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Das S, Sarkar A, Ryan KA, Fox S, Berger AH, Juncadella IJ, Bimczok D, Smythies LE, Harris PR, Ravichandran KS, Crowe SE, Smith PD, Ernst PB. Brain angiogenesis inhibitor 1 is expressed by gastric phagocytes during infection with Helicobacter pylori and mediates the recognition and engulfment of human apoptotic gastric epithelial cells. FASEB J 2014; 28:2214-24. [PMID: 24509909 DOI: 10.1096/fj.13-243238] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
After Helicobacter pylori infection in humans, gastric epithelial cells (GECs) undergo apoptosis due to stimulation by the bacteria or inflammatory cytokines. In this study, we assessed the expression and function of brain angiogenesis inhibitor 1 (BAI1) in the engulfment of apoptotic GECs using human tissue and cells. After induction of apoptosis by H. pylori or camptothecin, there was a 5-fold increase in the binding of apoptotic GECs to THP-1 cells or peripheral blood monocyte-derived macrophages as assayed by confocal microscopy or conventional and imaging flow cytometry. Binding was impaired 95% by pretreating apoptotic cells with annexin V, underscoring the requirement for phosphatidylserine recognition. The phosphatidylserine receptor BAI1 was expressed in human gastric biopsy specimens and gastric phagocytes. To confirm the role of BAI1 in apoptotic cell clearance, the functional domain of BAI1 was used as a competitive inhibitor or BAI1 expression was inhibited by small interfering RNA. Both approaches decreased binding and engulfment >40%. Exposing THP-1 cells to apoptotic cells inhibited IL-6 production from 1340 to <364 pg/ml; however, this decrease was independent of phagocytosis. We conclude that recognition of apoptotic cells by BAI1 contributes to their clearance in the human gastric mucosa and this is associated with anti-inflammatory effects.
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Affiliation(s)
- Soumita Das
- 2Division of Comparative Pathology and Medicine, Department of Pathology, MC 0063, University of California, San Diego, San Diego, CA 92093-0063, USA.
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102
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Zhou D, Huang C, Lin Z, Zhan S, Kong L, Fang C, Li J. Macrophage polarization and function with emphasis on the evolving roles of coordinated regulation of cellular signaling pathways. Cell Signal 2014; 26:192-7. [DOI: 10.1016/j.cellsig.2013.11.004] [Citation(s) in RCA: 393] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 11/01/2013] [Indexed: 02/06/2023]
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103
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Rőszer T, Menéndez-Gutiérrez MP, Cedenilla M, Ricote M. Retinoid X receptors in macrophage biology. Trends Endocrinol Metab 2013; 24:460-8. [PMID: 23701753 DOI: 10.1016/j.tem.2013.04.004] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/19/2013] [Accepted: 04/23/2013] [Indexed: 01/07/2023]
Abstract
Retinoid X receptors (RXRs) form a distinct and unique subclass within the nuclear receptor (NR) superfamily of ligand-dependent transcription factors. RXRs regulate a plethora of genetic programs, including cell differentiation, the immune response, and lipid and glucose metabolism. Recent advances reveal that RXRs are important regulators of macrophages, key players in inflammatory and metabolic disorders. This review outlines the versatility of RXR action in the control of macrophage gene transcription through its heterodimerization with other NRs or through RXR homodimerization. We also highlight the potential of RXR-controlled transcriptional programs as targets for the treatment of pathologies associated with altered macrophage function, such as atherosclerosis, insulin resistance, autoimmunity, and neurodegeneration.
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Affiliation(s)
- Tamás Rőszer
- Cardiovascular Development and Repair Department, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Melchor Fernández Almagro 3, 28029 Madrid, Spain
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104
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Owen JL, Mohamadzadeh M. Microbial activation of gut dendritic cells and the control of mucosal immunity. J Interferon Cytokine Res 2013. [PMID: 23962004 DOI: 10.1089/jlr.2013.0046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Current data support a role for gut colonization in maintaining balanced mucosal and systemic immune responses and have suggested aberrant innate immune recognition of enteric bacteria as an initiator of the adaptive immune damage associated with inflammatory bowel disease (Crohn's disease and ulcerative colitis). In fact, data from human studies and experimental mouse models have implicated transformation of the gut microbiota from a beneficial symbiotic state to one of imbalance or "dysbiosis" in the pathogenesis of several autoinflammatory diseases, including allergic skin and respiratory disorders, rheumatoid arthritis, type I diabetes, and colorectal cancer. The host has evolved to co-exist and maintain a mutualistic relationship with the commensal microbes of the gut, and it is the function of the host innate immune system to initiate and maintain this homeostasis, while retaining the ability to respond appropriately to pathogenic organisms. In this review, we discuss the molecular and cellular interactions of the mucosal immune system that decide this delicate balance of mutualism. Furthermore, we will highlight the role of dendritic cells in preserving this precarious balance and how gene products of commensal microbes may play an integral role in re-establishing this balance once it has gone awry.
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Affiliation(s)
- Jennifer L Owen
- 1 Department of Infectious Diseases and Pathology, University of Florida , Gainesville, Florida
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105
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Owen JL, Mohamadzadeh M. Microbial activation of gut dendritic cells and the control of mucosal immunity. J Interferon Cytokine Res 2013; 33:619-31. [PMID: 23962004 DOI: 10.1089/jir.2013.0046] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Current data support a role for gut colonization in maintaining balanced mucosal and systemic immune responses and have suggested aberrant innate immune recognition of enteric bacteria as an initiator of the adaptive immune damage associated with inflammatory bowel disease (Crohn's disease and ulcerative colitis). In fact, data from human studies and experimental mouse models have implicated transformation of the gut microbiota from a beneficial symbiotic state to one of imbalance or "dysbiosis" in the pathogenesis of several autoinflammatory diseases, including allergic skin and respiratory disorders, rheumatoid arthritis, type I diabetes, and colorectal cancer. The host has evolved to co-exist and maintain a mutualistic relationship with the commensal microbes of the gut, and it is the function of the host innate immune system to initiate and maintain this homeostasis, while retaining the ability to respond appropriately to pathogenic organisms. In this review, we discuss the molecular and cellular interactions of the mucosal immune system that decide this delicate balance of mutualism. Furthermore, we will highlight the role of dendritic cells in preserving this precarious balance and how gene products of commensal microbes may play an integral role in re-establishing this balance once it has gone awry.
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Affiliation(s)
- Jennifer L Owen
- 1 Department of Infectious Diseases and Pathology, University of Florida , Gainesville, Florida
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106
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Owen JL, Mohamadzadeh M. Microbial activation of gut dendritic cells and the control of mucosal immunity. J Interferon Cytokine Res 2013. [PMID: 23962004 DOI: 10.1089/jir.2013.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Current data support a role for gut colonization in maintaining balanced mucosal and systemic immune responses and have suggested aberrant innate immune recognition of enteric bacteria as an initiator of the adaptive immune damage associated with inflammatory bowel disease (Crohn's disease and ulcerative colitis). In fact, data from human studies and experimental mouse models have implicated transformation of the gut microbiota from a beneficial symbiotic state to one of imbalance or "dysbiosis" in the pathogenesis of several autoinflammatory diseases, including allergic skin and respiratory disorders, rheumatoid arthritis, type I diabetes, and colorectal cancer. The host has evolved to co-exist and maintain a mutualistic relationship with the commensal microbes of the gut, and it is the function of the host innate immune system to initiate and maintain this homeostasis, while retaining the ability to respond appropriately to pathogenic organisms. In this review, we discuss the molecular and cellular interactions of the mucosal immune system that decide this delicate balance of mutualism. Furthermore, we will highlight the role of dendritic cells in preserving this precarious balance and how gene products of commensal microbes may play an integral role in re-establishing this balance once it has gone awry.
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Affiliation(s)
- Jennifer L Owen
- 1 Department of Infectious Diseases and Pathology, University of Florida , Gainesville, Florida
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107
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Jacquelin S, Licata F, Dorgham K, Hermand P, Poupel L, Guyon E, Deterre P, Hume DA, Combadière C, Boissonnas A. CX3CR1 reduces Ly6Chigh-monocyte motility within and release from the bone marrow after chemotherapy in mice. Blood 2013; 122:674-83. [PMID: 23775714 DOI: 10.1182/blood-2013-01-480749] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The chemokine receptor CCR2 controls the release of Ly6C(high) monocytes from the bone marrow and their recruitment to sites of inflammation. A second chemokine receptor, CX3CR1, is differentially expressed on monocyte subsets. We examined the role of CX3CR1 in monocyte trafficking during the recovery phase after cyclophosphamide (CP)-induced myeloablation and observed that, in the absence of CCR2, Ly6C(high) monocytes accumulated in the bone marrow and peripheral reconstitution was severely impaired compared with wild-type (WT) mice. In contrast, in the absence of CX3CR1, Ly6C(high) monocytes accumulated less rapidly in the marrow but recovered faster in the blood and were more recruited into the spleen, suggesting an opposite action between CCR2 and CX3CR1 in myelorestoration. During the recovery phase, marrow medullar monocytes displayed lower CX3CR1 expression and reduced their adherence to coated CX3CL1. Intravital imaging of the bone marrow showed that CP treatment impacts monocyte trafficking between the parenchyma and the vasculature. Medullar monocytes in CX3CR1(-/-) mice and mice treated with a specific antagonist of CX3CR1 displayed increased mean velocity and displacement and a reduced arrest coefficient compared with WT mice. This study indicates that CX3CR1 reduces the motility of Ly6C(high) monocytes in the bone marrow and thereby controls their release.
