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Timilsina U, Ivey EB, Duffy S, Plianchaisuk A, The Genotype to Phenotype Japan (G2P-Japan) Consortium, Ito J, Sato K, Stavrou S. SARS-CoV-2 ORF7a Mutation Found in BF.5 and BF.7 Sublineages Impacts Its Functions. Int J Mol Sci 2024; 25:2351. [PMID: 38397027 PMCID: PMC10889720 DOI: 10.3390/ijms25042351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 02/06/2024] [Accepted: 02/09/2024] [Indexed: 02/25/2024] Open
Abstract
A feature of the SARS-CoV-2 Omicron subvariants BF.5 and BF.7 that recently circulated mainly in China and Japan was the high prevalence of the ORF7a: H47Y mutation, in which the 47th residue of ORF7a has been mutated from a histidine (H) to a tyrosine (Y). Here, we evaluated the effect of this mutation on the three main functions ascribed to the SARS-CoV-2 ORF7a protein. Our findings show that H47Y mutation impairs the ability of SARS-CoV-2 ORF7a to antagonize the type I interferon (IFN-I) response and to downregulate major histocompatibility complex I (MHC-I) cell surface levels, but had no effect in its anti-SERINC5 function. Overall, our results suggest that the H47Y mutation of ORF7a affects important functions of this protein, resulting in changes in virus pathogenesis.
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Affiliation(s)
- Uddhav Timilsina
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA; (U.T.); (E.B.I.); (S.D.)
| | - Emily B. Ivey
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA; (U.T.); (E.B.I.); (S.D.)
| | - Sean Duffy
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA; (U.T.); (E.B.I.); (S.D.)
| | - Arnon Plianchaisuk
- Division of Systems Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8369, Japan; (A.P.); (J.I.); (K.S.)
| | | | - Jumpei Ito
- Division of Systems Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8369, Japan; (A.P.); (J.I.); (K.S.)
| | - Kei Sato
- Division of Systems Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8369, Japan; (A.P.); (J.I.); (K.S.)
- International Research Center for Infectious Diseases, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8369, Japan
- Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8581, Japan
- International Vaccine Design Center, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
- Collaboration Unit for Infection, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto 860-0862, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi 332-0012, Japan
| | - Spyridon Stavrou
- Department of Microbiology and Immunology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA; (U.T.); (E.B.I.); (S.D.)
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2
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Ramalingam PS, Arumugam S. Reverse vaccinology and immunoinformatics approaches to design multi-epitope based vaccine against oncogenic KRAS. Med Oncol 2023; 40:283. [PMID: 37644143 DOI: 10.1007/s12032-023-02160-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 08/12/2023] [Indexed: 08/31/2023]
Abstract
Mutant KRAS-induced tumorigenesis is highly involved in the progression of pancreatic, lung, and breast cancer. Comparatively, KRAS G12D and KRAS G12C are the most frequent mutations that promote cancer progression and aggressiveness. Although KRAS mutant inhibitors exhibit significant therapeutic potential, day by day, they are becoming resistant among patients. Multi-epitope based cancer vaccines are a promising alternative strategy that induces an immune response against tumor antigens. In the present study, we have designed, constructed, and validated a novel multi-epitope vaccine construct against KRAS G12D and G12C mutants using reverse vaccinology and immunoinformatics approaches. In addition, the vaccine construct was structurally refined and showed significant physiochemical properties, and could induce an immune response. Furthermore, the optimized vaccine construct was cloned into a pET‑28a (+) expression vector through in silico cloning. Conclusively, the multi-epitope vaccine construct is structurally stable, soluble, antigenic, non‑allergic, and non‑toxic. Further, it has to be studied in in vitro and in vivo to evaluate its therapeutic efficacy against KRAS-mutated cancers in the near future.
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Affiliation(s)
| | - Sivakumar Arumugam
- Protein Engineering Lab, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India.
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3
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Finton KAK, Rupert PB, Friend DJ, Dinca A, Lovelace ES, Buerger M, Rusnac DV, Foote-McNabb U, Chour W, Heath JR, Campbell JS, Pierce RH, Strong RK. Effects of HLA single chain trimer design on peptide presentation and stability. Front Immunol 2023; 14:1170462. [PMID: 37207206 PMCID: PMC10189100 DOI: 10.3389/fimmu.2023.1170462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/21/2023] [Indexed: 05/21/2023] Open
Abstract
MHC class I "single-chain trimer" molecules, coupling MHC heavy chain, β2-microglobulin, and a specific peptide into a single polypeptide chain, are widely used in research. To more fully understand caveats associated with this design that may affect its use for basic and translational studies, we evaluated a set of engineered single-chain trimers with combinations of stabilizing mutations across eight different classical and non-classical human class I alleles with 44 different peptides, including a novel human/murine chimeric design. While, overall, single-chain trimers accurately recapitulate native molecules, care was needed in selecting designs for studying peptides longer or shorter than 9-mers, as single-chain trimer design could affect peptide conformation. In the process, we observed that predictions of peptide binding were often discordant with experiment and that yields and stabilities varied widely with construct design. We also developed novel reagents to improve the crystallizability of these proteins and confirmed novel modes of peptide presentation.
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Affiliation(s)
- Kathryn A. K. Finton
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
| | - Peter B. Rupert
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
| | - Della J. Friend
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
| | - Ana Dinca
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, United States
| | - Erica S. Lovelace
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
| | - Matthew Buerger
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
| | - Domnita V. Rusnac
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
| | - Ulysses Foote-McNabb
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
| | - William Chour
- Institute for Systems Biology, Seattle, WA, United States
| | - James R. Heath
- Institute for Systems Biology, Seattle, WA, United States
| | - Jean S. Campbell
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, United States
| | - Robert H. Pierce
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, United States
| | - Roland K. Strong
- Division of Basic Science, Fred Hutchinson Cancer Research Center (FHCC), Seattle, WA, United States
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4
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Gupta S, Nerli S, Kandy SK, Mersky GL, Sgourakis NG. HLA3DB: comprehensive annotation of peptide/HLA complexes enables blind structure prediction of T cell epitopes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533510. [PMID: 36993660 PMCID: PMC10055217 DOI: 10.1101/2023.03.20.533510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
The class I proteins of the major histocompatibility complex (MHC-I) display epitopic peptides derived from endogenous proteins on the cell surface for immune surveillance. Accurate modeling of peptide/HLA (pHLA, the human MHC) structures has been mired by conformational diversity of the central peptide residues, which are critical for recognition by T cell receptors. Here, analysis of X-ray crystal structures within a curated database (HLA3DB) shows that pHLA complexes encompassing multiple HLA allotypes present a discrete set of peptide backbone conformations. Leveraging these representative backbones, we employ a regression model trained on terms of a physically relevant energy function to develop a comparative modeling approach for nonamer peptide/HLA structures named RepPred. Our method outperforms the top pHLA modeling approach by up to 19% in terms of structural accuracy, and consistently predicts blind targets not included in our training set. Insights from our work provide a framework for linking conformational diversity with antigen immunogenicity and receptor cross-reactivity.
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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).
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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
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6
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Feng L, Gao YY, Sun M, Li ZB, Zhang Q, Yang J, Qiao C, Jin H, Feng HS, Xian YH, Qi J, Gao GF, Liu WJ, Gao FS. The Parallel Presentation of Two Functional CTL Epitopes Derived from the O and Asia 1 Serotypes of Foot-and-Mouth Disease Virus and Swine SLA-2*HB01: Implications for Universal Vaccine Development. Cells 2022; 11:cells11244017. [PMID: 36552780 PMCID: PMC9777387 DOI: 10.3390/cells11244017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
Foot-and-mouth disease virus (FMDV) poses a significant threat to the livestock industry. Through their recognition of the conserved epitopes presented by the swine leukocyte antigen (SLA), T cells play a pivotal role in the antiviral immunity of pigs. Herein, based on the peptide binding motif of SLA-2*HB01, from an original SLA-2 allele, a series of functional T-cell epitopes derived from the dominant antigen VP1 of FMDV with high binding capacity to SLA-2 were identified. Two parallel peptides, Hu64 and As64, from the O and Asia I serotypes, respectively, were both crystallized with SLA-2*HB01. Compared to SLA-1 and SLA-3, the SLA-2 structures showed the flexibility of residues in the P4, P6, and P8 positions and in their potential interface with TCR. Notably, the peptides Hu64 and As64 adopted quite similar overall conformation when bound to SLA-2*HB01. Hu64 has two different conformations, a more stable 'chair' conformation and an unstable 'boat' conformation observed in the two molecules of one asymmetric unit, whereas only a single 'chair' conformation was observed for As64. Both Hu64 and As64 could induce similar dominant T-cell activities. Our interdisciplinary study establishes a basis for the in-depth interpretation of the peptide presentation of SLA-I, which can be used toward the development of universal vaccines.
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Affiliation(s)
- Lei Feng
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Yong-Yu Gao
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
- College of Animal Medicine, Jilin Agricultural University, Changchun 130118, China
| | - Mingwei Sun
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Zi-Bin Li
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
- Department of Microbiology and Immunology, College of Veterinary Medicine, China Agricultural University, Beijing 100094, China
| | - Qiang Zhang
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | - Jie Yang
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
- NHC Key Laboratory of Biosafety, Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Cui Qiao
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Hang Jin
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
| | - Hong-Sheng Feng
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
| | - Yu-Han Xian
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
| | - Jianxun Qi
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - George F. Gao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China
- NHC Key Laboratory of Biosafety, Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- Correspondence: (G.F.G.); (W.J.L.); (F.-S.G.)
| | - William J. Liu
- NHC Key Laboratory of Biosafety, Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- Correspondence: (G.F.G.); (W.J.L.); (F.-S.G.)
| | - Feng-Shan Gao
- Department of Bioengineering, College of Life and Health, Dalian University, Dalian 116622, China
- Correspondence: (G.F.G.); (W.J.L.); (F.-S.G.)
