1
|
Sun Y, Pumroy RA, Mallik L, Chaudhuri A, Wang C, Hwang D, Danon JN, Dasteh Goli K, Moiseenkova-Bell VY, Sgourakis NG. CryoEM structure of an MHC-I/TAPBPR peptide-bound intermediate reveals the mechanism of antigen proofreading. Proc Natl Acad Sci U S A 2025; 122:e2416992122. [PMID: 39786927 PMCID: PMC11745410 DOI: 10.1073/pnas.2416992122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2024] [Accepted: 12/05/2024] [Indexed: 01/30/2025] Open
Abstract
Class I major histocompatibility complex (MHC-I) proteins play a pivotal role in adaptive immunity by displaying epitopic peptides to CD8+ T cells. The chaperones tapasin and TAPBPR promote the selection of immunogenic antigens from a large pool of intracellular peptides. Interactions of chaperoned MHC-I molecules with incoming peptides are transient in nature, and as a result, the precise antigen proofreading mechanism remains elusive. Here, we leverage a high-fidelity TAPBPR variant and conformationally stabilized MHC-I, to determine the solution structure of the human antigen editing complex bound to a peptide decoy by cryogenic electron microscopy (cryo-EM) at an average resolution of 3.0 Å. Antigen proofreading is mediated by transient interactions formed between the nascent peptide binding groove with the P2/P3 peptide anchors, where conserved MHC-I residues stabilize incoming peptides through backbone-focused contacts. Finally, using our high-fidelity chaperone, we demonstrate robust peptide exchange on the cell surface across multiple clinically relevant human MHC-I allomorphs. Our work has important ramifications for understanding the selection of immunogenic epitopes for T cell screening and vaccine design applications.
Collapse
Affiliation(s)
- Yi Sun
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA19104
- Center for Computational and Genomic Medicine and Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA19104
| | - Ruth A. Pumroy
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Leena Mallik
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA19104
- Center for Computational and Genomic Medicine and Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA19104
| | - Apala Chaudhuri
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA19104
- Center for Computational and Genomic Medicine and Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA19104
| | - Chloe Wang
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
- Immunology Graduate Program, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA19104
| | - Daniel Hwang
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA19104
- Center for Computational and Genomic Medicine and Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA19104
| | - Julia N. Danon
- Center for Computational and Genomic Medicine and Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA19104
| | - Kimia Dasteh Goli
- Center for Computational and Genomic Medicine and Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA19104
| | - Vera Y. Moiseenkova-Bell
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA19104
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Nikolaos G. Sgourakis
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA19104
- Center for Computational and Genomic Medicine and Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA19104
| |
Collapse
|
2
|
Ghoreyshi ZS, Teimouri H, Kolomeisky AB, George JT. Integration of kinetic data into affinity-based models for improved T cell specificity prediction. Biophys J 2024; 123:4115-4122. [PMID: 39520055 PMCID: PMC11628827 DOI: 10.1016/j.bpj.2024.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 09/15/2024] [Accepted: 11/04/2024] [Indexed: 11/16/2024] Open
Abstract
T cell receptor (TCR) and peptide-major histocompatibility complex (pMHC) interactions that result in T cell activation are complex and have been distinguished by their equilibrium affinity and kinetic profiles. While prior affinity-based models can successfully predict meaningful TCR-pMHC interactions in many cases, they occasionally fail at identifying TCR-pMHC interactions with low binding affinity. This study analyzes TCR-pMHC systems for which empirical kinetic and affinity data exist and prior affinity-based predictions have failed. We identify criteria for TCR-pMHC systems with available kinetic information where the introduction of a correction factor improves energy-based model predictions. This kinetic correction factor offers a means to refine existing models with additional data and offers molecular insights to help reconcile previously conflicting reports concerning the influence of TCR-pMHC binding kinetics and affinity on T cell activation.
Collapse
Affiliation(s)
- Zahra S Ghoreyshi
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas; Center for Theoretical Biological Physics, Rice University, Houston, Texas
| | - Hamid Teimouri
- Center for Theoretical Biological Physics, Rice University, Houston, Texas; Department of Chemistry, Rice University, Houston, Texas
| | - Anatoly B Kolomeisky
- Center for Theoretical Biological Physics, Rice University, Houston, Texas; Department of Chemistry, Rice University, Houston, Texas; Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas.
| | - Jason T George
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas; Center for Theoretical Biological Physics, Rice University, Houston, Texas.
| |
Collapse
|
3
|
Sun Y, Pumroy RA, Mallik L, Chaudhuri A, Wang C, Hwang D, Danon JN, Goli KD, Moiseenkova-Bell V, Sgourakis NG. CryoEM structure of an MHC-I/TAPBPR peptide bound intermediate reveals the mechanism of antigen proofreading. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.05.606663. [PMID: 39211162 PMCID: PMC11361172 DOI: 10.1101/2024.08.05.606663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Class I major histocompatibility complex (MHC-I) proteins play a pivotal role in adaptive immunity by displaying epitopic peptides to CD8+ T cells. The chaperones tapasin and TAPBPR promote the selection of immunogenic antigens from a large pool of intracellular peptides. Interactions of chaperoned MHC-I molecules with incoming peptides are transient in nature, and as a result, the precise antigen proofreading mechanism remains elusive. Here, we leverage a high-fidelity TAPBPR variant and conformationally stabilized MHC-I, to determine the solution structure of the human antigen editing complex bound to a peptide decoy by cryogenic electron microscopy (cryo-EM) at an average resolution of 3.0 Å. Antigen proofreading is mediated by transient interactions formed between the nascent peptide binding groove with the P2/P3 peptide anchors, where conserved MHC-I residues stabilize incoming peptides through backbone-focused contacts. Finally, using our high-fidelity chaperone, we demonstrate robust peptide exchange on the cell surface across multiple clinically relevant human MHC-I allomorphs. Our work has important ramifications for understanding the selection of immunogenic epitopes for T cell screening and vaccine design applications.
Collapse
|
4
|
Hernández González JE, de Araujo AS. Alchemical Calculation of Relative Free Energies for Charge-Changing Mutations at Protein-Protein Interfaces Considering Fixed and Variable Protonation States. J Chem Inf Model 2023; 63:6807-6822. [PMID: 37851531 DOI: 10.1021/acs.jcim.3c00972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
The calculation of relative free energies (ΔΔG) for charge-changing mutations at protein-protein interfaces through alchemical methods remains challenging due to variations in the system's net charge during charging steps, the possibility of mutated and contacting ionizable residues occurring in various protonation states, and undersampling issues. In this study, we present a set of strategies, collectively termed TIRST/TIRST-H+, to address some of these challenges. Our approaches combine thermodynamic integration (TI) with the prediction of pKa shifts to calculate ΔΔG values. Moreover, special sets of restraints are employed to keep the alchemically transformed molecules separated. The accuracy of the devised approaches was assessed on a large and diverse data set comprising 164 point mutations of charged residues (Asp, Glu, Lys, and Arg) to Ala at the protein-protein interfaces of complexes with known three-dimensional structures. Mean absolute and root-mean-square errors ranging from 1.38 to 1.66 and 1.89 to 2.44 kcal/mol, respectively, and Pearson correlation coefficients of ∼0.6 were obtained when testing the approaches on the selected data set using the GPU-TI module of Amber18 suite and the ff14SB force field. Furthermore, the inclusion of variable protonation states for the mutated acid residues improved the accuracy of the predicted ΔΔG values. Therefore, our results validate the use of TIRST/TIRST-H+ in prospective studies aimed at evaluating the impact of charge-changing mutations to Ala on the stability of protein-protein complexes.
Collapse
|
5
|
van de Sandt CE, Nguyen THO, Gherardin NA, Crawford JC, Samir J, Minervina AA, Pogorelyy MV, Rizzetto S, Szeto C, Kaur J, Ranson N, Sonda S, Harper A, Redmond SJ, McQuilten HA, Menon T, Sant S, Jia X, Pedrina K, Karapanagiotidis T, Cain N, Nicholson S, Chen Z, Lim R, Clemens EB, Eltahla A, La Gruta NL, Crowe J, Lappas M, Rossjohn J, Godfrey DI, Thomas PG, Gras S, Flanagan KL, Luciani F, Kedzierska K. Newborn and child-like molecular signatures in older adults stem from TCR shifts across human lifespan. Nat Immunol 2023; 24:1890-1907. [PMID: 37749325 PMCID: PMC10602853 DOI: 10.1038/s41590-023-01633-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 08/24/2023] [Indexed: 09/27/2023]
Abstract
CD8+ T cells provide robust antiviral immunity, but how epitope-specific T cells evolve across the human lifespan is unclear. Here we defined CD8+ T cell immunity directed at the prominent influenza epitope HLA-A*02:01-M158-66 (A2/M158) across four age groups at phenotypic, transcriptomic, clonal and functional levels. We identify a linear differentiation trajectory from newborns to children then adults, followed by divergence and a clonal reset in older adults. Gene profiles in older adults closely resemble those of newborns and children, despite being clonally distinct. Only child-derived and adult-derived A2/M158+CD8+ T cells had the potential to differentiate into highly cytotoxic epitope-specific CD8+ T cells, which was linked to highly functional public T cell receptor (TCR)αβ signatures. Suboptimal TCRαβ signatures in older adults led to less proliferation, polyfunctionality, avidity and recognition of peptide mutants, although displayed no signs of exhaustion. These data suggest that priming T cells at different stages of life might greatly affect CD8+ T cell responses toward viral infections.
Collapse
Affiliation(s)
- Carolien E van de Sandt
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Thi H O Nguyen
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Nicholas A Gherardin
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | | | - Jerome Samir
- School of Medical Sciences and The Kirby Institute, UNSW Sydney, Sydney, New South Wales, Australia
| | | | - Mikhail V Pogorelyy
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Simone Rizzetto
- School of Medical Sciences and The Kirby Institute, UNSW Sydney, Sydney, New South Wales, Australia
| | - Christopher Szeto
- Viral and Structural Immunology Laboratory, Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia
- Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Jasveen Kaur
- School of Health Sciences and School of Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Nicole Ranson
- School of Health Sciences and School of Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Sabrina Sonda
- School of Health Sciences and School of Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Alice Harper
- School of Health Sciences and School of Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Samuel J Redmond
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Hayley A McQuilten
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Tejas Menon
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Sneha Sant
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Xiaoxiao Jia
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Kate Pedrina
- Victorian Infectious Diseases Reference Laboratory, The Royal Melbourne Hospital at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Theo Karapanagiotidis
- Victorian Infectious Diseases Reference Laboratory, The Royal Melbourne Hospital at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Natalie Cain
- Victorian Infectious Diseases Reference Laboratory, The Royal Melbourne Hospital at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Suellen Nicholson
- Victorian Infectious Diseases Reference Laboratory, The Royal Melbourne Hospital at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Zhenjun Chen
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Ratana Lim
- Obstetrics, Nutrition and Endocrinology Group, Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - E Bridie Clemens
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Auda Eltahla
- School of Medical Sciences and The Kirby Institute, UNSW Sydney, Sydney, New South Wales, Australia
| | - Nicole L La Gruta
- Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Jane Crowe
- Deepdene Surgery, Deepdene, Victoria, Australia
| | - Martha Lappas
- Obstetrics, Nutrition and Endocrinology Group, Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - Jamie Rossjohn
- Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - Dale I Godfrey
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Paul G Thomas
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Stephanie Gras
- Viral and Structural Immunology Laboratory, Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia
- Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Katie L Flanagan
- School of Health Sciences and School of Medicine, University of Tasmania, Launceston, Tasmania, Australia
- School of Health and Biomedical Science, RMIT University, Melbourne, Victoria, Australia
- Tasmanian Vaccine Trial Centre, Clifford Craig Foundation, Launceston General Hospital, Launceston, Tasmania, Australia
| | - Fabio Luciani
- School of Medical Sciences and The Kirby Institute, UNSW Sydney, Sydney, New South Wales, Australia
| | - Katherine Kedzierska
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia.
| |
Collapse
|
6
|
Ciacchi L, van de Garde MDB, Ladell K, Farenc C, Poelen MCM, Miners KL, Llerena C, Reid HH, Petersen J, Price DA, Rossjohn J, van Els CACM. CD4 + T cell-mediated recognition of a conserved cholesterol-dependent cytolysin epitope generates broad antibacterial immunity. Immunity 2023; 56:1082-1097.e6. [PMID: 37100059 DOI: 10.1016/j.immuni.2023.03.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 12/31/2022] [Accepted: 03/30/2023] [Indexed: 04/28/2023]
Abstract
CD4+ T cell-mediated immunity against Streptococcus pneumoniae (pneumococcus) can protect against recurrent bacterial colonization and invasive pneumococcal diseases (IPDs). Although such immune responses are common, the pertinent antigens have remained elusive. We identified an immunodominant CD4+ T cell epitope derived from pneumolysin (Ply), a member of the bacterial cholesterol-dependent cytolysins (CDCs). This epitope was broadly immunogenic as a consequence of presentation by the pervasive human leukocyte antigen (HLA) allotypes DPB1∗02 and DPB1∗04 and recognition via architecturally diverse T cell receptors (TCRs). Moreover, the immunogenicity of Ply427-444 was underpinned by core residues in the conserved undecapeptide region (ECTGLAWEWWR), enabling cross-recognition of heterologous bacterial pathogens expressing CDCs. Molecular studies further showed that HLA-DP4-Ply427-441 was engaged similarly by private and public TCRs. Collectively, these findings reveal the mechanistic determinants of near-global immune focusing on a trans-phyla bacterial epitope, which could inform ancillary strategies to combat various life-threatening infectious diseases, including IPDs.