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Affiliation(s)
- Sébastien Jacquelin
- INSERM UMR S945, Immunité et Infection, CHU Pitié-Salpêtrière, Paris, France
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108
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Hohenhaus DM, Schaale K, Le Cao KA, Seow V, Iyer A, Fairlie DP, Sweet MJ. An mRNA atlas of G protein-coupled receptor expression during primary human monocyte/macrophage differentiation and lipopolysaccharide-mediated activation identifies targetable candidate regulators of inflammation. Immunobiology 2013; 218:1345-53. [PMID: 23948647 DOI: 10.1016/j.imbio.2013.07.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 07/04/2013] [Accepted: 07/06/2013] [Indexed: 12/15/2022]
Abstract
G protein-coupled receptors (GPCRs) are among the most important targets in drug discovery. In this study, we used TaqMan Low Density Arrays to profile the full GPCR repertoire of primary human macrophages differentiated from monocytes using either colony stimulating factor-1 (CSF-1/M-CSF) (CSF-1 Mϕ) or granulocyte macrophage colony stimulating factor (GM-CSF) (GM-CSF Mϕ). The overall trend was a downregulation of GPCRs during monocyte to macrophage differentiation, but a core set of 10 genes (e.g. LGR4, MRGPRF and GPR143) encoding seven transmembrane proteins were upregulated, irrespective of the differentiating agent used. Several of these upregulated GPCRs have not previously been studied in the context of macrophage biology and/or inflammation. As expected, CSF-1 Mϕ and GM-CSF Mϕ exhibited differential inflammatory cytokine profiles in response to the Toll-like Receptor (TLR)4 agonist lipopolysaccharide (LPS). Moreover, 15 GPCRs were differentially expressed between these cell populations in the basal state. For example, EDG1 was expressed at elevated levels in CSF-1 Mϕ versus GM-CSF Mϕ, whereas the reverse was true for EDG6. 101 GPCRs showed differential regulation over an LPS time course, with 65 of these profiles being impacted by the basal differentiation state (e.g. GPRC5A, GPRC5B). Only 14 LPS-regulated GPCRs showed asynchronous behavior (divergent LPS regulation) with respect to differentiation status. Thus, the differentiation state primarily affects the magnitude of LPS-regulated expression, rather than causing major reprogramming of GPCR gene expression profiles. Several GPCRs showing differential profiles between CSF-1 Mϕ and GM-CSF Mϕ (e.g. P2RY8, GPR92, EMR3) have not been widely investigated in macrophage biology and inflammation. Strikingly, several closely related GPCRs displayed completely opposing patterns of regulation during differentiation and/or activation (e.g. EDG1 versus EDG6, LGR4 versus LGR7, GPRC5A versus GPRC5B). We propose that selective regulation of GPCR5A and GPCR5B in CSF-1 Mϕ contributes to skewing toward the M2 macrophage phenotype. Our analysis of the GPCR repertoire expressed during primary human monocyte to macrophage differentiation and TLR4-mediated activation provides a valuable new platform for conducting future functional analyses of individual GPCRs in human macrophage inflammatory pathways.
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Affiliation(s)
- Daniel M Hohenhaus
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Qld 4072, Australia; Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Qld 4072, Australia
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109
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110
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Schönheit J, Kuhl C, Gebhardt M, Klett F, Riemke P, Scheller M, Huang G, Naumann R, Leutz A, Stocking C, Priller J, Andrade-Navarro M, Rosenbauer F. PU.1 Level-Directed Chromatin Structure Remodeling at the Irf8 Gene Drives Dendritic Cell Commitment. Cell Rep 2013; 3:1617-28. [DOI: 10.1016/j.celrep.2013.04.007] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 11/23/2012] [Accepted: 04/08/2013] [Indexed: 01/22/2023] Open
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111
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Hume DA, Mabbott N, Raza S, Freeman TC. Can DCs be distinguished from macrophages by molecular signatures? Nat Immunol 2013; 14:187-9. [PMID: 23416664 DOI: 10.1038/ni.2516] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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112
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Winnall WR, Hedger MP. Phenotypic and functional heterogeneity of the testicular macrophage population: a new regulatory model. J Reprod Immunol 2013; 97:147-58. [DOI: 10.1016/j.jri.2013.01.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Revised: 01/12/2013] [Accepted: 01/24/2013] [Indexed: 11/17/2022]
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113
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Sauter KA, Bouhlel MA, O’Neal J, Sester DP, Tagoh H, Ingram RM, Pridans C, Bonifer C, Hume DA. The function of the conserved regulatory element within the second intron of the mammalian Csf1r locus. PLoS One 2013; 8:e54935. [PMID: 23383005 PMCID: PMC3561417 DOI: 10.1371/journal.pone.0054935] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 12/18/2012] [Indexed: 01/09/2023] Open
Abstract
The gene encoding the receptor for macrophage colony-stimulating factor (CSF-1R) is expressed exclusively in cells of the myeloid lineages as well as trophoblasts. A conserved element in the second intron, Fms-Intronic Regulatory Element (FIRE), is essential for macrophage-specific transcription of the gene. However, the molecular details of how FIRE activity is regulated and how it impacts the Csf1r promoter have not been characterised. Here we show that agents that down-modulate Csf1r mRNA transcription regulated promoter activity altered the occupancy of key FIRE cis-acting elements including RUNX1, AP1, and Sp1 binding sites. We demonstrate that FIRE acts as an anti-sense promoter in macrophages and reversal of FIRE orientation within its native context greatly reduced enhancer activity in macrophages. Mutation of transcription initiation sites within FIRE also reduced transcription. These results demonstrate that FIRE is an orientation-specific transcribed enhancer element.
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Affiliation(s)
- Kristin A. Sauter
- Developmental Biology, The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, United Kingdom
| | - M. Amine Bouhlel
- Section of Experimental Haematology, Leeds Institute of Molecular Medicine, University of Leeds, St James’s University Hospital, Leeds, United Kingdom
| | - Julie O’Neal
- Developmental Biology, The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, United Kingdom
| | - David P. Sester
- Developmental Biology, The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, United Kingdom
| | - Hiromi Tagoh
- Section of Experimental Haematology, Leeds Institute of Molecular Medicine, University of Leeds, St James’s University Hospital, Leeds, United Kingdom
| | - Richard M. Ingram
- Section of Experimental Haematology, Leeds Institute of Molecular Medicine, University of Leeds, St James’s University Hospital, Leeds, United Kingdom
| | - Clare Pridans
- Developmental Biology, The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, United Kingdom
| | - Constanze Bonifer
- Section of Experimental Haematology, Leeds Institute of Molecular Medicine, University of Leeds, St James’s University Hospital, Leeds, United Kingdom
- School of Cancer Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - David A. Hume
- Developmental Biology, The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, United Kingdom
- * E-mail:
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114
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Stenmark KR, Yeager ME, El Kasmi KC, Nozik-Grayck E, Gerasimovskaya EV, Li M, Riddle SR, Frid MG. The adventitia: essential regulator of vascular wall structure and function. Annu Rev Physiol 2012; 75:23-47. [PMID: 23216413 PMCID: PMC3762248 DOI: 10.1146/annurev-physiol-030212-183802] [Citation(s) in RCA: 273] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The vascular adventitia acts as a biological processing center for the retrieval, integration, storage, and release of key regulators of vessel wall function. It is the most complex compartment of the vessel wall and is composed of a variety of cells, including fibroblasts, immunomodulatory cells (dendritic cells and macrophages), progenitor cells, vasa vasorum endothelial cells and pericytes, and adrenergic nerves. In response to vascular stress or injury, resident adventitial cells are often the first to be activated and reprogrammed to influence the tone and structure of the vessel wall; to initiate and perpetuate chronic vascular inflammation; and to stimulate expansion of the vasa vasorum, which can act as a conduit for continued inflammatory and progenitor cell delivery to the vessel wall. This review presents the current evidence demonstrating that the adventitia acts as a key regulator of vascular wall function and structure from the outside in.
