1
|
Ciurkiewicz M, Floess S, Beckstette M, Kummerfeld M, Baumgärtner W, Huehn J, Beineke A. Transcriptome analysis following neurotropic virus infection reveals faulty innate immunity and delayed antigen presentation in mice susceptible to virus-induced demyelination. Brain Pathol 2021; 31:e13000. [PMID: 34231271 PMCID: PMC8549031 DOI: 10.1111/bpa.13000] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 01/13/2023] Open
Abstract
Viral infections of the central nervous system cause acute or delayed neuropathology and clinical consequences ranging from asymptomatic courses to chronic, debilitating diseases. The outcome of viral encephalitis is partially determined by genetically programed immune response patterns of the host. Experimental infection of mice with Theiler's murine encephalomyelitis virus (TMEV) causes diverse neurologic diseases, including TMEV‐induced demyelinating disease (TMEV‐IDD), depending on the used mouse strain. The aim of the present study was to compare initial transcriptomic changes occurring in the brain of TMEV‐infected SJL (TMEV‐IDD susceptible) and C57BL/6 (TMEV‐IDD resistant) mice. Animals were infected with TMEV and sacrificed 4, 7, or 14 days post infection. RNA was isolated from brain tissue and analyzed by whole‐transcriptome sequencing. Selected differences were confirmed on a protein level by immunohistochemistry. In mock‐infected SJL and C57BL/6 mice, >200 differentially expressed genes (DEGs) were detected. Following TMEV‐infection, the number of DEGs increased to >700. Infected C57BL/6 mice showed a higher expression of transcripts related to antigen presentation via major histocompatibility complex (MHC) I, innate antiviral immune responses and cytotoxicity, compared with infected SJL animals. Expression of many of those genes was weaker or delayed in SJL mice, associated with a failure of viral clearance in this mouse strain. SJL mice showed prolonged elevation of MHC II and chemotactic genes compared with C57BL/6 mice, which presumably facilitates the induction of chronic demyelinating disease. In addition, elevated expression of several genes associated with immunomodulatory or –suppressive functions was observed in SJL mice. The exploratory study confirms previous observations in the model and provides an extensive list of new immunologic parameters potentially contributing to different outcomes of viral encephalitis in two mouse strains.
Collapse
Affiliation(s)
| | - Stefan Floess
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Michael Beckstette
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Maren Kummerfeld
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Jochen Huehn
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Hannover, Germany
| |
Collapse
|
2
|
The nonclassical immune surveillance for ERAAP function. Curr Opin Immunol 2021; 70:105-111. [PMID: 34098489 DOI: 10.1016/j.coi.2021.05.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/11/2021] [Accepted: 05/17/2021] [Indexed: 01/04/2023]
Abstract
The peptide repertoire presented by MHC class I molecules on the cell surface is essential for the immune surveillance of intracellular pathogens and transformed cells. The generation of this peptide repertoire is critically dependent on the endoplasmic reticulum aminopeptidase associated with antigen processing (ERAAP). Loss of ERAAP function leads to the generation of a profoundly disrupted peptide repertoire including many novel and immunogenic peptides. Strikingly, a large fraction of these novel peptides on ERAAP-KO cells are presented by the nonclassical MHC Ib molecule, Qa-1b. One immunodominant Qa-1b-restricted novel peptide is recognized by a unique CD8+ T cell population showing features of both conventional cytotoxic T cells and unconventional innate-like T cells. While much remains to be uncovered, here we summarize the latest discoveries of our lab on the important immune surveillance of ERAAP function mediated by nonclassical MHC Ib molecules and their unusual cognate T cells.
Collapse
|
3
|
Lees JR. CD8+ T cells: The past and future of immune regulation. Cell Immunol 2020; 357:104212. [PMID: 32979764 DOI: 10.1016/j.cellimm.2020.104212] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/16/2020] [Accepted: 09/01/2020] [Indexed: 02/05/2023]
Abstract
Regulation of the adaptive immune response is critical for health. Regulatory activity can be found in multiple components of the immune system, however, the focus on particular components of the immune regulatory network has left many aspects of this critical immune component understudied. Here we review the evidence for activities of CD8+ T cells in immune homeostasis and regulation of autoimmune reactivity. The heterogeneous nature of identified CD8+ cell types are examined, and common phenotypes associated with functional activities are defined. The varying types of antigen signal crucial for CD8+ T cell regulatory activity are identified and the implications of these activation pathways for control of adaptive responses is considered. Finally, the promising capacity for transgenic antigen receptor directed cytotoxicity as a mechanism for modulation of autoimmunity is detailed.
Collapse
Affiliation(s)
- Jason R Lees
- Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States.
| |
Collapse
|
4
|
Lee H, Lee YS, Harenda Q, Pietrzak S, Oktay HZ, Schreiber S, Liao Y, Sonthalia S, Ciecko AE, Chen YG, Keles S, Sridharan R, Engin F. Beta Cell Dedifferentiation Induced by IRE1α Deletion Prevents Type 1 Diabetes. Cell Metab 2020; 31:822-836.e5. [PMID: 32220307 PMCID: PMC7346095 DOI: 10.1016/j.cmet.2020.03.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 01/12/2020] [Accepted: 02/29/2020] [Indexed: 01/15/2023]
Abstract
Immune-mediated destruction of insulin-producing β cells causes type 1 diabetes (T1D). However, how β cells participate in their own destruction during the disease process is poorly understood. Here, we report that modulating the unfolded protein response (UPR) in β cells of non-obese diabetic (NOD) mice by deleting the UPR sensor IRE1α prior to insulitis induced a transient dedifferentiation of β cells, resulting in substantially reduced islet immune cell infiltration and β cell apoptosis. Single-cell and whole-islet transcriptomics analyses of immature β cells revealed remarkably diminished expression of β cell autoantigens and MHC class I components, and upregulation of immune inhibitory markers. IRE1α-deficient mice exhibited significantly fewer cytotoxic CD8+ T cells in their pancreata, and adoptive transfer of their total T cells did not induce diabetes in Rag1-/- mice. Our results indicate that inducing β cell dedifferentiation, prior to insulitis, allows these cells to escape immune-mediated destruction and may be used as a novel preventive strategy for T1D in high-risk individuals.
Collapse
Affiliation(s)
- Hugo Lee
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA
| | - Yong-Syu Lee
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA
| | - Quincy Harenda
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA
| | - Stefan Pietrzak
- Department of Cell and Regenerative Biology, Wisconsin Institute for Discovery, Madison, WI 53706, USA
| | - Hülya Zeynep Oktay
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA
| | - Sierra Schreiber
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA
| | - Yian Liao
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA
| | - Shreyash Sonthalia
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA
| | - Ashley E Ciecko
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Yi-Guang Chen
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI 53226, USA; Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Sunduz Keles
- Department of Biostatistics & Medical Informatics and Department of Statistics, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53705, USA
| | - Rupa Sridharan
- Department of Cell and Regenerative Biology, Wisconsin Institute for Discovery, Madison, WI 53706, USA
| | - Feyza Engin
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA; Department of Medicine, Division of Endocrinology, Diabetes & Metabolism, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53705, USA.
| |
Collapse
|
5
|
Sheng H, Marrero I, Maricic I, Fanchiang SS, Zhang S, Sant'Angelo DB, Kumar V. Distinct PLZF +CD8αα + Unconventional T Cells Enriched in Liver Use a Cytotoxic Mechanism to Limit Autoimmunity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2019; 203:2150-2162. [PMID: 31554695 PMCID: PMC6783388 DOI: 10.4049/jimmunol.1900832] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 08/21/2019] [Indexed: 01/14/2023]
Abstract
Hepatic immune system is uniquely challenged to mount a controlled effector response to pathogens while maintaining tolerance to diet and microbial Ags. We have identified a novel population of innate-like, unconventional CD8αα+TCRαβ+ T cells in naive mice and in human peripheral blood, called CD8αα Tunc, capable of controlling effector T cell responses. They are NK1.1+ (CD161+ in human), express NK-inhibitory receptors, and express the promyelocytic leukemia zinc finger (PLZF) transcription factor that distinguishes them from conventional CD8+ T cells. These cells display a cytotoxic phenotype and use a perforin-dependent mechanism to control Ag-induced or T cell-mediated autoimmune diseases. CD8αα Tunc are dependent upon IL-15/IL-2Rβ signaling and PLZF for their development and/or survival. They are Foxp3-negative and their regulatory activity is associated with a functionally distinct Qa-1b-dependent population coexpressing CD11c and CD244. A polyclonal TCR repertoire, an activated/memory phenotype, and the presence of CD8αα Tunc in NKT- and in MAIT-deficient as well as in germ-free mice indicates that these cells recognize diverse self-protein Ags. Our studies reveal a distinct population of unconventional CD8+ T cells within the natural immune repertoire capable of controlling autoimmunity and also providing a new target for therapeutic intervention.
Collapse
Affiliation(s)
- Huiming Sheng
- Division of Gastroenterology, Department of Medicine, University of California San Diego, La Jolla, CA 92093
- Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| | - Idania Marrero
- Division of Gastroenterology, Department of Medicine, University of California San Diego, La Jolla, CA 92093
- Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| | - Igor Maricic
- Division of Gastroenterology, Department of Medicine, University of California San Diego, La Jolla, CA 92093
- Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| | - Shaohsuan S Fanchiang
- Division of Gastroenterology, Department of Medicine, University of California San Diego, La Jolla, CA 92093
- Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| | - Sai Zhang
- Rutgers University, New Brunswick, NJ 08901
| | | | - Vipin Kumar
- Division of Gastroenterology, Department of Medicine, University of California San Diego, La Jolla, CA 92093;
- Torrey Pines Institute for Molecular Studies, San Diego, CA 92121; and
| |
Collapse
|
6
|
Towards Clinical Translation of CD8 + Regulatory T Cells Restricted by Non-Classical Major Histocompatibility Complex Ib Molecules. Int J Mol Sci 2019; 20:ijms20194829. [PMID: 31569411 PMCID: PMC6801908 DOI: 10.3390/ijms20194829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 09/27/2019] [Accepted: 09/27/2019] [Indexed: 11/17/2022] Open
Abstract
In central lymphoid tissues, mature lymphocytes are generated and pathogenic autoreactive lymphocytes are deleted. However, it is currently known that a significant number of potentially pathogenic autoreactive lymphocytes escape the deletion and populate peripheral lymphoid tissues. Therefore, peripheral mechanisms are present to prevent these potentially pathogenic autoreactive lymphocytes from harming one’s own tissues. One such mechanism is dictated by regulatory T (Treg) cells. So far, the most extensively studied Treg cells are CD4+Foxp3+ Treg cells. However, recent clinical trials for the treatment of immune-mediated diseases using CD4+ Foxp3+ Treg cells met with limited success. Accordingly, it is necessary to explore the potential importance of other Treg cells such as CD8+ Treg cells. In this regard, one extensively studied CD8+ Treg cell subset is Qa-1(HLA-E in human)-restricted CD8+ Treg cells, in which Qa-1(HLA-E) molecules belong to a group of non-classical major histocompatibility complex Ib molecules. This review will first summarize the evidence for the presence of Qa-1-restricted CD8+ Treg cells and their regulatory mechanisms. Major discussions will then focus on the potential clinical translation of Qa-1-restricted CD8+ Treg cells. At the end, we will briefly discuss the current status of human studies on HLA-E-restricted CD8+ Treg cells as well as potential future directions.