Collapse
Affiliation(s)
- Lisa Ciacchi
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Martijn D B van de Garde
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, Utrecht 3721MA, the Netherlands
| | - Kristin Ladell
- Division of Infection and Immunity, Cardiff University School of Medicine, University Hospital of Wales, Cardiff CF14 4XN, UK
| | - Carine Farenc
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Martien C M Poelen
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, Utrecht 3721MA, the Netherlands
| | - Kelly L Miners
- Division of Infection and Immunity, Cardiff University School of Medicine, University Hospital of Wales, Cardiff CF14 4XN, UK
| | - Carmen Llerena
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Hugh H Reid
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Jan Petersen
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - David A Price
- Division of Infection and Immunity, Cardiff University School of Medicine, University Hospital of Wales, Cardiff CF14 4XN, UK; Systems Immunity Research Institute, Cardiff University School of Medicine, University Hospital of Wales, Cardiff CF14 4XN, UK.
| | - Jamie Rossjohn
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Division of Infection and Immunity, Cardiff University School of Medicine, University Hospital of Wales, Cardiff CF14 4XN, UK; Systems Immunity Research Institute, Cardiff University School of Medicine, University Hospital of Wales, Cardiff CF14 4XN, UK.
| | - Cécile A C M van Els
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, Utrecht 3721MA, the Netherlands; Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht 3584CL, the Netherlands.
| |
Collapse
|
7
|
Morita D, Asa M, Sugita M. Engagement with the TCR induces plasticity in antigenic ligands bound to MHC class I and CD1 molecules. Int Immunol 2023; 35:7-17. [PMID: 36053252 DOI: 10.1093/intimm/dxac046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 08/31/2022] [Indexed: 01/25/2023] Open
Abstract
Complementarity-determining regions (CDRs) of αβ T-cell receptors (TCRs) sense peptide-bound MHC (pMHC) complexes via chemical interactions, thereby mediating antigen specificity and MHC restriction. Flexible finger-like movement of CDR loops contributes to the establishment of optimal interactions with pMHCs. In contrast, peptide ligands captured in MHC molecules are considered more static because of the rigid hydrogen-bond network that stabilizes peptide ligands in the antigen-binding groove of MHC molecules. An array of crystal structures delineating pMHC complexes in TCR-docked and TCR-undocked forms is now available, which enables us to assess TCR engagement-induced conformational changes in peptide ligands. In this short review, we overview conformational changes in MHC class I-bound peptide ligands upon TCR docking, followed by those for CD1-bound glycolipid ligands. Finally, we analyze the co-crystal structure of the TCR:lipopeptide-bound MHC class I complex that we recently reported. We argue that TCR engagement-induced conformational changes markedly occur in lipopeptide ligands, which are essential for exposure of a primary T-cell epitope to TCRs. These conformational changes are affected by amino acid residues, such as glycine, that do not interact directly with TCRs. Thus, ligand recognition by specific TCRs involves not only T-cell epitopes but also non-epitopic amino acid residues. In light of their critical function, we propose to refer to these residues as non-epitopic residues affecting ligand plasticity and antigenicity (NR-PA).
Collapse
Affiliation(s)
- Daisuke Morita
- Laboratory of Cell Regulation, Institute for Life and Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.,Laboratory of Cell Regulation and Molecular Network, Graduate School of Biostudies, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Minori Asa
- Laboratory of Cell Regulation, Institute for Life and Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.,Laboratory of Cell Regulation and Molecular Network, Graduate School of Biostudies, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masahiko Sugita
- Laboratory of Cell Regulation, Institute for Life and Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.,Laboratory of Cell Regulation and Molecular Network, Graduate School of Biostudies, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| |
Collapse
|
8
|
Nguyen AT, Lau HMP, Sloane H, Jayasinghe D, Mifsud NA, Chatzileontiadou DSM, Grant EJ, Szeto C, Gras S. Homologous peptides derived from influenza A, B and C viruses induce variable CD8 + T cell responses with cross-reactive potential. Clin Transl Immunology 2022; 11:e1422. [PMID: 36275878 PMCID: PMC9581725 DOI: 10.1002/cti2.1422] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 09/17/2022] [Accepted: 09/21/2022] [Indexed: 11/06/2022] Open
Abstract
Objective Influenza A, B and C viruses (IAV, IBV and ICV, respectively) circulate globally, infecting humans and causing widespread morbidity and mortality. Here, we investigate the T cell response towards an immunodominant IAV epitope, NP265‐273, and its IBV and ICV homologues, presented by HLA‐A*03:01 molecule expressed in ~ 4% of the global population (~ 300 million people). Methods We assessed the magnitude (tetramer staining) and quality of the CD8+ T cell response (intracellular cytokine staining) towards NP265‐IAV and described the T cell receptor (TCR) repertoire used to recognise this immunodominant epitope. We next assessed the immunogenicity of NP265‐IAV homologue peptides from IBV and ICV and the ability of CD8+ T cells to cross‐react towards these homologous peptides. Furthermore, we determined the structures of NP265‐IAV and NP323‐IBV peptides in complex with HLA‐A*03:01 by X‐ray crystallography. Results Our study provides a detailed characterisation of the CD8+ T cell response towards NP265‐IAV and its IBV and ICV homologues. The data revealed a diverse repertoire for NP265‐IAV that is associated with superior anti‐viral protection. Evidence of cross‐reactivity between the three different influenza virus strain‐derived epitopes was observed, indicating the discovery of a potential vaccination target that is broad enough to cover all three influenza strains. Conclusion We show that while there is a potential to cross‐protect against distinct influenza virus lineages, the T cell response was stronger against the IAV peptide than IBV or ICV, which is an important consideration when choosing targets for future vaccine design.
Collapse
Affiliation(s)
- Andrea T Nguyen
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia,Department of Biochemistry and Chemistry, La Trobe Institute for Molecular ScienceLa Trobe UniversityBundooraVICAustralia
| | - Hiu Ming Peter Lau
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia
| | - Hannah Sloane
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia,Department of Biochemistry and Chemistry, La Trobe Institute for Molecular ScienceLa Trobe UniversityBundooraVICAustralia
| | - Dhilshan Jayasinghe
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia,Department of Biochemistry and Chemistry, La Trobe Institute for Molecular ScienceLa Trobe UniversityBundooraVICAustralia
| | - Nicole A Mifsud
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia
| | - Demetra SM Chatzileontiadou
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia,Department of Biochemistry and Chemistry, La Trobe Institute for Molecular ScienceLa Trobe UniversityBundooraVICAustralia
| | - Emma J Grant
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia,Department of Biochemistry and Chemistry, La Trobe Institute for Molecular ScienceLa Trobe UniversityBundooraVICAustralia
| | - Christopher Szeto
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia,Department of Biochemistry and Chemistry, La Trobe Institute for Molecular ScienceLa Trobe UniversityBundooraVICAustralia
| | - Stephanie Gras
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVICAustralia,Department of Biochemistry and Chemistry, La Trobe Institute for Molecular ScienceLa Trobe UniversityBundooraVICAustralia
| |
Collapse
|
9
|
Petrova GV, Naumov YN, Naumova EN, Gorski J. Role of cross-reactivity in cellular immune targeting of influenza A M1 58-66 variant peptide epitopes. Front Immunol 2022; 13:956103. [PMID: 36211433 PMCID: PMC9539824 DOI: 10.3389/fimmu.2022.956103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 09/02/2022] [Indexed: 11/30/2022] Open
Abstract
The immunologic significance of cross-reactivity of TCR recognition of peptide:MHC complexes is still poorly understood. We have described TCR cross-reactivity in a system involving polyclonal CD8 T cell recognition of the well characterized influenza viral M158-66 epitope. While M158-66 is generally conserved between influenza A isolates, error-prone transcription generates stable variant RNA during infection which could act as novel epitopes. If packaged and viable, variant genomic RNA generates an influenza quasispecies. The stable RNA variants would generate a new transmissible epitope that can select a specific repertoire, which itself should have cross-reactive properties. We tested two candidate peptides in which Thr65 is changed to Ala (A65) or Ser (S65) using recall responses to identify responding T cell clonotypes. Both peptides generated large polyclonal T cell repertoires of their own with repertoire characteristics and cross-reactivity patterns like that observed for the M158-66 repertoire. Both substitutions could be present in viral genomes or mRNA at sufficient frequency during an infection to drive immunity. Peptides from the resulting protein would be a target for CD8 cells irrespective of virus viability or transmissibility. These data support the hypothesis that cross-reactivity is important for immunity against RNA virus infections.
Collapse
Affiliation(s)
- Galina V. Petrova
- The Blood Research Institute, Versiti Wisconsin, Milwaukee, WI, United States
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
| | | | - Elena N. Naumova
- Division of Nutrition Epidemiology and Data Science, Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA, United States
| | - Jack Gorski
- The Blood Research Institute, Versiti Wisconsin, Milwaukee, WI, United States
| |
Collapse
|
10
|
HLA-A*11:01-restricted CD8+ T cell immunity against influenza A and influenza B viruses in Indigenous and non-Indigenous people. PLoS Pathog 2022; 18:e1010337. [PMID: 35255101 PMCID: PMC8929706 DOI: 10.1371/journal.ppat.1010337] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 03/17/2022] [Accepted: 02/03/2022] [Indexed: 11/19/2022] Open
Abstract
HLA-A*11:01 is one of the most prevalent human leukocyte antigens (HLAs), especially in East Asian and Oceanian populations. It is also highly expressed in Indigenous people who are at high risk of severe influenza disease. As CD8+ T cells can provide broadly cross-reactive immunity to distinct influenza strains and subtypes, including influenza A, B and C viruses, understanding CD8+ T cell immunity to influenza viruses across prominent HLA types is needed to rationally design a universal influenza vaccine and generate protective immunity especially for high-risk populations. As only a handful of HLA-A*11:01-restricted CD8+ T cell epitopes have been described for influenza A viruses (IAVs) and epitopes for influenza B viruses (IBVs) were still unknown, we embarked on an epitope discovery study to define a CD8+ T cell landscape for HLA-A*11:01-expressing Indigenous and non-Indigenous Australian people. Using mass-spectrometry, we identified IAV- and IBV-derived peptides presented by HLA-A*11:01 during infection. 79 IAV and 57 IBV peptides were subsequently screened for immunogenicity in vitro with peripheral blood mononuclear cells from HLA-A*11:01-expressing Indigenous and non-Indigenous Australian donors. CD8+ T cell immunogenicity screening revealed two immunogenic IAV epitopes (A11/PB2320-331 and A11/PB2323-331) and the first HLA-A*11:01-restricted IBV epitopes (A11/M41-49, A11/NS1186-195 and A11/NP511-520). The immunogenic IAV- and IBV-derived peptides were >90% conserved among their respective influenza viruses. Identification of novel immunogenic HLA-A*11:01-restricted CD8+ T cell epitopes has implications for understanding how CD8+ T cell immunity is generated towards IAVs and IBVs. These findings can inform the development of rationally designed, broadly cross-reactive influenza vaccines to ensure protection from severe influenza disease in HLA-A*11:01-expressing individuals. Influenza A and influenza B viral infections cause significant morbidity and mortality. Established CD8+ T cell immunity directed at conserved viral regions provides protection against influenza viruses, drives rapid recovery, and leads to less severe clinical outcomes. Killer CD8+ T cells recognising viral peptides presented by HLA class I glycoproteins can provide broad immunity across distinct influenza strains and subtypes. Using immunopeptidomics, we identified novel CD8+ T cell targets for influenza A and influenza B viruses in the context of HLA-A*11:01, an HLA-I allomorph highly prevalent in East Asia and Oceania, including Indigenous populations. Our study provides key insights for T cell-directed vaccines and immunotherapies.
Collapse
|
11
|
Nakayama M, Michels AW. Using the T Cell Receptor as a Biomarker in Type 1 Diabetes. Front Immunol 2021; 12:777788. [PMID: 34868047 PMCID: PMC8635517 DOI: 10.3389/fimmu.2021.777788] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 10/26/2021] [Indexed: 12/20/2022] Open
Abstract
T cell receptors (TCRs) are unique markers that define antigen specificity for a given T cell. With the evolution of sequencing and computational analysis technologies, TCRs are now prime candidates for the development of next-generation non-cell based T cell biomarkers, which provide a surrogate measure to assess the presence of antigen-specific T cells. Type 1 diabetes (T1D), the immune-mediated form of diabetes, is a prototypical organ specific autoimmune disease in which T cells play a pivotal role in targeting pancreatic insulin-producing beta cells. While the disease is now predictable by measuring autoantibodies in the peripheral blood directed to beta cell proteins, there is an urgent need to develop T cell markers that recapitulate T cell activity in the pancreas and can be a measure of disease activity. This review focuses on the potential and challenges of developing TCR biomarkers for T1D. We summarize current knowledge about TCR repertoires and clonotypes specific for T1D and discuss challenges that are unique for autoimmune diabetes. Ultimately, the integration of large TCR datasets produced from individuals with and without T1D along with computational 'big data' analysis will facilitate the development of TCRs as potentially powerful biomarkers in the development of T1D.
Collapse
MESH Headings
- Alleles
- Animals
- Biomarkers
- Diabetes Mellitus, Type 1/diagnosis
- Diabetes Mellitus, Type 1/etiology
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 1/therapy
- Disease Susceptibility
- Epitopes/chemistry
- Epitopes/immunology
- Epitopes/metabolism
- Genetic Predisposition to Disease
- Genetic Variation
- Histocompatibility Antigens/genetics
- Histocompatibility Antigens/immunology
- Humans
- Islets of Langerhans/immunology
- Islets of Langerhans/metabolism
- Peptides/immunology
- Peptides/metabolism
- Protein Binding
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/metabolism
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
Collapse
Affiliation(s)
- Maki Nakayama
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
| | - Aaron W. Michels
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
| |
Collapse
|
12
|
Ehrlich R, Kamga L, Gil A, Luzuriaga K, Selin LK, Ghersi D. SwarmTCR: a computational approach to predict the specificity of T cell receptors. BMC Bioinformatics 2021; 22:422. [PMID: 34493215 PMCID: PMC8422754 DOI: 10.1186/s12859-021-04335-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 08/16/2021] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND With more T cell receptor sequence data becoming available, the need for bioinformatics approaches to predict T cell receptor specificity is even more pressing. Here we present SwarmTCR, a method that uses labeled sequence data to predict the specificity of T cell receptors using a nearest-neighbor approach. SwarmTCR works by optimizing the weights of the individual CDR regions to maximize classification performance. RESULTS We compared the performance of SwarmTCR against another nearest-neighbor method and showed that SwarmTCR performs well both with bulk sequencing data and with single cell data. In addition, we show that the weights returned by SwarmTCR are biologically interpretable. CONCLUSIONS Computationally predicting the specificity of T cell receptors can be a powerful tool to shed light on the immune response against infectious diseases and cancers, autoimmunity, cancer immunotherapy, and immunopathology. SwarmTCR is distributed freely under the terms of the GPL-3 license. The source code and all sequencing data are available at GitHub ( https://github.com/thecodingdoc/SwarmTCR ).