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7
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Dar HA, Almajhdi FN, Aziz S, Waheed Y. Immunoinformatics-Aided Analysis of RSV Fusion and Attachment Glycoproteins to Design a Potent Multi-Epitope Vaccine. Vaccines (Basel) 2022; 10:1381. [PMID: 36146460 PMCID: PMC9502547 DOI: 10.3390/vaccines10091381] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/16/2022] [Accepted: 08/20/2022] [Indexed: 11/16/2022] Open
Abstract
Respiratory syncytial virus (RSV) usually causes respiratory tract infections of upper airways in infants and young children. Despite recent medical advances, no approved vaccine is available to control RSV infections. Therefore, we conducted an immunoinformatics study to design and evaluate a potential multi-epitope vaccine against RSV. Sequence-based analyses of the glycoproteins F and G revealed a total of eight CD8 T-cell and three CD4 T-cell epitopes after considering antigenicity, binding affinity and other parameters. Molecular docking analysis confirmed that these T-cell epitopes developed strong structural associations with HLA allele(s). By integrating these prioritized epitopes with linkers and a cholera toxin-derived adjuvant, a multi-epitope vaccine was designed. The developed vaccine was found to be stable, non-allergenic, flexible and antigenic. Molecular docking analysis revealed a striking mean HADDOCK score (-143.3) of top-ranked vaccine-TLR cluster and a Gibbs free energy change (ΔG) value of -11.3 kcal mol-1. As per computational immune simulation results, the vaccine generated a high titer of antibodies (especially IgM) and effector T-cells. Also, codon optimization and in silico cloning ensured the increased expression of vaccine in Escherichia coli. Altogether, we anticipate that the multi-epitope vaccine reported in this study will stimulate humoral and cellular responses against RSV infection, subject to follow-up experimental validation.
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Affiliation(s)
- Hamza Arshad Dar
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Fahad Nasser Almajhdi
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Shahkaar Aziz
- Institute of Biotechnology and Genetic Engineering, The University of Agriculture, Peshawar 25000, Pakistan
| | - Yasir Waheed
- Office of Research, Innovation & Commercialization, Shaheed Zulfiqar Ali Bhutto Medical University (SZABMU), Islamabad 44000, Pakistan
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McShan AC, Devlin CA, Papadaki GF, Sun Y, Green AI, Morozov GI, Burslem GM, Procko E, Sgourakis NG. TAPBPR employs a ligand-independent docking mechanism to chaperone MR1 molecules. Nat Chem Biol 2022; 18:859-868. [PMID: 35725941 PMCID: PMC9703140 DOI: 10.1038/s41589-022-01049-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 04/28/2022] [Indexed: 11/08/2022]
Abstract
Chaperones tapasin and transporter associated with antigen processing (TAP)-binding protein related (TAPBPR) associate with the major histocompatibility complex (MHC)-related protein 1 (MR1) to promote trafficking and cell surface expression. However, the binding mechanism and ligand dependency of MR1/chaperone interactions remain incompletely characterized. Here in vitro, biochemical and computational studies reveal that, unlike MHC-I, TAPBPR recognizes MR1 in a ligand-independent manner owing to the absence of major structural changes in the MR1 α2-1 helix between empty and ligand-loaded molecules. Structural characterization using paramagnetic nuclear magnetic resonance experiments combined with restrained molecular dynamics simulations reveals that TAPBPR engages conserved surfaces on MR1 to induce similar adaptations to those seen in MHC-I/TAPBPR co-crystal structures. Finally, nuclear magnetic resonance relaxation dispersion experiments using 19F-labeled diclofenac show that TAPBPR can affect the exchange kinetics of noncovalent metabolites with the MR1 groove, serving as a catalyst. Our results support a role of chaperones in stabilizing nascent MR1 molecules to enable loading of endogenous or exogenous cargo.
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Affiliation(s)
- Andrew C McShan
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Christine A Devlin
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, IL, USA
| | - Georgia F Papadaki
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yi Sun
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Adam I Green
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Giora I Morozov
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - George M Burslem
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Cancer Biology and Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Erik Procko
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, IL, USA
| | - Nikolaos G Sgourakis
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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9
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Walters LC, Rozbesky D, Harlos K, Quastel M, Sun H, Springer S, Rambo RP, Mohammed F, Jones EY, McMichael AJ, Gillespie GM. Primary and secondary functions of HLA-E are determined by stability and conformation of the peptide-bound complexes. Cell Rep 2022; 39:110959. [PMID: 35705051 PMCID: PMC9380258 DOI: 10.1016/j.celrep.2022.110959] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 02/11/2022] [Accepted: 05/23/2022] [Indexed: 11/19/2022] Open
Abstract
MHC-E regulates NK cells by displaying MHC class Ia signal peptides (VL9) to NKG2A:CD94 receptors. MHC-E can also present sequence-diverse, lower-affinity, pathogen-derived peptides to T cell receptors (TCRs) on CD8+ T cells. To understand these affinity differences, human MHC-E (HLA-E)-VL9 versus pathogen-derived peptide structures are compared. Small-angle X-ray scatter (SAXS) measures biophysical parameters in solution, allowing comparison with crystal structures. For HLA-E-VL9, there is concordance between SAXS and crystal parameters. In contrast, HLA-E-bound pathogen-derived peptides produce larger SAXS dimensions that reduce to their crystallographic dimensions only when excess peptide is supplied. Further crystallographic analysis demonstrates three amino acids, exclusive to MHC-E, that not only position VL9 close to the α2 helix, but also allow non-VL9 peptide binding with re-configuration of a key TCR-interacting α2 region. Thus, non-VL9-bound peptides introduce an alternative peptide-binding motif and surface recognition landscape, providing a likely basis for VL9- and non-VL9-HLA-E immune discrimination.
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Affiliation(s)
- Lucy C Walters
- Nuffield Department of Medicine Research Building, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Daniel Rozbesky
- Department of Cell Biology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Karl Harlos
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Max Quastel
- Nuffield Department of Medicine Research Building, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Hong Sun
- Nuffield Department of Medicine Research Building, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK; Department of Laboratory Medicine, The First Affiliated Hospital, China Medical University, Shenyang, China
| | - Sebastian Springer
- Department of Life Sciences and Chemistry, Jacobs University Bremen, Bremen, Germany
| | - Robert P Rambo
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Fiyaz Mohammed
- Institute of Immunology and Immunotherapy, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Andrew J McMichael
- Nuffield Department of Medicine Research Building, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK.
| | - Geraldine M Gillespie
- Nuffield Department of Medicine Research Building, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK.
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10
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Perez MAS, Cuendet MA, Röhrig UF, Michielin O, Zoete V. Structural Prediction of Peptide-MHC Binding Modes. Methods Mol Biol 2022; 2405:245-282. [PMID: 35298818 DOI: 10.1007/978-1-0716-1855-4_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The immune system is constantly protecting its host from the invasion of pathogens and the development of cancer cells. The specific CD8+ T-cell immune response against virus-infected cells and tumor cells is based on the T-cell receptor recognition of antigenic peptides bound to class I major histocompatibility complexes (MHC) at the surface of antigen presenting cells. Consequently, the peptide binding specificities of the highly polymorphic MHC have important implications for the design of vaccines, for the treatment of autoimmune diseases, and for personalized cancer immunotherapy. Evidence-based machine-learning approaches have been successfully used for the prediction of peptide binders and are currently being developed for the prediction of peptide immunogenicity. However, understanding and modeling the structural details of peptide/MHC binding is crucial for a better understanding of the molecular mechanisms triggering the immunological processes, estimating peptide/MHC affinity using universal physics-based approaches, and driving the design of novel peptide ligands. Unfortunately, due to the large diversity of MHC allotypes and possible peptides, the growing number of 3D structures of peptide/MHC (pMHC) complexes in the Protein Data Bank only covers a small fraction of the possibilities. Consequently, there is a growing need for rapid and efficient approaches to predict 3D structures of pMHC complexes. Here, we review the key characteristics of the 3D structure of pMHC complexes before listing databases and other sources of information on pMHC structures and MHC specificities. Finally, we discuss some of the most prominent pMHC docking software.
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Affiliation(s)
- Marta A S Perez
- Computer-aided Molecular Engineering Group, Department of Oncology UNIL-CHUV, Lausanne University, Lausanne, Switzerland
- Ludwig Institute for Cancer Research, Lausanne, Switzerland
- Molecular Modelling Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Michel A Cuendet
- Molecular Modelling Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
- Oncology Department, Centre Hospitalier Universitaire Vaudois (CHUV), Precision Oncology Center, Lausanne, Switzerland
| | - Ute F Röhrig
- Molecular Modelling Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Olivier Michielin
- Molecular Modelling Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.
- Oncology Department, Centre Hospitalier Universitaire Vaudois (CHUV), Precision Oncology Center, Lausanne, Switzerland.
| | - Vincent Zoete
- Computer-aided Molecular Engineering Group, Department of Oncology UNIL-CHUV, Lausanne University, Lausanne, Switzerland.
- Ludwig Institute for Cancer Research, Lausanne, Switzerland.
- Molecular Modelling Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.
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11
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McShan AC, Devlin CA, Morozov GI, Overall SA, Moschidi D, Akella N, Procko E, Sgourakis NG. TAPBPR promotes antigen loading on MHC-I molecules using a peptide trap. Nat Commun 2021; 12:3174. [PMID: 34039964 PMCID: PMC8154891 DOI: 10.1038/s41467-021-23225-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 04/16/2021] [Indexed: 11/08/2022] Open
Abstract
Chaperones Tapasin and TAP-binding protein related (TAPBPR) perform the important functions of stabilizing nascent MHC-I molecules (chaperoning) and selecting high-affinity peptides in the MHC-I groove (editing). While X-ray and cryo-EM snapshots of MHC-I in complex with TAPBPR and Tapasin, respectively, have provided important insights into the peptide-deficient MHC-I groove structure, the molecular mechanism through which these chaperones influence the selection of specific amino acid sequences remains incompletely characterized. Based on structural and functional data, a loop sequence of variable lengths has been proposed to stabilize empty MHC-I molecules through direct interactions with the floor of the groove. Using deep mutagenesis on two complementary expression systems, we find that important residues for the Tapasin/TAPBPR chaperoning activity are located on a large scaffolding surface, excluding the loop. Conversely, loop mutations influence TAPBPR interactions with properly conformed MHC-I molecules, relevant for peptide editing. Detailed biophysical characterization by solution NMR, ITC and FP-based assays shows that the loop hovers above the MHC-I groove to promote the capture of incoming peptides. Our results suggest that the longer loop of TAPBPR lowers the affinity requirements for peptide selection to facilitate peptide loading under conditions and subcellular compartments of reduced ligand concentration, and to prevent disassembly of high-affinity peptide-MHC-I complexes that are transiently interrogated by TAPBPR during editing.
