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Adu-Berchie K, Obuseh FO, Mooney DJ. T Cell Development and Function. Rejuvenation Res 2023; 26:126-138. [PMID: 37154728 PMCID: PMC10460695 DOI: 10.1089/rej.2023.0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023] Open
Abstract
T cells play critical roles in the immune system, including in responses to cancer, autoimmunity, and tissue regeneration. T cells arise from common lymphoid progenitors (CLPs) that differentiate from hematopoietic stem cells in the bone marrow. CLPs then traffic to the thymus, where they undergo thymopoiesis through a number of selection steps, resulting in mature single positive naive CD4 helper or CD8 cytotoxic T cells. Naive T cells are home to secondary lymphoid organs like lymph nodes and are primed by antigen-presenting cells, which scavenge for both foreign and self-antigens. Effector T cell function is multifaceted, including direct target cell lysis and secretion of cytokines, which regulate the functions of other immune cells (refer to "Graphical Abstract"). This review will discuss T cell development and function, from the development of lymphoid progenitors in the bone marrow to principles that govern T cell effector function and dysfunction, specifically within the context of cancer.
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Affiliation(s)
- Kwasi Adu-Berchie
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA
- The Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts, USA
| | - Favour O. Obuseh
- The Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts, USA
- Harvard-MIT Health Sciences and Technology, Cambridge, Massachusetts, USA
| | - David J. Mooney
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA
- The Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts, USA
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2
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Kaneko KB, Tateishi R, Miyao T, Takakura Y, Akiyama N, Yokota R, Akiyama T, Kobayashi TJ. Quantitative analysis reveals reciprocal regulations underlying recovery dynamics of thymocytes and thymic environment in mice. Commun Biol 2019; 2:444. [PMID: 31815199 PMCID: PMC6884561 DOI: 10.1038/s42003-019-0688-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 11/10/2019] [Indexed: 01/17/2023] Open
Abstract
Thymic crosstalk, a set of reciprocal regulations between thymocytes and the thymic environment, is relevant for orchestrating appropriate thymocyte development as well as thymic recovery from various exogenous insults. In this work, interactions shaping thymic crosstalk and the resultant dynamics of thymocytes and thymic epithelial cells are inferred based on quantitative analysis and modeling of the recovery dynamics induced by irradiation. The analysis identifies regulatory interactions consistent with known molecular evidence and reveals their dynamic roles in the recovery process. Moreover, the analysis also predicts, and a subsequent experiment verifies, a previously unrecognized regulation of CD4+CD8+ double positive thymocytes which temporarily increases their proliferation rate upon the decrease in their population size. Our model establishes a pivotal step towards the dynamic understanding of thymic crosstalk as a regulatory network system.
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Affiliation(s)
- Kazumasa B. Kaneko
- Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo, 113-8656 Japan
| | - Ryosuke Tateishi
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Takahisa Miyao
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Yuki Takakura
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Nobuko Akiyama
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Ryo Yokota
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505 Japan
| | - Taishin Akiyama
- RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Tetsuya J. Kobayashi
- Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo, 113-8656 Japan
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku Tokyo, 153-8505 Japan
- PREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama, 332-0012 Japan
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3
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Abstract
Generating and maintaining a diverse repertoire of naive T cells is essential for protection against pathogens, and developing a mechanistic and quantitative description of the processes involved lies at the heart of our understanding of vertebrate immunity. Here, we review the biology of naive T cells from birth to maturity and outline how the integration of mathematical models and experiments has helped us to develop a full picture of their life histories.
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Affiliation(s)
- Benedict Seddon
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Hospital, London, UK
| | - Andrew J Yates
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York
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4
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Ruscher R, Hogquist KA. Development, ontogeny, and maintenance of TCRαβ + CD8αα IEL. Curr Opin Immunol 2019; 58:83-88. [PMID: 31146182 DOI: 10.1016/j.coi.2019.04.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 04/19/2019] [Indexed: 02/07/2023]
Abstract
The intestinal epithelium is the outermost cellular layer that separates the body from the gut lumen. The integrity of this protective mucosal barrier is crucial and maintained by specialized cells-intraepithelial lymphocytes (IEL). Much research has been conducted on these cells and our overall understanding of them is increasing rapidly. In this review we focus on the TCRαβ+ subset of CD8αα IEL. We discuss recent studies that shed light on the development, ontogeny, maintenance, and functional characteristics of CD8αα IEL, and highlight yet unanswered questions for future studies.
