1
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Liu A, Garrett S, Hong W, Zhang J. Staphylococcus aureus Infections and Human Intestinal Microbiota. Pathogens 2024; 13:276. [PMID: 38668232 PMCID: PMC11053856 DOI: 10.3390/pathogens13040276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 03/18/2024] [Accepted: 03/23/2024] [Indexed: 04/29/2024] Open
Abstract
Staphylococcus aureus (S. aureus) is a common pathogen that can cause many human diseases, such as skin infection, food poisoning, endocarditis, and sepsis. These diseases can be minor infections or life-threatening, requiring complex medical management resulting in substantial healthcare costs. Meanwhile, as the critically ignored "organ," the intestinal microbiome greatly impacts physiological health, not only in gastrointestinal diseases but also in disorders beyond the gut. However, the correlation between S. aureus infection and intestinal microbial homeostasis is largely unknown. Here, we summarized the recent progress in understanding S. aureus infections and their interactions with the microbiome in the intestine. These summarizations will help us understand the mechanisms behind these infections and crosstalk and the challenges we are facing now, which could contribute to preventing S. aureus infections, effective treatment investigation, and vaccine development.
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Affiliation(s)
- Aotong Liu
- Department of Pharmacology & Regenerative Medicine, College of Medicine, University of Illinois Chicago, Chicago, IL 60612, USA;
| | - Shari Garrett
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois Chicago, Chicago, IL 60612, USA;
- Department of Microbiology and Immunology, University of Illinois Chicago, Chicago, IL 60612, USA
| | - Wanqing Hong
- Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
- School of Chemistry & Chemical Engineering and Materials Sciences, Shandong Normal University, Jinan 250061, China
| | - Jilei Zhang
- Department of Pharmacology & Regenerative Medicine, College of Medicine, University of Illinois Chicago, Chicago, IL 60612, USA;
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2
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Nanda N, Alphonse MP. From Host Defense to Metabolic Signatures: Unveiling the Role of γδ T Cells in Bacterial Infections. Biomolecules 2024; 14:225. [PMID: 38397462 PMCID: PMC10886488 DOI: 10.3390/biom14020225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/12/2024] [Accepted: 02/12/2024] [Indexed: 02/25/2024] Open
Abstract
The growth of antibiotic-resistant bacterial infections necessitates focusing on host-derived immunotherapies. γδ T cells are an unconventional T cell subset, making up a relatively small portion of healthy circulating lymphocytes but a substantially increased proportion in mucosal and epithelial tissues. γδ T cells are activated and expanded in response to bacterial infection, having the capability to produce proinflammatory cytokines to recruit neutrophils and clear infection. They also play a significant role in dampening immune response to control inflammation and protecting the host against secondary challenge, making them promising targets when developing immunotherapy. Importantly, γδ T cells have differential metabolic states influencing their cytokine profile and subsequent inflammatory capacity. Though these differential metabolic states have not been well studied or reviewed in the context of bacterial infection, they are critical in understanding the mechanistic underpinnings of the host's innate immune response. Therefore, this review will focus on the context-specific host defense conferred by γδ T cells during infection with Staphylococcus aureus, Streptococcus pneumoniae, Listeria monocytogenes, and Mycobacterium tuberculosis.
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Affiliation(s)
| | - Martin P. Alphonse
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
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3
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Huang J, Xu Y. Autoimmunity: A New Focus on Nasal Polyps. Int J Mol Sci 2023; 24:ijms24098444. [PMID: 37176151 PMCID: PMC10179643 DOI: 10.3390/ijms24098444] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/28/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023] Open
Abstract
Chronic rhinosinusitis with nasal polyps (CRSwNP) has long been considered a benign, chronic inflammatory, and hyperplastic disease. Recent studies have shown that autoimmune-related mechanisms are involved in the pathology of nasal polyps. Activated plasma cells, eosinophils, basophils, innate type 2 lymphocytes, mast cells, and proinflammatory cytokine in polyp tissue indicate the mobilization of innate and adaptive immune pathways during polyp formation. The discovery of a series of autoantibodies further supports the autoimmune nature of nasal polyps. Local homeostasis dysregulation, infection, and chronic inflammation may trigger autoimmunity through several mechanisms, including autoantigens overproduction, microbial translocation, molecular mimicry, superantigens, activation or inhibition of receptors, bystander activation, dysregulation of Toll-Like Receptors (TLRs), epitope spreading, autoantigens complementarity. In this paper, we elaborated on the microbiome-mediated mechanism, abnormal host immunity, and genetic changes to update the role of autoimmunity in the pathogenesis of chronic rhinosinusitis with nasal polyps.
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Affiliation(s)
- Jingyu Huang
- Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
| | - Yu Xu
- Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
- Research Institute of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan 430060, China
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4
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Mata Forsberg M, Arasa C, van Zwol W, Uzunçayir S, Schönbichler A, Regenthal P, Schelin J, Lindkvist-Petersson K, Björkander S, Sverremark-Ekström E. Activation of human γδ T cells and NK cells by Staphylococcal enterotoxins requires both monocytes and conventional T cells. J Leukoc Biol 2021; 111:597-609. [PMID: 34114693 DOI: 10.1002/jlb.3a1020-630rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Staphylococcal enterotoxins (SE) pose a great threat to human health due to their ability to bypass antigen presentation and activate large amounts of conventional T cells resulting in a cytokine storm potentially leading to toxic shock syndrome. Unconventional T- and NK cells are also activated by SE but the mechanisms remain poorly understood. In this study, the authors aimed to explore the underlying mechanism behind SE-mediated activation of MAIT-, γδ T-, and NK cells in vitro. CBMC or PBMC were stimulated with the toxins SEA, SEH, and TSST-1, and cytokine and cytotoxic responses were analyzed with ELISA and flow cytometry. All toxins induced a broad range of cytokines, perforin and granzyme B, although SEH was not as potent as SEA and TSST-1. SE-induced IFN-γ expression in MAIT-, γδ T-, and NK cells was clearly reduced by neutralization of IL-12, while cytotoxic compounds were not affected at all. Kinetic assays showed that unconventional T cell and NK cell-responses are secondary to the response in conventional T cells. Furthermore, co-cultures of isolated cell populations revealed that the ability of SEA to activate γδ T- and NK cells was fully dependent on the presence of both monocytes and αβ T cells. Lastly, it was found that SE provoked a reduced and delayed cytokine response in infants, particularly within the unconventional T and NK cell populations. This study provides novel insights regarding the activation of unconventional T- and NK cells by SE, which contribute to understanding the vulnerability of young children towards Staphylococcus aureus infections.
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Affiliation(s)
- Manuel Mata Forsberg
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Claudia Arasa
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Willemien van Zwol
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Sibel Uzunçayir
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Anna Schönbichler
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Paulina Regenthal
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Jenny Schelin
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | | | - Sophia Björkander
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Eva Sverremark-Ekström
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
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5
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Shepherd FR, McLaren JE. T Cell Immunity to Bacterial Pathogens: Mechanisms of Immune Control and Bacterial Evasion. Int J Mol Sci 2020; 21:E6144. [PMID: 32858901 PMCID: PMC7504484 DOI: 10.3390/ijms21176144] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 02/06/2023] Open
Abstract
The human body frequently encounters harmful bacterial pathogens and employs immune defense mechanisms designed to counteract such pathogenic assault. In the adaptive immune system, major histocompatibility complex (MHC)-restricted αβ T cells, along with unconventional αβ or γδ T cells, respond to bacterial antigens to orchestrate persisting protective immune responses and generate immunological memory. Research in the past ten years accelerated our knowledge of how T cells recognize bacterial antigens and how many bacterial species have evolved mechanisms to evade host antimicrobial immune responses. Such escape mechanisms act to corrupt the crosstalk between innate and adaptive immunity, potentially tipping the balance of host immune responses toward pathological rather than protective. This review examines the latest developments in our knowledge of how T cell immunity responds to bacterial pathogens and evaluates some of the mechanisms that pathogenic bacteria use to evade such T cell immunosurveillance, to promote virulence and survival in the host.
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Affiliation(s)
| | - James E. McLaren
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, UK;
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6
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Cooper AJR, Lalor SJ, McLoughlin RM. Activation of Human Vδ2 + γδ T Cells by Staphylococcus aureus Promotes Enhanced Anti-Staphylococcal Adaptive Immunity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 205:1039-1049. [PMID: 32651220 PMCID: PMC7416323 DOI: 10.4049/jimmunol.2000143] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 06/15/2020] [Indexed: 12/14/2022]
Abstract
Murine studies have shown the potential for γδ T cells to mediate immunity to Staphylococcus aureus in multiple tissue settings by the secretion of diverse cytokines. However, the role played by γδ T cells in human immune responses to S. aureus is almost entirely unknown. In this study, we establish the capacity of human Vδ2+ γδ T cells for rapid activation in response to S. aureus In coculture with S. aureus-infected monocyte-derived dendritic cells (DCs), Vδ2+ cells derived from peripheral blood rapidly upregulate CD69 and secrete high levels of IFN-γ. DCs mediate this response through direct contact and IL-12 secretion. In turn, IFN-γ released by Vδ2+ cells upregulates IL-12 secretion by DCs in a positive feedback loop. Furthermore, coculture with γδ T cells results in heightened expression of the costimulatory molecule CD86 and the lymph node homing molecule CCR7 on S. aureus-infected DCs. In cocultures of CD4+ T cells with S. aureus-infected DCs, the addition of γδ T cells results in heightened CD4+ T cell activation. Our findings identify γδ T cells as potential key players in the early host response to S. aureus during bloodstream infection, promoting enhanced responses by both innate and adaptive immune cell populations, and support their consideration in the development of host-directed anti-S. aureus treatments.
