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Carré A, Zhou Z, Perez-Hernandez J, Samassa F, Lekka C, Manganaro A, Oshima M, Liao H, Parker R, Nicastri A, Brandao B, Colli ML, Eizirik DL, Göransson M, Morales OB, Anderson A, Landry L, Kobaisi F, Scharfmann R, Marselli L, Marchetti P, You S, Nakayama M, Hadrup SR, Kent SC, Richardson SJ, Ternette N, Mallone R. Interferon-α promotes neo-antigen formation and preferential HLA-B-restricted antigen presentation in pancreatic β-cells. bioRxiv 2023:2023.09.15.557918. [PMID: 37745505 PMCID: PMC10516036 DOI: 10.1101/2023.09.15.557918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Interferon (IFN)-α is the earliest cytokine signature observed in individuals at risk for type 1 diabetes (T1D), but its effect on the repertoire of HLA Class I (HLA-I)-bound peptides presented by pancreatic β-cells is unknown. Using immunopeptidomics, we characterized the peptide/HLA-I presentation in in-vitro resting and IFN-α-exposed β-cells. IFN-α increased HLA-I expression and peptide presentation, including neo-sequences derived from alternative mRNA splicing, post-translational modifications - notably glutathionylation - and protein cis-splicing. This antigenic landscape relied on processing by both the constitutive and immune proteasome. The resting β-cell immunopeptidome was dominated by HLA-A-restricted ligands. However, IFN-α only marginally upregulated HLA-A and largely favored HLA-B, translating into a major increase in HLA-B-restricted peptides and into an increased activation of HLA-B-restricted vs. HLA-A-restricted CD8+ T-cells. A preferential HLA-B hyper-expression was also observed in the islets of T1D vs. non-diabetic donors, and we identified islet-infiltrating CD8+ T-cells from T1D donors reactive to HLA-B-restricted granule peptides. Thus, the inflammatory milieu of insulitis may skew the autoimmune response toward epitopes presented by HLA-B, hence recruiting a distinct T-cell repertoire that may be relevant to T1D pathogenesis.
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Affiliation(s)
- Alexia Carré
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Zhicheng Zhou
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Javier Perez-Hernandez
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Department of Nutrition and Health, Valencian International University (VIU), Valencia, Spain
| | | | - Christiana Lekka
- Islet Biology Group, Exeter Centre of Excellence in Diabetes Research, University of Exeter Medical School, Exeter, UK
| | - Anthony Manganaro
- Diabetes Center of Excellence, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Masaya Oshima
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Hanqing Liao
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Robert Parker
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Annalisa Nicastri
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Barbara Brandao
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Maikel L. Colli
- ULB Center for Diabetes Research, Université Libre de Bruxelles, Brussels, Belgium
| | - Decio L. Eizirik
- ULB Center for Diabetes Research, Université Libre de Bruxelles, Brussels, Belgium
| | - Marcus Göransson
- Department of Health Technology, Technical University of Denmark, Copenhagen, Denmark
| | | | - Amanda Anderson
- Barbara Davis Center for Diabetes, University of Colorado School of Medicine, Aurora, CO, USA
| | - Laurie Landry
- Barbara Davis Center for Diabetes, University of Colorado School of Medicine, Aurora, CO, USA
| | - Farah Kobaisi
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | | | - Lorella Marselli
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Piero Marchetti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Sylvaine You
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Maki Nakayama
- Barbara Davis Center for Diabetes, University of Colorado School of Medicine, Aurora, CO, USA
| | - Sine R. Hadrup
- Department of Health Technology, Technical University of Denmark, Copenhagen, Denmark
| | - Sally C. Kent
- Diabetes Center of Excellence, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Sarah J. Richardson
- Islet Biology Group, Exeter Centre of Excellence in Diabetes Research, University of Exeter Medical School, Exeter, UK
| | - Nicola Ternette
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Roberto Mallone
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
- Assistance Publique Hôpitaux de Paris, Service de Diabétologie et Immunologie Clinique, Cochin Hospital, Paris, France
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Abstract
PURPOSE OF REVIEW Recent work using immunopeptidomics and deconvolution of the antigenic reactivity of islet-infiltrating CD8+ T cells has expanded our knowledge about the autoimmune target epitopes of type 1 diabetes. The stem-like properties of autoimmune CD8+ T cells have also been described. We here propose a possible link between these findings. RECENT FINDINGS Weak major histocompatibility complex (MHC)-binding epitopes list among the major targets of human islet-infiltrating CD8+ T cells, likely resulting in low peptide-MHC presentation that delivers weak T-cell receptor (TCR) signals, especially in the face of low-affinity autoimmune TCRs. These weak TCR signals may favor the maintenance of the partially differentiated stem-like phenotype recently described for islet-reactive CD8+ T cells in the blood and pancreatic lymph nodes. These weak TCR signals may also be physiological, reflecting the need for self-peptide-MHC contacts to maintain homeostatic T-cell survival and proliferation. These features may underlie the universal state of benign autoimmunity that we recently described, which is characterized by islet-reactive, naïve-like CD8+ T cells circulating in all individuals. SUMMARY These observations provide novel challenges and opportunities to develop circulating T-cell biomarkers for autoimmune staging. Therapeutic halting of islet autoimmunity may require targeting of stem-like T cells to blunt their self-regeneration.