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Affiliation(s)
- Roland Ruscher
- Center for Immunology and Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN, USA
| | - Kristin A Hogquist
- Center for Immunology and Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN, USA.
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5
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Abdel-Gadir A, Massoud AH, Chatila TA. Antigen-specific Treg cells in immunological tolerance: implications for allergic diseases. F1000Res 2018; 7:38. [PMID: 29375821 PMCID: PMC5765398 DOI: 10.12688/f1000research.12650.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/08/2018] [Indexed: 02/06/2023] Open
Abstract
Allergic diseases are chronic inflammatory disorders in which there is failure to mount effective tolerogenic immune responses to inciting allergens. The alarming rise in the prevalence of allergic diseases in recent decades has spurred investigations to elucidate the mechanisms of breakdown in tolerance in these disorders and means of restoring it. Tolerance to allergens is critically dependent on the generation of allergen-specific regulatory T (Treg) cells, which mediate a state of sustained non-responsiveness to the offending allergen. In this review, we summarize recent advances in our understanding of mechanisms governing the generation and function of allergen-specific Treg cells and their subversion in allergic diseases. We will also outline approaches to harness allergen-specific Treg cell responses to restore tolerance in these disorders.
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Affiliation(s)
- Azza Abdel-Gadir
- Division of Immunology, Boston Children's Hospital, Boston, USA.,Department of Pediatrics, Harvard Medical School, Boston, USA
| | - Amir H Massoud
- Division of Immunology, Boston Children's Hospital, Boston, USA.,Department of Pediatrics, Harvard Medical School, Boston, USA
| | - Talal A Chatila
- Division of Immunology, Boston Children's Hospital, Boston, USA.,Department of Pediatrics, Harvard Medical School, Boston, USA
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6
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Best K, Chain B, Watkins C. Immune Tolerance Maintained by Cooperative Interactions between T Cells and Antigen Presenting Cells Shapes a Diverse TCR Repertoire. Front Immunol 2015; 6:360. [PMID: 26300880 PMCID: PMC4528093 DOI: 10.3389/fimmu.2015.00360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 07/02/2015] [Indexed: 11/17/2022] Open
Abstract
The T cell population in an individual needs to avoid harmful activation by self peptides while maintaining the ability to respond to an unknown set of foreign peptides. This property is acquired by a combination of thymic and extra-thymic mechanisms. We extend current models for the development of self/non-self discrimination to consider the acquisition of self-tolerance as an emergent system level property of the overall T cell receptor repertoire. We propose that tolerance is established at the level of the antigen presenting cell/T cell cluster, which facilitates and integrates cooperative interactions between T cells of different specificities. The threshold for self-reactivity is therefore imposed at a population level, and not at the level of the individual T cell/antigen encounter. Mathematically, the model can be formulated as a linear programing optimization problem that can be implemented as a multiplicative update algorithm, which shows a rapid convergence to a stable state. The model constrains self-reactivity within a predefined threshold, but maintains repertoire diversity and cross reactivity which are key characteristics of human T cell immunity. We show further that the size of individual clones in the model repertoire becomes heterogeneous, and that new clones can establish themselves even when the repertoire has stabilized. Our study combines the salient features of the “danger” model of self/non-self discrimination with the concepts of quorum sensing, and extends repertoire generation models to encompass the establishment of tolerance. Furthermore, the dynamic and continuous repertoire reshaping, which underlies tolerance in this model, suggests opportunities for therapeutic intervention to achieve long-term tolerance following transplantation.