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Affiliation(s)
- Andrew C McShan
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Christine A Devlin
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, IL, USA
| | - Giora I Morozov
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Sarah A Overall
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Danai Moschidi
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Neha Akella
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, IL, USA
| | - Erik Procko
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, IL, USA.
| | - Nikolaos G Sgourakis
- Center for Computational and Genomic Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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12
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Finton KAK, Brusniak MY, Jones LA, Lin C, Fioré-Gartland AJ, Brock C, Gafken PR, Strong RK. ARTEMIS: A Novel Mass-Spec Platform for HLA-Restricted Self and Disease-Associated Peptide Discovery. Front Immunol 2021; 12:658372. [PMID: 33986749 PMCID: PMC8111693 DOI: 10.3389/fimmu.2021.658372] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 03/30/2021] [Indexed: 11/25/2022] Open
Abstract
Conventional immunoprecipitation/mass spectroscopy identification of HLA-restricted peptides remains the purview of specializing laboratories, due to the complexity of the methodology, and requires computational post-analysis to assign peptides to individual alleles when using pan-HLA antibodies. We have addressed these limitations with ARTEMIS: a simple, robust, and flexible platform for peptide discovery across ligandomes, optionally including specific proteins-of-interest, that combines novel, secreted HLA-I discovery reagents spanning multiple alleles, optimized lentiviral transduction, and streamlined affinity-tag purification to improve upon conventional methods. This platform fills a middle ground between existing techniques: sensitive and adaptable, but easy and affordable enough to be widely employed by general laboratories. We used ARTEMIS to catalog allele-specific ligandomes from HEK293 cells for seven classical HLA alleles and compared results across replicates, against computational predictions, and against high-quality conventional datasets. We also applied ARTEMIS to identify potentially useful, novel HLA-restricted peptide targets from oncovirus oncoproteins and tumor-associated antigens.
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Affiliation(s)
- Kathryn A K Finton
- Division of Basic Science, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Mi-Youn Brusniak
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Lisa A Jones
- Proteomics Shared Resource, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Chenwei Lin
- Proteomics Shared Resource, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Andrew J Fioré-Gartland
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Chance Brock
- Division of Basic Science, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Philip R Gafken
- Proteomics Shared Resource, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
| | - Roland K Strong
- Division of Basic Science, Fred Hutchinson Cancer Research Center, Seattle, WA, United States
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13
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Szeto C, Chatzileontiadou DS, Nguyen AT, Sloane H, Lobos CA, Jayasinghe D, Halim H, Smith C, Riboldi-Tunnicliffe A, Grant EJ, Gras S. The presentation of SARS-CoV-2 peptides by the common HLA-A ∗02:01 molecule. iScience 2021; 24:102096. [PMID: 33521593 PMCID: PMC7825995 DOI: 10.1016/j.isci.2021.102096] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/17/2020] [Accepted: 01/15/2021] [Indexed: 12/27/2022] Open
Abstract
CD8+ T cells are crucial for anti-viral immunity; however, understanding T cell responses requires the identification of epitopes presented by human leukocyte antigens (HLA). To date, few SARS-CoV-2-specific CD8+ T cell epitopes have been described. Internal viral proteins are typically more conserved than surface proteins and are often the target of CD8+ T cells. Therefore, we have characterized eight peptides derived from the internal SARS-CoV-2 nucleocapsid protein predicted to bind HLA-A∗02:01, the most common HLA molecule in the global population. We determined not all peptides could form a complex with HLA-A∗02:01, and the six crystal structures determined revealed that some peptides adopted a mobile conformation. We therefore provide a molecular understanding of SARS-CoV-2 CD8+ T cell epitopes. Furthermore, we show that there is limited pre-existing CD8+ T cell response toward these epitopes in unexposed individuals. Together, these data show that SARS-CoV-2 nucleocapsid might not contain potent epitopes restricted to HLA-A∗02:01. HLA-A∗02:01 individuals have limited pre-existing immunity to SARS-CoV-2 nucleocapsid High-resolution crystal structures of HLA-A∗02:01 presenting SARS-CoV-2 peptides Structural analysis of pHLA shows stability influences peptide immunogenicity
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Affiliation(s)
- Christopher Szeto
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
| | - Demetra S.M. Chatzileontiadou
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
| | - Andrea T. Nguyen
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
| | - Hannah Sloane
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
| | - Christian A. Lobos
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
| | - Dhilshan Jayasinghe
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
| | - Hanim Halim
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Corey Smith
- QIMR Centre for Immunotherapy and Vaccine Development and Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia
| | | | - Emma J. Grant
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
- Corresponding author
| | - Stephanie Gras
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
- Australian Research Council Centre of Excellence for Advanced Molecular Imaging, Monash University, Clayton, VIC 3800, Australia
- Corresponding author
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14
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Tedeschi V, Paldino G, Paladini F, Mattorre B, Tuosto L, Sorrentino R, Fiorillo MT. The Impact of the 'Mis-Peptidome' on HLA Class I-Mediated Diseases: Contribution of ERAP1 and ERAP2 and Effects on the Immune Response. Int J Mol Sci 2020; 21:ijms21249608. [PMID: 33348540 PMCID: PMC7765998 DOI: 10.3390/ijms21249608] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/09/2020] [Accepted: 12/14/2020] [Indexed: 01/08/2023] Open
Abstract
The strong association with the Major Histocompatibility Complex (MHC) class I genes represents a shared trait for a group of autoimmune/autoinflammatory disorders having in common immunopathogenetic basis as well as clinical features. Accordingly, the main risk factors for Ankylosing Spondylitis (AS), prototype of the Spondyloarthropathies (SpA), the Behçet's disease (BD), the Psoriasis (Ps) and the Birdshot Chorioretinopathy (BSCR) are HLA-B*27, HLA-B*51, HLA-C*06:02 and HLA-A*29:02, respectively. Despite the strength of the association, the HLA pathogenetic role in these diseases is far from being thoroughly understood. Furthermore, Genome-Wide Association Studies (GWAS) have highlighted other important susceptibility factors such as Endoplasmic Reticulum Aminopeptidase (ERAP) 1 and, less frequently, ERAP2 that refine the peptidome presented by HLA class I molecules to CD8+ T cells. Mass spectrometry analysis provided considerable knowledge of HLA-B*27, HLA-B*51, HLA-C*06:02 and HLA-A*29:02 immunopeptidome. However, the combined effect of several ERAP1 and ERAP2 allelic variants could generate an altered pool of peptides accounting for the "mis-immunopeptidome" that ranges from suboptimal to pathogenetic/harmful peptides able to induce non-canonical or autoreactive CD8+ T responses, activation of NK cells and/or garbling the classical functions of the HLA class I molecules. This review will focus on this class of epitopes as possible elicitors of atypical/harmful immune responses which can contribute to the pathogenesis of chronic inflammatory diseases.
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Affiliation(s)
- Valentina Tedeschi
- Department of Biology and Biotechnology ‘Charles Darwin’, Sapienza University, 00185 Rome, Italy; (G.P.); (F.P.); (B.M.); (L.T.); (R.S.); (M.T.F.)
- Correspondence:
| | - Giorgia Paldino
- Department of Biology and Biotechnology ‘Charles Darwin’, Sapienza University, 00185 Rome, Italy; (G.P.); (F.P.); (B.M.); (L.T.); (R.S.); (M.T.F.)
| | - Fabiana Paladini
- Department of Biology and Biotechnology ‘Charles Darwin’, Sapienza University, 00185 Rome, Italy; (G.P.); (F.P.); (B.M.); (L.T.); (R.S.); (M.T.F.)
| | - Benedetta Mattorre
- Department of Biology and Biotechnology ‘Charles Darwin’, Sapienza University, 00185 Rome, Italy; (G.P.); (F.P.); (B.M.); (L.T.); (R.S.); (M.T.F.)
| | - Loretta Tuosto
- Department of Biology and Biotechnology ‘Charles Darwin’, Sapienza University, 00185 Rome, Italy; (G.P.); (F.P.); (B.M.); (L.T.); (R.S.); (M.T.F.)
- Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, 00185 Rome, Italy
| | - Rosa Sorrentino
- Department of Biology and Biotechnology ‘Charles Darwin’, Sapienza University, 00185 Rome, Italy; (G.P.); (F.P.); (B.M.); (L.T.); (R.S.); (M.T.F.)
| | - Maria Teresa Fiorillo
- Department of Biology and Biotechnology ‘Charles Darwin’, Sapienza University, 00185 Rome, Italy; (G.P.); (F.P.); (B.M.); (L.T.); (R.S.); (M.T.F.)
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15
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Singh NK, Alonso JA, Harris DT, Anderson SD, Ma J, Hellman LM, Rosenberg AM, Kolawole EM, Evavold BD, Kranz DM, Baker BM. An Engineered T Cell Receptor Variant Realizes the Limits of Functional Binding Modes. Biochemistry 2020; 59:4163-4175. [PMID: 33074657 DOI: 10.1021/acs.biochem.0c00689] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
T cell receptors (TCRs) orchestrate cellular immunity by recognizing peptides presented by a range of major histocompatibility complex (MHC) proteins. Naturally occurring TCRs bind the composite peptide/MHC surface, recognizing peptides that are structurally and chemically compatible with the TCR binding site. Here we describe a molecularly evolved TCR variant that binds the human class I MHC protein HLA-A2 independent of the bound peptide, achieved by a drastic perturbation of the TCR binding geometry that places the molecule far from the peptide binding groove. This unique geometry is unsupportive of normal T cell signaling. A substantial divergence between affinity measurements in solution and in two dimensions between proximal cell membranes leads us to attribute the lack of signaling to steric hindrance that limits binding in the confines of a cell-cell interface. Our results provide an example of how receptor binding geometry can impact T cell function and provide further support for the view that germline-encoded residues in TCR binding loops evolved to drive productive TCR recognition and signaling.
