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Gaglione SA, Rosales TJ, Schmidt-Hong L, Baker BM, Birnbaum ME. SARS-CoV-2 spike does not interact with the T cell receptor or directly activate T cells. Proc Natl Acad Sci U S A 2024; 121:e2406615121. [PMID: 39042676 PMCID: PMC11295079 DOI: 10.1073/pnas.2406615121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 06/25/2024] [Indexed: 07/25/2024] Open
Abstract
Suggested edit: SARS-CoV-2infection can induce multisystem inflammatory syndrome in children, which resembles superantigen-induced toxic shock syndrome. Recent work has suggested that the SARS-CoV-2 spike (S) protein could act as a superantigen by binding T cell receptors (TCRs) and inducing broad antigen-independent T cell responses. Structure-based computational modeling identified potential TCR-binding sites near the S receptor-binding domain, in addition to a site with homology to known neurotoxins. We experimentally examined the mechanism underpinning this theory-the direct interaction between the TCR and S protein. Surface plasmon resonance of recombinantly expressed S protein and TCR revealed no detectable binding. Orthogonally, we pseudotyped lentiviruses with SARS-CoV-2 S in both wild-type and prefusion-stabilized forms, demonstrated their functionality in a cell line assay, and observed no transduction, activation, or stimulation of proliferation of CD8+ T cells. We conclude that it is unlikely that the SARS-CoV-2 spike protein engages nonspecifically with TCRs or has superantigenic character.
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Affiliation(s)
- Stephanie A. Gaglione
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Tatiana J. Rosales
- Department of Chemistry and Biochemistry, University of Notre Dame, South Bend, IN46556
- Harper Cancer Research Institute, University of Notre Dame, South Bend, IN46556
| | - Laura Schmidt-Hong
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA02139
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Brian M. Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, South Bend, IN46556
- Harper Cancer Research Institute, University of Notre Dame, South Bend, IN46556
| | - Michael E. Birnbaum
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA02139
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard, Cambridge, MA02139
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2
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Hiscox MJ, Wasmuth A, Williams CL, Foot JN, Wiedermann GE, Fadda V, Boiani S, Cornforth TV, Wikiert KA, Bruton S, Cartwright N, Anderson VE, Barnes CS, Vieira JV, Birch-Machin I, Gerry AB, Miller K, Pumphrey NJ. Selection, engineering, and in vivo testing of a human leukocyte antigen-independent T-cell receptor recognizing human mesothelin. PLoS One 2024; 19:e0301175. [PMID: 38574067 PMCID: PMC10994368 DOI: 10.1371/journal.pone.0301175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 03/12/2024] [Indexed: 04/06/2024] Open
Abstract
BACKGROUND Canonical α/β T-cell receptors (TCRs) bind to human leukocyte antigen (HLA) displaying antigenic peptides to elicit T cell-mediated cytotoxicity. TCR-engineered T-cell immunotherapies targeting cancer-specific peptide-HLA complexes (pHLA) are generating exciting clinical responses, but owing to HLA restriction they are only able to target a subset of antigen-positive patients. More recently, evidence has been published indicating that naturally occurring α/β TCRs can target cell surface proteins other than pHLA, which would address the challenges of HLA restriction. In this proof-of-concept study, we sought to identify and engineer so-called HLA-independent TCRs (HiTs) against the tumor-associated antigen mesothelin. METHODS Using phage display, we identified a HiT that bound well to mesothelin, which when expressed in primary T cells, caused activation and cytotoxicity. We subsequently engineered this HiT to modulate the T-cell response to varying levels of mesothelin on the cell surface. RESULTS The isolated HiT shows cytotoxic activity and demonstrates killing of both mesothelin-expressing cell lines and patient-derived xenograft models. Additionally, we demonstrated that HiT-transduced T cells do not require CD4 or CD8 co-receptors and, unlike a TCR fusion construct, are not inhibited by soluble mesothelin. Finally, we showed that HiT-transduced T cells are highly efficacious in vivo, completely eradicating xenografted human solid tumors. CONCLUSION HiTs can be isolated from fully human TCR-displaying phage libraries against cell surface-expressed antigens. HiTs are able to fully activate primary T cells both in vivo and in vitro. HiTs may enable the efficacy seen with pHLA-targeting TCRs in solid tumors to be translated to cell surface antigens.
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Affiliation(s)
| | | | | | - Jaelle N. Foot
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
| | | | - Valeria Fadda
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
| | - Sara Boiani
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
| | | | | | - Shaun Bruton
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
| | - Neil Cartwright
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
| | | | | | - Joao V. Vieira
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
| | | | - Andrew B. Gerry
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
| | - Karen Miller
- Research, Adaptimmune, Abingdon, Oxfordshire, United Kingdom
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3
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Sadasivam M, Jie C, Hamad ARA. Renal tubular epithelial cells are constitutive non-cognate stimulators of resident T cells. Cell Rep 2023; 42:113210. [PMID: 37796661 PMCID: PMC11259314 DOI: 10.1016/j.celrep.2023.113210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/06/2023] [Accepted: 09/18/2023] [Indexed: 10/07/2023] Open
Abstract
Understanding the roles of different cell types in regulating T cell homeostasis in various tissues is critical for understanding adaptive immunity. Here, we show that RTECs (renal tubular epithelial cells) are intrinsically programmed to polyclonally stimulate proliferation of kidney αβ T cells by a cell-cell contact mechanism that is major histocompatibility complex (MHC) independent and regulated by CD155, αVβ3-integrin, and vitronectin. Peripheral CD4 and CD8 are resistant to RTEC-mediated stimulation, while the minor subset of double-negative (DN) T cells are responsive. This functional property of RTEC is discovered by using a coculture system that recapitulates spontaneous in vivo polyclonal proliferation of kidney T cells, which are mainly comprised of central memory T (TCM) and effector memory T (TEM) cells. This robust cell-intrinsic stimulatory role of RTECs could be underlying the steady-state spontaneous proliferation of kidney T cells. The results have conceptual implications for understanding roles of different cell types in regulating systemic and organ-specific T cell homeostasis.
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Affiliation(s)
- Mohanraj Sadasivam
- Department of Pathology, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross 664G, Baltimore, MD 21205, USA
| | - Chunfa Jie
- Department of Biochemistry and Nutrition, Des Moines University, 3200 Grand Avenue, Ryan Hall 230, Des Moines, IA 50266, USA
| | - Abdel Rahim A Hamad
- Department of Pathology, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross 664G, Baltimore, MD 21205, USA; Department of Medicine, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross 664G, Baltimore, MD 21205, USA.
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4
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Boughter CT, Meier-Schellersheim M. Conserved biophysical compatibility among the highly variable germline-encoded regions shapes TCR-MHC interactions. eLife 2023; 12:e90681. [PMID: 37861280 PMCID: PMC10631762 DOI: 10.7554/elife.90681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 10/19/2023] [Indexed: 10/21/2023] Open
Abstract
T cells are critically important components of the adaptive immune system primarily responsible for identifying and responding to pathogenic challenges. This recognition of pathogens is driven by the interaction between membrane-bound T cell receptors (TCRs) and antigenic peptides presented on major histocompatibility complex (MHC) molecules. The formation of the TCR-peptide-MHC complex (TCR-pMHC) involves interactions among germline-encoded and hypervariable amino acids. Germline-encoded and hypervariable regions can form contacts critical for complex formation, but only interactions between germline-encoded contacts are likely to be shared across many of all the possible productive TCR-pMHC complexes. Despite this, experimental investigation of these interactions have focused on only a small fraction of the possible interaction space. To address this, we analyzed every possible germline-encoded TCR-MHC contact in humans, thereby generating the first comprehensive characterization of these largely antigen-independent interactions. Our computational analysis suggests that germline-encoded TCR-MHC interactions that are conserved at the sequence level are rare due to the high amino acid diversity of the TCR CDR1 and CDR2 loops, and that such conservation is unlikely to dominate the dynamic protein-protein binding interface. Instead, we propose that binding properties such as the docking orientation are defined by regions of biophysical compatibility between these loops and the MHC surface.
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Affiliation(s)
- Christopher T Boughter
- Computational Biology Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of HealthBethesdaUnited States
| | - Martin Meier-Schellersheim
- Computational Biology Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of HealthBethesdaUnited States
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5
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Logunova N, Kapina M, Kondratieva E, Apt A. The H2-A Class II molecule α/β-chain cis-mismatch severely affects cell surface expression, selection of conventional CD4 + T cells and protection against TB infection. Front Immunol 2023; 14:1183614. [PMID: 37426653 PMCID: PMC10324577 DOI: 10.3389/fimmu.2023.1183614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/31/2023] [Indexed: 07/11/2023] Open
Abstract
Introduction To dissect the role of the part of the H2 complex comprised of the MHC-II genes in the control of tuberculosis (TB) infection, we previously established a panel of recombinant congenic mouse strains bearing different segments of the H2 j haplotype on the B6 (H2 b) genetic background. Fine genetic mapping, gene sequencing and assessment of TB phenotypes resulted in identification of the H2-Ab gene as a major factor of TB control. Methods We further narrowed the MHC-II H2 j interval by spotting a new recombination event, sequencing newly established DNA configuration and establishing a mouse strain B6.I-103 in which j/b recombination occurred within the coding sequence of the H2-Ab gene. Results Unexpectedly, a novel H2-Aα b/AβjE0 haplotype provided exclusively high susceptibility to TB challenge. Immunologic analysis revealed an altered CD4+ T-cell selection and maintenance in B6.I-103 mice, as well as seriously impaired expression of the H2-Aαb/Aβj molecule on the surface of antigen presenting cells. Unlike previously reported cases of Class II malfunctioning, the defective phenotype arose not from strong structural mutations, but from regular recombination events within the MHC-II recombination hot spot region. Discussion Our findings provide evidence that Class II α/β-chain cis-allelic mismatches created by regular genetic recombination may severely affect immune system functioning. This issue is discussed in the context of the MHC evolution.
