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Galli SJ, Gaudenzio N, Tsai M. Mast Cells in Inflammation and Disease: Recent Progress and Ongoing Concerns. Annu Rev Immunol 2021; 38:49-77. [PMID: 32340580 DOI: 10.1146/annurev-immunol-071719-094903] [Citation(s) in RCA: 168] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Mast cells have existed long before the development of adaptive immunity, although they have been given different names. Thus, in the marine urochordate Styela plicata, they have been designated as test cells. However, based on their morphological characteristics (including prominent cytoplasmic granules) and mediator content (including heparin, histamine, and neutral proteases), test cells are thought to represent members of the lineage known in vertebrates as mast cells. So this lineage presumably had important functions that preceded the development of antibodies, including IgE. Yet mast cells are best known, in humans, as key sources of mediators responsible for acute allergic reactions, notably including anaphylaxis, a severe and potentially fatal IgE-dependent immediate hypersensitivity reaction to apparently harmless antigens, including many found in foods and medicines. In this review, we briefly describe the origins of tissue mast cells and outline evidence that these cells can have beneficial as well as detrimental functions, both innately and as participants in adaptive immune responses. We also discuss aspects of mast cell heterogeneity and comment on how the plasticity of this lineage may provide insight into its roles in health and disease. Finally, we consider some currently open questions that are yet unresolved.
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Affiliation(s)
- Stephen J Galli
- Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA; , .,Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA.,Sean N. Parker Center for Allergy and Asthma Research, Stanford University School of Medicine, California 94305, USA
| | - Nicolas Gaudenzio
- Unité de Différenciation Epithéliale et Autoimmunité Rhumatoïde (UDEAR), INSERM UMR 1056, Université de Toulouse, 31 059 Toulouse CEDEX 9, France;
| | - Mindy Tsai
- Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA; , .,Sean N. Parker Center for Allergy and Asthma Research, Stanford University School of Medicine, California 94305, USA
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Karimi A, Shahrooz R, Hobbenaghi R, Mohammadi R, Mortaz E. Mouse Bone Marrow-Derived Mast Cells Induce Angiogenesis by Tissue Engineering in Rats: Histological Evidence. CELL JOURNAL 2017; 19:578-584. [PMID: 29105392 PMCID: PMC5672096 DOI: 10.22074/cellj.2018.4277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 09/14/2016] [Indexed: 12/12/2022]
Abstract
Objective Therapeutic angiogenesis is employed to induce vascular network formation and improve functional
recovery in ischemia. The aim of this study is to find an appropriate method to recover local ischemic conditions.
Materials and Methods In this experimental survey, 20 male Wistar rats weighing approximately 200-250 g were
randomly divided into four experimental groups respectively: ischemia group in which the femoral artery was transected;
phosphate buffer solution group (PBS) in which the femoral artery transected location was immersed with PBS; chitosan
(CHIT) group in which the transected location was immersed in a 50 µL CHIT solution; and mast cell transplanted group in
which the transected location was immersed with a mixture of 50 µL CHIT and 50 µL PBS that contained 1×106 mast cells.
Results On day 14 after surgery, mean numbers of blood vessels of different sizes in the CHIT/mast cell group
significantly increased compared to the other experimental groups (P<0.05).
Conclusion Our data suggest that mast cell reconstitution could offer a new approach for therapeutic angiogenesis in
cases of peripheral arterial diseases.