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Affiliation(s)
- Nishant K Singh
- Department of Chemistry and Biochemistry and Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jesus A Alonso
- Department of Chemistry and Biochemistry and Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Daniel T Harris
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, Illinois 61801, United States
| | - Scott D Anderson
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, Illinois 61801, United States
| | - Jiaqi Ma
- Department of Chemistry and Biochemistry and Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Lance M Hellman
- Department of Chemistry and Biochemistry and Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Aaron M Rosenberg
- Department of Chemistry and Biochemistry and Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Elizabeth M Kolawole
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, Utah 84112, United States
| | - Brian D Evavold
- Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, Utah 84112, United States
| | - David M Kranz
- Department of Biochemistry and Cancer Center at Illinois, University of Illinois, Urbana, Illinois 61801, United States
| | - Brian M Baker
- Department of Chemistry and Biochemistry and Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana 46556, United States
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16
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Marchan J. Conserved HLA binding peptides from five non-structural proteins of SARS-CoV-2-An in silico glance. Hum Immunol 2020; 81:588-595. [PMID: 32888767 PMCID: PMC7425717 DOI: 10.1016/j.humimm.2020.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/08/2020] [Accepted: 08/10/2020] [Indexed: 01/08/2023]
Abstract
Coronavirus Disease 2019 (COVID-19) is a dangerous global threat that has no clinically approved treatment yet. Bioinformatics represent an outstanding approach to reveal key immunogenic regions in viral proteins. Here, five severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) non-structural proteins (NSPs) (NSP7, NSP8, NSP9, NSP12, and NSP13) were screened to identify potential human leukocyte antigen (HLA) binding peptides. These peptides showed robust viral antigenicity, immunogenicity, and a marked interaction with HLA alleles. Interestingly, several peptides showed affinity by HLA class I (HLA-I) alleles that commonly activates to natural killer (NK) cells. Notably, HLA biding peptides are conserved among SARS-CoV-2, severe acute respiratory syndrome coronavirus (SARS-CoV), and Middle Eastern respiratory syndrome coronavirus (MERS-CoV). Interestingly, HLA-I and HLA class II (HLA-II) binding peptides induced humoral and cell-mediated responses after in silico vaccination. These results may open further in vitro and in vivo investigations to develop novel therapeutic strategies against coronaviral infections.
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Affiliation(s)
- Jose Marchan
- Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Científicas, Venezuela.
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17
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Overall SA, Toor JS, Hao S, Yarmarkovich M, Sara M O'Rourke, Morozov GI, Nguyen S, Japp AS, Gonzalez N, Moschidi D, Betts MR, Maris JM, Smibert P, Sgourakis NG. High throughput pMHC-I tetramer library production using chaperone-mediated peptide exchange. Nat Commun 2020; 11:1909. [PMID: 32312993 PMCID: PMC7170893 DOI: 10.1038/s41467-020-15710-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 03/23/2020] [Indexed: 12/31/2022] Open
Abstract
Peptide exchange technologies are essential for the generation of pMHC-multimer libraries used to probe diverse, polyclonal TCR repertoires in various settings. Here, using the molecular chaperone TAPBPR, we develop a robust method for the capture of stable, empty MHC-I molecules comprising murine H2 and human HLA alleles, which can be readily tetramerized and loaded with peptides of choice in a high-throughput manner. Alternatively, catalytic amounts of TAPBPR can be used to exchange placeholder peptides with high affinity peptides of interest. Using the same system, we describe high throughput assays to validate binding of multiple candidate peptides on empty MHC-I/TAPBPR complexes. Combined with tetramer-barcoding via a multi-modal cellular indexing technology, ECCITE-seq, our approach allows a combined analysis of TCR repertoires and other T cell transcription profiles together with their cognate antigen specificities in a single experiment. The new approach allows TCR/pMHC interactions to be interrogated easily at large scale.
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Affiliation(s)
- Sarah A Overall
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High St., Santa Cruz, CA, 95064, USA
| | - Jugmohit S Toor
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High St., Santa Cruz, CA, 95064, USA
| | - Stephanie Hao
- Technology Innovation Lab, New York Genome Center, 101 6th Ave, New York, NY, 10013, USA
| | - Mark Yarmarkovich
- Division of Oncology, Center for Childhood Cancer Research, Children's Hospital of Philadelphia and Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - Sara M O'Rourke
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High St., Santa Cruz, CA, 95064, USA
| | - Giora I Morozov
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High St., Santa Cruz, CA, 95064, USA
| | - Son Nguyen
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - Alberto Sada Japp
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - Nicolas Gonzalez
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High St., Santa Cruz, CA, 95064, USA
| | - Danai Moschidi
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High St., Santa Cruz, CA, 95064, USA
| | - Michael R Betts
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - John M Maris
- Division of Oncology, Center for Childhood Cancer Research, Children's Hospital of Philadelphia and Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - Peter Smibert
- Technology Innovation Lab, New York Genome Center, 101 6th Ave, New York, NY, 10013, USA
| | - Nikolaos G Sgourakis
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High St., Santa Cruz, CA, 95064, USA.
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18
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Singh NK, Abualrous ET, Ayres CM, Noé F, Gowthaman R, Pierce BG, Baker BM. Geometrical characterization of T cell receptor binding modes reveals class-specific binding to maximize access to antigen. Proteins 2020; 88:503-513. [PMID: 31589793 PMCID: PMC6982585 DOI: 10.1002/prot.25829] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 08/08/2019] [Accepted: 09/17/2019] [Indexed: 11/11/2022]
Abstract
Recognition of antigenic peptides bound to major histocompatibility complex (MHC) proteins by αβ T cell receptors (TCRs) is a hallmark of T cell mediated immunity. Recent data suggest that variations in TCR binding geometry may influence T cell signaling, which could help explain outliers in relationships between physical parameters such as TCR-pMHC binding affinity and T cell function. Traditionally, TCR binding geometry has been described with simple descriptors such as the crossing angle, which quantifies what has become known as the TCR's diagonal binding mode. However, these descriptors often fail to reveal distinctions in binding geometry that are apparent through visual inspection. To provide a better framework for relating TCR structure to T cell function, we developed a comprehensive system for quantifying the geometries of how TCRs bind peptide/MHC complexes. We show that our system can discern differences not clearly revealed by more common methods. As an example of its potential to impact biology, we used it to reveal differences in how TCRs bind class I and class II peptide/MHC complexes, which we show allow the TCR to maximize access to and "read out" the peptide antigen. We anticipate our system will be of use in not only exploring these and other details of TCR-peptide/MHC binding interactions, but also addressing questions about how TCR binding geometry relates to T cell function, as well as modeling structural properties of class I and class II TCR-peptide/MHC complexes from sequence information. The system is available at https://tcr3d.ibbr.umd.edu/tcr_com or for download as a script.
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MESH Headings
- Binding Sites
- Crystallography, X-Ray
- Histocompatibility Antigens Class I/chemistry
- Histocompatibility Antigens Class I/immunology
- Histocompatibility Antigens Class I/metabolism
- Histocompatibility Antigens Class II/chemistry
- Histocompatibility Antigens Class II/immunology
- Histocompatibility Antigens Class II/metabolism
- Humans
- Models, Molecular
- Principal Component Analysis
- Protein Binding
- Protein Conformation, alpha-Helical
- Protein Conformation, beta-Strand
- Protein Interaction Domains and Motifs
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- T-Lymphocytes/chemistry
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
- Thermodynamics
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Affiliation(s)
- Nishant K. Singh
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States
- Harper Cancer Research Institute, University of Notre Dame, South Bend, IN, United States
| | - Esam T. Abualrous
- Molecular Biology Group, Institute for Mathematics, Freie Universität Berlin, Berlin, Germany
| | - Cory M. Ayres
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States
- Harper Cancer Research Institute, University of Notre Dame, South Bend, IN, United States
| | - Frank Noé
- Molecular Biology Group, Institute for Mathematics, Freie Universität Berlin, Berlin, Germany
| | - Ragul Gowthaman
- University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD, United States
| | - Brian G. Pierce
- University of Maryland Institute for Bioscience and Biotechnology Research, Rockville, MD, United States
| | - Brian M. Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States
- Harper Cancer Research Institute, University of Notre Dame, South Bend, IN, United States
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19
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Molecular determinants of chaperone interactions on MHC-I for folding and antigen repertoire selection. Proc Natl Acad Sci U S A 2019; 116:25602-25613. [PMID: 31796585 PMCID: PMC6926029 DOI: 10.1073/pnas.1915562116] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The interplay between a highly polymorphic set of MHC-I alleles and molecular chaperones shapes the repertoire of peptide antigens displayed on the cell surface for T cell surveillance. Here, we demonstrate that the molecular chaperone TAP-binding protein related (TAPBPR) associates with a broad range of partially folded MHC-I species inside the cell. Bimolecular fluorescence complementation and deep mutational scanning reveal that TAPBPR recognition is polarized toward the α2 domain of the peptide-binding groove, and depends on the formation of a conserved MHC-I disulfide epitope in the α2 domain. Conversely, thermodynamic measurements of TAPBPR binding for a representative set of properly conformed, peptide-loaded molecules suggest a narrower MHC-I specificity range. Using solution NMR, we find that the extent of dynamics at "hotspot" surfaces confers TAPBPR recognition of a sparsely populated MHC-I state attained through a global conformational change. Consistently, restriction of MHC-I groove plasticity through the introduction of a disulfide bond between the α1/α2 helices abrogates TAPBPR binding, both in solution and on a cellular membrane, while intracellular binding is tolerant of many destabilizing MHC-I substitutions. Our data support parallel TAPBPR functions of 1) chaperoning unstable MHC-I molecules with broad allele-specificity at early stages of their folding process, and 2) editing the peptide cargo of properly conformed MHC-I molecules en route to the surface, which demonstrates a narrower specificity. Our results suggest that TAPBPR exploits localized structural adaptations, both near and distant to the peptide-binding groove, to selectively recognize discrete conformational states sampled by MHC-I alleles, toward editing the repertoire of displayed antigens.