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6
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Hartel JC, Merz N, Grösch S. How sphingolipids affect T cells in the resolution of inflammation. Front Pharmacol 2022; 13:1002915. [PMID: 36176439 PMCID: PMC9513432 DOI: 10.3389/fphar.2022.1002915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 08/24/2022] [Indexed: 11/13/2022] Open
Abstract
The concept of proper resolution of inflammation rather than counteracting it, gained a lot of attention in the past few years. Re-assembly of tissue and cell homeostasis as well as establishment of adaptive immunity after inflammatory processes are the key events of resolution. Neutrophiles and macrophages are well described as promotors of resolution, but the role of T cells is poorly reviewed. It is also broadly known that sphingolipids and their imbalance influence membrane fluidity and cell signalling pathways resulting in inflammation associated diseases like inflammatory bowel disease (IBD), atherosclerosis or diabetes. In this review we highlight the role of sphingolipids in T cells in the context of resolution of inflammation to create an insight into new possible therapeutical approaches.
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Affiliation(s)
- Jennifer Christina Hartel
- Institute of Clinical Pharmacology, Goethe-University Frankfurt. Frankfurt am Main, Frankfurt, Germany
- Department of Life Sciences, Goethe-University Frankfurt, Frankfurt, Germany
| | - Nadine Merz
- Institute of Clinical Pharmacology, Goethe-University Frankfurt. Frankfurt am Main, Frankfurt, Germany
| | - Sabine Grösch
- Institute of Clinical Pharmacology, Goethe-University Frankfurt. Frankfurt am Main, Frankfurt, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Frankfurt, Germany
- *Correspondence: Sabine Grösch,
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7
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CD155 in tumor progression and targeted therapy. Cancer Lett 2022; 545:215830. [PMID: 35870689 DOI: 10.1016/j.canlet.2022.215830] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 07/12/2022] [Accepted: 07/12/2022] [Indexed: 11/23/2022]
Abstract
CD155, also known as the poliovirus receptor (PVR), has received considerable attention in recent years because of its intrinsic and extrinsic roles in tumor progression. Although barely expressed in host cells, CD155 is upregulated in tumor-infiltrating myeloid cells. High expression of CD155 in tumor cells across multiple cancer types is common and associated with poor patient outcomes. The intrinsic functions of CD155 in tumor cells promote tumor progression and metastasis, whereas its extrinsic immunoregulatory functions in the tumor microenvironment (TME) involve interaction with the upregulated inhibitory immune cell receptor and checkpoint TIGIT, suggesting that CD155 and CD155 pathways are promising tumor immunotherapy targets. Preclinical studies demonstrate that targeting CD155 and its receptor (anti-TIGIT) using a single treatment or in combination with anti-PD-1 can improve immune-mediated tumor control. However, there is still a limited understanding of CD155 and its associated targeting strategies, especially antibody and immune cell editing-related strategies of CD155 in cancer. Here, we review the role of CD155 in host and tumor cells in controlling tumor progression and discuss the potential of targeting CD155 for tumor therapy.
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8
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Van Laethem F, Bhattacharya A, Craveiro M, Lu J, Sun PD, Singer A. MHC-independent αβT cells: Lessons learned about thymic selection and MHC-restriction. Front Immunol 2022; 13:953160. [PMID: 35911724 PMCID: PMC9331304 DOI: 10.3389/fimmu.2022.953160] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/24/2022] [Indexed: 12/02/2022] Open
Abstract
Understanding the generation of an MHC-restricted T cell repertoire is the cornerstone of modern T cell immunology. The unique ability of αβT cells to only recognize peptide antigens presented by MHC molecules but not conformational antigens is referred to as MHC restriction. How MHC restriction is imposed on a very large T cell receptor (TCR) repertoire is still heavily debated. We recently proposed the selection model, which posits that newly re-arranged TCRs can structurally recognize a wide variety of antigens, ranging from peptides presented by MHC molecules to native proteins like cell surface markers. However, on a molecular level, the sequestration of the essential tyrosine kinase Lck by the coreceptors CD4 and CD8 allows only MHC-restricted TCRs to signal. In the absence of Lck sequestration, MHC-independent TCRs can signal and instruct the generation of mature αβT cells that can recognize native protein ligands. The selection model thus explains how only MHC-restricted TCRs can signal and survive thymic selection. In this review, we will discuss the genetic evidence that led to our selection model. We will summarize the selection mechanism and structural properties of MHC-independent TCRs and further discuss the various non-MHC ligands we have identified.
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Affiliation(s)
- François Van Laethem
- Lymphocyte Development Section, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
- Department of Biological Hematology, Centre Hospitalier Universitaire (CHU) Montpellier, Montpellier, France
- *Correspondence: François Van Laethem, ,
| | - Abhisek Bhattacharya
- Lymphocyte Development Section, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
| | - Marco Craveiro
- Lymphocyte Development Section, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
| | - Jinghua Lu
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, United States
| | - Peter D. Sun
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, United States
| | - Alfred Singer
- Lymphocyte Development Section, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
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9
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Sim MJW, Stotz Z, Lu J, Brennan P, Long EO, Sun PD. T cells discriminate between groups C1 and C2 HLA-C. eLife 2022; 11:75670. [PMID: 35587797 PMCID: PMC9177145 DOI: 10.7554/elife.75670] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 05/15/2022] [Indexed: 01/09/2023] Open
Abstract
Dimorphic amino acids at positions 77 and 80 delineate HLA-C allotypes into two groups, C1 and C2, which associate with disease through interactions with C1 and C2-specific natural killer cell receptors. How the C1/C2 dimorphism affects T cell recognition is unknown. Using HLA-C allotypes that differ only by the C1/C2-defining residues, we found that KRAS-G12D neoantigen-specific T cell receptors (TCRs) discriminated between C1 and C2 presenting the same KRAS-G12D peptides. Structural and functional experiments, and immunopeptidomics analysis revealed that Ser77 in C1 and Asn77 in C2 influence amino acid preference near the peptide C-terminus (pΩ), including the pΩ-1 position, in which C1 favors small and C2 prefers large residues. This resulted in weaker TCR affinity for KRAS-G12D-bound C2-HLA-C despite conserved TCR contacts. Thus, the C1/C2 dimorphism on its own impacts peptide presentation and HLA-C-restricted T cell responses, with implications in disease, including adoptive T cell therapy targeting KRAS-G12D-induced cancers.
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Affiliation(s)
- Malcolm J W Sim
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of HealthRockvilleUnited States
| | - Zachary Stotz
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of HealthRockvilleUnited States
| | - Jinghua Lu
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of HealthRockvilleUnited States
| | - Paul Brennan
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of HealthRockvilleUnited States
| | - Eric O Long
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of HealthRockvilleUnited States
| | - Peter D Sun
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of HealthRockvilleUnited States
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10
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T cell receptor (TCR) signaling in health and disease. Signal Transduct Target Ther 2021; 6:412. [PMID: 34897277 PMCID: PMC8666445 DOI: 10.1038/s41392-021-00823-w] [Citation(s) in RCA: 133] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 11/02/2021] [Accepted: 11/02/2021] [Indexed: 12/18/2022] Open
Abstract
Interaction of the T cell receptor (TCR) with an MHC-antigenic peptide complex results in changes at the molecular and cellular levels in T cells. The outside environmental cues are translated into various signal transduction pathways within the cell, which mediate the activation of various genes with the help of specific transcription factors. These signaling networks propagate with the help of various effector enzymes, such as kinases, phosphatases, and phospholipases. Integration of these disparate signal transduction pathways is done with the help of adaptor proteins that are non-enzymatic in function and that serve as a scaffold for various protein-protein interactions. This process aids in connecting the proximal to distal signaling pathways, thereby contributing to the full activation of T cells. This review provides a comprehensive snapshot of the various molecules involved in regulating T cell receptor signaling, covering both enzymes and adaptors, and will discuss their role in human disease.
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11
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Zareie P, Szeto C, Farenc C, Gunasinghe SD, Kolawole EM, Nguyen A, Blyth C, Sng XYX, Li J, Jones CM, Fulcher AJ, Jacobs JR, Wei Q, Wojciech L, Petersen J, Gascoigne NRJ, Evavold BD, Gaus K, Gras S, Rossjohn J, La Gruta NL. Canonical T cell receptor docking on peptide-MHC is essential for T cell signaling. Science 2021; 372:372/6546/eabe9124. [PMID: 34083463 DOI: 10.1126/science.abe9124] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 04/23/2021] [Indexed: 12/23/2022]
Abstract
T cell receptor (TCR) recognition of peptide-major histocompatibility complexes (pMHCs) is characterized by a highly conserved docking polarity. Whether this polarity is driven by recognition or signaling constraints remains unclear. Using "reversed-docking" TCRβ-variable (TRBV) 17+ TCRs from the naïve mouse CD8+ T cell repertoire that recognizes the H-2Db-NP366 epitope, we demonstrate that their inability to support T cell activation and in vivo recruitment is a direct consequence of reversed docking polarity and not TCR-pMHCI binding or clustering characteristics. Canonical TCR-pMHCI docking optimally localizes CD8/Lck to the CD3 complex, which is prevented by reversed TCR-pMHCI polarity. The requirement for canonical docking was circumvented by dissociating Lck from CD8. Thus, the consensus TCR-pMHC docking topology is mandated by T cell signaling constraints.