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Affiliation(s)
- Ali Karimi
- Department of Basic Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
| | - Rasoul Shahrooz
- Department of Basic Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
| | - Rahim Hobbenaghi
- Department of Pathobiology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
| | - Rahim Mohammadi
- Department of Surgery and Diagnostic Imaging, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
| | - Esmaeil Mortaz
- Massih Daneshvari Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, Netherlands
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Mast cells improve functional recovery of transected peripheral nerve: A novel preliminary study. Injury 2017; 48:1480-1485. [PMID: 28532897 DOI: 10.1016/j.injury.2017.05.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 04/24/2017] [Accepted: 05/09/2017] [Indexed: 02/02/2023]
Abstract
BACKGROUND Employment of regenerative properties of cells at the service of nerve repair has been initiated during recent decades. Effects of local transplantation of bone marrow-derived mast cells on peripheral nerve regeneration were studied using a rat sciatic nerve transection model. MATERIALS AND METHODS A 10-mm sciatic nerve defect was bridged using a conduit chitosan-based hybrid conduit filled with BMMCs in BMMC group. In positive control group (Pos), the conduit was filled with phosphate-buffered saline alone. The regenerated nerve fibers were studied within 12 weeks after surgery. In sham-operated group, the sciatic nerve was only exposed and manipulated. In negative control (Neg) a 10-mm sciatic nerve defect was created and the nerve stumps were sutured to the adjacent muscles. The regenerated nerve fibers were studied functionally, biomechanically, histologically and immunohiscochemically. RESULTS Functional and biomechanical studies confirmed faster recovery of regenerated axons in BMMCs transplanted animals compared to Pos group (p<0.05). Morphometric indices of the regenerated fibers showed that the number and diameter of the myelinated fibers were significantly higher in BMMCs transplanted animals than in Pos group (p<0.05). In immunohistochemistry, location of reactions to S-100 in BMMCs transplanted animals was clearly more positive than that in Pos group. CONCLUSIONS BMMCs transplantation could be considered as a readily accessible source of cells that could improve functional recovery of transected sciatic nerve.
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Ozaki K, Yamagami T, Nomura K, Narama I. Mast Cell Tumors of the Gastrointestinal Tract in 39 Dogs. Vet Pathol 2016; 39:557-64. [PMID: 12243465 DOI: 10.1354/vp.39-5-557] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mast cell tumors (MCTs) of gastrointestinal origin that had been surgically removed from 39 dogs were examined to evaluate their pathologic features. Miniature breeds, especially Maltese, were most frequently affected. The average age of affected dogs was 9.7 ± 2.6 years. No sex difference was apparent. The most frequently affected sites were in the upper digestive tract, and the prognosis was very poor. Grossly, the gastrointestinal wall was prominently thickened, and the lumen of the affected gut was usually narrowed. Microscopically, there was diffuse transmural invasion of round to pleomorphic tumor cells. Tumor cells had moderate to abundant cytoplasm, round to ovoid nuclei with scattered chromatin, and mitotic figures. Fibrous stroma was observed in about half of the tumors. There was variable infiltration of eosinophils. In all tumors, cytoplasmic granules showed weak metachromasia, but the number of granules was very small. Immunohistochemical staining for c-kit and mast cell tryptase was positive in 77% and 62% of tumors, respectively. All tumors were positive for at least two of these markers. Immunohistochemical staining for p53 was positive in 13% of the tumors. Reactivity for staining markers and p53 was unrelated to cell pleomorphism, vessel invasion, or survival time. Gastrointestinal MCTs have histologic and immunohistochemical features completely different from those of other primary or metastatic gastrointestinal tumors. The combination of immunostaining for mast cell tryptase and c-kit and histochemical staining for metachromasia appears to be a powerful tool for the diagnosis of gastrointestinal MCTs.
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Affiliation(s)
- K Ozaki
- Research Institute of Drug Safety, Setsunan University, Hirakata, Osaka, Japan.