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Affiliation(s)
- Andrew J R Cooper
- Host Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Dublin 2, Ireland
| | - Stephen J Lalor
- Host Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Dublin 2, Ireland
| | - Rachel M McLoughlin
- Host Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Dublin 2, Ireland
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7
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Abstract
Nonclonal innate immune responses mediated by germ line-encoded receptors, such as Toll-like receptors or natural killer receptors, are commonly contrasted with diverse, clonotypic adaptive responses of lymphocyte antigen receptors generated by somatic recombination. However, the Variable (V) regions of antigen receptors include germ line-encoded motifs unaltered by somatic recombination, and theoretically available to mediate nonclonal, innate responses, that are independent of or largely override clonotypic responses. Recent evidence demonstrates that such responses exist, underpinning the associations of particular γδ T cell receptors (TCRs) with specific anatomical sites. Thus, TCRγδ can make innate and adaptive responses with distinct functional outcomes. Given that αβ T cells and B cells can also make nonclonal responses, we consider that innate responses of antigen receptor V-regions may be more widespread, for example, inducing states of preparedness from which adaptive clones are better selected. We likewise consider that potent, nonclonal T cell responses to microbial superantigens may reflect subversion of physiologic innate responses of TCRα/β chains.
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Affiliation(s)
- Adrian C Hayday
- Peter Gorer Department of Immunobiology, King's College, London, SE1 9RT, United Kingdom; .,Immunosurveillance Laboratory, Francis Crick Institute, London, NW1 1AT, United Kingdom
| | - Pierre Vantourout
- Peter Gorer Department of Immunobiology, King's College, London, SE1 9RT, United Kingdom; .,Immunosurveillance Laboratory, Francis Crick Institute, London, NW1 1AT, United Kingdom
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8
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TBA 225, a fusion toxoid vaccine for protection and broad neutralization of staphylococcal superantigens. Sci Rep 2019; 9:3279. [PMID: 30824769 PMCID: PMC6397225 DOI: 10.1038/s41598-019-39890-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 12/04/2018] [Indexed: 02/01/2023] Open
Abstract
Superantigens (SAgs) play a major role in the pathogenesis of Staphylococcus aureus and are associated with several diseases, including food poisoning, bacterial arthritis, and toxic shock syndrome. Monoclonal antibodies to these SAgs, primarily TSST-1, SEB and SEA have been shown to provide protection in animal studies and to reduce clinical severity in bacteremic patients. Here we quantify the pre-existing antibodies against SAgs in many human plasma and IVIG samples and demonstrate that in a major portion of the population these antibody titers are suboptimal and IVIG therapy only incrementally elevates the anti-SAg titers. Our in vitro neutralization studies show that a combination of antibodies against SEA, SEB,and TSST-1 can provide broad neutralization of staphylococcal SAgs. We report a single fusion protein (TBA225) consisting of the toxoid versions of TSST-1, SEB and SEA and demonstrate its immunogenicity and protective efficacy in a mouse model of toxic shock. Antibodies raised against this fusion vaccine provide broad neutralization of purified SAgs and culture supernatants of multiple clinically relevant S. aureus strains. Our data strongly supports the use of this fusion protein as a component of an anti-virulence based multivalent toxoid vaccine against S. aureus disease.
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9
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Tuffs SW, Haeryfar SMM, McCormick JK. Manipulation of Innate and Adaptive Immunity by Staphylococcal Superantigens. Pathogens 2018; 7:pathogens7020053. [PMID: 29843476 PMCID: PMC6027230 DOI: 10.3390/pathogens7020053] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 12/15/2022] Open
Abstract
Staphylococcal superantigens (SAgs) constitute a family of potent exotoxins secreted by Staphylococcus aureus and other select staphylococcal species. SAgs function to cross-link major histocompatibility complex (MHC) class II molecules with T cell receptors (TCRs) to stimulate the uncontrolled activation of T lymphocytes, potentially leading to severe human illnesses such as toxic shock syndrome. The ubiquity of SAgs in clinical S. aureus isolates suggests that they likely make an important contribution to the evolutionary fitness of S. aureus. Although the apparent redundancy of SAgs in S. aureus has not been explained, the high level of sequence diversity within this toxin family may allow for SAgs to recognize an assorted range of TCR and MHC class II molecules, as well as aid in the avoidance of humoral immunity. Herein, we outline the major diseases associated with the staphylococcal SAgs and how a dysregulated immune system may contribute to pathology. We then highlight recent research that considers the importance of SAgs in the pathogenesis of S. aureus infections, demonstrating that SAgs are more than simply an immunological diversion. We suggest that SAgs can act as targeted modulators that drive the immune response away from an effective response, and thus aid in S. aureus persistence.
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Affiliation(s)
- Stephen W Tuffs
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5C1, Canada.
| | - S M Mansour Haeryfar
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5C1, Canada.
- Division of Clinical Immunology and Allergy, Department of Medicine, Western University, London, ON N6A 3K7, Canada.
- Centre for Human Immunology, Western University, London, ON N6A 3K7, Canada.
- Lawson Health Research Institute, London, ON N6C 2R5, Canada.
| | - John K McCormick
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5C1, Canada.
- Centre for Human Immunology, Western University, London, ON N6A 3K7, Canada.
- Lawson Health Research Institute, London, ON N6C 2R5, Canada.
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10
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Fisher EL, Otto M, Cheung GYC. Basis of Virulence in Enterotoxin-Mediated Staphylococcal Food Poisoning. Front Microbiol 2018; 9:436. [PMID: 29662470 PMCID: PMC5890119 DOI: 10.3389/fmicb.2018.00436] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/26/2018] [Indexed: 12/17/2022] Open
Abstract
The Staphylococcus aureus enterotoxins are a superfamily of secreted virulence factors that share structural and functional similarities and possess potent superantigenic activity causing disruptions in adaptive immunity. The enterotoxins can be separated into two groups; the classical (SEA-SEE) and the newer (SEG-SElY and counting) enterotoxin groups. Many members from both these groups contribute to the pathogenesis of several serious human diseases, including toxic shock syndrome, pneumonia, and sepsis-related infections. Additionally, many members demonstrate emetic activity and are frequently responsible for food poisoning outbreaks. Due to their robust tolerance to denaturing, the enterotoxins retain activity in food contaminated previously with S. aureus. The genes encoding the enterotoxins are found mostly on a variety of different mobile genetic elements. Therefore, the presence of enterotoxins can vary widely among different S. aureus isolates. Additionally, the enterotoxins are regulated by multiple, and often overlapping, regulatory pathways, which are influenced by environmental factors. In this review, we also will focus on the newer enterotoxins (SEG-SElY), which matter for the role of S. aureus as an enteropathogen, and summarize our current knowledge on their prevalence in recent food poisoning outbreaks. Finally, we will review the current literature regarding the key elements that govern the complex regulation of enterotoxins, the molecular mechanisms underlying their enterotoxigenic, superantigenic, and immunomodulatory functions, and discuss how these activities may collectively contribute to the overall manifestation of staphylococcal food poisoning.
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Affiliation(s)
- Emilie L Fisher
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Gordon Y C Cheung
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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11
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Streptococcal pharyngitis and rheumatic heart disease: the superantigen hypothesis revisited. INFECTION GENETICS AND EVOLUTION 2018. [PMID: 29530660 DOI: 10.1016/j.meegid.2018.03.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Streptococcus pyogenes is a human-specific and globally prominent bacterial pathogen that despite causing numerous human infections, this bacterium is normally found in an asymptomatic carrier state. This review provides an overview of both bacterial and human factors that likely play an important role in nasopharyngeal colonization and pharyngitis, as well as the development of acute rheumatic fever and rheumatic heart disease. Here we highlight a recently described role for bacterial superantigens in promoting acute nasopharyngeal infection, and discuss how these immune system activating toxins could be crucial to initiate the autoimmune process in rheumatic heart disease.
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12
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Vermijlen D, Gatti D, Kouzeli A, Rus T, Eberl M. γδ T cell responses: How many ligands will it take till we know? Semin Cell Dev Biol 2018; 84:75-86. [PMID: 29402644 DOI: 10.1016/j.semcdb.2017.10.009] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 09/06/2017] [Accepted: 10/09/2017] [Indexed: 12/20/2022]
Abstract
γδ T cells constitute a sizeable and non-redundant fraction of the total T cell pool in all jawed vertebrates, but in contrast to conventional αβ T cells they are not restricted by classical MHC molecules. Progress in our understanding of the role of γδ T cells in the immune system has been hampered, and is being hampered, by the considerable lack of knowledge regarding the antigens γδ T cells respond to. The past few years have seen a wealth of data regarding the TCR repertoires of distinct γδ T cell populations and a growing list of confirmed and proposed molecules that are recognised by γδ T cells in different species. Yet, the physiological contexts underlying the often restricted TCR usage and the chemical diversity of γδ T cell ligands remain largely unclear, and only few structural studies have confirmed direct ligand recognition by the TCR. We here review the latest progress in the identification and validation of putative γδ T cell ligands and discuss the implications of such findings for γδ T cell responses in health and disease.
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Affiliation(s)
- David Vermijlen
- Department of Pharmacotherapy and Pharmaceutics and Institute for Medical Immunology, Université Libre de Bruxelles (ULB), Belgium.
| | - Deborah Gatti
- Department of Pharmacotherapy and Pharmaceutics and Institute for Medical Immunology, Université Libre de Bruxelles (ULB), Belgium
| | - Ariadni Kouzeli
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Teja Rus
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Matthias Eberl
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom; Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom.