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20
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Riley TP, Keller GLJ, Smith AR, Davancaze LM, Arbuiso AG, Devlin JR, Baker BM. Structure Based Prediction of Neoantigen Immunogenicity. Front Immunol 2019; 10:2047. [PMID: 31555277 PMCID: PMC6724579 DOI: 10.3389/fimmu.2019.02047] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 08/13/2019] [Indexed: 12/30/2022] Open
Abstract
The development of immunological therapies that incorporate peptide antigens presented to T cells by MHC proteins is a long sought-after goal, particularly for cancer, where mutated neoantigens are being explored as personalized cancer vaccines. Although neoantigens can be identified through sequencing, bioinformatics and mass spectrometry, identifying those which are immunogenic and able to promote tumor rejection remains a significant challenge. Here we examined the potential of high-resolution structural modeling followed by energetic scoring of structural features for predicting neoantigen immunogenicity. After developing a strategy to rapidly and accurately model nonameric peptides bound to the common class I MHC protein HLA-A2, we trained a neural network on structural features that influence T cell receptor (TCR) and peptide binding energies. The resulting structurally-parameterized neural network outperformed methods that do not incorporate explicit structural or energetic properties in predicting CD8+ T cell responses of HLA-A2 presented nonameric peptides, while also providing insight into the underlying structural and biophysical mechanisms governing immunogenicity. Our proof-of-concept study demonstrates the potential for structure-based immunogenicity predictions in the development of personalized peptide-based vaccines.
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Affiliation(s)
| | | | | | | | | | | | - Brian M. Baker
- Department of Chemistry and Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN, United States
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21
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Madura F, Rizkallah PJ, Legut M, Holland CJ, Fuller A, Bulek A, Schauenburg AJ, Trimby A, Hopkins JR, Wells SA, Godkin A, Miles JJ, Sami M, Li Y, Liddy N, Jakobsen BK, Loveridge EJ, Cole DK, Sewell AK. TCR-induced alteration of primary MHC peptide anchor residue. Eur J Immunol 2019; 49:1052-1066. [PMID: 31091334 PMCID: PMC6618058 DOI: 10.1002/eji.201948085] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 03/21/2019] [Accepted: 05/14/2019] [Indexed: 12/12/2022]
Abstract
The HLA-A*02:01-restricted decapeptide EAAGIGILTV, derived from melanoma antigen recognized by T-cells-1 (MART-1) protein, represents one of the best-studied tumor associated T-cell epitopes, but clinical results targeting this peptide have been disappointing. This limitation may reflect the dominance of the nonapeptide, AAGIGILTV, at the melanoma cell surface. The decapeptide and nonapeptide are presented in distinct conformations by HLA-A*02:01 and TCRs from clinically relevant T-cell clones recognize the nonapeptide poorly. Here, we studied the MEL5 TCR that potently recognizes the nonapeptide. The structure of the MEL5-HLA-A*02:01-AAGIGILTV complex revealed an induced fit mechanism of antigen recognition involving altered peptide-MHC anchoring. This "flexing" at the TCR-peptide-MHC interface to accommodate the peptide antigen explains previously observed incongruences in this well-studied system and has important implications for future therapeutic approaches. Finally, this study expands upon the mechanisms by which molecular plasticity can influence antigen recognition by T cells.
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Affiliation(s)
| | | | | | | | - Anna Fuller
- School of MedicineCardiff UniversityCardiffUK
| | - Anna Bulek
- School of MedicineCardiff UniversityCardiffUK
| | | | | | | | | | | | - John J. Miles
- School of MedicineCardiff UniversityCardiffUK
- Centre for Biodiscovery and Molecular Development of TherapeuticsAustralian Institute of Tropical Health and MedicineJames Cook UniversityCairnsQueenslandAustralia
| | | | - Yi Li
- Immunocore Ltd.AbingdonUK
| | | | | | - E. Joel Loveridge
- School of ChemistryCardiff UniversityCardiffUK
- Department of ChemistrySwansea UniversitySwanseaUK
| | - David K. Cole
- School of MedicineCardiff UniversityCardiffUK
- Immunocore Ltd.AbingdonUK
| | - Andrew K. Sewell
- School of MedicineCardiff UniversityCardiffUK
- Systems Immunity Research InstituteCardiff UniversityCardiffUK
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22
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Tedeschi V, Alba J, Paladini F, Paroli M, Cauli A, Mathieu A, Sorrentino R, D'Abramo M, Fiorillo MT. Unusual Placement of an EBV Epitope into the Groove of the Ankylosing Spondylitis-Associated HLA-B27 Allele Allows CD8+ T Cell Activation. Cells 2019; 8:cells8060572. [PMID: 31212633 PMCID: PMC6627668 DOI: 10.3390/cells8060572] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/06/2019] [Accepted: 06/08/2019] [Indexed: 02/02/2023] Open
Abstract
The human leukocyte antigen HLA-B27 is a strong risk factor for Ankylosing Spondylitis (AS), an immune-mediated disorder affecting axial skeleton and sacroiliac joints. Additionally, evidence exists sustaining a strong protective role for HLA-B27 in viral infections. These two aspects could stem from common molecular mechanisms. Recently, we have found that the HLA-B*2705 presents an EBV epitope (pEBNA3A-RPPIFIRRL), lacking the canonical B27 binding motif but known as immunodominant in the HLA-B7 context of presentation. Notably, 69% of B*2705 carriers, mostly patients with AS, possess B*2705-restricted, pEBNA3A-specific CD8+ T cells. Contrarily, the non-AS-associated B*2709 allele, distinguished from the B*2705 by the single His116Asp polymorphism, is unable to display this peptide and, accordingly, B*2709 healthy subjects do not unleash specific T cell responses. Herein, we investigated whether the reactivity towards pEBNA3A could be a side effect of the recognition of the natural longer peptide (pKEBNA3A) having the classical B27 consensus (KRPPIFIRRL). The stimulation of PBMC from B*2705 positive patients with AS in parallel with both pEBNA3A and pKEBNA3A did not allow to reach an unambiguous conclusion since the differences in the magnitude of the response measured as percentage of IFNγ-producing CD8+ T cells were not statistically significant. Interestingly, computational analysis suggested a structural shift of pEBNA3A as well as of pKEBNA3A into the B27 grooves, leaving the A pocket partially unfilled. To our knowledge this is the first report of a viral peptide: HLA-B27 complex recognized by TCRs in spite of a partially empty groove. This implies a rethinking of the actual B27 immunopeptidome crucial for viral immune-surveillance and autoimmunity.
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Affiliation(s)
- Valentina Tedeschi
- Department of Biology and Biotechnology 'Charles Darwin', Sapienza University of Rome, 00185 Rome, Italy.
| | - Josephine Alba
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy.
| | - Fabiana Paladini
- Department of Biology and Biotechnology 'Charles Darwin', Sapienza University of Rome, 00185 Rome, Italy.
| | - Marino Paroli
- Division of Clinical Immunology and Rheumatology, Department of Biotechnology and Medical Surgical Sciences, Sapienza University of Rome, 00185 Rome, Italy.
| | - Alberto Cauli
- Rheumatology Unit, Department of Medical Sciences and Public Health, University and AOU of Cagliari, Monserrato, 09042 Cagliari, Italy.
| | - Alessandro Mathieu
- Rheumatology Unit, Department of Medical Sciences and Public Health, University and AOU of Cagliari, Monserrato, 09042 Cagliari, Italy.
| | - Rosa Sorrentino
- Department of Biology and Biotechnology 'Charles Darwin', Sapienza University of Rome, 00185 Rome, Italy.
| | - Marco D'Abramo
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy.
| | - Maria Teresa Fiorillo
- Department of Biology and Biotechnology 'Charles Darwin', Sapienza University of Rome, 00185 Rome, Italy.
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23
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Ayres CM, Abualrous ET, Bailey A, Abraham C, Hellman LM, Corcelli SA, Noé F, Elliott T, Baker BM. Dynamically Driven Allostery in MHC Proteins: Peptide-Dependent Tuning of Class I MHC Global Flexibility. Front Immunol 2019; 10:966. [PMID: 31130956 PMCID: PMC6509175 DOI: 10.3389/fimmu.2019.00966] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 04/15/2019] [Indexed: 11/21/2022] Open
Abstract
T cell receptor (TCR) recognition of antigenic peptides bound and presented by class I major histocompatibility complex (MHC) proteins underlies the cytotoxic immune response to diseased cells. Crystallographic structures of TCR-peptide/MHC complexes have demonstrated how TCRs simultaneously interact with both the peptide and the MHC protein. However, it is increasingly recognized that, beyond serving as a static platform for peptide presentation, the physical properties of class I MHC proteins are tuned by different peptides in ways that are not always structurally visible. These include MHC protein motions, or dynamics, which are believed to influence interactions with a variety of MHC-binding proteins, including not only TCRs, but other activating and inhibitory receptors as well as components of the peptide loading machinery. Here, we investigated the mechanisms by which peptides tune the dynamics of the common class I MHC protein HLA-A2. By examining more than 50 lengthy molecular dynamics simulations of HLA-A2 presenting different peptides, we identified regions susceptible to dynamic tuning, including regions in the peptide binding domain as well as the distal α3 domain. Further analyses of the simulations illuminated mechanisms by which the influences of different peptides are communicated throughout the protein, and involve regions of the peptide binding groove, the β2-microglobulin subunit, and the α3 domain. Overall, our results demonstrate that the class I MHC protein is a highly tunable peptide sensor whose physical properties vary considerably with bound peptide. Our data provides insight into the underlying principles and suggest a role for dynamically driven allostery in the immunological function of MHC proteins.