Collapse
Affiliation(s)
- Ryan Ehrlich
- School of Interdisciplinary Informatics, College of Information Science and Technology, University of Nebraska at Omaha, 1110 S 67TH, Omaha, NE, 68182, USA
| | - Larisa Kamga
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Anna Gil
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Katherine Luzuriaga
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Liisa K Selin
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Dario Ghersi
- School of Interdisciplinary Informatics, College of Information Science and Technology, University of Nebraska at Omaha, 1110 S 67TH, Omaha, NE, 68182, USA.
| |
Collapse
|
13
|
Zhang W, Hawkins PG, He J, Gupta NT, Liu J, Choonoo G, Jeong SW, Chen CR, Dhanik A, Dillon M, Deering R, Macdonald LE, Thurston G, Atwal GS. A framework for highly multiplexed dextramer mapping and prediction of T cell receptor sequences to antigen specificity. SCIENCE ADVANCES 2021; 7:7/20/eabf5835. [PMID: 33990328 PMCID: PMC8121425 DOI: 10.1126/sciadv.abf5835] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 03/25/2021] [Indexed: 05/04/2023]
Abstract
T cell receptor (TCR) antigen-specific recognition is essential for the adaptive immune system. However, building a TCR-antigen interaction map has been challenging due to the staggering diversity of TCRs and antigens. Accordingly, highly multiplexed dextramer-TCR binding assays have been recently developed, but the utility of the ensuing large datasets is limited by the lack of robust computational methods for normalization and interpretation. Here, we present a computational framework comprising a novel method, ICON (Integrative COntext-specific Normalization), for identifying reliable TCR-pMHC (peptide-major histocompatibility complex) interactions and a neural network-based classifier TCRAI that outperforms other state-of-the-art methods for TCR-antigen specificity prediction. We further demonstrated that by combining ICON and TCRAI, we are able to discover novel subgroups of TCRs that bind to a given pMHC via different mechanisms. Our framework facilitates the identification and understanding of TCR-antigen-specific interactions for basic immunological research and clinical immune monitoring.
Collapse
Affiliation(s)
- Wen Zhang
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA.
| | - Peter G Hawkins
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Jing He
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Namita T Gupta
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Jinrui Liu
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Gabrielle Choonoo
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Se W Jeong
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Calvin R Chen
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Ankur Dhanik
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Myles Dillon
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Raquel Deering
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Lynn E Macdonald
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Gavin Thurston
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA
| | - Gurinder S Atwal
- Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY 10591, USA.
| |
Collapse
|
14
|
Zhu Y, Huang C, Su M, Ge Z, Gao L, Shi Y, Wang X, Chen J. Characterization of amino acid residues of T-cell receptors interacting with HLA-A*02-restricted antigen peptides. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:495. [PMID: 33850892 PMCID: PMC8039679 DOI: 10.21037/atm-21-835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background The present study aimed to explore residues’ properties interacting with HLA-A*02-restricted peptides on T-cell receptors (TCRs) and their effects on bond types of interaction and binding free energy. Methods We searched the crystal structures of HLA-A*02-restricted peptide-TCR complexes from the Protein Data Bank (PDB) database and subsequently collected relevant parameters. We then employed Schrodinger to analyze the bond types of interaction and Gromacs 2019 to evaluate the TCR-antigen peptide complex’s molecular dynamics simulation. Finally, we compared the changes of bond types of interaction and binding free energy before and after residue substitution to ensure consistency of the conditions before and after residue substitution. Results The main sites on the antigen peptides that formed the intermolecular interaction [hydrogen bond (HB) and pi stack] with TCRs were P4, P8, P2, and P6. The hydrophobicity of the amino acids inside or outside the disulfide bond of TCRs may be related to the intermolecular interaction and binding free energy between TCRs and peptides. Residues located outside the disulfide bond of TCR α or β chains and forming pi stack force played favorable roles in the complex intermolecular interaction and binding free energy. The residues of the TCR α or β chains that interacted with peptides were replaced by alanine (Ala) or glycine (Gly), and their intermolecular binding free energy of the complex had been improved. However, it had nothing to do with the formation of HB. Conclusions The findings of this study suggest that the hydrophobic nature of the amino acids inside or outside the disulfide bonds on the TCR may be associated with the intermolecular interaction and binding between the TCR and polypeptide. The residues located outside the TCR α or β single-chain disulfide bond and forming the pi-stack force showed a beneficial effect on the intermolecular interaction and binding of the complex. In addition, the part of the residues on the TCR α or β single chain that produced bond types of interaction with the polypeptide after being replaced by Ala or Gly, the intermolecular binding free energy of the complex was increased, regardless of whether HB was formed.
Collapse
Affiliation(s)
- Ying Zhu
- Department of Oncology, First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Changxin Huang
- Department of Oncology, Affiliated Hospital of Hangzhou Normal University, Hangzhou, China
| | - Meng Su
- Master Class, Zhejiang Chinese Medical University, Fourth School of Clinical Medicine, Hangzhou, China
| | - Zuanmin Ge
- Master Class, Hangzhou Normal University, School of Medicine, Hangzhou, China
| | - Lanlan Gao
- Master Class, Hangzhou Normal University, School of Medicine, Hangzhou, China
| | - Yanfei Shi
- Master Class, Hangzhou Normal University, School of Medicine, Hangzhou, China
| | - Xuechun Wang
- Master Class, Zhejiang Chinese Medical University, Fourth School of Clinical Medicine, Hangzhou, China
| | - Jianfeng Chen
- Department of Proctology, Affiliated Hospital of Hangzhou Normal University, Hangzhou, China
| |
Collapse
|
15
|
The αβTCR mechanosensor exploits dynamic ectodomain allostery to optimize its ligand recognition site. Proc Natl Acad Sci U S A 2020; 117:21336-21345. [PMID: 32796106 DOI: 10.1073/pnas.2005899117] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Each [Formula: see text]T cell receptor (TCR) functions as a mechanosensor. The TCR is comprised of a clonotypic TCR[Formula: see text] ligand-binding heterodimer and the noncovalently associated CD3 signaling subunits. When bound by ligand, an antigenic peptide arrayed by a major histocompatibility complex molecule (pMHC), the TCR[Formula: see text] has a longer bond lifetime under piconewton-level loads. The atomistic mechanism of this "catch bond" behavior is unknown. Here, we perform molecular dynamics simulation of a TCR[Formula: see text]-pMHC complex and its variants under physiologic loads to identify this mechanism and any attendant TCR[Formula: see text] domain allostery. The TCR[Formula: see text]-pMHC interface is dynamically maintained by contacts with a spectrum of occupancies, introducing a level of control via relative motion between Vα and Vβ variable domains containing the pMHC-binding complementarity-determining region (CDR) loops. Without adequate load, the interfacial contacts are unstable, whereas applying sufficient load suppresses Vα-Vβ motion, stabilizing the interface. A second level of control is exerted by Cα and Cβ constant domains, especially Cβ and its protruding FG-loop, that create mismatching interfaces among the four TCR[Formula: see text] domains and with a pMHC ligand. Applied load enhances fit through deformation of the TCR[Formula: see text] molecule. Thus, the catch bond involves the entire TCR[Formula: see text] conformation, interdomain motion, and interfacial contact dynamics, collectively. This multilayered architecture of the machinery fosters fine-tuning of cellular response to load and pMHC recognition. Since the germline-derived TCR[Formula: see text] ectodomain is structurally conserved, the proposed mechanism can be universally adopted to operate under load during immune surveillance by diverse [Formula: see text]TCRs constituting the T cell repertoire.
Collapse
|
16
|
Yarmarkovich M, Warrington JM, Farrel A, Maris JM. Identification of SARS-CoV-2 Vaccine Epitopes Predicted to Induce Long-Term Population-Scale Immunity. Cell Rep Med 2020; 1:100036. [PMID: 32835302 PMCID: PMC7276303 DOI: 10.1016/j.xcrm.2020.100036] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 04/29/2020] [Accepted: 05/27/2020] [Indexed: 12/11/2022]
Abstract
Here we propose a SARS-CoV-2 vaccine design concept based on identification of highly conserved regions of the viral genome and newly acquired adaptations, both predicted to generate epitopes presented on major histocompatibility complex (MHC) class I and II across the vast majority of the population. We further prioritize genomic regions that generate highly dissimilar peptides from the human proteome and are also predicted to produce B cell epitopes. We propose sixty-five 33-mer peptide sequences, a subset of which can be tested using DNA or mRNA delivery strategies. These include peptides that are contained within evolutionarily divergent regions of the spike protein reported to increase infectivity through increased binding to the ACE2 receptor and within a newly evolved furin cleavage site thought to increase membrane fusion. Validation and implementation of this vaccine concept could specifically target specific vulnerabilities of SARS-CoV-2 and should engage a robust adaptive immune response in the vast majority of the population.
Collapse
Affiliation(s)
- Mark Yarmarkovich
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - John M. Warrington
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Alvin Farrel
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Department of Biomedical and Health Informatics, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - John M. Maris
- Division of Oncology and Center for Childhood Cancer Research, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
17
|
Yarmarkovich M, Warrington JM, Farrel A, Maris JM. A SARS-CoV-2 Vaccination Strategy Focused on Population-Scale Immunity. SSRN 2020:3575161. [PMID: 32714112 PMCID: PMC7366814 DOI: 10.2139/ssrn.3575161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/05/2020] [Indexed: 11/15/2022]
Abstract
Here we propose a vaccination strategy for SARS-CoV-2 based on identification of both highly conserved regions of the virus and newly acquired adaptations that are presented by MHC class I and II across the vast majority of the population, are highly dissimilar from the human proteome, and are predicted B cell epitopes. We present 65 peptide sequences that we expect to result in a safe and effective vaccine which can be rapidly tested in DNA, mRNA, or synthetic peptide constructs. These include epitopes that are contained within evolutionarily divergent regions of the spike protein reported to increase infectivity through increased binding to the ACE2 receptor, and within a novel furin cleavage site thought to increase membrane fusion. This vaccination strategy specifically targets unique vulnerabilities of SARS-CoV-2 and should engage a robust adaptive immune response in the vast majority of the human population.
Collapse
Affiliation(s)
- Mark Yarmarkovich
- Division of Oncology and Center for Childhood Cancer Research; Children’s Hospital of Philadelphia; Philadelphia, PA, 19104; USA
| | - John M. Warrington
- Division of Oncology and Center for Childhood Cancer Research; Children’s Hospital of Philadelphia; Philadelphia, PA, 19104; USA
| | - Alvin Farrel
- Department of Biomedical and Health Informatics, Children’s Hospital of Philadelphia; Philadelphia, PA, 19104
| | - John M. Maris
- Division of Oncology and Center for Childhood Cancer Research; Children’s Hospital of Philadelphia; Philadelphia, PA, 19104; USA
- Perelman School of Medicine at the University of Pennsylvania; Philadelphia, PA, 19104
| |
Collapse
|
18
|
Yarmarkovich M, Warrington JM, Farrel A, Maris JM. A SARS-CoV-2 Vaccination Strategy Focused on Population-Scale Immunity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.03.31.018978. [PMID: 32511347 PMCID: PMC7255782 DOI: 10.1101/2020.03.31.018978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Here we propose a vaccination strategy for SARS-CoV-2 based on identification of both highly conserved regions of the virus and newly acquired adaptations that are presented by MHC class I and II across the vast majority of the population, are highly dissimilar from the human proteome, and are predicted B cell epitopes. We present 65 peptide sequences that we expect to result in a safe and effective vaccine which can be rapidly tested in DNA, mRNA, or synthetic peptide constructs. These include epitopes that are contained within evolutionarily divergent regions of the spike protein reported to increase infectivity through increased binding to the ACE2 receptor, and within a novel furin cleavage site thought to increase membrane fusion. This vaccination strategy specifically targets unique vulnerabilities of SARS-CoV-2 and should engage a robust adaptive immune response in the vast majority of the human population.
