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Jenkins E, Körbel M, O'Brien-Ball C, McColl J, Chen KY, Kotowski M, Humphrey J, Lippert AH, Brouwer H, Santos AM, Lee SF, Davis SJ, Klenerman D. Antigen discrimination by T cells relies on size-constrained microvillar contact. Nat Commun 2023; 14:1611. [PMID: 36959206 PMCID: PMC10036606 DOI: 10.1038/s41467-023-36855-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 02/21/2023] [Indexed: 03/25/2023] Open
Abstract
T cells use finger-like protrusions called 'microvilli' to interrogate their targets, but why they do so is unknown. To form contacts, T cells must overcome the highly charged, barrier-like layer of large molecules forming a target cell's glycocalyx. Here, T cells are observed to use microvilli to breach a model glycocalyx barrier, forming numerous small (<0.5 μm diameter) contacts each of which is stabilized by the small adhesive protein CD2 expressed by the T cell, and excludes large proteins including CD45, allowing sensitive, antigen dependent TCR signaling. In the absence of the glycocalyx or when microvillar contact-size is increased by enhancing CD2 expression, strong signaling occurs that is no longer antigen dependent. Our observations suggest that, modulated by the opposing effects of the target cell glycocalyx and small adhesive proteins, the use of microvilli equips T cells with the ability to effect discriminatory receptor signaling.
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Affiliation(s)
- Edward Jenkins
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- Medical Research Council Human Immunology Unit, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Markus Körbel
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Caitlin O'Brien-Ball
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- Medical Research Council Human Immunology Unit, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - James McColl
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Kevin Y Chen
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Mateusz Kotowski
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- Medical Research Council Human Immunology Unit, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Jane Humphrey
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Anna H Lippert
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Heather Brouwer
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- Medical Research Council Human Immunology Unit, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Ana Mafalda Santos
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- Medical Research Council Human Immunology Unit, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Steven F Lee
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Simon J Davis
- Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK.
- Medical Research Council Human Immunology Unit, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK.
| | - David Klenerman
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
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2
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Waldman MM, Rahkola JT, Sigler AL, Chung JW, Willett BAS, Kedl RM, Friedman RS, Jacobelli J. Ena/VASP Protein-Mediated Actin Polymerization Contributes to Naïve CD8 + T Cell Activation and Expansion by Promoting T Cell-APC Interactions In Vivo. Front Immunol 2022; 13:856977. [PMID: 35757762 PMCID: PMC9222560 DOI: 10.3389/fimmu.2022.856977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 04/28/2022] [Indexed: 11/13/2022] Open
Abstract
Naïve T cell activation in secondary lymphoid organs such as lymph nodes (LNs) occurs upon recognition of cognate antigen presented by antigen presenting cells (APCs). T cell activation requires cytoskeleton rearrangement and sustained interactions with APCs. Enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) proteins are a family of cytoskeletal effector proteins responsible for actin polymerization and are frequently found at the leading edge of motile cells. Ena/VASP proteins have been implicated in motility and adhesion in various cell types, but their role in primary T cell interstitial motility and activation has not been explored. Our goal was to determine the contribution of Ena/VASP proteins to T cell–APC interactions, T cell activation, and T cell expansion in vivo. Our results showed that naïve T cells from Ena/VASP-deficient mice have a significant reduction in antigen-specific T cell accumulation following Listeria monocytogenes infection. The kinetics of T cell expansion impairment were further confirmed in Ena/VASP-deficient T cells stimulated via dendritic cell immunization. To investigate the cause of this T cell expansion defect, we analyzed T cell–APC interactions in vivo by two-photon microscopy and observed fewer Ena/VASP-deficient naïve T cells interacting with APCs in LNs during priming. We also determined that Ena/VASP-deficient T cells formed conjugates with significantly less actin polymerization at the T cell–APC synapse, and that these conjugates were less stable than their WT counterparts. Finally, we found that Ena/VASP-deficient T cells have less LFA-1 polarized to the T cell–APC synapse. Thus, we conclude that Ena/VASP proteins contribute to T cell actin remodeling during T cell–APC interactions, which promotes the initiation of stable T cell conjugates during APC scanning. Therefore, Ena/VASP proteins are required for efficient activation and expansion of T cells in vivo.