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Affiliation(s)
- Pirooz Zareie
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Christopher Szeto
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Carine Farenc
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Sachith D Gunasinghe
- European Molecular Biology Laboratory (EMBL) Australia Node in Single Molecule Science and the ARC Centre of Excellence in Advanced Molecular Imaging, School of Medical Sciences, University of New South Wales, New South Wales, Australia
| | - Elizabeth M Kolawole
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Angela Nguyen
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Chantelle Blyth
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Xavier Y X Sng
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Jasmine Li
- Infection and Immunity Program and Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Claerwen M Jones
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Alex J Fulcher
- Monash Micro Imaging, Monash University, Clayton, Victoria, Australia
| | - Jesica R Jacobs
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Qianru Wei
- Immunology Translational Research Programme and Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545
| | - Lukasz Wojciech
- Immunology Translational Research Programme and Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545
| | - Jan Petersen
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia
| | - Nicholas R J Gascoigne
- Immunology Translational Research Programme and Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545
| | - Brian D Evavold
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Katharina Gaus
- European Molecular Biology Laboratory (EMBL) Australia Node in Single Molecule Science and the ARC Centre of Excellence in Advanced Molecular Imaging, School of Medical Sciences, University of New South Wales, New South Wales, Australia
| | - Stephanie Gras
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia. .,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia. .,Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia.,Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Nicole L La Gruta
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
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12
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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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13
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Mørch AM, Bálint Š, Santos AM, Davis SJ, Dustin ML. Coreceptors and TCR Signaling - the Strong and the Weak of It. Front Cell Dev Biol 2020; 8:597627. [PMID: 33178706 PMCID: PMC7596257 DOI: 10.3389/fcell.2020.597627] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 09/28/2020] [Indexed: 12/02/2022] Open
Abstract
The T-cell coreceptors CD4 and CD8 have well-characterized and essential roles in thymic development, but how they contribute to immune responses in the periphery is unclear. Coreceptors strengthen T-cell responses by many orders of magnitude - beyond a million-fold according to some estimates - but the mechanisms underlying these effects are still debated. T-cell receptor (TCR) triggering is initiated by the binding of the TCR to peptide-loaded major histocompatibility complex (pMHC) molecules on the surfaces of other cells. CD4 and CD8 are the only T-cell proteins that bind to the same pMHC ligand as the TCR, and can directly associate with the TCR-phosphorylating kinase Lck. At least three mechanisms have been proposed to explain how coreceptors so profoundly amplify TCR signaling: (1) the Lck recruitment model and (2) the pseudodimer model, both invoked to explain receptor triggering per se, and (3) two-step coreceptor recruitment to partially triggered TCRs leading to signal amplification. More recently it has been suggested that, in addition to initiating or augmenting TCR signaling, coreceptors effect antigen discrimination. But how can any of this be reconciled with TCR signaling occurring in the absence of CD4 or CD8, and with their interactions with pMHC being among the weakest specific protein-protein interactions ever described? Here, we review each theory of coreceptor function in light of the latest structural, biochemical, and functional data. We conclude that the oldest ideas are probably still the best, i.e., that their weak binding to MHC proteins and efficient association with Lck allow coreceptors to amplify weak incipient triggering of the TCR, without comprising TCR specificity.
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Affiliation(s)
- Alexander M. Mørch
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, United Kingdom
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Štefan Bálint
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, United Kingdom
| | - Ana Mafalda Santos
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Simon J. Davis
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Michael L. Dustin
- The Kennedy Institute of Rheumatology, University of Oxford, Oxford, United Kingdom
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14
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Van Laethem F, Saba I, Lu J, Bhattacharya A, Tai X, Guinter TI, Engelhardt B, Alag A, Rojano M, Ashe JM, Hanada KI, Yang JC, Sun PD, Singer A. Novel MHC-Independent αβTCRs Specific for CD48, CD102, and CD155 Self-Proteins and Their Selection in the Thymus. Front Immunol 2020; 11:1216. [PMID: 32612609 PMCID: PMC7308553 DOI: 10.3389/fimmu.2020.01216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/15/2020] [Indexed: 11/13/2022] Open
Abstract
MHC-independent αβTCRs (TCRs) recognize conformational epitopes on native self-proteins and arise in mice lacking both MHC and CD4/CD8 coreceptor proteins. Although naturally generated in the thymus, these TCRs resemble re-engineered therapeutic chimeric antigen receptor (CAR) T cells in their specificity for MHC-independent ligands. Here we identify naturally arising MHC-independent TCRs reactive to three native self-proteins (CD48, CD102, and CD155) involved in cell adhesion. We report that naturally arising MHC-independent TCRs require high affinity TCR-ligand engagements in the thymus to signal positive selection and that high affinity positive selection generates a peripheral TCR repertoire with limited diversity and increased self-reactivity. We conclude that the affinity of TCR-ligand engagements required to signal positive selection in the thymus inversely determines the diversity and self-tolerance of the mature TCR repertoire that is selected.
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Affiliation(s)
- François Van Laethem
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Ingrid Saba
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Jinghua Lu
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, MD, United States
| | - Abhisek Bhattacharya
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Xuguang Tai
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Terry I Guinter
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Britta Engelhardt
- Theodor Kocher Institute, Faculty of Bern, Universität Bern, Bern, Switzerland
| | - Amala Alag
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Mirelle Rojano
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Jennifer M Ashe
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Ken-Ichi Hanada
- Surgery Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - James C Yang
- Surgery Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
| | - Peter D Sun
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, MD, United States
| | - Alfred Singer
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Rockville, MD, United States
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15
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Lu J, Van Laethem F, Saba I, Chu J, Tikhonova AN, Bhattacharya A, Singer A, Sun PD. Structure of MHC-Independent TCRs and Their Recognition of Native Antigen CD155. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 204:3351-3359. [PMID: 32321756 PMCID: PMC7390066 DOI: 10.4049/jimmunol.1901084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 04/02/2020] [Indexed: 01/07/2023]
Abstract
During normal T cell development in the thymus, αβ TCRs signal immature thymocytes to differentiate into mature T cells by binding to peptide-MHC ligands together with CD4/CD8 coreceptors. Conversely, in MHC and CD4/CD8 coreceptor-deficient mice, the thymus generates mature T cells expressing MHC-independent TCRs that recognize native conformational epitopes rather than linear antigenic-peptides presented by MHC. To date, no structural information of MHC-independent TCRs is available, and their structural recognition of non-MHC ligand remains unknown. To our knowledge in this study, we determined the first structures of two murine MHC-independent TCRs (A11 and B12A) that bind with high nanomolar affinities to mouse adhesion receptor CD155. Solution binding demonstrated the Vαβ-domain is responsible for MHC-independent B12A recognition of its ligand. Analysis of A11 and B12A sequences against various MHC-restricted and -independent TCR sequence repertoires showed that individual V-genes of A11 and B12A did not exhibit preference against MHC-restriction. Likewise, CDR3 alone did not discriminate against MHC binding, suggesting VDJ recombination together with Vα/Vβ pairing determine their MHC-independent specificity for CD155. The structures of A11 and B12A TCR are nearly identical to those of MHC-restricted TCR, including the conformations of CDR1 and 2. Mutational analysis, together with negative-staining electron microscopy images, showed that the CDR regions of A11 and B12A recognized epitopes on D1 domain of CD155, a region also involved in CD155 binding to poliovirus and Tactile in human. Taken together, MHC-independent TCRs adopt canonical TCR structures to recognize native Ags, highlighting the importance of thymic selection in determining TCR ligand specificity.
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Affiliation(s)
- Jinghua Lu
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland 20852
| | - François Van Laethem
- Experimental Immunology Branch, National Cancer Institute, Bethesda, Maryland 20892
| | - Ingrid Saba
- Experimental Immunology Branch, National Cancer Institute, Bethesda, Maryland 20892
| | - Jonathan Chu
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland 20852
| | | | - Abhisek Bhattacharya
- Experimental Immunology Branch, National Cancer Institute, Bethesda, Maryland 20892
| | - Alfred Singer
- Experimental Immunology Branch, National Cancer Institute, Bethesda, Maryland 20892
| | - Peter D. Sun
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, Maryland 20852
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16
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High-affinity oligoclonal TCRs define effective adoptive T cell therapy targeting mutant KRAS-G12D. Proc Natl Acad Sci U S A 2020; 117:12826-12835. [PMID: 32461371 DOI: 10.1073/pnas.1921964117] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Complete cancer regression occurs in a subset of patients following adoptive T cell therapy (ACT) of ex vivo expanded tumor-infiltrating lymphocytes (TILs). However, the low success rate presents a great challenge to broader clinical application. To provide insight into TIL-based immunotherapy, we studied a successful case of ACT where regression was observed against tumors carrying the hotspot mutation G12D in the KRAS oncogene. Four T cell receptors (TCRs) made up the TIL infusion and recognized two KRAS-G12D neoantigens, a nonamer and a decamer, all restricted by human leukocyte antigen (HLA) C*08:02. Three of them (TCR9a, 9b, and 9c) were nonamer-specific, while one was decamer-specific (TCR10). We show that only mutant G12D but not the wild-type peptides stabilized HLA-C*08:02 due to the formation of a critical anchor salt bridge to HLA-C. Therapeutic TCRs exhibited high affinities, ranging from nanomolar to low micromolar. Intriguingly, TCR binding affinities to HLA-C inversely correlated with their persistence in vivo, suggesting the importance of antigenic affinity in the function of therapeutic T cells. Crystal structures of TCR-HLA-C complexes revealed that TCR9a to 9c recognized G12D nonamer with multiple conserved contacts through shared CDR2β and CDR3α. This allowed CDR3β variation to confer different affinities via a variable HLA-C contact, generating an oligoclonal response. TCR10 recognized an induced and distinct G12D decamer conformation. Thus, this successful case of ACT included oligoclonal TCRs of high affinity recognizing distinct conformations of neoantigens. Our study revealed the potential of a structural approach to inform clinical efforts in targeting KRAS-G12D tumors by immunotherapy and has general implications for T cell-based immunotherapies.
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17
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Collin R, Lombard-Vadnais F, Hillhouse EE, Lebel MÈ, Chabot-Roy G, Melichar HJ, Lesage S. MHC-Independent Thymic Selection of CD4 and CD8 Coreceptor Negative αβ T Cells. THE JOURNAL OF IMMUNOLOGY 2020; 205:133-142. [PMID: 32434937 DOI: 10.4049/jimmunol.2000156] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/23/2020] [Indexed: 12/12/2022]
Abstract
It is becoming increasingly clear that unconventional T cell subsets, such as NKT, γδ T, mucosal-associated invariant T, and CD8αα T cells, each play distinct roles in the immune response. Subsets of these cell types can lack both CD4 and CD8 coreceptor expression. Beyond these known subsets, we identify CD4-CD8-TCRαβ+, double-negative (DN) T cells, in mouse secondary lymphoid organs. DN T cells are a unique unconventional thymic-derived T cell subset. In contrast to CD5high DN thymocytes that preferentially yield TCRαβ+ CD8αα intestinal lymphocytes, we find that mature CD5low DN thymocytes are precursors to peripheral DN T cells. Using reporter mouse strains, we show that DN T cells transit through the immature CD4+CD8+ (double-positive) thymocyte stage. Moreover, we provide evidence that DN T cells can differentiate in MHC-deficient mice. Our study demonstrates that MHC-independent thymic selection can yield DN T cells that are distinct from NKT, γδ T, mucosal-associated invariant T, and CD8αα T cells.