Collapse
|
19
|
Gil A, Kamga L, Chirravuri-Venkata R, Aslan N, Clark F, Ghersi D, Luzuriaga K, Selin LK. Epstein-Barr Virus Epitope-Major Histocompatibility Complex Interaction Combined with Convergent Recombination Drives Selection of Diverse T Cell Receptor α and β Repertoires. mBio 2020; 11:e00250-20. [PMID: 32184241 PMCID: PMC7078470 DOI: 10.1128/mbio.00250-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 02/11/2020] [Indexed: 01/07/2023] Open
Abstract
Recognition modes of individual T cell receptors (TCRs) are well studied, but factors driving the selection of TCR repertoires from primary through persistent human virus infections are less well understood. Using deep sequencing, we demonstrate a high degree of diversity of Epstein-Barr virus (EBV)-specific clonotypes in acute infectious mononucleosis (AIM). Only 9% of unique clonotypes detected in AIM persisted into convalescence; the majority (91%) of unique clonotypes detected in AIM were not detected in convalescence and were seeming replaced by equally diverse "de novo" clonotypes. The persistent clonotypes had a greater probability of being generated than nonpersistent clonotypes due to convergence recombination of multiple nucleotide sequences to encode the same amino acid sequence, as well as the use of shorter complementarity-determining regions 3 (CDR3s) with fewer nucleotide additions (i.e., sequences closer to germ line). Moreover, the two most immunodominant HLA-A2-restricted EBV epitopes, BRLF1109 and BMLF1280, show highly distinct antigen-specific public (i.e., shared between individuals) features. In fact, TCRα CDR3 motifs played a dominant role, while TCRβ played a minimal role, in the selection of TCR repertoire to an immunodominant EBV epitope, BRLF1. This contrasts with the majority of previously reported repertoires, which appear to be selected either on TCRβ CDR3 interactions with peptide/major histocompatibility complex (MHC) or in combination with TCRα CDR3. Understanding of how TCR-peptide-MHC complex interactions drive repertoire selection can be used to develop optimal strategies for vaccine design or generation of appropriate adoptive immunotherapies for viral infections in transplant settings or for cancer.IMPORTANCE Several lines of evidence suggest that TCRα and TCRβ repertoires play a role in disease outcomes and treatment strategies during viral infections in transplant patients and in cancer and autoimmune disease therapy. Our data suggest that it is essential that we understand the basic principles of how to drive optimum repertoires for both TCR chains, α and β. We address this important issue by characterizing the CD8 TCR repertoire to a common persistent human viral infection (EBV), which is controlled by appropriate CD8 T cell responses. The ultimate goal would be to determine if the individuals who are infected asymptomatically develop a different TCR repertoire than those that develop the immunopathology of AIM. Here, we begin by doing an in-depth characterization of both CD8 T cell TCRα and TCRβ repertoires to two immunodominant EBV epitopes over the course of AIM, identifying potential factors that may be driving their selection.
Collapse
Affiliation(s)
- Anna Gil
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Larisa Kamga
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | | | - Nuray Aslan
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Fransenio Clark
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Dario Ghersi
- School of Interdisciplinary Informatics, University of Nebraska at Omaha, Omaha, Nebraska, USA
| | - Katherine Luzuriaga
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Liisa K Selin
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| |
Collapse
|
20
|
Tripathi SK, Salunke DM. Exploring the different states of wild-type T-cell receptor and mutant conformational changes towards understanding the antigen recognition. J Biomol Struct Dyn 2020; 39:188-201. [PMID: 31870204 DOI: 10.1080/07391102.2019.1708795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Recognition of proteolytic peptide fragments presented by major histocompatibility complex (MHC) on target cells by T-cell receptor (TCR) is among the most important interactions in the adaptive immune system. Several computational studies have been performed to investigate conformational and dynamical properties of TCRs for enhanced immunogenicity. Here, we present the large-scale molecular dynamics (MD) simulation studies of the two comprehensive systems consisting of the wild-type and mutant IG4 TCR in complex with the tumor epitope NY-ESO peptide (SLLMWITQC) and analyzed for mapping conformational changes of TCR in the states prior to antigen binding, upon antigen binding and after the antigen was released. All of the simulations were performed with different states of TCRs for each 1000 ns of simulation time, providing six simulations for time duration of 6000 ns (6µs). We show that rather than undergoing most critical conformational changes upon antigen binding, the high proportion of complementarity-determining region (CDR) loops change by comparatively small amount. The hypervariable CDRα3 and CDRβ3 loops showed significant structural changes. Interestingly, the TCR β chain loops showed the least changes, which is reliable with recent implications that β domain of TCR may propel antigen interaction. The mutant shows higher rigidity than wild-type even in released state; expose an induced fit mechanism occurring from the re-structuring of CDRα3 loop and can allow enhanced binding affinity of the peptide antigen. Additionally, we show that CDRα3 loop and peptide contacts are an adaptive feature of affinity enhanced mutant TCR.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Sunil Kumar Tripathi
- Structural Immunology Group, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India
| | - Dinakar M Salunke
- Structural Immunology Group, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India.,Structural Immunology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| |
Collapse
|
21
|
Kamga L, Gil A, Song I, Brody R, Ghersi D, Aslan N, Stern LJ, Selin LK, Luzuriaga K. CDR3α drives selection of the immunodominant Epstein Barr virus (EBV) BRLF1-specific CD8 T cell receptor repertoire in primary infection. PLoS Pathog 2019; 15:e1008122. [PMID: 31765434 PMCID: PMC6901265 DOI: 10.1371/journal.ppat.1008122] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 12/09/2019] [Accepted: 10/03/2019] [Indexed: 12/20/2022] Open
Abstract
The T cell receptor (TCR) repertoire is an essential component of the CD8 T-cell immune response. Here, we seek to investigate factors that drive selection of TCR repertoires specific to the HLA-A2-restricted immunodominant epitope BRLF1109-117 (YVLDHLIVV) over the course of primary Epstein Barr virus (EBV) infection. Using single-cell paired TCRαβ sequencing of tetramer sorted CD8 T cells ex vivo, we show at the clonal level that recognition of the HLA-A2-restricted BRLF1 (YVL-BR, BRLF-1109) epitope is mainly driven by the TCRα chain. For the first time, we identify a CDR3α (complementarity determining region 3 α) motif, KDTDKL, resulting from an obligate AV8.1-AJ34 pairing that was shared by all four individuals studied. This observation coupled with the fact that this public AV8.1-KDTDKL-AJ34 TCR pairs with multiple different TCRβ chains within the same donor (median 4; range: 1–9), suggests that there are some unique structural features of the interaction between the YVL-BR/MHC and the AV8.1-KDTDKL-AJ34 TCR that leads to this high level of selection. Newly developed TCR motif algorithms identified a lysine at position 1 of the CDR3α motif that is highly conserved and likely important for antigen recognition. Crystal structure analysis of the YVL-BR/HLA-A2 complex revealed that the MHC-bound peptide bulges at position 4, exposing a negatively charged aspartic acid that may interact with the positively charged lysine of CDR3α. TCR cloning and site-directed mutagenesis of the CDR3α lysine ablated YVL-BR-tetramer staining and substantially reduced CD69 upregulation on TCR mutant-transduced cells following antigen-specific stimulation. Reduced activation of T cells expressing this CDR3 motif was also observed following exposure to mutated (D4A) peptide. In summary, we show that a highly public TCR repertoire to an immunodominant epitope of a common human virus is almost completely selected on the basis of CDR3α and provide a likely structural basis for the selection. These studies emphasize the importance of examining TCRα, as well as TCRβ, in understanding the CD8 T cell receptor repertoire. EBV is a ubiquitous human virus that has been linked to several diseases, including cancers and post-transplant lymphoproliferative disorders. CD8 T cells are important for controlling EBV replication. Generation and maintenance of virus-specific CD8 T cells is dependent on specific interaction between MHC-peptide complexes on the infected cell and the TCR. In this study, we performed single cell sequencing of paired TCR α and β chains from EBV-specific CD8 T cells isolated at two time points (primary infection and convalescence) from four individuals undergoing acute EBV infection. We describe a TCRα sequence that was shared by all four individuals and identify conserved residues within this sequence that likely contribute to viral recognition. Examination of the crystal structure of the peptide-MHC complex and subsequent experimental data suggest that a specific interaction between a negatively charged aspartic acid at position 4 of the peptide and a positively charged lysine in the TCR may be particularly important. These findings are highly relevant to current efforts to understand how the TCR repertoire may contribute to or protect against disease, the development of TCR diagnostics for diseases, and at improving the efficacy of T cell based therapies.
Collapse
MESH Headings
- Amino Acid Sequence
- CD8-Positive T-Lymphocytes/immunology
- Complementarity Determining Regions/genetics
- Complementarity Determining Regions/immunology
- Complementarity Determining Regions/metabolism
- Epitopes, T-Lymphocyte/immunology
- Epstein-Barr Virus Infections/immunology
- Epstein-Barr Virus Infections/virology
- HLA-A2 Antigen/immunology
- Herpesvirus 4, Human/immunology
- Humans
- Immediate-Early Proteins/genetics
- Immediate-Early Proteins/immunology
- Immediate-Early Proteins/metabolism
- Immunodominant Epitopes/immunology
- Peptide Fragments/immunology
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- T-Lymphocytes, Cytotoxic/immunology
- Trans-Activators/genetics
- Trans-Activators/immunology
- Trans-Activators/metabolism
Collapse
Affiliation(s)
- Larisa Kamga
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Anna Gil
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Inyoung Song
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Robin Brody
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Dario Ghersi
- School of Interdisciplinary Informatics, University of Nebraska at Omaha, Nebraska, United States of America
| | - Nuray Aslan
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Lawrence J. Stern
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Liisa K. Selin
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- * E-mail: (LKS); (KL)
| | - Katherine Luzuriaga
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- * E-mail: (LKS); (KL)
| |
Collapse
|
22
|
Crooks JE, Boughter CT, Scott LR, Adams EJ. The Hypervariable Loops of Free TCRs Sample Multiple Distinct Metastable Conformations in Solution. Front Mol Biosci 2018; 5:95. [PMID: 30483515 PMCID: PMC6243104 DOI: 10.3389/fmolb.2018.00095] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 10/22/2018] [Indexed: 01/12/2023] Open
Abstract
CD4+ and CD8+ αβ T cell antigen recognition is determined by the interaction between the TCR Complementarity Determining Region (CDR) loops and the peptide-presenting MHC complex. These T cells are known for their ability to recognize multiple pMHC complexes, and for a necessary promiscuity that is required for their selection and function in the periphery. Crystallographic studies have previously elucidated the role of structural interactions in TCR engagement, but our understanding of the dynamic process that occurs during TCR binding is limited. To better understand the dynamic states that exist for TCR CDR loops in solution, and how this relates to their states when in complex with pMHC, we simulated the 2C T cell receptor in solution using all-atom molecular dynamics in explicit water and constructed a Markov State Model for each of the CDR3α and CDR3β loops. These models reveal multiple metastable states for the CDR3 loops in solution. Simulation data and metastable states reproduce known CDR3β crystal conformations, and reveal several novel conformations suggesting that CDR3β bound states are the result of search processes from nearby pre-existing equilibrium conformational states. Similar simulations of the invariant, Type I Natural Killer T cell receptor NKT15, which engages the monomorphic, MHC-like CD1d ligand, demonstrate that iNKT TCRs also have distinct states, but comparatively restricted degrees of motion.
Collapse
Affiliation(s)
- James E Crooks
- Graduate Program in Biophysical Sciences, University of Chicago, Chicago, IL, United States
| | - Christopher T Boughter
- Graduate Program in Biophysical Sciences, University of Chicago, Chicago, IL, United States
| | - L Ridgway Scott
- Department of Computer Science, University of Chicago, Chicago, IL, United States
| | - Erin J Adams
- Committee on Immunology University of Chicago, Chicago, IL, United States
| |
Collapse
|
23
|
Rowntree LC, Nguyen THO, Halim H, Purcell AW, Rossjohn J, Gras S, Kotsimbos TC, Mifsud NA. Inability To Detect Cross-Reactive Memory T Cells Challenges the Frequency of Heterologous Immunity among Common Viruses. THE JOURNAL OF IMMUNOLOGY 2018; 200:3993-4003. [DOI: 10.4049/jimmunol.1800010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/17/2018] [Indexed: 01/08/2023]
|
24
|
Singh NK, Riley TP, Baker SCB, Borrman T, Weng Z, Baker BM. Emerging Concepts in TCR Specificity: Rationalizing and (Maybe) Predicting Outcomes. THE JOURNAL OF IMMUNOLOGY 2017; 199:2203-2213. [PMID: 28923982 DOI: 10.4049/jimmunol.1700744] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 07/10/2017] [Indexed: 12/14/2022]
Abstract
T cell specificity emerges from a myriad of processes, ranging from the biological pathways that control T cell signaling to the structural and physical mechanisms that influence how TCRs bind peptides and MHC proteins. Of these processes, the binding specificity of the TCR is a key component. However, TCR specificity is enigmatic: TCRs are at once specific but also cross-reactive. Although long appreciated, this duality continues to puzzle immunologists and has implications for the development of TCR-based therapeutics. In this review, we discuss TCR specificity, emphasizing results that have emerged from structural and physical studies of TCR binding. We show how the TCR specificity/cross-reactivity duality can be rationalized from structural and biophysical principles. There is excellent agreement between predictions from these principles and classic predictions about the scope of TCR cross-reactivity. We demonstrate how these same principles can also explain amino acid preferences in immunogenic epitopes and highlight opportunities for structural considerations in predictive immunology.
Collapse
Affiliation(s)
- Nishant K Singh
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556.,Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556; and
| | - Timothy P Riley
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556.,Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556; and
| | - Sarah Catherine B Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556.,Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556; and
| | - Tyler Borrman
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Brian M Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556; .,Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556; and
| |
Collapse
|
25
|
Yang X, Chen G, Weng NP, Mariuzza RA. Structural basis for clonal diversity of the human T-cell response to a dominant influenza virus epitope. J Biol Chem 2017; 292:18618-18627. [PMID: 28931605 DOI: 10.1074/jbc.m117.810382] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/08/2017] [Indexed: 12/20/2022] Open
Abstract
Influenza A virus (IAV) causes an acute infection in humans that is normally eliminated by CD8+ cytotoxic T lymphocytes. Individuals expressing the MHC class I molecule HLA-A2 produce cytotoxic T lymphocytes bearing T-cell receptors (TCRs) that recognize the immunodominant IAV epitope GILGFVFTL (GIL). Most GIL-specific TCRs utilize α/β chain pairs encoded by the TRAV27/TRBV19 gene combination to recognize this relatively featureless peptide epitope (canonical TCRs). However, ∼40% of GIL-specific TCRs express a wide variety of other TRAV/TRBV combinations (non-canonical TCRs). To investigate the structural underpinnings of this remarkable diversity, we determined the crystal structure of a non-canonical GIL-specific TCR (F50) expressing the TRAV13-1/TRBV27 gene combination bound to GIL-HLA-A2 to 1.7 Å resolution. Comparison of the F50-GIL-HLA-A2 complex with the previously published complex formed by a canonical TCR (JM22) revealed that F50 and JM22 engage GIL-HLA-A2 in markedly different orientations. These orientations are distinguished by crossing angles of TCR to peptide-MHC of 29° for F50 versus 69° for JM22 and by a focus by F50 on the C terminus rather than the center of the MHC α1 helix for JM22. In addition, F50, unlike JM22, uses a tryptophan instead of an arginine to fill a critical notch between GIL and the HLA-A2 α2 helix. The F50-GIL-HLA-A2 complex shows that there are multiple structurally distinct solutions to recognizing an identical peptide-MHC ligand with sufficient affinity to elicit a broad anti-IAV response that protects against viral escape and T-cell clonal loss.