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Affiliation(s)
- Monique M Waldman
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Barbara Davis Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Jeremy T Rahkola
- Rocky Mountain Regional Veterans Affairs (VA) Medical Center, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Ashton L Sigler
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Barbara Davis Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Jeffrey W Chung
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Barbara Davis Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Benjamin A S Willett
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Ross M Kedl
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Rachel S Friedman
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Barbara Davis Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Jordan Jacobelli
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Barbara Davis Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO, United States
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3
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Sadoun A, Biarnes-Pelicot M, Ghesquiere-Dierickx L, Wu A, Théodoly O, Limozin L, Hamon Y, Puech PH. Controlling T cells spreading, mechanics and activation by micropatterning. Sci Rep 2021; 11:6783. [PMID: 33762632 PMCID: PMC7991639 DOI: 10.1038/s41598-021-86133-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/02/2021] [Indexed: 01/31/2023] Open
Abstract
We designed a strategy, based on a careful examination of the activation capabilities of proteins and antibodies used as substrates for adhering T cells, coupled to protein microstamping to control at the same time the position, shape, spreading, mechanics and activation state of T cells. Once adhered on patterns, we examined the capacities of T cells to be activated with soluble anti CD3, in comparison to T cells adhered to a continuously decorated substrate with the same density of ligands. We show that, in our hand, adhering onto an anti CD45 antibody decorated surface was not affecting T cell calcium fluxes, even adhered on variable size micro-patterns. Aside, we analyzed the T cell mechanics, when spread on pattern or not, using Atomic Force Microscopy indentation. By expressing MEGF10 as a non immune adhesion receptor in T cells we measured the very same spreading area on PLL substrates and Young modulus than non modified cells, immobilized on anti CD45 antibodies, while retaining similar activation capabilities using soluble anti CD3 antibodies or through model APC contacts. We propose that our system is a way to test activation or anergy of T cells with defined adhesion and mechanical characteristics, and may allow to dissect fine details of these mechanisms since it allows to observe homogenized populations in standardized T cell activation assays.
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Affiliation(s)
- Anaïs Sadoun
- grid.5399.60000 0001 2176 4817Adhesion and Inflammation Lab (LAI), Aix Marseille University, LAI UM 61, 13288 Marseille, France ,grid.457381.cAdhesion and Inflammation Lab (LAI), Inserm, UMR_S 1067, 13288 Marseille, France ,grid.4444.00000 0001 2112 9282Adhesion and Inflammation Lab (LAI), CNRS, UMR 7333, 13288 Marseille, France ,grid.5399.60000 0001 2176 4817Centre d’Immunologie de Marseille Luminy (CIML), Aix-Marseille University, CNRS, Inserm, CIML Marseille, 13288 Marseille, France
| | - Martine Biarnes-Pelicot
- grid.5399.60000 0001 2176 4817Adhesion and Inflammation Lab (LAI), Aix Marseille University, LAI UM 61, 13288 Marseille, France ,grid.457381.cAdhesion and Inflammation Lab (LAI), Inserm, UMR_S 1067, 13288 Marseille, France ,grid.4444.00000 0001 2112 9282Adhesion and Inflammation Lab (LAI), CNRS, UMR 7333, 13288 Marseille, France
| | - Laura Ghesquiere-Dierickx
- grid.5399.60000 0001 2176 4817Adhesion and Inflammation Lab (LAI), Aix Marseille University, LAI UM 61, 13288 Marseille, France ,grid.457381.cAdhesion and Inflammation Lab (LAI), Inserm, UMR_S 1067, 13288 Marseille, France ,grid.4444.00000 0001 2112 9282Adhesion and Inflammation Lab (LAI), CNRS, UMR 7333, 13288 Marseille, France ,grid.7497.d0000 0004 0492 0584Present Address: Division of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ambroise Wu
- grid.5399.60000 0001 2176 4817Centre d’Immunologie de Marseille Luminy (CIML), Aix-Marseille University, CNRS, Inserm, CIML Marseille, 13288 Marseille, France ,grid.8505.80000 0001 1010 5103Present Address: Department of Biophysics, University of Wrocław, Wrocław, Poland
| | - Olivier Théodoly
- grid.5399.60000 0001 2176 4817Adhesion and Inflammation Lab (LAI), Aix Marseille University, LAI UM 61, 13288 Marseille, France ,grid.457381.cAdhesion and Inflammation Lab (LAI), Inserm, UMR_S 1067, 13288 Marseille, France ,grid.4444.00000 0001 2112 9282Adhesion and Inflammation Lab (LAI), CNRS, UMR 7333, 13288 Marseille, France
| | - Laurent Limozin
