101
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Anderson CK, Brossay L. The role of MHC class Ib-restricted T cells during infection. Immunogenetics 2016; 68:677-91. [PMID: 27368413 DOI: 10.1007/s00251-016-0932-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/22/2016] [Indexed: 01/02/2023]
Abstract
Even though major histocompatibility complex (MHC) class Ia and many Ib molecules have similarities in structure, MHC class Ib molecules tend to have more specialized functions, which include the presentation of non-peptidic antigens to non-classical T cells. Likewise, non-classical T cells also have unique characteristics, including an innate-like phenotype in naïve animals and rapid effector functions. In this review, we discuss the role of MAIT and NKT cells during infection but also the contribution of less studied MHC class Ib-restricted T cells such as Qa-1-, Qa-2-, and M3-restricted T cells. We focus on describing the types of antigens presented to non-classical T cells, their response and cytokine profile following infection, as well as the overall impact of these T cells to the immune system.
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Affiliation(s)
- Courtney K Anderson
- Department of Molecular Microbiology and Immunology, Division of Biology and Medicine, Brown University, Box G-B618, Providence, RI, 02912, USA
| | - Laurent Brossay
- Department of Molecular Microbiology and Immunology, Division of Biology and Medicine, Brown University, Box G-B618, Providence, RI, 02912, USA.
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102
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Abstract
CD1- and MHC-related molecule-1 (MR1)-restricted T lymphocytes recognize nonpeptidic antigens, such as lipids and small metabolites, and account for a major fraction of circulating and tissue-resident T cells. They represent a readily activated, long-lasting population of effector cells and contribute to the early phases of immune response, orchestrating the function of other cells. This review addresses the main aspects of their immunological functions, including antigen and T cell receptor repertoires, mechanisms of nonpeptidic antigen presentation, and the current evidence for their participation in human and experimental diseases.
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Affiliation(s)
- Lucia Mori
- Department of Biomedicine, Basel University Hospital and Basel University, CH-4031 Basel, Switzerland; , , .,Singapore Immunology Network, A*STAR, 138648 Singapore
| | - Marco Lepore
- Department of Biomedicine, Basel University Hospital and Basel University, CH-4031 Basel, Switzerland; , ,
| | - Gennaro De Libero
- Department of Biomedicine, Basel University Hospital and Basel University, CH-4031 Basel, Switzerland; , , .,Singapore Immunology Network, A*STAR, 138648 Singapore
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103
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Favreau M, Vanderkerken K, Elewaut D, Venken K, Menu E. Does an NKT-cell-based immunotherapeutic approach have a future in multiple myeloma? Oncotarget 2016; 7:23128-40. [PMID: 26895468 PMCID: PMC5029615 DOI: 10.18632/oncotarget.7440] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 02/05/2016] [Indexed: 12/21/2022] Open
Abstract
Natural killer T (NKT) cells constitute a unique subset of innate-like T lymphocytes which differ from conventional T cells by recognizing lipid antigens presented by the non-polymorphic major histocompatibility complex (MHC) I-like molecule CD1d. Despite being a relatively infrequent population of lymphocytes, NKT cells can respond rapidly upon activation with glycosphingolipids by production of cytokines which aim to polarize different axes of the immune system. Due to their dual effector capacities, NKT cells can play a vital role in cancer immunity, infection, inflammation and autoimmune diseases. It is believed that modulation of their activity towards immune activation can be a useful tool in anti-tumor immunotherapeutic strategies. Here we summarize the characteristics of NKT cells and discuss their involvement in immunosurveillance. Furthermore, an update is given about their role and the progress that has been made in the field of multiple myeloma (MM). Finally, some challenges are discussed that are currently hampering further progress.
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Affiliation(s)
- Mérédis Favreau
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
- Laboratory for Molecular Immunology and Inflammation, Department of Rheumatology, Faculty of Medicine and Health Sciences, VIB Inflammation Research Center and Ghent University, Ghent, Belgium
| | - Karin Vanderkerken
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Dirk Elewaut
- Laboratory for Molecular Immunology and Inflammation, Department of Rheumatology, Faculty of Medicine and Health Sciences, VIB Inflammation Research Center and Ghent University, Ghent, Belgium
| | - Koen Venken
- Laboratory for Molecular Immunology and Inflammation, Department of Rheumatology, Faculty of Medicine and Health Sciences, VIB Inflammation Research Center and Ghent University, Ghent, Belgium
| | - Eline Menu
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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104
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Godfrey DI, Uldrich AP, McCluskey J, Rossjohn J, Moody DB. The burgeoning family of unconventional T cells. Nat Immunol 2016; 16:1114-23. [PMID: 26482978 DOI: 10.1038/ni.3298] [Citation(s) in RCA: 540] [Impact Index Per Article: 67.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 09/15/2015] [Indexed: 02/07/2023]
Abstract
While most studies of T lymphocytes have focused on T cells reactive to complexes of peptide and major histocompatibility complex (MHC) proteins, many other types of T cells do not fit this paradigm. These include CD1-restricted T cells, MR1-restricted mucosal associated invariant T cells (MAIT cells), MHC class Ib-reactive T cells, and γδ T cells. Collectively, these T cells are considered 'unconventional', in part because they can recognize lipids, small-molecule metabolites and specially modified peptides. Unlike MHC-reactive T cells, these apparently disparate T cell types generally show simplified patterns of T cell antigen receptor (TCR) expression, rapid effector responses and 'public' antigen specificities. Here we review evidence showing that unconventional T cells are an abundant component of the human immune system and discuss the immunotherapeutic potential of these cells and their antigenic targets.
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Affiliation(s)
- Dale I Godfrey
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia.,Australian Research Council Centre of Excellence for Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - Adam P Uldrich
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia.,Australian Research Council Centre of Excellence for Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - James McCluskey
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program and The Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Australia.,Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, UK.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Australia
| | - D Branch Moody
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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105
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Synthetic glycolipid activators of natural killer T cells as immunotherapeutic agents. Clin Transl Immunology 2016; 5:e69. [PMID: 27195112 PMCID: PMC4855264 DOI: 10.1038/cti.2016.14] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 03/11/2016] [Accepted: 03/13/2016] [Indexed: 12/23/2022] Open
Abstract
Certain types of glycolipids have been found to have remarkable immunomodulatory properties as a result of their ability to activate specific T lymphocyte populations with an extremely wide range of immune effector properties. The most extensively studied glycolipid reactive T cells are known as invariant natural killer T (iNKT) cells. The antigen receptors of these cells specifically recognize certain glycolipids, most notably glycosphingolipids with α-anomeric monosaccharides, presented by the major histocompatibility complex class I-like molecule CD1d. Once activated, iNKT cells can secrete a very diverse array of pro- and anti-inflammatory cytokines to modulate innate and adaptive immune responses. Thus, glycolipid-mediated activation of iNKT cells has been explored for immunotherapy in a variety of disease states, including cancer and a range of infections. In this review, we discuss the design of synthetic glycolipid activators for iNKT cells, their impact on adaptive immune responses and their use to modulate iNKT cell responses to improve immunity against infections and cancer. Current challenges in translating results from preclinical animal studies to humans are also discussed.
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106
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Bandyopadhyay K, Marrero I, Kumar V. NKT cell subsets as key participants in liver physiology and pathology. Cell Mol Immunol 2016; 13:337-46. [PMID: 26972772 PMCID: PMC4856801 DOI: 10.1038/cmi.2015.115] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 12/19/2015] [Accepted: 12/23/2015] [Indexed: 12/17/2022] Open
Abstract
Natural killer T (NKT) cells are innate-like lymphocytes that generally recognize lipid antigens and are enriched in microvascular compartments of the liver. NKT cells can be activated by self- or microbial-lipid antigens and by signaling through toll-like receptors. Following activation, NKT cells rapidly secrete pro-inflammatory or anti-inflammatory cytokines and chemokines, and thereby determine the milieu for subsequent immunity or tolerance. It is becoming clear that two different subsets of NKT cells-type I and type II-have different modes of antigen recognition and have opposing roles in inflammatory liver diseases. Here we focus mainly on the roles of both NKT cell subsets in the maintenance of immune tolerance and inflammatory diseases in liver. Furthermore, how the differential activation of type I and type II NKT cells influences other innate cells and adaptive immune cells to result in important consequences for tissue integrity is discussed. It is crucial that better reagents, including CD1d tetramers, be used in clinical studies to define the roles of NKT cells in liver diseases in patients.
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Affiliation(s)
- Keya Bandyopadhyay
- Department of Medicine, University of California San Diego, La Jolla, CA 92037, USA
| | - Idania Marrero
- Department of Medicine, University of California San Diego, La Jolla, CA 92037, USA
| | - Vipin Kumar
- Department of Medicine, University of California San Diego, La Jolla, CA 92037, USA
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107
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Tard C, Rouxel O, Lehuen A. Regulatory role of natural killer T cells in diabetes. Biomed J 2016; 38:484-95. [PMID: 27013448 PMCID: PMC6138260 DOI: 10.1016/j.bj.2015.04.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 04/24/2015] [Indexed: 01/02/2023] Open
Abstract
Type 1 and type 2 diabetes are growing public health problems. Despite having different pathophysiologies, both diseases are associated with defects in immune regulation. Invariant natural killer T (iNKT) cells are innate-like T cells that recognize glycolipids presented by CD1d. These cells not only play a key role in the defense against pathogens, but also exert potent immunoregulatory functions. The regulatory role of iNKT cells in the prevention of type 1 diabetes has been demonstrated in murine models and analyzed in diabetic patients. The decreased frequency of iNKT cells in non-obese diabetic mice initially suggested the regulatory role of this cell subset. Increasing the frequency or the activation of iNKT cells with agonists protects non-obese diabetic mice from the development of diabetes. Several mechanisms mediate iNKT regulatory functions. They can rapidly produce immunoregulatory cytokines, interleukin (IL)-4 and IL-10. They induce tolerogenic dendritic cells, thereby inducing the anergy of autoreactive anti-islet T cells and increasing the frequency of T regulatory cells (Treg cells). Synthetic agonists are able to activate iNKT cells and represent potential therapeutic treatment in order to prevent type 1 diabetes. Growing evidence points to a role of immune system in glucose intolerance and type 2 diabetes. iNKT cells are resident cells of adipose tissue and their local and systemic frequencies are reduced in obese patients, suggesting their involvement in local and systemic inflammation during obesity. With the discovery of potential continuity between type 1 and type 2 diabetes in some patients, the role of iNKT cells in these diseases deserves further investigation.