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Reber LL, Sibilano R, Mukai K, Galli SJ. Potential effector and immunoregulatory functions of mast cells in mucosal immunity. Mucosal Immunol 2015; 8:444-63. [PMID: 25669149 PMCID: PMC4739802 DOI: 10.1038/mi.2014.131] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 11/27/2014] [Indexed: 02/04/2023]
Abstract
Mast cells (MCs) are cells of hematopoietic origin that normally reside in mucosal tissues, often near epithelial cells, glands, smooth muscle cells, and nerves. Best known for their contributions to pathology during IgE-associated disorders such as food allergy, asthma, and anaphylaxis, MCs are also thought to mediate IgE-associated effector functions during certain parasite infections. However, various MC populations also can be activated to express functional programs--such as secreting preformed and/or newly synthesized biologically active products--in response to encounters with products derived from diverse pathogens, other host cells (including leukocytes and structural cells), damaged tissue, or the activation of the complement or coagulation systems, as well as by signals derived from the external environment (including animal toxins, plant products, and physical agents). In this review, we will discuss evidence suggesting that MCs can perform diverse effector and immunoregulatory roles that contribute to homeostasis or pathology in mucosal tissues.
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Affiliation(s)
- Laurent L Reber
- Department of Pathology, Stanford University, School of Medicine, Stanford, California 94305-5324, USA
| | - Riccardo Sibilano
- Department of Pathology, Stanford University, School of Medicine, Stanford, California 94305-5324, USA
| | - Kaori Mukai
- Department of Pathology, Stanford University, School of Medicine, Stanford, California 94305-5324, USA
| | - Stephen J Galli
- Department of Pathology, Stanford University, School of Medicine, Stanford, California 94305-5324, USA,Department of Microbiology & Immunology, Stanford University, School of Medicine, Stanford, California 94305-5324, USA
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Galli SJ, Tsai M, Marichal T, Tchougounova E, Reber LL, Pejler G. Approaches for analyzing the roles of mast cells and their proteases in vivo. Adv Immunol 2015; 126:45-127. [PMID: 25727288 DOI: 10.1016/bs.ai.2014.11.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The roles of mast cells in health and disease remain incompletely understood. While the evidence that mast cells are critical effector cells in IgE-dependent anaphylaxis and other acute IgE-mediated allergic reactions seems unassailable, studies employing various mice deficient in mast cells or mast cell-associated proteases have yielded divergent conclusions about the roles of mast cells or their proteases in certain other immunological responses. Such "controversial" results call into question the relative utility of various older versus newer approaches to ascertain the roles of mast cells and mast cell proteases in vivo. This review discusses how both older and more recent mouse models have been used to investigate the functions of mast cells and their proteases in health and disease. We particularly focus on settings in which divergent conclusions about the importance of mast cells and their proteases have been supported by studies that employed different models of mast cell or mast cell protease deficiency. We think that two major conclusions can be drawn from such findings: (1) no matter which models of mast cell or mast cell protease deficiency one employs, the conclusions drawn from the experiments always should take into account the potential limitations of the models (particularly abnormalities affecting cell types other than mast cells) and (2) even when analyzing a biological response using a single model of mast cell or mast cell protease deficiency, details of experimental design are critical in efforts to define those conditions under which important contributions of mast cells or their proteases can be identified.
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Affiliation(s)
- Stephen J Galli
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA; Microbiology & Immunology, Stanford University School of Medicine, Stanford, California, USA.
| | - Mindy Tsai
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | - Thomas Marichal
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA; GIGA-Research and Faculty of Veterinary Medicine, University of Liege, Liege, Belgium
| | - Elena Tchougounova
- Department of Immunology, Genetics, and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Laurent L Reber
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | - Gunnar Pejler
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden; Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden
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Saito H. Progress in allergy signal research on mast cells: systemic approach to mast cell biology in allergic diseases. J Pharmacol Sci 2008; 106:341-6. [PMID: 18360090 DOI: 10.1254/jphs.fm0070192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
At the end of the last century, microarray technology that examines the total genes and transcripts present in a cell became available as a laboratory tool. Mast cells are known to play a pivotal role in initiating allergic inflammation by releasing various mediators and cytokines. According to the recent microarray-based studies, mast cells have been found to be much more versatile functional molecules than we ever thought. Also, genes that are exclusively expressed in mast cells have been identified in comparison with other cell types. In this article, the outcome of microarray-based analyses on the role of mast cells in allergic inflammation will be reviewed by focusing on the mast cell-specific genes as drug targets.