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Affiliation(s)
- Katharine Best
- Division of Infection and Immunity, University College London , London , UK ; Centre for Mathematics, Physics and Engineering in the Life Sciences and Experimental Biology (CoMPLEX), University College London , London , UK
| | - Benny Chain
- Division of Infection and Immunity, University College London , London , UK
| | - Chris Watkins
- Department of Computer Science, Royal Holloway, University of London , London , UK
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7
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Leyva-Rangel JP, de Los Angeles Hernández-Cueto M, Galan-Enriquez CS, López-Medina M, Ortiz-Navarrete V. Bacterial clearance reverses a skewed T-cell repertoire induced by Salmonella infection. IMMUNITY INFLAMMATION AND DISEASE 2015; 3:209-23. [PMID: 26417438 PMCID: PMC4578521 DOI: 10.1002/iid3.60] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/25/2015] [Accepted: 03/27/2015] [Indexed: 11/06/2022]
Abstract
Salmonella typhimurium invades the spleen, liver, and peripheral lymph nodes and has recently been detected in the bone marrow and thymus, resulting in a reduced thymic size and a decline in the total number of thymic cells. A specific deletion of the double-positive cell subset has been characterized, yet the export of mature T cells to the periphery remains normal. We analyzed Salmonella pathogenesis regarding thymic structure and the T-cell maturation process. We demonstrate that, despite alterations in the thymic structure, T-cell development is maintained during Salmonella infection, allowing the selection of single-positive T-cell clones expressing particular T-cell receptor beta chains (TCR-Vβ). Moreover, the treatment of infected mice with an antibiotic restored the normal thymic architecture and thymocyte subset distribution. Additionally, the frequency of TCR-Vβ usage after treatment was comparable to that in non-infected mice. However, bacteria were still recovered from the thymus after 1 month of treatment. Our data reveal that a skewed T-cell developmental process is present in the Salmonella-infected thymus that alters the TCR-Vβ usage frequency. Likewise, the post-treatment persistence of Salmonella reveals a novel function of the thymus as a potential reservoir for this infectious agent.
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Affiliation(s)
- Jessica P Leyva-Rangel
- Doctorado en Ciencias Biomédicas Facultad de Medicina, UNAM Mexico City, CP 045510, Mexico ; Departamento de Biomedicina Molecular, Centro de Investigación y Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV) Mexico City
| | | | - Carlos-Samuel Galan-Enriquez
- Departamento de Biomedicina Molecular, Centro de Investigación y Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV) Mexico City
| | - Marcela López-Medina
- Departamento de Biomedicina Molecular, Centro de Investigación y Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV) Mexico City
| | - Vianney Ortiz-Navarrete
- Departamento de Biomedicina Molecular, Centro de Investigación y Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV) Mexico City
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Khailaie S, Robert PA, Toker A, Huehn J, Meyer-Hermann M. A signal integration model of thymic selection and natural regulatory T cell commitment. THE JOURNAL OF IMMUNOLOGY 2014; 193:5983-96. [PMID: 25392533 DOI: 10.4049/jimmunol.1400889] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The extent of TCR self-reactivity is the basis for selection of a functional and self-tolerant T cell repertoire and is quantified by repeated engagement of TCRs with a diverse pool of self-peptides complexed with self-MHC molecules. The strength of a TCR signal depends on the binding properties of a TCR to the peptide and the MHC, but it is not clear how the specificity to both components drives fate decisions. In this study, we propose a TCR signal-integration model of thymic selection that describes how thymocytes decide among distinct fates, not only based on a single TCR-ligand interaction, but taking into account the TCR stimulation history. These fates are separated based on sustained accumulated signals for positive selection and transient peak signals for negative selection. This spans up the cells into a two-dimensional space where they are either neglected, positively selected, negatively selected, or selected as natural regulatory T cells (nTregs). We show that the dynamics of the integrated signal can serve as a successful basis for extracting specificity of thymocytes to MHC and detecting the existence of cognate self-peptide-MHC. It allows to select a self-MHC-biased and self-peptide-tolerant T cell repertoire. Furthermore, nTregs in the model are enriched with MHC-specific TCRs. This allows nTregs to be more sensitive to activation and more cross-reactive than conventional T cells. This study provides a mechanistic model showing that time integration of TCR-mediated signals, as opposed to single-cell interaction events, is needed to gain a full view on the properties emerging from thymic selection.