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Affiliation(s)
- Celine Tard
- Laboratory "Immunology of Diabetes", U1016 INSERM-Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Laboratoire d'Excellence INFLAMEX, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; DHU Authors, Hôpital Cochin, 75014, Paris, France
| | - Ophelie Rouxel
- Laboratory "Immunology of Diabetes", U1016 INSERM-Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Laboratoire d'Excellence INFLAMEX, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; DHU Authors, Hôpital Cochin, 75014, Paris, France
| | - Agnes Lehuen
- Laboratory "Immunology of Diabetes", U1016 INSERM-Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Laboratoire d'Excellence INFLAMEX, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; DHU Authors, Hôpital Cochin, 75014, Paris, France.
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108
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Smith DG, Williams SJ. Immune sensing of microbial glycolipids and related conjugates by T cells and the pattern recognition receptors MCL and Mincle. Carbohydr Res 2016; 420:32-45. [DOI: 10.1016/j.carres.2015.11.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/24/2015] [Accepted: 11/28/2015] [Indexed: 10/22/2022]
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109
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Dam V, Sikder T, Santosa S. From neutrophils to macrophages: differences in regional adipose tissue depots. Obes Rev 2016; 17:1-17. [PMID: 26667065 DOI: 10.1111/obr.12335] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 09/01/2015] [Accepted: 09/23/2015] [Indexed: 12/27/2022]
Abstract
Currently, we do not fully understand the underlying mechanisms of how regional adiposity promotes metabolic dysregulation. As adipose tissue expands, there is an increase in chronic systemic low-grade inflammation due to greater infiltration of immune cells and production of cytokines. This chronic inflammation is thought to play a major role in the development of metabolic complications and disease such as insulin resistance and diabetes. We know that different adipose tissue depots contribute differently to the risk of metabolic disease. People who have an upper body fat distribution around the abdomen are at greater risk of disease than those who tend to store fat in their lower body around the hips and thighs. Thus, it is conceivable that adipose tissue depots contribute differently to the inflammatory milieu as a result of varied infiltration of immune cell types. In this review, we describe the role and function of major resident immune cells in the development of adipose tissue inflammation and discuss their regional differences in the context of metabolic disease risk. We find that although initial studies have found regional differences, a more comprehensive understanding of how immune cells interrupt adipose tissue homeostasis is needed.
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Affiliation(s)
- V Dam
- Department of Exercise Science, Concordia University, Montreal, QC, Canada.,Nutrition, Obesity, and Metabolism Lab, PERFORM Centre, Concordia University, Montreal, QC, Canada
| | - T Sikder
- Department of Exercise Science, Concordia University, Montreal, QC, Canada.,Nutrition, Obesity, and Metabolism Lab, PERFORM Centre, Concordia University, Montreal, QC, Canada
| | - S Santosa
- Department of Exercise Science, Concordia University, Montreal, QC, Canada.,Nutrition, Obesity, and Metabolism Lab, PERFORM Centre, Concordia University, Montreal, QC, Canada
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110
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Van Rhijn I, Moody DB. Donor Unrestricted T Cells: A Shared Human T Cell Response. THE JOURNAL OF IMMUNOLOGY 2015; 195:1927-32. [PMID: 26297792 DOI: 10.4049/jimmunol.1500943] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The now-famous term "restriction" derived from experiments in which T cells from Donor A failed to recognize Ags presented by cells from Donor B. Restriction results from interdonor variation in MHC genes. Donor restriction dominates immunologists' thinking about the T cell response because it governs organ transplantation and hinders the discovery of disease-associated Ags. However, other T cells can be considered "donor unrestricted" because their targets, CD1a, CD1b, CD1c, CD1d, or MR1, are expressed in a similar form among all humans. A striking feature of donor unrestricted T cells is the expression of invariant TCRs with nearly species-wide distribution. In this article, we review new evidence that donor unrestricted T cells are common in humans. NKT cells, mucosa-associated invariant T cells, and germline-encoded mycolyl-reactive T cells operate outside of the familiar principles of the MHC system, providing a broader picture of T cell function and new opportunities for therapy.
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Affiliation(s)
- Ildiko Van Rhijn
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115; and Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584CL Utrecht, the Netherlands
| | - D Branch Moody
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115; and
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111
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The immunobiology of Campylobacter jejuni: Innate immunity and autoimmune diseases. Immunobiology 2015; 221:535-43. [PMID: 26709064 DOI: 10.1016/j.imbio.2015.12.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 12/05/2015] [Accepted: 12/06/2015] [Indexed: 12/26/2022]
Abstract
The Gram-negative bacterium Campylobacter jejuni causes gastroenteritis and Guillain-Barré syndrome in humans. Recent advances in the immunobiology of C. jejuni have been made. This review summarizes C. jejuni-binding innate receptors and highlights the role of innate immunity in autoimmune diseases. This human pathogen produces a variety of glycoconjugates, including human ganglioside-like determinants and multiple activators of Toll-like receptors (TLRs). Furthermore, C. jejuni targets MyD88, NLRP3 inflammasome, TIR-domain-containing adapter-inducing interferon-β (TRIF), sialic acid-binding immunoglobulin-like lectins (Siglecs), macrophage galactose-type lectin (MGL), and immunoglobulin-like receptors (TREM2, LMIR5/CD300b). The roles of these innate receptors and signaling molecules have been extensively studied. MyD88-mediated TLR activation or inflammasome-dependent IL-1β secretion is essential for autoimmune induction. TRIF mediates the production of type I interferons that promote humoral immune responses and immunoglobulin class-switching. Siglec-1 and Siglec-7 interact directly with gangliosides. Siglec-1 activation enhances phagocytosis and inflammatory responses. MGL internalizes GalNAc-containing glycoconjugates. TREM2 is well-known for its role in phagocytosis. LMIR5 recognizes C. jejuni components and endogenous sulfoglycolipids. Several lines of evidence from animal models of autoimmune diseases suggest that simultaneous activation of innate immunity in the presence of autoreactive lymphocytes or antigen mimicry may link C. jejuni to immunopathology.
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112
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Haeryfar SMM, Mallevaey T. Editorial: CD1- and MR1-Restricted T Cells in Antimicrobial Immunity. Front Immunol 2015; 6:611. [PMID: 26697007 PMCID: PMC4666986 DOI: 10.3389/fimmu.2015.00611] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 11/18/2015] [Indexed: 01/08/2023] Open
Affiliation(s)
- S M Mansour Haeryfar
- Department of Microbiology and Immunology, Western University , London, ON , Canada ; Division of Clinical Immunology and Allergy, Department of Medicine, Western University , London, ON , Canada ; Centre for Human Immunology, Western University , London, ON , Canada ; Lawson Health Research Institute , London, ON , Canada
| | - Thierry Mallevaey
- Department of Immunology, University of Toronto , Toronto, ON , Canada
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113
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Poisson LM, Suhail H, Singh J, Datta I, Denic A, Labuzek K, Hoda MN, Shankar A, Kumar A, Cerghet M, Elias S, Mohney RP, Rodriguez M, Rattan R, Mangalam AK, Giri S. Untargeted Plasma Metabolomics Identifies Endogenous Metabolite with Drug-like Properties in Chronic Animal Model of Multiple Sclerosis. J Biol Chem 2015; 290:30697-712. [PMID: 26546682 DOI: 10.1074/jbc.m115.679068] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Indexed: 12/20/2022] Open
Abstract
We performed untargeted metabolomics in plasma of B6 mice with experimental autoimmune encephalitis (EAE) at the chronic phase of the disease in search of an altered metabolic pathway(s). Of 324 metabolites measured, 100 metabolites that mapped to various pathways (mainly lipids) linked to mitochondrial function, inflammation, and membrane stability were observed to be significantly altered between EAE and control (p < 0.05, false discovery rate <0.10). Bioinformatics analysis revealed six metabolic pathways being impacted and altered in EAE, including α-linolenic acid and linoleic acid metabolism (PUFA). The metabolites of PUFAs, including ω-3 and ω-6 fatty acids, are commonly decreased in mouse models of multiple sclerosis (MS) and in patients with MS. Daily oral administration of resolvin D1, a downstream metabolite of ω-3, decreased disease progression by suppressing autoreactive T cells and inducing an M2 phenotype of monocytes/macrophages and resident brain microglial cells. This study provides a proof of principle for the application of metabolomics to identify an endogenous metabolite(s) possessing drug-like properties, which is assessed for therapy in preclinical mouse models of MS.
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Affiliation(s)
- Laila M Poisson
- From the Center for Bioinformatics and Departments of Public Health Sciences and
| | | | | | - Indrani Datta
- From the Center for Bioinformatics and Departments of Public Health Sciences and
| | | | - Krzysztof Labuzek
- the Department of Pharmacology, Medical University of Silesia, Medyków 18, PL 40-752 Katowice, Poland
| | - Md Nasrul Hoda
- the Department of Neurology, Georgia Health Sciences University, Augusta, Georgia 30912, the Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, Georgia 30912
| | | | - Ashok Kumar
- the Department of Anatomy and Cell Biology, School of Medicine, Wayne State University, Detroit, Michigan 48202
| | | | | | | | - Moses Rodriguez
- the Departments of Neurology and Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota 55906
| | - Ramandeep Rattan
- Division of Gynecology Oncology, Department of Women's Health Services, Henry Ford Health System, Detroit, Michigan 48202
| | - Ashutosh K Mangalam
- the Department of Pathology, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242
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114
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Abstract
The structure and amino acid diversity of the T-cell receptor (TCR), similar in nature to that of Fab portions of antibodies, would suggest that these proteins have a nearly infinite capacity to recognize antigen. Yet all currently defined native T cells expressing an α and β chain in their TCR can only sense antigen when presented in the context of a major histocompatibility complex (MHC) molecule. This MHC molecule can be one of many that exist in vertebrates, presenting small peptide fragments, lipid molecules, or small molecule metabolites. Here we review the pattern of TCR recognition of MHC molecules throughout a broad sampling of species and T-cell lineages and also touch upon T cells that do not appear to require MHC presentation for their surveillance function. We review the diversity of MHC molecules and information on the corresponding T-cell lineages identified in divergent species. We also discuss TCRs with structural domains unlike that of conventional TCRs of mouse and human. By presenting this broad view of TCR sequence, structure, domain organization, and function, we seek to explore how this receptor has evolved across time and been selected for alternative antigen-recognition capabilities in divergent lineages.