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13
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Shaler CR, Choi J, Rudak PT, Memarnejadian A, Szabo PA, Tun-Abraham ME, Rossjohn J, Corbett AJ, McCluskey J, McCormick JK, Lantz O, Hernandez-Alejandro R, Haeryfar SM. MAIT cells launch a rapid, robust and distinct hyperinflammatory response to bacterial superantigens and quickly acquire an anergic phenotype that impedes their cognate antimicrobial function: Defining a novel mechanism of superantigen-induced immunopathology and immunosuppression. PLoS Biol 2017. [PMID: 28632753 PMCID: PMC5478099 DOI: 10.1371/journal.pbio.2001930] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Superantigens (SAgs) are potent exotoxins secreted by Staphylococcus aureus and Streptococcus pyogenes. They target a large fraction of T cell pools to set in motion a "cytokine storm" with severe and sometimes life-threatening consequences typically encountered in toxic shock syndrome (TSS). Given the rapidity with which TSS develops, designing timely and truly targeted therapies for this syndrome requires identification of key mediators of the cytokine storm's initial wave. Equally important, early host responses to SAgs can be accompanied or followed by a state of immunosuppression, which in turn jeopardizes the host's ability to combat and clear infections. Unlike in mouse models, the mechanisms underlying SAg-associated immunosuppression in humans are ill-defined. In this work, we have identified a population of innate-like T cells, called mucosa-associated invariant T (MAIT) cells, as the most powerful source of pro-inflammatory cytokines after exposure to SAgs. We have utilized primary human peripheral blood and hepatic mononuclear cells, mouse MAIT hybridoma lines, HLA-DR4-transgenic mice, MAIThighHLA-DR4+ bone marrow chimeras, and humanized NOD-scid IL-2Rγnull mice to demonstrate for the first time that: i) mouse and human MAIT cells are hyperresponsive to SAgs, typified by staphylococcal enterotoxin B (SEB); ii) the human MAIT cell response to SEB is rapid and far greater in magnitude than that launched by unfractionated conventional T, invariant natural killer T (iNKT) or γδ T cells, and is characterized by production of interferon (IFN)-γ, tumor necrosis factor (TNF)-α and interleukin (IL)-2, but not IL-17A; iii) high-affinity MHC class II interaction with SAgs, but not MHC-related protein 1 (MR1) participation, is required for MAIT cell activation; iv) MAIT cell responses to SEB can occur in a T cell receptor (TCR) Vβ-specific manner but are largely contributed by IL-12 and IL-18; v) as MAIT cells are primed by SAgs, they also begin to develop a molecular signature consistent with exhaustion and failure to participate in antimicrobial defense. Accordingly, they upregulate lymphocyte-activation gene 3 (LAG-3), T cell immunoglobulin and mucin-3 (TIM-3), and/or programmed cell death-1 (PD-1), and acquire an anergic phenotype that interferes with their cognate function against Klebsiella pneumoniae and Escherichia coli; vi) MAIT cell hyperactivation and anergy co-utilize a signaling pathway that is governed by p38 and MEK1/2. Collectively, our findings demonstrate a pathogenic, rather than protective, role for MAIT cells during infection. Furthermore, we propose a novel mechanism of SAg-associated immunosuppression in humans. MAIT cells may therefore provide an attractive therapeutic target for the management of both early and late phases of severe SAg-mediated illnesses.
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MESH Headings
- Animals
- Antigens, Bacterial/metabolism
- Antigens, Bacterial/toxicity
- Bone Marrow Cells/cytology
- Bone Marrow Cells/drug effects
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- Cell Line
- Cells, Cultured
- Clonal Anergy/drug effects
- Crosses, Genetic
- Enterotoxins/metabolism
- Enterotoxins/toxicity
- Female
- Humans
- Hybridomas
- Immunity, Innate
- Leukocytes, Mononuclear/cytology
- Leukocytes, Mononuclear/drug effects
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/metabolism
- Lymphocyte Activation/drug effects
- Mice
- Mice, Inbred NOD
- Mice, Knockout
- Mice, SCID
- Mice, Transgenic
- Models, Immunological
- Mucosal-Associated Invariant T Cells/cytology
- Mucosal-Associated Invariant T Cells/drug effects
- Mucosal-Associated Invariant T Cells/immunology
- Mucosal-Associated Invariant T Cells/metabolism
- Specific Pathogen-Free Organisms
- Staphylococcus aureus/immunology
- Staphylococcus aureus/metabolism
- Streptococcus pyogenes/immunology
- Streptococcus pyogenes/metabolism
- Superantigens/metabolism
- Superantigens/toxicity
- Transplantation Chimera/blood
- Transplantation Chimera/immunology
- Transplantation Chimera/metabolism
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Affiliation(s)
- Christopher R. Shaler
- Department of Microbiology and Immunology, Western University, London, Ontario, Canada
| | - Joshua Choi
- Department of Microbiology and Immunology, Western University, London, Ontario, Canada
| | - Patrick T. Rudak
- Department of Microbiology and Immunology, Western University, London, Ontario, Canada
| | - Arash Memarnejadian
- Department of Microbiology and Immunology, Western University, London, Ontario, Canada
| | - Peter A. Szabo
- Department of Microbiology and Immunology, Western University, London, Ontario, Canada
| | - Mauro E. Tun-Abraham
- Division of General Surgery, Department of Surgery, Western University, London, Ontario, Canada
| | - Jamie Rossjohn
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
- Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Alexandra J. Corbett
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria, Australia
| | - James McCluskey
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria, Australia
| | - John K. McCormick
- Department of Microbiology and Immunology, Western University, London, Ontario, Canada
- Centre for Human Immunology, Western University, London, Ontario, Canada
- Lawson Health Research Institute, London, Ontario, Canada
| | - Olivier Lantz
- Laboratoire d'Immunologie and INSERM U932, Institut Curie, Paris, France
| | - Roberto Hernandez-Alejandro
- Division of General Surgery, Department of Surgery, Western University, London, Ontario, Canada
- Division of Transplantation, Department of Surgery, University of Rochester Medical Center, Rochester, New York, United States of America
| | - S.M. Mansour Haeryfar
- Department of Microbiology and Immunology, Western University, London, Ontario, Canada
- Centre for Human Immunology, Western University, London, Ontario, Canada
- Lawson Health Research Institute, London, Ontario, Canada
- Division of Clinical Immunology and Allergy, Department of Medicine, Western University, London, Ontario, Canada
- * E-mail:
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14
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Human γδT-cell subsets and their involvement in tumor immunity. Cell Mol Immunol 2016; 14:245-253. [PMID: 27890919 PMCID: PMC5360884 DOI: 10.1038/cmi.2016.55] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/22/2016] [Accepted: 08/23/2016] [Indexed: 12/14/2022] Open
Abstract
γδT cells are a conserved population of innate lymphocytes with diverse structural and functional heterogeneity that participate in various immune responses during tumor progression. γδT cells perform potent immunosurveillance by exerting direct cytotoxicity, strong cytokine production and indirect antitumor immune responses. However, certain γδT-cell subsets also contribute to tumor progression by facilitating cancer-related inflammation and immunosuppression. Here, we review recent observations regarding the antitumor and protumor roles of major structural and functional subsets of human γδT cells, describing how these subsets are activated and polarized, and how these events relate to subsequent function in tumor immunity. These studies provide insights into the manipulation of γδT-cell function to facilitate more targeted approaches for tumor therapy.
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15
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Liuzzi AR, Kift-Morgan A, Lopez-Anton M, Friberg IM, Zhang J, Brook AC, Roberts GW, Donovan KL, Colmont CS, Toleman MA, Bowen T, Johnson DW, Topley N, Moser B, Fraser DJ, Eberl M. Unconventional Human T Cells Accumulate at the Site of Infection in Response to Microbial Ligands and Induce Local Tissue Remodeling. THE JOURNAL OF IMMUNOLOGY 2016; 197:2195-207. [PMID: 27527598 PMCID: PMC5009878 DOI: 10.4049/jimmunol.1600990] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 07/12/2016] [Indexed: 12/13/2022]
Abstract
The antimicrobial responsiveness and function of unconventional human T cells are poorly understood, with only limited access to relevant specimens from sites of infection. Peritonitis is a common and serious complication in individuals with end-stage kidney disease receiving peritoneal dialysis. By analyzing local and systemic immune responses in peritoneal dialysis patients presenting with acute bacterial peritonitis and monitoring individuals before and during defined infectious episodes, our data show that Vγ9/Vδ2+ γδ T cells and mucosal-associated invariant T cells accumulate at the site of infection with organisms producing (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate and vitamin B2, respectively. Such unconventional human T cells are major producers of IFN-γ and TNF-α in response to these ligands that are shared by many microbial pathogens and affect the cells lining the peritoneal cavity by triggering local inflammation and inducing tissue remodeling with consequences for peritoneal membrane integrity. Our data uncover a crucial role for Vγ9/Vδ2 T cells and mucosal-associated invariant T cells in bacterial infection and suggest that they represent a useful predictive marker for important clinical outcomes, which may inform future stratification and patient management. These findings are likely to be applicable to other acute infections where local activation of unconventional T cells contributes to the antimicrobial inflammatory response.
