1
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T-cell Receptor Is a Threshold Detector: Sub- and Supra-Threshold Stochastic Resonance in TCR-MHC Clusters on the Cell Surface. ENTROPY 2022; 24:e24030389. [PMID: 35327900 PMCID: PMC8946872 DOI: 10.3390/e24030389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/02/2022] [Accepted: 03/05/2022] [Indexed: 12/13/2022]
Abstract
Stochastic resonance in clusters of major histocompatibility molecules is extended by a more detailed description of adaptive thresholding and by applying the notion of suprathreshold stochastic resonance as a stochastically quantizing encoder of transmembrane signaling downstream of major histocompatibility molecules and T-cell receptors on the side of presenting and recognizing cells, respectively. The adaptive nature of thresholding is partly explained by a mirroring of the noncognate–cognate dichotomy shown by the T-cell receptor structure and the kinetic-segregation model of the onset of T-cell receptor triggering. Membrane clusters of major histocompatibility molecules and T-cell receptors on their host cells are envisioned as places of the temporal encoding of downstream signals via the suprathreshold stochastic resonance process. The ways of optimization of molecular prostheses, such as chimeric antigen receptors against cancer in transmembrane signaling, are suggested in the framework of suprathreshold stochastic resonance. The analogy between Förster resonance energy transfer and suprathreshold stochastic resonance for information transfer is also discussed. The overlap integral for energy transfer parallels the mutual information transferred by suprathreshold stochastic resonance.
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2
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Dephosphorylation accelerates the dissociation of ZAP70 from the T cell receptor. Proc Natl Acad Sci U S A 2022; 119:2116815119. [PMID: 35197288 PMCID: PMC8892339 DOI: 10.1073/pnas.2116815119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2021] [Indexed: 11/20/2022] Open
Abstract
Src homology 2 (SH2) domains are phosphotyrosine binding motifs that play key roles in cellular signaling. There are 110 proteins in the human genome containing SH2 binding domains, of which 10 contain tandem SH2 domains. Tandem domains have been shown to improve avidity and specificity and contribute to allostery. Here, we show that tandem SH2 domains can also exhibit binding lifetimes that are accelerated by the activity of phosphatases. This accelerated unbinding requires tandem SH2 domains to engage their substrates in dynamic binding modes that cycle between single SH2-bound states. We experimentally confirm that this is the case for the well-studied kinase ZAP70 binding the T cell receptor. We suggest that accelerated unbinding is a general feature of signaling networks. Protein–protein binding domains are critical in signaling networks. Src homology 2 (SH2) domains are binding domains that interact with sequences containing phosphorylated tyrosines. A subset of SH2 domain–containing proteins has tandem domains, which are thought to enhance binding affinity and specificity. However, a trade-off exists between long-lived binding and the ability to rapidly reverse signaling, which is a critical requirement of noise-filtering mechanisms such as kinetic proofreading. Here, we use modeling to show that the unbinding rate of tandem, but not single, SH2 domains can be accelerated by phosphatases. Using surface plasmon resonance, we show that the phosphatase CD45 can accelerate the unbinding rate of zeta chain–associated protein kinase 70 (ZAP70), a tandem SH2 domain–containing kinase, from biphosphorylated peptides from the T cell receptor (TCR). An important functional prediction of accelerated unbinding is that the intracellular ZAP70–TCR half-life in T cells will not be fixed but rather, dependent on the extracellular TCR–antigen half-life, and we show that this is the case in both cell lines and primary T cells. The work highlights that tandem SH2 domains can break the trade-off between signal fidelity (requiring long half-life) and signal reversibility (requiring short half-life), which is a key requirement for T cell antigen discrimination mediated by kinetic proofreading.
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3
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Staggered starts in the race to T cell activation. Trends Immunol 2021; 42:994-1008. [PMID: 34649777 PMCID: PMC7612485 DOI: 10.1016/j.it.2021.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/12/2021] [Accepted: 09/13/2021] [Indexed: 02/07/2023]
Abstract
How T lymphocytes tune their responses to different strengths of stimulation is a fundamental question in immunology. Recent work using new optogenetic, single-cell genomic, and live-imaging approaches has revealed that stimulation strength controls the rate of individual cell responses within a population. Moreover, these responses have been found to use shared molecular programs, regardless of stimulation strength. However, additional data indicate that stimulation duration or cytokine feedback can impact later gene expression phenotypes of activated cells. In-depth molecular studies have suggested mechanisms by which stimulation strength might modulate the probability of T cell activation. This emerging model allows activating T cells to achieve a wide range of population responses through probabilistic control within individual cells.
