128/iai.00907-08] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Enteropathogenic Escherichia coli, enterohemorrhagic E. coli, and Citrobacter rodentium are classified as attaching and effacing pathogens based on their ability to adhere to the intestinal epithelium via actin-filled membranous protrusions (pedestals). Infection of mice with C. rodentium causes a breach of the intestinal epithelial barrier, leading to colitis via a vigorous inflammatory response resulting in diarrhea and a protective antibody response that clears the pathogen. Here we show that interleukin-1 receptor (IL-1R) signaling protects mice following infection with C. rodentium. Upon infection, mice lacking the type I IL-1R exhibit increased mortality together with severe colitis characterized by intramural colonic bleeding and intestinal damage including gangrenous mucosal necrosis, phenotypes also evident in MyD88-deficient mice. However, unlike MyD88(-/-) mice, IL-1R(-/-) mice do not exhibit increased pathogen loads in the colon, delays in the recruitment of innate immune cells such as neutrophils, or defects in the capacity to replace damaged enterocytes. Further, we demonstrate that IL-1R(-/-) mice have an increased predisposition to intestinal damage caused by C. rodentium but not to that caused by chemical irritants, such as dextran sodium sulfate. Together, these data suggest that IL-1R signaling regulates the susceptibility of the intestinal epithelia to damage caused by C. rodentium.
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38
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Lebeis SL, Sherman MA, Kalman D. Protective and destructive innate immune responses to enteropathogenic Escherichia coli and related A/E pathogens. Future Microbiol 2008; 3:315-28. [DOI: 10.2217/17460913.3.3.315] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Enteropathogenic Escherichia coli, enterohemorrhagic E. coli (O157:H7) and Citrobacter rodentium are classified as attaching and effacing (A/E) pathogens based on their ability to adhere to intestinal epithelium, destroy microvilli and induce pedestal formation at the site of infection. A/E bacterial infections also cause acute diarrheal episodes and intestinal inflammation. The use of model systems has led to an understanding of the innate immune response to A/E pathogens. The innate immune system plays a protective role, initiating a productive antibody response, directly killing bacteria and inducing repair mechanisms following tissue damage caused by infection. However, hyperactivation of the innate immune system can have negative consequences, including exacerbated tissue destruction following neutrophil infiltration. Here we review how innate immune cell types, including neutrophils, macrophages and dendritic cells, orchestrate both protective and destructive responses. Such information is crucial for the development of therapeutics that can mitigate destructive inflammatory responses while accentuating those that are protective.
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Affiliation(s)
- Sarah L Lebeis
- Microbiology & Molecular Genetics Graduate Program, Emory University School of Medicine, 615 Michael Street, Whitehead Research Building #155, Atlanta, GA 30322, USA and, Department of Pathology & Laboratory Medicine, Emory University School of Medicine, 615 Michael Street, Whitehead Research Building #144, Atlanta, GA 30322, USA
| | - Melanie A Sherman
- Department of Pathology & Laboratory Medicine, Emory University School of Medicine, 615 Michael Street, Whitehead Research Building #144, Atlanta, GA 30322, USA
| | - Daniel Kalman
- Department of Pathology & Laboratory Medicine, Emory University School of Medicine, 615 Michael Street, Whitehead Research Building #144, Atlanta, GA 30322, USA
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39
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Phagocytosis-independent antimicrobial activity of mast cells by means of extracellular trap formation. Blood 2008; 111:3070-80. [PMID: 18182576 DOI: 10.1182/blood-2007-07-104018] [Citation(s) in RCA: 406] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
These days it has been increasingly recognized that mast cells (MCs) are critical components of host defense against pathogens. In this study, we have provided the first evidence that MCs can kill bacteria by entrapping them in extracellular structures similar to the extracellular traps described for neutrophils (NETs). We took advantage of the ability of MCs to kill the human pathogen Streptococcus pyogenes by a phagocytosis-independent mechanism in order to characterize the extracellular antimicrobial activity of MCs. Close contact of bacteria and MCs was required for full antimicrobial activity. Immunofluorescence and electron microscopy revealed that S pyogenes was entrapped by extracellular structures produced by MCs (MCETs), which are composed of DNA, histones, tryptase, and the antimicrobial peptide LL-37. Disruption of MCETs significantly reduced the antimicrobial effect of MCs, suggesting that intact extracellular webs are critical for effective inhibition of bacterial growth. Similar to NETs, production of MCETs was mediated by a reactive oxygen species (ROS)-dependent cell death mechanism accompanied by disruption of the nuclear envelope, which can be induced after stimulation of MCs with phorbol-12-myristate-13-acetate (PMA), H(2)O(2), or bacterial pathogens. Our study provides the first experimental evidence of antimicrobial extracellular traps formation by an immune cell population other than neutrophils.