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Affiliation(s)
- Caitlin C. Castro
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Committee on Immunology, University of Chicago, Chicago, IL, USA
| | - Adrienne M. Luoma
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Committee on Immunology, University of Chicago, Chicago, IL, USA
| | - Erin J. Adams
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Committee on Immunology, University of Chicago, Chicago, IL, USA
- Committee on Cancer Biology, University of Chicago, Chicago, IL, USA
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115
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Sabatino JJ, Zamvil SS. Unique invariant CD8(+) T cell population persists in MS. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2015; 2:e140. [PMID: 26280013 PMCID: PMC4529280 DOI: 10.1212/nxi.0000000000000140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Joseph J Sabatino
- Department of Neurology (J.J.S.), Johns Hopkins Hospital, Baltimore, MD; and Department of Neurology (S.S.Z.), University of California, San Francisco
| | - Scott S Zamvil
- Department of Neurology (J.J.S.), Johns Hopkins Hospital, Baltimore, MD; and Department of Neurology (S.S.Z.), University of California, San Francisco
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116
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Szabo PA, Anantha RV, Shaler CR, McCormick JK, Haeryfar SMM. CD1d- and MR1-Restricted T Cells in Sepsis. Front Immunol 2015; 6:401. [PMID: 26322041 PMCID: PMC4533011 DOI: 10.3389/fimmu.2015.00401] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/22/2015] [Indexed: 12/23/2022] Open
Abstract
Dysregulated immune responses to infection, such as those encountered in sepsis, can be catastrophic. Sepsis is typically triggered by an overwhelming systemic response to an infectious agent(s) and is associated with high morbidity and mortality even under optimal critical care. Recent studies have implicated unconventional, innate-like T lymphocytes, including CD1d- and MR1-restricted T cells as effectors and/or regulators of inflammatory responses during sepsis. These cell types are typified by invariant natural killer T (iNKT) cells, variant NKT (vNKT) cells, and mucosa-associated invariant T (MAIT) cells. iNKT and vNKT cells are CD1d-restricted, lipid-reactive cells with remarkable immunoregulatory properties. MAIT cells participate in antimicrobial defense, and are restricted by major histocompatibility complex-related protein 1 (MR1), which displays microbe-derived vitamin B metabolites. Importantly, NKT and MAIT cells are rapid and potent producers of immunomodulatory cytokines. Therefore, they may be considered attractive targets during the early hyperinflammatory phase of sepsis when immediate interventions are urgently needed, and also in later phases when adjuvant immunotherapies could potentially reverse the dangerous state of immunosuppression. We will highlight recent findings that point to the significance or the therapeutic potentials of NKT and MAIT cells in sepsis and will also discuss what lies ahead in research in this area.
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Affiliation(s)
- Peter A Szabo
- Department of Microbiology and Immunology, Western University , London, ON , Canada
| | - Ram V Anantha
- Department of Microbiology and Immunology, Western University , London, ON , Canada ; Division of General Surgery, Department of Medicine, Western University , London, ON , Canada
| | - Christopher R Shaler
- Department of Microbiology and Immunology, Western University , London, ON , Canada
| | - John K McCormick
- Department of Microbiology and Immunology, Western University , London, ON , Canada ; Centre for Human Immunology, Western University , London, ON , Canada ; Lawson Health Research Institute , London, ON , Canada
| | - S M Mansour Haeryfar
- Department of Microbiology and Immunology, Western University , London, ON , Canada ; Centre for Human Immunology, Western University , London, ON , Canada ; Lawson Health Research Institute , London, ON , Canada ; Division of Clinical Immunology and Allergy, Department of Medicine, Western University , London, ON , Canada
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117
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Wolf BJ, Tatituri RVV, Almeida CF, Le Nours J, Bhowruth V, Johnson D, Uldrich AP, Hsu FF, Brigl M, Besra GS, Rossjohn J, Godfrey DI, Brenner MB. Identification of a Potent Microbial Lipid Antigen for Diverse NKT Cells. THE JOURNAL OF IMMUNOLOGY 2015; 195:2540-51. [PMID: 26254340 DOI: 10.4049/jimmunol.1501019] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 07/10/2015] [Indexed: 01/17/2023]
Abstract
Semi-invariant/type I NKT cells are a well-characterized CD1d-restricted T cell subset. The availability of potent Ags and tetramers for semi-invariant/type I NKT cells allowed this population to be extensively studied and revealed their central roles in infection, autoimmunity, and tumor immunity. In contrast, diverse/type II NKT (dNKT) cells are poorly understood because the lipid Ags that they recognize are largely unknown. We sought to identify dNKT cell lipid Ag(s) by interrogating a panel of dNKT mouse cell hybridomas with lipid extracts from the pathogen Listeria monocytogenes. We identified Listeria phosphatidylglycerol as a microbial Ag that was significantly more potent than a previously characterized dNKT cell Ag, mammalian phosphatidylglycerol. Further, although mammalian phosphatidylglycerol-loaded CD1d tetramers did not stain dNKT cells, the Listeria-derived phosphatidylglycerol-loaded tetramers did. The structure of Listeria phosphatidylglycerol was distinct from mammalian phosphatidylglycerol because it contained shorter, fully-saturated anteiso fatty acid lipid tails. CD1d-binding lipid-displacement studies revealed that the microbial phosphatidylglycerol Ag binds significantly better to CD1d than do counterparts with the same headgroup. These data reveal a highly potent microbial lipid Ag for a subset of dNKT cells and provide an explanation for its increased Ag potency compared with the mammalian counterpart.
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Affiliation(s)
- Benjamin J Wolf
- Division of Rheumatology, Immunology, and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
| | - Raju V V Tatituri
- Division of Rheumatology, Immunology, and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
| | - Catarina F Almeida
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging at University of Melbourne, Parkville, Victoria 3010, Australia
| | - Jérôme Le Nours
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Veemal Bhowruth
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Darryl Johnson
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging at University of Melbourne, Parkville, Victoria 3010, Australia
| | - Adam P Uldrich
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging at University of Melbourne, Parkville, Victoria 3010, Australia
| | - Fong-Fu Hsu
- Division of Endocrinology, Metabolism, and Lipid Research, Washington University, St. Louis, MO 63110
| | - Manfred Brigl
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115; and
| | - Gurdyal S Besra
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Jamie Rossjohn
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia; Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Dale I Godfrey
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia; Australian Research Council Centre of Excellence in Advanced Molecular Imaging at University of Melbourne, Parkville, Victoria 3010, Australia
| | - Michael B Brenner
- Division of Rheumatology, Immunology, and Allergy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115;
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118
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Dowds CM, Blumberg RS, Zeissig S. Control of intestinal homeostasis through crosstalk between natural killer T cells and the intestinal microbiota. Clin Immunol 2015; 159:128-33. [PMID: 25988859 PMCID: PMC4817350 DOI: 10.1016/j.clim.2015.05.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 05/05/2015] [Accepted: 05/10/2015] [Indexed: 02/08/2023]
Abstract
The human host and the intestinal microbiota co-exist in a mutually beneficial relationship, which contributes to host and microbial metabolism as well as maturation of the host's immune system, among many other pathways (Tremaroli and Backhed, 2012; Hooper et al., 2012). At mucosal surfaces, and particularly in the intestine, the commensal microbiota provides 'colonization resistance' to invading pathogens and maintains homeostasis through microbial regulation of mucosal innate and adaptive immunity (Renz et al., 2012). Recent evidence suggests that natural killer T cells (NKT cells), a subgroup of lipid-reactive T cells, play central roles in bidirectional interactions between the host and the commensal microbiota, which govern intestinal homeostasis and prevent inflammation. Here, we provide a brief overview of recently identified pathways of commensal microbial regulation of NKT cells, discuss feedback mechanisms of NKT cell-dependent control of microbial colonization and composition, and highlight the critical role of host-microbial cross-talk for prevention of NKT cell-dependent mucosal inflammation.
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Affiliation(s)
- C Marie Dowds
- Department of Internal Medicine I, University Medical Center Schleswig-Holstein, Kiel, Germany
| | - Richard S Blumberg
- Division of Gastroenterology, Hepatology, and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Sebastian Zeissig
- Department of Internal Medicine I, University Medical Center Schleswig-Holstein, Kiel, Germany; Department of Medicine I, University Medical Center Dresden, Technical University Dresden, Dresden, Germany; Center for Regenerative Therapies Dresden (CRTD), Technical University Dresden, Dresden, Germany.