Collapse
|
7
|
Abstract
Regulatory T cells are central mediators of immune regulation and play an essential role in the maintenance of immune homeostasis in the steady state and under pathophysiological conditions. Disruption of CD8 Treg-dependent recognition of Qa-1-restricted self-antigens can result in dysregulated immune responses, tissue damage, autoimmune disease and cancer. Recent progress in studies on regulatory T cells of the CD8 lineage has provided new biological insight into this specialized regulatory T cell subpopulation. Identification of the Helios transcription factor as an essential control element for the differentiation and function of CD8 regulatory T cells has led to a better understanding of the unique genetic program of these cells. Recent analyses of T-cell receptor usage and antigen recognition by Qa-1-restricted CD8 Treg have provided additional insight into the unusual biological function of this regulatory CD8 lineage. Here we summarize recent advances in our understanding of CD8 regulatory T cells with emphasis on lineage commitment, differentiation and stability.
Collapse
Affiliation(s)
- Hidetoshi Nakagawa
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, United States; Department of Immunology, Harvard Medical School, Boston, MA, United States
| | - Lei Wang
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, United States; Department of Immunology, Harvard Medical School, Boston, MA, United States
| | - Harvey Cantor
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, United States; Department of Immunology, Harvard Medical School, Boston, MA, United States.
| | - Hye-Jung Kim
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, United States; Department of Immunology, Harvard Medical School, Boston, MA, United States
| |
Collapse
|
8
|
Wu HL, Wiseman RW, Hughes CM, Webb GM, Abdulhaqq SA, Bimber BN, Hammond KB, Reed JS, Gao L, Burwitz BJ, Greene JM, Ferrer F, Legasse AW, Axthelm MK, Park BS, Brackenridge S, Maness NJ, McMichael AJ, Picker LJ, O'Connor DH, Hansen SG, Sacha JB. The Role of MHC-E in T Cell Immunity Is Conserved among Humans, Rhesus Macaques, and Cynomolgus Macaques. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 200:49-60. [PMID: 29150562 PMCID: PMC5736429 DOI: 10.4049/jimmunol.1700841] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 10/23/2017] [Indexed: 11/19/2022]
Abstract
MHC-E is a highly conserved nonclassical MHC class Ib molecule that predominantly binds and presents MHC class Ia leader sequence-derived peptides for NK cell regulation. However, MHC-E also binds pathogen-derived peptide Ags for presentation to CD8+ T cells. Given this role in adaptive immunity and its highly monomorphic nature in the human population, HLA-E is an attractive target for novel vaccine and immunotherapeutic modalities. Development of HLA-E-targeted therapies will require a physiologically relevant animal model that recapitulates HLA-E-restricted T cell biology. In this study, we investigated MHC-E immunobiology in two common nonhuman primate species, Indian-origin rhesus macaques (RM) and Mauritian-origin cynomolgus macaques (MCM). Compared to humans and MCM, RM expressed a greater number of MHC-E alleles at both the population and individual level. Despite this difference, human, RM, and MCM MHC-E molecules were expressed at similar levels across immune cell subsets, equivalently upregulated by viral pathogens, and bound and presented identical peptides to CD8+ T cells. Indeed, SIV-specific, Mamu-E-restricted CD8+ T cells from RM recognized antigenic peptides presented by all MHC-E molecules tested, including cross-species recognition of human and MCM SIV-infected CD4+ T cells. Thus, MHC-E is functionally conserved among humans, RM, and MCM, and both RM and MCM represent physiologically relevant animal models of HLA-E-restricted T cell immunobiology.
Collapse
Affiliation(s)
- Helen L Wu
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Roger W Wiseman
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI 53706
| | - Colette M Hughes
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Gabriela M Webb
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Shaheed A Abdulhaqq
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Benjamin N Bimber
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
| | - Katherine B Hammond
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Jason S Reed
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Lina Gao
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
- Knight Cancer Institute, Oregon Health and Science University, Portland, OR 97239
| | - Benjamin J Burwitz
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
| | - Justin M Greene
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Fidel Ferrer
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Alfred W Legasse
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
| | - Michael K Axthelm
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
| | - Byung S Park
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
- School of Public Health, Oregon Health and Science University, Portland, OR 97239
| | - Simon Brackenridge
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX1 2JD, United Kingdom
| | - Nicholas J Maness
- Division of Microbiology, Tulane National Primate Research Center, Covington, LA 70433
- Department of Microbiology and Immunology, School of Medicine, Tulane University Health Sciences Center, New Orleans, LA 70118; and
| | - Andrew J McMichael
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX1 2JD, United Kingdom
| | - Louis J Picker
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
| | - David H O'Connor
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI 53706
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, WI 53715
| | - Scott G Hansen
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Jonah B Sacha
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006;
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006
| |
Collapse
|
9
|
Ying G, Wang J, Kumar V, Zajonc DM. Crystal structure of Qa-1a with bound Qa-1 determinant modifier peptide. PLoS One 2017; 12:e0182296. [PMID: 28767728 PMCID: PMC5540586 DOI: 10.1371/journal.pone.0182296] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 07/14/2017] [Indexed: 11/29/2022] Open
Abstract
Qa-1 is a non-classical Major Histocompatibility (MHC) class I molecule that generally presents hydrophobic peptides including Qdm derived from the leader sequence of classical MHC I molecules for immune surveillance by NK cells. Qa-1 bound peptides derived from the TCR Vβ8.2 of activated T cells also activates CD8+ regulatory T cells to control autoimmunity and maintain self-tolerance. Four allotypes of Qa-1 (Qa-1a-d) are expressed that are highly conserved in sequence but have several variations that could affect peptide binding to Qa-1 or TCR recognition. Here, we determined the structure of Qa-1a with bound Qdm peptide. While the overall structure is very similar to that of Qa-1b, there are several amino acid differences around the peptide binding platform that could affect TCR recognition. Most notably, two amino acid substitutions are found in the pocket P2, which binds the anchor residue Met2 of the Qdm peptide. These residues affect both the size and shape of the binding pocket, as well as affect the charge at physiologic pH, suggesting Qa-1a and Qa-1b could present slightly distinct peptide reservoirs, which could presumably be recognized by different populations of CD8+ T cells.
Collapse
Affiliation(s)
- Ge Ying
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology (LJI), La Jolla, California, United States of America
| | - Jing Wang
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology (LJI), La Jolla, California, United States of America
| | - Vipin Kumar
- Department of Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Dirk M. Zajonc
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology (LJI), La Jolla, California, United States of America
- Department of Internal Medicine, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
- * E-mail:
| |
Collapse
|
10
|
Wang X, Zhang J, Baylink DJ, Li CH, Watts DM, Xu Y, Qin X, Walter MH, Tang X. Targeting Non-classical Myelin Epitopes to Treat Experimental Autoimmune Encephalomyelitis. Sci Rep 2016; 6:36064. [PMID: 27796368 PMCID: PMC5086895 DOI: 10.1038/srep36064] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 10/10/2016] [Indexed: 12/21/2022] Open
Abstract
Qa-1 epitopes, the peptides that bind to non-classical major histocompatibility complex Ib Qa-1 molecules and are recognized by Qa-1-restricted CD8+ regulatory T (Treg) cells, have been identified in pathogenic autoimmune cells that attack myelin sheath in experimental autoimmune encephalomyelitis (EAE, an animal model for multiple sclerosis [MS]). Additionally, immunization with such epitopes ameliorates the EAE. However, identification of such epitopes requires knowledge of the pathogenic autoimmune cells which are largely unknown in MS patients. Hence, we asked whether the CD8+ Treg cells could directly target the myelin sheath to ameliorate EAE. To address this question, we analyzed Qa-1 epitopes in myelin oligodendrocyte glycoprotein (MOG that is a protein in myelin sheath). Here, we report identification of a MOG-specific Qa-1 epitope. Immunization with this epitope suppressed ongoing EAE, which was abrogated by CD8+ T cell depletion. Additionally, the epitope immunization activated the epitope-specific CD8+ T cells which specifically accumulated in the CNS-draining cervical lymph nodes. Finally, CD8+ T cells primed by the epitope immunization transferred EAE suppression. Hence, this study reveals a novel regulatory mechanism mediated by the CD8+ Treg cells. We propose that immunization with myelin-specific HLA-E epitopes (human homologues of Qa-1 epitopes) is a promising therapy for MS.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Cell Line
- Dendritic Cells/cytology
- Dendritic Cells/immunology
- Disease Models, Animal
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Encephalomyelitis, Autoimmune, Experimental/therapy
- Epitopes/chemistry
- Epitopes/immunology
- Epitopes/therapeutic use
- Female
- Histocompatibility Antigens Class I/chemistry
- Histocompatibility Antigens Class I/immunology
- Histocompatibility Antigens Class I/metabolism
- Humans
- Lymph Nodes/cytology
- Mice
- Mice, Inbred C57BL
- Myelin-Oligodendrocyte Glycoprotein/chemistry
- Myelin-Oligodendrocyte Glycoprotein/metabolism
- Protein Binding
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
Collapse
Affiliation(s)
- Xiaohua Wang
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
- Division of Infectious Disease, Jinan Infectious Disease Hospital, Shandong University, 22029 Jing-Shi Road, Jinan, 250021, P.R. China
| | - Jintao Zhang
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
- Institute of Medical and Pharmaceutical Sciences, Zhengzhou University, Henan, China
| | - David J. Baylink
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
| | - Chih-Huang Li
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
- Department of Emergency Medicine, Chang-Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan
- Graduate Institute of Clinical Medical Sciences, School of Medicine, Chang-Gung university, Taoyuan, Taiwan
| | - Douglas M. Watts
- Department of Biological Sciences, University of Texas at El Paso, El Paso, TX, USA
| | - Yi Xu
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
| | - Xuezhong Qin
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
- Musculoskeletal Disease Center, Jerry L. Pettis Memorial Veterans Affairs Medical Center, Loma Linda, California, USA
| | - Michael H. Walter
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
| | - Xiaolei Tang
- Department of Medicine, Division of Regenerative Medicine, Loma Linda University, Loma Linda, California, USA
| |
Collapse
|
11
|
Friedenberg SG, Buhrman G, Chdid L, Olby NJ, Olivry T, Guillaumin J, O'Toole T, Goggs R, Kennedy LJ, Rose RB, Meurs KM. Evaluation of a DLA-79 allele associated with multiple immune-mediated diseases in dogs. Immunogenetics 2015; 68:205-17. [PMID: 26711123 DOI: 10.1007/s00251-015-0894-6] [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: 08/31/2015] [Accepted: 12/18/2015] [Indexed: 11/30/2022]
Abstract
Immune-mediated diseases are common and life-threatening disorders in dogs. Many canine immune-mediated diseases have strong breed predispositions and are believed to be inherited. However, the genetic mutations that cause these diseases are mostly unknown. As many immune-mediated diseases in humans share polymorphisms among a common set of genes, we conducted a candidate gene study of 15 of these genes across four immune-mediated diseases (immune-mediated hemolytic anemia, immune-mediated thrombocytopenia, immune-mediated polyarthritis (IMPA), and atopic dermatitis) in 195 affected and 206 unaffected dogs to assess whether causative or predictive polymorphisms might exist in similar genes in dogs. We demonstrate a strong association (Fisher's exact p = 0.0004 for allelic association, p = 0.0035 for genotypic association) between two polymorphic positions (10 bp apart) in exon 2 of one allele in DLA-79, DLA-79*001:02, and multiple immune-mediated diseases. The frequency of this allele was significantly higher in dogs with immune-mediated disease than in control dogs (0.21 vs. 0.12) and ranged from 0.28 in dogs with IMPA to 0.15 in dogs with atopic dermatitis. This allele has two non-synonymous substitutions (compared with the reference allele, DLA-79*001:01), resulting in F33L and N37D amino acid changes. These mutations occur in the peptide-binding pocket of the protein, and based upon our computational modeling studies, are likely to affect critical interactions with the peptide N-terminus. Further studies are warranted to confirm these findings more broadly and to determine the specific mechanism by which the identified variants alter canine immune system function.