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Affiliation(s)
- Roxanne Collin
- Immunology-Oncology Section, Maisonneuve-Rosemont Hospital Research Center, Montreal, Quebec H1T 2M4, Canada.,Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
| | - Félix Lombard-Vadnais
- Immunology-Oncology Section, Maisonneuve-Rosemont Hospital Research Center, Montreal, Quebec H1T 2M4, Canada.,Department of Microbiology and Immunology, McGill University, Montreal, Quebec H3A 0G4, Canada; and
| | - Erin E Hillhouse
- Immunology-Oncology Section, Maisonneuve-Rosemont Hospital Research Center, Montreal, Quebec H1T 2M4, Canada
| | - Marie-Ève Lebel
- Immunology-Oncology Section, Maisonneuve-Rosemont Hospital Research Center, Montreal, Quebec H1T 2M4, Canada
| | - Geneviève Chabot-Roy
- Immunology-Oncology Section, Maisonneuve-Rosemont Hospital Research Center, Montreal, Quebec H1T 2M4, Canada
| | - Heather J Melichar
- Immunology-Oncology Section, Maisonneuve-Rosemont Hospital Research Center, Montreal, Quebec H1T 2M4, Canada.,Département de Médecine, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Sylvie Lesage
- Immunology-Oncology Section, Maisonneuve-Rosemont Hospital Research Center, Montreal, Quebec H1T 2M4, Canada; .,Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
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18
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Affiliation(s)
- Pirooz Zareie
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Carine Farenc
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Nicole L. La Gruta
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Australia
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19
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20
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Abstract
The repertoire of αβ T cell antigen receptors (TCRs) on mature T cells is selected in the thymus where it is rendered both self-tolerant and restricted to the recognition of major histocompatibility complex molecules presenting peptide antigens (pMHC). It remains unclear whether germline TCR sequences exhibit an inherent bias to interact with pMHC prior to selection. Here, we isolated TCR libraries from unselected thymocytes and upon reexpression of these random TCR repertoires in recipient T cell hybridomas, interrogated their reactivities to antigen-presenting cell lines. While these random TCR combinations could potentially have reacted with any surface molecule on the cell lines, the hybridomas were stimulated most frequently by pMHC ligands. The nature and CDR3 loop composition of the TCRβ chain played a dominant role in determining pMHC-reactivity. Replacing the germline regions of mouse TCRβ chains with those of other jawed vertebrates preserved reactivity to mouse pMHC. Finally, introducing the CD4 coreceptor into the hybridomas increased the proportion of cells that could respond to pMHC ligands. Thus, αβ TCRs display an intrinsic and evolutionary conserved bias for pMHC molecules in the absence of any selective pressure, which is further strengthened in the presence of coreceptors.
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21
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Molecular constraints on CDR3 for thymic selection of MHC-restricted TCRs from a random pre-selection repertoire. Nat Commun 2019; 10:1019. [PMID: 30833553 PMCID: PMC6399321 DOI: 10.1038/s41467-019-08906-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/07/2019] [Indexed: 12/19/2022] Open
Abstract
The αβ T cell receptor (TCR) repertoire on mature T cells is selected in the thymus, but the basis for thymic selection of MHC-restricted TCRs from a randomly generated pre-selection repertoire is not known. Here we perform comparative repertoire sequence analyses of pre-selection and post-selection TCR from multiple MHC-sufficient and MHC-deficient mouse strains, and find that MHC-restricted and MHC-independent TCRs are primarily distinguished by features in their non-germline CDR3 regions, with many pre-selection CDR3 sequences not compatible with MHC-binding. Thymic selection of MHC-independent TCR is largely unconstrained, but the selection of MHC-specific TCR is restricted by both CDR3 length and specific amino acid usage. MHC-restriction disfavors TCR with CDR3 longer than 13 amino acids, limits positively charged and hydrophobic amino acids in CDR3β, and clonally deletes TCRs with cysteines in their CDR3 peptide-binding regions. Together, these MHC-imposed structural constraints form the basis to shape VDJ recombination sequences into MHC-restricted repertoires. For T cells, functional antigen receptors are selected in the thymus from a pre-selection repertoire by interaction with self MHCs. Here the authors show that specific, non-germline coded features located in the complementarity determining region 3 of the pre-selection antigen receptors are essential for the selection of MHC-restricted repertoire.
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22
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Li XY, Das I, Lepletier A, Addala V, Bald T, Stannard K, Barkauskas D, Liu J, Aguilera AR, Takeda K, Braun M, Nakamura K, Jacquelin S, Lane SW, Teng MW, Dougall WC, Smyth MJ. CD155 loss enhances tumor suppression via combined host and tumor-intrinsic mechanisms. J Clin Invest 2018; 128:2613-2625. [PMID: 29757192 DOI: 10.1172/jci98769] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 03/16/2018] [Indexed: 12/20/2022] Open
Abstract
Critical immune-suppressive pathways beyond programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) require greater attention. Nectins and nectin-like molecules might be promising targets for immunotherapy, since they play critical roles in cell proliferation and migration and exert immunomodulatory functions in pathophysiological conditions. Here, we show CD155 expression in both malignant cells and tumor-infiltrating myeloid cells in humans and mice. Cd155-/- mice displayed reduced tumor growth and metastasis via DNAM-1 upregulation and enhanced effector function of CD8+ T and NK cells, respectively. CD155-deleted tumor cells also displayed slower tumor growth and reduced metastases, demonstrating the importance of a tumor-intrinsic role of CD155. CD155 absence on host and tumor cells exerted an even greater inhibition of tumor growth and metastasis. Blockade of PD-1 or both PD-1 and CTLA4 was more effective in settings in which CD155 was limiting, suggesting the clinical potential of cotargeting PD-L1 and CD155 function.
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Affiliation(s)
- Xian-Yang Li
- Immunology in Cancer and Infection Laboratory and
| | - Indrajit Das
- Immunology in Cancer and Infection Laboratory and
| | | | - Venkateswar Addala
- Medical Genomics, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Tobias Bald
- Immunology in Cancer and Infection Laboratory and
| | | | | | - Jing Liu
- Immunology in Cancer and Infection Laboratory and
| | | | - Kazuyoshi Takeda
- Division of Cell Biology, Biomedical Research Center and Department of Biofunctional Microbiota, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | | | | | - Sebastien Jacquelin
- Gordon and Jessie Gilmour Leukaemia Research Laboratory, Immunology Department, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Steven W Lane
- Gordon and Jessie Gilmour Leukaemia Research Laboratory, Immunology Department, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.,The Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.,School of Medicine, The University of Queensland, Herston, Queensland, Australia
| | - Michele Wl Teng
- School of Medicine, The University of Queensland, Herston, Queensland, Australia.,Cancer Immunoregulation and Immunotherapy and
| | - William C Dougall
- Immunology in Cancer and Infection Laboratory and.,Immuno-oncology Discovery, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Mark J Smyth
- Immunology in Cancer and Infection Laboratory and.,School of Medicine, The University of Queensland, Herston, Queensland, Australia
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23
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24
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Kuo P, Tuong ZK, Teoh SM, Frazer IH, Mattarollo SR, Leggatt GR. HPV16E7-Induced Hyperplasia Promotes CXCL9/10 Expression and Induces CXCR3 + T-Cell Migration to Skin. J Invest Dermatol 2017; 138:1348-1359. [PMID: 29277541 DOI: 10.1016/j.jid.2017.12.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/28/2017] [Accepted: 12/12/2017] [Indexed: 11/25/2022]
Abstract
Chemokines regulate tissue immunity by recruiting specific subsets of immune cells. Mice expressing the E7 protein of human papilloma virus 16 as a transgene from a keratin 14 promoter (K14.E7) show increased epidermal and dermal lymphocytic infiltrates, epidermal hyperplasia, and suppressed local immunity. Here, we show that CXCL9 and CXCL10 are overexpressed in non-hematopoietic cells in skin of K14.E7 mice when compared with non-transgenic animals, and recruit CXCR3+ lymphocytes to the hyperplastic skin. Overexpression of CXCL9 and CXCL10 is not observed in E7 transgenic mice with mutated Rb gene whose protein product cannot interact with E7 (K14.E7xRbΔL/ΔL) and in consequence lack hyperplastic epithelium. CXCR3+ T cells are preferentially recruited by CXCL9 and CXCL10 in supernatants of K14.E7 but not K14.E7xRbΔL/ΔL skin cultures in vitro. CXCR3 signalling promotes infiltration of a subset of effector T lymphocytes that enables donor lymphocyte deficient, E7-expressing skin graft rejection. Taken together, this suggests that recruitment of CXCR3+ T cells can be an important factor in the rejection of precancerous skin epithelium providing they can overcome local immunosuppressive mechanisms driven by skin-resident lymphocytes.
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Affiliation(s)
- Paula Kuo
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Zewen K Tuong
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Siok Min Teoh
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Ian H Frazer
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, Queensland, Australia.
| | - Stephen R Mattarollo
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Graham R Leggatt
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, Queensland, Australia
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25
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Abstract
Thymocyte selection involves the positive and negative selection of the repertoire of T cell receptors (TCRs) such that the organism does not suffer autoimmunity, yet has the benefit of the ability to recognize any invading pathogen. The signal transduced through the TCR is translated into a number of different signaling cascades that result in transcription factor activity in the nucleus and changes to the cytoskeleton and motility. Negative selection involves inducing apoptosis in thymocytes that express strongly self-reactive TCRs, whereas positive selection must induce survival and differentiation programs in cells that are more weakly self-reactive. The TCR recognition event is analog by nature, but the outcome of signaling is not. A large number of molecules regulate the strength of the TCR-derived signal at various points in the cascades. This review discusses the various factors that can regulate the strength of the TCR signal during thymocyte development.