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Affiliation(s)
- Cory M Ayres
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States.,Harper Cancer Research Institute, University of Notre Dame, South Bend, IN, United States
| | - Esam T Abualrous
- Computational Molecular Biology Group, Institute for Mathematics, Freie Universität Berlin, Berlin, Germany
| | - Alistair Bailey
- Institute for Life Sciences and Centre for Cancer Immunology, University of Southampton, Southampton, United Kingdom
| | - Christian Abraham
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States.,Harper Cancer Research Institute, University of Notre Dame, South Bend, IN, United States
| | - Lance M Hellman
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States.,Harper Cancer Research Institute, University of Notre Dame, South Bend, IN, United States
| | - Steven A Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States
| | - Frank Noé
- Computational Molecular Biology Group, Institute for Mathematics, Freie Universität Berlin, Berlin, Germany
| | - Tim Elliott
- Institute for Life Sciences and Centre for Cancer Immunology, University of Southampton, Southampton, United Kingdom
| | - Brian M Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States.,Harper Cancer Research Institute, University of Notre Dame, South Bend, IN, United States
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24
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Bai X, Wang D, Liu Y, Xiao L, Liang Y, Yang Y, Zhang J, Lin M, Wu X. Novel epitopes identified from Mycobacterium tuberculosis antigen Rv2629induces cytotoxic T lymphocyte response. Immunol Lett 2018; 203:21-28. [PMID: 29908955 DOI: 10.1016/j.imlet.2018.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 05/11/2018] [Accepted: 06/13/2018] [Indexed: 02/08/2023]
Abstract
There is an urgent need for a more effective vaccine against tuberculosis (TB). Cytotoxic T lymphocytes (CTLs) play a critical role in combating Mycobacterium tuberculosis (M.tb). The identification of novel CTL epitopes is essential for the design of peptide-based vaccines. In this study, we predicted CTL epitope peptides of M.tb antigen Rv2629 restricted by HLA-A2, using bioinformatics methods. The affinity and stability of binding of these peptides with HLA-A2 molecules were detected by flow cytometry. Their ability to induce CTLs generation was determined in peripheral blood mononuclear cells (PBMCs) from healthy uninfected subjects, Latent tuberculosis infection (LTBI) subjects, and TB patients ex vivo. The cytotoxic activity induced by the epitope peptides was tested by lactate dehydrogenase (LDH) release assay. Finally, we found four novel CTL epitope peptides, Rv2629-p190-2L, Rv2629-p190-1Y2L, Rv2629-p274, and Rv2629-p315, which had high-affinity and stability of binding with T2 cells. Their ability of inducing CTLs was highest in PBMCs from TB patients (P < 0.05). In addition, these peptides could induce the CTLs to generate specific cytotoxic activity. They showed higher immunogenicity in TB patients and had the potential to become candidate vaccines for TB therapy.
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Affiliation(s)
- Xuejuan Bai
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Dongfang Wang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Yinping Liu
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Li Xiao
- Institute for Organ Transplantation, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Yan Liang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Yourong Yang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Junxian Zhang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Minggui Lin
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China
| | - Xueqiong Wu
- Army Tuberculosis Prevention and Control Key Laboratory, Beijng Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, The 309th Hospital of Chinese PLA, Beijing 100091, PR China.
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25
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Loureiro RJS, Vila-Viçosa D, Machuqueiro M, Shakhnovich EI, Faísca PFN. A tale of two tails: The importance of unstructured termini in the aggregation pathway of β2-microglobulin. Proteins 2017; 85:2045-2057. [DOI: 10.1002/prot.25358] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 07/13/2017] [Accepted: 07/22/2017] [Indexed: 12/14/2022]
Affiliation(s)
- Rui J. S. Loureiro
- BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa; Lisboa Portugal
| | - Diogo Vila-Viçosa
- Centro de Química e Bioquímica; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa; Lisboa Portugal
| | - Miguel Machuqueiro
- Centro de Química e Bioquímica; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa; Lisboa Portugal
| | - Eugene I. Shakhnovich
- Department of Chemistry and Chemical Biology; Harvard University; Cambridge Massachusetts
| | - Patricia F. N. Faísca
- BioISI - Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa; Lisboa Portugal
- Departamento de Física; Faculdade de Ciências, Universidade de Lisboa; Lisboa Portugal
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26
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Ayres CM, Riley TP, Corcelli SA, Baker BM. Modeling Sequence-Dependent Peptide Fluctuations in Immunologic Recognition. J Chem Inf Model 2017; 57:1990-1998. [PMID: 28696685 DOI: 10.1021/acs.jcim.7b00118] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In cellular immunity, T cells recognize peptide antigens bound and presented by major histocompatibility complex (MHC) proteins. The motions of peptides bound to MHC proteins play a significant role in determining immunogenicity. However, existing approaches for investigating peptide/MHC motional dynamics are challenging or of low throughput, hindering the development of algorithms for predicting immunogenicity from large databases, such as those of tumor or genetically unstable viral genomes. We addressed this by performing extensive molecular dynamics simulations on a large structural database of peptides bound to the most commonly expressed human class-I MHC protein, HLA-A*0201. The simulations reproduced experimental indicators of motion and were used to generate simple models for predicting site-specific, rapid motions of bound peptides through differences in their sequence and chemical composition alone. The models can easily be applied on their own or incorporated into immunogenicity prediction algorithms. Beyond their predictive power, the models provide insight into how amino acid substitutions can influence peptide and protein motions and how dynamic information is communicated across peptides. They also indicate a link between peptide rigidity and hydrophobicity, two features known to be important in influencing cellular immune responses.
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Affiliation(s)
- Cory M Ayres
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Timothy P Riley
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Steven A Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Brian M Baker
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
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27
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Xiao Z, Ye Z, Tadwal VS, Shen M, Ren EC. Dual non-contiguous peptide occupancy of HLA class I evoke antiviral human CD8 T cell response and form neo-epitopes with self-antigens. Sci Rep 2017; 7:5072. [PMID: 28698575 PMCID: PMC5505988 DOI: 10.1038/s41598-017-05171-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/24/2017] [Indexed: 01/27/2023] Open
Abstract
Host CD8 T cell response to viral infections involves recognition of 8-10-mer peptides presented by MHC-I molecules. However, proteasomes generate predominantly 2-7-mer peptides, but the role of these peptides is largely unknown. Here, we show that single short peptides of <8-mer from Latent Membrane Protein 2 (LMP2) of Epstein Barr Virus (EBV) can bind HLA-A*11:01 and stimulate CD8+ cells. Surprisingly, two peptide fragments between 4-7-mer derived from LMP2(340-349) were able to complement each other, forming combination epitopes that can stimulate specific CD8+ T cell responses. Moreover, peptides from self-antigens can complement non-self peptides within the HLA binding cleft, forming neoepitopes. Solved structures of a tetra-complex comprising two peptides, HLA and β2-microglobulin revealed the free terminals of the two peptides to adopt an upward conformation directed towards the T cell receptor. Our results demonstrate a previously unknown mix-and-match combination of dual peptide occupancy in HLA that can generate vast combinatorial complexity.
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Affiliation(s)
- Ziwei Xiao
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #03-06 Immunos, Singapore, 138648, Singapore
| | - Zhiyong Ye
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #03-06 Immunos, Singapore, 138648, Singapore
| | - Vikeramjeet Singh Tadwal
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #03-06 Immunos, Singapore, 138648, Singapore
| | - Meixin Shen
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #03-06 Immunos, Singapore, 138648, Singapore
| | - Ee Chee Ren
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), 8A Biomedical Grove, #03-06 Immunos, Singapore, 138648, Singapore.
- Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore, 119260, Singapore.
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28
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Zhang YH, Xing Z, Liu C, Wang S, Huang T, Cai YD, Kong X. Identification of the core regulators of the HLA I-peptide binding process. Sci Rep 2017; 7:42768. [PMID: 28211542 PMCID: PMC5314381 DOI: 10.1038/srep42768] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/13/2017] [Indexed: 12/16/2022] Open
Abstract
During the display of peptide/human leukocyte antigen (HLA) -I complex for further immune recognition, the cleaved and transported antigenic peptides have to bind to HLA-I protein and the binding affinity between peptide epitopes and HLA proteins directly influences the immune recognition ability in human beings. Key factors affecting the binding affinity during the generation, selection and presentation processes of HLA-I complex have not yet been fully discovered. In this study, a new method describing the HLA class I-peptide interactions was proposed. Three hundred and forty features of HLA I proteins and peptide sequences were utilized for analysis by four candidate algorithms, screening the optimal classifier. Features derived from the optimal classifier were further selected and systematically analyzed, revealing the core regulators. The results validated the hypothesis that features of HLA I proteins and related peptides simultaneously affect the binding process, though with discrepant redundancy. Besides, the high relative ratio (16/20) of the amino acid composition features suggests the unique role of sequence signatures for the binding processes. Integrating biological, evolutionary and chemical features of both HLA I molecules and peptides, this study may provide a new perspective of the underlying mechanisms of HLA I-mediated immune reactions.