Collapse
Affiliation(s)
- Steven G Friedenberg
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27607, USA. .,Comparative Medicine Institute, North Carolina State University, Raleigh, NC, 27607, USA.
| | - Greg Buhrman
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, 27695, USA
| | - Lhoucine Chdid
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27607, USA
| | - Natasha J Olby
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27607, USA.,Comparative Medicine Institute, North Carolina State University, Raleigh, NC, 27607, USA
| | - Thierry Olivry
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27607, USA.,Comparative Medicine Institute, North Carolina State University, Raleigh, NC, 27607, USA
| | - Julien Guillaumin
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Theresa O'Toole
- Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA, 01536, USA
| | - Robert Goggs
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Lorna J Kennedy
- Centre for Integrated Genomic Medical Research, University of Manchester, Manchester, UK, M13 9PT
| | - Robert B Rose
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, 27695, USA.,Comparative Medicine Institute, North Carolina State University, Raleigh, NC, 27607, USA
| | - Kathryn M Meurs
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, 27607, USA.,Comparative Medicine Institute, North Carolina State University, Raleigh, NC, 27607, USA
| |
Collapse
|
12
|
Guo J, Zhou X. Regulatory T cells turn pathogenic. Cell Mol Immunol 2015; 12:525-32. [PMID: 25942597 PMCID: PMC4579652 DOI: 10.1038/cmi.2015.12] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 01/21/2015] [Accepted: 01/23/2015] [Indexed: 12/31/2022] Open
Abstract
Foxp3(+) regulatory T (Treg) cells are considered a sub-lineage of CD4(+) T cells that are protective against autoimmunity due to their essential roles in maintaining immune homeostasis and self-tolerance. However, Treg cells are unstable in vivo in terms of lineage specialization and suppressive function. These unstable Treg cells play roles in the pathogenesis of diseases, which cause safety concerns regarding human Treg cell therapy. In this review, we highlight recent findings that demonstrate the pathogenic conversion of Treg cells in different disease models.
Collapse
|
13
|
Multiple Sclerosis and T Lymphocytes: An Entangled Story. J Neuroimmune Pharmacol 2015; 10:528-46. [PMID: 25946987 DOI: 10.1007/s11481-015-9614-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Accepted: 04/29/2015] [Indexed: 12/17/2022]
Abstract
Multiple sclerosis (MS) is the prototypic inflammatory disease of the central nervous system (CNS) characterized by multifocal areas of demyelination, axonal damage, activation of glial cells, and immune cell infiltration. Despite intensive years of research, the etiology of this neurological disorder remains elusive. Nevertheless, the abundance of immune cells such as T lymphocytes and their products in CNS lesions of MS patients supports the notion that MS is an immune-mediated disorder. An important body of evidence gathered from MS animal models such as experimental autoimmune encephalomyelitis (EAE), points to the central contribution of CD4 T lymphocytes in disease pathogenesis. Both Th1 (producing interferon-γ) and Th17 (producing interleukin 17) CD4 T lymphocytes targeting CNS self-antigens have been implicated in MS and EAE pathobiology. Moreover, several publications suggest that CD8 T lymphocytes also participate in the development of MS lesions. The migration of activated T lymphocytes from the periphery into the CNS has been identified as a crucial step in the formation of MS lesions. Several factors promote such T cell extravasation including: molecules (e.g., cell adhesion molecules) implicated in the T cell-blood brain barrier interaction, and chemokines produced by neural cells. Finally, once in the CNS, T lymphocytes need to be reactivated by local antigen presenting cells prior to enter the parenchyma where they can initiate damage. Further investigations will be necessary to elucidate the impact of environmental factors (e.g., gut microbiota) and CNS intrinsic properties (e.g., microglial activation) on this inflammatory neurological disease.
Collapse
|
14
|
Yu P, Bamford RN, Waldmann TA. IL-15-dependent CD8+ CD122+ T cells ameliorate experimental autoimmune encephalomyelitis by modulating IL-17 production by CD4+ T cells. Eur J Immunol 2015; 44:3330-41. [PMID: 25142300 DOI: 10.1002/eji.201444675] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 07/01/2014] [Accepted: 08/15/2014] [Indexed: 11/09/2022]
Abstract
Interleukin-15 (IL-15) is an inflammatory cytokine whose role in autoimmune diseases has not been fully elucidated. Th17 cells have been shown to play critical roles in experimental autoimmune encephalomyelitis (EAE) models. In this study, we demonstrate that blockade of IL-15 signaling by TMβ-1 mAb treatment aggravated EAE severity. The key mechanism was not NK-cell depletion but depletion of CD8+ CD122+ T cells. Adoptive transfer of exogenous CD8+ CD122+ T cells to TMβ-1-treated mice rescued animals from severe disease. Moreover, transfer of preactivated CD8+ CD122+ T cells prevented EAE development and significantly reduced IL-17 secretion. Naïve effector CD4+ CD25- T cells cultured with either CD8+ CD122+ T cells from wild-type mice or IL-15 transgenic mice displayed lower frequencies of IL-17A production with lower amounts of IL-17 in the supernatants when compared with production by effector CD4+ CD25- T cells cultured alone. Addition of a neutralizing antibody to IL-10 led to recovery of IL-17A production in Th17 cultures. Furthermore, coculture of CD8+ CD122+ T cells with effector CD4+ T cells inhibited their proliferation significantly, suggesting a regulatory function for IL-15 dependent CD8+ CD122+ T cells. Taken together, these observations suggest that IL-15, acting through CD8+ CD122+ T cells, has a negative regulatory role in reducing IL-17 production and Th17-mediated EAE inflammation.
Collapse
Affiliation(s)
- Ping Yu
- Lymphoid Malignancies Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | | | | |
Collapse
|
15
|
Pannemans K, Broux B, Goris A, Dubois B, Broekmans T, Van Wijmeersch B, Geraghty D, Stinissen P, Hellings N. HLA-E restricted CD8+ T cell subsets are phenotypically altered in multiple sclerosis patients. Mult Scler 2014; 20:790-801. [PMID: 24144875 DOI: 10.1177/1352458513509703] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 09/29/2013] [Indexed: 11/15/2022]
Abstract
BACKGROUND The importance of Qa-1 restricted CD8(+) T cells in regulating autoreactive T cell responses has been demonstrated in animal models for autoimmune disorders, including multiple sclerosis (MS). OBJECTIVE We hypothesize that their human variant, HLA-E restricted CD8(+) T cells, fulfills a similar regulatory role in man and that these cells are of importance in MS. METHODS A large cohort of MS patients and healthy controls was genotyped for the two known HLA-E polymorphisms. Flow cytometry was used to determine HLA-E expression kinetics and to phenotype HLA-E restricted CD8(+) T cells. Immunohistochemistry was performed to investigate HLA-E expression in the central nervous system (CNS) of MS patients. RESULTS HLA-E is upregulated on immune cells upon in vitro activation and this upregulation is polymorphism-dependent for T and B cells. T and B cells in lesions of MS patients show enhanced HLA-E expression. Furthermore, NKG2C(+)CD8(+) T cells of MS patients have a significantly lower Foxp3 expression, while NKG2A(+)CD8(+) T cells of MS patients produce higher levels of pro-inflammatory cytokines compared to those of healthy individuals. CONCLUSION Our study indicates that the HLA-E system is altered in MS and could play a regulatory role in disease.
Collapse
Affiliation(s)
- Kim Pannemans
- Biomedical Research Institute, Hasselt University, Belgium
| | - Bieke Broux
- Biomedical Research Institute, Hasselt University, Belgium
| | - An Goris
- Laboratory for Neuroimmunology, KULeuven, Belgium
| | | | - Tom Broekmans
- Biomedical Research Institute, Hasselt University, Belgium Department of Health Care, PHL University College, Belgium
| | | | - Daniel Geraghty
- Clinical Research Division, Fred Hutchinson Cancer Research Center, USA
| | - Piet Stinissen
- Biomedical Research Institute, Hasselt University, Belgium
| | - Niels Hellings
- Biomedical Research Institute, Hasselt University, Belgium
| |
Collapse
|
16
|
Rahim MMA, Tu MM, Mahmoud AB, Wight A, Abou-Samra E, Lima PDA, Makrigiannis AP. Ly49 receptors: innate and adaptive immune paradigms. Front Immunol 2014; 5:145. [PMID: 24765094 PMCID: PMC3980100 DOI: 10.3389/fimmu.2014.00145] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 03/20/2014] [Indexed: 11/13/2022] Open
Abstract
The Ly49 receptors are type II C-type lectin-like membrane glycoproteins encoded by a family of highly polymorphic and polygenic genes within the mouse natural killer (NK) gene complex. This gene family is designated Klra, and includes genes that encode both inhibitory and activating Ly49 receptors in mice. Ly49 receptors recognize class I major histocompatibility complex-I (MHC-I) and MHC-I-like proteins on normal as well as altered cells. Their functional homologs in humans are the killer cell immunoglobulin-like receptors, which recognize HLA class I molecules as ligands. Classically, Ly49 receptors are described as being expressed on both the developing and mature NK cells. The inhibitory Ly49 receptors are involved in NK cell education, a process in which NK cells acquire function and tolerance toward cells that express “self-MHC-I.” On the other hand, the activating Ly49 receptors recognize altered cells expressing activating ligands. New evidence shows a broader Ly49 expression pattern on both innate and adaptive immune cells. Ly49 receptors have been described on multiple NK cell subsets, such as uterine NK and memory NK cells, as well as NKT cells, dendritic cells, plasmacytoid dendritic cells, macrophages, neutrophils, and cells of the adaptive immune system, such as activated T cells and regulatory CD8+ T cells. In this review, we discuss the expression pattern and proposed functions of Ly49 receptors on various immune cells and their contribution to immunity.
