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Khorki ME, Shi T, Cianciolo EE, Burg AR, Chukwuma PC, Picarsic JL, Morrice MK, Woodle ES, Maltzman JS, Ferguson A, Katz JD, Baker BM, Hildeman DA. Prior viral infection primes cross-reactive CD8+ T cells that respond to mouse heart allografts. Front Immunol 2023; 14:1287546. [PMID: 38143762 PMCID: PMC10748599 DOI: 10.3389/fimmu.2023.1287546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 11/14/2023] [Indexed: 12/26/2023] Open
Abstract
Introduction Significant evidence suggests a connection between transplant rejection and the presence of high levels of pre-existing memory T cells. Viral infection can elicit viral-specific memory T cells that cross-react with allo-MHC capable of driving allograft rejection in mice. Despite these advances, and despite their critical role in transplant rejection, a systematic study of allo-reactive memory T cells, their specificities, and the role of cross-reactivity with viral antigens has not been performed. Methods Here, we established a model to identify, isolate, and characterize cross-reactive T cells using Nur77 reporter mice (C57BL/6 background), which transiently express GFP exclusively upon TCR engagement. We infected Nur77 mice with lymphocytic choriomeningitis virus (LCMV-Armstrong) to generate a robust memory compartment, where quiescent LCMV-specific memory CD8+ T cells could be readily tracked with MHC tetramer staining. Then, we transplanted LCMV immune mice with allogeneic hearts and monitored expression of GFP within MHC-tetramer defined viral-specific T cells as an indicator of their ability to cross-react with alloantigens. Results Strikingly, prior LCMV infection significantly increased the kinetics and magnitude of rejection as well as CD8+ T cell recruitment into allogeneic, but not syngeneic, transplanted hearts, relative to non-infected controls. Interestingly, as early as day 1 after allogeneic heart transplant an average of ~8% of MHC-tetramer+ CD8+ T cells expressed GFP, in contrast to syngeneic heart transplants, where the frequency of viral-specific CD8+ T cells that were GFP+ was <1%. These data show that a significant percentage of viral-specific memory CD8+ T cells expressed T cell receptors that also recognized alloantigens in vivo. Notably, the frequency of cross-reactive CD8+ T cells differed depending upon the viral epitope. Further, TCR sequences derived from cross-reactive T cells harbored distinctive motifs that may provide insight into cross-reactivity and allo-specificity. Discussion In sum, we have established a mouse model to track viral-specific, allo-specific, and cross-reactive T cells; revealing that prior infection elicits substantial numbers of viral-specific T cells that cross-react to alloantigen, respond very early after transplant, and may promote rapid rejection.
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Affiliation(s)
- M. Eyad Khorki
- Division of Nephrology & Hypertension, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
| | - Tiffany Shi
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Immunology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
- Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Eileen E. Cianciolo
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
| | - Ashley R. Burg
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
| | - P. Chukwunalu Chukwuma
- Department of Chemistry & Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN, United States
| | - Jennifer L. Picarsic
- Division of Pathology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Department of Pathology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Mary K. Morrice
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Immunology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - E. Steve Woodle
- Division of Transplantation, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Jonathan S. Maltzman
- Department of Medicine, Stanford University, Palo Alto, CA, United States
- Geriatric Research and Education Clinical Center, Veterans Affairs (VA) Palo Alto Health Care System, Palo Alto, CA, United States
| | - Autumn Ferguson
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
| | - Jonathan D. Katz
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Immunology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Brian M. Baker
- Department of Chemistry & Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN, United States
| | - David A. Hildeman
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Immunology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
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2
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Vianna P, Mendes MF, Bragatte MA, Ferreira PS, Salzano FM, Bonamino MH, Vieira GF. pMHC Structural Comparisons as a Pivotal Element to Detect and Validate T-Cell Targets for Vaccine Development and Immunotherapy-A New Methodological Proposal. Cells 2019; 8:cells8121488. [PMID: 31766602 PMCID: PMC6952977 DOI: 10.3390/cells8121488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/15/2019] [Accepted: 11/16/2019] [Indexed: 12/02/2022] Open
Abstract
The search for epitopes that will effectively trigger an immune response remains the “El Dorado” for immunologists. The development of promising immunotherapeutic approaches requires the appropriate targets to elicit a proper immune response. Considering the high degree of HLA/TCR diversity, as well as the heterogeneity of viral and tumor proteins, this number will invariably be higher than ideal to test. It is known that the recognition of a peptide-MHC (pMHC) by the T-cell receptor is performed entirely in a structural fashion, where the atomic interactions of both structures, pMHC and TCR, dictate the fate of the process. However, epitopes with a similar composition of amino acids can produce dissimilar surfaces. Conversely, sequences with no conspicuous similarities can exhibit similar TCR interaction surfaces. In the last decade, our group developed a database and in silico structural methods to extract molecular fingerprints that trigger T-cell immune responses, mainly referring to physicochemical similarities, which could explain the immunogenic differences presented by different pMHC-I complexes. Here, we propose an immunoinformatic approach that considers a structural level of information, combined with an experimental technology that simulates the presentation of epitopes for a T cell, to improve vaccine production and immunotherapy efficacy.