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119
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Macho-Fernandez E, Brigl M. The Extended Family of CD1d-Restricted NKT Cells: Sifting through a Mixed Bag of TCRs, Antigens, and Functions. Front Immunol 2015; 6:362. [PMID: 26284062 PMCID: PMC4517383 DOI: 10.3389/fimmu.2015.00362] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 07/04/2015] [Indexed: 01/21/2023] Open
Abstract
Natural killer T (NKT) cells comprise a family of specialized T cells that recognize lipid antigens presented by CD1d. Based on their T cell receptor (TCR) usage and antigen specificities, CD1d-restricted NKT cells have been divided into two main subsets: type I NKT cells that use a canonical invariant TCR α-chain and recognize α-galactosylceramide (α-GalCer), and type II NKT cells that use a more diverse αβ TCR repertoire and do not recognize α-GalCer. In addition, α-GalCer-reactive NKT cells that use non-canonical αβ TCRs and CD1d-restricted T cells that use γδ or δ/αβ TCRs have recently been identified, revealing further diversity among CD1d-restricted T cells. Importantly, in addition to their distinct antigen specificities, functional differences are beginning to emerge between the different members of the CD1d-restricted T cell family. In this review, while using type I NKT cells as comparison, we will focus on type II NKT cells and the other non-invariant CD1d-restricted T cell subsets, and discuss our current understanding of the antigens they recognize, the formation of stimulatory CD1d/antigen complexes, the modes of TCR-mediated antigen recognition, and the mechanisms and consequences of their activation that underlie their function in antimicrobial responses, anti-tumor immunity, and autoimmunity.
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Affiliation(s)
- Elodie Macho-Fernandez
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Manfred Brigl
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
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120
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Delovitch TL. Imaging of NKT Cell Recirculation and Tissue Migration during Antimicrobial Immunity. Front Immunol 2015; 6:356. [PMID: 26236312 PMCID: PMC4500992 DOI: 10.3389/fimmu.2015.00356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 06/30/2015] [Indexed: 01/09/2023] Open
Affiliation(s)
- Terry L. Delovitch
- Laboratory of Autoimmune Diabetes, Department of Microbiology and Immunology, Robarts Research Institute, Western University, London, ON, Canada
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121
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Vincent IS, Okusa MD. Adenosine 2A receptors in acute kidney injury. Acta Physiol (Oxf) 2015; 214:303-10. [PMID: 25877257 DOI: 10.1111/apha.12508] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 10/14/2014] [Accepted: 04/12/2015] [Indexed: 12/23/2022]
Abstract
Acute kidney injury (AKI) is an important clinical problem that may lead to death and for those who survive, the sequelae of AKI include loss of quality of life, chronic kidney disease and end-stage renal disease. The incidence of AKI continues to rise without clear successes in humans for the pharmacological prevention of AKI or treatment of established AKI. Dendritic cells and macrophages are critical early initiators of innate immunity in the kidney and orchestrate inflammation subsequent to ischaemia-reperfusion injury. These innate cells are the most abundant leucocytes present in the kidney, and they represent a heterogeneous population of cells that are capable of responding to cues from the microenvironment derived from pathogens or endogenous inflammatory mediators such as cytokines or anti-inflammatory mediators such as adenosine. Lymphocyte subsets such as natural killer T cells and Tregs also play roles in regulating ischaemic injury by promoting and suppressing inflammation respectively. Adenosine, produced in response to IR, is generally considered as a protective signalling molecule and elicits its physiological responses through four distinct adenosine receptors. However, its short half-life, lack of specificity and rapid metabolism limit the use of adenosine as a therapeutic agent. These adenosine receptors play various roles in regulating the activity of the aforementioned hematopoietic cells in elevated levels of adenosine such as during hypoxia. This review focuses on the importance of one receptor, the adenosine 2A subtype, in blocking inflammation associated with AKI.
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Affiliation(s)
- I. S. Vincent
- Division of Nephrology and Center for Immunity; Inflammation and Regenerative Medicine; University of Virginia Health System; Charlottesville VA USA
| | - M. D. Okusa
- Division of Nephrology and Center for Immunity; Inflammation and Regenerative Medicine; University of Virginia Health System; Charlottesville VA USA
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122
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Van Kaer L, Wu L, Parekh VV. Natural killer T cells in multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis. Immunology 2015; 146:1-10. [PMID: 26032048 DOI: 10.1111/imm.12485] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 05/18/2015] [Accepted: 05/27/2015] [Indexed: 12/30/2022] Open
Abstract
Multiple sclerosis (MS) is a chronic inflammatory disease that causes demyelination of neurons in the central nervous system. Traditional therapies for MS have involved anti-inflammatory and immunosuppressive drugs with significant side effects that often only provide short-term relief. A more desirable outcome of immunotherapy would be to protect against disease before its clinical manifestation or to halt disease after its initiation. One attractive approach to accomplish this goal would be to restore tolerance by targeting immunoregulatory cell networks. Although much of the work in this area has focused on CD4(+) Foxp3(+) regulatory T cells, other studies have investigated natural killer T (NKT) cells, a subset of T cells that recognizes glycolipid antigens in the context of the CD1d glycoprotein. Studies with human MS patients have revealed alterations in the numbers and functions of NKT cells, which have been partially supported by studies with the experimental autoimmune encephalomyelitis model of MS. Additional studies have shown that activation of NKT cells with synthetic lipid antigens can, at least under certain experimental conditions, protect mice against the development of MS-like disease. Although mechanisms of this protection remain to be fully investigated, current evidence suggests that it involves interactions with other immunoregulatory cell types such as regulatory T cells and immunosuppressive myeloid cells. These studies have provided a strong foundation for the rational design of NKT-cell-based immunotherapies for MS that induce tolerance while sparing overall immune function. Nevertheless, additional pre-clinical and clinical studies will be required to bring this goal to fruition.
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Affiliation(s)
- Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Vrajesh V Parekh
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
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123
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Marrero I, Ware R, Kumar V. Type II NKT Cells in Inflammation, Autoimmunity, Microbial Immunity, and Cancer. Front Immunol 2015; 6:316. [PMID: 26136748 PMCID: PMC4470258 DOI: 10.3389/fimmu.2015.00316] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 06/02/2015] [Indexed: 12/12/2022] Open
Abstract
Natural killer T cells (NKT) recognize self and microbial lipid antigens presented by non-polymorphic CD1d molecules. Two major NKT cell subsets, type I and II, express different types of antigen receptors (TCR) with distinct mode of CD1d/lipid recognition. Though type II NKT cells are less frequent in mice and difficult to study, they are predominant in human. One of the major subsets of type II NKT cells reactive to the self-glycolipid sulfatide is the best characterized and has been shown to induce a dominant immune regulatory mechanism that controls inflammation in autoimmunity and in anti-cancer immunity. Recently, type II NKT cells reactive to other self-glycolipids and phospholipids have been identified suggesting both promiscuous and specific TCR recognition in microbial immunity as well. Since the CD1d pathway is highly conserved, a detailed understanding of the biology and function of type II NKT cells as well as their interplay with type I NKT cells or other innate and adaptive T cells will have major implications for potential novel interventions in inflammatory and autoimmune diseases, microbial immunity, and cancer.
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Affiliation(s)
- Idania Marrero
- Laboratory of Immune Regulation, Department of Medicine, University of California San Diego , La Jolla, CA , USA
| | - Randle Ware
- Laboratory of Immune Regulation, Department of Medicine, University of California San Diego , La Jolla, CA , USA
| | - Vipin Kumar
- Laboratory of Immune Regulation, Department of Medicine, University of California San Diego , La Jolla, CA , USA
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124
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Abstract
Type 1 and type 2 diabetes are growing public health problems. Despite having different pathophysiologies, both diseases are associated with defects in immune regulation. Invariant natural killer T (iNKT) cells are innate-like T cells that recognize glycolipids presented by CD1d. These cells not only play a key role in the defense against pathogens, but also exert potent immunoregulatory functions. The regulatory role of iNKT cells in the prevention of type 1 diabetes has been demonstrated in murine models and analyzed in diabetic patients. The decreased frequency of iNKT cells in non-obese diabetic mice initially suggested the regulatory role of this cell subset. Increasing the frequency or the activation of iNKT cells with agonists protects non-obese diabetic mice from the development of diabetes. Several mechanisms mediate iNKT regulatory functions. They can rapidly produce immunoregulatory cytokines, interleukin (IL)-4 and IL-10. They induce tolerogenic dendritic cells, thereby inducing the anergy of autoreactive anti-islet T cells and increasing the frequency of T regulatory cells (Treg cells). Synthetic agonists are able to activate iNKT cells and represent potential therapeutic treatment in order to prevent type 1 diabetes. Growing evidence points to a role of immune system in glucose intolerance and type 2 diabetes. iNKT cells are resident cells of adipose tissue and their local and systemic frequencies are reduced in obese patients, suggesting their involvement in local and systemic inflammation during obesity. With the discovery of potential continuity between type 1 and type 2 diabetes in some patients, the role of iNKT cells in these diseases deserves further investigation.
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Affiliation(s)
| | | | - Agnes Lehuen
- Laboratory "Immunology of Diabetes" U1016 INSERM Institut Cochin; CNRS UMR8104; Laboratoire d'Excellence INFLAMEX, Université Paris Descartes, Sorbonne Paris Cité; DHU Authors, Hôpital Cochin, 75014, Paris, France
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125
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Slauenwhite D, Johnston B. Regulation of NKT Cell Localization in Homeostasis and Infection. Front Immunol 2015; 6:255. [PMID: 26074921 PMCID: PMC4445310 DOI: 10.3389/fimmu.2015.00255] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 05/07/2015] [Indexed: 01/23/2023] Open
Abstract
Natural killer T (NKT) cells are a specialized subset of T lymphocytes that regulate immune responses in the context of autoimmunity, cancer, and microbial infection. Lipid antigens derived from bacteria, parasites, and fungi can be presented by CD1d molecules and recognized by the canonical T cell receptors on NKT cells. Alternatively, NKT cells can be activated through recognition of self-lipids and/or pro-inflammatory cytokines generated during infection. Unlike conventional T cells, only a small subset of NKT cells traffic through the lymph nodes under homeostatic conditions, with the largest NKT cell populations localizing to the liver, lungs, spleen, and bone marrow. This is thought to be mediated by differences in chemokine receptor expression profiles. However, the impact of infection on the tissue localization and function of NKT remains largely unstudied. This review focuses on the mechanisms mediating the establishment of peripheral NKT cell populations during homeostasis and how tissue localization of NKT cells is affected during infection.