Collapse
Affiliation(s)
- Mir Munir A Rahim
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa , Ottawa, ON , Canada
| | - Megan M Tu
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa , Ottawa, ON , Canada
| | - Ahmad Bakur Mahmoud
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa , Ottawa, ON , Canada ; College of Applied Medical Sciences, Taibah University , Madinah Munawwarah , Kingdom of Saudi Arabia
| | - Andrew Wight
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa , Ottawa, ON , Canada
| | - Elias Abou-Samra
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa , Ottawa, ON , Canada
| | - Patricia D A Lima
- Biomedical and Molecular Sciences, Queen's University , Kingston, ON , Canada
| | - Andrew P Makrigiannis
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa , Ottawa, ON , Canada
| |
Collapse
|
17
|
Hu D, Weiner HL, Ritz J. Identification of cytolytic CD161- CD56+ regulatory CD8 T cells in human peripheral blood. PLoS One 2013; 8:e59545. [PMID: 23527216 PMCID: PMC3602421 DOI: 10.1371/journal.pone.0059545] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 02/19/2013] [Indexed: 01/13/2023] Open
Abstract
We previously developed methods for establishing CD8 regulatory T cell (Treg) clones from normal human peripheral blood and demonstrated that these clones were capable of killing T cell receptor (TCR)-activated autologous CD4 T cells. Based on phenotypic and functional characterization of the CD8 Treg clones, we have identified a corresponding population of endogenous CD8 Treg in normal human peripheral blood. These cells appear morphologically as large lymphocytes with abundant cytoplasm and have the following unique phenotype: CD3+CD8+CD161−CD56+. The majority of CD8 Treg express CD45RA and CD62L with low or negative expression of CD45RO, CD25, CD27, CD28 and CCR7. The expression of CD94 and NKG2a on CD8 Treg was elevated compared to conventional CD8 T cells. Following in vitro activation, this T cell subset is capable of killing TCR-activated CD4 T cells. These studies identify an endogenous CD8 Treg population in humans and it will now be possible to characterize these cells in a variety of clinical conditions.
Collapse
Affiliation(s)
- Dan Hu
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Division of Hematologic Malignancies, Cancer Vaccine Center, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Howard L. Weiner
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jerome Ritz
- Division of Hematologic Malignancies, Cancer Vaccine Center, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
18
|
Rabinowitz K, Mayer L. Working out mechanisms of controlled/physiologic inflammation in the GI tract. Immunol Res 2013; 54:14-24. [PMID: 22466933 DOI: 10.1007/s12026-012-8315-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The mucosal immune system is distinct from its systemic counterpart by virtue of its enormous antigenic exposure (commensal flora, food antigen, pathogens). Despite this, the mucosal immune system maintains a response defined as controlled or physiologic inflammation. This is regulated by many different mechanisms, among which there are physical, cellular and soluble factors. Our laboratory has focused on unique Tregs in the gut controlled by, in one instance, intestinal epithelial cells that serve as non-professional antigen-presenting cells. We believe that intestinal epithelial cells, expressing classical and non-classical MHC molecules, serve to activate Tregs and thus maintain controlled or physiologic inflammation. In this review, we describe regulatory cytokines and T cells that are one part of the emphasis of our laboratory.
Collapse
Affiliation(s)
- Keren Rabinowitz
- Mount Sinai School of Medicine, Immunology Institute, 1425 Madison Avenue, Box 1089, New York, NY 10029, USA
| | | |
Collapse
|
19
|
Jørgensen PB, Livbjerg AH, Hansen HJ, Petersen T, Höllsberg P. Epstein-Barr virus peptide presented by HLA-E is predominantly recognized by CD8(bright) cells in multiple sclerosis patients. PLoS One 2012; 7:e46120. [PMID: 23049954 PMCID: PMC3457977 DOI: 10.1371/journal.pone.0046120] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 08/29/2012] [Indexed: 12/19/2022] Open
Abstract
Multiple sclerosis (MS) is associated with Epstein-Barr virus (EBV) infection, but impaired immune suppression may be part of the disease pathogenesis. CD8(+) T cells that are restricted by HLA-E exert an important immunoregulatory mechanism. To explore how EBV might interfere with immune regulation, we examined the expression of HLA-E and the frequency of CD8(+) cells recognizing HLA-E, presenting either an EBV peptide from the BZLF1 protein or a signal sequence peptide from HLA-A2, in relapsing remitting (MS-RR), primary progressive (MS-PP) MS patients, and healthy controls (HC). Treatment with IFN-α or EBV increased HLA-E expression on CD4(+) cells. However, only MS-PP had increased expression of HLA-E on resting CD4(+) cells when compared with HC (p<0.005). CD8(+) cells were divided into CD8(bright) and CD8(dim) cells by flow cytometry analyses. MS-RR had significantly fewer CD8(dim) cells than HC (p<0.003). Flow cytometry analyses were performed with HLA-E tetramers folded in the presence of the EBV or HLA-A2 peptide to identify HLA-E-interacting cells. MS-RR had increased frequency of CD8(bright) cells recognizing HLA-E/A2 (p=0.006) and HLA-E/BZLF1 (p=0.016). Conversely, MS-RR had fewer CD8(dim) cells that recognized HLA-E/BZLF1 (p=0.001), but this could be attributed to the overall lower number of CD8(dim) cells in MS-RR. Whereas HLA-E/A2 was predominantly recognized by CD8(dim) cells, HLA-E/BZLF1 was predominantly recognized by CD8(bright) cells in MS-RR and MS-PP, but not in HC. As expected, HLA-E/A2 was also recognized by CD8-negative cells in a CD94-dependent manner, whereas HLA-E/BZLF1 was poorly recognized in all groups by CD8-negative cells. These data demonstrate that MS-RR patients have expanded their CD8(bright) cells recognizing HLA-E/BZLF1. Moreover, HLA-E/BZLF1 appears to be recognized by the immune system in a different manner than HLA-E/A2.
Collapse
Affiliation(s)
| | | | - Hans J. Hansen
- Department of Neurology, MS Clinic, Aarhus University Hospital, Aarhus, Denmark
| | - Thor Petersen
- Department of Neurology, MS Clinic, Aarhus University Hospital, Aarhus, Denmark
| | - Per Höllsberg
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Danish Neuroscience Center, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
| |
Collapse
|
20
|
The immunomodulatory and neuroprotective effects of mesenchymal stem cells (MSCs) in experimental autoimmune encephalomyelitis (EAE): a model of multiple sclerosis (MS). Int J Mol Sci 2012; 13:9298-9331. [PMID: 22942767 PMCID: PMC3430298 DOI: 10.3390/ijms13079298] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 07/11/2012] [Accepted: 07/11/2012] [Indexed: 02/07/2023] Open
Abstract
Mesenchymal stem cells (MSCs) are multipotent cells that differentiate into the mesenchymal lineages of adipocytes, osteocytes and chondrocytes. MSCs can also transdifferentiate and thereby cross lineage barriers, differentiating for example into neurons under certain experimental conditions. MSCs have anti-proliferative, anti-inflammatory and anti-apoptotic effects on neurons. Therefore, MSCs were tested in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), for their effectiveness in modulating the pathogenic process in EAE to develop effective therapies for MS. The data in the literature have shown that MSCs can inhibit the functions of autoreactive T cells in EAE and that this immunomodulation can be neuroprotective. In addition, MSCs can rescue neural cells via a mechanism that is mediated by soluble factors, which provide a suitable environment for neuron regeneration, remyelination and cerebral blood flow improvement. In this review, we discuss the effectiveness of MSCs in modulating the immunopathogenic process and in providing neuroprotection in EAE.
Collapse
|
21
|
Two discreet subsets of CD8 T cells modulate PLP(91-110) induced experimental autoimmune encephalomyelitis in HLA-DR3 transgenic mice. J Autoimmun 2012; 38:344-53. [PMID: 22459490 DOI: 10.1016/j.jaut.2012.02.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 02/23/2012] [Accepted: 02/26/2012] [Indexed: 10/28/2022]
Abstract
Previously we showed that transgenic mice expressing human HLA-DR3 gene are susceptible to PLP(91-110) induced experimental autoimmune encephalomyelitis (EAE) and can serve as an animal model of multiple sclerosis (MS). HLA-DR3 mice with EAE showed increased number of CD8 T cells indicating their important role in disease pathogenesis. The role of CD8 T cells in MS, an inflammatory demyelinating disease of CNS, has been enigmatic as it has been assigned both regulatory and pathogenic roles. Therefore, to evaluate the role of CD8 T cells, we generated CD8 deficient HLA-DR3 transgenic mice (DR3.CD8(-/-)). Immunization with PLP(91-110) led to more severe EAE in DR3.CD8(-/-) mice compared to HLA-DR3 mice indicating a regulatory role for CD8 T cells. Interestingly, DR3.CD8(-/-) mice with EAE showed decreased CNS pathology compared to DR3 mice thus suggesting a pathogenic role for CD8 T cells. We show that these two subsets of CD8 T cells can be differentiated based on the surface expression of CD122 (IL-2 Rβ chain). CD8 T cells expressing CD122 (CD8+CD122+) play a regulatory role while CD8+CD122- T cells act as a pathogenic subset. CD122 expressing CD8 T cells are the regulatory subset of CD8 T cells and regulate the encephalitogenic CD4 T cells through direct modulation of antigen presenting cells and/or through the release of immunoregulatory cytokines such as IL-10, IFNγ and TGFβ. We also showed that adoptive transfer of CD8CD122- T cells caused increased spinal cord demyelination indicating that these are pathogenic subset of CD8 T cells. Our study suggests that CD8+ T cells play both regulatory as well as pathogenic role in disease pathogenesis of EAE. A better understanding of these subsets could aid in designing novel therapy for MS patients.
Collapse
|
22
|
Kim HJ, Cantor H. Regulation of self-tolerance by Qa-1-restricted CD8(+) regulatory T cells. Semin Immunol 2012; 23:446-52. [PMID: 22136694 DOI: 10.1016/j.smim.2011.06.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 06/07/2011] [Indexed: 10/14/2022]
Abstract
Mounting an efficient immune response to pathogens while avoiding damage to host tissues is the central task of the immune system. Emerging evidence has highlighted the contribution of the CD8(+) lineage of regulatory T cells to the maintenance of self-tolerance. Specific recognition of the MHC class Ib molecule Qa-1 complexed to peptides expressed by activated CD4(+) T cells by regulatory CD8(+) T cells triggers an inhibitory interaction that prevents autoimmune responses. Conversely, defective Qa-1-restricted CD8(+) regulatory activity can result in development of systemic autoimmune disease. Here, we review recent research into the cellular and molecular basis of these regulatory T cells, their mechanism of suppressive activity and the potential application of these insights into new treatments for autoimmune disease and cancer.