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Affiliation(s)
- Priscila Vianna
- Laboratory of Human Teratogenesis and Population Medical Genetics, Department of Genetics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre 91.501-970, Brazil;
| | - Marcus F.A. Mendes
- Laboratory of Bioinformatics (NBLI), Department of Genetics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre 91.501-970, Brazil (M.A.B.)
| | - Marcelo A. Bragatte
- Laboratory of Bioinformatics (NBLI), Department of Genetics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre 91.501-970, Brazil (M.A.B.)
| | - Priscila S. Ferreira
- Program of Immunology and Tumor Biology, Division of Experimental and Translational Research, Brazilian National Cancer Institute, Rio de Janeiro 20231-050, Brazil; (P.S.F.); (M.H.B.)
| | - Francisco M. Salzano
- Laboratory of Molecular Evolution, Department of Genetics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre 91.501-970, Brazil;
| | - Martin H. Bonamino
- Program of Immunology and Tumor Biology, Division of Experimental and Translational Research, Brazilian National Cancer Institute, Rio de Janeiro 20231-050, Brazil; (P.S.F.); (M.H.B.)
- Vice Presidency of Research and Biological Collections, Fundação Oswaldo Cruz, Rio de Janeiro 21040-900, Brazil
| | - Gustavo F. Vieira
- Laboratory of Bioinformatics (NBLI), Department of Genetics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre 91.501-970, Brazil (M.A.B.)
- Laboratory of Health Bioinformatics, Post Graduate Program in Health and Human Development, La Salle University, Canoas 91.501-970, Brazil
- Correspondence: ; Tel.: +55-51-3308-99-38; Fax: +55-51-3308-73-11
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Walsh DA, Borges da Silva H, Beura LK, Peng C, Hamilton SE, Masopust D, Jameson SC. The Functional Requirement for CD69 in Establishment of Resident Memory CD8 + T Cells Varies with Tissue Location. THE JOURNAL OF IMMUNOLOGY 2019; 203:946-955. [PMID: 31243092 DOI: 10.4049/jimmunol.1900052] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 06/10/2019] [Indexed: 12/21/2022]
Abstract
Recent studies have characterized populations of memory CD8+ T cells that do not recirculate through the blood but are, instead, retained in nonlymphoid tissues. Such CD8+ tissue resident memory T cells (TRM) are critical for pathogen control at barrier sites. Identifying TRM and defining the basis for their tissue residency is therefore of considerable importance for understanding protective immunity and improved vaccine design. Expression of the molecule CD69 is widely used as a definitive marker for TRM, yet it is unclear whether CD69 is universally required for producing or retaining TRM Using multiple mouse models of acute immunization, we found that the functional requirement for CD69 was highly variable, depending on the tissue examined, playing no detectable role in generation of TRM at some sites (such as the small intestine), whereas CD69 was critical for establishing resident cells in the kidney. Likewise, forced expression of CD69 (but not expression of a CD69 mutant unable to bind the egress factor S1PR1) promoted CD8+ TRM generation in the kidney but not in other tissues. Our findings indicate that the functional relevance of CD69 in generation and maintenance of CD8+ TRM varies considerably, chiefly dependent on the specific nonlymphoid tissue studied. Together with previous reports that suggest uncoupling of CD69 expression and tissue residency, these findings prompt caution in reliance on CD69 expression as a consistent marker of CD8+ TRM.
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Affiliation(s)
- Daniel A Walsh
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN 55455.,Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455; and
| | - Henrique Borges da Silva
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN 55455.,Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455; and
| | - Lalit K Beura
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN 55455.,Department of Microbiology and Immunology, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Changwei Peng
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN 55455.,Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455; and
| | - Sara E Hamilton
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN 55455.,Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455; and
| | - David Masopust
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN 55455.,Department of Microbiology and Immunology, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Stephen C Jameson
- Center for Immunology, University of Minnesota Medical School, Minneapolis, MN 55455; .,Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455; and
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4
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Successive crystal structure snapshots suggest the basis for MHC class I peptide loading and editing by tapasin. Proc Natl Acad Sci U S A 2019; 116:5055-5060. [PMID: 30808808 DOI: 10.1073/pnas.1807656116] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
MHC-I epitope presentation to CD8+ T cells is directly dependent on peptide loading and selection during antigen processing. However, the exact molecular bases underlying peptide selection and binding by MHC-I remain largely unknown. Within the peptide-loading complex, the peptide editor tapasin is key to the selection of MHC-I-bound peptides. Here, we have determined an ensemble of crystal structures of MHC-I in complex with the peptide exchange-associated dipeptide GL, as well as the tapasin-associated scoop loop, alone or in combination with candidate epitopes. These results combined with mutation analyses allow us to propose a molecular model underlying MHC-I peptide selection by tapasin. The N termini of bound peptides most probably bind first in the N-terminal and middle region of the MHC-I peptide binding cleft, upon which the peptide C termini are tested for their capacity to dislodge the tapasin scoop loop from the F pocket of the MHC-I cleft. Our results also indicate important differences in peptide selection between different MHC-I alleles.