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Affiliation(s)
| | - Roberto Mallone
- Institut Cochin, Université Paris Cité, CNRS, INSERM
- Assistance Publique Hôpitaux de Paris, Service de Diabétologie et Immunologie Clinique, Cochin Hospital, Paris, France
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Azoury ME, Samassa F, Buitinga M, Nigi L, Brusco N, Callebaut A, Giraud M, Irla M, Lalanne AI, Carré A, Afonso G, Zhou Z, Brandao B, Colli ML, Sebastiani G, Dotta F, Nakayama M, Eizirik DL, You S, Pinto S, Mamula MJ, Verdier Y, Vinh J, Buus S, Mathieu C, Overbergh L, Mallone R. CD8 + T Cells Variably Recognize Native Versus Citrullinated GRP78 Epitopes in Type 1 Diabetes. Diabetes 2021; 70:2879-2891. [PMID: 34561224 PMCID: PMC8660990 DOI: 10.2337/db21-0259] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 09/17/2021] [Indexed: 11/13/2022]
Abstract
In type 1 diabetes, autoimmune β-cell destruction may be favored by neoantigens harboring posttranslational modifications (PTMs) such as citrullination. We studied the recognition of native and citrullinated glucose-regulated protein (GRP)78 peptides by CD8+ T cells. Citrullination modulated T-cell recognition and, to a lesser extent, HLA-A2 binding. GRP78-reactive CD8+ T cells circulated at similar frequencies in healthy donors and donors with type 1 diabetes and preferentially recognized either native or citrullinated versions, without cross-reactivity. Rather, the preference for native GRP78 epitopes was associated with CD8+ T cells cross-reactive with bacterial mimotopes. In the pancreas, a dominant GRP78 peptide was instead preferentially recognized when citrullinated. To further clarify these recognition patterns, we considered the possibility of citrullination in the thymus. Citrullinating peptidylarginine deiminase (Padi) enzymes were expressed in murine and human medullary epithelial cells (mTECs), with citrullinated proteins detected in murine mTECs. However, Padi2 and Padi4 expression was diminished in mature mTECs from NOD mice versus C57BL/6 mice. We conclude that, on one hand, the CD8+ T cell preference for native GRP78 peptides may be shaped by cross-reactivity with bacterial mimotopes. On the other hand, PTMs may not invariably favor loss of tolerance because thymic citrullination, although impaired in NOD mice, may drive deletion of citrulline-reactive T cells.