Collapse
Affiliation(s)
- Xinbo Yang
- From the University of Maryland Institute for Bioscience and Biotechnology Research, W. M. Keck Laboratory for Structural Biology, Rockville, Maryland 20850.,the Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742, and
| | - Guobing Chen
- the Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21224
| | - Nan-Ping Weng
- the Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland 21224
| | - Roy A Mariuzza
- From the University of Maryland Institute for Bioscience and Biotechnology Research, W. M. Keck Laboratory for Structural Biology, Rockville, Maryland 20850, .,the Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742, and
| |
Collapse
|
26
|
van den Heuvel H, Heutinck KM, van der Meer-Prins EMW, Yong SL, van Miert PPMC, Anholts JDH, Franke-van Dijk MEI, Zhang XQ, Roelen DL, Ten Berge RJM, Claas FHJ. Allo-HLA Cross-Reactivities of Cytomegalovirus-, Influenza-, and Varicella Zoster Virus-Specific Memory T Cells Are Shared by Different Healthy Individuals. Am J Transplant 2017; 17:2033-2044. [PMID: 28332333 DOI: 10.1111/ajt.14279] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/23/2017] [Accepted: 03/11/2017] [Indexed: 01/25/2023]
Abstract
Virus-specific T cells can recognize allogeneic HLA (allo-HLA) through TCR cross-reactivity. The allospecificity often differs by individual (private cross-reactivity) but also can be shared by multiple individuals (public cross-reactivity); however, only a few examples of the latter have been described. Because these could facilitate alloreactivity prediction in transplantation, we aimed to identify novel public cross-reactivities of human virus-specific CD8+ T cells directed against allo-HLA by assessing their reactivity in mixed-lymphocyte reactions. Further characterization was done by studying TCR usage with primer-based DNA sequencing, cytokine production with ELISAs, and cytotoxicity with 51 chromium-release assays. We identified three novel public allo-HLA cross-reactivities of human virus-specific CD8+ T cells. CMV B35/IPS CD8+ T cells cross-reacted with HLA-B51 and/or HLA-B58/B57 (23% of tetramer-positive individuals), FLU A2/GIL (influenza IMP[58-66] HLA-A*02:01/GILGFVFTL) CD8+ T cells with HLA-B38 (90% of tetramer-positive individuals), and VZV A2/ALW (varicella zoster virus IE62[593-601] HLA-A*02:01/ALWALPHAA) CD8+ T cells with HLA-B55 (two unrelated individuals). Cross-reactivity was tested against different cell types including endothelial and epithelial cells. All cross-reactive T cells expressed a memory phenotype, emphasizing the importance for transplantation. We conclude that public allo-HLA cross-reactivity of virus-specific memory T cells is not uncommon and may create novel opportunities for alloreactivity prediction and risk estimation in transplantation.
Collapse
Affiliation(s)
- H van den Heuvel
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - K M Heutinck
- Department of Experimental Immunology, Academic Medical Centre, Amsterdam, The Netherlands.,Renal Transplant Unit, Department of Internal Medicine, Division of Internal Medicine, Academic Medical Centre, Amsterdam, The Netherlands
| | - E M W van der Meer-Prins
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - S L Yong
- Department of Experimental Immunology, Academic Medical Centre, Amsterdam, The Netherlands.,Renal Transplant Unit, Department of Internal Medicine, Division of Internal Medicine, Academic Medical Centre, Amsterdam, The Netherlands
| | - P P M C van Miert
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - J D H Anholts
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - M E I Franke-van Dijk
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - X Q Zhang
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - D L Roelen
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - R J M Ten Berge
- Renal Transplant Unit, Department of Internal Medicine, Division of Internal Medicine, Academic Medical Centre, Amsterdam, The Netherlands
| | - F H J Claas
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
27
|
Dash P, Fiore-Gartland AJ, Hertz T, Wang GC, Sharma S, Souquette A, Crawford JC, Clemens EB, Nguyen THO, Kedzierska K, La Gruta NL, Bradley P, Thomas PG. Quantifiable predictive features define epitope-specific T cell receptor repertoires. Nature 2017. [PMID: 28636592 DOI: 10.1038/nature22383] [Citation(s) in RCA: 578] [Impact Index Per Article: 72.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
T cells are defined by a heterodimeric surface receptor, the T cell receptor (TCR), that mediates recognition of pathogen-associated epitopes through interactions with peptide and major histocompatibility complexes (pMHCs). TCRs are generated by genomic rearrangement of the germline TCR locus, a process termed V(D)J recombination, that has the potential to generate marked diversity of TCRs (estimated to range from 1015 (ref. 1) to as high as 1061 (ref. 2) possible receptors). Despite this potential diversity, TCRs from T cells that recognize the same pMHC epitope often share conserved sequence features, suggesting that it may be possible to predictively model epitope specificity. Here we report the in-depth characterization of ten epitope-specific TCR repertoires of CD8+ T cells from mice and humans, representing over 4,600 in-frame single-cell-derived TCRαβ sequence pairs from 110 subjects. We developed analytical tools to characterize these epitope-specific repertoires: a distance measure on the space of TCRs that permits clustering and visualization, a robust repertoire diversity metric that accommodates the low number of paired public receptors observed when compared to single-chain analyses, and a distance-based classifier that can assign previously unobserved TCRs to characterized repertoires with robust sensitivity and specificity. Our analyses demonstrate that each epitope-specific repertoire contains a clustered group of receptors that share core sequence similarities, together with a dispersed set of diverse 'outlier' sequences. By identifying shared motifs in core sequences, we were able to highlight key conserved residues driving essential elements of TCR recognition. These analyses provide insights into the generalizable, underlying features of epitope-specific repertoires and adaptive immune recognition.
Collapse
Affiliation(s)
- Pradyot Dash
- Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| | - Andrew J Fiore-Gartland
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
| | - Tomer Hertz
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.,The Shraga Segal Department of Microbiology, Immunology and Genetics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - George C Wang
- Division of Geriatric Medicine and Gerontology, Biology of Healthy Aging Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224, USA
| | - Shalini Sharma
- Department of Veterinary Physiology and Biochemistry, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana 125004, India
| | - Aisha Souquette
- Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| | - Jeremy Chase Crawford
- Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| | - E Bridie Clemens
- Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia
| | - Thi H O Nguyen
- Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia
| | - Katherine Kedzierska
- Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia
| | - Nicole L La Gruta
- Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia.,Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Philip Bradley
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.,Institute for Protein Design, University of Washington, Seattle, Washington 98195, USA
| | - Paul G Thomas
- Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| |
Collapse
|
28
|
Chen G, Yang X, Ko A, Sun X, Gao M, Zhang Y, Shi A, Mariuzza RA, Weng NP. Sequence and Structural Analyses Reveal Distinct and Highly Diverse Human CD8 + TCR Repertoires to Immunodominant Viral Antigens. Cell Rep 2017; 19:569-583. [PMID: 28423320 DOI: 10.1016/j.celrep.2017.03.072] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 02/02/2017] [Accepted: 03/24/2017] [Indexed: 01/07/2023] Open
Abstract
A diverse T cell receptor (TCR) repertoire is essential for controlling viral infections. However, information about TCR repertoires to defined viral antigens is limited. We performed a comprehensive analysis of CD8+ TCR repertoires for two dominant viral epitopes: pp65495-503 (NLV) of cytomegalovirus and M158-66 (GIL) of influenza A virus. The highly individualized repertoires (87-5,533 α or β clonotypes per subject) comprised thousands of unique TCRα and TCRβ sequences and dozens of distinct complementary determining region (CDR)3α and CDR3β motifs. However, diversity is effectively restricted by preferential V-J combinations, CDR3 lengths, and CDR3α/CDR3β pairings. Structures of two GIL-specific TCRs bound to GIL-HLA-A2 provided a potential explanation for the lower diversity of GIL-specific versus NLV-specific repertoires. These anti-viral TCRs occupied up to 3.4% of the CD8+ TCRβ repertoire, ensuring broad T cell responses to single epitopes. Our portrait of two anti-viral TCR repertoires may inform the development of predictors of immune protection.
Collapse
Affiliation(s)
- Guobing Chen
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Xinbo Yang
- W.M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA; Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Annette Ko
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Xiaoping Sun
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Mingming Gao
- W.M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA; Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Yongqing Zhang
- Laboratory of Genetics, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Alvin Shi
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Roy A Mariuzza
- W.M. Keck Laboratory for Structural Biology, University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD 20850, USA; Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Nan-Ping Weng
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, NIH, Baltimore, MD 21224, USA.
| |
Collapse
|
29
|
Broad TCR repertoire and diverse structural solutions for recognition of an immunodominant CD8 + T cell epitope. Nat Struct Mol Biol 2017; 24:395-406. [PMID: 28250417 PMCID: PMC5383516 DOI: 10.1038/nsmb.3383] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 01/30/2017] [Indexed: 12/16/2022]
Abstract
A keystone of antiviral immunity is CD8 T-cell recognition of viral peptides bound to MHC-I proteins. The recognition mode of individual T cell receptors (TCRs) has been studied in some detail, but how TCR variation functions in providing a robust response to viral antigen is unclear. The influenza M1 epitope is an immunodominant target of CD8 T cells helping to control influenza in HLA-A2+ individuals. Here, we show that many distinct TCRs are used by CD8 T cells to recognize HLA-A2/M1, encoding different structural solutions to the problem of specifically recognizing a relatively featureless peptide antigen. The vast majority of responding TCRs target small clefts between peptide and MHC. These broad repertoires lead to plasticity in antigen recognition and protection against T cell clonal loss and viral escape.
Collapse
|
30
|
Hoffmann T, Marion A, Antes I. DynaDom: structure-based prediction of T cell receptor inter-domain and T cell receptor-peptide-MHC (class I) association angles. BMC STRUCTURAL BIOLOGY 2017; 17:2. [PMID: 28148269 PMCID: PMC5289058 DOI: 10.1186/s12900-016-0071-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 12/29/2016] [Indexed: 11/22/2022]
Abstract
Background T cell receptor (TCR) molecules are involved in the adaptive immune response as they distinguish between self- and foreign-peptides, presented in major histocompatibility complex molecules (pMHC). Former studies showed that the association angles of the TCR variable domains (Vα/Vβ) can differ significantly and change upon binding to the pMHC complex. These changes can be described as a rotation of the domains around a general Center of Rotation, characterized by the interaction of two highly conserved glutamine residues. Methods We developed a computational method, DynaDom, for the prediction of TCR Vα/Vβ inter-domain and TCR/pMHC orientations in TCRpMHC complexes, which allows predicting the orientation of multiple protein-domains. In addition, we implemented a new approach to predict the correct orientation of the carboxamide endgroups in glutamine and asparagine residues, which can also be used as an external, independent tool. Results The approach was evaluated for the remodeling of 75 and 53 experimental structures of TCR and TCRpMHC (class I) complexes, respectively. We show that the DynaDom method predicts the correct orientation of the TCR Vα/Vβ angles in 96 and 89% of the cases, for the poses with the best RMSD and best interaction energy, respectively. For the concurrent prediction of the TCR Vα/Vβ and pMHC orientations, the respective rates reached 74 and 72%. Through an exhaustive analysis, we could show that the pMHC placement can be further improved by a straightforward, yet very time intensive extension of the current approach. Conclusions The results obtained in the present remodeling study prove the suitability of our approach for interdomain-angle optimization. In addition, the high prediction rate obtained specifically for the energetically highest ranked poses further demonstrates that our method is a powerful candidate for blind prediction. Therefore it should be well suited as part of any accurate atomistic modeling pipeline for TCRpMHC complexes and potentially other large molecular assemblies. Electronic supplementary material The online version of this article (doi:10.1186/s12900-016-0071-7) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Thomas Hoffmann
- Department of Biosciences and Center for Integrated Protein Science Munich, Technische Universität München, Emil-Erlenmeyer-Forum 8, 85354, Freising, Germany
| | - Antoine Marion
- Department of Biosciences and Center for Integrated Protein Science Munich, Technische Universität München, Emil-Erlenmeyer-Forum 8, 85354, Freising, Germany
| | - Iris Antes
- Department of Biosciences and Center for Integrated Protein Science Munich, Technische Universität München, Emil-Erlenmeyer-Forum 8, 85354, Freising, Germany.
| |
Collapse
|
31
|
Autoimmune susceptibility imposed by public TCRβ chains. Sci Rep 2016; 6:37543. [PMID: 27869234 PMCID: PMC5116635 DOI: 10.1038/srep37543] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 11/01/2016] [Indexed: 11/21/2022] Open
Abstract
Although the TCR repertoire is highly diverse, a small fraction of TCR chains, referred to as public, preferentially form and are shared by most individuals. Prior studies indicated that public TCRβ may be preferentially deployed in autoimmunity. We hypothesized that if these TCRβ modulate the likelihood of a TCRαβ heterodimer productively engaging autoantigen, because they are widely present in the population and often high frequency within individual repertoires, they could also broadly influence repertoire responsiveness to specific autoantigens. We assess this here using a series of public and private TCRβ derived from autoimmune encephalomyelitis-associated TCR. Transgenic expression of public, but not private, disease-associated TCRβ paired with endogenously rearranged TCRα endowed unprimed T cells with autoantigen reactivity. Further, two of six public, but none of five private TCRβ provoked spontaneous early-onset autoimmunity in mice. Our findings indicate that single TCRβ are sufficient to confer on TCRαβ chains reactivity toward disease-associated autoantigens in the context of diverse TCRα. They further suggest that public TCR can skew autoimmune susceptibility, and that subsets of public TCR sequences may serve as disease- specific biomarkers or therapeutic targets.