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4
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CD8 coreceptor-mediated focusing can reorder the agonist hierarchy of peptide ligands recognized via the T cell receptor. Proc Natl Acad Sci U S A 2021; 118:2019639118. [PMID: 34272276 PMCID: PMC8307375 DOI: 10.1073/pnas.2019639118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
CD8+ T cells are inherently cross-reactive and recognize numerous peptide antigens in the context of a given major histocompatibility complex class I (MHCI) molecule via the clonotypically expressed T cell receptor (TCR). The lineally expressed coreceptor CD8 interacts coordinately with MHCI at a distinct and largely invariant site to slow the TCR/peptide-MHCI (pMHCI) dissociation rate and enhance antigen sensitivity. However, this biological effect is not necessarily uniform, and theoretical models suggest that antigen sensitivity can be modulated in a differential manner by CD8. We used two intrinsically controlled systems to determine how the relationship between the TCR/pMHCI interaction and the pMHCI/CD8 interaction affects the functional sensitivity of antigen recognition. Our data show that modulation of the pMHCI/CD8 interaction can reorder the agonist hierarchy of peptide ligands across a spectrum of affinities for the TCR.
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5
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Holland CJ, Crean RM, Pentier JM, de Wet B, Lloyd A, Srikannathasan V, Lissin N, Lloyd KA, Blicher TH, Conroy PJ, Hock M, Pengelly RJ, Spinner TE, Cameron B, Potter EA, Jeyanthan A, Molloy PE, Sami M, Aleksic M, Liddy N, Robinson RA, Harper S, Lepore M, Pudney CR, van der Kamp MW, Rizkallah PJ, Jakobsen BK, Vuidepot A, Cole DK. Specificity of bispecific T cell receptors and antibodies targeting peptide-HLA. J Clin Invest 2021; 130:2673-2688. [PMID: 32310221 DOI: 10.1172/jci130562] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 02/11/2020] [Indexed: 01/09/2023] Open
Abstract
Tumor-associated peptide-human leukocyte antigen complexes (pHLAs) represent the largest pool of cell surface-expressed cancer-specific epitopes, making them attractive targets for cancer therapies. Soluble bispecific molecules that incorporate an anti-CD3 effector function are being developed to redirect T cells against these targets using 2 different approaches. The first achieves pHLA recognition via affinity-enhanced versions of natural TCRs (e.g., immune-mobilizing monoclonal T cell receptors against cancer [ImmTAC] molecules), whereas the second harnesses an antibody-based format (TCR-mimic antibodies). For both classes of reagent, target specificity is vital, considering the vast universe of potential pHLA molecules that can be presented on healthy cells. Here, we made use of structural, biochemical, and computational approaches to investigate the molecular rules underpinning the reactivity patterns of pHLA-targeting bispecifics. We demonstrate that affinity-enhanced TCRs engage pHLA using a comparatively broad and balanced energetic footprint, with interactions distributed over several HLA and peptide side chains. As ImmTAC molecules, these TCRs also retained a greater degree of pHLA selectivity, with less off-target activity in cellular assays. Conversely, TCR-mimic antibodies tended to exhibit binding modes focused more toward hot spots on the HLA surface and exhibited a greater degree of crossreactivity. Our findings extend our understanding of the basic principles that underpin pHLA selectivity and exemplify a number of molecular approaches that can be used to probe the specificity of pHLA-targeting molecules, aiding the development of future reagents.