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Affiliation(s)
- Drew Slauenwhite
- Department of Microbiology and Immunology, Dalhousie University , Halifax, NS , Canada
| | - Brent Johnston
- Department of Microbiology and Immunology, Dalhousie University , Halifax, NS , Canada ; Department of Pediatrics, Dalhousie University , Halifax, NS , Canada ; Department of Pathology, Dalhousie University , Halifax, NS , Canada ; Beatrice Hunter Cancer Research Institute , Halifax, NS , Canada
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126
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Evidence for TLR4 and FcRγ-CARD9 activation by cholera toxin B subunit and its direct bindings to TREM2 and LMIR5 receptors. Mol Immunol 2015; 66:463-71. [PMID: 26021803 DOI: 10.1016/j.molimm.2015.05.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Revised: 04/08/2015] [Accepted: 05/10/2015] [Indexed: 11/23/2022]
Abstract
Cholera toxin (CTX) is a virulent factor of Vibrio cholerae that causes life-threatening diarrheal disease. Its non-toxic subunit CTB has been extensively studied for vaccine delivery. In immune cells, CTB induces a number of signaling molecules related to cellular activation and cytokine production. The mechanisms by which CTB exerts its immunological effects are not understood. We report here the immunological targets of CTB. The unexpected finding that GM1 ganglioside inhibited NF-κB activation in human monocytes stimulated with CTX and agonists of Toll-like receptors (TLR) suggests the possibility of CTX-TLR interaction. Indeed, CTX-induced IL-6 production was substantially reduced in MyD88(-/-) or TLR4(-/-) macrophages. Ectopic expression of TLR4 was required for CTX-induced NF-κB activation in HEK 293 cells. Furthermore, the inflammatory capacity of CTB was lost in the absence of TLR4, adaptor protein FcRγ, or its downstream signaling molecule CARD9. Attempts have been made to identify CTB-binding targets from various C-type lectin and immunoglobulin-like receptors. CTB targeted not only GM1 and TLR4 but also TREM2 and LMIR5/CD300b. CTB-TREM2 interaction initiated signal transduction through adaptor protein DAP12. The binding of CTB inhibited LMIR5 activation induced by its endogenous ligand 3-O-sulfo-β-d-galactosylceramide C24:1. In summary, CTB targets TLR4, FcRγ-CARD9, TREM2, and LMIR5. These findings provide new insights into the immunobiology of cholera toxin.
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127
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Liew PX, Kubes P. Intravital imaging - dynamic insights into natural killer T cell biology. Front Immunol 2015; 6:240. [PMID: 26042123 PMCID: PMC4438604 DOI: 10.3389/fimmu.2015.00240] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 05/05/2015] [Indexed: 12/22/2022] Open
Abstract
Natural killer T (NKT) cells were first recognized more than two decades ago as a separate and distinct lymphocyte lineage that modulates an expansive range of immune responses. As innate immune cells, NKT cells are activated early during inflammation and infection, and can subsequently stimulate or suppress the ensuing immune response. As a result, researchers hope to harness the immunomodulatory properties of NKT cells to treat a variety of diseases. However, many questions still remain unanswered regarding the biology of NKT cells, including how these cells traffic from the thymus to peripheral organs and how they play such contrasting roles in different immune responses and diseases. In this new era of intravital fluorescence microscopy, we are now able to employ this powerful tool to provide quantitative and dynamic insights into NKT cell biology including cellular dynamics, patrolling, and immunoregulatory functions with exquisite resolution. This review will highlight and discuss recent studies that use intravital imaging to understand the spectrum of NKT cell behavior in a variety of animal models.
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Affiliation(s)
- Pei Xiong Liew
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary , Calgary, AB , Canada
| | - Paul Kubes
- Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary , Calgary, AB , Canada
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128
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Abstract
The immune system can be divided into innate and adaptive components that differ in their rate and mode of cellular activation, with innate immune cells being the first responders to invading pathogens. Recent advances in the identification and characterization of innate lymphoid cells have revealed reiterative developmental programs that result in cells with effector fates that parallel those of adaptive lymphoid cells and are tailored to effectively eliminate a broad spectrum of pathogenic challenges. However, activation of these cells can also be associated with pathologies such as autoimmune disease. One major distinction between innate and adaptive immune system cells is the constitutive expression of ID proteins in the former and inducible expression in the latter. ID proteins function as antagonists of the E protein transcription factors that play critical roles in lymphoid specification as well as B- and T-lymphocyte development. In this review, we examine the transcriptional mechanisms controlling the development of innate lymphocytes, including natural killer cells and the recently identified innate lymphoid cells (ILC1, ILC2, and ILC3), and innate-like lymphocytes, including natural killer T cells, with an emphasis on the known requirements for the ID proteins.
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Affiliation(s)
- Mihalis Verykokakis
- Committee on Immunology and Department of Pathology, The University of Chicago, Chicago, IL, USA
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129
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Birkholz AM, Howell AR, Kronenberg M. The Alpha and Omega of Galactosylceramides in T Cell Immune Function. J Biol Chem 2015; 290:15365-15370. [PMID: 25947378 DOI: 10.1074/jbc.r115.647057] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glycosphingolipids are a subgroup of glycolipids that contain an amino alcohol sphingoid base linked to sugars. They are found in the membranes of cells ranging from bacteria to vertebrates. This group of lipids is known to stimulate the immune system through activation of a type of white blood cell known as natural killer T cell (NKT cell). Here we summarize the extensive research that has been done to identify the structures of natural glycolipids that stimulate NKT cells and to determine how these antigens are recognized. We also review studies designed to understand how glycolipid variants, both natural and synthetic, can alter the responses of NKT cells, leading to dramatic changes in the global immune response.
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Affiliation(s)
- Alysia M Birkholz
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, California 92037; Division of Biological Sciences, University of California, San Diego, La Jolla, California 92037
| | - Amy R Howell
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269
| | - Mitchell Kronenberg
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, California 92037; Division of Biological Sciences, University of California, San Diego, La Jolla, California 92037.
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130
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Maricic I, Sheng H, Marrero I, Seki E, Kisseleva T, Chaturvedi S, Molle N, Mathews KS, Gao B, Kumar V. Inhibition of type I natural killer T cells by retinoids or following sulfatide-mediated activation of type II natural killer T cells attenuates alcoholic liver disease in mice. Hepatology 2015; 61:1357-69. [PMID: 25477000 PMCID: PMC4376634 DOI: 10.1002/hep.27632] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 11/26/2014] [Indexed: 02/01/2023]
Abstract
UNLABELLED Innate immune mechanisms leading to liver injury subsequent to chronic alcohol ingestion are poorly understood. Natural killer T (NKT) cells, enriched in the liver and comprised of at least two distinct subsets, type I and II, recognize different lipid antigens presented by CD1d molecules. We have investigated whether differential activation of NKT cell subsets orchestrates inflammatory events leading to alcoholic liver disease (ALD). We found that after chronic plus binge feeding of Lieber-DeCarli liquid diet in male C57BL/6 mice, type I, but not type II, NKT cells are activated, leading to recruitment of inflammatory Gr-1(high) CD11b(+) cells into the liver. A central finding is that liver injury after alcohol feeding is dependent upon type I NKT cells. Thus, liver injury is significantly inhibited in Jα18(-/-) mice deficient in type I NKT cells as well as after their inactivation by sulfatide-mediated activation of type II NKT cells. Furthermore, we have identified a novel pathway involving all-trans retinoic acid (ATRA) and its receptor (RARγ) signaling that inhibits type I NKT cells and, consequently, ALD. A semiquantitative polymerase chain reaction analysis of hepatic gene expression of some of the key proinflammatory molecules shared in human disease indicated that their up-regulation in ALD is dependent upon type I NKT cells. CONCLUSIONS Type I, but not type II, NKT cells become activated after alcohol feeding. Type I NKT cell-induced inflammation and neutrophil recruitment results in liver tissue damage whereas type II NKT cells protect from injury in ALD. Inhibition of type I NKT cells by retinoids or by sulfatide prevents ALD. Given that the CD1d pathway is highly conserved between mice and humans, NKT cell subsets might be targeted for potential therapeutic intervention in ALD.
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Affiliation(s)
- Igor Maricic
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121, USA
| | - Huiming Sheng
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121, USA
| | - Idania Marrero
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121, USA
| | - Ehikiro Seki
- Division of Gastroenterology, Department of Medicine, UCSD, La Jolla, CA 92037, USA
| | - Tatiana Kisseleva
- Division of Gastroenterology, Department of Medicine, UCSD, La Jolla, CA 92037, USA
| | - Som Chaturvedi
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121, USA
| | - Natasha Molle
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121, USA
| | | | - Bin Gao
- NIH, Bathesda, MD 20892, USA
| | - Vipin Kumar
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121, USA
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131
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Rampuria P, Lang ML. CD1d-dependent expansion of NKT follicular helper cells in vivo and in vitro is a product of cellular proliferation and differentiation. Int Immunol 2015; 27:253-63. [PMID: 25710490 DOI: 10.1093/intimm/dxv007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 02/16/2015] [Indexed: 12/16/2022] Open
Abstract
NKT follicular helper cells (NKTfh cells) are a recently discovered functional subset of CD1d-restricted NKT cells. Given the potential for NKTfh cells to promote specific antibody responses and germinal center reactions, there is much interest in determining the conditions under which NKTfh cells proliferate and/or differentiate in vivo and in vitro. We confirm that NKTfh cells expressing the canonical semi-invariant Vα14 TCR were CXCR5(+)/ICOS(+)/PD-1(+)/Bcl6(+) and increased in number following administration of the CD1d-binding glycolipid α-galactosylceramide (α-GC) to C57Bl/6 mice. We show that the α-GC-stimulated increase in NKTfh cells was CD1d-dependent since the effect was diminished by reduced CD1d expression. In vivo and in vitro treatment with α-GC, singly or in combination with IL-2, showed that NKTfh cells increased in number to a greater extent than total NKT cells, but proliferation was near-identical in both populations. Acquisition of the NKTfh phenotype from an adoptively transferred PD-1-depleted cell population was also evident, showing that peripheral NKT cells differentiated into NKTfh cells. Therefore, the α-GC-stimulated, CD1d-dependent increase in peripheral NKTfh cells is a result of cellular proliferation and differentiation. These findings advance our understanding of the immune response following immunization with CD1d-binding glycolipids.