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Affiliation(s)
- Nicholas R J Gascoigne
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, and Immunology Program, National University of Singapore, Singapore 11759;
| | - Vasily Rybakin
- Laboratory of Immunobiology, REGA Institute, Department of Microbiology and Immunology, KU Leuven, Leuven 3000, Belgium
| | - Oreste Acuto
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Joanna Brzostek
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, and Immunology Program, National University of Singapore, Singapore 11759;
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26
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Mallis RJ, Arthanari H, Lang MJ, Reinherz EL, Wagner G. NMR-directed design of pre-TCRβ and pMHC molecules implies a distinct geometry for pre-TCR relative to αβTCR recognition of pMHC. J Biol Chem 2017; 293:754-766. [PMID: 29101227 DOI: 10.1074/jbc.m117.813493] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 10/20/2017] [Indexed: 11/06/2022] Open
Abstract
The pre-T cell receptor (pre-TCR) guides early thymocytes through maturation processes within the thymus via interaction with self-ligands displayed on thymic epithelial cells. The pre-TCR is a disulfide-linked heterodimer composed of an invariant pre-TCR α (pTα) subunit and a variable β subunit, the latter of which is incorporated into the mature TCR in subsequent developmental progression. This interaction of pre-TCR with peptide-major histocompatibility complex (pMHC) molecules has recently been shown to drive robust pre-TCR signaling and thymocyte maturation. Although the native sequences of β are properly folded and suitable for NMR studies in isolation, a tendency to self-associate rendered binding studies with physiological ligands difficult to interpret. Consequently, to structurally define this critical interaction, we have re-engineered the extracellular regions of β, designated as β-c1, for prokaryotic production to be used in NMR spectroscopy. Given the large size of the full extracellular domain of class I MHC molecules such as H-Kb, we produced a truncated form termed Kb-t harboring properties favorable for NMR measurements. This system has enabled robust measurement of a pre-TCR-pMHC interaction directly analogous to that of TCRαβ-pMHC. Binding surface analysis identified a contact surface comparable in size to that of the TCRαβ-pMHC but potentially with a rather distinct binding orientation. A tilting of the pre-TCRβ when bound to the pMHC ligand recognition surface versus the upright orientation of TCRαβ would alter the direction of force application between pre-TCR and TCR mechanosensors, impacting signal initiation.
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Affiliation(s)
- Robert J Mallis
- From the Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
| | - Haribabu Arthanari
- From the Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115.,Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115
| | - Matthew J Lang
- Department of Chemical and Biomolecular Engineering, Vanderbilt University and Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee 37235, and
| | - Ellis L Reinherz
- Department of Medical Oncology, Laboratory of Immunobiology, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115
| | - Gerhard Wagner
- From the Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115,
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27
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Abstract
Major histocompatibility complex (MHC) restriction is a unique feature of T cell antigen recognition. Mature T cells respond to antigenic nonself peptides bound to self-MHC molecules, but a sizeable fraction of peripheral T cells can also respond to nonself peptide-MHC (pMHC) complexes in the context of transplantation. MHC specificity of the T cell receptor (TCR) repertoire is shaped during thymic development. Two hypotheses have been proposed to explain MHC specificity of T cells. It has been suggested that MHC specificity is an intrinsic feature of TCR structure, mediated by the germline-encoded regions of the TCR sequence. In support of this model, an estimated 15% to 30% of preselection TCR repertoire is estimated to be MHC-specific. Moreover, structural studies have shown some degree of conserved binding topology for TCR-peptide MHC complexes. However, there is also evidence that MHC restriction can be imposed on the TCR repertoire during thymic development, and it has been proposed that the interaction of the Lck kinase with CD4 or CD8 coreceptors is critical for generation of MHC specificity. This review will discuss recent work on assessment of the preselection of TCR repertoire, molecular evidence for the germline encoded TCR bias for MHC, and for the coreceptor sequestration model in the context of alloreactivity and transplantation.
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28
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Chen X, Poncette L, Blankenstein T. Human TCR-MHC coevolution after divergence from mice includes increased nontemplate-encoded CDR3 diversity. J Exp Med 2017; 214:3417-3433. [PMID: 28835417 PMCID: PMC5679170 DOI: 10.1084/jem.20161784] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 06/19/2017] [Accepted: 07/19/2017] [Indexed: 12/14/2022] Open
Abstract
Chen et al. demonstrate that human MHC selects a larger human TCR repertoire than mouse MHC. They show how humans optimized TCR diversity and suggest that CDR3 length adjusts for different V segment–MHC affinity. For thymic selection and responses to pathogens, T cells interact through their αβ T cell receptor (TCR) with peptide–major histocompatibility complex (MHC) molecules on antigen-presenting cells. How the diverse TCRs interact with a multitude of MHC molecules is unresolved. It is also unclear how humans generate larger TCR repertoires than mice do. We compared the TCR repertoire of CD4 T cells selected from a single mouse or human MHC class II (MHC II) in mice containing the human TCR gene loci. Human MHC II yielded greater thymic output and a more diverse TCR repertoire. The complementarity determining region 3 (CDR3) length adjusted for different inherent V-segment affinities to MHC II. Humans evolved with greater nontemplate-encoded CDR3 diversity than did mice. Our data, which demonstrate human TCR–MHC coevolution after divergence from rodents, explain the greater T cell diversity in humans and suggest a mechanism for ensuring that any V–J gene combination can be selected by a single MHC II.
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Affiliation(s)
- Xiaojing Chen
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany.,Charité Campus Buch, Institute of Immunology, Berlin, Germany
| | - Lucia Poncette
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Thomas Blankenstein
- Max-Delbrück-Center for Molecular Medicine, Berlin, Germany .,Charité Campus Buch, Institute of Immunology, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany
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29
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Madi A, Poran A, Shifrut E, Reich-Zeliger S, Greenstein E, Zaretsky I, Arnon T, Laethem FV, Singer A, Lu J, Sun PD, Cohen IR, Friedman N. T cell receptor repertoires of mice and humans are clustered in similarity networks around conserved public CDR3 sequences. eLife 2017; 6. [PMID: 28731407 PMCID: PMC5553937 DOI: 10.7554/elife.22057] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 07/14/2017] [Indexed: 01/09/2023] Open
Abstract
Diversity of T cell receptor (TCR) repertoires, generated by somatic DNA rearrangements, is central to immune system function. However, the level of sequence similarity of TCR repertoires within and between species has not been characterized. Using network analysis of high-throughput TCR sequencing data, we found that abundant CDR3-TCRβ sequences were clustered within networks generated by sequence similarity. We discovered a substantial number of public CDR3-TCRβ segments that were identical in mice and humans. These conserved public sequences were central within TCR sequence-similarity networks. Annotated TCR sequences, previously associated with self-specificities such as autoimmunity and cancer, were linked to network clusters. Mechanistically, CDR3 networks were promoted by MHC-mediated selection, and were reduced following immunization, immune checkpoint blockade or aging. Our findings provide a new view of T cell repertoire organization and physiology, and suggest that the immune system distributes its TCR sequences unevenly, attending to specific foci of reactivity. DOI:http://dx.doi.org/10.7554/eLife.22057.001
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Affiliation(s)
- Asaf Madi
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Asaf Poran
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Eric Shifrut
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | | | - Erez Greenstein
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Irena Zaretsky
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Tomer Arnon
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.,Department of Physics and Astronomy, Alfred University, Alfred, United States
| | - Francois Van Laethem
- Experimental Immunology Branch, National Cancer Institute, Bethesda, United States
| | - Alfred Singer
- Experimental Immunology Branch, National Cancer Institute, Bethesda, United States
| | - Jinghua Lu
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, United States
| | - Peter D Sun
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, United States
| | - Irun R Cohen
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Nir Friedman
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
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30
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He Y, Peng H, Sun R, Wei H, Ljunggren HG, Yokoyama WM, Tian Z. Contribution of inhibitory receptor TIGIT to NK cell education. J Autoimmun 2017; 81:1-12. [PMID: 28438433 DOI: 10.1016/j.jaut.2017.04.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/01/2017] [Accepted: 04/03/2017] [Indexed: 01/20/2023]
Abstract
Engagement of inhibitory receptors by cognate host MHC-I molecules triggers NK cell education, resulting in functional maturation and allowing NK cells to sense missing-self. However, NK cells also express inhibitory receptors for non-MHC-I ligands and their role in NK cell education is poorly understood. TIGIT is a recently identified inhibitory receptor that recognizes a non-MHC-I ligand CD155. Here, we demonstrated that TIGIT+ NK cells from wild-type mice exerted augmented responsiveness to various stimuli, including targets that lacked expression of CD155 ligand. TIGIT+ NK cells derived from CD155-deficient hosts, however, exhibited functional impairment, indicating that the engagement of TIGIT receptor by host CD155 promoted NK cell functional maturation. Furthermore, TIGIT deficiency impaired NK cell-mediated missing-self recognition and rejection of CD155- targets, such as allogenic splenocytes and certain tumor cells, in an MHC-I-independent and CD226-unrelated manner. Thus, TIGIT-CD155 pathway is also involved in the acquisition of optimal NK cell effector function, representing a novel MHC-I-independent education mechanism for NK cell tolerance and activation.
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Affiliation(s)
- Yuke He
- Institute of Immunology, Key Laboratory of Innate Immunity and Chronic Disease of Chinese Academy of Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230027, China
| | - Hui Peng
- Institute of Immunology, Key Laboratory of Innate Immunity and Chronic Disease of Chinese Academy of Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230027, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China
| | - Rui Sun
- Institute of Immunology, Key Laboratory of Innate Immunity and Chronic Disease of Chinese Academy of Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230027, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China.
| | - Haiming Wei
- Institute of Immunology, Key Laboratory of Innate Immunity and Chronic Disease of Chinese Academy of Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230027, China
| | - Hans-Gustaf Ljunggren
- Center for Infectious Medicine, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, 16451, Sweden
| | - Wayne M Yokoyama
- Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri, 63123, USA
| | - Zhigang Tian
- Institute of Immunology, Key Laboratory of Innate Immunity and Chronic Disease of Chinese Academy of Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230027, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China.
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31
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Baker BM, Evavold BD. MHC Bias by T Cell Receptors: Genetic Evidence for MHC and TCR Coevolution. Trends Immunol 2016; 38:2-4. [PMID: 27939452 DOI: 10.1016/j.it.2016.11.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 11/07/2016] [Indexed: 01/15/2023]
Abstract
Major histocompatibility complex (MHC) restriction is a fundamental tenet of T cell biology, but the underlying mechanisms have remained controversial. The extent to which T cell receptors (TCRs) are biased towards MHC proteins in particular has been widely discussed. In a recent paper, Sharon et al. report direct evidence for coevolution between TCR and MHC genes, helping to explain how MHC compatibility and bias can be encoded within TCRs.