Collapse
|
32
|
Zhang H, Lim HS, Knapp B, Deane CM, Aleksic M, Dushek O, van der Merwe PA. The contribution of major histocompatibility complex contacts to the affinity and kinetics of T cell receptor binding. Sci Rep 2016; 6:35326. [PMID: 27734930 PMCID: PMC5062128 DOI: 10.1038/srep35326] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 09/28/2016] [Indexed: 11/09/2022] Open
Abstract
The interaction between the T cell antigen receptor (TCR) and antigenic peptide in complex with major histocompatibility complex (MHC) molecules is a crucial step in T cell activation. The relative contributions of TCR:peptide and TCR:MHC contacts to the overall binding energy remain unclear. This has important implications for our understanding of T cell development and function. In this study we used site directed mutagenesis to estimate the contribution of HLA-A2 side-chains to the binding of four TCRs. Our results show that these TCRs have very different energetic ‘footprints’ on HLA-A2, with no residues contributing to all TCR interactions. The estimated overall contribution of MHC side-chains to the total interaction energy was variable, with lower limits ranging from 11% to 50%. Kinetic analysis suggested a minor and variable contribution of MHC side-chains to the transition state complex, arguing against a two-step mechanism for TCR binding.
Collapse
Affiliation(s)
- Hao Zhang
- Sir William Dunn School of Pathology, University of Oxford, United Kingdom
| | - Hong-Sheng Lim
- Sir William Dunn School of Pathology, University of Oxford, United Kingdom
| | - Berhard Knapp
- Department of Statistics, University of Oxford, United Kingdom
| | | | - Milos Aleksic
- Sir William Dunn School of Pathology, University of Oxford, United Kingdom
| | - Omer Dushek
- Sir William Dunn School of Pathology, University of Oxford, United Kingdom
| | | |
Collapse
|
33
|
Grant EJ, Josephs TM, Valkenburg SA, Wooldridge L, Hellard M, Rossjohn J, Bharadwaj M, Kedzierska K, Gras S. Lack of Heterologous Cross-reactivity toward HLA-A*02:01 Restricted Viral Epitopes Is Underpinned by Distinct αβT Cell Receptor Signatures. J Biol Chem 2016; 291:24335-24351. [PMID: 27645996 DOI: 10.1074/jbc.m116.753988] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 09/11/2016] [Indexed: 11/06/2022] Open
Abstract
αβT cell receptor (TCR) genetic diversity is outnumbered by the quantity of pathogenic epitopes to be recognized. To provide efficient protective anti-viral immunity, a single TCR ideally needs to cross-react with a multitude of pathogenic epitopes. However, the frequency, extent, and mechanisms of TCR cross-reactivity remain unclear, with conflicting results on anti-viral T cell cross-reactivity observed in humans. Namely, both the presence and lack of T cell cross-reactivity have been reported with HLA-A*02:01-restricted epitopes from the Epstein-Barr and influenza viruses (BMLF-1 and M158, respectively) or with the hepatitis C and influenza viruses (NS31073 and NA231, respectively). Given the high sequence similarity of these paired viral epitopes (56 and 88%, respectively), the ubiquitous nature of the three viruses, and the high frequency of the HLA-A*02:01 allele, we selected these epitopes to establish the extent of T cell cross-reactivity. We combined ex vivo and in vitro functional assays, single-cell αβTCR repertoire sequencing, and structural analysis of these four epitopes in complex with HLA-A*02:01 to determine whether they could lead to heterologous T cell cross-reactivity. Our data show that sequence similarity does not translate to structural mimicry of the paired epitopes in complexes with HLA-A*02:01, resulting in induction of distinct αβTCR repertoires. The differences in epitope architecture might be an obstacle for TCR recognition, explaining the lack of T cell cross-reactivity observed. In conclusion, sequence similarity does not necessarily result in structural mimicry, and despite the need for cross-reactivity, antigen-specific TCR repertoires can remain highly specific.
Collapse
Affiliation(s)
- Emma J Grant
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia
| | - Tracy M Josephs
- the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, and; the Australian Research Council Centre of Excellence for Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Sophie A Valkenburg
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia
| | - Linda Wooldridge
- the Faculty of Health Sciences, University of Bristol, Bristol BS8 1TD, United Kingdom
| | - Margaret Hellard
- the Center for Research Excellence in Injecting Drug Use, Burnet Institute, Melbourne, Victoria 3004, Australia, and
| | - Jamie Rossjohn
- the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, and; the Australian Research Council Centre of Excellence for Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia,; the Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Mandvi Bharadwaj
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia
| | - Katherine Kedzierska
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia,.
| | - Stephanie Gras
- the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, and; the Australian Research Council Centre of Excellence for Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia,.
| |
Collapse
|
34
|
Cole DK, Bulek AM, Dolton G, Schauenberg AJ, Szomolay B, Rittase W, Trimby A, Jothikumar P, Fuller A, Skowera A, Rossjohn J, Zhu C, Miles JJ, Peakman M, Wooldridge L, Rizkallah PJ, Sewell AK. Hotspot autoimmune T cell receptor binding underlies pathogen and insulin peptide cross-reactivity. J Clin Invest 2016; 126:2191-204. [PMID: 27183389 PMCID: PMC4887163 DOI: 10.1172/jci85679] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/10/2016] [Indexed: 12/11/2022] Open
Abstract
The cross-reactivity of T cells with pathogen- and self-derived peptides has been implicated as a pathway involved in the development of autoimmunity. However, the mechanisms that allow the clonal T cell antigen receptor (TCR) to functionally engage multiple peptide–major histocompatibility complexes (pMHC) are unclear. Here, we studied multiligand discrimination by a human, preproinsulin reactive, MHC class-I–restricted CD8+ T cell clone (1E6) that can recognize over 1 million different peptides. We generated high-resolution structures of the 1E6 TCR bound to 7 altered peptide ligands, including a pathogen-derived peptide that was an order of magnitude more potent than the natural self-peptide. Evaluation of these structures demonstrated that binding was stabilized through a conserved lock-and-key–like minimal binding footprint that enables 1E6 TCR to tolerate vast numbers of substitutions outside of this so-called hotspot. Highly potent antigens of the 1E6 TCR engaged with a strong antipathogen-like binding affinity; this engagement was governed though an energetic switch from an enthalpically to entropically driven interaction compared with the natural autoimmune ligand. Together, these data highlight how T cell cross-reactivity with pathogen-derived antigens might break self-tolerance to induce autoimmune disease.
Collapse
Affiliation(s)
- David K. Cole
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Anna M. Bulek
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Garry Dolton
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Andrea J. Schauenberg
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Barbara Szomolay
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
- Mathematics Institute, University of Warwick, Coventry, United Kingdom
| | - William Rittase
- Woodruff School of Mechanical Engineering and Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Andrew Trimby
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Prithiviraj Jothikumar
- Woodruff School of Mechanical Engineering and Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Anna Fuller
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Ania Skowera
- Department of Immunobiology, King’s College London, London, United Kingdom
- NIHR Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London, London, United Kingdom
| | - Jamie Rossjohn
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, and
- ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia
| | - Cheng Zhu
- Woodruff School of Mechanical Engineering and Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - John J. Miles
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Mark Peakman
- Department of Immunobiology, King’s College London, London, United Kingdom
- NIHR Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London, London, United Kingdom
| | - Linda Wooldridge
- Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom
| | - Pierre J. Rizkallah
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Andrew K. Sewell
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| |
Collapse
|
35
|
Zhao Y, Nguyen P, Ma J, Wu T, Jones LL, Pei D, Cheng C, Geiger TL. Preferential Use of Public TCR during Autoimmune Encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2016; 196:4905-14. [PMID: 27183575 DOI: 10.4049/jimmunol.1501029] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 04/04/2016] [Indexed: 12/21/2022]
Abstract
How the TCR repertoire, in concert with risk-associated MHC, imposes susceptibility for autoimmune diseases is incompletely resolved. Due largely to recombinatorial biases, a small fraction of TCRα or β-chains are shared by most individuals, or public. If public TCR chains modulate a TCRαβ heterodimer's likelihood of productively engaging autoantigen, because they are pervasive and often high frequency, they could also broadly influence disease risk and progression. Prior data, using low-resolution techniques, have identified the heavy use of select public TCR in some autoimmune models. In this study, we assess public repertoire representation in mice with experimental autoimmune encephalomyelitis at high resolution. Saturation sequencing was used to identify >18 × 10(6) TCRβ sequences from the CNSs, periphery, and thymi of mice at different stages of autoimmune encephalomyelitis and healthy controls. Analyses indicated the prominent representation of a highly diverse public TCRβ repertoire in the disease response. Preferential formation of public TCR implicated in autoimmunity was identified in preselection thymocytes, and, consistently, public, disease-associated TCRβ were observed to be commonly oligoclonal. Increased TCR sharing and a focusing of the public TCR response was seen with disease progression. Critically, comparisons of peripheral and CNS repertoires and repertoires from preimmune and diseased mice demonstrated that public TCR were preferentially deployed relative to nonshared, or private, sequences. Our findings implicate public TCR in skewing repertoire response during autoimmunity and suggest that subsets of public TCR sequences may serve as disease-specific biomarkers or influence disease susceptibility or progression.
Collapse
Affiliation(s)
- Yunqian Zhao
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - Phuong Nguyen
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - Jing Ma
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - Tianhua Wu
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - Lindsay L Jones
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - Deqing Pei
- Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Cheng Cheng
- Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Terrence L Geiger
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| |
Collapse
|
36
|
Molecular basis for universal HLA-A*0201-restricted CD8+ T-cell immunity against influenza viruses. Proc Natl Acad Sci U S A 2016; 113:4440-5. [PMID: 27036003 DOI: 10.1073/pnas.1603106113] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Memory CD8(+)T lymphocytes (CTLs) specific for antigenic peptides derived from internal viral proteins confer broad protection against distinct strains of influenza A virus (IAV). However, immune efficacy can be undermined by the emergence of escape mutants. To determine how T-cell receptor (TCR) composition relates to IAV epitope variability, we used ex vivo peptide-HLA tetramer enrichment and single-cell multiplex analysis to compare TCRs targeted to the largely conserved HLA-A*0201-M158and the hypervariable HLA-B*3501-NP418antigens. The TCRαβs for HLA-B*3501-NP418 (+)CTLs varied among individuals and across IAV strains, indicating that a range of mutated peptides will prime different NP418-specific CTL sets. Conversely, a dominant public TRAV27/TRBV19(+)TCRαβ was selected in HLA-A*0201(+)donors responding to M158 This public TCR cross-recognized naturally occurring M158variants complexed with HLA-A*0201. Ternary structures showed that induced-fit molecular mimicry underpins TRAV27/TRBV19(+)TCR specificity for the WT and mutant M158peptides, suggesting the possibility of universal CTL immunity in HLA-A*0201(+)individuals. Combined with the high population frequency of HLA-A*0201, these data potentially explain the relative conservation of M158 Moreover, our results suggest that vaccination strategies aimed at generating broad protection should incorporate variant peptides to elicit cross-reactive responses against other specificities, especially those that may be relatively infrequent among IAV-primed memory CTLs.
Collapse
|
37
|
Covacu R, Philip H, Jaronen M, Almeida J, Kenison JE, Darko S, Chao CC, Yaari G, Louzoun Y, Carmel L, Douek DC, Efroni S, Quintana FJ. System-wide Analysis of the T Cell Response. Cell Rep 2016; 14:2733-44. [PMID: 26972015 PMCID: PMC4805488 DOI: 10.1016/j.celrep.2016.02.056] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 01/12/2016] [Accepted: 02/02/2016] [Indexed: 01/01/2023] Open
Abstract
The T cell receptor (TCR) controls the cellular adaptive immune response to antigens, but our understanding of TCR repertoire diversity and response to challenge is still incomplete. For example, TCR clones shared by different individuals with minimal alteration to germline gene sequences (public clones) are detectable in all vertebrates, but their significance is unknown. Although small in size, the zebrafish TCR repertoire is controlled by processes similar to those operating in mammals. Thus, we studied the zebrafish TCR repertoire and its response to stimulation with self and foreign antigens. We found that cross-reactive public TCRs dominate the T cell response, endowing a limited TCR repertoire with the ability to cope with diverse antigenic challenges. These features of vertebrate public TCRs might provide a mechanism for the rapid generation of protective T cell immunity, allowing a short temporal window for the development of more specific private T cell responses.