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Affiliation(s)
- Kurt R. Stenmark
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Michael E. Yeager
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Karim C. El Kasmi
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Eva Nozik-Grayck
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | | | - Min Li
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Suzette R. Riddle
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
| | - Maria G. Frid
- University of Colorado Denver, Division of Pediatric Critical Care, Aurora, CO 80045
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115
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Haugland GT, Jordal AEO, Wergeland HI. Characterization of small, mononuclear blood cells from salmon having high phagocytic capacity and ability to differentiate into dendritic like cells. PLoS One 2012; 7:e49260. [PMID: 23166624 PMCID: PMC3498127 DOI: 10.1371/journal.pone.0049260] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 10/04/2012] [Indexed: 12/16/2022] Open
Abstract
Phagocytes are the principal component of the innate immune system, playing a key role in the clearance of foreign particles that include potential pathogens. In vertebrates, both neutrophils and mononuclear cells like monocytes, macrophages and dendritic cells are all professional phagocytes. In teleosts, B-lymphocytes also have potent phagocytic ability. We have isolated a population of small (<5 µm), mononuclear blood cells from Atlantic salmon (Salmo salar L.) not previously characterized. In order to identify them, we have performed morphological, gene expression, flow cytometry, cytochemical, ultrastructural and functional analyses. Interestingly, they highly express the gene encoding CD83, the most characteristic cell surface marker for dendritic cells in mammals, and MHC class II limited to professional antigen presenting cells. They did not express genes nor did they have cell markers for B-cells, T-cells, monocytes/macrophages or neutrophils as shown by qRT-PCR, flow cytometry and immunoblotting. A remarkable feature of these cells is their potent phagocytic capacity. Their oxygen-independent killing mechanism, as shown by intense acid phosphatase staining, is supported by lack of respiratory burst and myeloperoxidase activity and the acid phosphatase's sensitivity to tartrate. They show a high level of morphological plasticity, as, upon stimulation with mitogens, they change morphology and obtain branching protrusions similarly to dendritic cells. We suggest, based on our findings, that the small, round cells described here are progenitor cells with potential to differentiate into dendritic like cells, although we can not exclude the possibility that they represent a novel cell type.
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Affiliation(s)
- Gyri T Haugland
- Department of Biology, University of Bergen, Bergen High-Technology Centre, Bergen, Norway.
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116
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Colton CA. Immune heterogeneity in neuroinflammation: dendritic cells in the brain. J Neuroimmune Pharmacol 2012; 8:145-62. [PMID: 23114889 PMCID: PMC4279719 DOI: 10.1007/s11481-012-9414-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 10/22/2012] [Indexed: 12/20/2022]
Abstract
Dendritic cells (DC) are critical to an integrated immune response and serve as the key link between the innate and adaptive arms of the immune system. Under steady state conditions, brain DC’s act as sentinels, continually sampling their local environment. They share this function with macrophages derived from the same basic hemopoietic (bone marrow-derived) precursor and with parenchymal microglia that arise from a unique non-hemopoietic origin. While multiple cells may serve as antigen presenting cells (APCs), dendritic cells present both foreign and self-proteins to naïve T cells that, in turn, carry out effector functions that serve to protect or destroy. The resulting activation of the adaptive response is a critical step to resolution of injury or infection and is key to survival. In this review we will explore the critical roles that DCs play in the brain’s response to neuroinflammatory disease with emphasis on how the brain’s microenvironment impacts these actions.
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Affiliation(s)
- Carol A Colton
- Neurology, Duke University Medical Center, Box 2900, Durham, NC 27710, USA.
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117
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Gautier EL, Shay T, Miller J, Greter M, Jakubzick C, Ivanov S, Helft J, Chow A, Elpek KG, Gordonov S, Mazloom AR, Ma'ayan A, Chua WJ, Hansen TH, Turley SJ, Merad M, Randolph GJ. Gene-expression profiles and transcriptional regulatory pathways that underlie the identity and diversity of mouse tissue macrophages. Nat Immunol 2012; 13:1118-28. [PMID: 23023392 DOI: 10.1038/ni.2419] [Citation(s) in RCA: 1493] [Impact Index Per Article: 124.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 08/09/2012] [Indexed: 12/12/2022]
Abstract
We assessed gene expression in tissue macrophages from various mouse organs. The diversity in gene expression among different populations of macrophages was considerable. Only a few hundred mRNA transcripts were selectively expressed by macrophages rather than dendritic cells, and many of these were not present in all macrophages. Nonetheless, well-characterized surface markers, including MerTK and FcγR1 (CD64), along with a cluster of previously unidentified transcripts, were distinctly and universally associated with mature tissue macrophages. TCEF3, C/EBP-α, Bach1 and CREG-1 were among the transcriptional regulators predicted to regulate these core macrophage-associated genes. The mRNA encoding other transcription factors, such as Gata6, was associated with single macrophage populations. We further identified how these transcripts and the proteins they encode facilitated distinguishing macrophages from dendritic cells.
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Affiliation(s)
- Emmanuel L Gautier
- Department of Developmental and Regenerative Biology, Mount Sinai School of Medicine, New York, New York, USA
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118
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Hume DA. Plenary perspective: the complexity of constitutive and inducible gene expression in mononuclear phagocytes. J Leukoc Biol 2012; 92:433-44. [PMID: 22773680 DOI: 10.1189/jlb.0312166] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Monocytes and macrophages differentiate from progenitor cells under the influence of colony-stimulating factors. Genome-scale data have enabled the identification of the set of genes that distinguishes macrophages from other cell types and the ways in which thousands of genes are regulated in response to pathogen challenge. Although there has been a focus on a small subset of lineage-enriched transcription factors, such as PU.1, more than one-half of the transcription factors in the genome can be expressed in macrophage lineage cells under some state of activation, and they interact in a complex network. The network architecture is conserved across species, but many of the target genes evolve rapidly and differ between mouse and human. The data and publication deluge related to macrophage biology require the development of new analytical tools and ways of presenting information in an accessible form.
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Affiliation(s)
- David A Hume
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Scotland, United Kingdom.
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119
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Dynamic epigenetic enhancer signatures reveal key transcription factors associated with monocytic differentiation states. Blood 2012; 119:e161-71. [PMID: 22550342 DOI: 10.1182/blood-2012-01-402453] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cellular differentiation is orchestrated by lineage-specific transcription factors and associated with cell type-specific epigenetic signatures. In the present study, we used stage-specific, epigenetic "fingerprints" to deduce key transcriptional regulators of the human monocytic differentiation process. We globally mapped the distribution of epigenetic enhancer marks (histone H3 lysine 4 monomethylation, histone H3 lysine 27 acetylation, and the histone variant H2AZ), describe general properties of marked regions, and show that cell type-specific epigenetic "fingerprints" are correlated with specific, de novo-derived motif signatures at all of the differentiation stages studied (ie, hematopoietic stem cells, monocytes, and macrophages). We validated the novel, de novo-derived, macrophage-specific enhancer signature, which included ETS, CEBP, bZIP, EGR, E-Box and NF-κB motifs, by ChIP sequencing for a subset of motif corresponding transcription factors (PU.1, C/EBPβ, and EGR2), confirming their association with differentiation-associated epigenetic changes. We describe herein the dynamic enhancer landscape of human macrophage differentiation, highlight the power of genome-wide epigenetic profiling studies to reveal novel functional insights, and provide a unique resource for macrophage biologists.
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120
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Mouchemore KA, Pixley FJ. CSF-1 signaling in macrophages: pleiotrophy through phosphotyrosine-based signaling pathways. Crit Rev Clin Lab Sci 2012; 49:49-61. [DOI: 10.3109/10408363.2012.666845] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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121
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Lepur A, Carlsson MC, Novak R, Dumić J, Nilsson UJ, Leffler H. Galectin-3 endocytosis by carbohydrate independent and dependent pathways in different macrophage like cell types. Biochim Biophys Acta Gen Subj 2012; 1820:804-18. [PMID: 22450157 DOI: 10.1016/j.bbagen.2012.02.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 01/27/2012] [Accepted: 02/24/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND Galectin-3 (the Mac-2 antigen) is abundantly expressed in both macrophage like cells and certain non-macrophage cells. We have studied endocytosis of galectin-3 as one important step relevant for its function, and compared it between variants of a macrophage like cell line, and non-macrophage cells. METHODS Endocytosis of galectin-3 was observed by fluorescence microscopy and measured by flow cytometry. The endocytosis mechanism was analysed using galectin-3 mutants, galectin-3 inhibitors and endocytic pathways inhibitors in the human leukaemia THP-1 cell line differentiated into naïve (M0), classical (M1) or alternatively activated (M2) macrophage like cells, and the non-macrophage cell lines HFL-1 fibroblasts and SKBR3 breast carcinoma. RESULTS Galectin-3 endocytosis in non-macrophage cells and M2 cells was blocked by lactose and a potent galectin-3 inhibitor TD139, and also by the R186S mutation in the galectin-3 carbohydrate recognition domain (CRD). In M1 cells galectin-3 endocytosis could be inhibited only by chlorpromazine and by interference with the non-CRD N-terminal part of galectin-3. In all the cell types galectin-3 entered early endosomes within 5-10 min, to be subsequently targeted mainly to non-degradative vesicles, where it remained even after 24 h. CONCLUSIONS Galectin-3 endocytosis in M1 cells is receptor mediated and carbohydrate independent, while in M2 cells it is CRD mediated, although the non-CRD galectin-3 domain is also involved. General significance The demonstration that galectin-3 endocytosis in M1 macrophages is carbohydrate independent and different from M2 macrophages and non-macrophage cells, suggests novel, immunologically significant interactions between phagocytic cells, galectin-3 and its ligands.