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5
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Williams KL. The Biologics Revolution and Endotoxin Test Concerns. ENDOTOXIN DETECTION AND CONTROL IN PHARMA, LIMULUS, AND MAMMALIAN SYSTEMS 2019. [PMCID: PMC7123716 DOI: 10.1007/978-3-030-17148-3_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The advent of “at will” production of biologics in lieu of harvesting animal proteins (i.e. insulin) or human cadaver proteins (i.e. growth hormone) has revolutionized the treatment of disease. While the fruits of the biotechnology revolution are widely acknowledged, the realization of the differences in the means of production and changes in the manner of control of potential impurities and contaminants in regard to the new versus the old are less widely appreciated. This chapter is an overview of the biologics revolution in terms of the rigors of manufacturing required to produce them, their mechanism of action, and caveats of endotoxin control. It is a continulation of the previous chapter that established a basic background knowledge of adaptive immune principles necessary to understand the mode of action of both disease causation and biologics therapeutic treatment via immune modulation.
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6
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Hafstrand I, Doorduijn EM, Sun R, Talyzina A, Sluijter M, Pellegrino S, Sandalova T, Duru AD, van Hall T, Achour A. The Immunogenicity of a Proline-Substituted Altered Peptide Ligand toward the Cancer-Associated TEIPP Neoepitope Trh4 Is Unrelated to Complex Stability. THE JOURNAL OF IMMUNOLOGY 2018; 200:2860-2868. [PMID: 29507106 DOI: 10.4049/jimmunol.1700228] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 02/07/2018] [Indexed: 01/05/2023]
Abstract
Human cancers frequently display defects in Ag processing and presentation allowing for immune evasion, and they therefore constitute a significant challenge for T cell-based immunotherapy. We have previously demonstrated that the antigenicity of tumor-associated Ags can be significantly enhanced through unconventional residue modifications as a novel tool for MHC class I (MHC-I)-based immunotherapy approaches. We have also previously identified a novel category of cancer neo-epitopes, that is, T cell epitopes associated with impaired peptide processing (TEIPP), that are selectively presented by MHC-I on cells lacking the peptide transporter TAP. In this study, we demonstrate that substitution of the nonanchoring position 3 into a proline residue of the first identified TEIPP peptide, the murine Trh4, results in significantly enhanced recognition by antitumor CTLs toward the wild-type epitope. Although higher immunogenicity has in most cases been associated with increased MHC/peptide complex stability, our results demonstrate that the overall stability of H-2Db in complex with the highly immunogenic altered peptide ligand Trh4-p3P is significantly reduced compared with wild-type H-2Db/Trh4. Comparison of the crystal structures of the H-2Db/Trh4-p3P and H-2Db/Trh4 complexes revealed that the conformation of the nonconventional methionine anchor residue p5M is altered, deleting its capacity to form adequate sulfur-π interactions with H-2Db residues, thus reducing the overall longevity of the complex. Collectively, our results indicate that vaccination with Thr4-p3P significantly enhances T cell recognition of targets presenting the wild-type TEIPP epitope and that higher immunogenicity is not necessarily directly related to MHC/peptide complex stability, opening for the possibility to design novel peptide vaccines with reduced MHC/peptide complex stability.
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Affiliation(s)
- Ida Hafstrand
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, 17165 Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Solna, 17176 Stockholm, Sweden
| | - Elien M Doorduijn
- Medical Oncology, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Renhua Sun
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, 17165 Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Solna, 17176 Stockholm, Sweden
| | - Anna Talyzina
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, 17165 Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Solna, 17176 Stockholm, Sweden
| | - Marjolein Sluijter
- Medical Oncology, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Sara Pellegrino
- Department of Pharmaceutical Science, General and Organic Chemistry Section, University of Milan, 20133 Milan, Italy
| | - Tatyana Sandalova
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, 17165 Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Solna, 17176 Stockholm, Sweden
| | - Adil Doganay Duru
- Cell Therapy Institute, Nova Southeastern University, Fort Lauderdale, FL 33314; and.,College of Allopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL 33328
| | - Thorbald van Hall
- Medical Oncology, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands;
| | - Adnane Achour
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, 17165 Stockholm, Sweden; .,Department of Infectious Diseases, Karolinska University Hospital, Solna, 17176 Stockholm, Sweden
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7
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Hafstrand I, Badia-Martinez D, Josey BJ, Norström M, Buratto J, Pellegrino S, Duru AD, Sandalova T, Achour A. Crystal structures of H-2Db in complex with the LCMV-derived peptides GP92 and GP392 explain pleiotropic effects of glycosylation on antigen presentation and immunogenicity. PLoS One 2017; 12:e0189584. [PMID: 29253009 PMCID: PMC5734757 DOI: 10.1371/journal.pone.0189584] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 11/29/2017] [Indexed: 01/16/2023] Open
Abstract
Post-translational modifications significantly broaden the epitope repertoire for major histocompatibility class I complexes (MHC-I) and may allow viruses to escape immune recognition. Lymphocytic choriomeningitis virus (LCMV) infection of H-2b mice generates CD8+ CTL responses directed towards several MHC-I-restricted epitopes including the peptides GP92 (CSANNSHHYI) and GP392 (WLVTNGSYL), both with a N-glycosylation site. Interestingly, glycosylation has different effects on the immunogenicity and association capacity of these two epitopes to H-2Db. To assess the structural bases underlying these functional results, we determined the crystal structures of H-2Db in complex with GP92 (CSANNSHHYI) and GP392 (WLVTNGSYL) to 2.4 and 2.5 Å resolution, respectively. The structures reveal that while glycosylation of GP392 most probably impairs binding, the glycosylation of the asparagine residue in GP92, which protrudes towards the solvent, possibly allows for immune escape and/or forms a neo-epitope that may select for a different set of CD8 T cells. Altogether, the presented results provide a structural platform underlying the effects of post-translational modifications on epitope binding and/or immunogenicity, resulting in viral immune escape.