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40
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Metz M, Siebenhaar F, Maurer M. Mast cell functions in the innate skin immune system. Immunobiology 2007; 213:251-60. [PMID: 18406371 DOI: 10.1016/j.imbio.2007.10.017] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Revised: 10/22/2007] [Accepted: 10/29/2007] [Indexed: 12/12/2022]
Abstract
Mast cells are not only potent effector cells in allergy, but are also important players in protective immune responses against pathogens. Most of our knowledge about mast cells in innate immunity is derived from models of sepsis, whereas their role in innate immune responses of the skin has largely been neglected in the past. Their particular pattern of distribution in the skin and their ability to sense and react to pathogens and other danger signals indicate that mast cells can be important sentinels and effector cells in skin immune responses. The recent findings reviewed here have confirmed this hypothesis and have established a prominent role for skin mast cells in innate immunity.
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Affiliation(s)
- Martin Metz
- Department of Dermatology and Allergy, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
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41
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Algood HMS, Gallo-Romero J, Wilson KT, Peek RM, Cover TL. Host response to Helicobacter pylori infection before initiation of the adaptive immune response. ACTA ACUST UNITED AC 2007; 51:577-86. [PMID: 17919297 DOI: 10.1111/j.1574-695x.2007.00338.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Helicobacter pylori persistently colonizes the human stomach. In this study, immune responses to H. pylori that occur in the early stages of infection were investigated. Within the first 2 days after orogastric infection of mice with H. pylori, there was a transient infiltration of macrophages and neutrophils into the glandular stomach. By day 10 postinfection, the numbers of macrophages and neutrophils decreased to baseline levels. By 3 weeks postinfection, an adaptive immune response was detected, marked by gastric infiltration of T lymphocytes, macrophages, and neutrophils, as well as increased numbers of H. pylori-specific T cells, macrophages, and dendritic cells in paragastric lymph nodes. Neutrophil-attracting and macrophage-attracting chemokines were expressed at higher levels in the stomachs of H. pylori-infected mice than in the stomachs of uninfected mice. Increased expression of TNFalpha and IFNgamma (Th1-type inflammatory cytokines) and IL-17 (a Th17-type cytokine) was detected in the stomachs of H. pylori-infected mice, but increased expression of IL-4 (a Th2-type cytokine) was not detected. These data indicate that a transient gastric inflammatory response to H. pylori occurs within the first few days after infection, before the priming of T cells and initiation of an adaptive immune response. It is speculated that inappropriate waning of the innate immune response during early stages of infection may be a factor that contributes to H. pylori persistence.
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Affiliation(s)
- Holly M Scott Algood
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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42
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Soule BP, Brown JM, Kushnir-Sukhov NM, Simone NL, Mitchell JB, Metcalfe DD. Effects of Gamma Radiation on FcεRI and TLR-Mediated Mast Cell Activation. THE JOURNAL OF IMMUNOLOGY 2007; 179:3276-86. [PMID: 17709544 DOI: 10.4049/jimmunol.179.5.3276] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Ionizing gamma radiation has several therapeutic indications including bone marrow transplantation and tumor ablation. Among immune cells, susceptibility of lymphocytes to gamma radiation is well known. However, there is little information on the effects of gamma radiation on mast cells, which are important in both innate and acquired immunity. Previous studies have suggested that mast cells may release histamine in response to high doses of gamma radiation, whereas other reports suggest that mast cells are relatively radioresistant. No strong link has been established between gamma radiation and its effect on mast cell survival and activation. We examined both human and murine mast cell survival and activation, including mechanisms related to innate and acquired immune responses following gamma radiation. Data revealed that human and murine mast cells were resistant to gamma radiation-induced cytotoxicity and, importantly, that irradiation did not directly induce beta-hexosaminidase release. Instead, a transient attenuation of IgE-mediated beta-hexosaminidase release and cytokine production was observed which appeared to be the result of reactive oxygen species formation after irradiation. Mast cells retained the ability to phagocytose Escherichia coli particles and respond to TLR ligands as measured by cytokine production after irradiation. In vivo, there was no decrease in mast cell numbers in skin of irradiated mice. Additionally, mast cells retained the ability to respond to Ag in vivo as measured by passive cutaneous anaphylaxis in mice after irradiation. Mast cells are thus resistant to the cytotoxic effects and alterations in function after irradiation and, despite a transient inhibition, ultimately respond to innate and acquired immune activation signals.