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Affiliation(s)
| | | | - Mijke Buitinga
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Laura Nigi
- Toscana Life Sciences, Diabetes Unit and Fondazione Umberto di Mario ONLUS, Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Noemi Brusco
- Toscana Life Sciences, Diabetes Unit and Fondazione Umberto di Mario ONLUS, Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Aïsha Callebaut
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Matthieu Giraud
- Centre de Recherche en Transplantation et Immunologie, INSERM UMR1064, Université de Nantes, Nantes, France
| | - Magali Irla
- Centre d'Immunologie de Marseille-Luminy, INSERM, CNRS, Aix-Marseille University, Marseille, France
| | - Ana Ines Lalanne
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Alexia Carré
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Georgia Afonso
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Zhicheng Zhou
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Barbara Brandao
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Maikel L Colli
- Medical Faculty, Center for Diabetes Research and Welbio, Université Libre de Bruxelles, Brussels, Belgium
| | - Guido Sebastiani
- Toscana Life Sciences, Diabetes Unit and Fondazione Umberto di Mario ONLUS, Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Francesco Dotta
- Toscana Life Sciences, Diabetes Unit and Fondazione Umberto di Mario ONLUS, Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Maki Nakayama
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Decio L Eizirik
- Medical Faculty, Center for Diabetes Research and Welbio, Université Libre de Bruxelles, Brussels, Belgium
- Indiana Biosciences Research Institute, Indianapolis, IN
| | - Sylvaine You
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Sheena Pinto
- Division of Developmental Immunology, Deutsches Krebsforschungszentrum, Heidelberg, Germany
| | | | - Yann Verdier
- ESPCI Paris, PSL University, Spectrométrie de Masse Biologique et Protéomique, CNRS UMR8249, Paris, France
| | - Joelle Vinh
- ESPCI Paris, PSL University, Spectrométrie de Masse Biologique et Protéomique, CNRS UMR8249, Paris, France
| | - Soren Buus
- Department of International Health, Immunology and Microbiology, Panum Institute, Copenhagen, Denmark
| | - Chantal Mathieu
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Lut Overbergh
- Laboratory of Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Roberto Mallone
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
- Assistance Publique Hôpitaux de Paris, Service de Diabétologie et Immunologie Clinique, Cochin Hospital, Paris, France
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Grego L, Pignatto S, Alfier F, Arigliani M, Rizzetto F, Rassu N, Samassa F, Prosperi R, Barbieri F, Dall'Amico R, Cogo P, Lanzetta P. Optical coherence tomography (OCT) and OCT angiography allow early identification of sickle cell maculopathy in children and correlate it with systemic risk factors. Graefes Arch Clin Exp Ophthalmol 2020; 258:2551-2561. [PMID: 32518974 DOI: 10.1007/s00417-020-04764-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 05/13/2020] [Accepted: 05/20/2020] [Indexed: 10/24/2022] Open
Abstract
PURPOSE To determine the presence of sickle cell retinopathy and maculopathy and to identify associations between markers of hemolysis and systemic and ocular manifestations in children affected by sickle cell disease. METHODS Eighteen children with sickle cell disease, aged 5-16 years, underwent complete eye examination including best-corrected visual acuity, slit-lamp biomicroscopy, ophthalmoscopy after pharmacological mydriasis, spectral-domain optical coherence tomography (SD-OCT), and optical coherence tomography angiography (OCTA). Blood test results and clinical history information were collected for each child, including fetal hemoglobin (HbF), hemoglobin (Hb), hematocrit (Htc), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), reticulocytes percentage (%ret), lactic dehydrogenase (LDH), total and direct bilirubin, glomerular filtration rate, number of painful crises, acute chest syndromes, and splenic sequestration. Therapeutic regimen and transfusion therapy were also evaluated. RESULTS Sixteen of 36 eyes (44.4%) had non-proliferative sickle cell retinopathy on ophthalmoscopic evaluation. No patients had proliferative sickle cell retinopathy. In 13 of 36 eyes (36.1%), SD-OCT and OCTA detected signs of sickle cell maculopathy. Nine eyes (25%) presented sickle cell retinopathy and maculopathy, 7 eyes (19.4%) sickle cell retinopathy alone, and 4 eyes (11.1%) sickle cell maculopathy alone. A statistically significant association was found between sickle cell retinopathy; lower levels of HbF, Hb, and Htc; and higher MCV and percentage of reticulocytes. Sickle cell maculopathy was associated with lower values of H and Htc and higher levels of reticulocytes and total bilirubin. CONCLUSIONS We identified early signs of sickle cell retinopathy and maculopathy in a pediatric population with SD-OCT and OCTA. These two retinal complications were more frequent in children with higher hemolytic rates.