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Affiliation(s)
- Ida Hafstrand
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Department of Infectious Diseases, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Daniel Badia-Martinez
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Department of Infectious Diseases, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Benjamin John Josey
- NSU Cell Therapy Institute, Nova Southeastern University, Fort Lauderdale, FL, United State of America
- College of Allopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL, United State of America
| | - Melissa Norström
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Department of Infectious Diseases, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Jérémie Buratto
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Department of Infectious Diseases, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Sara Pellegrino
- DISFARM, Dipartimento di Scienze Farmaceutiche, Sezinone Chimica Generale e Organica, Università degli Studi, Milano, Italy
| | - Adil Doganay Duru
- NSU Cell Therapy Institute, Nova Southeastern University, Fort Lauderdale, FL, United State of America
- College of Allopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL, United State of America
| | - Tatyana Sandalova
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Department of Infectious Diseases, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Adnane Achour
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Department of Infectious Diseases, Karolinska University Hospital, Solna, Stockholm, Sweden
- * E-mail:
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8
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Basler M, Mundt S, Groettrup M. The immunoproteasome subunit LMP7 is required in the murine thymus for filling up a hole in the T cell repertoire. Eur J Immunol 2017; 48:419-429. [PMID: 29067678 DOI: 10.1002/eji.201747282] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/22/2017] [Accepted: 10/19/2017] [Indexed: 01/09/2023]
Abstract
Cells of hematopoietic origin express high levels of the immunoproteasome, a cytokine-inducible variant of the proteasome which has been implicated in regulating inflammatory responses and antigen presentation. In the thymus, medullary thymic epithelial cells (mTECs) and cortical thymic epithelial cells (cTECs) do express different proteasome subunits exerting chymotrypsin-like activities suggesting distinct functions in thymic T cell selection. Employing the lymphocytic choriomeningitis virus (LCMV) infection model, we could show that the immunoproteasome subunit LMP7 was absolutely required for the generation of LCMV GP118-125 -specific T cells although the class I mediated presentation of GP118-125 was not dependent on LMP7. Using bone marrow chimeras and adoptive transfer of LMP7-deficient CD8+ T cells into RAG1-deficient mice we show that LMP7-deficient mice lacked GP118-125 -specific T cell precursors and that LMP7 was required in radioresistant cells - most likely thymic epithelial cells - to enable their selection. Since LMP7 is strongly expressed in negatively selecting mTECs but barely in positively selecting cTECs our data suggest that LMP7 was required to avoid excessive negative selection of GP118-125 -specific T cell precursors. Taken together, this study demonstrates that the immunoproteasome is a crucial factor for filling up holes within the cytotoxic T cell repertoire.