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Affiliation(s)
| | - Rory M Crean
- Department of Biology and Biochemistry and.,Doctoral Training Centre in Sustainable Chemical Technologies, University of Bath, Bath, United Kingdom
| | | | - Ben de Wet
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | | | - Katy A Lloyd
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | - Paul J Conroy
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | - Miriam Hock
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | - Brian Cameron
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | | | - Malkit Sami
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | - Milos Aleksic
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | | | - Marco Lepore
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | - Pierre J Rizkallah
- Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | | | | | - David K Cole
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom.,Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
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6
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Lee CH, Salio M, Napolitani G, Ogg G, Simmons A, Koohy H. Predicting Cross-Reactivity and Antigen Specificity of T Cell Receptors. Front Immunol 2020; 11:565096. [PMID: 33193332 PMCID: PMC7642207 DOI: 10.3389/fimmu.2020.565096] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 09/07/2020] [Indexed: 12/13/2022] Open
Abstract
Adaptive immune recognition is mediated by specific interactions between heterodimeric T cell receptors (TCRs) and their cognate peptide-MHC (pMHC) ligands, and the methods to accurately predict TCR:pMHC interaction would have profound clinical, therapeutic and pharmaceutical applications. Herein, we review recent developments in predicting cross-reactivity and antigen specificity of TCR recognition. We discuss current experimental and computational approaches to investigate cross-reactivity and antigen-specificity of TCRs and highlight how integrating kinetic, biophysical and structural features may offer valuable insights in modeling immunogenicity. We further underscore the close inter-relationship of these two interconnected notions and the need to investigate each in the light of the other for a better understanding of T cell responsiveness for the effective clinical applications.
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Affiliation(s)
- Chloe H. Lee
- MRC Human Immunology Unit, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine (WIMM), John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- MRC WIMM Centre for Computational Biology, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Mariolina Salio
- MRC Human Immunology Unit, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine (WIMM), John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Giorgio Napolitani
- MRC Human Immunology Unit, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine (WIMM), John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Graham Ogg
- MRC Human Immunology Unit, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine (WIMM), John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Alison Simmons
- MRC Human Immunology Unit, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine (WIMM), John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- Translational Gastroenterology Unit, John Radcliffe Hospital, Oxford, United Kingdom
| | - Hashem Koohy
- MRC Human Immunology Unit, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine (WIMM), John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- MRC WIMM Centre for Computational Biology, Medical Research Council (MRC) Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
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7
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Abu-Shah E, Trendel N, Kruger P, Nguyen J, Pettmann J, Kutuzov M, Dushek O. Human CD8 + T Cells Exhibit a Shared Antigen Threshold for Different Effector Responses. THE JOURNAL OF IMMUNOLOGY 2020; 205:1503-1512. [PMID: 32817332 PMCID: PMC7477745 DOI: 10.4049/jimmunol.2000525] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/21/2020] [Indexed: 12/21/2022]
Abstract
CD8+ T cells produce TNF-α, IL-2, and IFN-γ with similar Ag thresholds. Costimulation decreases Ag thresholds similarly for different cytokines. A common rate-limiting switch downstream of the TCR can explain these findings.
T cells recognizing cognate pMHC Ags become activated to elicit a myriad of cellular responses, such as target cell killing and the secretion of different cytokines, that collectively contribute to adaptive immunity. These effector responses have been hypothesized to exhibit different Ag dose and affinity thresholds, suggesting that pathogen-specific information may be encoded within the nature of the Ag. In this study, using systematic experiments in a reductionist system, in which primary human CD8+ T cell blasts are stimulated by recombinant peptides presented on MHC Ag alone, we show that different inflammatory cytokines have comparable Ag dose thresholds across a 25,000-fold variation in affinity. Although costimulation by CD28, CD2, and CD27 increased cytokine production in this system, the Ag threshold remained comparable across different cytokines. When using primary human memory CD8+ T cells responding to autologous APCs, equivalent thresholds were also observed for different cytokines and killing. These findings imply a simple phenotypic model of TCR signaling in which multiple T cell responses share a common rate-limiting threshold and a conceptually simple model of CD8+ T cell Ag recognition, in which Ag dose and affinity do not provide any additional response-specific information.