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Affiliation(s)
- L Grego
- Department of Medicine- Ophthalmology, University of Udine, Udine, Italy
| | - S Pignatto
- Department of Medicine- Ophthalmology, University of Udine, Udine, Italy
| | - F Alfier
- Department of Medicine- Ophthalmology, University of Udine, Udine, Italy
| | - M Arigliani
- Department of Medicine- Paediatrics, University of Udine, Udine, Italy
| | - F Rizzetto
- Department of Ophthalmology, Hospital of Pordenone, Pordenone, Italy
| | - N Rassu
- Department of Medicine- Ophthalmology, University of Udine, Udine, Italy
| | - F Samassa
- Department of Medicine- Ophthalmology, University of Udine, Udine, Italy
| | - R Prosperi
- Department of Medicine- Ophthalmology, University of Udine, Udine, Italy
| | - F Barbieri
- Department of Paediatrics, Hospital of Pordenone, Pordenone, Italy
| | - R Dall'Amico
- Department of Paediatrics, Hospital of Pordenone, Pordenone, Italy
| | - P Cogo
- Department of Medicine- Paediatrics, University of Udine, Udine, Italy
| | - P Lanzetta
- Department of Medicine- Ophthalmology, University of Udine, Udine, Italy.
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5
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Samassa F, Ferrari ML, Husson J, Mikhailova A, Porat Z, Sidaner F, Brunner K, Teo TH, Frigimelica E, Tinevez JY, Sansonetti PJ, Thoulouze MI, Phalipon A. Shigella impairs human T lymphocyte responsiveness by hijacking actin cytoskeleton dynamics and T cell receptor vesicular trafficking. Cell Microbiol 2020; 22:e13166. [PMID: 31957253 PMCID: PMC7187243 DOI: 10.1111/cmi.13166] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 12/18/2019] [Accepted: 12/18/2019] [Indexed: 12/12/2022]
Abstract
Strategies employed by pathogenic enteric bacteria, such as Shigella, to subvert the host adaptive immunity are not well defined. Impairment of T lymphocyte chemotaxis by blockage of polarised edge formation has been reported upon Shigella infection. However, the functional impact of Shigella on T lymphocytes remains to be determined. Here, we show that Shigella modulates CD4+ T cell F‐actin dynamics and increases cell cortical stiffness. The scanning ability of T lymphocytes when encountering antigen‐presenting cells (APC) is subsequently impaired resulting in decreased cell–cell contacts (or conjugates) between the two cell types, as compared with non‐infected T cells. In addition, the few conjugates established between the invaded T cells and APCs display no polarised delivery and accumulation of the T cell receptor to the contact zone characterising canonical immunological synapses. This is most likely due to the targeting of intracellular vesicular trafficking by the bacterial type III secretion system (T3SS) effectors IpaJ and VirA. The collective impact of these cellular reshapings by Shigella eventually results in T cell activation dampening. Altogether, these results highlight the combined action of T3SS effectors leading to T cell defects upon Shigella infection.
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Affiliation(s)
- Fatoumata Samassa
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Mariana L Ferrari
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Julien Husson
- Laboratoire d'Hydrodynamique (LadHyX), Ecole polytechnique, CNRS, Institut Polytechnique de Paris, Palaiseau, France
| | | | - Ziv Porat
- Flow Cytometry Unit, Life Sciences Core Facility, Weizmann Institute of Sciences, Rehovot, Israel
| | | | - Katja Brunner
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Teck-Hui Teo
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | | | | | - Philippe J Sansonetti
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France.,Chaire de Microbiologie et Maladies Infectieuses, Collège de France, Paris, France
| | | | - Armelle Phalipon
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
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6
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Brunner K, Samassa F, Sansonetti PJ, Phalipon A. Shigella-mediated immunosuppression in the human gut: subversion extends from innate to adaptive immune responses. Hum Vaccin Immunother 2019; 15:1317-1325. [PMID: 30964713 PMCID: PMC6663138 DOI: 10.1080/21645515.2019.1594132] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 02/13/2019] [Accepted: 02/27/2019] [Indexed: 02/07/2023] Open
Abstract
The enteropathogen, Shigella, is highly virulent and remarkably adjusted to the intestinal environment of its almost exclusive human host. Key for Shigella pathogenicity is the injection of virulence effectors into the host cell via its type three secretion system (T3SS), initiating disease onset and progression by the vast diversity of the secreted T3SS effectors and their respective cellular targets. The multifaceted modulation of host signaling pathways exerted by Shigella T3SS effectors, which include the subversion of host innate immune defenses and the promotion of intracellular bacterial survival and dissemination, have been extensively reviewed in the recent past. This review focuses on the human species specificity of Shigella by discussing some possible evasion mechanisms towards the human, but not non-human or rodent gut innate defense barrier, leading to the lack of a relevant animal infection model. In addition, subversion mechanisms of the adaptive immune response are highlighted summarizing research advances of the recent years. In particular, the new paradigm of Shigella pathogenicity constituted of invasion-independent T3SS effector-mediated targeting of activated, human lymphocytes is discussed. Along with consequences on vaccine development, these findings offer new directions for future research endeavors towards a better understanding of immunity to Shigella infection.