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Affiliation(s)
- Yu-Hang Zhang
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - Zhihao Xing
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - Chenglin Liu
- School of Life Sciences and Biotechnology, Shanghai Jiaotong University, Shanghai 200240, People's Republic of China
| | - ShaoPeng Wang
- School of Life Sciences, Shanghai University, Shanghai 200444, People's Republic of China
| | - Tao Huang
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - Yu-Dong Cai
- School of Life Sciences, Shanghai University, Shanghai 200444, People's Republic of China
| | - Xiangyin Kong
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
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29
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Guasp P, Alvarez-Navarro C, Gomez-Molina P, Martín-Esteban A, Marcilla M, Barnea E, Admon A, López de Castro JA. The Peptidome of Behçet's Disease-Associated HLA-B*51:01 Includes Two Subpeptidomes Differentially Shaped by Endoplasmic Reticulum Aminopeptidase 1. Arthritis Rheumatol 2016; 68:505-15. [PMID: 26360328 DOI: 10.1002/art.39430] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 09/03/2015] [Indexed: 01/09/2023]
Abstract
OBJECTIVE To characterize the peptidome of the Behçet's disease-associated HLA-B*51:01 allotype as well as the differential features of major peptide subsets and their distinct endoplasmic reticulum aminopeptidase 1 (ERAP-1)-mediated processing. METHODS The endogenous B*51:01-bound peptidome was characterized from 721.221 transfectant cells, after affinity chromatography and acid extraction, by tandem mass spectrometry. Recombinant ERAP-1 variants were used to digest synthetic B*51:01 ligands. HLA and transporter associated with antigen processing (TAP) binding affinities of peptide ligands were calculated with well-established algorithms. ERAP-1 and ERAP-2 from 721.221 cells were characterized by genomic sequencing and Western blotting. RESULTS The B*51:01 peptidome consisted of 29.5% octamers, 61.7% nonamers, 4.8% decamers, and 4.0% longer peptides. The major peptide motif consisted of Pro and Ala at position 2, aliphatic/aromatic position 3 residues, and Val and Ile at the C-terminal position. The ligands with Pro or Ala at position 2 constituted 2 distinct subpeptidomes. Peptides with Pro at position 2 showed higher affinity for B*51:01 and lower affinity for TAP than those with Ala at position 2. Most important, both peptide subsets differed drastically in the susceptibility of their position 1 residues to ERAP-1, revealing a distinct influence of this enzyme on both subpeptidomes, which may alter their balance, affecting the global affinity of B*51:01-peptide complexes. CONCLUSION ERAP-1 has a significant influence on the B*51:01 peptidome and its affinity. This influence is based on very distinct effects on the 2 subpeptidomes, whereby only peptides in the subpeptidome with Ala at position 2 are extensively destroyed, except when their position 1 residues are ERAP-1 resistant. This pattern provides a mechanism for the epistatic association of ERAP-1 and B*51:01 in Behçet's disease.
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Affiliation(s)
- Pablo Guasp
- CSIC, Centro de Biología Molecular Severo Ochoa, Madrid, Spain
| | | | | | | | | | - Eilon Barnea
- Technion-Israel Institute of Technology, Haifa, Israel
| | - Arie Admon
- Technion-Israel Institute of Technology, Haifa, Israel
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30
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Tedeschi V, Vitulano C, Cauli A, Paladini F, Piga M, Mathieu A, Sorrentino R, Fiorillo MT. The Ankylosing Spondylitis-associated HLA-B*2705 presents a B*0702-restricted EBV epitope and sustains the clonal amplification of cytotoxic T cells in patients. Mol Med 2016; 22:215-223. [PMID: 27254288 DOI: 10.2119/molmed.2016.00031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 05/11/2016] [Indexed: 12/16/2022] Open
Abstract
HLA-B*27 is strongly associated with an inflammatory autoimmune disorder, the Ankylosing Spondylitis (AS) and plays a protective role in viral infections. The two aspects might be linked. In this work, we compared in B*2705/B*07 positive patients with AS, the CD8+ T cell responses to two immunodominant EBV-derived epitopes restricted for either the HLA-B*27 (pEBNA3C) or the HLA-B*07 (pEBNA3A). We have unexpectedly found that the HLA-B*07-restricted EBNA3A peptide is presented by both the B*0702 and the B*2705 but not by the non AS-associated B*2709, that differs from the AS-associated B*2705 for a single amino acid in the peptide-binding groove (His116Asp). We then analysed 38 B*2705-positive/B*07-negative (31 AS-patients and 7 healthy donors) and 8 B*2709-positive/B*07-negative subjects. EBNA3A-specific CD8+ T lymphocytes were present in 55.3% of the HLA-B*2705 but in none of the B*2709 donors (p=0.0049). TCR β-chain analysis identified common TCRBV and TCRBJ gene segments and shared CDR3β sequences in pEBNA3A-responsive CTLs of B*2705 carriers, suggesting the existence of a shared TCR repertoire for recognition of the uncanonical B*2705/pEBNA3A complex. These data highlight the plasticity of the AS-associated HLA-B*2705, which presents peptides with suboptimal binding motifs, possibly contributing both to its enhanced capacity to protect against pathogens and to predispose to autoimmunity.
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Affiliation(s)
- Valentina Tedeschi
- Department of Biology and Biotechnology "C. Darwin", Sapienza University, Rome, Italy
| | - Carolina Vitulano
- Department of Biology and Biotechnology "C. Darwin", Sapienza University, Rome, Italy
| | - Alberto Cauli
- 2nd Chair of Rheumatology, Department of Medical Sciences, University of Cagliari, Cagliari, Italy
| | - Fabiana Paladini
- Department of Biology and Biotechnology "C. Darwin", Sapienza University, Rome, Italy
| | - Matteo Piga
- 2nd Chair of Rheumatology, Department of Medical Sciences, University of Cagliari, Cagliari, Italy
| | - Alessandro Mathieu
- 2nd Chair of Rheumatology, Department of Medical Sciences, University of Cagliari, Cagliari, Italy
| | - Rosa Sorrentino
- Department of Biology and Biotechnology "C. Darwin", Sapienza University, Rome, Italy
| | - Maria Teresa Fiorillo
- Department of Biology and Biotechnology "C. Darwin", Sapienza University, Rome, Italy
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31
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Rühl G, Niedl AG, Patronov A, Siewert K, Pinkert S, Kalemanov M, Friese MA, Attfield KE, Antes I, Hohlfeld R, Dornmair K. Multiple sclerosis: Molecular mimicry of an antimyelin HLA class I restricted T-cell receptor. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2016; 3:e241. [PMID: 27231714 PMCID: PMC4871805 DOI: 10.1212/nxi.0000000000000241] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 04/01/2016] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To identify target antigens presented by human leukocyte antigen (HLA)-A*02:01 to the myelin-reactive human T-cell receptor (TCR) 2D1, which was originally isolated from a CD8+ T-cell clone recognizing proteolipid protein (PLP) in the context of HLA-A*03:01, we employed a new antigen search technology. METHODS We used our recently developed antigen search technology that employs plasmid-encoded combinatorial peptide libraries and a highly sensitive single cell detection system to identify endogenous candidate peptides of mice and human origin. We validated candidate antigens by independent T-cell assays using synthetic peptides and refolded HLA:peptide complexes. A molecular model of HLA-A*02:01:peptide complexes was obtained by molecular dynamics simulations. RESULTS We identified one peptide from glycerolphosphatidylcholine phosphodiesterase 1, which is identical in mice and humans and originates from a protein that is expressed in many cell types. When bound to HLA-A*02:01, this peptide cross-stimulates the PLP-reactive HLA-A3-restricted TCR 2D1. Investigation of molecular details revealed that the peptide length plays a crucial role in its capacity to bind HLA-A*02:01 and to activate TCR 2D1. Molecular modeling illustrated the 3D structures of activating HLA:peptide complexes. CONCLUSIONS Our results show that our antigen search technology allows us to identify new candidate antigens of a presumably pathogenic, autoreactive, human CD8+ T-cell-derived TCR. They further illustrate how this TCR, which recognizes a myelin peptide bound to HLA-A*03:01, may cross-react with an unrelated peptide presented by the protective HLA class I allele HLA-A*02:01.
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Affiliation(s)
- Geraldine Rühl
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Anna G Niedl
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Atanas Patronov
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Katherina Siewert
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Stefan Pinkert
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Maria Kalemanov
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Manuel A Friese
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Kathrine E Attfield
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Iris Antes
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Reinhard Hohlfeld
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
| | - Klaus Dornmair
- Institute of Clinical Neuroimmunology (G.R., A.G.N., K.S., R.H., K.D.) and Munich Cluster for Systems Neurology (SyNergy) (R.H., K.D.), Ludwig-Maximilian-University, Munich; Department of Life Sciences (A.P., M.K., I.A.), Technical University Munich, Freising; Max Planck Institute of Biochemistry (S.P.), Martinsried; Institute of Neuroimmunology and Multiple Sclerosis (M.A.F.), University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; MRC Human Immunology Unit (K.E.A.), Radcliffe Department of Medicine, Weatherall, Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, UK; and Center for Integrated Protein Science Munich (CIPSM) (I.A.), Germany
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Spear TT, Riley TP, Lyons GE, Callender GG, Roszkowski JJ, Wang Y, Simms PE, Scurti GM, Foley KC, Murray DC, Hellman LM, McMahan RH, Iwashima M, Garrett-Mayer E, Rosen HR, Baker BM, Nishimura MI. Hepatitis C virus-cross-reactive TCR gene-modified T cells: a model for immunotherapy against diseases with genomic instability. J Leukoc Biol 2016; 100:545-57. [PMID: 26921345 DOI: 10.1189/jlb.2a1215-561r] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/08/2016] [Indexed: 12/20/2022] Open
Abstract
A major obstacle hindering the development of effective immunity against viral infections, their associated disease, and certain cancers is their inherent genomic instability. Accumulation of mutations can alter processing and presentation of antigens recognized by antibodies and T cells that can lead to immune escape variants. Use of an agent that can intrinsically combat rapidly mutating viral or cancer-associated antigens would be quite advantageous in developing effective immunity against such disease. We propose that T cells harboring cross-reactive TCRs could serve as a therapeutic agent in these instances. With the use of hepatitis C virus, known for its genomic instability as a model for mutated antigen recognition, we demonstrate cross-reactivity against immunogenic and mutagenic nonstructural protein 3:1406-1415 and nonstructural protein 3:1073-1081 epitopes in PBL-derived, TCR-gene-modified T cells. These single TCR-engineered T cells can CD8-independently recognize naturally occurring and epidemiologically relevant mutant variants. TCR-peptide MHC modeling data allow us to rationalize how TCR structural properties accommodate recognition of certain mutated epitopes and how these substitutions impact the requirement of CD8 affinity enhancement for recognition. A better understanding of such TCRs' promiscuous behavior may allow for exploitation of these properties to develop novel, adoptive T cell-based therapies for viral infections and cancers exhibiting similar genomic instability.