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Affiliation(s)
- Hirohisa Saito
- Department of Allergy and Immunology, National Research Institute for Child Health & Development, Japan.
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Kitamura Y, Oboki K, Ito A. Development of mast cells. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2007; 83:164-74. [PMID: 24367142 PMCID: PMC3855204 DOI: 10.2183/pjab.83.164] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Accepted: 06/12/2007] [Indexed: 05/12/2023]
Abstract
Mast cells are progeny of the multipotential hematopoietic stem cell (MHSC). Mast cell-committed progenitors (MCPs) leave hematopoietic tissues, migrate in peripheral blood, invade to connective or mucosal tissue, proliferate and differentiate to morphologically identifiable mast cells. Phenotype of mast cells (connective tissue-type or mucosal type) is determined by the site of lodgment of MCPs. Most progeny of the multipotential hematopoietic stem cell lose proliferation potential after maturation, but connective tissue-type mast cells (CTMCs) possess appreciable proliferation potential after maturation. Even after functioning by degranulation, CTMCs proliferate and restore the original morphology. The most important cytokine for development and survival of mast cells is KIT ligand, and the KIT receptor tyrosine kinase is expressed through the whole developmental process of mast cells from MHSC to mature mast cells. The loss-of-function mutation of KIT gene results in depletion of mast cells, whereas its gain-of-function mutation causes mast cell tumors. Since mast cells are involved in various disease processes, intervention in development of mast cells might be beneficial to the treatment.
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Affiliation(s)
- Yukihiko Kitamura
- Developmental Research Laboratories, Shionogi Co., Ltd., Futaba-cho 3–1–1, Toyonaka, Osaka 561–0825,
Japan
- Recipient of Japan Academy Prize in 2005
- Correspondence to : Y. Kitamura ()
| | - Keisuke Oboki
- Department of Allergy and Immunology, National Research Institute for Child Health and Development, Okura 2–10–1, Setagaya, Tokyo 157–8535,
Japan
| | - Akihiko Ito
- Division of Pathology, Graduate School of Medicine, Kobe University, Kusunoki-cho 7–5–1, Kobe, Hyogo 650–0017,
Japan
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Abstract
Mast cells are progeny of multipotential hematopoietic stem cells (MHSCs). MHSCs commit to the mast cell lineage in the bone marrow, and the mast cell-committed progenitors leave the bone marrow, migrate in blood, invade connective or mucosal tissue, and then proliferate and differentiate to connective tissue-type or mucosal mast cell. GATA-1, GATA-2, and PU.1 transcription factors seem to be involved i the commitment to mast cells, and MITF, a basic helix-loop-helix leucine zipper-type transcription factor, seems to be involved in the migration, phenotypic expression, and survival of mast cells. KIT ligand (KITL) is the most important cytoline for development of mast cells, and KIT is the receptor of KITL. Tissues of loss-of-function mutants of KIT, KITL, or MITF are deficient in mast cells.
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Affiliation(s)
- Yukihiko Kitamura
- Developmental Research Laboratories, Shionogi and Company, 3-1-1 Futaba-cho, Toyonaka, Osaka, 561-0825, Japan.