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Affiliation(s)
- Enas Abu-Shah
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; and.,Kennedy Institute of Rheumatology, University of Oxford, Oxford OX3 7FY, United Kingdom
| | - Nicola Trendel
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; and
| | - Philipp Kruger
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; and
| | - John Nguyen
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; and
| | - Johannes Pettmann
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; and
| | - Mikhail Kutuzov
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; and
| | - Omer Dushek
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom; and
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8
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Meryk A, Pangrazzi L, Hagen M, Hatzmann F, Jenewein B, Jakic B, Hermann-Kleiter N, Baier G, Jylhävä J, Hurme M, Trieb K, Grubeck-Loebenstein B. Fcμ receptor as a Costimulatory Molecule for T Cells. Cell Rep 2020; 26:2681-2691.e5. [PMID: 30840890 DOI: 10.1016/j.celrep.2019.02.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 01/28/2019] [Accepted: 02/07/2019] [Indexed: 11/17/2022] Open
Abstract
Fc receptor for IgM (FcμR)-deficient mice display dysregulated function of neutrophils, dendritic cells, and B cells. The relevance of FcμR to human T cells is still unknown. We show that FcμR is mostly stored inside the cell and that surface expression is tightly regulated. Decreased surface expression on T cells from elderly individuals is associated with alterations in the methylation pattern of the FCMR gene. Binding and internalization of IgM stimulate transport of FcμR to the cell surface to ensure sustained IgM uptake. Concurrently, IgM accumulates within the cell, and the surface expression of other receptors increases, among them the T cell receptor (TCR) and costimulatory molecules. This leads to enhanced TCR signaling, proliferation, and cytokine release, in response to low, but not high, doses of antigen. Our findings indicate that FcμR is an important regulator of T cell function and reveal an additional mode of interaction between B and T cells.
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Affiliation(s)
- Andreas Meryk
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, 6020 Innsbruck, Austria.
| | - Luca Pangrazzi
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, 6020 Innsbruck, Austria
| | - Magdalena Hagen
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, 6020 Innsbruck, Austria
| | - Florian Hatzmann
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, 6020 Innsbruck, Austria
| | - Brigitte Jenewein
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, 6020 Innsbruck, Austria
| | - Bojana Jakic
- Division of Translational Cell Genetics, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Natascha Hermann-Kleiter
- Division of Translational Cell Genetics, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Gottfried Baier
- Division of Translational Cell Genetics, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Juulia Jylhävä
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, 17177 Stockholm, Sweden
| | - Mikko Hurme
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere 33014, Finland
| | - Klemens Trieb
- Department of Orthopedic Surgery, Hospital Wels-Grieskirchen, 4600 Wels, Austria
| | - Beatrix Grubeck-Loebenstein
- Department of Immunology, Institute for Biomedical Aging Research, University of Innsbruck, 6020 Innsbruck, Austria
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9
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Venturi V, Thomas PG. The expanding role of systems immunology in decoding the T cell receptor repertoire. ACTA ACUST UNITED AC 2018; 12:37-45. [PMID: 31106281 DOI: 10.1016/j.coisb.2018.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
T cells play a crucial role in the immune system's defense against many infectious diseases, including persistent infections for which no effective vaccines currently exist. The T cell component of the adaptive immune system is highly complex involving a constantly evolving landscape of various inter-related T cell populations. These T cell populations are characterized by their phenotypic and functional properties as well as the collection, or repertoire, of T cell receptors (TCR) that mediate T cell recognition of antigenic peptides derived from pathogens. Understanding the various processes and factors that impact the development and evolution of the broader T cell repertoire available to recognize and respond to pathogens and the characteristics of antigen-experienced T cell repertoires associated with effective immune control of pathogens is critical to the rational design of T cell-based vaccines and therapies. In this article we discuss, using examples of recent research, the promise that systems immunology approaches, involving quantitative analysis and mathematical and computational modeling of immunological data, hold for decoding the complex TCR repertoire system in the current era of advancing technologies.