Collapse
Affiliation(s)
- Hye-Jung Kim
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, Harvard Medical School, 450 Brookline Avenue, Boston, MA 02215, USA
| | | |
Collapse
|
23
|
Mouse NK cell-mediated rejection of bone marrow allografts exhibits patterns consistent with Ly49 subset licensing. Blood 2011; 119:1590-8. [PMID: 22184406 DOI: 10.1182/blood-2011-08-374314] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Natural killer (NK) cells can mediate the rejection of bone marrow allografts and exist as subsets based on expression of inhibitory/activating receptors that can bind MHC. In vitro data have shown that NK subsets bearing Ly49 receptors for self-MHC class I have intrinsically higher effector function, supporting the hypothesis that NK cells undergo a host MHC-dependent functional education. These subsets also play a role in bone marrow cell (BMC) allograft rejection. Thus far, little in vivo evidence for this preferential licensing across mouse strains with different MHC haplotypes has been shown. We assessed the intrinsic response potential of the different Ly49(+) subsets in BMC rejection by using β2-microglobulin deficient (β2m(-/-)) mice as donors. Using congenic and allogeneic mice as recipients and depleting the different Ly49 subsets, we found that NK subsets bearing Ly49s, which bind "self-MHC" were found to be the dominant subset responsible for β2m(-/-) BMC rejection. This provides in vivo evidence for host MHC class I-dependent functional education. Interestingly, all H2(d) strain mice regardless of background were able to resist significantly greater amounts of β2m(-/-), but not wild-type BMC than H2(b) mice, providing evidence that the rheostat hypothesis regarding Ly49 affinities for MHC and NK-cell function impacts BMC rejection capability.
Collapse
|
24
|
Sajic M, Gregson N, Linington C, Hughes RAC, Smith KJ. The role of CD8(+) T cells in a model of multiple sclerosis induced with recombinant myelin oligodendrocyte glycoprotein. Mult Scler 2011; 18:286-98. [PMID: 21952095 DOI: 10.1177/1352458511424309] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND AND OBJECTIVES Since CD8(+) T cells may be important in the pathogenesis of multiple sclerosis (MS), we examined their role in the DA rat experimental autoimmune encephalomyelitis (EAE) model induced by immunization with recombinant myelin oligodendrocyte glycoprotein (rMOG). METHODS The inflammatory infiltrate in the spinal cord of affected animals was assessed by histology, electrophysiology and flow cytometry during the course of the disease (the first peak, remission and the second peak). The proportions of activated/memory effector (CD8(+)CD44(+)) and putative suppressor (CD8(+)CD28(-), CD8(+)CD25(high)) CD8(+) T cells in the draining lymph nodes were determined. To explore the role of CD8(+) T cells, similar experiments were performed in CD8(+) T cell depleted rats, before, during and after the first peak of the disease. RESULTS Throughout the disease, both CD4(+) T cells and macrophages/activated microglia outnumbered CD8(+) T cells within the spinal cord. The number of putative suppressor CD8(+) T cells increased significantly both during and after the first peak suggesting the induction of a regulatory CD8(+) T-cell response. However, antibody-mediated depletion of CD8(+) T cells before induction of the disease, or after the first peak, did not significantly alter the incidence, severity or course of rMOG-induced EAE. CONCLUSIONS The findings suggest that CD8(+) T cells do not play a significant role in the pathogenesis or regulation of EAE induced by rMOG in DA rats. In this respect, rMOG-induced EAE is not an appropriate model for studying the role of CD8(+) T cells in MS.
Collapse
Affiliation(s)
- Marija Sajic
- Department of Neuroinflammation, UCL Institute of Neurology, London, UK.
| | | | | | | | | |
Collapse
|
25
|
Khan AR, Dovedi SJ, Wilkinson RW, Pritchard DI. Tumor infiltrating regulatory T cells: tractable targets for immunotherapy. Int Rev Immunol 2011; 29:461-84. [PMID: 20839911 DOI: 10.3109/08830185.2010.508854] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Several studies have linked tumor-infiltration by regulatory T cells with poor patient outcome. Targeting the mechanisms by which regulatory T cells traffic to and persist in the tumor may circumvent tumor immune-escape by de-restricting T cell-mediated cytotoxicity. In this review, we describe the principle axes that govern regulatory T cell migration and the mechanisms that underpin their immunosuppressive activity in cancer. Inhibiting either the migration or function of regulatory T cells may enhance host-anti-cancer immune responses and as such are attractive and tractable targets for therapeutic intervention.
Collapse
Affiliation(s)
- Adnan R Khan
- Doctoral Training Centre for Targeted Therapeutics, School of Pharmacy, University of Nottingham, Nottingham, UK
| | | | | | | |
Collapse
|
26
|
Daniel C, Nolting J, von Boehmer H. Mechanisms of self-nonself discrimination and possible clinical relevance. Immunotherapy 2011; 1:631-44. [PMID: 20582233 DOI: 10.2217/imt.09.29] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
This review discusses different mechanisms that result in immunological tolerance, such as intrathymic deletion of immature T cells, intrathymic and extrathymic generation of regulatory T cells, effector mechanisms of regulatory T cells as well as molecular pathways involved in extrathymic generation of regulatory T cells in vivo and in vitro. These molecular mechanisms should enable investigators to develop clinical protocols aiming at the specific prevention of unwanted immune responses, thereby replacing indiscriminate immunosuppression that often has fatal consequences.
Collapse
Affiliation(s)
- Carolin Daniel
- Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Smith 736, Boston, MA 02115, USA.
| | | | | |
Collapse
|
27
|
Mars LT, Saikali P, Liblau RS, Arbour N. Contribution of CD8 T lymphocytes to the immuno-pathogenesis of multiple sclerosis and its animal models. Biochim Biophys Acta Mol Basis Dis 2010; 1812:151-61. [PMID: 20637863 DOI: 10.1016/j.bbadis.2010.07.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 06/21/2010] [Accepted: 07/06/2010] [Indexed: 12/17/2022]
Abstract
Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) characterized by multi-focal demyelination, axonal loss, and immune cell infiltration. Numerous immune mediators are detected within MS lesions, including CD4(+) and CD8(+) T lymphocytes suggesting that they participate in the related pathogenesis. Although CD4(+) T lymphocytes are traditionally considered the main actors in MS immunopathology, multiple lines of evidence suggest that CD8(+) T lymphocytes are also implicated in the pathogenesis. In this review, we outline the recent literature pertaining to the potential roles of CD8(+) T lymphocytes both in MS and its animal models. The CD8(+) T lymphocytes detected in MS lesions demonstrate characteristics of activated and clonally expanded cells supporting the notion that these cells actively contribute to the observed injury. Moreover, several experimental in vivo models mediated by CD8(+) T lymphocytes recapitulate important features of the human disease. Whether the CD8(+) T cells can induce or aggravate tissue destruction in the CNS needs to be fully explored. Strengthening our understanding of the pathogenic potential of CD8(+) T cells in MS should provide promising new avenues for the treatment of this disabling inflammatory disease.
Collapse
Affiliation(s)
- Lennart T Mars
- INSERM, U563, Centre de Physiopathologie de Toulouse Purpan, Hôpital Purpan, Toulouse, F-31300, France; Université Toulouse III, Paul-Sabatier, Toulouse, F-31400, France
| | | | | | | |
Collapse
|
28
|
Varthaman A, Khallou-Laschet J, Clement M, Fornasa G, Kim HJ, Gaston AT, Dussiot M, Caligiuri G, Herbelin A, Kaveri S, Cantor H, Nicoletti A. Control of T cell reactivation by regulatory Qa-1-restricted CD8+ T cells. THE JOURNAL OF IMMUNOLOGY 2010; 184:6585-91. [PMID: 20488793 DOI: 10.4049/jimmunol.0903109] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Administration of attenuated pathogenic T cell clones, a procedure known as T cell vaccination, induces CD8+ T cells specific for peptides derived from the Vbeta-chain of the TCR presented by the MHC class Ib molecule, Qa-1 expressed on the vaccine cells. These regulatory CD8+ T cells have the capacity to control the activation of endogenous T cells expressing the same TCR Vbeta-chain as the vaccinating cells. We hypothesized that vaccination with NKT cells could also induce Qa-1-restricted CD8+ T cells that would control NKT cell activation. We tested this hypothesis in a murine model of Con A-induced hepatitis that is induced by NKT cells. Vaccination with NKT cells effectively induced protective Qa-1-restricted CD8+ T cells that prevented hepatitis. Surprisingly, upon vaccination with T cells expressing Vbeta-chains irrelevant to NKT cells, we discovered that the specificity of vaccine-induced Qa-1-restricted CD8+ T cells was not limited to the Vbeta-chain of the vaccinating cells. We further show that these regulatory Qa-1-restricted CD8+ T cells arise spontaneously upon polyclonal activation of T cells in the absence of deliberate T cell vaccination. These experiments provide new insight into a CD8+ T cell compartment that regulates the immediate reactivation of conventional T cells and NKT cells.
Collapse
Affiliation(s)
- Aditi Varthaman
- Institut National de la Santé et de la Recherche Médicale U698, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Dinesh RK, Skaggs BJ, La Cava A, Hahn BH, Singh RP. CD8+ Tregs in lupus, autoimmunity, and beyond. Autoimmun Rev 2010; 9:560-8. [PMID: 20385256 DOI: 10.1016/j.autrev.2010.03.006] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 03/30/2010] [Indexed: 12/12/2022]
Abstract
While CD4(+)CD25(high) regulatory T cells (Tregs) have garnered much attention for their role in the maintenance of immune homeostasis, recent findings have shown that subsets of CD8(+) T cells (CD8(+) Tregs) display immunoregulatory functions as well. Both CD4(+) Tregs and CD8(+) Tregs appear impaired in number and/or function in several autoimmune diseases and in experimental animal models of autoimmunity, suggesting the possibility of immunotherapeutic targeting of these cells for improved management of autoimmune conditions. Our group has developed a strategy to induce CD8(+) Tregs in autoimmune mice through the use of a tolerogenic self-peptide, and new information has been gained on the phenotype, function and role of induced CD8(+) Tregs in autoimmunity. Here we present an overview of the role and mechanisms of action of CD8(+) Tregs in autoimmunity, with a special focus on lupus. We also discuss the potential role of CD8(+) Tregs in other diseases, including chronic infection and cancer.