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Affiliation(s)
- Sahamoddin Khailaie
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Philippe A Robert
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; Institut de Génétique Moléculaire de Montpellier, Centre National de la Recherche Scientifique, 34293 Montpellier, France
| | - Aras Toker
- Department of Experimental Immunology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; and
| | - Jochen Huehn
- Department of Experimental Immunology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; and
| | - Michael Meyer-Hermann
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; Institute for Biochemistry, Biotechnology, and Bioinformatics, University of Technology Braunschweig, 38106 Braunschweig, Germany
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9
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Lymphocyte repertoire selection and intracellular self/non-self-discrimination: historical overview. Immunol Cell Biol 2014; 93:297-304. [PMID: 25385066 DOI: 10.1038/icb.2014.96] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 09/19/2014] [Accepted: 10/15/2014] [Indexed: 02/07/2023]
Abstract
Immunological self/non-self-discrimination is conventionally seen as an extracellular event, involving interactions been receptors on T cells pre-educated to discriminate and peptides bound to major histocompatibility complex proteins (pMHCs). Mechanisms by which non-self peptides might first be sorted intracellularly to distinguish them from the vast excess of self-peptides have long been called for. Recent demonstrations of endogenous peptide-specific clustering of pMHCs on membrane rafts are indicative of intracellular enrichment before surface display. The clustering could follow the specific aggregation of a foreign protein that exceeded its solubility limit in the crowded intracellular environment. Predominantly entropy-driven, this homoaggregation would colocalize identical peptides, thus facilitating their collective presentation. Concentrations of self-proteins are fine-tuned over evolutionary time to avoid this. Disparate observations, such as pyrexia and female susceptibility to autoimmune disease, can be explained in terms of the need to cosegregate cognate pMHC complexes internally before extracellular display.
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10
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Marshall D, Sinclair C, Tung S, Seddon B. Differential requirement for IL-2 and IL-15 during bifurcated development of thymic regulatory T cells. THE JOURNAL OF IMMUNOLOGY 2014; 193:5525-33. [PMID: 25348623 DOI: 10.4049/jimmunol.1402144] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The developmental pathways of regulatory T cells (T(reg)) generation in the thymus are not fully understood. In this study, we reconstituted thymic development of Zap70-deficient thymocytes with a tetracycline-inducible Zap70 transgene to allow temporal dissection of T(reg) development. We find that T(reg) develop with distinctive kinetics, first appearing by day 4 among CD4 single-positive (SP) thymocytes. Accepted models of CD25(+)Foxp3(+) T(reg) selection suggest development via CD25(+)Foxp3(-) CD4 SP precursors. In contrast, our kinetic analysis revealed the presence of abundant CD25(-)Foxp3(+) cells that are highly efficient at maturing to CD25(+)Foxp3(+) cells in response to IL-2. CD25(-)Foxp3(+) cells more closely resembled mature T(reg) both with respect to kinetics of development and avidity for self-peptide MHC. These population also exhibited distinct requirements for cytokines during their development. CD25(-)Foxp3(+) cells were IL-15 dependent, whereas generation of CD25(+)Foxp3(+) specifically required IL-2. Finally, we found that IL-2 and IL-15 arose from distinct sources in vivo. IL-15 was of stromal origin, whereas IL-2 was of exclusively from hemopoetic cells that depended on intact CD4 lineage development but not either Ag-experienced or NKT cells.