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Affiliation(s)
- Pragya Rampuria
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Mark L Lang
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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132
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Carreño LJ, Kharkwal SS, Porcelli SA. Optimizing NKT cell ligands as vaccine adjuvants. Immunotherapy 2015; 6:309-20. [PMID: 24762075 DOI: 10.2217/imt.13.175] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
NKT cells are a subpopulation of T lymphocytes with phenotypic properties of both T and NK cells and a wide range of immune effector properties. In particular, one subset of these cells, known as invariant NKT cells (iNKT cells), has attracted substantial attention because of their ability to be specifically activated by glycolipid antigens presented by a cell surface protein called CD1d. The development of synthetic α-galactosylceramides as a family of powerful glycolipid agonists for iNKT cells has led to approaches for augmenting a wide variety of immune responses, including those involved in vaccination against infections and cancers. Here, we review basic, preclinical and clinical observations supporting approaches to improving immune responses through the use of iNKT cell-activating glycolipids. Results from preclinical animal studies and preliminary clinical studies in humans identify many promising applications for this approach in the development of vaccines and novel immunotherapies.
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Affiliation(s)
- Leandro J Carreño
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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133
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Organ-specific protective role of NKT cells in virus-induced inflammatory demyelination and myocarditis depends on mouse strain. J Neuroimmunol 2015; 278:174-84. [PMID: 25434008 DOI: 10.1016/j.jneuroim.2014.11.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/14/2014] [Accepted: 11/03/2014] [Indexed: 02/08/2023]
Abstract
Theiler's murine encephalomyelitis virus (TMEV) can induce demyelination or myocarditis in susceptible mouse strains. A deficiency of NKT cells exacerbated TMEV-induced demyelinating disease (TMEV-IDD) in SJL/J and BALB/c mice. In C57BL/6 background, however, NKT-cell-deficient Jα18 KO mice remained as resistant to TMEV-IDD as wild-type mice. Echocardiography and histology showed that Jα18 KO mice developed more severe myocarditis (greater T cell infiltration and fibrosis) than wild-type mice, suggesting a protective role of NKT cells in myocarditis in C57BL/6 mice. Jα18 KO mice had higher cardiac viral RNA and anti-viral antibody titers, but had lower lymphoproliferation and IL-4 and IL-10 production.
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135
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Immunity at the Maternal–Fetal Interface. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00114-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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136
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Abstract
Chronic inflammation including B-cell activation is commonly observed in both inherited (Gaucher disease [GD]) and acquired disorders of lipid metabolism. However, the cellular mechanisms underlying B-cell activation in these settings remain to be elucidated. Here, we report that β-glucosylceramide 22:0 (βGL1-22) and glucosylsphingosine (LGL1), 2 major sphingolipids accumulated in GD, can be recognized by a distinct subset of CD1d-restricted human and murine type II natural killer T (NKT) cells. Human βGL1-22- and LGL1-reactive CD1d tetramer-positive T cells have a distinct T-cell receptor usage and genomic and cytokine profiles compared with the classical type I NKT cells. In contrast to type I NKT cells, βGL1-22- and LGL1-specific NKT cells constitutively express T-follicular helper (TFH) phenotype. Injection of these lipids leads to an increase in respective lipid-specific type II NKT cells in vivo and downstream induction of germinal center B cells, hypergammaglobulinemia, and production of antilipid antibodies. Human βGL1-22- and LGL1-specific NKT cells can provide efficient cognate help to B cells in vitro. Frequency of LGL1-specific T cells in GD mouse models and patients correlates with disease activity and therapeutic response. Our studies identify a novel type II NKT-mediated pathway for glucosphingolipid-mediated dysregulation of humoral immunity and increased risk of B-cell malignancy observed in metabolic lipid disorders.
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137
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Ivanova MV, Tukhvatulin AI, Dzharullaeva AS, Logunov DY, Zakharova MN. Myelin lipids in the development of the autoimmune response in multiple sclerosis. NEUROCHEM J+ 2014. [DOI: 10.1134/s1819712414040035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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138
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Fuss IJ, Joshi B, Yang Z, Degheidy H, Fichtner-Feigl S, de Souza H, Rieder F, Scaldaferri F, Schirbel A, Scarpa M, West G, Yi C, Xu L, Leland P, Yao M, Mannon P, Puri RK, Fiocchi C, Strober W. IL-13Rα2-bearing, type II NKT cells reactive to sulfatide self-antigen populate the mucosa of ulcerative colitis. Gut 2014; 63:1728-36. [PMID: 24515806 PMCID: PMC4782805 DOI: 10.1136/gutjnl-2013-305671] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
OBJECTIVE Previous studies have shown that ulcerative colitis (UC) is associated with the presence of lamina propria non-invariant (Type II) NKT cells producing IL-13 and mediating epithelial cell cytotoxicity. Here we sought to define the antigen(s) stimulating the NKT cells and to quantitate these cells in the UC lamina propria. DESIGN Detection of Type II NKT cells in UC lamina propria mononuclear cells (LPMC) with lyso-sulfatide loaded tetramer and quantum dot-based flow cytometry and staining. Culture of UC LPMCs with lyso-sulfatide glycolipid to determine sulfatide induction of epithelial cell cytotoxicity, IL-13 production and IL-13Rα2 expression. Blinded quantum dot-based phenotypic analysis to assess UC LPMC expression of IL-13Rα2, CD161 and IL-13. RESULTS Approximately 36% of UC LPMC were lyso-sulfatide tetramer positive, whereas few, if any, control LPMCs were positive. When tested, the positive cells were also CD3 and IL-13Rα2 positive. Culture of UC LPMC with lyso-sulfatide glycolipid showed that sulfatide stimulates UC LPMC production of IL-13 and induces UC CD161 LPMC-mediated cytotoxicity of activated epithelial cells; additionally, lyso-sulfatide induces enhanced expression of IL-13Rα2. Finally, blinded phenotypic analysis of UC LP MC using multicolour quantum dot-staining technology showed that approximately 60% of the LPMC bear both IL-13Rα2 and CD161 and most of these cells also produce IL-13. CONCLUSIONS These studies show that UC lamina propria is replete with Type II NKT cells responsive to lyso-sulfatide glycolipid and bearing IL-13Rα2. Since lyso-sulfatide is a self-antigen, these data suggest that an autoimmune response is involved in UC pathogenesis.
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Affiliation(s)
- Ivan J. Fuss
- Mucosal Immunity Section, Laboratory of Host Defenses, NIAID NIH, Bethesda Maryland, USA, 20892
| | - Bharat Joshi
- Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research FDA, Bethesda Maryland, USA, 20892
| | - Zhiqiong Yang
- Mucosal Immunity Section, Laboratory of Host Defenses, NIAID NIH, Bethesda Maryland, USA, 20892
| | - Heba Degheidy
- Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research FDA, Bethesda Maryland, USA, 20892
| | | | - Heitor de Souza
- Department of Pathobiology, The Cleveland Clinic Foundation, Cleveland Ohio, USA, 44195
| | - Florian Rieder
- Department of Pathobiology, The Cleveland Clinic Foundation, Cleveland Ohio, USA, 44195
| | - Franco Scaldaferri
- Department of Pathobiology, The Cleveland Clinic Foundation, Cleveland Ohio, USA, 44195
| | - Anja Schirbel
- Department of Pathobiology, The Cleveland Clinic Foundation, Cleveland Ohio, USA, 44195
| | - Melania Scarpa
- Department of Pathobiology, The Cleveland Clinic Foundation, Cleveland Ohio, USA, 44195
| | - Gail West
- Department of Pathobiology, The Cleveland Clinic Foundation, Cleveland Ohio, USA, 44195
| | - Chuli Yi
- Mucosal Immunity Section, Laboratory of Host Defenses, NIAID NIH, Bethesda Maryland, USA, 20892
| | - Lili Xu
- Mucosal Immunity Section, Laboratory of Host Defenses, NIAID NIH, Bethesda Maryland, USA, 20892
| | - Pamela Leland
- Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research FDA, Bethesda Maryland, USA, 20892
| | - Michael Yao
- Mucosal Immunity Section, Laboratory of Host Defenses, NIAID NIH, Bethesda Maryland, USA, 20892
| | - Peter Mannon
- Mucosal Immunity Section, Laboratory of Host Defenses, NIAID NIH, Bethesda Maryland, USA, 20892
| | - Raj K. Puri
- Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research FDA, Bethesda Maryland, USA, 20892
| | - Claudio Fiocchi
- Department of Pathobiology, The Cleveland Clinic Foundation, Cleveland Ohio, USA, 44195
| | - Warren Strober
- Mucosal Immunity Section, Laboratory of Host Defenses, NIAID NIH, Bethesda Maryland, USA, 20892
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139
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Weng X, Liao CM, Bagchi S, Cardell SL, Stein PL, Wang CR. The adaptor protein SAP regulates type II NKT-cell development, cytokine production, and cytotoxicity against lymphoma. Eur J Immunol 2014; 44:3646-57. [PMID: 25236978 DOI: 10.1002/eji.201444848] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/19/2014] [Accepted: 09/16/2014] [Indexed: 11/09/2022]
Abstract
CD1d-restricted NKT cells represent a unique lineage of immunoregulatory T cells that are divided into two groups, type I and type II, based on their TCR usage. Because there are no specific tools to identify type II NKT cells, little is known about their developmental requirements and functional regulation. In our previous study, we showed that signaling lymphocytic activation molecule associated protein (SAP) is essential for the development of type II NKT cells. Here, using a type II NKT-cell TCR transgenic mouse model, we demonstrated that CD1d-expressing hematopoietic cells, but not thymic epithelial cells, meditate efficient selection of type II NKT cells. Furthermore, we showed that SAP regulates type II NKT-cell development by controlling early growth response 2 protein and promyelocytic leukemia zinc finger expression. SAP-deficient 24αβ transgenic T cells (24αβ T cells) exhibited an immature phenotype with reduced Th2 cytokine-producing capacity and diminished cytotoxicity to CD1d-expressing lymphoma cells. The impaired IL-4 production by SAP-deficient 24αβ T cells was associated with reduced IFN regulatory factor 4 and GATA-3 induction following TCR stimulation. Collectively, these data suggest that SAP is critical for regulating type II NKT cell responses. Aberrant responses of these T cells may contribute to the immune dysregulation observed in X-linked lymphoproliferative disease caused by mutations in SAP.