Collapse
Affiliation(s)
- Ravi K Dinesh
- Division of Rheumatology, Dept of Medicine at the David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095-1670, USA
| | | | | | | | | |
Collapse
|
30
|
Johnson TA, Jirik FR, Fournier S. Exploring the roles of CD8+ T lymphocytes in the pathogenesis of autoimmune demyelination. Semin Immunopathol 2010; 32:197-209. [DOI: 10.1007/s00281-010-0199-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 01/28/2010] [Indexed: 02/07/2023]
|
31
|
Chen ML, Yan BS, Kozoriz D, Weiner HL. Novel CD8+ Treg suppress EAE by TGF-beta- and IFN-gamma-dependent mechanisms. Eur J Immunol 2009; 39:3423-35. [PMID: 19768696 PMCID: PMC2814307 DOI: 10.1002/eji.200939441] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although CD8+ Treg-mediated suppression has been described, CD8+ Treg remain poorly characterized. Here we identify a novel subset of CD8+ Treg that express latency-associated peptide (LAP) on their cell surface (CD8+LAP+ cells) and exhibit regulatory activity in vitro and in vivo. Only a small fraction of CD8+LAP+ cells express Foxp3 or CD25, although the expression levels of Foxp3 for these cells are higher than their LAP- counterparts. In addition to TGF-beta, CD8+LAP+ cells produce IFN-gamma, and these cells suppress EAE that is dependent on both TGF-beta and IFN-gamma. In an adoptive co-transfer model, CD8+LAP+ cells suppress myelin oligodendrocyte glycoprotein (MOG)-specific immune responses by inducing or expanding Foxp3+ cells and by inhibiting proliferation and IFN-gamma production in vivo. Furthermore, in vivo neutralization of IFN-gamma and studies with IFN-gamma-deficient mice demonstrate an important role for IFN-gamma production in the function of CD8+LAP+ cells. Our findings identify the underlying mechanisms that account for the immunoregulatory activity of CD8+ T cells and suggest that induction or amplification of CD8+LAP+ cells may be a therapeutic strategy to help control autoimmune processes.
Collapse
MESH Headings
- Adoptive Transfer
- Analysis of Variance
- Animals
- CD8 Antigens/metabolism
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/transplantation
- Cytokines/metabolism
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/metabolism
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Enzyme-Linked Immunosorbent Assay
- Female
- Forkhead Transcription Factors/metabolism
- Glycoproteins/immunology
- Interferon-gamma/genetics
- Interferon-gamma/metabolism
- Interleukin-2 Receptor alpha Subunit/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Inbred Strains
- Mice, Knockout
- Myelin Proteins
- Myelin-Associated Glycoprotein/chemistry
- Myelin-Associated Glycoprotein/immunology
- Myelin-Oligodendrocyte Glycoprotein
- Peptide Fragments/immunology
- Receptors, Interferon/genetics
- Receptors, Interferon/metabolism
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
- T-Lymphocytes, Regulatory/transplantation
- Transforming Growth Factor beta/genetics
- Transforming Growth Factor beta/metabolism
- Interferon gamma Receptor
Collapse
Affiliation(s)
- Mei-Ling Chen
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | | | | | | |
Collapse
|
32
|
Jiang H, Chess L. How the immune system achieves self-nonself discrimination during adaptive immunity. Adv Immunol 2009; 102:95-133. [PMID: 19477320 DOI: 10.1016/s0065-2776(09)01202-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We propose an "Avidity Model of Self-Nonself Discrimination" in which self-nonself discrimination is achieved by both central thymic selection and peripheral immune regulation. The conceptual framework that links these two events is the understanding that both in the thymus and in the periphery the survival or the fate of T cells is determined by the avidity of the interactions between T cell receptors (TCRs) on T cells, specific to any antigens and MHC/antigen peptides presented by antigen-presenting cells (APCs). We envision that the immune system achieves self-nonself discrimination, during adaptive immunity, not by recognizing the structural differences between self versus foreign antigens, but rather by perceiving the avidity of T cell activation. Intrathymic deletion of high avidity T cell clones responding to the majority of self-antigens generates a truncated peripheral self-reactive repertoire composed of mainly intermediate and low but devoid of high avidity T cells compared with the foreign-reactive repertoire. The existence of intermediate avidity self-reactive T cells in the periphery represents a potential danger of pathogenic autoimmunity inherited in each individual because potentially pathogenic self-reactive T cells are included in the pool of intermediate avidity T cells and can often be functionally activated to elicit autoimmune diseases. The distinct composition of peripheral T cell repertoires to self versus to foreign antigens provides a unique opportunity for the immune system to discriminate self from nonself, in the periphery, by selectively downregulating intermediate avidity T cells to both self and foreign antigens. Selective downregulation of the intermediate avidity T cell populations containing the potentially pathogenic self-reactive T cells enables the immune system to specifically control autoimmune diseases without damaging the effective anti-infection immunity, which is, largely, mediated by high avidity T cells specific to the infectious pathogens. In this regard, it has been recently shown that Qa-1-restricted CD8(+) T cells selectively downregulate intermediate avidity T cells, to both self and foreign antigens, and as a consequence, specifically dampen autoimmunity yet optimize the immune response to foreign antigens. Selective downregulation of intermediate avidity T cells is accomplished via specific recognition, by the Qa-1-restricted CD8(+) T cells, of particular Qa-1/self-peptide complexes, such as Qa-1/Hsp60sp, which function as a common surrogate target structure and preferentially expressed on the activated intermediate avidity T cells. This regulatory pathway thus represents one example of the peripheral mechanisms that the immune system evolved to complete self-nonself discrimination that is achieved, imperfectly, by thymic negative selection, in order to maintain self-tolerance. The conceptual framework of the "Avidity Model" differs from, but contains intellectual wisdom of certain conceptual elements of, the "Tunable Activation Thresholds Hypothesis," the "Danger Model," and the "Ergotypic Regulation Phenomenon." It provides a unified and simple paradigm to explain various seemingly unrelated biomedical problems inherent in immunological disorders that cannot be uniformly interpreted by any currently existing paradigms. The potential impact of the conceptual framework of the "Avidity Model" on our understanding of the development and control of commonly seen autoimmune diseases is also discussed.
Collapse
Affiliation(s)
- Hong Jiang
- Institute of Immunology, School of Medicine, Shanghai Jiaotong University, Shanghai, PR China
| | | |
Collapse
|
33
|
MHC class II-dependent T-T interactions create a diverse, functional and immunoregulatory reaction circle. Immunol Cell Biol 2008; 87:65-71. [PMID: 19030015 DOI: 10.1038/icb.2008.85] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Unlike conventional T cells, innate-like T cells such as natural killer (NK) T cells are selected by homotypic T-cell interactions. Recently, a few reports have shown that T-T CD4(+) T cells can be generated in a similar manner to that for NKT cells. These two types of cells share common functional properties such as rapid response to antigenic encounters and the potential for a panoply of cytokine secretion. However, T-T CD4(+) T cells differ from NKT cells in that they are restricted by highly polymorphic major histocompatibility complex (MHC) II molecules and have a diverse T-cell receptor repertoire. Additional example of T-T interactions was recently reported in which peripheral T cells re-circulate to the thymus and participate in the thymocyte selection process. In this review, we dissect the cellular mechanisms underlying the production of T-T CD4(+) and NKT cells, with particular emphasis on the differences between these two T-cell prototypes. Finally, we propose that T-T CD4(+) T cells serve two major functions: one as an acute-phase reactant against viral infection and the other is the generation of anti-ergotypic CD4(+) T cells for regulatory purposes. All of these features make it possible to create a diverse set of functional cells through MHC class II-restricted T-T interactions.
Collapse
|
34
|
Jiang H, Chess L. Qa-1/HLA-E-restricted regulatory CD8+ T cells and self-nonself discrimination: an essay on peripheral T-cell regulation. Hum Immunol 2008; 69:721-7. [PMID: 18822330 DOI: 10.1016/j.humimm.2008.08.279] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Revised: 08/10/2008] [Accepted: 08/12/2008] [Indexed: 01/14/2023]
Abstract
By discriminating self from nonself and controlling the magnitude and class of immune responses, the immune system mounts effective immunity against virtually any foreign antigens but avoids harmful immune responses to self. These are two equally important and related but distinct processes, which function in concert to ensure an optimal function of the immune system. Immunologically relevant clinical problems often occur because of failure of either process, especially the former. Currently, there is no unified conceptual framework to characterize the precise relationship between thymic negative selection and peripheral immune regulation, which is the basis for understanding self-non-self discrimination versus control of magnitude and class of immune responses. In this article, we explore a novel hypothesis of how the immune system discriminates self from nonself in the periphery during adaptive immunity. This hypothesis permits rational analysis of various seemingly unrelated biomedical problems inherent in immunologic disorders that cannot be uniformly interpreted by any currently existing paradigms. The proposed hypothesis is based on a unified conceptual framework of the "avidity model of peripheral T-cell regulation" that we originally proposed and tested, in both basic and clinical immunology, to understand how the immune system achieves self-nonself discrimination in the periphery.
Collapse
Affiliation(s)
- Hong Jiang
- Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, NY, USA.
| | | |
Collapse
|
35
|
Suzuki H, Shi Z, Okuno Y, Isobe KI. Are CD8+CD122+ cells regulatory T cells or memory T cells? Hum Immunol 2008; 69:751-4. [PMID: 18817826 DOI: 10.1016/j.humimm.2008.08.285] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Revised: 08/03/2008] [Accepted: 08/12/2008] [Indexed: 11/18/2022]
Abstract
We identified CD8(+)CD122(+) regulatory T cells in the mouse. Some immunologists consider CD8(+)CD122(+) cells to be memory T cells despite our report of their regulatory function. Here, we propose a dual phenotype of these cells. Murine CD8(+)CD122(+) T cells demonstrate both memory and regulatory features in their functional profiles. Human CD8(+)CXCR3(+) T cells, which are thought to be the human counterpart of murine CD8(+)CD122(+) regulatory T cells, do not match human central memory T cells of the CD8(+)CD45RA(-)CCR7(+) phenotype. Thus, we must consider human CD8(+) regulatory T cells and murine CD8(+) regulatory T cells separately. Of human CD8(+) regulatory T cells, CD8(+)CXCR3(+) regulatory T cells can be divided into further subsets and we may be able to distinguish memory T cells and regulatory T cells. Of murine CD8(+)CD122(+) regulatory T cells, it seems to be impossible to divide CD8(+)CD122(+)CD44(+)CD62L(+) regulatory T cells into further subsets at present, indicating that this single population of cells has activities of both regulatory T cells and memory T cells.
Collapse
Affiliation(s)
- Haruhiko Suzuki
- Department of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.
| | | | | | | |
Collapse
|
36
|
Suzuki M, Konya C, Goronzy JJ, Weyand CM. Inhibitory CD8+ T cells in autoimmune disease. Hum Immunol 2008; 69:781-9. [PMID: 18812196 DOI: 10.1016/j.humimm.2008.08.283] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2008] [Revised: 07/30/2008] [Accepted: 08/12/2008] [Indexed: 11/26/2022]
Abstract
Rheumatologists have long been focused on developing novel immunotherapeutic agents to manage such prototypic autoimmune diseases as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The ultimate challenge in providing immunosuppressive treatment for patients with RA and SLE has derived from the dilemma that both protective and harmful immune responses result from adaptive immune responses, mediated by highly diverse, antigen-specific T and B cells endowed with powerful effector functions and the ability for long-lasting memory. As regulatory/suppressor T cells can suppress immunity against any antigen, including self-antigens, they emerge as an ideal therapeutic target. Several distinct subtypes of CD8(+) suppressor cells (Ts) have been described that could find application in treating RA or SLE. In a xenograft model of human synovium, CD8(+)CD28(-)CD56(+) T cells effectively suppressed rheumatoid inflammation. Underlying mechanisms involve conditioning of antigen presenting cells (APC). Adoptively transferred CD8(+) T cells characterized by IL-16 secretion have also exhibited disease-inhibitory effects. In mice with polyarthritis, CD8(+) Ts suppressed inflammation by IFNgamma-mediated modulation of the tryptophan metabolism in APC. In SLE animal models, CD8(+) Ts induced by a synthetic peptide exerted suppressive activity mainly via the TGFbeta-Foxp3-PD1 pathway. CD8(+) Ts induced by histone peptides were found to downregulate disease activity by secreting TGFbeta. In essence, disease-specific approaches may be necessary to identify CD8(+) Ts optimally suited to treat immune dysfunctions in different autoimmune syndromes.