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Affiliation(s)
- Daniel Marshall
- Division of Immune Cell Biology, Medical Research Council National Institute for Medical Research, London, NW7 1AA, United Kingdom
| | - Charles Sinclair
- Division of Immune Cell Biology, Medical Research Council National Institute for Medical Research, London, NW7 1AA, United Kingdom
| | - Sim Tung
- Division of Immune Cell Biology, Medical Research Council National Institute for Medical Research, London, NW7 1AA, United Kingdom
| | - Benedict Seddon
- Division of Immune Cell Biology, Medical Research Council National Institute for Medical Research, London, NW7 1AA, United Kingdom
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11
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The same self-peptide selects conventional and regulatory CD4⁺ T cells with identical antigen receptors. Nat Commun 2014; 5:5061. [PMID: 25270305 PMCID: PMC4183978 DOI: 10.1038/ncomms6061] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 08/25/2014] [Indexed: 12/28/2022] Open
Abstract
The role of the T cell receptor (TCR) in commitment of thymocytes to regulatory CD4+Foxp3+ and conventional CD4−Foxp3− T cell lineages remains controversial. According to the prevailing view, commitment to the former lineage, in contrast to the latter, requires that high affinity TCRs bind rare class II MHC/peptide complexes presented in “thymic niches”, which could explain differences between their TCR repertoires. Here we challenge this view and show that the binding of identical TCRs to the same ubiquitously expressed MHC/peptide complex often directs thymocytes to both CD4+ lineages, indicating that the TCR affinity does not play the instructive role, and that restricted presentation of peptides in ”thymic niches” is not necessary for selection of CD4+Foxp3+ T cells. However, depending on whether immature thymocytes bound the ligand predominantly with low or high affinity, the repertoires of regulatory and conventional CD4+ T cells were correspondingly similar or mostly different, suggesting that negative rather than positive selection sets them apart.
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12
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Hogquist KA, Jameson SC. The self-obsession of T cells: how TCR signaling thresholds affect fate 'decisions' and effector function. Nat Immunol 2014; 15:815-23. [PMID: 25137456 PMCID: PMC4348363 DOI: 10.1038/ni.2938] [Citation(s) in RCA: 196] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 06/02/2014] [Indexed: 12/11/2022]
Abstract
Self-reactivity was once seen as a potential characteristic of T cells that was eliminated by clonal selection to protect the host from autoimmune pathology. It is now understood that the T cell repertoire is in fact broadly self-reactive, even self-centered. The strength with which a T cell reacts to self ligands and the environmental context in which this reaction occurs influence almost every aspect of T cell biology, from development to differentiation to effector function. Here we highlight recent advances and discoveries that relate to T cell self-reactivity, with a particular emphasis on T cell antigen receptor (TCR) signaling thresholds.
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Affiliation(s)
- Kristin A Hogquist
- Center for Immunology and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Stephen C Jameson
- Center for Immunology and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota, USA
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13
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Klein L, Kyewski B, Allen PM, Hogquist KA. Positive and negative selection of the T cell repertoire: what thymocytes see (and don't see). Nat Rev Immunol 2014; 14:377-91. [PMID: 24830344 PMCID: PMC4757912 DOI: 10.1038/nri3667] [Citation(s) in RCA: 889] [Impact Index Per Article: 88.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The fate of developing T cells is specified by the interaction of their antigen receptors with self-peptide-MHC complexes that are displayed by thymic antigen-presenting cells (APCs). Various subsets of thymic APCs are strategically positioned in particular thymic microenvironments and they coordinate the selection of a functional and self-tolerant T cell repertoire. In this Review, we discuss the different strategies that these APCs use to sample and process self antigens and to thereby generate partly unique, 'idiosyncratic' peptide-MHC ligandomes. We discuss how the particular composition of the peptide-MHC ligandomes that are presented by specific APC subsets not only shapes the T cell repertoire in the thymus but may also indelibly imprint the behaviour of mature T cells in the periphery.
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Affiliation(s)
- Ludger Klein
- Institute for Immunology, Ludwig Maximilians University, 80336 Munich, Germany
| | - Bruno Kyewski
- Division of Developmental Immunology, German Cancer Research Center, 69120 Heidelberg, Germany
| | - Paul M Allen
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Kristin A Hogquist
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota 55414, USA
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14
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Abstract
The peripheral T cell repertoire is sculpted from prototypic T cells in the thymus bearing randomly generated T cell receptors (TCR) and by a series of developmental and selection steps that remove cells that are unresponsive or overly reactive to self-peptide–MHC complexes. The challenge of understanding how the kinetics of T cell development and the statistics of the selection processes combine to provide a diverse but self-tolerant T cell repertoire has invited quantitative modeling approaches, which are reviewed here.
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Affiliation(s)
- Andrew J Yates
- Departments of Systems and Computational Biology, Microbiology and Immunology, Albert Einstein College of Medicine , New York, NY , USA
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