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Affiliation(s)
- Anna Rita Liuzzi
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Ann Kift-Morgan
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Melisa Lopez-Anton
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom; Wales Kidney Research Unit, Heath Park Campus, Cardiff CF14 4XN, United Kingdom
| | - Ida M Friberg
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Jingjing Zhang
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Amy C Brook
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Gareth W Roberts
- Wales Kidney Research Unit, Heath Park Campus, Cardiff CF14 4XN, United Kingdom; Directorate of Nephrology and Transplantation, Cardiff and Vale University Health Board, University Hospital of Wales, Cardiff CF14 4XW, United Kingdom
| | - Kieron L Donovan
- Wales Kidney Research Unit, Heath Park Campus, Cardiff CF14 4XN, United Kingdom; Directorate of Nephrology and Transplantation, Cardiff and Vale University Health Board, University Hospital of Wales, Cardiff CF14 4XW, United Kingdom
| | - Chantal S Colmont
- Wales Kidney Research Unit, Heath Park Campus, Cardiff CF14 4XN, United Kingdom
| | - Mark A Toleman
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Timothy Bowen
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom; Wales Kidney Research Unit, Heath Park Campus, Cardiff CF14 4XN, United Kingdom
| | - David W Johnson
- Department of Renal Medicine, University of Queensland at Princess Alexandra Hospital, Brisbane, Queensland 4102, Australia; Centre for Kidney Disease Research, Translational Research Institute, Brisbane, Queensland 4102, Australia; Australia and New Zealand Dialysis and Transplant Registry, Adelaide, South Australia 5001, Australia
| | - Nicholas Topley
- Centre for Medical Education, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom; and Systems Immunity Research Institute, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Bernhard Moser
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom; Systems Immunity Research Institute, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Donald J Fraser
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom; Wales Kidney Research Unit, Heath Park Campus, Cardiff CF14 4XN, United Kingdom; Directorate of Nephrology and Transplantation, Cardiff and Vale University Health Board, University Hospital of Wales, Cardiff CF14 4XW, United Kingdom; Systems Immunity Research Institute, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Matthias Eberl
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom; Systems Immunity Research Institute, Cardiff University, Cardiff CF14 4XN, United Kingdom
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16
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Christopoulos P, Bukatz D, Kock S, Malkovsky M, Finke J, Fisch P. Improved analysis of TCRγδ variable region expression in humans. J Immunol Methods 2016; 434:66-72. [DOI: 10.1016/j.jim.2016.04.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/20/2016] [Accepted: 04/20/2016] [Indexed: 01/13/2023]
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17
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Wang H, Morita CT. Sensor Function for Butyrophilin 3A1 in Prenyl Pyrophosphate Stimulation of Human Vγ2Vδ2 T Cells. THE JOURNAL OF IMMUNOLOGY 2015; 195:4583-94. [PMID: 26475929 DOI: 10.4049/jimmunol.1500314] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 09/15/2015] [Indexed: 11/19/2022]
Abstract
Vγ2Vδ2 T cells play important roles in human immunity to pathogens and in cancer immunotherapy by responding to isoprenoid metabolites, such as (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate and isopentenyl pyrophosphate. The Ig superfamily protein butyrophilin (BTN)3A1 was shown to be required for prenyl pyrophosphate stimulation. We proposed that the intracellular B30.2 domain of BTN3A1 binds prenyl pyrophosphates, resulting in a change in the extracellular BTN3A1 dimer that is detected by Vγ2Vδ2 TCRs. Such B30.2 binding was demonstrated recently. However, other investigators reported that the extracellular BTN3A1 IgV domain binds prenyl pyrophosphates, leading to the proposal that the Vγ2Vδ2 TCR recognizes the complex. To distinguish between these mechanisms, we mutagenized residues in the two binding sites and tested the mutant BTN3A1 proteins for their ability to mediate prenyl pyrophosphate stimulation of Vγ2Vδ2 T cells to proliferate and secrete TNF-α. Mutagenesis of residues in the IgV site had no effect on Vγ2Vδ2 T cell proliferation or secretion of TNF-α. In contrast, mutagenesis of residues within the basic pocket and surrounding V regions of the B30.2 domain abrogated prenyl pyrophosphate-induced proliferation. Mutations of residues making hydrogen bonds to the pyrophosphate moiety also abrogated TNF-α secretion, as did mutation of aromatic residues making contact with the alkenyl chain. Some mutations further from the B30.2 binding site also diminished stimulation, suggesting that the B30.2 domain may interact with a second protein. These findings support intracellular sensing of prenyl pyrophosphates by BTN3A1 rather than extracellular presentation.
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Affiliation(s)
- Hong Wang
- Division of Immunology, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA 52242; Department of Veterans Affairs, Iowa City Health Care System, Iowa City, IA 52246; and
| | - Craig T Morita
- Division of Immunology, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA 52242; Department of Veterans Affairs, Iowa City Health Care System, Iowa City, IA 52246; and Interdisciplinary Graduate Program in Immunology, University of Iowa Carver College of Medicine, Iowa City, IA 52242
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18
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Wang H, Henry O, Distefano MD, Wang YC, Räikkönen J, Mönkkönen J, Tanaka Y, Morita CT. Butyrophilin 3A1 plays an essential role in prenyl pyrophosphate stimulation of human Vγ2Vδ2 T cells. THE JOURNAL OF IMMUNOLOGY 2013; 191:1029-42. [PMID: 23833237 DOI: 10.4049/jimmunol.1300658] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Most human γδ T cells express Vγ2Vδ2 TCRs and play important roles in microbial and tumor immunity. Vγ2Vδ2 T cells are stimulated by self- and foreign prenyl pyrophosphate intermediates in isoprenoid synthesis. However, little is known about the molecular basis for this stimulation. We find that a mAb specific for butyrophilin 3 (BTN3)/CD277 Ig superfamily proteins mimics prenyl pyrophosphates. The 20.1 mAb stimulated Vγ2Vδ2 T cell clones regardless of their functional phenotype or developmental origin and selectively expanded blood Vγ2Vδ2 T cells. The γδ TCR mediates 20.1 mAb stimulation because IL-2 is released by β(-) Jurkat cells transfected with Vγ2Vδ2 TCRs. 20.1 stimulation was not due to isopentenyl pyrophosphate (IPP) accumulation because 20.1 treatment of APC did not increase IPP levels. In addition, stimulation was not inhibited by statin treatment, which blocks IPP production. Importantly, small interfering RNA knockdown of BTN3A1 abolished stimulation by IPP that could be restored by re-expression of BTN3A1 but not by BTN3A2 or BTN3A3. Rhesus monkey and baboon APC presented HMBPP and 20.1 to human Vγ2Vδ2 T cells despite amino acid differences in BTN3A1 that localize to its outer surface. This suggests that the conserved inner and/or top surfaces of BTN3A1 interact with its counterreceptor. Although no binding site exists on the BTN3A1 extracellular domains, a model of the intracellular B30.2 domain predicts a basic pocket on its binding surface. However, BTN3A1 did not preferentially bind a photoaffinity prenyl pyrophosphate. Thus, BTN3A1 is required for stimulation by prenyl pyrophosphates but does not bind the intermediates with high affinity.
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Affiliation(s)
- Hong Wang
- Division of Immunology, Department of Internal Medicine, Interdisciplinary Graduate Program in Immunology, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA
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19
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Cunningham AL, Harman A, Kim M, Nasr N, Lai J. Immunobiology of dendritic cells and the influence of HIV infection. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 762:1-44. [PMID: 22975870 DOI: 10.1007/978-1-4614-4433-6_1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Recent progress in phenotyping of human dendritic cells (DCs) has allowed a closer alignment of the classification and functions of murine and human dendritic cell subsets. Marked differences in the functions of these human DC subsets and their response to HIV infection have become apparent, relevant to HIV pathogenesis and vaccine and microbicide development. Systems biology approaches to studying HIV uptake and infection of dendritic cells has revealed how markedly HIV subverts their functions, especially in relation to the trafficking pathways and viral transfer to T cells. Furthermore the interactions between DCs and other innate immune cells, NK cells, NKT cells and gamma delta T cells are now known to influence DC and T cell function and are also disturbed by HIV infection in vitro and in vivo. Such cellular interactions are potential targets for vaccine adjuvants and immunotherapy.
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20
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Wang H, Sarikonda G, Puan KJ, Tanaka Y, Feng J, Giner JL, Cao R, Mönkkönen J, Oldfield E, Morita CT. Indirect stimulation of human Vγ2Vδ2 T cells through alterations in isoprenoid metabolism. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 187:5099-113. [PMID: 22013129 PMCID: PMC3326638 DOI: 10.4049/jimmunol.1002697] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Human Vγ2Vδ2 T cells monitor isoprenoid metabolism by recognizing (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), an intermediate in the 2-C-methyl-d-erythritol-4-phosphate pathway used by microbes, and isopentenyl pyrophosphate (IPP), an intermediate in the mevalonate pathway used by humans. Aminobisphosphonates and alkylamines indirectly stimulate Vγ2Vδ2 cells by inhibiting farnesyl diphosphate synthase (FDPS) in the mevalonate pathway, thereby increasing IPP/triphosphoric acid 1-adenosin-5'-yl ester 3-(3-methylbut-3-enyl) ester that directly stimulate. In this study, we further characterize stimulation by these compounds and define pathways used by new classes of compounds. Consistent with FDPS inhibition, stimulation of Vγ2Vδ2 cells by aminobisphosphonates and alkylamines was much more sensitive to statin inhibition than stimulation by prenyl pyrophosphates; however, the continuous presence of aminobisphosphonates was toxic for T cells and blocked their proliferation. Aminobisphosphonate stimulation was rapid and prolonged, independent of known Ag-presenting molecules, and resistant to fixation. New classes of stimulatory compounds-mevalonate, the alcohol of HMBPP, and alkenyl phosphonates-likely stimulate differently. Mevalonate, a rate-limiting metabolite, appears to enter cells to increase IPP levels, whereas the alcohol of HMBPP and alkenyl phosphonates are directly recognized. The critical chemical feature of bisphosphonates is the amino moiety, because its loss switched aminobisphosphonates to direct Ags. Transfection of APCs with small interfering RNA downregulating FDPS rendered them stimulatory for Vγ2Vδ2 cells and increased cellular IPP. Small interfering RNAs for isopentenyl diphosphate isomerase functioned similarly. Our results show that a variety of manipulations affecting isoprenoid metabolism lead to stimulation of Vγ2Vδ2 T cells and that pulsing aminobisphosphonates would be more effective for the ex vivo expansion of Vγ2Vδ2 T cells for adoptive cancer immunotherapy.