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Affiliation(s)
- Michael Basler
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280, Kreuzlingen, Switzerland.,Division of Immunology, Department of Biology, University of Konstanz, D-78457, Konstanz, Germany
| | - Sarah Mundt
- Division of Immunology, Department of Biology, University of Konstanz, D-78457, Konstanz, Germany
| | - Marcus Groettrup
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280, Kreuzlingen, Switzerland.,Division of Immunology, Department of Biology, University of Konstanz, D-78457, Konstanz, Germany
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9
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Hafstrand I, Doorduijn EM, Duru AD, Buratto J, Oliveira CC, Sandalova T, van Hall T, Achour A. The MHC Class I Cancer-Associated Neoepitope Trh4 Linked with Impaired Peptide Processing Induces a Unique Noncanonical TCR Conformer. THE JOURNAL OF IMMUNOLOGY 2016; 196:2327-34. [PMID: 26800871 DOI: 10.4049/jimmunol.1502249] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 12/18/2015] [Indexed: 11/19/2022]
Abstract
MHC class I downregulation represents a significant challenge for successful T cell-based immunotherapy. T cell epitopes associated with impaired peptide processing (TEIPP) constitute a novel category of immunogenic Ags that are selectively presented on transporter associated with Ag processing-deficient cells. The TEIPP neoepitopes are CD8 T cell targets, derived from nonmutated self-proteins that might be exploited to prevent immune escape. In this study, the crystal structure of H-2D(b) in complex with the first identified TEIPP Ag (MCLRMTAVM) derived from the Trh4 protein has been determined to 2.25 Å resolution. In contrast to prototypic H-2D(b) peptides, Trh4 takes a noncanonical peptide-binding pattern with extensive sulfur-π interactions that contribute to the overall complex stability. Importantly, the noncanonical methionine at peptide position 5 acts as a main anchor, altering only the conformation of the H-2D(b) residues Y156 and H155 and thereby forming a unique MHC/peptide conformer that is essential for recognition by TEIPP-specific T cells. Substitution of peptide residues p2C and p5M to the conservative α-aminobutyric acid and norleucine, respectively, significantly reduced complex stability, without altering peptide conformation or T cell recognition. In contrast, substitution of p5M to a conventional asparagine abolished recognition by the H-2D(b)/Trh4-specific T cell clone LnB5. We anticipate that the H-2D(b)/Trh4 complex represents the first example, to our knowledge, of a broader repertoire of alternative MHC class I binders.
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Affiliation(s)
- Ida Hafstrand
- Science for Life Laboratory, Department of Medicine, Solna, Karolinska Institutet, SE-10450 Stockholm, Sweden; and
| | - Elien M Doorduijn
- Clinical Oncology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Adil Doganay Duru
- Science for Life Laboratory, Department of Medicine, Solna, Karolinska Institutet, SE-10450 Stockholm, Sweden; and
| | - Jeremie Buratto
- Science for Life Laboratory, Department of Medicine, Solna, Karolinska Institutet, SE-10450 Stockholm, Sweden; and
| | | | - Tatyana Sandalova
- Science for Life Laboratory, Department of Medicine, Solna, Karolinska Institutet, SE-10450 Stockholm, Sweden; and
| | - Thorbald van Hall
- Clinical Oncology, Leiden University Medical Center, Leiden 2333 ZA, the Netherlands
| | - Adnane Achour
- Science for Life Laboratory, Department of Medicine, Solna, Karolinska Institutet, SE-10450 Stockholm, Sweden; and
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10
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Motozono C, Pearson JA, De Leenheer E, Rizkallah PJ, Beck K, Trimby A, Sewell AK, Wong FS, Cole DK. Distortion of the Major Histocompatibility Complex Class I Binding Groove to Accommodate an Insulin-derived 10-Mer Peptide. J Biol Chem 2015; 290:18924-33. [PMID: 26085090 PMCID: PMC4521012 DOI: 10.1074/jbc.m114.622522] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 06/12/2015] [Indexed: 01/23/2023] Open
Abstract
The non-obese diabetic mouse model of type 1 diabetes continues to be an important tool for delineating the role of T-cell-mediated destruction of pancreatic β-cells. However, little is known about the molecular mechanisms that enable this disease pathway. We show that insulin reactivity by a CD8(+) T-cell clone, known to induce type 1 diabetes, is characterized by weak T-cell antigen receptor binding to a relatively unstable peptide-MHC. The structure of the native 9- and 10-mer insulin epitopes demonstrated that peptide residues 7 and 8 form a prominent solvent-exposed bulge that could potentially be the main focus of T-cell receptor binding. The C terminus of the peptide governed peptide-MHC stability. Unexpectedly, we further demonstrate a novel mode of flexible peptide presentation in which the MHC peptide-binding groove is able to "open the back door" to accommodate extra C-terminal peptide residues.
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Affiliation(s)
- Chihiro Motozono
- From the Division of Infection and Immunity and the Department of Immunology, Kinki University School of Medicine, Osaka 589-8511, Japan, and
| | - James A Pearson
- the Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Evy De Leenheer
- the Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | | | - Konrad Beck
- the Cardiff University School of Dentistry, Heath Park, Cardiff CF14 4XY, United Kingdom
| | | | | | - F Susan Wong
- the Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom,
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Improved structural method for T-cell cross-reactivity prediction. Mol Immunol 2015; 67:303-10. [PMID: 26141239 DOI: 10.1016/j.molimm.2015.06.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/03/2015] [Accepted: 06/16/2015] [Indexed: 10/23/2022]
Abstract
Cytotoxic T-lymphocytes (CTLs) are the key players of adaptive cellular immunity, being able to identify and eliminate infected cells through the interaction with peptide-loaded major histocompatibility complexes class I (pMHC-I). Despite the high specificity of this interaction, a given lymphocyte is actually able to recognize more than just one pMHC-I complex, a phenomenon referred as cross-reactivity. In the present work we describe the use of pMHC-I structural features as input for multivariate statistical methods, to perform standardized structure-based predictions of cross-reactivity among viral epitopes. Our improved approach was able to successfully identify cross-reactive targets among 28 naturally occurring hepatitis C virus (HCV) variants and among eight epitopes from the four dengue virus serotypes. In both cases, our results were supported by multiscale bootstrap resampling and by data from previously published in vitro experiments. The combined use of data from charges and accessible surface area (ASA) of selected residues over the pMHC-I surface provided a powerful way of assessing the structural features involved in triggering cross-reactive responses. Moreover, the use of an R package (pvclust) for assessing the uncertainty in the hierarchical cluster analysis provided a statistical support for the interpretation of results. Taken together, these methods can be applied to vaccine design, both for the selection of candidates capable of inducing immunity against different targets, or to identify epitopes that could trigger undesired immunological responses.