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Affiliation(s)
- Vanessa Venturi
- Infection Analytics Program, Kirby Institute for Infection and Immunity, UNSW Australia, Sydney, NSW, Australia
| | - Paul G Thomas
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
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10
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Miles JJ, Tan MP, Dolton G, Edwards ES, Galloway SA, Laugel B, Clement M, Makinde J, Ladell K, Matthews KK, Watkins TS, Tungatt K, Wong Y, Lee HS, Clark RJ, Pentier JM, Attaf M, Lissina A, Ager A, Gallimore A, Rizkallah PJ, Gras S, Rossjohn J, Burrows SR, Cole DK, Price DA, Sewell AK. Peptide mimic for influenza vaccination using nonnatural combinatorial chemistry. J Clin Invest 2018; 128:1569-1580. [PMID: 29528337 PMCID: PMC5873848 DOI: 10.1172/jci91512] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 01/18/2018] [Indexed: 01/11/2023] Open
Abstract
Polypeptide vaccines effectively activate human T cells but suffer from poor biological stability, which confines both transport logistics and in vivo therapeutic activity. Synthetic biology has the potential to address these limitations through the generation of highly stable antigenic "mimics" using subunits that do not exist in the natural world. We developed a platform based on D-amino acid combinatorial chemistry and used this platform to reverse engineer a fully artificial CD8+ T cell agonist that mirrored the immunogenicity profile of a native epitope blueprint from influenza virus. This nonnatural peptide was highly stable in human serum and gastric acid, reflecting an intrinsic resistance to physical and enzymatic degradation. In vitro, the synthetic agonist stimulated and expanded an archetypal repertoire of polyfunctional human influenza virus-specific CD8+ T cells. In vivo, specific responses were elicited in naive humanized mice by subcutaneous vaccination, conferring protection from subsequent lethal influenza challenge. Moreover, the synthetic agonist was immunogenic after oral administration. This proof-of-concept study highlights the power of synthetic biology to expand the horizons of vaccine design and therapeutic delivery.
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Affiliation(s)
- John J. Miles
- Centre for Biodiscovery and Molecular Development of Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
- School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
- Griffith University, Brisbane, Queensland, Australia
| | - Mai Ping Tan
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Garry Dolton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
- Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Emily S.J. Edwards
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Sarah A.E. Galloway
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Bruno Laugel
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Mathew Clement
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Julia Makinde
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Kristin Ladell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
- Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
| | | | - Thomas S. Watkins
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Katie Tungatt
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Yide Wong
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Han Siean Lee
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Richard J. Clark
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Johanne M. Pentier
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Meriem Attaf
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Anya Lissina
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Ann Ager
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Awen Gallimore
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Pierre J. Rizkallah
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Stephanie Gras
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, and
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia
| | - Jamie Rossjohn
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, and
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia
| | - Scott R. Burrows
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - David K. Cole
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - David A. Price
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
- Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Andrew K. Sewell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
- Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
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11
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Han C, Sim SJ, Kim SH, Singh R, Hwang S, Kim YI, Park SH, Kim KH, Lee DG, Oh HS, Lee S, Kim YH, Choi BK, Kwon BS. Desensitized chimeric antigen receptor T cells selectively recognize target cells with enhanced antigen expression. Nat Commun 2018; 9:468. [PMID: 29391449 PMCID: PMC5794762 DOI: 10.1038/s41467-018-02912-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 01/09/2018] [Indexed: 12/30/2022] Open
Abstract
Chimeric antigen receptor (CAR) T cell therapy is an effective method for treating specific cancers. CARs are normally designed to recognize antigens, which are highly expressed on malignant cells but not on T cells. However, when T cells are engineered with CARs that recognize antigens expressed on the T cell surface, CAR T cells exhibit effector function on other T cells, which results in fratricide, or killing of neighboring T cells. Here, using human leukocyte antigen-DR (HLA-DR)-targeted CAR T cells, we show that weak affinity between CAR and HLA-DR reduces fratricide and induces sustained CAR downregulation, which consequently tunes the avidity of CAR T cells, leading to desensitization. We further demonstrate that desensitized CAR T cells selectively kill Epstein-Barr virus-transformed B cells with enhanced HLA-DR expression, while sparing normal B cells. Our study supports an avidity-tuning strategy that permits sensing of antigen levels by CAR T cells. Engineered T cells with chimeric antigen receptor (CAR) are emerging as an effective cancer therapy. Here the authors show that CAR T cells recognizing self-MHC can be ‘tuned’ ex vivo via CAR downregulation and CAR T cell death to generate a CAR T pool specifically targeting tumor cells with high MHC expression.