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Affiliation(s)
- Adriana Lepur
- Section MIG (Microbiology, Immunology, Glycobiology), Department of Laboratory Medicine, Lund University, 223 62 Lund, Sweden.
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122
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Kapetanovic R, Fairbairn L, Beraldi D, Sester DP, Archibald AL, Tuggle CK, Hume DA. Pig bone marrow-derived macrophages resemble human macrophages in their response to bacterial lipopolysaccharide. THE JOURNAL OF IMMUNOLOGY 2012; 188:3382-94. [PMID: 22393154 DOI: 10.4049/jimmunol.1102649] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Mouse bone marrow-derived macrophages (BMDM) grown in M-CSF (CSF-1) have been used widely in studies of macrophage biology and the response to TLR agonists. We investigated whether similar cells could be derived from the domestic pig using human rCSF-1 and whether porcine macrophages might represent a better model of human macrophage biology. Cultivation of pig bone marrow cells for 5-7 d in presence of human rCSF-1 generated a pure population of BMDM that expressed the usual macrophage markers (CD14, CD16, and CD172a), were potent phagocytic cells, and produced TNF in response to LPS. Pig BMDM could be generated from bone marrow cells that had been stored frozen and thawed so that multiple experiments can be performed on samples from a single animal. Gene expression in pig BMDM from outbred animals responding to LPS was profiled using Affymetrix microarrays. The temporal cascade of inducible and repressible genes more closely resembled the known responses of human than mouse macrophages, sharing with humans the regulation of genes involved in tryptophan metabolism (IDO, KYN), lymphoattractant chemokines (CCL20, CXCL9, CXCL11, CXCL13), and the vitamin D3-converting enzyme, Cyp27B1. Conversely, in common with published studies of human macrophages, pig BMDM did not strongly induce genes involved in arginine metabolism, nor did they produce NO. These results establish pig BMDM as an alternative tractable model for the study of macrophage transcriptional control.
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Affiliation(s)
- Ronan Kapetanovic
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
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Martinez O, Leung LW, Basler CF. The role of antigen-presenting cells in filoviral hemorrhagic fever: gaps in current knowledge. Antiviral Res 2012; 93:416-28. [PMID: 22333482 PMCID: PMC3299938 DOI: 10.1016/j.antiviral.2012.01.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 01/26/2012] [Accepted: 01/30/2012] [Indexed: 12/01/2022]
Abstract
The filoviruses, Ebola virus (EBOV) and Marburg virus (MARV), are highly lethal zoonotic agents of concern as emerging pathogens and potential bioweapons. Antigen-presenting cells (APCs), particularly macrophages and dendritic cells, are targets of filovirus infection in vivo. Infection of these cell types has been proposed to contribute to the inflammation, activation of coagulation cascades and ineffective immune responses characteristic of filovirus hemorrhagic fever. However, many aspects of filovirus–APC interactions remain to be clarified. Among the unanswered questions: What determines the ability of filoviruses to replicate in different APC subsets? What are the cellular signaling pathways that sense infection and lead to production of copious quantities of cytokines, chemokines and tissue factor? What are the mechanisms by which innate antiviral responses are disabled by these viruses, and how may these mechanisms contribute to inadequate adaptive immunity? A better understanding of these issues will clarify the pathogenesis of filoviral hemorrhagic fever and provide new avenues for development of therapeutics.
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Affiliation(s)
- Osvaldo Martinez
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029, USA
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124
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Swiatczak B, Rescigno M. How the interplay between antigen presenting cells and microbiota tunes host immune responses in the gut. Semin Immunol 2012; 24:43-9. [DOI: 10.1016/j.smim.2011.11.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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125
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MacLellan LM, Montgomery J, Sugiyama F, Kitson SM, Thümmler K, Silverman GJ, Beers SA, Nibbs RJB, McInnes IB, Goodyear CS. Co-opting endogenous immunoglobulin for the regulation of inflammation and osteoclastogenesis in humans and mice. ACTA ACUST UNITED AC 2012; 63:3897-907. [PMID: 22127707 DOI: 10.1002/art.30629] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVE Cells of the monocytic lineage play fundamental roles in the regulation of health, ranging from the initiation and resolution of inflammation to bone homeostasis. In rheumatoid arthritis (RA), the inflamed synovium exhibits characteristic infiltration of macrophages along with local osteoclast maturation, which, together, drive chronic inflammation and downstream articular destruction. The aim of this study was to explore an entirely novel route of immunoglobulin-mediated regulation, involving simultaneous suppression of the inflammatory and erosive processes in the synovium. METHODS Using in vivo and in vitro studies of human cells and a murine model of RA, the ability of staphylococcal protein A (SPA) to interact with and modulate cells of the monocytic lineage was tested. In addition, the efficacy of SPA as a therapeutic agent was evaluated in murine collagen-induced arthritis (CIA). RESULTS SPA showed a capacity to appropriate circulating IgG, by generating small immunoglobulin complexes that interacted with monocytes, macrophages, and preosteoclasts. Formation of these complexes resulted in Fcγ receptor type I-dependent polarization of macrophages to a regulatory phenotype, rendering them unresponsive to activators such as interferon-γ. The antiinflammatory complexes also had the capacity to directly inhibit differentiation of preosteoclasts into osteoclasts in humans. Moreover, administration of SPA in the early stages of disease substantially alleviated the clinical and histologic erosive features of CIA in mice. CONCLUSION These findings demonstrate the overarching utility of immunoglobulin complexes for the prevention and treatment of inflammatory diseases. The results shed light on the interface between immunoglobulin complex-mediated pathways, osteoclastogenesis, and associated pathologic processes. Thus, therapeutic agents designed to harness all of these properties may be an effective treatment for arthritis, by targeting both the innate inflammatory response and prodestructive pathways.
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MESH Headings
- Animals
- Antigen-Antibody Complex/pharmacology
- Antigen-Antibody Complex/therapeutic use
- Antirheumatic Agents/pharmacology
- Antirheumatic Agents/therapeutic use
- Arthritis, Experimental/drug therapy
- Arthritis, Experimental/immunology
- Arthritis, Experimental/physiopathology
- Cell Differentiation/physiology
- Cell Proliferation
- Cells, Cultured
- Cytokines/physiology
- Disease Models, Animal
- Humans
- Immunoglobulins/physiology
- Immunoglobulins/therapeutic use
- Inflammation/drug therapy
- Inflammation/physiopathology
- Leukocytes, Mononuclear/cytology
- Leukocytes, Mononuclear/drug effects
- Leukocytes, Mononuclear/physiology
- Macrophages/cytology
- Macrophages/drug effects
- Macrophages/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Mice, Knockout
- Osteoclasts/cytology
- Osteoclasts/drug effects
- Osteoclasts/physiology
- Receptors, IgG/genetics
- Receptors, IgG/physiology
- Staphylococcal Protein A/pharmacology
- Staphylococcal Protein A/therapeutic use
- Stem Cells/cytology
- Stem Cells/drug effects
- Stem Cells/physiology
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Abstract
PURPOSE OF REVIEW This review focuses on comorbidities between nose and skin allergies. For this purpose, allergic rhinitis and chronic rhinosinusitis (CRS) were selected as examples of nasal disorders and atopic dermatitis and urticaria as examples of allergic skin disorders and the individual entities of both localizations were evaluated and compared in relation to their prevalence and coincidence, underlying pathophysiological mechanisms, genetic data and shared therapy options. RECENT FINDINGS The inter-relationships between atopic dermatitis and allergic rhinitis are the best studied, but even for the other comorbidities it was possible to demonstrate comparable pathomechanisms in addition to a high prevalence and coincidence, particularly in the case of atopically assisted forms. In this context, the interactions of IgE, mast cells and eosinophils play a special role, but genetic issues, the significance of epithelial barrier defects and colonization with Staphylococcus aureus are also important sharing issues. SUMMARY Allergic skin disorders such as atopic dermatitis and urticaria are frequently associated with comorbidities of the nose as well as allergic rhinitis and CRS. By contrast, different manifestations of these diseases involve the nose and the skin. These are not separate diseases but are linked by complex and currently unclear/insufficiently defined inter-relationships.
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Affiliation(s)
- Heidi Olze
- Department of Otorhinolaryngology, Charité - Universitätsmedizin Berlin, Campus Charité Mitte, Berlin, Germany.