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12
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Cross-recognition of a myelin peptide by CD8+ T cells in the CNS is not sufficient to promote neuronal damage. J Neurosci 2015; 35:4837-50. [PMID: 25810515 DOI: 10.1523/jneurosci.3380-14.2015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Multiple sclerosis (MS) is an inflammatory disease of the CNS thought to be driven by CNS-specific T lymphocytes. Although CD8(+) T cells are frequently found in multiple sclerosis lesions, their distinct role remains controversial because direct signs of cytotoxicity have not been confirmed in vivo. In the present work, we determined that murine ovalbumin-transgenic (OT-1) CD8(+) T cells recognize the myelin peptide myelin oligodendrocyte glycoprotein 40-54 (MOG40-54) both in vitro and in vivo. The aim of this study was to investigate whether such cross-recognizing CD8(+) T cells are capable of inducing CNS damage in vivo. Using intravital two-photon microscopy in the mouse model of multiple sclerosis, we detected antigen recognition motility of the OT-1 CD8(+) T cells within the CNS leading to a selective enrichment in inflammatory lesions. However, this cross-reactivity of OT-1 CD8(+) T cells with MOG peptide in the CNS did not result in clinically or subclinically significant damage, which is different from myelin-specific CD4(+) Th17-mediated autoimmune pathology. Therefore, intravital imaging demonstrates that local myelin recognition by autoreactive CD8(+) T cells in inflammatory CNS lesions alone is not sufficient to induce disability or increase axonal injury.
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13
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Sinigaglia M, Antunes DA, Rigo MM, Chies JAB, Vieira GF. CrossTope: a curate repository of 3D structures of immunogenic peptide: MHC complexes. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2013; 2013:bat002. [PMID: 23396301 PMCID: PMC3567486 DOI: 10.1093/database/bat002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The CrossTope is a highly curate repository of three-dimensional structures of peptide:major histocompatibility complex (MHC) class I complexes (pMHC-I). The complexes hosted by this databank were obtained in protein databases and by large-scale in silico construction of pMHC-I structures, using a new approach developed by our group. At this moment, the database contains 182 ‘non-redundant’ pMHC-I complexes from two human and two murine alleles. A web server provides interface for database query. The user can download (i) structure coordinate files and (ii) topological and charges distribution maps images from the T-cell receptor-interacting surface of pMHC-I complexes. The retrieved structures and maps can be used to cluster similar epitopes in cross-reactivity approaches, to analyse viral escape mutations in a structural level or even to improve the immunogenicity of tumour antigens. Database URL: http://www.crosstope.com.br
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Affiliation(s)
- Marialva Sinigaglia
- NBLI - Núcleo de Bioinformática do Laboratório de Imunogenética, Department of Genetics, Universidade Federal do Rio Grande do Sul, 9500 Bento Gonçalves Avenue, Bldg 43323, Rm 225, 91501-970 Porto Alegre, RS, Brazil
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14
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Allerbring EB, Duru AD, Uchtenhagen H, Madhurantakam C, Tomek MB, Grimm S, Mazumdar PA, Friemann R, Uhlin M, Sandalova T, Nygren PÅ, Achour A. Unexpected T-cell recognition of an altered peptide ligand is driven by reversed thermodynamics. Eur J Immunol 2012; 42:2990-3000. [PMID: 22837158 DOI: 10.1002/eji.201242588] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 06/18/2012] [Accepted: 07/23/2012] [Indexed: 11/07/2022]
Abstract
The molecular basis underlying T-cell recognition of MHC molecules presenting altered peptide ligands is still not well-established. A hierarchy of T-cell activation by MHC class I-restricted altered peptide ligands has been defined using the T-cell receptor P14 specific for H-2D(b) in complex with the immunodominant lymphocytic choriomeningitis virus peptide gp33 (KAVYNFATM). While substitution of tyrosine to phenylalanine (Y4F) or serine (Y4S) abolished recognition by P14, the TCR unexpectedly recognized H-2D(b) in complex with the alanine-substituted semiagonist Y4A, which displayed the most significant structural modification. The observed functional hierarchy gp33 > Y4A > Y4S = Y4F was neither due to higher stabilization capacity nor to differences in structural conformation. However, thermodynamic analysis demonstrated that while recognition of the full agonist H-2D(b) /gp33 was strictly enthalpy driven, recognition of the weak agonist H-2D(b) /Y4A was instead entropy driven with a large reduction in the favorable enthalpy term. The fourfold larger negative heat capacity derived for the interaction of P14 with H-2D(b) /gp33 compared with H-2D(b) /Y4A can possibly be explained by higher water entrapment at the TCR/MHC interface, which is also consistent with the measured opposite entropy contributions for the interactions of P14 with both MHCs. In conclusion, this study demonstrates that P14 makes use of different strategies to adapt to structural modifications in the MHC/peptide complex.