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Affiliation(s)
- Xiufang Weng
- Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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140
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Kumar V, Delovitch TL. Different subsets of natural killer T cells may vary in their roles in health and disease. Immunology 2014; 142:321-36. [PMID: 24428389 DOI: 10.1111/imm.12247] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 01/08/2014] [Accepted: 01/08/2014] [Indexed: 12/31/2022] Open
Abstract
Natural killer T cells (NKT) can regulate innate and adaptive immune responses. Type I and type II NKT cell subsets recognize different lipid antigens presented by CD1d, an MHC class-I-like molecule. Most type I NKT cells express a semi-invariant T-cell receptor (TCR), but a major subset of type II NKT cells reactive to a self antigen sulphatide use an oligoclonal TCR. Whereas TCR-α dominates CD1d-lipid recognition by type I NKT cells, TCR-α and TCR-β contribute equally to CD1d-lipid recognition by type II NKT cells. These variable modes of NKT cell recognition of lipid-CD1d complexes activate a host of cytokine-dependent responses that can either exacerbate or protect from disease. Recent studies of chronic inflammatory and autoimmune diseases have led to a hypothesis that: (i) although type I NKT cells can promote pathogenic and regulatory responses, they are more frequently pathogenic, and (ii) type II NKT cells are predominantly inhibitory and protective from such responses and diseases. This review focuses on a further test of this hypothesis by the use of recently developed techniques, intravital imaging and mass cytometry, to analyse the molecular and cellular dynamics of type I and type II NKT cell antigen-presenting cell motility, interaction, activation and immunoregulation that promote immune responses leading to health versus disease outcomes.
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Affiliation(s)
- Vipin Kumar
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA, USA
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141
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Maricic I, Girardi E, Zajonc DM, Kumar V. Recognition of lysophosphatidylcholine by type II NKT cells and protection from an inflammatory liver disease. THE JOURNAL OF IMMUNOLOGY 2014; 193:4580-9. [PMID: 25261475 DOI: 10.4049/jimmunol.1400699] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Lipids presented by the MHC class I-like molecule, CD1d, are recognized by NK T (NKT) cells, which can be broadly categorized into two subsets. The well-characterized type I NKT cells express a semi-invariant TCR and can recognize both α- and β-linked glycolipids, whereas type II NKT cells are less well studied, express a relatively diverse TCR repertoire, and recognize β-linked lipids. Recent structural studies have shown a distinct mode of recognition of a self-glycolipid sulfatide bound to CD1d by a type II NKT TCR. To further characterize Ag recognition by these cells, we have used the structural data and screened other small molecules able to bind to CD1d and activate type II NKT cells. Using plate-bound CD1d and APC-based Ag presentation assay, we found that phospholipids such as lysophosphatidylcholine (LPC) can stimulate the sulfatide-reactive type II NKT hybridoma Hy19.3 in a CD1d-dependent manner. Using plasmon resonance studies, we found that this type II NKT TCR binds with CD1d-bound LPC with micromolar affinities similar to that for sulfatide. Furthermore, LPC-mediated activation of type II NKT cells leads to anergy induction in type I NKT cells and affords protection from Con A-induced hepatitis. These data indicate that, in addition to self-glycolipids, self-lysophospholipids are also recognized by type II NKT cells. Because lysophospholipids are involved during inflammation, our findings have implications for not only understanding activation of type II NKT cells in physiological settings, but also for the development of immune intervention in inflammatory diseases.
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Affiliation(s)
- Igor Maricic
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| | - Enrico Girardi
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Dirk M Zajonc
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Vipin Kumar
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
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142
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Mayo L, Trauger SA, Blain M, Nadeau M, Patel B, Alvarez JI, Mascanfroni ID, Yeste A, Kivisäkk P, Kallas K, Ellezam B, Bakshi R, Prat A, Antel JP, Weiner HL, Quintana FJ. Regulation of astrocyte activation by glycolipids drives chronic CNS inflammation. Nat Med 2014; 20:1147-56. [PMID: 25216636 DOI: 10.1038/nm.3681] [Citation(s) in RCA: 330] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 08/08/2014] [Indexed: 02/07/2023]
Abstract
Astrocytes have complex roles in health and disease, thus it is important to study the pathways that regulate their function. Here we report that lactosylceramide (LacCer) synthesized by β-1,4-galactosyltransferase 6 (B4GALT6) is upregulated in the central nervous system (CNS) of mice during chronic experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis (MS). LacCer acts in an autocrine manner to control astrocyte transcriptional programs that promote neurodegeneration. In addition, LacCer in astrocytes controls the recruitment and activation of microglia and CNS-infiltrating monocytes in a non-cell autonomous manner by regulating production of the chemokine CCL2 and granulocyte-macrophage colony-stimulating factor (GM-CSF), respectively. We also detected high B4GALT6 gene expression and LacCer concentrations in CNS MS lesions. Inhibition of LacCer synthesis in mice suppressed local CNS innate immunity and neurodegeneration in EAE and interfered with the activation of human astrocytes in vitro. Thus, B4GALT6 regulates astrocyte activation and is a potential therapeutic target for MS and other neuroinflammatory disorders.
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Affiliation(s)
- Lior Mayo
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Sunia A Trauger
- FAS Center for Systems Biology, Harvard University, Boston, Massachusetts, USA
| | - Manon Blain
- Neuroimmunology Unit, Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Meghan Nadeau
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Bonny Patel
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jorge I Alvarez
- Neuroimmunology Research Lab, Center for Excellence in Neuromics, Department of Neuroscience, University of Montreal, Quebec, Canada
| | - Ivan D Mascanfroni
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ada Yeste
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Pia Kivisäkk
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Keith Kallas
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Benjamin Ellezam
- Department of Pathology, University of Montreal and Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Rohit Bakshi
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Alexandre Prat
- Neuroimmunology Research Lab, Center for Excellence in Neuromics, Department of Neuroscience, University of Montreal, Quebec, Canada
| | - Jack P Antel
- Neuroimmunology Unit, Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Howard L Weiner
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Francisco J Quintana
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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143
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Shin JH, Park SH. The effect of intracellular trafficking of CD1d on the formation of TCR repertoire of NKT cells. BMB Rep 2014; 47:241-8. [PMID: 24755556 PMCID: PMC4163858 DOI: 10.5483/bmbrep.2014.47.5.077] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Indexed: 11/20/2022] Open
Abstract
CD1 molecules belong to non-polymorphic MHC class I-like proteins and present lipid antigens to T cells. Five different CD1 genes (CD1a-e) have been identified and classified into two groups. Group 1 include CD1a-c and present pathogenic lipid antigens to αβ T cells reminiscence of peptide antigen presentation by MHC-I molecules. CD1d is the only member of Group 2 and presents foreign and self lipid antigens to a specialized subset of αβ T cells, NKT cells. NKT cells are involved in diverse immune responses through prompt and massive production of cytokines. CD1d-dependent NKT cells are categorized upon the usage of their T cell receptors. A major subtype of NKT cells (type I) is invariant NKT cells which utilize invariant Vα14-Jα18 TCR alpha chain in mouse. The remaining NKT cells (type II) utilize diverse TCR alpha chains. Engineered CD1d molecules with modified intracellular trafficking produce either type I or type II NKT cell-defects suggesting the lipid antigens for each subtypes of NKT cells are processed/generated in different intracellular compartments. Since the usage of TCR by a T cell is the result of antigen-driven selection, the intracellular metabolic pathways of lipid antigen are a key in forming the functional NKT cell repertoire.
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Affiliation(s)
- Jung Hoon Shin
- Department of Life Sciences, Korea University, Seoul 136-701, Korea
| | - Se-Ho Park
- Department of Life Sciences, Korea University, Seoul 136-701, Korea
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144
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CD1d-unrestricted NKT cells are endowed with a hybrid function far superior than that of iNKT cells. Proc Natl Acad Sci U S A 2014; 111:12841-6. [PMID: 25143585 DOI: 10.1073/pnas.1323405111] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Invariant natural killer T (iNKT) cells to date represent the best example of cells known to have a hybrid function, representing both innate and adaptive immunity. Shared phenotypic similarities with NK cells together with a rapid response to a cytokine stimulus and a productive TCR engagement are the features that underline the hybrid nature of iNKT cells. Using these criteria, we provide molecular and functional evidence demonstrating that CD1d-independent (CD1d(ind)) NKT cells, a population of CD1d-unrestricted NKT cells, are endowed with a hybrid function far superior to that of iNKT cells: (i) an extensive shared program with NK cells, (ii) a closer Euclidian distance with NK cells, and (iii) the ability to respond to innate stimuli (Poly:IC) with cytotoxic potential in the same manner as NK cells identify a hybrid feature in CD1d(ind)NKT cells that truly fulfills the dual function of an NK and a T cell. Our finding that CD1d(ind)NKT cells are programmed to act like NK cells in response to innate signals while being capable of adaptive responses is unprecedented, and thus might reemphasize CD1d-unrestricted NKT cells as a subset of lymphocytes that could affect biological processes of antimicrobial and tumor immunity in a unique way.