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127
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Recent development of the mononuclear phagocyte system: in memory of Metchnikoff and Ehrlich on the 100th Anniversary of the 1908 Nobel Prize in Physiology or Medicine. Biol Cell 2012; 101:709-21. [DOI: 10.1042/bc20080227] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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128
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Bethunaickan R, Sahu R, Davidson A. Analysis of renal mononuclear phagocytes in murine models of SLE. Methods Mol Biol 2012; 900:207-32. [PMID: 22933071 DOI: 10.1007/978-1-60761-720-4_10] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In this chapter we present methods for the isolation and characterization of mononuclear phagocytes from the kidneys of mice with SLE. Activation of these cells is associated with the onset of clinical disease in mice and infiltration with these cells is associated with poor prognosis in humans. Using magnetic beads followed by flow cytometric sorting, pure populations of cells are obtained that are functional in a variety of assays. Sufficient numbers of cells are obtained for genomic characterization. An analysis of the function of these cells should lead to a better understanding of the inflammatory processes that cause renal impairment in SLE and other renal inflammatory diseases.
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Affiliation(s)
- Ramalingam Bethunaickan
- Center for Autoimmunity and Musculoskeletal Diseases, Feinstein Institute for Medical Research, Manhasset, New York, NY, USA
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129
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Abstract
Macrophages are a diverse phenotype of professional phagocytic cells derived from bone-marrow precursors and parent monocytes in the peripheral blood. They are essential for the maintenance and defence of host tissues, doing so by sensing and engulfing particulate matter and, when necessary, initiating a pro-inflammatory response. Playing such a vast number of roles in both health and disease, the activation phenotype of macrophages can vary greatly and is largely dependent on the surrounding microenvironment. These phenotypes can be mimicked in experimental macrophage models derived from monocytes and in conjunction with stimulatory factors, although given the complexity of in vivo tissue spaces these model cells are inherently imperfect. Furthermore, experimental observations generated in mice are not necessarily conserved in humans, which can hamper translational research. The following chapter aims to provide an overview of how macrophages and their parent cell-type, monocytes, are classified, their development through the myeloid lineage, and finally, the general function of macrophages.
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130
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Therapeutic applications of macrophage colony-stimulating factor-1 (CSF-1) and antagonists of CSF-1 receptor (CSF-1R) signaling. Blood 2011; 119:1810-20. [PMID: 22186992 DOI: 10.1182/blood-2011-09-379214] [Citation(s) in RCA: 506] [Impact Index Per Article: 38.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Macrophage-colony stimulating factor (CSF-1) signaling through its receptor (CSF-1R) promotes the differentiation of myeloid progenitors into heterogeneous populations of monocytes, macrophages, dendritic cells, and bone-resorbing osteoclasts. In the periphery, CSF-1 regulates the migration, proliferation, function, and survival of macrophages, which function at multiple levels within the innate and adaptive immune systems. Macrophage populations elicited by CSF-1 are associated with, and exacerbate, a broad spectrum of pathologies, including cancer, inflammation, and bone disease. Conversely, macrophages can also contribute to immunosuppression, disease resolution, and tissue repair. Recombinant CSF-1, antibodies against the ligand and the receptor, and specific inhibitors of CSF-1R kinase activity have been each been tested in a range of animal models and in some cases, in patients. This review examines the potential clinical uses of modulators of the CSF-1/CSF-1R system. We conclude that CSF-1 promotes a resident-type macrophage phenotype. As a treatment, CSF-1 has therapeutic potential in tissue repair. Conversely, inhibition of CSF-1R is unlikely to be effective in inflammatory disease but may have utility in cancer.
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131
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Samaan MC. The macrophage at the intersection of immunity and metabolism in obesity. Diabetol Metab Syndr 2011; 3:29. [PMID: 22035457 PMCID: PMC3223491 DOI: 10.1186/1758-5996-3-29] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Accepted: 10/28/2011] [Indexed: 12/23/2022] Open
Abstract
Obesity is a worldwide pandemic representing one of the major challenges that societies face around the globe. Identifying the mechanisms involved in its development and propagation will help the development of preventative and therapeutic strategies that may help control its rising rates.Obesity is associated with chronic low-grade inflammation, and this is believed to be one of the major contributors to the development of insulin resistance, which is an early event in obesity and leads to type 2 diabetes when the pancreas fails to keep up with increased demand for insulin. In this review, we discuss the role of macrophages in mediation of inflammation in obesity in metabolic organs including adipose tissue, skeletal muscle and liver. The presence of immune cells at the interface with metabolic organs modulates both metabolic function and inflammatory responses in these organs, and may provide a potential therapeutic target to modulate metabolic function in obesity.
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Affiliation(s)
- M Constantine Samaan
- Division of Pediatric Endocrinology, Department of Pediatrics, McMaster Children's Hospital, McMaster University, 1200 Main Street West, Hamilton, Ontario, Canada.
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132
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Mowat AM, Bain CC. Mucosal macrophages in intestinal homeostasis and inflammation. J Innate Immun 2011; 3:550-64. [PMID: 22025201 PMCID: PMC3224516 DOI: 10.1159/000329099] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Accepted: 05/04/2011] [Indexed: 12/17/2022] Open
Abstract
Intestinal macrophages are essential for local homeostasis and in keeping a balance between commensal microbiota and the host. However, they also play essential roles in inflammation and protective immunity, when they change from peaceful regulators to powerful aggressors. As a result, activated macrophages are important targets for treatment of inflammatory bowel diseases such as Crohn's disease. Until recently, the complexity and heterogeneity of intestinal macrophages have been underestimated and here we review current evidence that there are distinct populations of resident and inflammatory macrophages in the intestine. We describe the mechanisms that ensure macrophages remain partially inert in the healthy gut and cannot promote inflammation despite constant exposure to bacteria and other stimuli. This may be because the local environment 'conditions' macrophage precursors to become unresponsive after they arrive in the gut. Nevertheless, this permits some active, physiological functions to persist. A new population of pro-inflammatory macrophages appears in inflammation and we review the evidence that this involves recruitment of a distinct population of fully responsive monocytes, rather than alterations in the existing cells. A constant balance between these resident and inflammatory macrophages is critical for maintaining the status quo in healthy gut and ensuring protective immunity when required.
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Affiliation(s)
- Allan McI Mowat
- Institute of Infection, Immunology and Inflammation, University of Glasgow, Glasgow, UK.
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133
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Beitnes ACR, Ráki M, Lundin KEA, Jahnsen J, Sollid LM, Jahnsen FL. Density of CD163+ CD11c+ dendritic cells increases and CD103+ dendritic cells decreases in the coeliac lesion. Scand J Immunol 2011; 74:186-94. [PMID: 21392045 DOI: 10.1111/j.1365-3083.2011.02549.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Coeliac disease is a chronic inflammation of the intestinal mucosa controlled by gluten-specific T cells restricted by disease-associated HLA-DQ molecules. We have previously reported that mucosal CD11c(+) dendritic cells (DCs) are responsible for activation of gluten-reactive T cells within the coeliac lesion. In mice, intestinal CD11c(+) DCs comprise several functionally distinct subsets. Here, we report that HLA-DQ(+) antigen-presenting cells (APCs) in normal human duodenal mucosa can be divided into four subsets with striking similarities to those described in mice: CD163(+) CD11c(-) macrophages (74%), and CD11c(+) cells expressing either CD163 (7%), CD103 (11%) or CD1c (13%). CD103(+) and CD1c(+) DCs belonged to partly overlapping populations, whereas CD163(+) CD11c(+) APCs appeared to be a distinct population. In the coeliac lesion, we found increased density of CD163(+) CD11c(+) APCs, whereas the density of CD103(+) and CD1c(+) DCs was decreased, suggesting that distinct subpopulations of APCs in coeliac disease may exert different functions in the pathogenesis.
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Affiliation(s)
- A-C R Beitnes
- Centre for Immune Regulation, Institute of Immunology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
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134
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Defining the anatomical localisation of subsets of the murine mononuclear phagocyte system using integrin alpha X (Itgax, CD11c) and colony stimulating factor 1 receptor (Csf1r, CD115) expression fails to discriminate dendritic cells from macrophages. Immunobiology 2011; 216:1228-37. [PMID: 21885153 DOI: 10.1016/j.imbio.2011.08.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 08/12/2011] [Indexed: 01/22/2023]
Abstract
The murine mononuclear phagocyte (MNP) system comprises a diverse population of cells, including monocytes, dendritic cells (DC) and macrophages. Derived from the myeloid haematopoietic lineage, this group of cells express a variety of well characterized surface markers. Expression of the integrin alpha X (Itgax, CD11c) is commonly used to identify classical DC, and similarly expression of colony stimulating factor 1 receptor (Csf1r, CD115) to identify macrophages. We have characterized the expression of these markers using a variety of transgenic mouse models. We confirmed previous observations of Itgax expression in anatomically defined subsets of MNPs in secondary lymphoid organs, including all MNPs identified within the germinal centres. The majority of MNPs in the intestinal lamina propria and lung express Itgax. All mucosal Itgax expressing cells also express Csf1r suggesting Csf1-dependent haematopoietic derivation. This double-positive population included germinal centre MNPs. These data reveal that Itgax expression alone does not specifically define classical DC. These results suggest more cautious interpretation of Itgax-dependent experimentation and direct equation with uniquely DC-mediated activities, particularly in the functioning of non-lymphoid MNPs within the intestinal lamina propria.