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Affiliation(s)
- Eva B Allerbring
- Center for Infectious Medicine, Department of Medicine, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden
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15
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Madhurantakam C, Duru AD, Sandalova T, Webb JR, Achour A. Inflammation-associated nitrotyrosination affects TCR recognition through reduced stability and alteration of the molecular surface of the MHC complex. PLoS One 2012; 7:e32805. [PMID: 22431983 PMCID: PMC3303804 DOI: 10.1371/journal.pone.0032805] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Accepted: 02/03/2012] [Indexed: 01/07/2023] Open
Abstract
Nitrotyrosination of proteins, a hallmark of inflammation, may result in the production of MHC-restricted neoantigens that can be recognized by T cells and bypass the constraints of immunological self-tolerance. Here we biochemically and structurally assessed how nitrotyrosination of the lymphocytic choriomeningitis virus (LCMV)-associated immunodominant MHC class I-restricted epitopes gp33 and gp34 alters T cell recognition in the context of both H-2Db and H-2Kb. Comparative analysis of the crystal structures of H-2Kb/gp34 and H-2Kb/NY-gp34 demonstrated that nitrotyrosination of p3Y in gp34 abrogates a hydrogen bond interaction formed with the H-2Kb residue E152. As a consequence the conformation of the TCR-interacting E152 was profoundly altered in H-2Kb/NY-gp34 when compared to H-2Kb/gp34, thereby modifying the surface of the nitrotyrosinated MHC complex. Furthermore, nitrotyrosination of gp34 resulted in structural over-packing, straining the overall conformation and considerably reducing the stability of the H-2Kb/NY-gp34 MHC complex when compared to H-2Kb/gp34. Our structural analysis also indicates that nitrotyrosination of the main TCR-interacting residue p4Y in gp33 abrogates recognition of H-2Db/gp33-NY complexes by H-2Db/gp33-specific T cells through sterical hindrance. In conclusion, this study provides the first structural and biochemical evidence for how MHC class I-restricted nitrotyrosinated neoantigens may enable viral escape and break immune tolerance.
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Affiliation(s)
- Chaithanya Madhurantakam
- Centre for Infectious Medicine, Department of Medicine Huddinge, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Adil D. Duru
- Centre for Infectious Medicine, Department of Medicine Huddinge, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Tatyana Sandalova
- Centre for Infectious Medicine, Department of Medicine Huddinge, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - John R. Webb
- Trev and Joyce Deeley Research Centre, British Columbia Cancer Agency, Victoria, British Columbia, Canada
| | - Adnane Achour
- Centre for Infectious Medicine, Department of Medicine Huddinge, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
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16
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Immune system derived from homeostatic proliferation generates normal CD8 T-cell memory but altered repertoires and diminished heterologous immune responses. Blood 2008; 112:680-9. [PMID: 18509089 DOI: 10.1182/blood-2008-01-132464] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The host responds to lymphopenic environments by acute homeostatic proliferation of T lymphocytes, which acquire phenotypes similar to memory cells. Using T-cell knockout (KO) mice adoptively reconstituted with splenocytes from immunologically naive mice, we examined the immune responses of an immune system derived from homeostatically proliferating (HP) T cells. HP cells mounted relatively normal acute CD8 T-cell responses to lymphocytic choriomeningitis virus (LCMV), but with altered T-cell receptor (TCR) repertoires, and they became functional memory cells capable of recall responses. Although homeostatic proliferation does not normally fully restore T-cell numbers, the CD8(+) T-cell pool was completely restored in T-cell KO mice after LCMV infection. CD4 T-cell responses were lower and not fully restored but seemed sufficient to allow for complete differentiation of CD8 memory T cells. The LCMV-immune HP mouse had an immune repertoire heavily biased with LCMV epitope-specific T cells with oligoclonal expansions. LCMV-immune HP mice had reduced cross-reactive and non-cross-reactive CD8 T-cell responses when challenged with a T cell-cross-reactive virus. Thus, whereas an HP immune system is capable of mounting relatively normal acute and memory CD8 T-cell responses, the narrowing of the T-cell repertoire may reduce immune responses to subsequently encountered pathogens.