Collapse
Affiliation(s)
- Ruxandra Covacu
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Hagit Philip
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Merja Jaronen
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Jorge Almeida
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, US National Institutes of Health, Bethesda, MD 20892, USA
| | - Jessica E Kenison
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Samuel Darko
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, US National Institutes of Health, Bethesda, MD 20892, USA
| | - Chun-Cheih Chao
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Gur Yaari
- Bioengineering Program, Faculty of Engineering, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Yoram Louzoun
- Department of Mathematics, Bar-Ilan University, Ramat Gan 52900, Israel; Gonda Brain Research Center, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Liran Carmel
- Department of Genetics, The Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 91904, Israel
| | - Daniel C Douek
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, US National Institutes of Health, Bethesda, MD 20892, USA.
| | - Sol Efroni
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel.
| | - Francisco J Quintana
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| |
Collapse
|
38
|
Bello M, Correa-Basurto J. Energetic and flexibility properties captured by long molecular dynamics simulations of a membrane-embedded pMHCII-TCR complex. MOLECULAR BIOSYSTEMS 2016; 12:1350-66. [PMID: 26926952 DOI: 10.1039/c6mb00058d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Although crystallographic data have provided important molecular insight into the interactions in the pMHC-TCR complex, the inherent features of this structural approach cause it to only provide a static picture of the interactions. While unbiased molecular dynamics simulations (UMDSs) have provided important information about the dynamic structural behavior of the pMHC-TCR complex, most of them have modeled the pMHC-TCR complex as soluble, when in physiological conditions, this complex is membrane bound; therefore, following this latter UMDS protocol might hamper important dynamic results. In this contribution, we performed three independent 300 ns-long UMDSs of the pMHCII-TCR complex anchored in two opposing membranes to explore the structural and energetic properties of the recognition of pMHCII by the TCR. The conformational ensemble generated through UMDSs was subjected to clustering and Cartesian principal component analyses (cPCA) to explore the dynamical behavior of the pMHCII-TCR association. Furthermore, based on the conformational population sampled through UMDSs, the effective binding free energy, per-residue free energy decomposition, and alanine scanning mutations were explored for the native pMHCII-TCR complex, as well as for 12 mutations (p1-p12MHCII-TCR) introduced in the native peptide. Clustering analyses and cPCA provide insight into the rocking motion of the TCR onto pMHCII, together with the presence of new electrostatic interactions not observed through crystallographic methods. Energetic results provide evidence of the main contributors to the pMHC-TCR complex formation as well as the key residues involved in this molecular recognition process.
Collapse
Affiliation(s)
- Martiniano Bello
- Laboratorio de Modelado Molecular, Bioinformática y Diseño de Fármacos de la Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis Y Diaz Mirón S/N, Col. Casco de Santo Tomas, Mexico City, CP: 11340, Mexico.
| | | |
Collapse
|
39
|
Hoffmann T, Krackhardt AM, Antes I. Quantitative Analysis of the Association Angle between T-cell Receptor Vα/Vβ Domains Reveals Important Features for Epitope Recognition. PLoS Comput Biol 2015; 11:e1004244. [PMID: 26185983 PMCID: PMC4505886 DOI: 10.1371/journal.pcbi.1004244] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 03/17/2015] [Indexed: 02/01/2023] Open
Abstract
T-cell receptors (TCR) play an important role in the adaptive immune system as they recognize pathogen- or cancer-based epitopes and thus initiate the cell-mediated immune response. Therefore there exists a growing interest in the optimization of TCRs for medical purposes like adoptive T-cell therapy. However, the molecular mechanisms behind T-cell signaling are still predominantly unknown. For small sets of TCRs it was observed that the angle between their Vα- and Vβ-domains, which bind the epitope, can vary and might be important for epitope recognition. Here we present a comprehensive, quantitative study of the variation in the Vα/Vβ interdomain-angle and its influence on epitope recognition, performing a systematic bioinformatics analysis based on a representative set of experimental TCR structures. For this purpose we developed a new, cuboid-based superpositioning method, which allows a unique, quantitative analysis of the Vα/Vβ-angles. Angle-based clustering led to six significantly different clusters. Analysis of these clusters revealed the unexpected result that the angle is predominantly influenced by the TCR-clonotype, whereas the bound epitope has only a minor influence. Furthermore we could identify a previously unknown center of rotation (CoR), which is shared by all TCRs. All TCR geometries can be obtained by rotation around this center, rendering it a new, common TCR feature with the potential of improving the accuracy of TCR structure prediction considerably. The importance of Vα/Vβ rotation for signaling was confirmed as we observed larger variances in the Vα/Vβ-angles in unbound TCRs compared to epitope-bound TCRs. Our results strongly support a two-step mechanism for TCR-epitope: First, preformation of a flexible TCR geometry in the unbound state and second, locking of the Vα/Vβ-angle in a TCR-type specific geometry upon epitope-MHC association, the latter being driven by rotation around the unique center of rotation. The recognition of antigenic peptides by cytotoxic T-cells is one of the crucial steps during the adaptive immune response. Thus a detailed understanding of this process is not only important for elucidating the mechanism behind T-cell signaling, but also for various emerging new medical applications like T-cell based immunotherapies and designed bio-therapeutics. However, despite the fast growing interest in this field, the mechanistic basis of the immune response is still largely unknown. Previous qualitative studies suggested that the T-cell receptor (TCR) Vα/Vβ-interdomain angle plays a crucial role in epitope recognition as it predetermines the relative position of its antigen-recognizing CDR1-3 loops and thus TCR specificity. In the manuscript we present a systematic bioinformatic analysis of the structural characteristics of bound and unbound TCR molecules focusing on the Vα/Vβ-angle. Our results demonstrate the importance of this angle for signaling, as several distinct Vα/Vβ-angle based structural clusters could be observed and larger angle flexibilities exist for unbound TCRs than for bound TCRs, providing quantitative proof for a two-step locking mechanism upon epitope recognition. In this context, we could identify a unique rotational point, which allows a quantitative, yet intuitive description of all observed angle variations and the structural changes upon epitope binding.
Collapse
MESH Headings
- Binding Sites
- Computer Simulation
- Epitope Mapping/methods
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/ultrastructure
- Models, Chemical
- Models, Immunological
- Models, Molecular
- Protein Binding
- Protein Conformation
- Protein Structure, Tertiary
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, alpha-beta/ultrastructure
Collapse
Affiliation(s)
- Thomas Hoffmann
- Department of Biosciences and Center for Integrated Protein Science Munich,Technische Universität München, Freising-Weihenstephan, Germany
| | - Angela M. Krackhardt
- Medizinische Klinik III, Innere Medizin mit Schwerpunkt Hämatologie und Onkologie, Technische Universität München, Munich, Germany
- Clinical Cooperation Group, Antigen specific T cell therapy, Helmholtz Zentrum München (GmbH), German Center for Environmental Health, Munich, Germany
- German Cancer Consortium (DKTK), Munich, Germany
| | - Iris Antes
- Department of Biosciences and Center for Integrated Protein Science Munich,Technische Universität München, Freising-Weihenstephan, Germany
- * E-mail:
| |
Collapse
|
40
|
Rödström KEJ, Regenthal P, Lindkvist-Petersson K. Structure of Staphylococcal Enterotoxin E in Complex with TCR Defines the Role of TCR Loop Positioning in Superantigen Recognition. PLoS One 2015; 10:e0131988. [PMID: 26147596 PMCID: PMC4492778 DOI: 10.1371/journal.pone.0131988] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 06/09/2015] [Indexed: 11/18/2022] Open
Abstract
T cells are crucial players in cell-mediated immunity. The specificity of their receptor, the T cell receptor (TCR), is central for the immune system to distinguish foreign from host antigens. Superantigens are bacterial toxins capable of inducing a toxic immune response by cross-linking the TCR and the major histocompatibility complex (MHC) class II and circumventing the antigen specificity. Here, we present the structure of staphylococcal enterotoxin E (SEE) in complex with a human T cell receptor, as well as the unligated T cell receptor structure. There are clear structural changes in the TCR loops upon superantigen binding. In particular, the HV4 loop moves to circumvent steric clashes upon complex formation. In addition, a predicted ternary model of SEE in complex with both TCR and MHC class II displays intermolecular contacts between the TCR α-chain and the MHC, suggesting that the TCR α-chain is of importance for complex formation.
Collapse
Affiliation(s)
- Karin E. J. Rödström
- Department of Experimental Medical Science, Lund University, BMC C13, 22 184, Lund, Sweden
| | - Paulina Regenthal
- Department of Experimental Medical Science, Lund University, BMC C13, 22 184, Lund, Sweden
| | | |
Collapse
|
41
|
Pauza CD, Cairo C. Evolution and function of the TCR Vgamma9 chain repertoire: It's good to be public. Cell Immunol 2015; 296:22-30. [PMID: 25769734 PMCID: PMC4466227 DOI: 10.1016/j.cellimm.2015.02.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 02/11/2015] [Accepted: 02/17/2015] [Indexed: 01/17/2023]
Abstract
Lymphocytes expressing a T cell receptor (TCR) composed of Vgamma9 and Vdelta2 chains represent a minor fraction of human thymocytes. Extrathymic selection throughout post-natal life causes the proportion of cells with a Vgamma9-JP rearrangement to increase and elevates the capacity for responding to non-peptidic phosphoantigens. Extrathymic selection is so powerful that phosphoantigen-reactive cells comprise about 1 in 40 circulating memory T cells in healthy adults and the subset expands rapidly upon infection or in response to malignancy. Skewing of the gamma delta TCR repertoire is accompanied by selection for public gamma chain sequences such that many unrelated individuals overlap extensive in their circulating repertoire. This type of selection implies the presence of a monomorphic antigen-presenting molecule that is an object of current research but remains incompletely defined. While selection on a monomorphic presenting molecule may seem unusual, similar mechanisms shape the alpha beta T cell repertoire including the extreme examples of NKT or mucosal-associated invariant T cells (MAIT) and the less dramatic amplification of public Vbeta chain rearrangements driven by individual MHC molecules and associated with resistance to viral pathogens. Selecting and amplifying public T cell receptors whether alpha beta or gamma delta, are important steps in developing an anticipatory TCR repertoire. Cell clones expressing public TCR can accelerate the kinetics of response to pathogens and impact host survival.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- CD4-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/immunology
- Evolution, Molecular
- Humans
- Immunologic Memory/immunology
- Natural Killer T-Cells/immunology
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/immunology
- Sequence Homology
- T-Lymphocyte Subsets/immunology
- Thymocytes/immunology
Collapse
Affiliation(s)
- C David Pauza
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| | - Cristiana Cairo
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| |
Collapse
|
42
|
Murray JS. An old Twist in HLA-A: CDR3α Hook up at an R65-joint. Front Immunol 2015; 6:268. [PMID: 26074926 PMCID: PMC4445401 DOI: 10.3389/fimmu.2015.00268] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 05/14/2015] [Indexed: 11/30/2022] Open
Abstract
T-cell ontogeny optimizes the α/β T-cell receptor (TCR) repertoire for recognition of major histocompatibility complex (MHC) class-I/II genetic polymorphism, and co-evolution of TCR germline V-gene segments and the MHC must entail somatic diversity generated in the third complimentary determining regions (CDR3α/β); however, it is still not clear how. Herein, a conspicuous structural link between the V-Jα used by several different TCR [all in complex with the same MHC molecule (HLA-A2)], and a conserved MHC motif (a.a., R65-X-X-K-A-X-S-Q72) is described. We model this R65-joint in detail, and show that the same TCR’s CDR3α loop maintains its CDR2α loop at a distance of ~4 Å from polymorphic amino acid (a.a.) positions of the α-2 helix in all but one of the analyzed crystal structures. Indeed, the pitch of docked TCRs varies as their twist/tilt/sway maintains the R65-joint and peptide contacts. Thus, the R65-joint appears to have poised the HLA-A lineage toward alloreactivity.
Collapse
|
43
|
Kløverpris HN, McGregor R, McLaren JE, Ladell K, Harndahl M, Stryhn A, Carlson JM, Koofhethile C, Gerritsen B, Keşmir C, Chen F, Riddell L, Luzzi G, Leslie A, Walker BD, Ndung'u T, Buus S, Price DA, Goulder PJ. CD8+ TCR Bias and Immunodominance in HIV-1 Infection. THE JOURNAL OF IMMUNOLOGY 2015; 194:5329-45. [PMID: 25911754 DOI: 10.4049/jimmunol.1400854] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 02/25/2015] [Indexed: 12/25/2022]
Abstract
Immunodominance describes a phenomenon whereby the immune system consistently targets only a fraction of the available Ag pool derived from a given pathogen. In the case of CD8(+) T cells, these constrained epitope-targeting patterns are linked to HLA class I expression and determine disease progression. Despite the biological importance of these predetermined response hierarchies, little is known about the factors that control immunodominance in vivo. In this study, we conducted an extensive analysis of CD8(+) T cell responses restricted by a single HLA class I molecule to evaluate the mechanisms that contribute to epitope-targeting frequency and antiviral efficacy in HIV-1 infection. A clear immunodominance hierarchy was observed across 20 epitopes restricted by HLA-B*42:01, which is highly prevalent in populations of African origin. Moreover, in line with previous studies, Gag-specific responses and targeting breadth were associated with lower viral load set-points. However, peptide-HLA-B*42:01 binding affinity and stability were not significantly linked with targeting frequencies. Instead, immunodominance correlated with epitope-specific usage of public TCRs, defined as amino acid residue-identical TRB sequences that occur in multiple individuals. Collectively, these results provide important insights into a potential link between shared TCR recruitment, immunodominance, and antiviral efficacy in a major human infection.