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135
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Macrophages.com: an on-line community resource for innate immunity research. Immunobiology 2011; 216:1203-11. [PMID: 21924793 DOI: 10.1016/j.imbio.2011.07.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 07/18/2011] [Indexed: 01/03/2023]
Abstract
Macrophages play a major role in tissue remodelling during development, wound healing and tissue homeostasis, and are central to innate immunity and to the pathology of tissue injury and inflammation. Given this fundamental role in many aspects of biological function, an enormous wealth of information has accumulated on these fascinating cells in the literature and other public repositories. With the escalation of genome-scale data derived from macrophages and related haematopoietic cell types, there is a growing need for an integrated resource that seeks to compile, organise and analyse our collective knowledge of macrophage biology. Here we describe a community-driven web-based resource, macrophages.com that aims to provide a portal onto various types of Omics data to facilitate comparative genomic studies, promoter and transcriptional network analyses, models of macrophage pathways together with other information on these cells. To this end, the website combines public and in-house analyses of expression data with pre-analysed views of co-expressed genes as supported by the network analysis tool BioLayout Express(3D), as well as providing access to maps of pathways active in macrophages. Macrophages.com also provides access to an extensive image library of macrophages in adult/embryonic tissue sections prepared from normal and transgenic mice. In addition, the site links to the Human Protein Atlas database so as to provide direct access to protein expression patterns in human macrophages. Finally, an integrated gene-centric portal provides the tools for rapid promoter analysis studies based on a comprehensive set of CAGE-derived transcription start site (TSS) sequences in human and mouse genomes as generated by the Functional Annotation of Mammalian genomes (FANTOM) projects initiated by the RIKEN Omics Science Center. Our aim is to continue to grow the macrophages.com resource using publicly available data, as well as in-house generated knowledge. In so doing we aim to provide a user-friendly community website and a community portal for access to comprehensive sets of macrophage-related data.
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136
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Cavaillon JM. The historical milestones in the understanding of leukocyte biology initiated by Elie Metchnikoff. J Leukoc Biol 2011; 90:413-24. [PMID: 21628329 DOI: 10.1189/jlb.0211094] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Progress in science is made with key discoveries, correct analyses, wrong statements, and disputes within the scientific community. Despite scientific controversies, Elie Metchnikoff has allowed the theory of phagocytes to triumph. Starting his career as a zoologist, Metchnikoff became a pathologist, beautifully defining the role of monocytes, macrophages, and neutrophils during inflammation and innate immunity. The discoveries of immune cells were made by other outstandings scientists, such as Paul Ehrlich, whose key contributions to humoral immunity led him to share the Nobel Prize with Metchnikoff. Ludwig Aschoff grouped certain cells under the term RES, according to their propensity for absorbing and storing vital stains. This classification was not always a source of accurate discoveries, and research on the exact function of RES cells led to some wanderings. This is illustrated by studies about the nature of the antibody-producing cells, which were first thought to belong to the RES, before being identified as plasmocytes and lymphocytes.
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137
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de Souza Sales J, Lara FA, Amadeu TP, de Oliveira Fulco T, da Costa Nery JA, Sampaio EP, Pinheiro RO, Sarno EN. The role of indoleamine 2, 3-dioxygenase in lepromatous leprosy immunosuppression. Clin Exp Immunol 2011; 165:251-63. [PMID: 21592112 DOI: 10.1111/j.1365-2249.2011.04412.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
To elucidate further the possible role of the tryptophan, rate-limiting enzyme indoleamine 2, 3-dioxygenase (IDO) in leprosy, the distribution of IDO-positive cells and IDO activity in the skin biopsies and sera of these patients representing the entire spectrum of the disease were studied. An increased number of macrophages/dendritic cells (DC-lineage IDO(+) cells were found in lepromatous (LL) compared to tuberculoid (BT) and reversal reaction (RR) patients. IDO-positive cells showing CD68 and CD86 surface markers predominated in LL lesions, while higher levels of IDO activity were observed in the sera of LL versus BT patients. Tests revealed an increased IDO message in Mycobacterium leprae-stimulated peripheral blood mononuclear cells (PBMC) by real-time polymerase chain reaction (PCR) and increased IDO expression in M. leprae-stimulated CD14(+) cells of both healthy controls (HC) and LL patients, as evaluated via flow cytometry. Increased M. leprae-induced IDO-protein synthesis was also confirmed by Western blot. Based on our in vitro studies, it was confirmed that M. leprae up-regulated IDO expression and activity in HC and LL monocytes. Interferon (IFN)-γ synergized with M. leprae in promoting IDO expression and activity in monocytes. IDO expression induced by both IFN-γ and M. leprae was abrogated by 1-methyltryptophan (1-MT). Our data suggest that M. leprae chronic infection activates the suppressive molecule IDO which, in turn, contributes to the specific immunosuppression observed in LL leprosy.
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Affiliation(s)
- J de Souza Sales
- Leprosy Laboratory, Oswaldo Cruz Institute, Fiocruz - Rio de Janeiro, Brazil
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138
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Bethunaickan R, Berthier CC, Ramanujam M, Sahu R, Zhang W, Sun Y, Bottinger EP, Ivashkiv L, Kretzler M, Davidson A. A unique hybrid renal mononuclear phagocyte activation phenotype in murine systemic lupus erythematosus nephritis. THE JOURNAL OF IMMUNOLOGY 2011; 186:4994-5003. [PMID: 21411733 DOI: 10.4049/jimmunol.1003010] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Renal infiltration with mononuclear cells is associated with poor prognosis in systemic lupus erythematosus. A renal macrophage/dendritic cell signature is associated with the onset of nephritis in NZB/W mice, and immune-modulating therapies can reverse this signature and the associated renal damage despite ongoing immune complex deposition. In nephritic NZB/W mice, renal F4/80(hi)/CD11c(int) macrophages are located throughout the interstitium, whereas F4/80(lo)/CD11c(hi) dendritic cells accumulate in perivascular lymphoid aggregates. We show here that F4/80(hi)/CD11c(int) renal macrophages have a Gr1(lo)/Ly6C(lo)/VLA4(lo)/MHCII(hi)/CD43(lo)/CD62L(lo) phenotype different from that described for inflammatory macrophages. At nephritis onset, F4/80(hi)/CD11c(int) cells upregulate cell surface CD11b, acquire cathepsin and matrix metalloproteinase activity, and accumulate large numbers of autophagocytic vacuoles; these changes reverse after the induction of remission. Latex bead labeling of peripheral blood Gr1(lo) monocytes indicates that these are the source of F4/80(hi)/CD11c(int) macrophages. CD11c(hi)/MHCII(lo) dendritic cells are found in the kidneys only after proteinuria onset, turnover rapidly, and disappear rapidly after remission induction. Gene expression profiling of the F4/80(hi)/CD11c(int) population displays increased expression of proinflammatory, regulatory, and tissue repair/degradation-associated genes at nephritis onset that reverses with remission induction. Our findings suggest that mononuclear phagocytes with an aberrant activation profile contribute to tissue damage in lupus nephritis by mediating both local inflammation and excessive tissue remodeling.
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Affiliation(s)
- Ramalingam Bethunaickan
- Center for Autoimmunity and Musculoskeletal Diseases, Feinstein Institute for Medical Research, Manhasset, NY 11030, USA
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139
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Fairbairn L, Kapetanovic R, Sester DP, Hume DA. The mononuclear phagocyte system of the pig as a model for understanding human innate immunity and disease. J Leukoc Biol 2011; 89:855-71. [PMID: 21233410 DOI: 10.1189/jlb.1110607] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The biology of cells of the mononuclear phagocyte system has been studied extensively in the mouse. Studies of the pig as an experimental model have commonly been consigned to specialist animal science journals. In this review, we consider some of the many ways in which the innate immune systems of humans differ from those of mice, the ways that pigs may address the shortcomings of mice as models for the study of macrophage differentiation and activation in vitro, and the biology of sepsis and other pathologies in the living animal. With the completion of the genome sequence and the characterization of many key regulators and markers, the pig has emerged as a tractable model of human innate immunity and disease that should address the limited, predictive value of rodents in preclinical studies.