- grid.5399.60000 0001 2176 4817Adhesion and Inflammation Lab (LAI), Aix Marseille University, LAI UM 61, 13288 Marseille, France ,grid.457381.cAdhesion and Inflammation Lab (LAI), Inserm, UMR_S 1067, 13288 Marseille, France ,grid.4444.00000 0001 2112 9282Adhesion and Inflammation Lab (LAI), CNRS, UMR 7333, 13288 Marseille, France
| | - Yannick Hamon
- grid.5399.60000 0001 2176 4817Centre d’Immunologie de Marseille Luminy (CIML), Aix-Marseille University, CNRS, Inserm, CIML Marseille, 13288 Marseille, France
| | - Pierre-Henri Puech
- grid.5399.60000 0001 2176 4817Adhesion and Inflammation Lab (LAI), Aix Marseille University, LAI UM 61, 13288 Marseille, France ,grid.457381.cAdhesion and Inflammation Lab (LAI), Inserm, UMR_S 1067, 13288 Marseille, France ,grid.4444.00000 0001 2112 9282Adhesion and Inflammation Lab (LAI), CNRS, UMR 7333, 13288 Marseille, France
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4
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CD8 Co-Receptor Enhances T-Cell Activation without Any Effect on Initial Attachment. Cells 2021; 10:cells10020429. [PMID: 33670573 PMCID: PMC7922487 DOI: 10.3390/cells10020429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/11/2021] [Accepted: 02/13/2021] [Indexed: 12/27/2022] Open
Abstract
The scanning of surrounding tissues by T lymphocytes to detect cognate antigens requires high speed, sensitivity and specificity. T-cell receptor (TCR) co-receptors such as CD8 increase detection performance, but the exact mechanism remains incompletely understood. Here, we used a laminar flow chamber to measure at the single molecule level the kinetics of bond formation and rupture between TCR- transfected CD8+ and CD8− Jurkat cells and surfaces coated with five peptide-exposing major histocompatibility antigens (pMHCs) of varying activating power. We also used interference reflection microscopy to image the spreading of these cells dropped on pMHC-exposing surfaces. CD8 did not influence the TCR–pMHC interaction during the first few seconds following cell surface encounter, but it promoted the subsequent spreading responses, suggesting that CD8 was involved in early activation rather than binding. Further, the rate and extent of spreading, but not the lag between contact and spreading initiation, depended on the pMHC. Elucidating T-lymphocyte detection strategy may help unravel underlying signaling networks.
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5
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Rushdi M, Li K, Yuan Z, Travaglino S, Grakoui A, Zhu C. Mechanotransduction in T Cell Development, Differentiation and Function. Cells 2020; 9:E364. [PMID: 32033255 PMCID: PMC7072571 DOI: 10.3390/cells9020364] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 02/07/2023] Open
Abstract
Cells in the body are actively engaging with their environments that include both biochemical and biophysical aspects. The process by which cells convert mechanical stimuli from their environment to intracellular biochemical signals is known as mechanotransduction. Exemplifying the reliance on mechanotransduction for their development, differentiation and function are T cells, which are central to adaptive immune responses. T cell mechanoimmunology is an emerging field that studies how T cells sense, respond and adapt to the mechanical cues that they encounter throughout their life cycle. Here we review different stages of the T cell's life cycle where existing studies have shown important effects of mechanical force or matrix stiffness on a T cell as sensed through its surface molecules, including modulating receptor-ligand interactions, inducing protein conformational changes, triggering signal transduction, amplifying antigen discrimination and ensuring directed targeted cell killing. We suggest that including mechanical considerations in the immunological studies of T cells would inform a more holistic understanding of their development, differentiation and function.
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Affiliation(s)
- Muaz Rushdi
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; (M.R.); (K.L.); (S.T.)
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA;
| | - Kaitao Li
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; (M.R.); (K.L.); (S.T.)
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA;
| | - Zhou Yuan
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA;
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30313, USA
| | - Stefano Travaglino
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; (M.R.); (K.L.); (S.T.)
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA;
| | - Arash Grakoui
- Emory Vaccine Center, Division of Microbiology and Immunology, Yerkes Research Primate Center, Emory University School of Medicine, Atlanta, GA 30329, USA;
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Cheng Zhu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; (M.R.); (K.L.); (S.T.)