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Velin D, Bachmann D, Bouzourene H, Michetti P. Mast cells are critical mediators of vaccine-induced Helicobacter clearance in the mouse model. Gastroenterology 2005; 129:142-55. [PMID: 16012944 DOI: 10.1053/j.gastro.2005.04.010] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Despite the proven ability of immunization to prevent Helicobacter infection in mouse models, the precise mechanism of protection has remained elusive. METHODS We explored the cellular events associated with Helicobacter clearance from the stomach following vaccination by flow cytometry analysis and histological and molecular studies. RESULTS Kinetic studies showed that the infection is undetectable in vaccinated mice at day 5 postbacterial challenge. Flow cytometry analysis showed that the percentages of mast cells (CD3 - CD117 + ) increased in the lymphoid cells isolated from the stomach at day 4 postchallenge in urease + cholera toxin (CT)-vaccinated mice in comparison with mice administered with CT alone (9.4% +/- 4.4% and 3.1% +/- 1%, respectively, for vaccinated and CT administered, n = 5; P < .01). Quantitative PCR analysis showed an increased messenger RNA (mRNA) expression of the mast cell proteases 1 and 2 at day 5 postchallenge in the stomach of vaccinated mice. In contrast to wild-type mice, mast cell-deficient mice (W/W v mice) were not protected from H felis colonization after vaccination. Indeed only 1 out of 12 vaccinated W/W v mice showed a negative urease test. Remarkably, vaccinated W/W v mice reconstituted with cultured bone marrow-derived mast cells recovered the ability to clear the infection after vaccination (8 out of 10 mast cell-reconstituted mice showed negative urease tests [ P < .006 as compared with wild-type mice]). CONCLUSIONS These experiments show that mast cells are, unexpectedly, critical mediators of anti- Helicobacter vaccination.
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Affiliation(s)
- Dominique Velin
- Service de Gastro-entérologie et d'Hépatologie, CHUV, Lausanne, Switzerland.
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Galli SJ, Kalesnikoff J, Grimbaldeston MA, Piliponsky AM, Williams CMM, Tsai M. Mast cells as "tunable" effector and immunoregulatory cells: recent advances. Annu Rev Immunol 2005; 23:749-86. [PMID: 15771585 DOI: 10.1146/annurev.immunol.21.120601.141025] [Citation(s) in RCA: 931] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review focuses on recent progress in our understanding of how mast cells can contribute to the initiation, development, expression, and regulation of acquired immune responses, both those associated with IgE and those that are apparently expressed independently of this class of Ig. We emphasize findings derived from in vivo studies in mice, particularly those employing genetic approaches to influence mast cell numbers and/or to alter or delete components of pathways that can regulate mast cell development, signaling, or function. We advance the hypothesis that mast cells not only can function as proinflammatory effector cells and drivers of tissue remodeling in established acquired immune responses, but also may contribute to the initiation and regulation of such responses. That is, we propose that mast cells can also function as immunoregulatory cells. Finally, we show that the notion that mast cells have primarily two functional configurations, off (or resting) or on (or activated for extensive mediator release), markedly oversimplifies reality. Instead, we propose that mast cells are "tunable," by both genetic and environmental factors, such that, depending on the circumstances, the cell can be positioned phenotypically to express a wide spectrum of variation in the types, kinetics, and/or magnitude of its secretory functions.
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Affiliation(s)
- Stephen J Galli
- Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA.
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Kashiwakura JI, Yokoi H, Saito H, Okayama Y. T cell proliferation by direct cross-talk between OX40 ligand on human mast cells and OX40 on human T cells: comparison of gene expression profiles between human tonsillar and lung-cultured mast cells. THE JOURNAL OF IMMUNOLOGY 2004; 173:5247-57. [PMID: 15470070 DOI: 10.4049/jimmunol.173.8.5247] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mast cells (MCs) are the primary effector cells in allergic reactions and have also been found to activate T cells and to reside in close physical proximity to T cells. However, the molecular mechanisms involved in the MC-T cell interaction remain unclear. We hypothesized that human tonsillar MCs, which locate in the interfollicular areas, might interact with T cells. Thus, we first established a culture system of human tonsillar MCs and then compared gene expression profiles of tonsillar MCs with that of lung MCs before and after aggregation of FcepsilonRI by using high-density oligonucleotide probe arrays. Here we show that resting tonsillar MCs, when compared with lung MCs, revealed significantly higher expression levels for CC chemokines (CCL3 and 4), which recruit T cells, and for TNFR superfamilies (OX40 ligand and 4-1BB ligand), which induce proliferation of T cells. After aggregation of FcepsilonRI, not only tonsillar MCs but also lung MCs up-regulated the expression of these molecules. We confirmed that T cell proliferation is induced in direct cross-talk by the MC surface molecule OX40 ligand. These results suggest that human MCs may play important roles in adaptive immunity through the T cell responses.