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Affiliation(s)
- Chungyong Han
- Immunotherapeutics Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Su-Jung Sim
- Immunotherapeutics Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Seon-Hee Kim
- Immunotherapeutics Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Rohit Singh
- Immunotherapeutics Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Sunhee Hwang
- Eutilex Institute for Biomedical Research, Eutilex Co., Ltd., Seoul, 08594, Republic of Korea
| | - Yu I Kim
- Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Sang H Park
- Immunotherapeutics Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Kwang H Kim
- Immunotherapeutics Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Don G Lee
- Biomedicine Production Branch, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Ho S Oh
- Eutilex Institute for Biomedical Research, Eutilex Co., Ltd., Seoul, 08594, Republic of Korea
| | - Sangeun Lee
- Immunotherapeutics Branch, Division of Convergence Technology, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Young H Kim
- Eutilex Institute for Biomedical Research, Eutilex Co., Ltd., Seoul, 08594, Republic of Korea.,Biomedicine Production Branch, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Beom K Choi
- Biomedicine Production Branch, Research Institute, National Cancer Center, Goyang, 10408, Republic of Korea
| | - Byoung S Kwon
- Eutilex Institute for Biomedical Research, Eutilex Co., Ltd., Seoul, 08594, Republic of Korea. .,Department of Medicine, Tulane University Health Sciences Center, New Orleans, LA, 70118, USA.
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12
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Kurioka A, Jahun AS, Hannaway RF, Walker LJ, Fergusson JR, Sverremark-Ekström E, Corbett AJ, Ussher JE, Willberg CB, Klenerman P. Shared and Distinct Phenotypes and Functions of Human CD161++ Vα7.2+ T Cell Subsets. Front Immunol 2017; 8:1031. [PMID: 28912775 PMCID: PMC5582200 DOI: 10.3389/fimmu.2017.01031] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 08/09/2017] [Indexed: 01/03/2023] Open
Abstract
Human mucosal-associated invariant T (MAIT) cells are an important T cell subset that are enriched in tissues and possess potent effector functions. Typically such cells are marked by their expression of Vα7.2-Jα33/Jα20/Jα12 T cell receptors, and functionally they are major histocompatibility complex class I-related protein 1 (MR1)-restricted, responding to bacterially derived riboflavin synthesis intermediates. MAIT cells are contained within the CD161++ Vα7.2+ T cell population, the majority of which express the CD8 receptor (CD8+), while a smaller fraction expresses neither CD8 or CD4 coreceptor (double negative; DN) and a further minority are CD4+. Whether these cells have distinct homing patterns, phenotype and functions have not been examined in detail. We used a combination of phenotypic staining and functional assays to address the similarities and differences between these CD161++ Vα7.2+ T cell subsets. We find that most features are shared between CD8+ and DN CD161++ Vα7.2+ T cells, with a small but detectable role evident for CD8 binding in tuning functional responsiveness. By contrast, the CD4+ CD161++ Vα7.2+ T cell population, although showing MR1-dependent responsiveness to bacterial stimuli, display reduced T helper 1 effector functions, including cytolytic machinery, while retaining the capacity to secrete interleukin-4 (IL-4) and IL-13. This was consistent with underlying changes in transcription factor (TF) expression. Although we found that only a proportion of CD4+ CD161++ Vα7.2+ T cells stained for the MR1-tetramer, explaining some of the heterogeneity of CD4+ CD161++ Vα7.2+ T cells, these differences in TF expression were shared with CD4+ CD161++ MR1-tetramer+ cells. These data reveal the functional diversity of human CD161++ Vα7.2+ T cells and indicate potentially distinct roles for the different subsets in vivo.
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Affiliation(s)
- Ayako Kurioka
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
| | - Aminu S Jahun
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
| | - Rachel F Hannaway
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Lucy J Walker
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Joannah R Fergusson
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
| | - Eva Sverremark-Ekström
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Alexandra J Corbett
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
| | - James E Ussher
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Christian B Willberg
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom.,National Institute for Health Research Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - Paul Klenerman
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom.,National Institute for Health Research Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
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13
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Cole DK, van den Berg HA, Lloyd A, Crowther MD, Beck K, Ekeruche-Makinde J, Miles JJ, Bulek AM, Dolton G, Schauenburg AJ, Wall A, Fuller A, Clement M, Laugel B, Rizkallah PJ, Wooldridge L, Sewell AK. Structural Mechanism Underpinning Cross-reactivity of a CD8+ T-cell Clone That Recognizes a Peptide Derived from Human Telomerase Reverse Transcriptase. J Biol Chem 2016; 292:802-813. [PMID: 27903649 PMCID: PMC5247654 DOI: 10.1074/jbc.m116.741603] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 11/18/2016] [Indexed: 01/20/2023] Open
Abstract
T-cell cross-reactivity is essential for effective immune surveillance but has also been implicated as a pathway to autoimmunity. Previous studies have demonstrated that T-cell receptors (TCRs) that focus on a minimal motif within the peptide are able to facilitate a high level of T-cell cross-reactivity. However, the structural database shows that most TCRs exhibit less focused antigen binding involving contact with more peptide residues. To further explore the structural features that allow the clonally expressed TCR to functionally engage with multiple peptide-major histocompatibility complexes (pMHCs), we examined the ILA1 CD8+ T-cell clone that responds to a peptide sequence derived from human telomerase reverse transcriptase. The ILA1 TCR contacted its pMHC with a broad peptide binding footprint encompassing spatially distant peptide residues. Despite the lack of focused TCR-peptide binding, the ILA1 T-cell clone was still cross-reactive. Overall, the TCR-peptide contacts apparent in the structure correlated well with the level of degeneracy at different peptide positions. Thus, the ILA1 TCR was less tolerant of changes at peptide residues that were at, or adjacent to, key contact sites. This study provides new insights into the molecular mechanisms that control T-cell cross-reactivity with important implications for pathogen surveillance, autoimmunity, and transplant rejection.