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Affiliation(s)
- Brian M Baker
- Department of Chemistry and Biochemistry, and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN, USA
| | - Brian D Evavold
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, USA.
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32
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Attaf M, Holland SJ, Bartok I, Dyson J. αβ T cell receptor germline CDR regions moderate contact with MHC ligands and regulate peptide cross-reactivity. Sci Rep 2016; 6:35006. [PMID: 27775030 PMCID: PMC5075794 DOI: 10.1038/srep35006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 09/22/2016] [Indexed: 12/18/2022] Open
Abstract
αβ T cells respond to peptide epitopes presented by major histocompatibility complex (MHC) molecules. The role of T cell receptor (TCR) germline complementarity determining regions (CDR1 and 2) in MHC restriction is not well understood. Here, we examine T cell development, MHC restriction and antigen recognition where germline CDR loop structure has been modified by multiple glycine/alanine substitutions. Surprisingly, loss of germline structure increases TCR engagement with MHC ligands leading to excessive loss of immature thymocytes. MHC restriction is, however, strictly maintained. The peripheral T cell repertoire is affected similarly, exhibiting elevated cross-reactivity to foreign peptides. Our findings are consistent with germline TCR structure optimising T cell cross-reactivity and immunity by moderating engagement with MHC ligands. This strategy may operate alongside co-receptor imposed MHC restriction, freeing germline TCR structure to adopt this novel role in the TCR-MHC interface.
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Affiliation(s)
- Meriem Attaf
- Section of Molecular Immunology, Department of Medicine, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Stephan J Holland
- Section of Molecular Immunology, Department of Medicine, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Istvan Bartok
- Section of Molecular Immunology, Department of Medicine, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Julian Dyson
- Section of Molecular Immunology, Department of Medicine, Imperial College London, Du Cane Road, London, W12 0NN, UK
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33
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Reversed T Cell Receptor Docking on a Major Histocompatibility Class I Complex Limits Involvement in the Immune Response. Immunity 2016; 45:749-760. [PMID: 27717799 DOI: 10.1016/j.immuni.2016.09.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 07/14/2016] [Accepted: 08/06/2016] [Indexed: 01/12/2023]
Abstract
The anti-viral T cell response is drawn from the naive T cell repertoire. During influenza infection, the CD8+ T cell response to an H-2Db-restricted nucleoprotein epitope (NP366) is characterized by preferential expansion of T cells bearing TRBV13+ T cell receptors (TCRs) and avoidance of TRBV17+ T cells, despite the latter dominating the naive precursor repertoire. We found two TRBV17+ TCRs that bound H-2Db-NP366 with a 180° reversed polarity compared to the canonical TCR-pMHC-I docking. The TRBV17 β-chain dominated the interaction and, whereas the complementarity determining region-3 (CDR3) loops exclusively mediated contacts with the MHC-I, peptide specificity was attributable to germline-encoded recognition. Nevertheless, the TRBV17+ TCR exhibited moderate affinity toward H-2Db-NP366 and was capable of signal transduction. Thus, the naive CD8+ T cell pool can comprise TCRs adopting reversed pMHC-I docking modes that limit their involvement in the immune response.
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34
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Class II major histocompatibility complex mutant mice to study the germ-line bias of T-cell antigen receptors. Proc Natl Acad Sci U S A 2016; 113:E5608-17. [PMID: 27588903 DOI: 10.1073/pnas.1609717113] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The interaction of αβ T-cell antigen receptors (TCRs) with peptides bound to MHC molecules lies at the center of adaptive immunity. Whether TCRs have evolved to react with MHC or, instead, processes in the thymus involving coreceptors and other molecules select MHC-specific TCRs de novo from a random repertoire is a longstanding immunological question. Here, using nuclease-targeted mutagenesis, we address this question in vivo by generating three independent lines of knockin mice with single-amino acid mutations of conserved class II MHC amino acids that often are involved in interactions with the germ-line-encoded portions of TCRs. Although the TCR repertoire generated in these mutants is similar in size and diversity to that in WT mice, the evolutionary bias of TCRs for MHC is suggested by a shift and preferential use of some TCR subfamilies over others in mice expressing the mutant class II MHCs. Furthermore, T cells educated on these mutant MHC molecules are alloreactive to each other and to WT cells, and vice versa, suggesting strong functional differences among these repertoires. Taken together, these results highlight both the flexibility of thymic selection and the evolutionary bias of TCRs for MHC.
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35
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Rodríguez-Rodríguez N, Apostolidis SA, Fitzgerald L, Meehan BS, Corbett AJ, Martín-Villa JM, McCluskey J, Tsokos GC, Crispín JC. Pro-inflammatory self-reactive T cells are found within murine TCR-αβ(+) CD4(-) CD8(-) PD-1(+) cells. Eur J Immunol 2016; 46:1383-91. [PMID: 27060346 DOI: 10.1002/eji.201546056] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 02/23/2016] [Accepted: 03/30/2016] [Indexed: 11/07/2022]
Abstract
TCR-αβ(+) double negative (DN) T cells (CD3(+) TCR-αβ(+) CD4(-) CD8(-) NK1.1(-) CD49b(-) ) represent a minor heterogeneous population in healthy humans and mice. These cells have been ascribed pro-inflammatory and regulatory capacities and are known to expand during the course of several autoimmune diseases. Importantly, previous studies have shown that self-reactive CD8(+) T cells become DN after activation by self-antigens, suggesting that self-reactive T cells may exist within the DN T-cell population. Here, we demonstrate that programmed cell death 1 (PD-1) expression in unmanipulated mice identifies a subset of DN T cells with expression of activation-associated markers and a phenotype that strongly suggests they are derived from self-reactive CD8(+) cells. We also found that, within DN T cells, the PD-1(+) subset generates the majority of pro-inflammatory cytokines. Finally, using a TCR-activation reporter mouse (Nur77-GFP), we confirmed that in the steady-state PD-1(+) DN T cells engage endogenous antigens in healthy mice. In conclusion, we provide evidence that indicates that the PD-1(+) fraction of DN T cells represents self-reactive cells.
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Affiliation(s)
- Noé Rodríguez-Rodríguez
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Departamento de Inmunología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
- Departamento de Inmunología y Reumatología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
| | - Sokratis A Apostolidis
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Lauren Fitzgerald
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Bronwyn S Meehan
- The Department of Microbiology and Immunology, The University of Melbourne and The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Alexandra J Corbett
- The Department of Microbiology and Immunology, The University of Melbourne and The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - José Manuel Martín-Villa
- Departamento de Inmunología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - James McCluskey
- The Department of Microbiology and Immunology, The University of Melbourne and The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - George C Tsokos
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - José C Crispín
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Departamento de Inmunología y Reumatología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
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36
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Kourepini E, Paschalidis N, Simoes DCM, Aggelakopoulou M, Grogan JL, Panoutsakopoulou V. TIGIT Enhances Antigen-Specific Th2 Recall Responses and Allergic Disease. THE JOURNAL OF IMMUNOLOGY 2016; 196:3570-80. [PMID: 27016609 DOI: 10.4049/jimmunol.1501591] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 02/23/2016] [Indexed: 01/19/2023]
Abstract
T cell Ig and ITIM domain receptor (TIGIT), expressed on T, NK, and regulatory T cells, is known as an inhibitory molecule that limits autoimmunity, antiviral and antitumor immunity. In this report, we demonstrate that TIGIT enhances Th2 immunity. TIGIT expression was upregulated in activated Th2 cells from mice with experimental allergic disease and in Th2 polarization cultures. In addition, its high-affinity ligand CD155 was upregulated in mediastinal lymph node dendritic cells from allergic mice. In an in vitro setting, we observed that Tigit expression in Th2 cells and its interaction with CD155 expressed in dendritic cells were important during the development of Th2 responses. In addition, blockade of TIGIT inhibited Th2, but had no effect on either Th1 or Th17 polarization. In vivo blockade of TIGIT suppressed hallmarks of allergic airway disease, such as lung eosinophilia, goblet cell hyperplasia, Ag-specific Th2 responses, and IgE production, and reduced numbers of T follicular helper and effector Th2 cells. Thus, TIGIT is critical for Th2 immunity and can be used as a therapeutic target, especially in light of recent findings showing TIGIT locus hypomethylation in T cells from pediatric patients with allergic asthma.
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Affiliation(s)
- Evangelia Kourepini
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens 115 27, Greece; and
| | - Nikolaos Paschalidis
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens 115 27, Greece; and
| | - Davina C M Simoes
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens 115 27, Greece; and
| | - Maria Aggelakopoulou
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens 115 27, Greece; and
| | - Jane L Grogan
- Department of Cancer Immunology, Genentech, South San Francisco, CA 94080
| | - Vily Panoutsakopoulou
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens 115 27, Greece; and
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37
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How structural adaptability exists alongside HLA-A2 bias in the human αβ TCR repertoire. Proc Natl Acad Sci U S A 2016; 113:E1276-85. [PMID: 26884163 DOI: 10.1073/pnas.1522069113] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
How T-cell receptors (TCRs) can be intrinsically biased toward MHC proteins while simultaneously display the structural adaptability required to engage diverse ligands remains a controversial puzzle. We addressed this by examining αβ TCR sequences and structures for evidence of physicochemical compatibility with MHC proteins. We found that human TCRs are enriched in the capacity to engage a polymorphic, positively charged "hot-spot" region that is almost exclusive to the α1-helix of the common human class I MHC protein, HLA-A*0201 (HLA-A2). TCR binding necessitates hot-spot burial, yielding high energetic penalties that must be offset via complementary electrostatic interactions. Enrichment of negative charges in TCR binding loops, particularly the germ-line loops encoded by the TCR Vα and Vβ genes, provides this capacity and is correlated with restricted positioning of TCRs over HLA-A2. Notably, this enrichment is absent from antibody genes. The data suggest a built-in TCR compatibility with HLA-A2 that biases receptors toward, but does not compel, particular binding modes. Our findings provide an instructional example for how structurally pliant MHC biases can be encoded within TCRs.