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Affiliation(s)
- Jun-ichi Kashiwakura
- Research Unit for Allergy Transcriptome, Research Center for Allergy and Immunology, The Institute of Physical and Chemical Research, (RIKEN) Yokohama Institute, Suehiro-cho, Tsurumi-ku, Japan
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Khalil MH, Silverman AJ, Silver R. Mast cells in the rat brain synthesize gonadotropin-releasing hormone. JOURNAL OF NEUROBIOLOGY 2003; 56:113-24. [PMID: 12838577 PMCID: PMC3275351 DOI: 10.1002/neu.10220] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Mast cells occur in the brain and their number changes with reproductive status. While it has been suggested that brain mast cells contain the mammalian hypothalamic form of gonadotropin-releasing hormone (GnRH-I), it is not known whether mast cells synthesize GnRH-I de novo. In the present study, mast cells in the rat thalamus were immunoreactive to antisera generated against GnRH-I and the GnRH-I associated peptide (GAP); mast cell identity was confirmed by the presence of heparin, a molecule specific to mast cells, or serotonin. To test whether mast cells synthesize GnRH-I mRNA, in situ hybridization was performed using a GnRH-I cRNA probe, and the signal was identified as being within mast cells by the binding of avidin to heparin. GnRH-I mRNA was also found, using RT-PCR, in mast cells isolated from the peritoneal cavity. Given the function of GnRH-I in the regulation of reproduction, changes in the population of brain GnRH-I mast cells were investigated. While housing males with sexually receptive females for 2 h or 5 days resulted in a significant increase in the number of brain mast cells, the proportion of mast cells positive for GnRH-I was similar to that in males housed with a familiar male. These findings represent the first report showing that mast cells synthesize GnRH-I and that the mast cell increase seen in a reproductive context is the result of a parallel increase in GnRH-I positive and non-GnRH-I positive mast cells.
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Affiliation(s)
- Mona H Khalil
- Department of Biochemistry and Molecular Biophysics, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA
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Abstract
Angiogenesis is tightly regulated by pro- and anti-angiogenic factors. Secreting mast cells are able to induce and enhance angiogenesis via multiple in part interacting pathways. They include mast cell-derived (i) potent pro-angiogenic factors such as VEGF, bFGF, TGF-beta, TNF-alpha and IL-8, (ii) proteinases and heparin, that release heparin-binding pro-angiogenic factors lodged on cell surfaces and in the extracellular matrix (ECM), (iii) histamine, VEGF, and certain lipid-derived mediators that induce microvascular hyperpermeability having pro-angiogenic effects, (iv) chemotactic recruitment of monocytes/macrophages and lymphocytes that are able to contribute with angiogenesis-modulating molecules, (v) activation of platelets that release pro-angiogenic factors, (vi) activation of neighboring stationary non-mast cells, which secrete pro-angiogenic factors, ECM-degrading proteinases and stem cell factor which attracts, mitogenically stimulates and activates mast cells, (vii) auto- and paracrine stimulation of mast cells by stem cell factor, (viii) recruitment of mast cells by pro-angiogenic factors such as VEGF, bFGF and TGF-beta. As a result of ECM-degradation and changes in the microenvironment following initial mast cell secretion, the mast cell populations may change significantly in number, phenotype and function. In tumor models, mast cells have been shown to play a decisive role in inducing the angiogenic switch which precedes malignant transformation. There is, moreover, strong evidence that mast cells significantly influence angiogenesis and thus growth and progression in human cancers.
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Affiliation(s)
- Klas Norrby
- Department of Pathology, Sahlgrenska University Hospital, Göteborg, Sweden
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