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Affiliation(s)
- Lynsey Fairbairn
- The Roslin Institute and Royal (Dick) School of Veterinary Medicine, University of Edinburgh, Roslin BioCentre, Scotland, United Kingdom
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140
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Kou PM, Babensee JE. Macrophage and dendritic cell phenotypic diversity in the context of biomaterials. J Biomed Mater Res A 2010; 96:239-60. [PMID: 21105173 DOI: 10.1002/jbm.a.32971] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 09/08/2010] [Accepted: 09/14/2010] [Indexed: 12/21/2022]
Abstract
Macrophages (Mϕ) and dendritic cells (DCs) are critical antigen presenting cells that play pivotal roles in host responses to biomaterial implants. Although Mϕs have been widely studied for their roles in the inflammatory responses against biomaterials, the roles that DCs play in the host responses toward implanted materials have only recently been explored. DCs are of significant research interest because of the emergence of a large number of combination products that cross-traditional medical device boundaries. These products combine biomaterials with biologics, including cells, nucleic acids, and/or proteins. The biomaterial component may evoke an inflammatory response, primarily mediated by neutrophils and Mϕs, whereas the biologic component may elicit an immunogenic immune response, initiated by DCs involving lymphocyte activation. Control of Mϕ phenotypic balance from proinflammatory M1 to reparative M2 is a goal of investigators to optimize the host response to biomaterials. Similarly, control of DC phenotype from proinflammatory to toleragenic is of interest in vaccine delivery and tissue engineering/transplantation situations, respectively. This review discusses the interconnection between innate and adaptive immunity, the comparative and contrasting phenotypes and roles of Mϕs and DCs in immunity, their responses to biomaterials and the strategies to modulate their phenotype for applications in tissue engineering and vaccine delivery. Furthermore, the collaboration between and unique roles of DCs and Mϕs needs to be addressed in future studies to gain a more complete picture of host responses toward combination products.
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Affiliation(s)
- Peng Meng Kou
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
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141
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Ng SC, Kamm MA, Stagg AJ, Knight SC. Intestinal dendritic cells: their role in bacterial recognition, lymphocyte homing, and intestinal inflammation. Inflamm Bowel Dis 2010; 16:1787-807. [PMID: 20222140 DOI: 10.1002/ibd.21247] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dendritic cells (DCs) play a key role in discriminating between commensal microorganisms and potentially harmful pathogens and in maintaining the balance between tolerance and active immunity. The regulatory role of DC is of particular importance in the gut where the immune system lies in intimate contact with the highly antigenic external environment. Intestinal DC constantly survey the luminal microenvironment. They act as sentinels, acquiring antigens in peripheral tissues before migrating to secondary lymphoid organs to activate naive T cells. They are also sensors, responding to a spectrum of environmental cues by extensive differentiation or maturation. Recent studies have begun to elucidate mechanisms for functional specializations of DC in the intestine that may include the involvement of retinoic acid and transforming growth factor-β. Specialized CD103(+) intestinal DC can promote the differentiation of Foxp3(+) regulatory T cells via a retinoic acid-dependent process. Different DC outcomes are, in part, influenced by their exposure to microbial stimuli. Evidence is also emerging of the close interaction between bacteria, epithelial cells, and DC in the maintenance of intestinal immune homeostasis. Here we review recent advances of functionally specialized intestinal DC and their mechanisms of antigen uptake and recognition. We also discuss the interaction of DC with intestinal microbiota and their ability to orchestrate protective immunity and immune tolerance in the host. Lastly, we describe how DC functions are altered in intestinal inflammation and their emerging potential as a therapeutic target in inflammatory bowel disease.
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Affiliation(s)
- S C Ng
- Antigen Presentation Research Group, Faculty of Medicine, Imperial College London, Northwick Park and St Mark's Campus, Harrow, UK
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142
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Monocyte and macrophage heterogeneity and Toll-like receptors in the lung. Cell Tissue Res 2010; 343:97-106. [DOI: 10.1007/s00441-010-1032-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 08/02/2010] [Indexed: 12/11/2022]
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143
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Strey CW, Siegmund B, Rosenblum S, Marquez-Pinilla RM, Oppermann E, Huber-Lang M, Lambris JD, Bechstein WO. Complement and neutrophil function changes after liver resection in humans. World J Surg 2010; 33:2635-43. [PMID: 19789912 DOI: 10.1007/s00268-009-0209-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Complement activation contributes to the regulation of liver regeneration after liver resection (LR) in mice. METHODS We hypothesized that complement activation and changes in C5a-receptors (C5aR, C5L2) on polymorphonuclear cells (PMN) and monocytes are important in clinical LR. Anaphylatoxin and C5b9 plasma levels were measured (bead-array, ELISA) (25 patients) and receptor expression was assessed after LR (19 patients) (FACS). In vitro PMN C5a-dependent chemotactic response (7 patients) as well as L-selectin shedding and Mac-1 expression (3 patients) was determined. RESULTS C3a increased after LR (31.1 +/- 4 before LR vs. 41.6 +/- 5 ng/ml, 30 min after LR, P < 0.01), as did C5b9 (12.7 +/- 1 before LR vs. 26.9 +/- 3 ng/ml, 60 min after LR, P < 0.001). C4a and C5a decreased after LR, by 25% 24 h after LR and 30% 2 h after LR, respectively (P < 0.01). C5L2 expression decreased at 4 h, rising at 24 h after LR (PMN: 6.3 +/- 1 before LR, 3.1 +/- 1, 4 h, 8.3 +/- 2, 24 h; P < 0.01). The receptor-related changes accompanied a diminished C5a-dependent chemotactic response by PMN (42.1 +/- 17 before LR vs. 2.1 +/- 3 4 h after LR; P < 0.01) and a reduction of activation upon C5a-R stimulation as measured by L-selectin shedding and Mac-1 expression on PMN. Changes in C5L2 expression on monocytes paralleled postoperative impairment of liver function. CONCLUSIONS These results indicate that complement components are released after clinical LR and subsequently PMN display altered C5a-dependent functional responses.
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Affiliation(s)
- Christoph Werner Strey
- Department of General and Vascular Surgery, Medical School, Johann Wolfgang Goethe-University Frankfurt, Theodor-Stern-Kai 7, Frankfurt am Main 60590, Germany.
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Karlstetter M, Walczak Y, Weigelt K, Ebert S, Van den Brulle J, Schwer H, Fuchshofer R, Langmann T. The novel activated microglia/macrophage WAP domain protein, AMWAP, acts as a counter-regulator of proinflammatory response. THE JOURNAL OF IMMUNOLOGY 2010; 185:3379-90. [PMID: 20709948 DOI: 10.4049/jimmunol.0903300] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Microgliosis is a common phenomenon in neurodegenerative disorders, including retinal dystrophies. To identify candidate genes involved in microglial activation, we used DNA-microarray analysis of retinal microglia from wild-type and retinoschisin-deficient (Rs1h(-/Y)) mice, a prototypic model for inherited retinal degeneration. Thereby, we cloned a novel 76 aa protein encoding a microglia/macrophage-restricted whey acidic protein (WAP) termed activated microglia/macrophage WAP domain protein (AMWAP). The gene consists of three exons and is located on mouse chromosome 11 in proximity to a chemokine gene cluster. mRNA expression of AMWAP was detected in microglia from Rs1h(-/Y) retinas, brain microglia, and other tissue macrophages. AMWAP transcription was rapidly induced in BV-2 microglia upon stimulation with multiple TLR ligands and IFN-gamma. The TLR-dependent expression of AMWAP was dependent on NF-kappaB, whereas its microglia/macrophage-specific transcription was regulated by PU.1. Functional characterization showed that AMWAP overexpression reduced the proinflammatory cytokines IL-6 and IL-1beta and concomitantly increased expression of the alternative activation markers arginase 1 and Cd206. Conversely, small interfering RNA knockdown of AMWAP lead to higher IL-6, IL-1beta, and Ccl2 transcript levels, whereas diminishing arginase 1 and Cd206 expression. Moreover, AMWAP expressing cells had less migratory capacity and showed increased adhesion in a trypsin-protection assay indicating antiserine protease activity. In agreement with findings from other WAP proteins, micromolar concentrations of recombinant AMWAP exhibited significant growth inhibitory activity against Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis. Taken together, we propose that AMWAP is a counter-regulator of proinflammatory microglia/macrophage activation and a potential modulator of innate immunity in neurodegeneration.