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Affiliation(s)
- Benjamin P Soule
- Radiation Biology Branch, National Cancer Institute, National Institutes of Health, 10 Center Drive, Bethesda, MD 20892, USA
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43
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Lebeis SL, Bommarius B, Parkos CA, Sherman MA, Kalman D. TLR signaling mediated by MyD88 is required for a protective innate immune response by neutrophils to Citrobacter rodentium. THE JOURNAL OF IMMUNOLOGY 2007; 179:566-77. [PMID: 17579078 DOI: 10.4049/jimmunol.179.1.566] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Enteropathogenic Escherichia coli, enterohemorrhagic E. coli, and Citrobacter rodentium are classified as attaching and effacing pathogens based on their ability to adhere to intestinal epithelium via actin-filled membranous protrusions (pedestals). Infection of mice with C. rodentium causes breach of the colonic epithelial barrier, a vigorous Th1 inflammatory response, and colitis. Ultimately, an adaptive immune response leads to clearance of the bacteria. Whereas much is known about the adaptive response to C. rodentium, the role of the innate immune response remains unclear. In this study, we demonstrate for the first time that the TLR adaptor MyD88 is essential for survival and optimal immunity following infection. MyD88(-/-) mice suffer from bacteremia, gangrenous mucosal necrosis, severe colitis, and death following infection. Although an adaptive response occurs, MyD88-dependent signaling is necessary for efficient clearance of the pathogen. Based on reciprocal bone marrow transplants in conjunction with assessment of intestinal mucosal pathology, repair, and cytokine production, our findings suggest a model in which TLR signaling in hemopoietic and nonhemopoietic cells mediate three distinct processes: 1) induction of an epithelial repair response that maintains the protective barrier and limits access of bacteria to the lamina propria; 2) production of KC or other chemokines that attract neutrophils and thus facilitate killing of bacteria; and 3) efficient activation of an adaptive response that facilitates Ab-mediated clearance of the infection. Taken together, these experiments provide evidence for a protective role of innate immune signaling in infections caused by attaching and effacing pathogens.
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Affiliation(s)
- Sarah L Lebeis
- Microbiology and Molecular Genetics Graduate Program, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, 165 Michael Street, Atlanta, GA 30322, USA
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44
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Heib V, Becker M, Warger T, Rechtsteiner G, Tertilt C, Klein M, Bopp T, Taube C, Schild H, Schmitt E, Stassen M. Mast cells are crucial for early inflammation, migration of Langerhans cells, and CTL responses following topical application of TLR7 ligand in mice. Blood 2007; 110:946-53. [PMID: 17446350 DOI: 10.1182/blood-2006-07-036889] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Abstract
Until recently, IgE-activated mast cells have been regarded merely as effector cells of adaptive immune responses, involved in allergic reactions and mucosal immunity to parasites. Herein, we report that murine dermal mast cells, activated by local administration of a cream containing the synthetic TLR7 ligand imiquimod, are essential to initiate an early inflammatory reaction. The mast-cell–derived cytokines TNF-α and IL-1β play an important role in this process. Furthermore, TLR7-activated mast cells are also able to promote the emigration of Langerhans cells, which partly depends on the expression of mast-cell–derived IL-1β. We have previously shown that TLR7 ligation enhances transcutaneous immunization evoked by topical application of vaccine antigens to the skin, a procedure that directly targets skin-resident antigen-presenting cells. Consequently, we now demonstrate here that the capacity to mount a peptide-specific cytotoxic T-lymphocyte response following transcutaneous immunization using imiquimod as adjuvant is severely impaired in mast-cell–deficient mice. Thus, these findings demonstrate the potent versability of alternatively activated mast cells at the interface of innate and adaptive immunity.