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38
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Cohn M. Thoughts on Positive Selection in Thymus. Scand J Immunol 2016; 83:303-10. [PMID: 26834041 DOI: 10.1111/sji.12415] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 01/25/2016] [Indexed: 12/25/2022]
Abstract
Any analysis of the mechanism of signalling during positive selection in the thymus is dependent on one's model of the TCR-ligand interaction. To date, thinking about mechanism has been dominated by what might be termed the Standard (or Centric) model, which is based on analogy between the BCR and the TCR. As the present analysis is an independent rationalized view of the TCR-ligand interactions, it permits a more balanced view of positive selection. The goal here was to explore this alternative to the Standard model.
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Affiliation(s)
- M Cohn
- Conceptual Immunology Group, The Salk Institute, La Jolla, CA, USA
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39
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Structural interplay between germline interactions and adaptive recognition determines the bandwidth of TCR-peptide-MHC cross-reactivity. Nat Immunol 2016; 17:87-94. [PMID: 26523866 PMCID: PMC4684756 DOI: 10.1038/ni.3310] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 09/29/2015] [Indexed: 01/07/2023]
Abstract
The T cell antigen receptor (TCR)-peptide-major histocompatibility complex (MHC) interface is composed of conserved and diverse regions, yet the relative contribution of each in shaping recognition by T cells remains unclear. Here we isolated cross-reactive peptides with limited homology, which allowed us to compare the structural properties of nine peptides for a single TCR-MHC pair. The TCR's cross-reactivity was rooted in highly similar recognition of an apical 'hot-spot' position in the peptide with tolerance of sequence variation at ancillary positions. Furthermore, we found a striking structural convergence onto a germline-mediated interaction between the TCR CDR1α region and the MHC α2 helix in twelve TCR-peptide-MHC complexes. Our studies suggest that TCR-MHC germline-mediated constraints, together with a focus on a small peptide hot spot, might place limits on peptide antigen cross-reactivity.
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40
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T cell receptor reversed polarity recognition of a self-antigen major histocompatibility complex. Nat Immunol 2015; 16:1153-61. [DOI: 10.1038/ni.3271] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 08/10/2015] [Indexed: 12/12/2022]
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41
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Abstract
The structure and amino acid diversity of the T-cell receptor (TCR), similar in nature to that of Fab portions of antibodies, would suggest that these proteins have a nearly infinite capacity to recognize antigen. Yet all currently defined native T cells expressing an α and β chain in their TCR can only sense antigen when presented in the context of a major histocompatibility complex (MHC) molecule. This MHC molecule can be one of many that exist in vertebrates, presenting small peptide fragments, lipid molecules, or small molecule metabolites. Here we review the pattern of TCR recognition of MHC molecules throughout a broad sampling of species and T-cell lineages and also touch upon T cells that do not appear to require MHC presentation for their surveillance function. We review the diversity of MHC molecules and information on the corresponding T-cell lineages identified in divergent species. We also discuss TCRs with structural domains unlike that of conventional TCRs of mouse and human. By presenting this broad view of TCR sequence, structure, domain organization, and function, we seek to explore how this receptor has evolved across time and been selected for alternative antigen-recognition capabilities in divergent lineages.
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Affiliation(s)
- Caitlin C. Castro
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Committee on Immunology, University of Chicago, Chicago, IL, USA
| | - Adrienne M. Luoma
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Committee on Immunology, University of Chicago, Chicago, IL, USA
| | - Erin J. Adams
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Committee on Immunology, University of Chicago, Chicago, IL, USA
- Committee on Cancer Biology, University of Chicago, Chicago, IL, USA
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42
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Attaf M, Legut M, Cole DK, Sewell AK. The T cell antigen receptor: the Swiss army knife of the immune system. Clin Exp Immunol 2015; 181:1-18. [PMID: 25753381 PMCID: PMC4469151 DOI: 10.1111/cei.12622] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2015] [Indexed: 01/01/2023] Open
Abstract
The mammalian T cell receptor (TCR) orchestrates immunity by responding to many billions of different ligands that it has never encountered before and cannot adapt to at the protein sequence level. This remarkable receptor exists in two main heterodimeric isoforms: αβ TCR and γδ TCR. The αβ TCR is expressed on the majority of peripheral T cells. Most αβ T cells recognize peptides, derived from degraded proteins, presented at the cell surface in molecular cradles called major histocompatibility complex (MHC) molecules. Recent reports have described other αβ T cell subsets. These 'unconventional' T cells bear TCRs that are capable of recognizing lipid ligands presented in the context of the MHC-like CD1 protein family or bacterial metabolites bound to the MHC-related protein 1 (MR1). γδ T cells constitute a minority of the T cell pool in human blood, but can represent up to half of total T cells in tissues such as the gut and skin. The identity of the preferred ligands for γδ T cells remains obscure, but it is now known that this receptor can also functionally engage CD1-lipid, or immunoglobulin (Ig) superfamily proteins called butyrophilins in the presence of pyrophosphate intermediates of bacterial lipid biosynthesis. Interactions between TCRs and these ligands allow the host to discriminate between self and non-self and co-ordinate an attack on the latter. Here, we describe how cells of the T lymphocyte lineage and their antigen receptors are generated and discuss the various modes of antigen recognition by these extraordinarily versatile receptors.
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Affiliation(s)
- M Attaf
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - M Legut
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - D K Cole
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - A K Sewell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
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43
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Reinherz EL, Wang JH. Codification of bidentate pMHC interaction with TCR and its co-receptor. Trends Immunol 2015; 36:300-6. [PMID: 25818864 PMCID: PMC4420642 DOI: 10.1016/j.it.2015.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 02/03/2023]
Abstract
A 1983 Immunology Today rostrum hypothesized that each T cell has two recognition units: a T cell receptor (TCR) complex, which binds antigen associated with a polymorphic region of a MHC molecule (pMHC), and a CD4 or CD8 molecule that binds to a conserved region of that same MHC gene product (class II or I, respectively). Structural biology has since precisely revealed those bidentate pMHC interactions. TCRαβ ligates the membrane-distal antigen-binding MHC platform, whereas CD8 clamps a membrane-proximal MHCI α3 domain loop and CD4 docks to a hydrophobic crevice between MHCII α2 and β2 domains. Here, we review how MHC class-restricted binding impacts signaling and lineage commitment, discussing TCR force-driven conformational transitions that may optimally expose the co-receptor docking site on MHC.
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Affiliation(s)
- Ellis L Reinherz
- Laboratory of Immunobiology and Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
| | - Jia-huai Wang
- Laboratory of Immunobiology and Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
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44
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Soluble T-cell receptors produced in human cells for targeted delivery. PLoS One 2015; 10:e0119559. [PMID: 25875651 PMCID: PMC4395278 DOI: 10.1371/journal.pone.0119559] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 01/14/2015] [Indexed: 12/15/2022] Open
Abstract
Recently, technology has become available to generate soluble T-cell receptors (sTCRs) that contain the antigen recognition part. In contrast to antibodies, sTCRs recognize intracellular in addition to extracellular epitopes, potentially increasing the number of applications as reagents for target detection and immunotherapy. Moreover, recent data show that they can be used for identification of their natural peptide ligands in disease. Here we describe a new and simplified expression method for sTCRs in human cells and show that these sTCRs can be used for antigen-specific labeling and elimination of human target cells. Four different TCRs were solubilized by expression of constructs encoding the TCR alpha (α) and beta (β) chains lacking the transmembrane and intracellular domains, linked by a ribosomal skipping 2A sequence that facilitates equimolar production of the chains. Cell supernatants containing sTCRs labeled target cells directly in a peptide (p)-human leukocyte antigen (HLA)-specific manner. We demonstrated that a MART-1p/HLA-A*02:01-specific sTCR fused to a fluorescent protein, or multimerized onto magnetic nanoparticles, could be internalized. Moreover, we showed that this sTCR and two sTCRs recognizing CD20p/HLA-A*02:01 could mediate selective elimination of target cells expressing the relevant pHLA complex when tetramerized to streptavidin-conjugated toxin, demonstrating the potential for specific delivery of cargo. This simple and efficient method can be utilized to generate a wide range of minimally modified sTCRs from the naturally occurring TCR repertoire for antigen-specific detection and targeting.
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T-cell reprogramming through targeted CD4-coreceptor and T-cell receptor expression on maturing thymocytes by latent Circoviridae family member porcine circovirus type 2 cell infections in the thymus. Emerg Microbes Infect 2015; 4:e15. [PMID: 26038767 PMCID: PMC4355439 DOI: 10.1038/emi.2015.15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 10/20/2014] [Accepted: 01/31/2015] [Indexed: 02/07/2023]
Abstract
Although porcine circovirus type 2 (PCV2)-associated diseases have been evaluated for known immune evasion strategies, the pathogenicity of these viruses remained concealed for decades. Surprisingly, the same viruses that cause panzootics in livestock are widespread in young, unaffected animals. Recently, evidence has emerged that circovirus-like viruses are also linked to complex diseases in humans, including children. We detected PCV2 genome-carrying cells in fetal pig thymi. To elucidate virus pathogenicity, we developed a new pig infection model by in vivo transfection of recombinant PCV2 and the immunosuppressant cofactor cyclosporine A. Using flow cytometry, immunofluorescence and fluorescence in situ hybridization, we found evidence that PCV2 dictates positive and negative selection of maturing T cells in the thymus. We show for the first time that PCV2-infected cells reside at the corticomedullary junction of the thymus. In diseased animals, we found polyclonal deletion of single positive cells (SPs) that may result from a loss of major histocompatibility complex class-II expression at the corticomedullary junction. The percentage of PCV2 antigen-presenting cells correlated with the degree of viremia and, in turn, the severity of the defect in thymocyte maturation. Moreover, the reversed T-cell receptor/CD4-coreceptor expression dichotomy on thymocytes at the CD4+CD8interm and CD4SP cell stage is viremia-dependent, resulting in a specific hypo-responsiveness of T-helper cells. We compare our results with the only other better-studied member of Circoviridae, chicken anemia virus. Our data show that PCV2 infection leads to thymocyte selection dysregulation, adding a valuable dimension to our understanding of virus pathogenicity.