Collapse
Affiliation(s)
- Masakatsu Suzuki
- The Kathleen B. and Mason I. Lowance Center for Human Immunology and Rheumatology, Emory University, Atlanta, GA, USA
| | | | | | | |
Collapse
|
37
|
McPherson M, Wei B, Turovskaya O, Fujiwara D, Brewer S, Braun J. Colitis immunoregulation by CD8+ T cell requires T cell cytotoxicity and B cell peptide antigen presentation. Am J Physiol Gastrointest Liver Physiol 2008; 295:G485-92. [PMID: 18617557 PMCID: PMC2536787 DOI: 10.1152/ajpgi.90221.2008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Deficient immunoregulation by CD4+ T cells is an important susceptibility trait for inflammatory bowel disease, but the role of other regulatory cell types is less understood. This study addresses the role and mechanistic interaction of B cells and CD8+ T cells in controlling immune-mediated colitis. The genetic requirements for B cells and CD8+ T cells to confer protective immunoregulation were assessed by cotransfer with colitogenic Galphai2-/- T cells into immune-deficient mice. Disease activity in Galphai2-/- T cell recipients was evaluated by CD4+ T intestinal lymphocyte abundance, cytokine production levels, and large intestine histology. B cells deficient in B7.1/B7.2, CD40, major histocompatibility complex (MHC) II (Abb), or native B cell antigen receptor (MD4) were competent for colitis protection. However, transporter-1-deficient B cells failed to protect, indicating a requirement for peptide MHC I presentation to CD8+ T cells. CD8+ T cells deficient in native T cell receptor repertoire (OT-1) or cytolysis (perforin-/-) also were nonprotective. These finding reveal an integrated role for antigen-specific perforin-dependent CD8+ T cell cytotoxicity in colitis immunoregulatory and its efficient induction by a subset of mesenteric B lymphocytes.
Collapse
Affiliation(s)
- Michael McPherson
- Molecular Biology Institute, Department of Pathology and Laboratory Medicine, University of California, Los Angeles; and La Jolla Institute for Allergy and Immunology, San Diego, California
| | - Bo Wei
- Molecular Biology Institute, Department of Pathology and Laboratory Medicine, University of California, Los Angeles; and La Jolla Institute for Allergy and Immunology, San Diego, California
| | - Olga Turovskaya
- Molecular Biology Institute, Department of Pathology and Laboratory Medicine, University of California, Los Angeles; and La Jolla Institute for Allergy and Immunology, San Diego, California
| | - Daisuke Fujiwara
- Molecular Biology Institute, Department of Pathology and Laboratory Medicine, University of California, Los Angeles; and La Jolla Institute for Allergy and Immunology, San Diego, California
| | - Sarah Brewer
- Molecular Biology Institute, Department of Pathology and Laboratory Medicine, University of California, Los Angeles; and La Jolla Institute for Allergy and Immunology, San Diego, California
| | - Jonathan Braun
- Molecular Biology Institute, Department of Pathology and Laboratory Medicine, University of California, Los Angeles; and La Jolla Institute for Allergy and Immunology, San Diego, California
| |
Collapse
|
38
|
Rifa'i M, Shi Z, Zhang SY, Lee YH, Shiku H, Isobe KI, Suzuki H. CD8+CD122+ regulatory T cells recognize activated T cells via conventional MHC class I-alphabetaTCR interaction and become IL-10-producing active regulatory cells. Int Immunol 2008; 20:937-47. [PMID: 18495626 DOI: 10.1093/intimm/dxn052] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
CD8(+)CD122(+) regulatory T cells (CD8(+)CD122(+) Treg) are naturally occurring Treg that effectively suppress the proliferation and IFN-gamma production of both CD8(+) and CD4(+) target cells. This study investigated the molecular mechanisms of the recognition of target cells by CD8(+)CD122(+) Treg using an in vitro culture system that reconstitutes the regulatory action of these cells. Naive CD8(+)CD122(+) Treg co-cultured with pre-activated T cells became active Treg that produced IL-10 and suppressed IFN-gamma production from the target T cells. CD8(+)CD122(+) Treg effectively suppressed the IFN-gamma production of the target cells of syngeneic mouse strains but not of allogeneic mouse strains with incompatible MHC. By using MHC-congeneic mouse strains, MHC-restricted suppression by CD8(+)CD122(+) Treg was further confirmed. The blockade of cell surface molecules either on the Treg or on the target cells by specific blocking antibodies indicated that H-2K, H-2D, alphabetaTCR and CD8 were involved in the regulatory action but I-A and Qa-1 were not. These results indicate that CD8(+)CD122(+) Treg recognize already-activated T cells via the interaction of conventional MHC class I-alphabetaTCR and become active regulatory cells that produce IL-10 and suppress the target cells.
Collapse
Affiliation(s)
- Muhaimin Rifa'i
- Department of Immunology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | | | | | | | | | | | | |
Collapse
|
39
|
Correale J, Villa A. Isolation and characterization of CD8+ regulatory T cells in multiple sclerosis. J Neuroimmunol 2008; 195:121-34. [PMID: 18234356 DOI: 10.1016/j.jneuroim.2007.12.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Revised: 12/06/2007] [Accepted: 12/13/2007] [Indexed: 10/22/2022]
Abstract
To investigate CD8+ regulatory T cell influence on multiple sclerosis development, peripheral blood and cerebrospinal fluid (CSF) CD8+ T cell clones (TCCs) recognizing MBP(83-102) and MOG(63-87)-specific CD4+ T cells were isolated from 20 patients during acute exacerbations, 15 in remission and 15 controls. Blood and CSF CD8+ regulatory TCC cloning frequency decreased more during exacerbations than remissions or controls. Target cell pre-activation significantly enhanced CD8+ T granule-mediated cell killing of CD4+ targets, and was restricted by HLA-E. During exacerbations, killer-inhibitory receptor CD94/NKG2A expression was significantly higher in CD8+ TCCs, limiting their cytotoxic activity. Moreover, IL-15 and IFN-gamma significantly increased CD94 and NKG2A expression. These data provide evidence that CD94/NKG2A receptors play an important role in regulating T cell activity during the course of MS.
Collapse
Affiliation(s)
- Jorge Correale
- Department of Neurology, Raúl Carrea Institute for Neurological Research, FLENI, Montañeses 2325, (1428) Buenos Aires, Argentina.
| | | |
Collapse
|
40
|
Perceiving the avidity of T cell activation can be translated into peripheral T cell regulation. Proc Natl Acad Sci U S A 2007; 104:20472-7. [PMID: 18077361 DOI: 10.1073/pnas.0709878104] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The structure recognized by regulatory T cells that enables them to discriminate self from nonself in the periphery is one of the central issues of regulatory T cell biology. A link between immunoregulation and self-nonself discrimination has emerged from experiments showing that Qa-1-restricted CD8(+) T cells selectively down-regulate target T cells activated by the intermediate avidity of their own T cell antigen receptor-ligand interactions. Because the peripheral self-reactive T cell repertoire is devoid of high-avidity T cells compared with the foreign-reactive repertoire, as a result of thymic negative selection, the selective down-regulation of intermediate but not high-avidity T cells enables the immune system to suppress autoimmunity without damaging the ongoing immune response to foreign pathogens. However, the molecular mechanism delineating how avidity of T cell activation is perceived by the regulatory T cells has not been elucidated. Here we show that a heat shock peptide (Hsp60sp), coupled with the MHC class Ib molecule Qa-1, is a surrogate target structure that is preferentially expressed at a higher level on the intermediate avidity T cells and specifically recognized by the Qa-1-restricted CD8(+) T cells. The biological significance of this observation was confirmed by the ability of Hsp60sp-loaded relevant dendritic cells to induce a Qa-1-restricted CD8(+) T cell-mediated protection from autoimmune encephalopathy in the experimental allergic encephalomyelitis model. Thus, perceiving the avidity of T cell activation can be translated into peripheral T cell regulation to discriminate self from nonself in the periphery to maintain self-tolerance.
Collapse
|
41
|
Fazilleau N, Delarasse C, Motta I, Fillatreau S, Gougeon ML, Kourilsky P, Pham-Dinh D, Kanellopoulos JM. T cell repertoire diversity is required for relapses in myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2007; 178:4865-75. [PMID: 17404267 DOI: 10.4049/jimmunol.178.8.4865] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Comparison of TCRalphabeta repertoires of myelin oligodendrocyte glycoprotein (MOG)-specific T lymphocytes in C57BL/6 and TdT-deficient littermates (TdT(-/-)) generated during experimental autoimmune encephalomyelitis (EAE) highlights a link between a diversified TCRalphabeta repertoire and EAE relapses. At the onset of the disease, the EAE-severity is identical in TdT(+/-) and TdT(-/-) mice and the neuropathologic public MOG-specific T cell repertoires express closely similar public Valpha-Jalpha and Vbeta-Jbeta rearrangements in both strains. However, whereas TdT(+/+) and TdT(+/-) mice undergo successive EAE relapses, TdT(-/-) mice recover definitively and the lack of relapses does not stem from dominant regulatory mechanisms. During the first relapse of the disease in TdT(+/-) mice, new public Valpha-Jalpha and Vbeta-Jbeta rearrangements emerge that are distinct from those detected at the onset of the disease. Most of these rearrangements contain N additions and are found in CNS-infiltrating T lymphocytes. Furthermore, CD4(+) T splenocytes bearing these rearrangements proliferate to the immunodominant epitope of MOG and not to other immunodominant epitopes of proteolipid protein and myelin basic protein autoantigens, excluding epitope spreading to these myelin proteins. Thus, in addition to epitope spreading, a novel mechanism involving TCRalphabeta repertoire diversification contributes to autoimmune progression.