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Affiliation(s)
- David K Cole
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom,
| | - Hugo A van den Berg
- the Mathematics Institute, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Angharad Lloyd
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Michael D Crowther
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Konrad Beck
- the Cardiff University School of Dentistry, Heath Park, Cardiff CF14 4XY, United Kingdom
| | - Julia Ekeruche-Makinde
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - John J Miles
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom.,the Queensland Institute of Medical Research Berghofer Medical Research Institute, Brisbane, Queensland 4029, Australia.,James Cook University, Cairns, Queensland 4870, Australia, and
| | - Anna M Bulek
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Garry Dolton
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Andrea J Schauenburg
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Aaron Wall
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Anna Fuller
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Mathew Clement
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Bruno Laugel
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Pierre J Rizkallah
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Linda Wooldridge
- the Faculty of Health Sciences, University of Bristol, Bristol BS8 1TD, United Kingdom
| | - Andrew K Sewell
- From the Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom,
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14
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Functional role of T-cell receptor nanoclusters in signal initiation and antigen discrimination. Proc Natl Acad Sci U S A 2016; 113:E5454-63. [PMID: 27573839 DOI: 10.1073/pnas.1607436113] [Citation(s) in RCA: 145] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Antigen recognition by the T-cell receptor (TCR) is a hallmark of the adaptive immune system. When the TCR engages a peptide bound to the restricting major histocompatibility complex molecule (pMHC), it transmits a signal via the associated CD3 complex. How the extracellular antigen recognition event leads to intracellular phosphorylation remains unclear. Here, we used single-molecule localization microscopy to quantify the organization of TCR-CD3 complexes into nanoscale clusters and to distinguish between triggered and nontriggered TCR-CD3 complexes. We found that only TCR-CD3 complexes in dense clusters were phosphorylated and associated with downstream signaling proteins, demonstrating that the molecular density within clusters dictates signal initiation. Moreover, both pMHC dose and TCR-pMHC affinity determined the density of TCR-CD3 clusters, which scaled with overall phosphorylation levels. Thus, TCR-CD3 clustering translates antigen recognition by the TCR into signal initiation by the CD3 complex, and the formation of dense signaling-competent clusters is a process of antigen discrimination.
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15
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Tan MP, Gerry AB, Brewer JE, Melchiori L, Bridgeman JS, Bennett AD, Pumphrey NJ, Jakobsen BK, Price DA, Ladell K, Sewell AK. T cell receptor binding affinity governs the functional profile of cancer-specific CD8+ T cells. Clin Exp Immunol 2015; 180:255-70. [PMID: 25496365 PMCID: PMC4408161 DOI: 10.1111/cei.12570] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2014] [Indexed: 12/17/2022] Open
Abstract
Antigen-specific T cell receptor (TCR) gene transfer via patient-derived T cells is an attractive approach to cancer therapy, with the potential to circumvent immune regulatory networks. However, high-affinity tumour-specific TCR clonotypes are typically deleted from the available repertoire during thymic selection because the vast majority of targeted epitopes are derived from autologous proteins. This process places intrinsic constraints on the efficacy of T cell-based cancer vaccines and therapeutic strategies that employ naturally generated tumour-specific TCRs. In this study, we used altered peptide ligands and lentivirus-mediated transduction of affinity-enhanced TCRs selected by phage display to study the functional properties of CD8(+) T cells specific for three different tumour-associated peptide antigens across a range of binding parameters. The key findings were: (i) TCR affinity controls T cell antigen sensitivity and polyfunctionality; (ii) supraphysiological affinity thresholds exist, above which T cell function cannot be improved; and (iii) T cells transduced with very high-affinity TCRs exhibit cross-reactivity with self-derived peptides presented by the restricting human leucocyte antigen. Optimal system-defined affinity windows above the range established for natural tumour-specific TCRs therefore allow the enhancement of T cell effector function without off-target effects. These findings have major implications for the rational design of novel TCR-based biologics underpinned by rigorous preclinical evaluation.