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Affiliation(s)
- Valeska Heib
- Institute for Immunology, University of Mainz, Mainz, Germany
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45
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Borenshtein D, Nambiar PR, Groff EB, Fox JG, Schauer DB. Development of fatal colitis in FVB mice infected with Citrobacter rodentium. Infect Immun 2007; 75:3271-81. [PMID: 17470543 PMCID: PMC1932959 DOI: 10.1128/iai.01810-06] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 01/03/2007] [Accepted: 04/18/2007] [Indexed: 12/27/2022] Open
Abstract
Citrobacter rodentium is the causative agent of transmissible murine colonic hyperplasia. The disease is characterized by severe but temporary epithelial hyperplasia with limited inflammation in the descending colon of adult mice on a variety of genetic backgrounds. The natural history of infection with this murine pathogen has been characterized in outbred Swiss Webster (SW) mice but not in the cognate inbred FVB strain. In contrast to subclinical infection in SW mice, 12-week-old FVB mice developed overt disease with significant weight loss and mortality beginning by 9 days postinoculation (dpi). By 21 dpi, more than 75% of infected FVB mice died or had to be euthanized, whereas no mortality developed in SW mice. Mortality in FVB mice was fully prevented by fluid therapy. Fecal shedding of bacteria was similar in both groups through 9 dpi; however, a slight but significant delay in bacterial clearance was observed in FVB mice by 12 to 18 dpi. SW mice developed hyperplasia with minimal inflammation in the descending colon. FVB mice developed epithelial cell hyperproliferation, severe inflammation with erosions and ulcers, and epithelial atypia by 6 dpi in the descending colon. In the majority of surviving FVB mice, colonic lesions, including epithelial atypia, were reversible, although a small percentage (5 to 7%) exhibited chronic colitis through 7 months postinoculation. The existence of susceptible and resistant lines of mice with similar genetic backgrounds will facilitate the identification of host factors responsible for the outcome of infection and may lead to the development of novel strategies for preventing and treating infectious colitis.
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Affiliation(s)
- Diana Borenshtein
- Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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46
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Dawicki W, Marshall JS. New and emerging roles for mast cells in host defence. Curr Opin Immunol 2007; 19:31-8. [PMID: 17126541 DOI: 10.1016/j.coi.2006.11.006] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2006] [Accepted: 11/15/2006] [Indexed: 12/21/2022]
Abstract
Mast cells are highly effective sentinel cells, found close to blood vessels and especially common sites of potential infection, such as the skin, airways and gastrointestinal tract. Mast cells participate actively in the innate immune responses to many pathogens through a broad spectrum of mediators that can be selectively generated. They also have a role as innate effector cells in enhancing the earliest processes in the development of acquired immune responses. Studies of bacterial and parasitic models have revealed mast cell dependent regulation of effector cell recruitment, mucosal barrier function and lymph node hypertrophy. An important role for mast cells in viral infection is also implied by several in vivo and in vitro studies. There are multiple direct and indirect pathways by which mast cells can be selectively activated by pathogens including Toll-like receptors, co-receptors and complement component receptors. Understanding the mechanisms and scope of the contribution of mast cells to host defence will be crucial to regulating their activity therapeutically.