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA;
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30313, USA
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6
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Biphasic mechanosensitivity of T cell receptor-mediated spreading of lymphocytes. Proc Natl Acad Sci U S A 2019; 116:5908-5913. [PMID: 30850545 DOI: 10.1073/pnas.1811516116] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Mechanosensing by T cells through the T cell receptor (TCR) is at the heart of immune recognition. While the mechanobiology of the TCR at the molecular level is increasingly well documented, its link to cell-scale response is poorly understood. Here we explore T cell spreading response as a function of substrate rigidity and show that remarkably, depending on the surface receptors stimulated, the cellular response may be either biphasic or monotonous. When adhering solely via the TCR complex, T cells respond to environmental stiffness in an unusual fashion, attaining maximal spreading on an optimal substrate stiffness comparable to that of professional antigen-presenting cells. However, in the presence of additional ligands for the integrin LFA-1, this biphasic response is abrogated and the cell spreading increases monotonously with stiffness up to a saturation value. This ligand-specific mechanosensing is effected through an actin-polymerization-dependent mechanism. We construct a mesoscale semianalytical model based on force-dependent bond rupture and show that cell-scale biphasic or monotonous behavior emerges from molecular parameters. As the substrate stiffness is increased, there is a competition between increasing effective stiffness of the bonds, which leads to increased cell spreading and increasing bond breakage, which leads to decreased spreading. We hypothesize that the link between actin and the receptors (TCR or LFA-1), rather than the ligand/receptor linkage, is the site of this mechanosensing.
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7
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Ng SS, Engwerda CR. Innate Lymphocytes and Malaria - Players or Spectators? Trends Parasitol 2018; 35:154-162. [PMID: 30579700 DOI: 10.1016/j.pt.2018.11.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/29/2018] [Accepted: 11/29/2018] [Indexed: 12/19/2022]
Abstract
Malaria remains an important global disease. Despite significant advances over the past decade in reducing disease morbidity and mortality, new measures are needed if malaria is to be eliminated. Significant advances in our understanding about host immune responses during malaria have been made, opening up opportunities to generate long-lasting antiparasitic immunity through vaccination or immune therapy. However, there is still much debate over which immune cell populations contribute to immunity to malaria, including innate lymphocytes that comprise recently identified innate lymphoid cells (ILCs) and better known innate-like T cell subsets. Here, we review research on these immune cell subsets and discuss whether they have any important roles in immunity to malaria or if they are redundant.
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Affiliation(s)
- Susanna S Ng
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, QLD, Australia; School of Environment and Science, Griffith University, QLD, Australia
| | - Christian R Engwerda
- Immunology and Infection Laboratory, QIMR Berghofer Medical Research Institute, QLD, Australia.
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8
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Saitakis M, Dogniaux S, Goudot C, Bufi N, Asnacios S, Maurin M, Randriamampita C, Asnacios A, Hivroz C. Different TCR-induced T lymphocyte responses are potentiated by stiffness with variable sensitivity. eLife 2017; 6. [PMID: 28594327 PMCID: PMC5464771 DOI: 10.7554/elife.23190] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 05/07/2017] [Indexed: 12/26/2022] Open
Abstract
T cells are mechanosensitive but the effect of stiffness on their functions is still debated. We characterize herein how human primary CD4+ T cell functions are affected by stiffness within the physiological Young’s modulus range of 0.5 kPa to 100 kPa. Stiffness modulates T lymphocyte migration and morphological changes induced by TCR/CD3 triggering. Stiffness also increases TCR-induced immune system, metabolism and cell-cycle-related genes. Yet, upon TCR/CD3 stimulation, while cytokine production increases within a wide range of stiffness, from hundreds of Pa to hundreds of kPa, T cell metabolic properties and cell cycle progression are only increased by the highest stiffness tested (100 kPa). Finally, mechanical properties of adherent antigen-presenting cells modulate cytokine production by T cells. Together, these results reveal that T cells discriminate between the wide range of stiffness values found in the body and adapt their responses accordingly. DOI:http://dx.doi.org/10.7554/eLife.23190.001 Our immune system contains many cells that play various roles in defending the body against infection, cancer and other threats. For example, T cells constantly patrol the body ready to detect and respond to dangers. They do so by gathering cues from their surroundings, which can be specific chemical signals or physical properties such as the stiffness of tissues. Once the T cells are active they respond in several different ways including releasing hormones and dividing to produce more T cells. Tissue stiffness varies considerably between different organs. Furthermore, disease can lead to changes in tissue