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145
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Abstract
The CNS is considered an immune privileged site because its repertoire of highly immunogenic molecules remains unseen by the immune system under normal conditions. However, the mechanism underlying the inhibition of immune reactions within the CNS environment is not known, particularly in regions containing myelin, which contains several potent proteins and lipids that are invariably recognized as foreign by immune system cells. Sulfatides constitute a major component of myelin glycolipids and are known to be capable of raising an immune response. In this study, the effect of sulfatides on mouse T cell function and differentiation was analyzed in vitro and in vivo. We found profound inhibition of sulfatide-dependent T cell proliferation which was particularly pronounced in naive T helper (Th) cells. The inhibitory effect of sulfatides on T cell function was CD1d-independent and was not related to apoptosis or necrosis but did involve the induction of anergy as confirmed by the upregulation of early growth response 2 transcription factor. A glycolipid 3-sulfate group was essential for the T cell suppression, and the T cell inhibition was galectin-4-dependent. Sulfatide stimulation in vitro led to prominent suppression of Th17 differentiation, and this was related to a decrease in susceptibility to disease in a mouse model of multiple sclerosis, experimental autoimmune encephalomyelitis. Thus, we have defined a novel mechanism of negative regulation of T cell function by endogenous brain-derived glycolipids, a family of molecules traditionally deemphasized in favor of myelin proteins in studies of CNS autoimmunity.
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146
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Bogie JFJ, Stinissen P, Hendriks JJA. Macrophage subsets and microglia in multiple sclerosis. Acta Neuropathol 2014; 128:191-213. [PMID: 24952885 DOI: 10.1007/s00401-014-1310-2] [Citation(s) in RCA: 195] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/10/2014] [Accepted: 06/15/2014] [Indexed: 12/11/2022]
Abstract
Along with microglia and monocyte-derived macrophages, macrophages in the perivascular space, choroid plexus, and meninges are the principal effector cells in neuroinflammatory and neurodegenerative disorders. These phagocytes are highly heterogeneous cells displaying spatial- and temporal-dependent identities in the healthy, injured, and inflamed CNS. In the last decade, researchers have debated on whether phagocytes subtypes and phenotypes are pathogenic or protective in CNS pathologies. In the context of this dichotomy, we summarize and discuss the current knowledge on the spatiotemporal physiology of macrophage subsets and microglia in the healthy and diseased CNS, and elaborate on factors regulating their behavior. In addition, the impact of macrophages present in lymphoid organs on CNS pathologies is defined. The prime focus of this review is on multiple sclerosis (MS), which is characterized by inflammation, demyelination, neurodegeneration, and CNS repair, and in which microglia and macrophages have been extensively scrutinized. On one hand, microglia and macrophages promote neuroinflammatory and neurodegenerative events in MS by releasing inflammatory mediators and stimulating leukocyte activity and infiltration into the CNS. On the other hand, microglia and macrophages assist in CNS repair through the production of neurotrophic factors and clearance of inhibitory myelin debris. Finally, we define how microglia and macrophage physiology can be harnessed for new therapeutics aimed at suppressing neuroinflammatory and cytodegenerative events, as well as promoting CNS repair. We conclude that microglia and macrophages are highly dynamic cells displaying disease stage and location-specific fates in neurological disorders. Changing the physiology of divergent phagocyte subsets at particular disease stages holds promise for future therapeutics for CNS pathologies.
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Affiliation(s)
- Jeroen F J Bogie
- Hasselt University, Biomedisch Onderzoeksinstituut and Transnationale Universiteit Limburg, School of Life Sciences, Diepenbeek, Belgium
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147
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Zeissig S, Blumberg RS. Commensal microbial regulation of natural killer T cells at the frontiers of the mucosal immune system. FEBS Lett 2014; 588:4188-94. [PMID: 24983499 DOI: 10.1016/j.febslet.2014.06.042] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 06/18/2014] [Accepted: 06/18/2014] [Indexed: 12/17/2022]
Abstract
The commensal microbiota co-exists in a mutualistic relationship with its human host. Commensal microbes play critical roles in the regulation of host metabolism and immunity, while microbial colonization, conversely, is under control of host immunity and metabolic pathways. These interactions are of central importance to the maintenance of homeostasis at mucosal surfaces and their perturbation can provide the basis for atopic and chronic inflammatory diseases such as asthma and inflammatory bowel disease (IBD). Recent evidence has revealed that natural killer T (NKT) cells, a subgroup of T cells which recognizes self and microbial lipid antigens presented by CD1d, are key mediators of host-microbial interactions. Mucosal and systemic NKT cell development is under control of the commensal microbiota, while CD1d regulates microbial colonization and influences the composition of the intestinal microbiota. Here, we outline the mechanisms of bidirectional cross-talk between the microbiota and CD1d-restricted NKT cells and discuss how a perturbation of these processes can contribute to the pathogenesis of immune-mediated disorders at mucosal surfaces.
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Affiliation(s)
- Sebastian Zeissig
- Department of Internal Medicine I, University Medical Center Schleswig-Holstein, Kiel, Germany.
| | - Richard S Blumberg
- Division of Gastroenterology, Hepatology, and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
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148
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Maricic I, Halder R, Bischof F, Kumar V. Dendritic cells and anergic type I NKT cells play a crucial role in sulfatide-mediated immune regulation in experimental autoimmune encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2014; 193:1035-46. [PMID: 24973441 DOI: 10.4049/jimmunol.1302898] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
CD1d-restricted NKT cells can be divided into two groups: type I NKT cells use a semi-invariant TCR, whereas type II express a relatively diverse set of TCRs. A major subset of type II NKT cells recognizes myelin-derived sulfatides and is selectively enriched in the CNS tissue during experimental autoimmune encephalomyelitis (EAE). We have shown that activation of sulfatide-reactive type II NKT cells by sulfatide prevents induction of EAE. In this article, we have addressed the mechanism of regulation, as well as whether a single immunodominant form of synthetic sulfatide can treat ongoing chronic and relapsing EAE in SJL/J mice. We have shown that the activation of sulfatide-reactive type II NKT cells leads to a significant reduction in the frequency and effector function of myelin proteolipid proteins 139-151/I-A(s)-tetramer(+) cells in lymphoid and CNS tissues. In addition, type I NKT cells and dendritic cells (DCs) in the periphery, as well as CNS-resident microglia, are inactivated after sulfatide administration, and mice deficient in type I NKT cells are not protected from disease. Moreover, tolerized DCs from sulfatide-treated animals can adoptively transfer protection into naive mice. Treatment of SJL/J mice with a synthetic cis-tetracosenoyl sulfatide, but not α-galactosylceramide, reverses ongoing chronic and relapsing EAE. Our data highlight a novel immune-regulatory pathway involving NKT subset interactions leading to inactivation of type I NKT cells, DCs, and microglial cells in suppression of autoimmunity. Because CD1 molecules are nonpolymorphic, the sulfatide-mediated immune-regulatory pathway can be targeted for development of non-HLA-dependent therapeutic approaches to T cell-mediated autoimmune diseases.
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Affiliation(s)
- Igor Maricic
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| | - Ramesh Halder
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| | - Felix Bischof
- Department of Neurology, University of Tubingen, Tubingen D-72076, Germany
| | - Vipin Kumar
- Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
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149
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Rhost S, Lofbom L, Mansson JE, Lehuen A, Blomqvist M, Cardell SL. Administration of sulfatide to ameliorate type I diabetes in non-obese diabetic mice. Scand J Immunol 2014; 79:260-6. [PMID: 24795987 DOI: 10.1111/sji.12157] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The endogenous glycosphingolipid sulfatide is a ligand for CD1d-restricted type II natural killer T (NKT) lymphocytes. Through the action of these cells,sulfatide treatment has been shown to modulate the immune response in mouse models for autoimmune diseases, infections and tumour immunity. Sulfatide exists naturally in different organs including the pancreas, where sulfatide colocalizes with insulin within the Langerhans islet b-cells, targets for the immune destruction in type 1 diabetes (T1D). Human T1D patients, but not patients with type 2 diabetes nor healthy individuals, have autoantibodies against sulfatide in serum, suggesting that sulfatide induces an immune response in the natural course of T1D in humans. Here, we investigate sulfatide as an autoantigen and a modulator of autoimmune disease in the murine model forT1D, the non-obese diabetic (NOD) mice. We demonstrate that aged NOD mice displayed serum autoantibody reactivity to sulfatide; however, this reactivity did not correlate with onset of T1D. Repeated administration of sulfatide did not result in an increase in serum reactivity to sulfatide. Moreover, a multidose sulfatide treatment of female NOD mice initiated at an early (5 weeks of age),intermediate (8 weeks of age) or late (12 weeks of age) phase of T1D progression did not influence the incidence of disease. Thus, we demonstrate that a fraction of NOD mice develop autoantibody reactivity to sulfatide; however, we fail to demonstrate that sulfatide treatment reduces the incidence of T1D in this mouse strain.
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150
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Shekhar S, Joyee AG, Yang X. Invariant natural killer T cells: boon or bane in immunity to intracellular bacterial infections? J Innate Immun 2014; 6:575-84. [PMID: 24903638 DOI: 10.1159/000361048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 03/04/2014] [Indexed: 11/19/2022] Open
Abstract
Invariant natural killer T (iNKT) cells represent a specialized subset of innate lymphocytes that recognize lipid and glycolipid antigens presented to them by nonclassical MHC-I CD1d molecules and are able to rapidly secrete copious amounts of a variety of cytokines. iNKT cells possess the ability to modulate innate as well as adaptive immune responses against various pathogens. Intracellular bacteria are one of the most clinically significant human pathogens that effectively evade the immune system and cause a myriad of diseases of public health concern globally. Emerging evidence suggests that iNKT cells can confer immunity to intracellular bacteria but also inflict pathology in certain cases. We summarize the current knowledge on the contribution of iNKT cells in the host defense against intracellular bacterial infections, with a focus on the underlying mechanisms by which these cells induce protective or pathogenic reactions including the pathways of direct action (acting on infected cells) and indirect action (modulating dendritic, NK and T cells). The rational exploitation of iNKT cells for prophylactic and therapeutic purposes awaits a profound understanding of their functional biology.
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Affiliation(s)
- Sudhanshu Shekhar
- Laboratory for Infection and Immunity, Department of Medical Microbiology, University of Manitoba, Winnipeg, Man., Canada
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