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Peixoto A, Evaristo C, Munitic I, Monteiro M, Charbit A, Rocha B, Veiga-Fernandes H. CD8 single-cell gene coexpression reveals three different effector types present at distinct phases of the immune response. ACTA ACUST UNITED AC 2007; 204:1193-205. [PMID: 17485515 PMCID: PMC2118592 DOI: 10.1084/jem.20062349] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
To study in vivo CD8 T cell differentiation, we quantified the coexpression of multiple genes in single cells throughout immune responses. After in vitro activation, CD8 T cells rapidly express effector molecules and cease their expression when the antigen is removed. Gene behavior after in vivo activation, in contrast, was quite heterogeneous. Different mRNAs were induced at very different time points of the response, were transcribed during different time periods, and could decline or persist independently of the antigen load. Consequently, distinct gene coexpression patterns/different cell types were generated at the various phases of the immune responses. During primary stimulation, inflammatory molecules were induced and down-regulated shortly after activation, generating early cells that only mediated inflammation. Cytotoxic T cells were generated at the peak of the primary response, when individual cells simultaneously expressed multiple killer molecules, whereas memory cells lost killer capacity because they no longer coexpressed killer genes. Surprisingly, during secondary responses gene transcription became permanent. Secondary cells recovered after antigen elimination were more efficient killers than cytotoxic T cells present at the peak of the primary response. Thus, primary responses produced two transient effector types. However, after boosting, CD8 T cells differentiate into long-lived killer cells that persist in vivo in the absence of antigen.
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Affiliation(s)
- António Peixoto
- Institut National de la Santé et de la Recherche Médicale, U591, 2U570, Université Paris Descartes, Medical Faculty René Descartes, Paris, France
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Rosloniec EF, Ivey RA, Whittington KB, Kang AH, Park HW. Crystallographic Structure of a Rheumatoid Arthritis MHC Susceptibility Allele, HLA-DR1 (DRB1*0101), Complexed with the Immunodominant Determinant of Human Type II Collagen. THE JOURNAL OF IMMUNOLOGY 2006; 177:3884-92. [PMID: 16951351 DOI: 10.4049/jimmunol.177.6.3884] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The expression of HLA-DR1 (DRB1*0101) is associated with an enhanced risk for developing rheumatoid arthritis (RA). To study its function, we have solved the three-dimensional structure of HLA-DR1 complexed with a candidate RA autoantigen, the human type II collagen peptide CII (259-273). Based on these structural data, the CII peptide is anchored by Phe263 at the P1 position and Glu266 at P4. Surprisingly, the Lys at the P2 position appears to play a dual role by participating in peptide binding via interactions with DRB1-His81 and Asn82, and TCR interaction, based on functional assays. The CII peptide is also anchored by the P4 Glu266 residue through an ionic interaction with DRB1-Arg71 and Glu28. Participation of DRB1-Arg71 is significant because it is part of the shared epitope expressed by DR alleles associated with RA susceptibility. Potential anchor residues at P6 and P9 of the CII peptide are both Gly, and the lack of side chains at these positions appears to result in both a narrower binding groove with the peptide protruding out of the groove at this end of the DR1 molecule. From the TCR perspective, the P2-Lys264, P5-Arg267, and P8-Lys270 residues are all oriented away from the binding groove and collectively represent a positive charged interface for CII-specific TCR binding. Comparison of the DR1-CII structure to a DR1-hemagglutinin peptide structure revealed that the binding of these two peptides generates significantly different interfaces for the interaction with their respective Ag-specific TCRs.
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Basler M, Moebius J, Elenich L, Groettrup M, Monaco JJ. An Altered T Cell Repertoire in MECL-1-Deficient Mice. THE JOURNAL OF IMMUNOLOGY 2006; 176:6665-72. [PMID: 16709825 DOI: 10.4049/jimmunol.176.11.6665] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Immunoproteasome subunits low-molecular mass polypeptide (LMP)2 and LMP7 affect Ag presentation by MHC class I molecules. In the present study, we investigated the function of the third immunosubunit LMP10/multicatalytic endopeptidase complex-like (MECL)-1 (beta2i) in MECL-1 gene-targeted mice. The number of CD8+ splenocytes in MECL-1-/- mice was 20% lower than in wild-type mice. Infection with lymphocytic choriomeningitis virus (LCMV) elicited a markedly reduced cytotoxic T cell (CTL) response to the LCMV epitopes GP276-286/Db and NP205-212/Kb in MECL-1-/- mice. The weak CTL response to GP276-286/Db was not due to an impaired generation of this epitope but was attributed to a decreased precursor frequency of GP276-286/Db-specific T cells. The expansion of TCR-Vbeta10+ T cells, which contain GP276-286/Db-specific cells, was reduced in LCMV-infected MECL-1-/- mice. Taken together, our data reveal an in vivo function of MECL-1 in codetermining the T cell repertoire for an antiviral CTL response.
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Affiliation(s)
- Michael Basler
- Division of Immunology, Department of Biology, University of Constance, Konstanz, Germany
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