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Birkinshaw RW, Pellicci DG, Cheng TY, Keller AN, Sandoval-Romero M, Gras S, de Jong A, Uldrich AP, Moody DB, Godfrey DI, Rossjohn J. αβ T cell antigen receptor recognition of CD1a presenting self lipid ligands. Nat Immunol 2015; 16:258-66. [PMID: 25642819 DOI: 10.1038/ni.3098] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 01/06/2015] [Indexed: 12/15/2022]
Abstract
A central paradigm in αβ T cell-mediated immunity is the simultaneous co-recognition of antigens and antigen-presenting molecules by the αβ T cell antigen receptor (TCR). CD1a presents a broad repertoire of lipid-based antigens. We found that a prototypical autoreactive TCR bound CD1a when it was presenting a series of permissive endogenous ligands, while other lipid ligands were nonpermissive to TCR binding. The structures of two TCR-CD1a-lipid complexes showed that the TCR docked over the A' roof of CD1a in a manner that precluded direct contact with permissive ligands. Nonpermissive ligands indirectly inhibited TCR binding by disrupting the TCR-CD1a contact zone. The exclusive recognition of CD1a by the TCR represents a previously unknown mechanism whereby αβ T cells indirectly sense self antigens that are bound to an antigen-presenting molecule.
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Affiliation(s)
- Richard W Birkinshaw
- 1] Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Australia. [2] ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Australia
| | - Daniel G Pellicci
- 1] Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia. [2] ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - Tan-Yun Cheng
- Brigham and Women's Hospital Division of Rheumatology, Immunology and Allergy and Harvard Medical School, Boston, Massachusetts, USA
| | - Andrew N Keller
- 1] Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Australia. [2] ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Australia
| | - Maria Sandoval-Romero
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Australia
| | - Stephanie Gras
- 1] Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Australia. [2] ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Australia
| | - Annemieke de Jong
- Department of Dermatology, Columbia University, New York, New York, USA
| | - Adam P Uldrich
- 1] Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia. [2] ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - D Branch Moody
- Brigham and Women's Hospital Division of Rheumatology, Immunology and Allergy and Harvard Medical School, Boston, Massachusetts, USA
| | - Dale I Godfrey
- 1] Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia. [2] ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - Jamie Rossjohn
- 1] Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Australia. [2] ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Australia. [3] Institute of Infection and Immunity, Cardiff University, School of Medicine, Heath Park, Cardiff, UK
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Walsh JT, Hendrix S, Boato F, Smirnov I, Zheng J, Lukens JR, Gadani S, Hechler D, Gölz G, Rosenberger K, Kammertöns T, Vogt J, Vogelaar C, Siffrin V, Radjavi A, Fernandez-Castaneda A, Gaultier A, Gold R, Kanneganti TD, Nitsch R, Zipp F, Kipnis J. MHCII-independent CD4+ T cells protect injured CNS neurons via IL-4. J Clin Invest 2015; 125:699-714. [PMID: 25607842 PMCID: PMC4319416 DOI: 10.1172/jci76210] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 12/02/2014] [Indexed: 12/13/2022] Open
Abstract
A body of experimental evidence suggests that T cells mediate neuroprotection following CNS injury; however, the antigen specificity of these T cells and how they mediate neuroprotection are unknown. Here, we have provided evidence that T cell-mediated neuroprotection after CNS injury can occur independently of major histocompatibility class II (MHCII) signaling to T cell receptors (TCRs). Using two murine models of CNS injury, we determined that damage-associated molecular mediators that originate from injured CNS tissue induce a population of neuroprotective, IL-4-producing T cells in an antigen-independent fashion. Compared with wild-type mice, IL-4-deficient animals had decreased functional recovery following CNS injury; however, transfer of CD4+ T cells from wild-type mice, but not from IL-4-deficient mice, enhanced neuronal survival. Using a culture-based system, we determined that T cell-derived IL-4 protects and induces recovery of injured neurons by activation of neuronal IL-4 receptors, which potentiated neurotrophin signaling via the AKT and MAPK pathways. Together, these findings demonstrate that damage-associated molecules from the injured CNS induce a neuroprotective T cell response that is independent of MHCII/TCR interactions and is MyD88 dependent. Moreover, our results indicate that IL-4 mediates neuroprotection and recovery of the injured CNS and suggest that strategies to enhance IL-4-producing CD4+ T cells have potential to attenuate axonal damage in the course of CNS injury in trauma, inflammation, or neurodegeneration.
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Affiliation(s)
- James T. Walsh
- Center for Brain Immunology and Glia
- Department of Neuroscience
- Graduate Program in Neuroscience, and
- Medical Scientist Training Program, School of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Sven Hendrix
- Department of Morphology and BIOMED Institute, Hasselt University, Diepenbeek, Belgium
- Institute for Cell Biology and Neurobiology, Center for Anatomy, Charité — Universitätsmedizin Berlin, Berlin, Germany
| | - Francesco Boato
- Institute for Cell Biology and Neurobiology, Center for Anatomy, Charité — Universitätsmedizin Berlin, Berlin, Germany
- Institute for Microscopic Anatomy and Neurobiology, Focus Program Translational Neuroscience, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Igor Smirnov
- Center for Brain Immunology and Glia
- Department of Neuroscience
| | - Jingjing Zheng
- Center for Brain Immunology and Glia
- Department of Neuroscience
- Institute of Neurosciences, Fourth Military Medical University, Xi’an, China
| | - John R. Lukens
- Center for Brain Immunology and Glia
- Department of Neuroscience
- Department of Immunology, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Sachin Gadani
- Center for Brain Immunology and Glia
- Department of Neuroscience
- Graduate Program in Neuroscience, and
- Medical Scientist Training Program, School of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Daniel Hechler
- Institute for Cell Biology and Neurobiology, Center for Anatomy, Charité — Universitätsmedizin Berlin, Berlin, Germany
| | - Greta Gölz
- Institute for Cell Biology and Neurobiology, Center for Anatomy, Charité — Universitätsmedizin Berlin, Berlin, Germany
| | - Karen Rosenberger
- Institute for Cell Biology and Neurobiology, Center for Anatomy, Charité — Universitätsmedizin Berlin, Berlin, Germany
| | | | - Johannes Vogt
- Institute for Cell Biology and Neurobiology, Center for Anatomy, Charité — Universitätsmedizin Berlin, Berlin, Germany
- Institute for Microscopic Anatomy and Neurobiology, Focus Program Translational Neuroscience, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Christina Vogelaar
- Institute for Microscopic Anatomy and Neurobiology, Focus Program Translational Neuroscience, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Volker Siffrin
- Department of Neurology, Focus Program Translational Neuroscience and Center for Immunotherapy, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Ali Radjavi
- Center for Brain Immunology and Glia
- Department of Neuroscience
- Graduate Program in Microbiology, Immunology and Infectious Diseases, School of Medicine, University of Virginia, Charlottesville, Virginia, USA
| | | | - Alban Gaultier
- Center for Brain Immunology and Glia
- Department of Neuroscience
- Graduate Program in Neuroscience, and
| | - Ralf Gold
- Department of Neurology, St. Josef Hospital/Ruhr-University Bochum, Bochum, Germany
| | | | - Robert Nitsch
- Institute for Cell Biology and Neurobiology, Center for Anatomy, Charité — Universitätsmedizin Berlin, Berlin, Germany
- Institute for Microscopic Anatomy and Neurobiology, Focus Program Translational Neuroscience, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Frauke Zipp
- Department of Neurology, Focus Program Translational Neuroscience and Center for Immunotherapy, University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Jonathan Kipnis
- Center for Brain Immunology and Glia
- Department of Neuroscience
- Graduate Program in Neuroscience, and
- Medical Scientist Training Program, School of Medicine, University of Virginia, Charlottesville, Virginia, USA
- Graduate Program in Microbiology, Immunology and Infectious Diseases, School of Medicine, University of Virginia, Charlottesville, Virginia, USA
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Abstract
During blood cell development, hematopoietic stem cells generate diverse mature populations via several rounds of binary fate decisions. At each bifurcation, precursors adopt one fate and inactivate the alternative fate either stochastically or in response to extrinsic stimuli and stably maintain the selected fates. Studying of these processes would contribute to better understanding of etiology of immunodeficiency and leukemia, which are caused by abnormal gene regulation during the development of hematopoietic cells. The CD4(+) helper versus CD8(+) cytotoxic T-cell fate decision serves as an excellent model to study binary fate decision processes. These two cell types are derived from common precursors in the thymus. Positive selection of their TCRs by self-peptide presented on either MHC class I or class II triggers their fate decisions along with mutually exclusive retention and silencing of two coreceptors, CD4 and CD8. In the past few decades, extensive effort has been made to understand the T-cell fate decision processes by studying regulation of genes encoding the coreceptors and selection processes. These studies have identified several key transcription factors and gene regulatory networks. In this chapter, I will discuss recent advances in our understanding of the binary cell fate decision processes of T cells.
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Affiliation(s)
- Takeshi Egawa
- Department of Pathology and Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA.
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49
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Rossjohn J, Gras S, Miles JJ, Turner SJ, Godfrey DI, McCluskey J. T cell antigen receptor recognition of antigen-presenting molecules. Annu Rev Immunol 2014; 33:169-200. [PMID: 25493333 DOI: 10.1146/annurev-immunol-032414-112334] [Citation(s) in RCA: 508] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The Major Histocompatibility Complex (MHC) locus encodes classical MHC class I and MHC class II molecules and nonclassical MHC-I molecules. The architecture of these molecules is ideally suited to capture and present an array of peptide antigens (Ags). In addition, the CD1 family members and MR1 are MHC class I-like molecules that bind lipid-based Ags and vitamin B precursors, respectively. These Ag-bound molecules are subsequently recognized by T cell antigen receptors (TCRs) expressed on the surface of T lymphocytes. Structural and associated functional studies have been highly informative in providing insight into these interactions, which are crucial to immunity, and how they can lead to aberrant T cell reactivity. Investigators have determined over thirty unique TCR-peptide-MHC-I complex structures and twenty unique TCR-peptide-MHC-II complex structures. These investigations have shown a broad consensus in docking geometry and provided insight into MHC restriction. Structural studies on TCR-mediated recognition of lipid and metabolite Ags have been mostly confined to TCRs from innate-like natural killer T cells and mucosal-associated invariant T cells, respectively. These studies revealed clear differences between TCR-lipid-CD1, TCR-metabolite-MR1, and TCR-peptide-MHC recognition. Accordingly, TCRs show remarkable structural and biological versatility in engaging different classes of Ag that are presented by polymorphic and monomorphic Ag-presenting molecules of the immune system.
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Affiliation(s)
- Jamie Rossjohn
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia; ,
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50
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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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