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Affiliation(s)
- Hong Wang
- Division of Immunology, Department of Internal Medicine, Interdisciplinary Graduate Program in Immunology, University of Iowa Carver College of Medicine, Veterans Affairs Medical Center, EMRB 400F, Iowa City, IA 52242
| | - Ghanashyam Sarikonda
- Division of Immunology, Department of Internal Medicine, Interdisciplinary Graduate Program in Immunology, University of Iowa Carver College of Medicine, Veterans Affairs Medical Center, EMRB 400F, Iowa City, IA 52242
| | - Kia-Joo Puan
- Division of Immunology, Department of Internal Medicine, Interdisciplinary Graduate Program in Immunology, University of Iowa Carver College of Medicine, Veterans Affairs Medical Center, EMRB 400F, Iowa City, IA 52242
| | - Yoshimasa Tanaka
- Center for Innovation in Immunoregulative Technology and Therapeutics, Graduate School of Medicine, Kyoto University, Sakyo, Kyoto 606-8501
| | - Ju Feng
- Department of Chemistry, State University of New York-ESF, Syracuse, NY 13210
| | - José-Luis Giner
- Department of Chemistry, State University of New York-ESF, Syracuse, NY 13210
| | - Rong Cao
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801
| | - Jukka Mönkkönen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Eric Oldfield
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801
| | - Craig T. Morita
- Division of Immunology, Department of Internal Medicine, Interdisciplinary Graduate Program in Immunology, University of Iowa Carver College of Medicine, Veterans Affairs Medical Center, EMRB 400F, Iowa City, IA 52242
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21
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Hayworth JL, Mazzuca DM, Maleki Vareki S, Welch I, McCormick JK, Haeryfar SMM. CD1d-independent activation of mouse and human iNKT cells by bacterial superantigens. Immunol Cell Biol 2011; 90:699-709. [PMID: 22041925 DOI: 10.1038/icb.2011.90] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Invariant NKT (iNKT) cells are infrequent but important immunomodulatory lymphocytes that exhibit CD1d-restricted reactivity with glycolipid Ags. iNKT cells express a unique T-cell receptor (TCR) composed of an invariant α-chain, paired with a limited range of β-chains. Superantigens (SAgs) are microbial toxins defined by their ability to activate conventional T cells in a TCR β-chain variable domain (Vβ)-specific manner. However, whether iNKT cells are directly activated by bacterial SAgs remains an open question. Herein, we explored the responsiveness of mouse and human iNKT cells to a panel of staphylococcal and streptococcal SAgs and examined the contribution of major histocompatibility complex (MHC) class II and CD1d to these responses. Bacterial SAgs that target mouse Vβ8, such as staphylococcal enterotoxin B (SEB), were able to activate mouse hybridoma and primary hepatic iNKT cells in the presence of mouse APCs expressing human leukocyte antigen (HLA)-DR4. iNKT cell-mediated cytokine secretion in SEB-challenged HLA-DR4-transgenic mice was CD1d-independent and accompanied by a high interferon-γ:interleukin-4 ratio consistent with an in vivo Th1 bias. Furthermore, iNKT cells from SEB-injected HLA-DR4-transgenic mice, and iNKT cells from SEB-treated human PBMCs, showed early activation by intracellular cytokine staining and CD69 expression. Unlike iNKT cell stimulation by α-galactosylceramide, stimulation by SEB did not induce TCR downregulation of either mouse or human iNKT cells. We conclude that Vβ8-targeting bacterial SAgs can activate iNKT cells by utilizing a novel pathway that requires MHC class II interactions, but not CD1d. Therefore, iNKT cells fulfill important effector functions in response to bacterial SAgs and may provide attractive targets in the management of SAg-induced illnesses.
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Affiliation(s)
- Jacqueline L Hayworth
- Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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22
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Jiang Y, Tang F, Li Z, Cui L, He W. Critical role of γ4 chain in the expression of functional Vγ4Vδ1 T cell receptor of gastric tumour-infiltrating γδT lymphocytes. Scand J Immunol 2011; 75:102-8. [PMID: 21988289 DOI: 10.1111/j.1365-3083.2011.02634.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Vγ4Vδ1 T cell receptor (TCRγ4δ1)-expressing γδT cells were the most dominant subset in gastric tumour-infiltrating γδT cells (γδTIL) we recently analyzed. To study the essential roles of γ and δ chains in assembly and function of TCRγ4δ1, we sequenced and constructed them into lentiviral vectors for the reconstitution of TCRγ4δ1 using different modalities of transduction. We were able to efficiently reconstitute TCRγ4δ1 with functional activities when both γ4 and δ1 chains are coexpressed in TCR-negative J.RT3-T3.5 cells. However, the expression of δ1 chain is greatly diminished when γ4 expression is absent, suggesting that the coexpressing γ4 is critical in maintaining the folding and stability of δ1 product. To functionally study the reconstituted TCRγ4δ1, we examined the cytolytic activity of TCRγ4δ1-reconstituted J.RT3-T3.5 cells and cytokine secretion and found the receptors are fully functional, but their functionality also requires the presence of γ4. Our results demonstrated that γ4 is critical for the stability of δ1 and the function of TCRγ4δ1.
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Affiliation(s)
- Y Jiang
- Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine, Peking Union Medical College, National Key Laboratory of Medical Molecular Biology, Beijing, China
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23
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Wang H, Fang Z, Morita CT. Vgamma2Vdelta2 T Cell Receptor recognition of prenyl pyrophosphates is dependent on all CDRs. THE JOURNAL OF IMMUNOLOGY 2010; 184:6209-22. [PMID: 20483784 DOI: 10.4049/jimmunol.1000231] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
gammadelta T cells differ from alphabeta T cells in the Ags they recognize and their functions in immunity. Although most alphabeta TCRs recognize peptides presented by MHC class I or II, human gammadelta T cells expressing Vgamma2Vdelta2 TCRs recognize nonpeptide prenyl pyrophosphates. To define the molecular basis for this recognition, the effect of mutations in the TCR CDR was assessed. Mutations in all CDR loops altered recognition and cover a large footprint. Unlike murine gammadelta TCR recognition of the MHC class Ib T22 protein, there was no CDR3delta motif required for recognition because only one residue is required. Instead, the length and sequence of CDR3gamma was key. Although a prenyl pyrophosphate-binding site was defined by Lys109 in Jgamma1.2 and Arg51 in CDR2delta, the area outlined by critical mutations is much larger. These results show that prenyl pyrophosphate recognition is primarily by germline-encoded regions of the gammadelta TCR, allowing a high proportion of Vgamma2Vdelta2 TCRs to respond. This underscores its parallels to innate immune receptors. Our results also provide strong evidence for the existence of an Ag-presenting molecule for prenyl pyrophosphates.
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Affiliation(s)
- Hong Wang
- Division of Rheumatology, Department of Internal Medicine, Interdisciplinary Graduate Program in Immunology, University of Iowa College of Medicine, Iowa City, IA 52242, USA
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24
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Sarikonda G, Wang H, Puan KJ, Liu XH, Lee HK, Song Y, Distefano MD, Oldfield E, Prestwich GD, Morita CT. Photoaffinity antigens for human gammadelta T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2008; 181:7738-50. [PMID: 19017963 PMCID: PMC2696061 DOI: 10.4049/jimmunol.181.11.7738] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Vgamma2Vdelta2 T cells comprise the major subset of peripheral blood gammadelta T cells in humans and expand during infections by recognizing small nonpeptide prenyl pyrophosphates. These molecules include (E)-4-hydroxy-3-methyl-but-2-enyl-pyrophosphate (HMBPP), a microbial isoprenoid intermediate, and isopentenyl pyrophosphate, an endogenous isoprenoid intermediate. Recognition of these nonpeptide Ags is mediated by the Vgamma2Vdelta2 T cell Ag receptor. Several findings suggest that prenyl pyrophosphates are presented by an Ag-presenting molecule: contact between T cells and APC is required, the Ags do not bind the Vgamma2Vdelta2 TCR directly, and Ag recognition is abrogated by TCR mutations in CDRs distant from the putative Ag recognition site. Identification of the putative Ag-presenting molecule, however, has been hindered by the inability to achieve stable association of nonpeptide prenyl pyrophosphate Ags with the presenting molecule. In this study, we show that photoaffinity analogues of HMBPP, meta/para-benzophenone-(methylene)-prenyl pyrophosphates (m/p-BZ-(C)-C(5)-OPP), can crosslink to the surface of tumor cell lines and be presented as Ags to gammadelta T cells. Mutant tumor cell lines lacking MHC class I, MHC class II, beta(2)-microglobulin, and CD1, as well as tumor cell lines from a variety of tissues and individuals, will all crosslink to and present m-BZ-C(5)-OPP. Finally, pulsing of BZ-(C)-C(5)-OPP is inhibited by isopentenyl pyrophosphate and an inactive analog, suggesting that they bind to the same molecule. Taken together, these results suggest that nonpeptide Ags are presented by a novel-Ag-presenting molecule that is widely distributed and nonpolymorphic, but not classical MHC class I, MHC class II, or CD1.
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Affiliation(s)
- Ghanashyam Sarikonda
- Division of Rheumatology, Department of Internal Medicine, University of Iowa College of Medicine, EMRB 400F, Iowa City, IA 52242 USA
- Interdisciplinary Graduate Program in Immunology, University of Iowa College of Medicine, EMRB 400F, Iowa City, IA 52242 USA
| | - Hong Wang
- Division of Rheumatology, Department of Internal Medicine, University of Iowa College of Medicine, EMRB 400F, Iowa City, IA 52242 USA
| | - Kia-Joo Puan
- Division of Rheumatology, Department of Internal Medicine, University of Iowa College of Medicine, EMRB 400F, Iowa City, IA 52242 USA
| | - Xiao-hui Liu
- Department of Medicinal Chemistry, University of Utah School of Pharmacy, Salt Lake City, UT 84112 USA
| | - Hoi K. Lee
- Division of Rheumatology, Department of Internal Medicine, University of Iowa College of Medicine, EMRB 400F, Iowa City, IA 52242 USA
| | - Yongcheng Song
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801 and the Center for Biophysics and Computational Biology, 607 South Mathews Avenue, Urbana, Illinois 61801 USA
| | - Mark D. Distefano
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455 USA
| | - Eric Oldfield
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801 and the Center for Biophysics and Computational Biology, 607 South Mathews Avenue, Urbana, Illinois 61801 USA
| | - Glenn D. Prestwich
- Department of Medicinal Chemistry, University of Utah School of Pharmacy, Salt Lake City, UT 84112 USA
| | - Craig T. Morita
- Division of Rheumatology, Department of Internal Medicine, University of Iowa College of Medicine, EMRB 400F, Iowa City, IA 52242 USA
- Interdisciplinary Graduate Program in Immunology, University of Iowa College of Medicine, EMRB 400F, Iowa City, IA 52242 USA
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25
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Integrins alpha1beta1 and alpha2beta1 are receptors for the rotavirus enterotoxin. Proc Natl Acad Sci U S A 2008; 105:8811-8. [PMID: 18587047 DOI: 10.1073/pnas.0803934105] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Rotavirus NSP4 is a viral enterotoxin capable of causing diarrhea in neonatal mice. This process is initiated by the binding of extracellular NSP4 to target molecule(s) on the cell surface that triggers a signaling cascade leading to diarrhea. We now report that the integrins alpha1beta1 and alpha2beta1 are receptors for NSP4. NSP4 specifically binds to the alpha1 and alpha2 I domains with apparent K(d) = 1-2.7 muM. Binding is mediated by the I domain metal ion-dependent adhesion site motif, requires Mg(2+) or Mn(2+), is abolished with EDTA, and an NSP4 point mutant, E(120)A, fails to bind alpha2 integrin I domain. NSP4 has two distinct integrin interaction domains. NSP4 amino acids 114-130 are essential for binding to the I domain, and NSP4 peptide 114-135 blocks binding of the natural ligand, collagen I, to integrin alpha2. NSP4 amino acids 131-140 are not associated with the initial binding to the I domain, but elicit signaling that leads to the spreading of attached C2C12-alpha2 cells, mouse myoblast cells stably expressing the human alpha2 integrin. NSP4 colocalizes with integrin alpha2 on the basolateral surface of rotavirus-infected polarized intestinal epithelial (Caco-2) cells as well as surrounding noninfected cells. NSP4 mutants that fail to bind or signal through integrin alpha2 were attenuated in diarrhea induction in neonatal mice. These results indicate that NSP4 interaction with integrin alpha1 and alpha2 is an important component of enterotoxin function and rotavirus pathogenesis, further distinguishing this viral virulence factor from other microbial enterotoxins.