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Affiliation(s)
- Wojciech Dawicki
- Dalhousie University, 5850 College Street, Halifax, Nova Scotia, B3H 1X5, Canada
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Talero E, Sánchez-Fidalgo S, Calvo JR, Motilva V. Chronic administration of galanin attenuates the TNBS-induced colitis in rats. ACTA ACUST UNITED AC 2007; 141:96-104. [PMID: 17331599 DOI: 10.1016/j.regpep.2006.12.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 12/14/2006] [Accepted: 12/21/2006] [Indexed: 02/06/2023]
Abstract
Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disorder considered as a consequence of an aberrant response of the immune system to luminal antigens. Numerous groups of agents are being evaluated as novel therapeutic approaches for its treatment; in this way, different peptides have emerged as potential candidates. Galanin is an active neuropeptide distributed in the central and periphery nervous systems although it has been also described having important autocrine and paracrine regulatory capacities with interesting inflammatory and immune properties. In this line, we have observed that galanin treatment has a significant preventive effect in the experimental trinitrobenzensulfonic acid (TNBS) acute model of inflammatory colitis. The aim of the present study was to investigate intensively the role played by the peptide in the evolution of the inflammatory pathology associated to IBD. Galanin (5 and 10 microg/kg/day) was administered i.p., daily, starting 24 h after TNBS instillation, and continuing for 14 and 21 days. The lesions were blindly scored according to macroscopic and histological analyses and quantified as ulcer index. The results demonstrated that chronic administration of galanin improved the colon injury than the TNBS induced. The study by Western-blotting of the expression of nitric oxide inducible enzyme (iNOS), as well as the total nitrite production (NO) assayed by Griess-reaction, showed significant reduction associated with peptide administration. The number of mast cells was also identified in histological preparations stained with toluidine blue and the results showed that samples from galanin treatment, mostly at 21 days, had increased the number of these cells and many of them had a degranulated feature. In conclusion, chronic administration of galanin is able to exert a beneficial effect in the animal model of IBD assayed improving the reparative process. Participation of nitric oxide pathways and mucosal mast cells can not be discarded.
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Affiliation(s)
- E Talero
- Department of Pharmacology, School of Pharmacy, University of Seville, C. Prof. Garcia Gonzalez no. 2, 41012 Seville, Spain
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Abstract
Mouse models of intestinal inflammation have played a key role in understanding the mechanisms that govern the inflammatory response in the intestine, and in designing new therapeutic strategies in the treatment of patients with inflammatory bowel disease (IBD). Most of these models use chemical challenges, whereas relatively few robust models of intestinal inflammation caused by microbial infection are known. Two common models of infectious murine colitis and typhlitis are infection with the murine epithelial-adherent pathogen, Citrobacter rodentium, and infection of streptomycin-pretreated mice with Salmonella typhimurium. Studies in these models have helped to define the interactions between bacterial pathogens and host immune defenses, thus broadening the understanding of host-microbial interactions in the intestinal tract. Furthermore, such models help to determine the physiologic consequences of neutralizing specific mediators and signaling pathways implicated in inflammation on antimicrobial host defense.
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Affiliation(s)
- Lars Eckmann
- University of California-San Diego, Department of Medicine 0665, 9500 Gilman Drive, La Jolla, CA 92093-0665, USA.
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Abstract
The major classes of enteric bacteria harbour a conserved core genomic structure, common to both commensal and pathogenic strains, that is most likely optimized to a life style involving colonization of the host intestine and transmission via the environment. In pathogenic bacteria this core genome framework is decorated with novel genetic islands that are often associated with adaptive phenotypes such as virulence. This classical genome organization is well illustrated by a group of extracellular enteric pathogens, which includes enteropathogenic Escherichia coli (EPEC), enterohaemorrhagic E. coli (EHEC) and Citrobacter rodentium, all of which use attaching and effacing (A/E) lesion formation as a major mechanism of tissue targeting and infection. Both EHEC and EPEC are poorly pathogenic in mice but infect humans and domestic animals. In contrast, C. rodentium is a natural mouse pathogen that is related to E. coli, hence providing an excellent in vivo model for A/E lesion forming pathogens. C. rodentium also provides a model of infections that are mainly restricted to the lumen of the intestine. The mechanism's by which the immune system deals with such infections has become a topic of great interest in recent years. Here we review the literature of C. rodentium from its emergence in the mid-1960s to the most contemporary reports of colonization, pathogenesis, transmission and immunity.
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Affiliation(s)
- Rosanna Mundy
- Centre for Molecular Microbiology and Infection, Division of Cell and Molecular Biology, Imperial College London SW7 2AZ, UK
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