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Affiliation(s)
- Marcus Karlstetter
- Institute of Human Genetics, University of Regensburg, Regensburg, The Netherlands
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An antibody against the colony-stimulating factor 1 receptor depletes the resident subset of monocytes and tissue- and tumor-associated macrophages but does not inhibit inflammation. Blood 2010; 116:3955-63. [PMID: 20682855 DOI: 10.1182/blood-2010-02-266296] [Citation(s) in RCA: 353] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The development of the mononuclear phagocyte system requires macrophage colony-stimulating factor (CSF-1) signaling through the CSF-1 receptor (CSF1R, CD115). We examined the effect of an antibody against CSF1R on macrophage homeostasis and function using the MacGreen transgenic mouse (csf1r-enhanced green fluorescent protein) as a reporter. The administration of a novel CSF1R blocking antibody selectively reduced the CD115(+)Gr-1(neg) monocyte precursor of resident tissue macrophages. CD115(+)Gr-1(+) inflammatory monocytes were correspondingly increased, supporting the view that monocytes are a developmental series. Within tissue, the antibody almost completely depleted resident macrophage populations in the peritoneum, gastrointestinal tract, liver, kidney, and skin, but not in the lung or female reproductive organs. CSF1R blockade reduced the numbers of tumor-associated macrophages in syngeneic tumor models, suggesting that these cells are resident type macrophages. Conversely, it had no effect on inflammatory monocyte recruitment in models, including lipopolysaccharide-induced lung inflammation, wound healing, peritonitis, and severe acute graft-versus-host disease. Depletion of resident tissue macrophages from bone marrow transplantation recipients actually resulted in accelerated pathology and exaggerated donor T-cell activation. The data indicate that CSF1R signaling is required only for the maturation and replacement of resident-type monocytes and tissue macrophages, and is not required for monocyte production or inflammatory function.
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146
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Glucocorticoids promote survival of anti-inflammatory macrophages via stimulation of adenosine receptor A3. Blood 2010; 116:446-55. [DOI: 10.1182/blood-2009-10-247106] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Abstract
Active resolution of inflammation is a previously unrecognized process essential for tissue homeostasis. Monocytes play a pivotal role in the generation as well as resolution of inflammation. Glucocorticoids (GCs) are widely used anti-inflammatory agents. We demonstrate that GCs exhibit antiapoptotic effects in monocytes resulting in differentiation to an anti-inflammatory phenotype. The molecular basis of this novel antiapoptotic effect is a prolonged activation of the extracellular signal regulated kinase/mitogen-activated protein kinase (ERK/MAPK) pathway resulting in inhibition of caspase activities and expression of antiapoptotic genes via activation of c-Myc. We identified up-regulation and activation of A3 adenosine receptor (A3AR) as the initial trigger of this antiapoptotic pathway. In summary, we deciphered a novel molecular pathway promoting survival of anti-inflammatory monocytes. Specific activation of A3AR or its downstream signaling pathways may thus be a novel strategy to modulate inflammation in autoimmune disorders with fewer side effects via induction of inflammatory resolution rather than immunosuppression.
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Plager DA, Kahl JC, Asmann YW, Nilson AE, Pallanch JF, Friedman O, Kita H. Gene transcription changes in asthmatic chronic rhinosinusitis with nasal polyps and comparison to those in atopic dermatitis. PLoS One 2010; 5:e11450. [PMID: 20625511 PMCID: PMC2897889 DOI: 10.1371/journal.pone.0011450] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 05/12/2010] [Indexed: 01/21/2023] Open
Abstract
Background Asthmatic chronic rhinosinusitis with nasal polyps (aCRSwNP) is a common disruptive eosinophilic disease without effective medical treatment. Therefore, we sought to identify gene expression changes, particularly those occurring early, in aCRSwNP. To highlight expression changes associated with eosinophilic epithelial inflammation, we further compared the changes in aCRSwNP with those in a second eosinophilic epithelial disease, atopic dermatitis (AD), which is also closely related to asthma. Methods/Principal Findings Genome-wide mRNA levels measured by exon array in both nasosinus inflamed mucosa and adjacent polyp from 11 aCRSwNP patients were compared to those in nasosinus tissue from 17 normal or rhinitis subjects without polyps. Differential expression of selected genes was confirmed by qRT-PCR or immunoassay, and transcription changes common to AD were identified. Comparison of aCRSwNP inflamed mucosa and polyp to normal/rhinitis tissue identified 447 differentially transcribed genes at ≥2 fold-change and adjusted p-value<0.05. These included increased transcription of chemokines localized to chromosome 17q11.2 (CCL13, CCL2, CCL8, and CCL11) that favor eosinophil and monocyte chemotaxis and chemokines (CCL18, CCL22, and CXCL13) that alternatively-activated monocyte-derived cells have been shown to produce. Additional transcription changes likely associated with Th2-like eosinophilic inflammation were prominent and included increased IL1RL1 (IL33 receptor) and EMR1&3 and decreased CRISP2&3. A down-regulated PDGFB-centric network involving several smooth muscle-associated genes was also implicated. Genes at 17q11.2, genes associated with alternative activation or smooth muscle, and the IL1RL1 gene were also differentially transcribed in AD. Conclusions/Significance Our data implicate several genes or gene sets in aCRSwNP and eosinophilic epithelial inflammation, some that likely act in the earlier stages of inflammation. The identified gene expression changes provide additional diagnostic and therapeutic targets for aCRSwNP and other eosinophilic epithelial diseases.
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Affiliation(s)
- Douglas A Plager
- Allergic Diseases Research Laboratory, Mayo Clinic, Rochester, Minnesota, United States of America.
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Abstract
When Ralph Steinman and Zanvil Cohn first described dendritic cells (DCs) in 1973 it took many years to convince the immunology community that these cells were truly distinct from macrophages. Almost four decades later, the DC is regarded as the key initiator of adaptive immune responses; however, distinguishing DCs from macrophages still leads to confusion and debate in the field. Here, Nature Reviews Immunology asks five experts to discuss the issue of heterogeneity in the mononuclear phagocyte system and to give their opinion on the importance of defining these cells for future research.
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El Chartouni C, Rehli M. Comprehensive analysis of TLR4-induced transcriptional responses in interleukin 4-primed mouse macrophages. Immunobiology 2010; 215:780-7. [PMID: 20692533 DOI: 10.1016/j.imbio.2010.05.032] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Accepted: 05/26/2010] [Indexed: 11/15/2022]
Abstract
Interferon (IFN)gamma and interleukin (IL)-4 are central regulators of T helper 1 (Th1) and T helper 2 (Th2) immune responses, respectively. Both cytokines have a major impact on macrophage phenotypes: IFNgamma-priming and subsequent TLR4 activation induces so-called "classically activated" macrophages that are characterized by pronounced pro-inflammatory responses, whereas IL-4-treated macrophages, commonly called "alternatively activated", are known to develop enhanced capacity for endocytosis, antigen presentation and tissue repair and are generally considered anti-inflammatory. Considering IL-4 as priming rather than activating stimulus, we now compared the TLR4-dependent global gene activation program in IFNgamma- versus IL-4-pretreated mouse macrophages, which has rarely been studied so far. Although both cytokines frequently induced opposing effects on gene transcription, the subsequent activation of bone marrow-derived macrophages by lipopolysaccharide (LPS) produced a strong, priming-dependent pro-inflammatory response in both macrophage types. For example, the production of key pro-inflammatory cytokines IL-6 and IL-12 was significantly higher in IL-4- versus IFNgamma-primed macrophages and several cytokine genes, including Il19, Ccl17, Ccl22, Ccl24 and Cxcl5, were preferentially induced in "alternatively" primed and LPS activated mouse macrophages. In a subset of genes, including IL12a, IFNgamma-priming was actually found to suppress LPS-induced gene expression in a Stat1-dependent manner. Our data suggest that IL-4-priming is not per se anti-inflammatory but generates a macrophage that is "tissue protective" but still capable of mounting a strong inflammatory response after TLR4-dependent activation.
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Affiliation(s)
- Carol El Chartouni
- Department of Haematology and Oncology, University Hospital Regensburg, Regensburg, Germany
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Meta-analysis of lineage-specific gene expression signatures in mouse leukocyte populations. Immunobiology 2010; 215:724-36. [PMID: 20580463 DOI: 10.1016/j.imbio.2010.05.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 05/20/2010] [Indexed: 12/15/2022]
Abstract
In order to address fundamental questions associated with the relationships between mononuclear phagocytes and other myeloid and lymphoid cell populations, we have taken advantage of the growing body of expression data available in the public domain. We collated a large number of published expression studies on mouse haemopoietic cell lineages comprising 304 cell samples from 29 independent experiments performed on a single microarray platform (Affymetrix MOE430-2). The data were subjected to network-based cluster analysis using Biolayout Express(3D). Genes with related function clustered together in distinct regions of the graph reaffirming many known associations between gene expression and role in specific pathways and defining most major cell types of the immune system. Promoters of genes within individual clusters were distinguished by over-representation of regulatory motifs recognised by specific transcription factors. However, these data indicate that commonly used myeloid subpopulation markers, such as CD11c (Itgax), do not correlate with expression of other genes, and further bring into question their use in defining myeloid cell lineage, activation (M1 vs. M2) and antigen-presenting cell function. In particular, there were few mRNA markers that clearly distinguished classical dendritic cells (DC) from macrophages, other than low expression of genes required for phagocytic activity. Bone marrow-derived DC, grown in GM-CSF, were clearly identified as phagocytes and distinguished from isolated lymphoid tissue DC. Thus, through pooling datasets from public data and examining the gene expression clusters within, we can learn a great deal about the transcriptional networks that underpin the differences in functional activities between cell populations of the immune system.
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