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Reschner A, Hubert P, Delvenne P, Boniver J, Jacobs N. Innate lymphocyte and dendritic cell cross-talk: a key factor in the regulation of the immune response. Clin Exp Immunol 2008; 152:219-26. [PMID: 18336590 DOI: 10.1111/j.1365-2249.2008.03624.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Dendritic cells (DC) are specialized in the presentation of antigens and the initiation of specific immune responses. They have been involved recently in supporting innate immunity by interacting with various innate lymphocytes, such as natural killer (NK), NK T or T cell receptor (TCR)-gammadelta cells. The functional links between innate lymphocytes and DC have been investigated widely and different studies demonstrated that reciprocal activations follow on from NK/DC interactions. The cross-talk between innate cells and DC which leads to innate lymphocyte activation and DC maturation was found to be multi-directional, involving not only cell-cell contacts but also soluble factors. The final outcome of these cellular interactions may have a dramatic impact on the quality and strength of the down-stream immune responses, mainly in the context of early responses to tumour cells and infectious agents. Interestingly, DC, NK and TCR-gammadelta cells also share similar functions, such as antigen uptake and presentation, as well as cytotoxic and tumoricidal activity. In addition, NK and NK T cells have the ability to kill DC. This review will focus upon the different aspects of the cross-talk between DC and innate lymphocytes and its key role in all the steps of the immune response. These cellular interactions may be particularly critical in situations where immune surveillance requires efficient early innate responses.
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Affiliation(s)
- A Reschner
- Department of Pathology, GIGA-GAMCA/I3, B35, University of Liege, CHU of Liège, B4000 Liege, Belgium
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O'Brien RL, Roark CL, Jin N, Aydintug MK, French JD, Chain JL, Wands JM, Johnston M, Born WK. gammadelta T-cell receptors: functional correlations. Immunol Rev 2007; 215:77-88. [PMID: 17291280 DOI: 10.1111/j.1600-065x.2006.00477.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The gammadelta T-cell receptors (TCRs) are limited in their diversity, suggesting that their natural ligands may be few in number. Ligands for gammadeltaTCRs that have thus far been determined are predominantly of host rather than foreign origin. Correlations have been noted between the Vgamma and/or Vdelta genes a gammadelta T cell expresses and its functional role. The reason for these correlations is not yet known, but several different mechanisms are conceivable. One possibility is that interactions between particular TCR-V domains and ligands determine function or functional development. However, a recent study showed that at least for one ligand, receptor specificity is determined by the complementarity-determining region 3 (CDR3) component of the TCR-delta chain, regardless of the Vgamma and/or Vdelta. To determine what is required in the TCR for other specificities and to test whether recognition of certain ligands is connected to cell function, more gammadeltaTCR ligands must be defined. The use of recombinant soluble versions of gammadeltaTCRs appears to be a promising approach to finding new ligands, and recent results using this method are reviewed.
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Affiliation(s)
- Rebecca L O'Brien
- Integrated Deaprtment of Immunology, National Jewish Medical and Research Center, Denver, CO 80206, USA.
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28
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Wu Y, Farrell J, Pirmohamed M, Park BK, Naisbitt DJ. Generation and characterization of antigen-specific CD4+, CD8+, and CD4+CD8+ T-cell clones from patients with carbamazepine hypersensitivity. J Allergy Clin Immunol 2007; 119:973-81. [PMID: 17320939 DOI: 10.1016/j.jaci.2006.12.617] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Revised: 11/15/2006] [Accepted: 12/04/2006] [Indexed: 11/17/2022]
Abstract
BACKGROUND Hypersensitivity is a serious manifestation of anticonvulsant therapy characterized by infiltration of the epidermis and dermis by activated CD8(+) and CD4(+) T-cells, respectively. Attempts to characterize drug-specific CD8(+) T cells have been largely unsuccessful. OBJECTIVES The aim of these studies was to generate and characterize CD4(+), CD8(+), and CD4(+)CD8(+) T cells in patients with carbamazepine hypersensitivity. METHODS Carbamazepine-specific T-cell clones were generated from 5 patients by using modified cloning methodologies. Cell surface receptor phenotype, functionality, and mechanisms of antigen presentation were then compared. RESULTS Ninety CD4(+), 23 CD8(+), and 14 CD4(+)CD8(+) carbamazepine-specific T-cell clones were generated. CD4(+) T-cell clones proliferated vigorously with carbamazepine associated with MHC class II but exhibited little cytotoxic activity. In contrast, most CD8(+) T cells proliferated weakly but effectively killed target cells via an MHC class I or MHC class II restricted, perforin-dependent pathway. CD4(+)CD8(+) T cells displayed characteristics similar to those of CD4(+) T cells; however, drug stimulation was demonstrable in the absence of antigen-presenting cells. Carbamazepine was presented to CD4(+), CD8(+), and CD4(+)CD8(+) T cells in the absence of antigen processing. Drug stimulation resulted in the secretion of IFN-gamma and IL-5. A panel of CD11a(+)CD27(-) clones differentially expressed the receptors CXCR4, CCR4, CCR5, CCR8, CCR9, and CCR10. CONCLUSION Carbamazepine-specific CD4(+), CD8(+), and CD4(+)CD8(+) T cells exist in the peripheral circulation of hypersensitive patients, often many years after the resolution of clinical manifestations. CLINICAL IMPLICATIONS Carbamazepine-specific CD4(+), CD8(+), and CD4(+)CD8(+) T cells displaying different effector functions and homing characteristics persist in hypersensitive patients' blood for many years after resolution of clinical symptoms.
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Affiliation(s)
- Ying Wu
- Department of Pharmacology, University of Liverpool, Liverpool, UK
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Faulkner L, Cooper A, Fantino C, Altmann DM, Sriskandan S. The mechanism of superantigen-mediated toxic shock: not a simple Th1 cytokine storm. THE JOURNAL OF IMMUNOLOGY 2006; 175:6870-7. [PMID: 16272345 DOI: 10.4049/jimmunol.175.10.6870] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The profound clinical consequences of Gram-positive toxic shock are hypothesized to stem from excessive Th1 responses to superantigens. We used a new superantigen-sensitive transgenic model to explore the role of TCRalphabeta T cells in responses to staphylococcal enterotoxin B (SEB) in vitro and in two different in vivo models. The proliferative and cytokine responses of HLA-DR1 spleen cells were 100-fold more sensitive than controls and were entirely dependent on TCRalphabeta T cells. HLA-DR1 mice showed greater sensitivity in vivo to two doses of SEB with higher mortality and serum cytokines than controls. When d-galactosamine was used as a sensitizing agent with a single dose of SEB, HLA-DR1 mice died of toxic shock whereas controls did not. In this sensitized model of toxic shock there was a biphasic release of cytokines, including TNF-alpha, at 2 h and before death at 7 h. In both models, mortality and cytokine release at both time points were dependent on TCRalphabeta T cells. Anti-TNF-alpha pretreatment was protective against shock whereas anti-IFN gamma pretreatment and delayed anti-TNF-alpha treatment were not. Importantly, anti-TNF-alpha pretreatment inhibited the early TNF-alpha response but did not inhibit the later TNF-alpha burst, to which mortality has previously been attributed. Splenic T cells were shown definitively to be the major source of TNF-alpha during the acute cytokine response. Our results demonstrate unequivocally that TCRalphabeta T cells are critical for lethality in toxic shock but it is the early TNF-alpha response and not the later cytokine surge that mediates lethal shock.
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MESH Headings
- Animals
- Cytokines/biosynthesis
- Enterotoxins/toxicity
- Galactosamine/toxicity
- HLA-DR1 Antigen/genetics
- HLA-DR1 Antigen/metabolism
- Humans
- Mice
- Mice, Knockout
- Mice, Transgenic
- Receptors, Antigen, T-Cell, alpha-beta/deficiency
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Shock, Septic/etiology
- Shock, Septic/immunology
- Spleen/drug effects
- Spleen/immunology
- Superantigens/toxicity
- Th1 Cells/drug effects
- Th1 Cells/immunology
- Tumor Necrosis Factor-alpha/biosynthesis
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Affiliation(s)
- Lee Faulkner
- Department of Infectious Diseases, Imperial College London, London, United Kingdom
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30
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Cairo C, Propp N, Hebbeler AM, Colizzi V, Pauza CD. The Vgamma2/Vdelta2 T-cell repertoire in Macaca fascicularis: functional responses to phosphoantigen stimulation by the Vgamma2/Jgamma1.2 subset. Immunology 2005; 115:197-205. [PMID: 15885125 PMCID: PMC1782144 DOI: 10.1111/j.1365-2567.2005.02153.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Circulating Vgamma2/Vdelta2 T cells in human and non-human primates respond to small molecular weight non-peptidic phosphoantigens in a major histocompatibility complex (MHC)-unrestricted manner. These responses are encoded by the Vgamma2/Jgamma1.2 chain of the T-cell receptor and are positively selected during early development to create a biased repertoire in adults. We characterized the Vgamma2 chain in cynomolgus macaques (Macaca fascicularis) to develop a non-human primate model for studying the effects of infection and therapy on the circulating Vgamma2/Vdelta2 T-cell subset. The cynomolgus macaque Vgamma2 chain was highly homologous to the Vgamma2 chain from human beings and rhesus macaques (Macaca mulatta), though we noted conserved substitutions in critical residues within the CDR3 for both macaque species. Despite these substitutions, Vgamma2/Vdelta2+ T cells from cynomolgus monkeys exhibited polyclonal responses to two different phosphoantigens. Proliferative responses were observed with both isopentenylpyrophosphate and alendronate, but stronger interferon-gamma secretory responses were observed with isopentenylpyrophosphate. In vitro stimulation and expansion led to selective outgrowth of the Vgamma2/Jgamma1.2 subset, with a marked shift in the Vgamma2 spectratype. As a result of the less biased starting repertoire for Vgamma2, the cynomolgus macaque constitutes a sensitive model for examining the effects of in vitro or in vivo treatments on the Vgamma2/Vdelta2 T-cell population. Our studies establish the value of cynomolgus macaques as a model for Vgamma2/Vdelta2 T-cell responses to non-peptidic antigens, and further evidence the remarkable evolutionary conservation of this unusual, phosphoantigen-responsive T-cell subset that is found only in primate species.