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Affiliation(s)
- Katja Brunner
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
| | - Fatoumata Samassa
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
| | - Philippe J. Sansonetti
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
- Chaire de Microbiologie et Maladies Infectieuses, Collège de France, Paris, France
| | - Armelle Phalipon
- Molecular Microbial Pathogenesis Unit, Department of Cellular Biology of Infection, Institut Pasteur, Paris, France
- INSERM U1202, Paris, France
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Soudais C, Samassa F, Sarkis M, Le Bourhis L, Bessoles S, Blanot D, Hervé M, Schmidt F, Mengin-Lecreulx D, Lantz O. In Vitro and In Vivo Analysis of the Gram-Negative Bacteria-Derived Riboflavin Precursor Derivatives Activating Mouse MAIT Cells. J Immunol 2015; 194:4641-9. [PMID: 25870247 DOI: 10.4049/jimmunol.1403224] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 03/12/2015] [Indexed: 12/11/2022]
Abstract
Mucosal-associated invariant T (MAIT) cells recognize microbial compounds presented by the MHC-related 1 (MR1) protein. Although riboflavin precursor derivatives from Gram-positive bacteria have been characterized, some level of ligand heterogeneity has been suggested through the analysis of the MAIT cell TCR repertoire in humans and differential reactivity of human MAIT cell clones according to the bacteria. In this study, using Gram-negative bacteria mutated for the riboflavin biosynthetic pathway, we show a strict correlation between the ability to synthesize the 5-amino-ribityl-uracil riboflavin precursor and to activate polyclonal and quasi-monoclonal mouse MAIT cells. To our knowledge, we show for the first time that the semipurified bacterial fraction and the synthetic ligand activate murine MAIT cells in vitro and in vivo. We describe new MR1 ligands that do not activate MAIT cells but compete with bacterial and synthetic compounds activating MAIT cells, providing the capacity to modulate MAIT cell activation. Through competition experiments, we show that the most active synthetic MAIT cell ligand displays the same functional avidity for MR1 as does the microbial compound. Altogether, these results show that most, if not all, MAIT cell ligands found in Escherichia coli are related to the riboflavin biosynthetic pathway and display very limited heterogeneity.
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Affiliation(s)
| | | | - Manal Sarkis
- INSERM U932, Paris 75005, France; Département de Chimie, Institut Curie, Unité Mixte de Recherche 176, Paris 75005, France
| | | | | | - Didier Blanot
- Laboratoire des Enveloppes Bactériennes et Antibiotiques, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Unité Mixte de Recherche 8619, Centre National de la Recherche Scientifique, Université Paris-Sud, 91405 Orsay, France
| | - Mireille Hervé
- Laboratoire des Enveloppes Bactériennes et Antibiotiques, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Unité Mixte de Recherche 8619, Centre National de la Recherche Scientifique, Université Paris-Sud, 91405 Orsay, France
| | - Frédéric Schmidt
- Département de Chimie, Institut Curie, Unité Mixte de Recherche 176, Paris 75005, France
| | - Dominique Mengin-Lecreulx
- Laboratoire des Enveloppes Bactériennes et Antibiotiques, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Unité Mixte de Recherche 8619, Centre National de la Recherche Scientifique, Université Paris-Sud, 91405 Orsay, France
| | - Olivier Lantz
- INSERM U932, Paris 75005, France; Département de Biologie des Tumeurs, Institut Curie, Paris 75005, France; and Centre d'Investigation Clinique, CICBT507 IGR/Curie, Paris 75005, France
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