Collapse
Affiliation(s)
- Nicolas Fazilleau
- Institut National de la Santé et de la Recherche Médicale, Unité 277, Institut Pasteur, Paris, France
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Derré L, Corvaisier M, Charreau B, Moreau A, Godefroy E, Moreau-Aubry A, Jotereau F, Gervois N. Expression and release of HLA-E by melanoma cells and melanocytes: potential impact on the response of cytotoxic effector cells. THE JOURNAL OF IMMUNOLOGY 2006; 177:3100-7. [PMID: 16920947 DOI: 10.4049/jimmunol.177.5.3100] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
HLA-E are nonclassical MHC molecules with poorly characterized tissue distribution and functions. Because of their capacity to bind the inhibitory receptor, CD94/NKG2A, expressed by NK cells and CTL, HLA-E molecules might play an important role in immunomodulation. In particular, expression of HLA-E might favor tumor cell escape from CTL and NK immunosurveillance. To address the potential role of HLA-E in melanoma immunobiology, we assessed the expression of these molecules ex vivo in human melanoma biopsies and in melanoma and melanocyte cell lines. Melanoma cell lines expressed no or low surface, but significant intracellular levels of HLA-E. We also report for the first time that some of them produced a soluble form of this molecule. IFN-gamma significantly increased the surface expression of HLA-E and the shedding of soluble HLA-E by these cells, in a metalloproteinase-dependent fashion. In contrast, melanocyte cell lines constitutively expressed HLA-E molecules that were detectable both at the cell surface and in the soluble form, at levels that were poorly affected by IFN-gamma treatment. On tumor sections, a majority of tumor cells of primary, but a low proportion of metastatic melanomas (30-70 and 10-20%, respectively), expressed HLA-E. Finally, HLA-E expression at the cell surface of melanoma cells decreased their susceptibility to CTL lysis. These data demonstrate that HLA-E expression and shedding are normal features of melanocytes, which are conserved in melanoma cells of primary tumors, but become dependent on IFN-gamma induction after metastasis. The biological significance of these findings warrants further investigation.
Collapse
Affiliation(s)
- Laurent Derré
- Institut National de la Santé et de la Recherche Médicale Unité 601, Nantes, France
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
The immune system is not only well equipped to control infections but also tightly controlled to prevent autoimmune disease. Despite the negative selection of T-cell clones in the thymus, mature T cells capable of recognizing self-antigens are present in every individual. Several types of specialized regulatory cells maintain homeostasis and prevent expansion of autoreactive T cells. In this issue of Immunological Reviews, the role of CD4+ regulatory T cells is extensively discussed. Suppression of T-cell responses by CD8+ T cells has received less attention. Here, we review research on Qa-1-restricted CD8+ regulatory T cells. We focus on the role of this class Ib major histocompatibility complex (MHC) molecule in both CD8+ regulatory T-cell activity and protection of activated T cells.
Collapse
Affiliation(s)
- Linrong Lu
- Department of Cancer Immunology & AIDS, Dana Farber Cancer Institute, Boston, MA, USA
| | | | | |
Collapse
|
44
|
Abstract
Immunological self-tolerance is maintained through diverse mechanisms, including deletion of autoreactive immune cells following confrontation with autoantigen in the thymus or in the periphery and active suppression by regulatory cells. A third way to prevent autoimmunity is by hiding self tissues behind a tissue barrier impermeable for circulating immune cells. The latter mechanism has been held responsible for self-tolerance within the nervous tissue. Indeed, the nervous tissues enjoy a conditionally privileged immune status: they are normally unreachable for self-reactive T and B cells, they lack lymphatic drainage, and they are deficient in local antigen-presenting cells. Yet the immune system is by no means fully ignorant of the nervous structures. An ever-growing number of brain specific autoantigens is expressed within the thymus, which ensures an early confrontation with the unfolding T cell repertoire, and there is evidence that B cells also contact CNS-like structures outside of the brain. Then pathological processes such as neurodegeneration commonly lift the brain's immune privilege, shifting the local milieus from immune-hostile to immune-friendly. Finally, brain-reactive T cells, which abound in the healthy immune repertoire, but remain innocuous throughout life, can be activated and gain access to their target tissues. On their way, they take an ordered migration through peripheral lymphoid tissues and blood circulation, and undergo a profound reprogramming of their gene expression profile, which renders them fit to enter the nervous system and to interact with local cellule elements.
Collapse
Affiliation(s)
- H Wekerle
- MPI Neuroimmunology, Martinsried, Germany.
| |
Collapse
|
45
|
Metwali A, Setiawan T, Blum AM, Urban J, Elliott DE, Hang L, Weinstock JV. Induction of CD8+ regulatory T cells in the intestine by Heligmosomoides polygyrus infection. Am J Physiol Gastrointest Liver Physiol 2006; 291:G253-9. [PMID: 16825660 DOI: 10.1152/ajpgi.00409.2005] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This study determined whether Heligmosomoides polygyrus induces intestinal regulatory T cells. Splenic T cells proliferate strongly when cultured with anti-CD3 and antigen-presenting cells (APC). Lamina propria T cells from mice with H. polygyrus mixed with normal splenic T cells from uninfected mice inhibited proliferation over 90%. Lamina propria T cells from mice without H. polygyrus only modestly affected T cell proliferation. The worm-induced regulatory T cell was CD8+ and required splenic T cell contact to inhibit proliferation. The regulation also was IL-10 independent, but TAP-dependent, suggesting that it requires major histocompatibility complex (MHC) class I interaction. Additional studies employed mice with transgenic T cells that did not express functional TGF-beta receptors. The lamina propria T regulator inhibited proliferation of these transgenic T cells nearly 100%, suggesting that TGF-beta signaling via the T cell was not required. CD8+ T cells were needed for worms to reverse piroxicam-induced colitis in Rag mice (T and B cell deficient) reconstituted with IL-10-/- T cells. Thus H. polygyrus induces a regulatory CD8+ lamina propria T cell that inhibits T cell proliferation and that appears to have a role in control of colitis.
Collapse
Affiliation(s)
- Ahmed Metwali
- Department of Internal Medicine, University of Iowa, Iowa City, USA
| | | | | | | | | | | | | |
Collapse
|
46
|
Franco A, Albani S. Translating the concept of suppressor/regulatory T cells to clinical applications. Int Rev Immunol 2006; 25:27-47. [PMID: 16669133 DOI: 10.1080/08830180500544506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The in vivo expansion of suppressor/regulatory T cells (Tregs) is a desirable event in autoimmunity and transplantation. Here we summarize the general rules involved in antigen recognition by T cells and describe Tregs and their requirements, discussing different levels of immune intervention.
Collapse
Affiliation(s)
- Alessandra Franco
- Department of Medicine and Pediatrics, University of California, San Diego, La Jolla, California 92093-0731, USA
| | | |
Collapse
|
47
|
Affiliation(s)
- Hong Jiang
- Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
| | | |
Collapse
|
48
|
Noble A, Giorgini A, Leggat JA. Cytokine-induced IL-10-secreting CD8 T cells represent a phenotypically distinct suppressor T-cell lineage. Blood 2006; 107:4475-83. [PMID: 16467201 DOI: 10.1182/blood-2005-10-3994] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Populations of regulatory T cells (Tregs) control autoimmune and allergic immunopathology induced by self or foreign antigens. Several types of CD4(+) MHC class II-restricted Treg populations have been characterized, but the biology of CD8(+), MHC class I-restricted Tregs is less understood. We show here that CD8(+) Tregs are rapidly generated in the presence of IL-4 and IL-12, produce IL-10, and exhibit a unique cell-surface phenotype with coexpression of activation and naive cell-associated markers. They block activation of naive or effector T cells and suppress IgG/IgE antibody responses and graft-versus-host disease in vivo. Suppression is dependent on cell contact and mediated by direct T-cell-T-cell interaction that antagonizes T-cell-receptor (TCR) signals. The data establish the existence of a CD8 T-cell suppressor effector subset distinct in both phenotype and function from T cytotoxic 1 (Tc1) and Tc2 cells. Production of such CD8 Tregs has potential for cell-based therapy of CD4 or CD8 T-cell-mediated disease.
Collapse
|
49
|
de Lavareille A, Prigogine C, Paulart F, Nagy N, Habran C, Haddou NO, Le Moine A, Salmon I, Goldman M, Flamand V. Regulatory Role of Host CD8+ T Lymphocytes in Experimental Graft-versus-Host Disease across a Single Major Histocompatibility Complex Class II Incompatibility. Transplantation 2005; 80:1293-9. [PMID: 16314798 DOI: 10.1097/01.tp.0000178380.85521.75] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND CD8+ T cells are known to regulate type 2 helper T cell (Th2) alloreactive immune responses but their mode of activation is unclear. We investigated the role of host CD8+ T cells in experimental Th2-type graft-versus-host disease (GVHD) where donor/recipient disparity is restricted to a single major histocompatibility complex (MHC) class II antigen. METHODS Immunoglobulin (Ig) E serum levels, eosinophilia and lymphoid tissue hyperplasia were compared after injection of bm12 CD4+ T cells in either wild-type or CD8+ T cell-deficient (CD8-/-) C57BL/6 mice. In vitro, we explored effects of the addition of CD8+ T cells from wild-type or IFN-gamma-/- mice in mixed leukocyte cultures prepared with beta2 microglobulin-deficient (beta2m-/-) CD4+ T cells as responders or beta2m dendritic cells as stimulators. RESULTS HyperIgE resolved after 3 weeks in wild-type hosts whereas it persisted for 6 weeks in CD8-/- hosts. Eosinophil infiltrates in lymph nodes were significantly enhanced in CD8-/- hosts. Increased serum levels of IL-5 and IL-13 in CD8-/- hosts confirmed the enhancement of Th2-type responses in the context of recipient CD8+ T cell deficiency. Hyperplasia of lymph nodes and spleen were similar in both groups, as well as in vivo proliferation of donor CD4+ T cells. In vitro, CD8+ T cell regulation of the alloreactive Th2 response depended on their production of IFN-gamma and did not require expression of beta2m on CD4+ T cells or antigen-presenting cells. CONCLUSIONS Host CD8+ T cells regulate alloreactive Th2 responses during graft-versus-host disease through an IFN-gamma dependent pathway, independently of the recognition of beta2m-associated MHC class I molecules.
Collapse
Affiliation(s)
- Aurore de Lavareille
- Institute for Medical Immunology, Université Libre de Bruxelles, and Department of Pathology, Erasme Hospital, Brussels, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Walter U, Santamaria P. CD8+ T cells in autoimmunity. Curr Opin Immunol 2005; 17:624-31. [PMID: 16226438 DOI: 10.1016/j.coi.2005.09.014] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2005] [Accepted: 09/20/2005] [Indexed: 10/25/2022]
Abstract
Mounting evidence shows that CD8(+) T cells contribute to the initiation, progression and regulation of several pathogenic autoimmune responses in which these cells were not previously thought to play a major role. CD8(+) T cells can kill target cells directly, by recognizing peptide-MHC complexes on target cells, or indirectly, by secreting cytokines capable of signaling through death receptors expressed on the target cell surface. Autoreactive CD8(+) T cells can also contribute to autoimmunity by releasing cytokines capable of increasing the susceptibility of target cells to cytotoxicity, or by secreting chemokines that attract other immune cells to the site of autoimmunity. Autoreactive CD8(+) T cells can also downregulate autoimmune responses. Recent important advances include a mechanistic understanding of events leading to the activation and recruitment of autoreactive CD8(+) T cells in certain autoimmune responses and a greater appreciation of the diverse roles that these T cells play in autoimmunity.
Collapse
Affiliation(s)
- Ulrich Walter
- Julia McFarlane Diabetes Research Centre and Department of Microbiology and Infectious Diseases, Faculty of Medicine, The University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | | |
Collapse
|