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MESH Headings
- Alendronate
- Animals
- Base Sequence
- Cells, Cultured
- DNA, Complementary/genetics
- Hemiterpenes/immunology
- Interferon-gamma/biosynthesis
- Lymphocyte Activation/immunology
- Macaca fascicularis/immunology
- Models, Animal
- Molecular Sequence Data
- Organophosphorus Compounds/immunology
- Polymerase Chain Reaction/methods
- Receptors, Antigen, T-Cell, gamma-delta/analysis
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/immunology
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Sequence Alignment
- Species Specificity
- T-Lymphocyte Subsets/immunology
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31
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Cairo C, Arabito E, Landi F, Casati A, Brunetti E, Mancino G, Galli E. Analysis of circulating gammadelta T cells in children affected by IgE-associated and non-IgE-associated allergic atopic eczema/dermatitis syndrome. Clin Exp Immunol 2005; 141:116-21. [PMID: 15958077 PMCID: PMC1809419 DOI: 10.1111/j.1365-2249.2005.02813.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2005] [Indexed: 11/27/2022] Open
Abstract
Recent studies have suggested that not only alphabeta(+) T cells, but also the less common gammadelta(+) T cells may play a role as effectors and immunoregolatory cells in the development and perpetuation of allergic inflammation. The objective of this study was to focus on the role of gammadelta(+) T cells in atopic dermatitis (AD), a chronic relapsing inflammatory disease of the skin, often associated with allergic bronchial asthma. The present study employed flow cytometric analysis to compare numbers and phenotypic characteristics of gammadelta(+) T cells in the peripheral blood of children with atopic dermatitis and age-matched healthy controls. The percentage of circulating Vgamma 9Vdelta2(+) T lymphocytes was significantly increased in AD patients with respect to the age-matched controls, with a positive correlation with clinical score severity. The prevalent phenotype in both AD patients and controls was CD45RO(+), with no differences observed in the percentage of Vdelta2(+) CD45RO(+) between these groups. Conversely, memory CD45RO(+) CD62L(+) Vdelta2(+) lymphocytes were significantly lower in AD patients. Furthermore, naive circulating Vdelta2(+) T lymphocytes were significantly lower in AD children than in aged-matched controls. No correlation was observed between circulating Vgamma 9Vdelta2(+) expansion and IgE serum levels. It was concluded that an association exists between the levels of circulating gammadelta(+) T lymphocytes and atopic dermatitis, with a positive correlation with clinical score but no link with IgE serum levels. The pathophysiological role of gammadelta T lymphocytes in atopic dermatitis awaits further investigation.
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Affiliation(s)
- C Cairo
- Research Center San Pietro Hospital, Fatebenefratelli- AFaR- Rome, Italy
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32
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Hemalatha V, Srikanth P, Mallika M. SUPERANTIGENS – CONCEPTS, CLINICAL DISEASE AND THERAPY. Indian J Med Microbiol 2004. [DOI: 10.1016/s0255-0857(21)02764-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
A variety of microorganisms, nutrients or toxins are generally intrude our body through mucosal tissues or skin, where equipment for both preventing their invasions and catching their information to activate internal immune systems for adapting surroundings is arranged. Among the equipment, cells in charge of innate immunity, particularly dendritic cells (DCs), having an excellent capacity for prompt recognition of invaded pathogens via toll-like receptors (TLRs) to alert B and T cells for establishing aquired/adaptive immunity by presenting their processed antigenic fragments, have been paid great attention. These TLR-activated, antigen captured DCs are divided into two groups; one is pathogen-retaining unit and the other is pathogen-controlling unit. The latter DCs present processed antigenic molecules from the pathogens to competent alphabeta T cells together with special containers, such as class I, class II MHC and CD1 to generate specific cellular immunity. The former two MHC molecules can present processed peptide antigens, whereas the last CD1 molecule can present glycolipid/lipid antigens. In contrast, B lymphocytes that captured antigens via their specific immunoglobulin (Ig) receptors present digested peptide fragments with their class II MHC to stimulate suitable CD4(+) helper T cells which in turn secrete various cytokines to efficiently expand and maintain antibody production from that partner B cells to establish humoral immunity. These alphabeta T cells and antibodies, recognize either processed antigenic peptide or glycolipid fragments, and thus, identification of these epitopes enables us to generate artificial pathogen-specific vaccines. Based on the recent findings about precise mechanisms of antigen processing and presentation orchestrated at the surface compartment, future development of vaccines against various pathogens are discussed.
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Affiliation(s)
- Hidemi Takahashi
- Department of Microbiology and Immunology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, 113-8602, Tokyo, Japan.
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34
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McCormick JK, Tripp TJ, Llera AS, Sundberg EJ, Dinges MM, Mariuzza RA, Schlievert PM. Functional analysis of the TCR binding domain of toxic shock syndrome toxin-1 predicts further diversity in MHC class II/superantigen/TCR ternary complexes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 171:1385-92. [PMID: 12874229 DOI: 10.4049/jimmunol.171.3.1385] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Superantigens (SAGs) aberrantly alter immune system function through simultaneous interaction with lateral surfaces of MHC class II molecules on APCs and with particular variable regions of the TCR beta-chain (Vbeta). To further define the interface between the bacterial SAG toxic shock syndrome toxin-1 (TSST-1) and the TCR, we performed alanine scanning mutagenesis within the putative TCR binding region of TSST-1 along the central alpha helix adjacent to the N-terminal alpha helix and the beta7-beta9 loop as well as with two universally conserved SAG residues (Leu(137) and Tyr(144) in TSST-1). Mutants were analyzed for multiple functional activities, and various residues appeared to play minor or insignificant roles in the TCR interaction. The locations of six residues (Gly(16), Trp(116), Glu(132), His(135), Gln(136), and Gln(139)), each individually critical for functional activity as well as direct interaction with the human TCR Vbeta2.1-chain, indicate that the interface occurs in a novel region of the SAG molecule. Based on these data, a model of the MHC/TSST-1/TCR ternary complex predicts similarities seen with other characterized SAGs, although the CDR3 loop of Vbeta2.1 is probably involved in direct SAG-TCR molecular interactions, possibly contributing to the TCR Vbeta specificity of TSST-1.