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Affiliation(s)
- M P Tan
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
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16
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Szomolay B, van den Berg HA. Modulation of T-cell receptor functional sensitivity via the opposing actions of protein tyrosine kinases and phosphatases: a mathematical model. Integr Biol (Camb) 2014; 6:1183-95. [PMID: 25310311 DOI: 10.1039/c4ib00190g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Combining receptor kinetics and stochastic modelling of receptor activation, we show that a T-cell can specifically augment its functional sensitivity to one particular peptide ligand while simultaneously decreasing its sensitivity to other ligands, by coordinating the expression levels of the co-receptor CD8 and the relative activities of kinases and phosphatases in the vicinity of the T-cell receptor (TCR). We propose that this focusable degeneracy of epitope recognition allows a TCR to have a wide range of potential ligands but be specifically sensitive to only one or a few of these at any one time, which resolves the paradox of how a relatively small number of clones (∼10(6)) can maintain the potential to respond to a vast space of ligands (∼20(9)) whilst avoiding auto-immunity. We validate the model against experimental data and predict shifts in functional sensitivity following a shift in the kinase/phosphatase balance (which could in principle be induced by experimental means). Moreover, we propose that in vivo, the T-cell gauges ligand quality by monitoring changes in TCR triggering rate concomitant with shifts in this balance, for instance as the immunological synapse matures.
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17
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18
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Tabbaa OP, Jayaprakash C. Mutual information and the fidelity of response of gene regulatory models. Phys Biol 2014; 11:046004. [DOI: 10.1088/1478-3975/11/4/046004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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19
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Laugel B. Bench, bedside, toolbox: T-cells deliver on every level. Front Immunol 2014; 5:31. [PMID: 24550915 PMCID: PMC3909921 DOI: 10.3389/fimmu.2014.00031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 01/19/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
- Bruno Laugel
- Institute of Infection and Immunity, Cardiff University School of Medicine , Cardiff , UK
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20
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Szomolay B, Williams T, Wooldridge L, van den Berg HA. Co-Receptor CD8-Mediated Modulation of T-Cell Receptor Functional Sensitivity and Epitope Recognition Degeneracy. Front Immunol 2013; 4:329. [PMID: 24151493 PMCID: PMC3801161 DOI: 10.3389/fimmu.2013.00329] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 09/27/2013] [Indexed: 11/18/2022] Open
Abstract
The interaction between T-cell receptors (TCRs) and peptide epitopes is highly degenerate: a TCR is capable of interacting productively with a wide range of different peptide ligands, involving not only cross-reactivity proper (similar epitopes elicit strong responses), but also polyspecificity (ligands with distinct physicochemical properties are capable of interacting with the TCR). Degeneracy does not gainsay the fact that TCR recognition is fundamentally specific: for the vast majority of ligands, the functional sensitivity of a given TCR is virtually null whereas this TCR has an appreciable functional sensitivity only for a minute fraction of all possible ligands. Degeneracy can be described mathematically as the probability that the functional sensitivity, of a given TCR to a randomly selected ligand, exceeds a set value. Variation of this value generates a statistical distribution that characterizes TCR degeneracy. This distribution can be modeled on the basis of a Gaussian distribution for the TCR/ligand dissociation energy. The kinetics of the TCR and the MHCI molecule can be used to transform this underlying Gaussian distribution into the observed distribution of functional sensitivity values. In the present paper, the model is extended by accounting explicitly for the kinetics of the interaction between the co-receptor and the MHCI molecule. We show that T-cells can modulate the level of degeneracy by varying the density of co-receptors on the cell surface. This could allow for an analog of avidity maturation during incipient T-cell responses.
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