stiffness. For example, tissues become more rigid when they are inflamed. The stiffness and other physical properties of the surfaces that T cells interact with affect how the cells respond when they detect a threat, but few details are known about exactly how these cues tune T cell responses. Saitakis et al. studied how human T cells respond to artificial surfaces of varying stiffness that mimic the range found in the body. The experiments show that T cells that interact with stiff surfaces become more active than T cells that interact with softer surfaces. However, some responses are more sensitive to the stiffness of the surface than others. For example, the ability of the T cells to release hormones was affected by the whole range of stiffnesses tested in the experiments, whereas only very stiff surfaces stimulated the T cells to divide. These findings show that T cells can detect the stiffness of surfaces in the body and use this to adapt how they respond to threats. Future challenges will be to find out how T cells sense the physical properties of their surroundings and investigate whether cell and tissue stiffness affects immune responses in the body. This will help us to understand how T cells fight infections and other threats, and could be used to develop new ways of boosting these cells to fight cancer and other diseases. DOI:http://dx.doi.org/10.7554/eLife.23190.002
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Affiliation(s)
- Michael Saitakis
- Institut Curie Section Recherche, INSERM U932 & PSL Research University, Paris, France
| | - Stéphanie Dogniaux
- Institut Curie Section Recherche, INSERM U932 & PSL Research University, Paris, France
| | - Christel Goudot
- Institut Curie Section Recherche, INSERM U932 & PSL Research University, Paris, France
| | - Nathalie Bufi
- Laboratoire Matières et systèmes complexes, Université Paris-Diderot and CNRS, UMR 7057, Sorbonne Paris Cité, Paris, France
| | - Sophie Asnacios
- Laboratoire Matières et systèmes complexes, Université Paris-Diderot and CNRS, UMR 7057, Sorbonne Paris Cité, Paris, France.,Department of Physics, Sorbonne Universités, UPMC Université Paris, Paris, France
| | - Mathieu Maurin
- Institut Curie Section Recherche, INSERM U932 & PSL Research University, Paris, France
| | - Clotilde Randriamampita
- INSERM, U1016, Institut Cochin & UMR8104, CNRS & Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Atef Asnacios
- Laboratoire Matières et systèmes complexes, Université Paris-Diderot and CNRS, UMR 7057, Sorbonne Paris Cité, Paris, France
| | - Claire Hivroz
- Institut Curie Section Recherche, INSERM U932 & PSL Research University, Paris, France
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9
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Shorter SK, Schnell FJ, McMaster SR, Pinelli DF, Andargachew R, Evavold BD. Viral Escape Mutant Epitope Maintains TCR Affinity for Antigen yet Curtails CD8 T Cell Responses. PLoS One 2016; 11:e0149582. [PMID: 26915099 PMCID: PMC4767940 DOI: 10.1371/journal.pone.0149582] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/01/2016] [Indexed: 12/03/2022] Open
Abstract
T cells have the remarkable ability to recognize antigen with great specificity and in turn mount an appropriate and robust immune response. Critical to this process is the initial T cell antigen recognition and subsequent signal transduction events. This antigen recognition can be modulated at the site of TCR interaction with peptide:major histocompatibility (pMHC) or peptide interaction with the MHC molecule. Both events could have a range of effects on T cell fate. Though responses to antigens that bind sub-optimally to TCR, known as altered peptide ligands (APL), have been studied extensively, the impact of disrupting antigen binding to MHC has been highlighted to a lesser extent and is usually considered to result in complete loss of epitope recognition. Here we present a model of viral evasion from CD8 T cell immuno-surveillance by a lymphocytic choriomeningitis virus (LCMV) escape mutant with an epitope for which TCR affinity for pMHC remains high but where the antigenic peptide binds sub optimally to MHC. Despite high TCR affinity for variant epitope, levels of interferon regulatory factor-4 (IRF4) are not sustained in response to the variant indicating differences in perceived TCR signal strength. The CD8+ T cell response to the variant epitope is characterized by early proliferation and up-regulation of activation markers. Interestingly, this response is not maintained and is characterized by a lack in IL-2 and IFNγ production, increased apoptosis and an abrogated glycolytic response. We show that disrupting the stability of peptide in MHC can effectively disrupt TCR signal strength despite unchanged affinity for TCR and can significantly impact the CD8+ T cell response to a viral escape mutant.
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Affiliation(s)
- Shayla K. Shorter
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, United States of America
| | - Frederick J. Schnell
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, United States of America
| | - Sean R. McMaster
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, United States of America
| | - David F. Pinelli
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, United States of America
| | - Rakieb Andargachew
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, United States of America
| | - Brian D. Evavold
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, United States of America
- * E-mail:
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