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MESH Headings
- Amino Acid Substitution/genetics
- Amino Acid Substitution/immunology
- Animals
- Bacterial Toxins
- Disease Models, Animal
- Enterotoxins/chemistry
- Enterotoxins/genetics
- Enterotoxins/metabolism
- Enterotoxins/pharmacology
- Fever/immunology
- Fever/microbiology
- Histocompatibility Antigens Class II/genetics
- Histocompatibility Antigens Class II/metabolism
- Humans
- Mitogens/genetics
- Mitogens/metabolism
- Mitogens/pharmacology
- Models, Molecular
- Mutagenesis, Site-Directed
- Protein Binding/genetics
- Protein Binding/immunology
- Protein Structure, Tertiary/genetics
- Rabbits
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Shock, Septic/immunology
- Shock, Septic/microbiology
- Spleen/cytology
- Spleen/immunology
- Staphylococcus aureus/genetics
- Staphylococcus aureus/immunology
- Superantigens/chemistry
- Superantigens/genetics
- Superantigens/metabolism
- Superantigens/pharmacology
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Affiliation(s)
- John K McCormick
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
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35
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Wang H, Lee HK, Bukowski JF, Li H, Mariuzza RA, Chen ZW, Nam KH, Morita CT. Conservation of nonpeptide antigen recognition by rhesus monkey V gamma 2V delta 2 T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:3696-706. [PMID: 12646635 DOI: 10.4049/jimmunol.170.7.3696] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have previously found that monkey Vgamma2Vdelta2(+) T cells mount adaptive immune responses in response to Mycobacterium bovis bacillus Calmette-Guérin infections. We have now analyzed rhesus monkey gammadelta T cell responses to nonpeptide Ags and superantigens. Like human Vgamma2Vdelta2(+) T cells, rhesus monkey gammadelta T cells are stimulated when exposed to prenyl pyrophosphate, bisphosphonate, and alkylamine Ags. Responsiveness was limited to gammadelta T cells expressing Vgamma2Vdelta2 TCRs. Rhesus monkey Vgamma2Vdelta2(+) T cells also responded to the superantigen, staphyloccocal enterotoxin A. Sequencing of the rhesus monkey Vgamma2Vdelta2 TCR revealed a strong sequence homology to human Vgamma2Vdelta2 TCR that preserves important sequence motifs. Moreover, chimeric TCRs that pair human Vgamma2 with monkey Vdelta2 and monkey Vgamma2 with human Vdelta2 retain reactivity to nonpeptide Ags and B cell lymphomas. A molecular model of the rhesus monkey Vgamma2Vdelta2 TCR has a basic region in the complementarity-determining region 3 binding groove that is similar to that seen in the human Vgamma2Vdelta2 TCR and preserves the topology of the complementarity-determining region loops. Thus, recognition of nonpeptide prenyl pyrophosphate, bisphosphonate, and alkylamine Ags is conserved in primates suggesting that primates can provide an animal model for human gammadelta T cell Ag responses.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigen Presentation/immunology
- Antigens, Bacterial/metabolism
- Antigens, Bacterial/pharmacology
- Butylamines/immunology
- Butylamines/metabolism
- Butylamines/pharmacology
- Clone Cells
- Conserved Sequence/immunology
- Diphosphates/pharmacology
- Epitopes, T-Lymphocyte/analysis
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Fetal Blood/immunology
- Fetal Blood/metabolism
- Hemiterpenes
- Humans
- Infant, Newborn
- Lymphocyte Activation/drug effects
- Lymphocyte Activation/immunology
- Macaca mulatta
- Molecular Sequence Data
- Organophosphorus Compounds/immunology
- Organophosphorus Compounds/metabolism
- Organophosphorus Compounds/pharmacology
- Receptors, Antigen, T-Cell, gamma-delta/biosynthesis
- Receptors, Antigen, T-Cell, gamma-delta/blood
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/isolation & purification
- Recombinant Fusion Proteins/analysis
- Recombinant Fusion Proteins/immunology
- Recombinant Fusion Proteins/metabolism
- Sequence Homology, Amino Acid
- Superantigens/pharmacology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- Hong Wang
- Division of Rheumatology, Department of Internal Medicine and Interdisciplinary Group in Immunology, University of Iowa College of Medicine, Iowa City, IA 52442, USA
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36
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Alouf JE, Müller-Alouf H. Staphylococcal and streptococcal superantigens: molecular, biological and clinical aspects. Int J Med Microbiol 2003; 292:429-40. [PMID: 12635926 DOI: 10.1078/1438-4221-00232] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Superantigens (SAgs) include a class of certain bacterial and viral proteins exhibiting highly potent lymphocyte-transforming (mitogenic) activity towards human and or other mammalian T lymphocytes. Unlike conventional antigens, SAgs bind to certain regions of major histocompatibility complex (MHC) class II molecules of antigen-presenting cells (APCs) outside the classical antigen-binding groove and concomitantly bind in their native form to T cells at specific motifs of the variable region of the beta chain (Vbeta) of the T cell receptor (TcR). This interaction triggers the activation (proliferation) of the targeted T lymphocytes and leads to the in vivo or in vitro release of high amounts of various cytokines and other effectors by immune cells. Each SAg interacts specifically with a characteristic set of Vbeta motifs. The review summarizes our current knowledge on S. aureus and S. pyogenes superantigen proteins. The repertoire of the staphylococcal and streptococcal SAgs comprises 24 and 8 proteins, respectively. The staphylococcal SAgs include (i) the classical enterotoxins A, B, C (and antigenic variants), D, E, and the recently discovered enterotoxins G to Q, (ii) toxic shock syndrome toxin-1, (iii) exfoliatins A and B. The streptococcal SAgs include the classical pyrogenic exotoxins A and C and the newly identified pyrogenic toxins, G, H, I, J, SMEZ, and SSA. The structural and genomic aspects of these toxins and their molecular relatedness are described as well as the available 3-D crystal structure of some of them and that of certain of their complexes with MHC class II molecules and the TcR, respectively. The pathophysiological properties and clinical disorders related to these SAgs are reviewed.
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37
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Eberl M, Altincicek B, Kollas AK, Sanderbrand S, Bahr U, Reichenberg A, Beck E, Foster D, Wiesner J, Hintz M, Jomaa H. Accumulation of a potent gammadelta T-cell stimulator after deletion of the lytB gene in Escherichia coli. Immunology 2002; 106:200-11. [PMID: 12047749 PMCID: PMC1782719 DOI: 10.1046/j.1365-2567.2002.01414.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Activation of human Vgamma9/Vdelta2 T cells by many pathogens depends on the presence of small phosphorylated non-peptide compounds derived from the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway of isoprenoid biosynthesis. We here demonstrate that in Escherichia coli mutants deficient in lytB, an essential gene of the MEP pathway, a potent Vgamma9/Vdelta2 T-cell activator accumulates by a factor of approximately 150 compared to wild-type E. coli. The compound responsible for the strong immunogenicity of this E. coli mutant was subsequently characterized and identified as a small pyrophosphorylated metabolite, with a molecular mass of 262 Da, derived from the MEP pathway. Stimulation of human peripheral blood mononuclear cells (PBMC) with extracts prepared from the lytB-deficient E. coli mutant led to upregulation of T-cell activation markers on the surface of Vgamma9/Vdelta2 T cells as well as proliferation and expansion of Vgamma9/Vdelta2 T cells. This response was dependent on costimulatory growth factors, such as interleukin (IL)-2, IL-15 and IL-21. Significant levels of interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) were secreted in the presence of IL-2 and IL-15, but not in the presence of IL-21, demonstrating that proliferating phosphoantigen-reactive Vgamma9/Vdelta2 T cells do not necessarily produce proinflammatory cytokines.
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Affiliation(s)
- Matthias Eberl
- Biochemisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany.
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38
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Allison TJ, Garboczi DN. Structure of gammadelta T cell receptors and their recognition of non-peptide antigens. Mol Immunol 2002; 38:1051-61. [PMID: 11955597 DOI: 10.1016/s0161-5890(02)00034-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The gammadelta T cell receptors (TCRs) and alphabeta TCRs are similar in both sequence and structure; however, gammadelta+ and alphabeta+ T cells are not merely similar lymphocytes with subtly different receptors. These cell types differ in several ways, including the types of antigens recognized, the mechanism of antigen presentation and recognition and the mechanism and kinetics of downstream signaling events. gammadelta TCRs can directly recognize antigens in the form of intact proteins or non-peptidic compounds, unlike alphabeta TCRs which recognize peptide antigens bound to major histocompatibility complex molecules (MHC). One of the major classes of human gammadelta+ T cells expresses Vgamma9Vdelta2 TCRs which recognize pyrophosphomonoester, alkylamine and aminobisphosphonate antigens. This review focuses on the recently determined structure of a Vgamma9Vdelta2 TCR, with emphasis on antigen recognition and receptor signaling.
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Affiliation(s)
- Timothy J Allison
- Structural Biology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, 12441 Parklawn Drive, Rockville, MD 20852, USA
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Eiras Martínez P, León Prieto F, Roldán Santiago E, Sánchez Muñoz L, Bootello Gil A, Roy Ariño G, Camarero Salces C, Baragaño González M, Asensio Vegas A, Eiras Martínez P. Linfocitos intraepiteliales en la enfermedad celíaca. An Pediatr (Barc) 2002. [DOI: 10.1016/s1695-4033(02)77787-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Morita CT, Lee HK, Wang H, Li H, Mariuzza RA, Tanaka Y. Structural features of nonpeptide prenyl pyrophosphates that determine their antigenicity for human gamma delta T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:36-41. [PMID: 11418629 DOI: 10.4049/jimmunol.167.1.36] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Human Vgamma2Vdelta2(+) T cells proliferate in vivo during many microbial infections. We have found that Vgamma2Vdelta2(+) T cells recognize nonpeptide prenyl pyrophosphates and alkylamines. We now have defined structural features that determine the antigenicity of prenyl pyrophosphates by testing synthetic analogs for bioactivity. We find that the carbon chain closest to the pyrophosphate moiety plays the major role in determining bioactivity. Changes in this area, such as the loss of a double bond, abrogated bioactivity. The loss of a phosphate from the pyrophosphate moiety also decreased antigenicity 100- to 200-fold. However, nucleotide monophosphates could be added with minimal changes in bioactivity. Longer prenyl pyrophosphates also retained bioactivity. Despite differences in CDR3 sequence, Vgamma2Vdelta2(+) clones and a transfectant responded similarly. Ag docking into a Vgamma2Vdelta2 TCR model reveals a potential binding site in germline regions of the Vgamma2Jgamma1.2 CDR3 and Vdelta2 CDR2 loops. Thus, Vgamma2Vdelta2(+) T cells recognize a core carbon chain and pyrophosphate moiety. This recognition is relatively unaffected by additions at distal positions to the core Ag unit.
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Affiliation(s)
- C T Morita
- Division of Rheumatology, Department of Internal Medicine and the Interdisciplinary Group in Immunology, University of Iowa College of Medicine, Iowa City, IA 52242, USA.
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Allison TJ, Winter CC, Fournié JJ, Bonneville M, Garboczi DN. Structure of a human gammadelta T-cell antigen receptor. Nature 2001; 411:820-4. [PMID: 11459064 DOI: 10.1038/35081115] [Citation(s) in RCA: 207] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
T-cell antigen receptors composed of gamma and delta polypeptide chains (gammadelta TCRs) can directly recognize antigens in the form of intact proteins or non-peptide compounds, unlike alphabeta TCRs, which recognize antigens bound to major histocompatibility complex molecules (MHC). About 5% of peripheral blood T cells bear gammadelta TCRs, most of which recognize non-peptide phosphorylated antigens. Here we describe the 3.1 A resolution structure of a human gammadelta TCR from a T-cell clone that is phosphoantigen-reactive. The orientation of the variable (V) and constant (C) regions of the gammadelta TCR is unique when compared with alphabeta TCRs or antibodies, and results from an unusually small angle between the Vgamma and Cgamma domains. The complementarity-determining regions (CDRs) of the V domains exhibit a chemically reasonable binding site for phosphorylated antigens, providing a possible explanation for the canonical usage of the Vgamma9 and Vdelta2 gene segments by phosphoantigen-reactive receptors. Although the gammadelta TCR V domains are similar in overall structure to those of alphabeta TCRs, gammadelta TCR C domains are markedly different. Structural differences in Cgamma and Cdelta, and in the location of the disulphide bond between them, may enable gammadelta TCRs to form different recognition/signalling complexes than alphabeta TCRs.
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Affiliation(s)
- T J Allison
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland 20852, USA.
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