Collapse
Affiliation(s)
- Henrik N Kløverpris
- Department of Paediatrics, University of Oxford, Oxford OX1 3SY, United Kingdom; Department of International Health, Immunology, and Microbiology, University of Copenhagen, 2200-Copenhagen N, Denmark; KwaZulu-Natal Research Institute for Tuberculosis and HIV, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban 4001, South Africa;
| | - Reuben McGregor
- Department of Paediatrics, University of Oxford, Oxford OX1 3SY, United Kingdom
| | - James E McLaren
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Kristin Ladell
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Mikkel Harndahl
- Department of International Health, Immunology, and Microbiology, University of Copenhagen, 2200-Copenhagen N, Denmark
| | - Anette Stryhn
- Department of International Health, Immunology, and Microbiology, University of Copenhagen, 2200-Copenhagen N, Denmark
| | | | - Catherine Koofhethile
- HIV Pathogenesis Program, Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban 4013, South Africa
| | - Bram Gerritsen
- Theoretical Biology Group, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Can Keşmir
- Theoretical Biology Group, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Fabian Chen
- Department of Sexual Health, Royal Berkshire Hospital, Reading RG1 5AN, United Kingdom
| | - Lynn Riddell
- Department of Genitourinary Medicine, Northamptonshire Healthcare National Health Service Trust, Northampton General Hospital, Cliftonville, Northampton NN1 5BD, United Kingdom
| | - Graz Luzzi
- Department of Sexual Health, Wycombe Hospital, High Wycombe HP11 2TT, United Kingdom
| | - Alasdair Leslie
- KwaZulu-Natal Research Institute for Tuberculosis and HIV, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban 4001, South Africa
| | - Bruce D Walker
- Ragon Institute of MGH, MIT, and Harvard, Boston, MA 02129; Howard Hughes Medical Institute, Chevy Chase, MD 20815; and
| | - Thumbi Ndung'u
- KwaZulu-Natal Research Institute for Tuberculosis and HIV, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban 4001, South Africa; HIV Pathogenesis Program, Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban 4013, South Africa; Max Planck Institute for Infection Biology, D-10117 Berlin, Germany
| | - Søren Buus
- Department of International Health, Immunology, and Microbiology, University of Copenhagen, 2200-Copenhagen N, Denmark
| | - David A Price
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Philip J Goulder
- Department of Paediatrics, University of Oxford, Oxford OX1 3SY, United Kingdom
| |
Collapse
|
44
|
Physical detection of influenza A epitopes identifies a stealth subset on human lung epithelium evading natural CD8 immunity. Proc Natl Acad Sci U S A 2015; 112:2151-6. [PMID: 25646416 DOI: 10.1073/pnas.1423482112] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Vaccines eliciting immunity against influenza A viruses (IAVs) are currently antibody-based with hemagglutinin-directed antibody titer the only universally accepted immune correlate of protection. To investigate the disconnection between observed CD8 T-cell responses and immunity to IAV, we used a Poisson liquid chromatography data-independent acquisition MS method to physically detect PR8/34 (H1N1), X31 (H3N2), and Victoria/75 (H3N2) epitopes bound to HLA-A*02:01 on human epithelial cells following in vitro infection. Among 32 PR8 peptides (8-10mers) with predicted IC50 < 60 nM, 9 were present, whereas 23 were absent. At 18 h postinfection, epitope copies per cell varied from a low of 0.5 for M13-11 to a high of >500 for M1(58-66) with PA, HA, PB1, PB2, and NA epitopes also detected. However, aside from M1(58-66), natural CD8 memory responses against conserved presented epitopes were either absent or only weakly observed by blood Elispot. Moreover, the functional avidities of the immunodominant M1(58-66)/HLA-A*02:01-specific T cells were so poor as to be unable to effectively recognize infected human epithelium. Analysis of T-cell responses to primary PR8 infection in HLA-A*02:01 transgenic B6 mice underscores the poor avidity of T cells recognizing M1(58-66). By maintaining high levels of surface expression of this epitope on epithelial and dendritic cells, the virus exploits the combination of immunodominance and functional inadequacy to evade HLA-A*02:01-restricted T-cell immunity. A rational approach to CD8 vaccines must characterize processing and presentation of pathogen-derived epitopes as well as resultant immune responses. Correspondingly, vaccines may be directed against "stealth" epitopes, overriding viral chicanery.
Collapse
|
45
|
Narrowing of human influenza A virus-specific T cell receptor α and β repertoires with increasing age. J Virol 2015; 89:4102-16. [PMID: 25609818 DOI: 10.1128/jvi.03020-14] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED Alterations in memory CD8 T cell responses may contribute to the high morbidity and mortality caused by seasonal influenza A virus (IAV) infections in older individuals. We questioned whether memory CD8 responses to this nonpersistent virus, to which recurrent exposure with new strains is common, changed over time with increasing age. Here, we show a direct correlation between increasing age and narrowing of the HLA-A2-restricted IAV Vα and Vβ T cell repertoires specific to M1 residues 58 to 66 (M158-66), which simultaneously lead to oligoclonal expansions, including the usage of a single identical VA12-JA29 clonotype in all eight older donors. The Vα repertoire of older individuals also had longer CDR3 regions with increased usage of G/A runs, whose molecular flexibility may enhance T cell receptor (TCR) promiscuity. Collectively, these results suggest that CD8 memory T cell responses to nonpersistent viruses like IAV in humans are dynamic, and with aging there is a reduced diversity but a preferential retention of T cell repertoires with features of enhanced cross-reactivity. IMPORTANCE With increasing age, the immune system undergoes drastic changes, and older individuals have declined resistance to infections. Vaccinations become less effective, and infection with influenza A virus in older individuals is associated with higher morbidity and mortality. Here, we questioned whether T cell responses directed against the highly conserved HLA-A2-restricted M158-66 peptide of IAV evolves with increasing age. Specifically, we postulated that CD8 T cell repertoires narrow with recurrent exposure and may thus be less efficient in response to new infections with new strains of IAV. Detailed analyses of the VA and VB TCR repertoires simultaneously showed a direct correlation between increasing age and narrowing of the TCR repertoire. Features of the TCRs indicated potentially enhanced cross-reactivity in all older donors. In summary, T cell repertoire analysis in older individuals may be useful as one of the predictors of protection after vaccination.
Collapse
|
46
|
Rossjohn J, Gras S, Miles JJ, Turner SJ, Godfrey DI, McCluskey J. T cell antigen receptor recognition of antigen-presenting molecules. Annu Rev Immunol 2014; 33:169-200. [PMID: 25493333 DOI: 10.1146/annurev-immunol-032414-112334] [Citation(s) in RCA: 564] [Impact Index Per Article: 51.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The Major Histocompatibility Complex (MHC) locus encodes classical MHC class I and MHC class II molecules and nonclassical MHC-I molecules. The architecture of these molecules is ideally suited to capture and present an array of peptide antigens (Ags). In addition, the CD1 family members and MR1 are MHC class I-like molecules that bind lipid-based Ags and vitamin B precursors, respectively. These Ag-bound molecules are subsequently recognized by T cell antigen receptors (TCRs) expressed on the surface of T lymphocytes. Structural and associated functional studies have been highly informative in providing insight into these interactions, which are crucial to immunity, and how they can lead to aberrant T cell reactivity. Investigators have determined over thirty unique TCR-peptide-MHC-I complex structures and twenty unique TCR-peptide-MHC-II complex structures. These investigations have shown a broad consensus in docking geometry and provided insight into MHC restriction. Structural studies on TCR-mediated recognition of lipid and metabolite Ags have been mostly confined to TCRs from innate-like natural killer T cells and mucosal-associated invariant T cells, respectively. These studies revealed clear differences between TCR-lipid-CD1, TCR-metabolite-MR1, and TCR-peptide-MHC recognition. Accordingly, TCRs show remarkable structural and biological versatility in engaging different classes of Ag that are presented by polymorphic and monomorphic Ag-presenting molecules of the immune system.
Collapse
Affiliation(s)
- Jamie Rossjohn
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia; ,
| | | | | | | | | | | |
Collapse
|
47
|
Understanding the structural dynamics of TCR-pMHC interactions. Trends Immunol 2014; 35:604-612. [DOI: 10.1016/j.it.2014.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 10/20/2014] [Accepted: 10/20/2014] [Indexed: 12/23/2022]
|
48
|
Reiser JB, Legoux F, Gras S, Trudel E, Chouquet A, Léger A, Le Gorrec M, Machillot P, Bonneville M, Saulquin X, Housset D. Analysis of relationships between peptide/MHC structural features and naive T cell frequency in humans. THE JOURNAL OF IMMUNOLOGY 2014; 193:5816-26. [PMID: 25392532 DOI: 10.4049/jimmunol.1303084] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The structural rules governing peptide/MHC (pMHC) recognition by T cells remain unclear. To address this question, we performed a structural characterization of several HLA-A2/peptide complexes and assessed in parallel their antigenicity, by analyzing the frequency of the corresponding Ag-specific naive T cells in A2(+) and A2(-) individuals, as well as within CD4(+) and CD8(+) subsets. We were able to find a correlation between specific naive T cell frequency and peptide solvent accessibility and/or mobility for a subset of moderately prominent peptides. However, one single structural parameter of the pMHC complexes could not be identified to explain each peptide antigenicity. Enhanced pMHC antigenicity was associated with both highly biased TRAV usage, possibly reflecting favored interaction between particular pMHC complexes and germline TRAV loops, and peptide structural features allowing interactions with a broad range of permissive CDR3 loops. In this context of constrained TCR docking mode, an optimal peptide solvent exposed surface leading to an optimal complementarity with TCR interface may constitute one of the key features leading to high frequency of specific T cells. Altogether our results suggest that frequency of specific T cells depends on the fine-tuning of several parameters, the structural determinants governing TCR-pMHC interaction being just one of them.
Collapse
Affiliation(s)
- Jean-Baptiste Reiser
- Université de Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France; Commissariat à l'énergie atomique et aux énergies alternatives, Direction des sciences du vivant, Institut de Biologie Structurale, F-38044 Grenoble, France; Centre national de la recherche scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - François Legoux
- Institut national de la santé et de la recherche médicale, Unité mixte de recherche 892, Centre de Recherche en Cancérologie Nantes Angers, F-44000 Nantes, France; and
| | - Stéphanie Gras
- Université de Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France; Commissariat à l'énergie atomique et aux énergies alternatives, Direction des sciences du vivant, Institut de Biologie Structurale, F-38044 Grenoble, France; Centre national de la recherche scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Eric Trudel
- Université de Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France; Commissariat à l'énergie atomique et aux énergies alternatives, Direction des sciences du vivant, Institut de Biologie Structurale, F-38044 Grenoble, France; Centre national de la recherche scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Anne Chouquet
- Université de Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France; Commissariat à l'énergie atomique et aux énergies alternatives, Direction des sciences du vivant, Institut de Biologie Structurale, F-38044 Grenoble, France; Centre national de la recherche scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Alexandra Léger
- Institut national de la santé et de la recherche médicale, Unité mixte de recherche 892, Centre de Recherche en Cancérologie Nantes Angers, F-44000 Nantes, France; and
| | - Madalen Le Gorrec
- Université de Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France; Commissariat à l'énergie atomique et aux énergies alternatives, Direction des sciences du vivant, Institut de Biologie Structurale, F-38044 Grenoble, France; Centre national de la recherche scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Paul Machillot
- Université de Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France; Commissariat à l'énergie atomique et aux énergies alternatives, Direction des sciences du vivant, Institut de Biologie Structurale, F-38044 Grenoble, France; Centre national de la recherche scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Marc Bonneville
- Institut national de la santé et de la recherche médicale, Unité mixte de recherche 892, Centre de Recherche en Cancérologie Nantes Angers, F-44000 Nantes, France; and
| | - Xavier Saulquin
- Institut national de la santé et de la recherche médicale, Unité mixte de recherche 892, Centre de Recherche en Cancérologie Nantes Angers, F-44000 Nantes, France; and Université de Nantes, F-44000 Nantes, France
| | - Dominique Housset
- Université de Grenoble Alpes, Institut de Biologie Structurale, F-38044 Grenoble, France; Commissariat à l'énergie atomique et aux énergies alternatives, Direction des sciences du vivant, Institut de Biologie Structurale, F-38044 Grenoble, France; Centre national de la recherche scientifique, Institut de Biologie Structurale, F-38044 Grenoble, France;
| |
Collapse
|
49
|
Dourado DFAR, Flores SC. A multiscale approach to predicting affinity changes in protein-protein interfaces. Proteins 2014; 82:2681-90. [PMID: 24975440 DOI: 10.1002/prot.24634] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 06/12/2014] [Accepted: 06/18/2014] [Indexed: 11/07/2022]
Abstract
Substitution mutations in protein-protein interfaces can have a substantial effect on binding, which has consequences in basic and applied biomedical research. Experimental expression, purification, and affinity determination of protein complexes is an expensive and time-consuming means of evaluating the effect of mutations, making a fast and accurate in silico method highly desirable. When the structure of the wild-type complex is known, it is possible to economically evaluate the effect of point mutations with knowledge based potentials, which do not model backbone flexibility, but these have been validated only for single mutants. Substitution mutations tend to induce local conformational rearrangements only. Accordingly, ZEMu (Zone Equilibration of Mutants) flexibilizes only a small region around the site of mutation, then computes its dynamics under a physics-based force field. We validate with 1254 experimental mutants (with 1-15 simultaneous substitutions) in a wide variety of different protein environments (65 protein complexes), and obtain a significant improvement in the accuracy of predicted ΔΔG.
Collapse
Affiliation(s)
- Daniel F A R Dourado
- Department of Cell and Molecular Biology, Computational and Systems Biology, Uppsala University, 751 24, Uppsala, Sweden
| | | |
Collapse
|
50
|
Burrows SR, Miles JJ. Immune parameters to consider when choosing T-cell receptors for therapy. Front Immunol 2013; 4:229. [PMID: 23935599 PMCID: PMC3733007 DOI: 10.3389/fimmu.2013.00229] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Accepted: 07/22/2013] [Indexed: 11/13/2022] Open
Abstract
T-cell receptor (TCR) therapy has arrived as a realistic treatment option for many human diseases. TCR gene therapy allows for the mass redirection of T-cells against a defined antigen while high affinity TCR engineering allows for the creation of a new class of soluble drugs. However, deciding which TCR blueprint to take forward for gene therapy or engineering is difficult. More than one quintillion TCR combinations can be generated by somatic recombination and we are only now beginning to appreciate that not all are functionally equal. TCRs can exhibit high or low degrees of HLA-restricted cross-reactivity and alloreact against one or a combination of HLA alleles. Identifying TCR candidates with high specificity and minimal cross-reactivity/alloreactivity footprints before engineering is obviously highly desirable. Here we will summarize what we currently know about TCR biology with regard to immunoengineering.
Collapse
Affiliation(s)
- Scott R Burrows
- Human Immunity Laboratory and Cellular Immunology Laboratory, Queensland Institute of Medical Research , Brisbane, QLD , Australia ; School of Medicine, The University of Queensland , Brisbane, QLD , Australia
| | | |
Collapse
|