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Affiliation(s)
- Timothy T Spear
- Department of Surgery, Cardinal Bernardin Cancer Center, Loyola University Chicago, Maywood, Illinois, USA;
| | - Timothy P Riley
- Department of Chemistry and Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana, USA
| | - Gretchen E Lyons
- Department of Surgery, University of Chicago, Chicago, Illinois, USA; Department of Biology, Northeastern Illinois University, Chicago, Illinois, USA
| | - Glenda G Callender
- Department of Surgery, University of Chicago, Chicago, Illinois, USA; Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | - Yuan Wang
- Department of Chemistry and Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana, USA
| | - Patricia E Simms
- Flow Cytometry Core Facility, Cardinal Bernardin Cancer Center, Loyola University Chicago, Maywood, Illinois, USA
| | - Gina M Scurti
- Department of Surgery, Cardinal Bernardin Cancer Center, Loyola University Chicago, Maywood, Illinois, USA
| | - Kendra C Foley
- Department of Surgery, Cardinal Bernardin Cancer Center, Loyola University Chicago, Maywood, Illinois, USA
| | - David C Murray
- Department of Surgery, Cardinal Bernardin Cancer Center, Loyola University Chicago, Maywood, Illinois, USA
| | - Lance M Hellman
- Department of Chemistry and Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana, USA
| | - Rachel H McMahan
- Division of Gastroenterology and Hepatology, Hepatitis C Center, and Department of Medicine, University of Colorado Health Sciences Center, Aurora, Colorado, USA; and
| | - Makio Iwashima
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois, USA
| | - Elizabeth Garrett-Mayer
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina, USA Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Hugo R Rosen
- Division of Gastroenterology and Hepatology, Hepatitis C Center, and Department of Medicine, University of Colorado Health Sciences Center, Aurora, Colorado, USA; and
| | - Brian M Baker
- Department of Chemistry and Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana, USA
| | - Michael I Nishimura
- Department of Surgery, Cardinal Bernardin Cancer Center, Loyola University Chicago, Maywood, Illinois, USA; Department of Surgery, University of Chicago, Chicago, Illinois, USA
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33
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Differential scanning fluorimetry based assessments of the thermal and kinetic stability of peptide-MHC complexes. J Immunol Methods 2016; 432:95-101. [PMID: 26906089 DOI: 10.1016/j.jim.2016.02.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 02/17/2016] [Accepted: 02/17/2016] [Indexed: 11/20/2022]
Abstract
Measurements of thermal stability by circular dichroism (CD) spectroscopy have been widely used to assess the binding of peptides to MHC proteins, particularly within the structural immunology community. Although thermal stability assays offer advantages over other approaches such as IC50 measurements, CD-based stability measurements are hindered by large sample requirements and low throughput. Here we demonstrate that an alternative approach based on differential scanning fluorimetry (DSF) yields results comparable to those based on CD for both class I and class II complexes. As they require much less sample, DSF-based measurements reduce demands on protein production strategies and are amenable for high throughput studies. DSF can thus not only replace CD as a means to assess peptide/MHC thermal stability, but can complement other peptide-MHC binding assays used in screening, epitope discovery, and vaccine design. Due to the physical process probed, DSF can also uncover complexities not observed with other techniques. Lastly, we show that DSF can also be used to assess peptide/MHC kinetic stability, allowing for a single experimental setup to probe both binding equilibria and kinetics.
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34
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How structural adaptability exists alongside HLA-A2 bias in the human αβ TCR repertoire. Proc Natl Acad Sci U S A 2016; 113:E1276-85. [PMID: 26884163 DOI: 10.1073/pnas.1522069113] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
How T-cell receptors (TCRs) can be intrinsically biased toward MHC proteins while simultaneously display the structural adaptability required to engage diverse ligands remains a controversial puzzle. We addressed this by examining αβ TCR sequences and structures for evidence of physicochemical compatibility with MHC proteins. We found that human TCRs are enriched in the capacity to engage a polymorphic, positively charged "hot-spot" region that is almost exclusive to the α1-helix of the common human class I MHC protein, HLA-A*0201 (HLA-A2). TCR binding necessitates hot-spot burial, yielding high energetic penalties that must be offset via complementary electrostatic interactions. Enrichment of negative charges in TCR binding loops, particularly the germ-line loops encoded by the TCR Vα and Vβ genes, provides this capacity and is correlated with restricted positioning of TCRs over HLA-A2. Notably, this enrichment is absent from antibody genes. The data suggest a built-in TCR compatibility with HLA-A2 that biases receptors toward, but does not compel, particular binding modes. Our findings provide an instructional example for how structurally pliant MHC biases can be encoded within TCRs.
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35
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Abstract
T-cell receptor (TCR) binding to peptide/MHC determines specificity and initiates signaling in antigen-specific cellular immune responses. Structures of TCR-pMHC complexes have provided enormous insight to cellular immune functions, permitted a rational understanding of processes such as pathogen escape, and led to the development of novel approaches for the design of vaccines and other therapeutics. As production, crystallization, and structure determination of TCR-pMHC complexes can be challenging, there is considerable interest in modeling new complexes. Here we describe a rapid approach to TCR-pMHC modeling that takes advantage of structural features conserved in known complexes, such as the restricted TCR binding site and the generally conserved diagonal docking mode. The approach relies on the powerful Rosetta suite and is implemented using the PyRosetta scripting environment. We show how the approach can recapitulate changes in TCR binding angles and other structural details, and highlight areas where careful evaluation of parameters is needed and alternative choices might be made. As TCRs are highly sensitive to subtle structural perturbations, there is room for improvement. Our method nonetheless generates high-quality models that can be foundational for structure-based hypotheses regarding TCR recognition.
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Affiliation(s)
- Timothy P Riley
- Department of Chemistry and Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN, 46556, USA
- Harper Cancer Research Institute, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN, 46556, USA
| | - Nishant K Singh
- Department of Chemistry and Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN, 46556, USA
- Harper Cancer Research Institute, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN, 46556, USA
| | - Brian G Pierce
- Institute for Bioscience and Biotechnology Research, University of Maryland, 9600 Gudelsky Drive, Rockville, MD, 20850, USA
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Brian M Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN, 46556, USA.
- Harper Cancer Research Institute, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, IN, 46556, USA.
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36
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Sun Y, Liu Q. Differential structural dynamics and antigenicity of two similar influenza H5N1 virus HA-specific HLA-A*0201-restricted CLT epitopes. RSC Adv 2015. [DOI: 10.1039/c4ra08874c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The free RI-10 and KI-10 peptides showed bent rather than extended conformations as binding in the cleft of the HLA-A*0201 molecule, and KI-10–HLA-A*0201 processed a much higher flexibility than RI-10–HLA-A*0201.
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Affiliation(s)
- Yeping Sun
- CAS Key Laboratory of Pathogenic Microbiology and Immunology
- Institute of Microbiology
- Chinese Academy of Sciences
- Beijing 100101
- P. R. China
| | - Qian Liu
- Supercomputing Center
- Chinese Academy of Sciences
- Beijing 100101
- P. R. China
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37
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Simmerman RF, Dave AM, Bruce BD. Structure and function of POTRA domains of Omp85/TPS superfamily. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 308:1-34. [PMID: 24411168 DOI: 10.1016/b978-0-12-800097-7.00001-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The Omp85/TPS (outer-membrane protein of 85 kDa/two-partner secretion) superfamily is a ubiquitous and major class of β-barrel proteins. This superfamily is restricted to the outer membranes of gram-negative bacteria, mitochondria, and chloroplasts. The common architecture, with an N-terminus consisting of repeats of soluble polypeptide-transport-associated (POTRA) domains and a C-terminal β-barrel pore is highly conserved. The structures of multiple POTRA domains and one full-length TPS protein have been solved, yet discovering roles of individual POTRA domains has been difficult. This review focuses on similarities and differences between POTRA structures, emphasizing POTRA domains in autotrophic organisms including plants and cyanobacteria. Unique roles, specific for certain POTRA domains, are examined in the context of POTRA location with respect to their attachment to the β-barrel pore, and their degree of biological dispensability. Finally, because many POTRA domains may have the ability to interact with thousands of partner proteins, possible modes of these interactions are also explored.
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Affiliation(s)
- Richard F Simmerman
- Department of Biochemistry and Cellular and Molecular Biology, Knoxville, Tennessee, USA
| | - Ashita M Dave
- Department of Biochemistry and Cellular and Molecular Biology, Knoxville, Tennessee, USA
| | - Barry D Bruce
- Department of Biochemistry and Cellular and Molecular Biology, Knoxville, Tennessee, USA; Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA.
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Rossjohn J, Gras S, Miles JJ, Turner SJ, Godfrey DI, McCluskey J. T cell antigen receptor recognition of antigen-presenting molecules. Annu Rev Immunol 2014; 33:169-200. [PMID: 25493333 DOI: 10.1146/annurev-immunol-032414-112334] [Citation(s) in RCA: 508] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The Major Histocompatibility Complex (MHC) locus encodes classical MHC class I and MHC class II molecules and nonclassical MHC-I molecules. The architecture of these molecules is ideally suited to capture and present an array of peptide antigens (Ags). In addition, the CD1 family members and MR1 are MHC class I-like molecules that bind lipid-based Ags and vitamin B precursors, respectively. These Ag-bound molecules are subsequently recognized by T cell antigen receptors (TCRs) expressed on the surface of T lymphocytes. Structural and associated functional studies have been highly informative in providing insight into these interactions, which are crucial to immunity, and how they can lead to aberrant T cell reactivity. Investigators have determined over thirty unique TCR-peptide-MHC-I complex structures and twenty unique TCR-peptide-MHC-II complex structures. These investigations have shown a broad consensus in docking geometry and provided insight into MHC restriction. Structural studies on TCR-mediated recognition of lipid and metabolite Ags have been mostly confined to TCRs from innate-like natural killer T cells and mucosal-associated invariant T cells, respectively. These studies revealed clear differences between TCR-lipid-CD1, TCR-metabolite-MR1, and TCR-peptide-MHC recognition. Accordingly, TCRs show remarkable structural and biological versatility in engaging different classes of Ag that are presented by polymorphic and monomorphic Ag-presenting molecules of the immune system.
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Affiliation(s)
- Jamie Rossjohn
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria 3800, Australia; ,
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Smith SN, Wang Y, Baylon JL, Singh NK, Baker BM, Tajkhorshid E, Kranz DM. Changing the peptide specificity of a human T-cell receptor by directed evolution. Nat Commun 2014; 5:5223. [PMID: 25376839 PMCID: PMC4225554 DOI: 10.1038/ncomms6223] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 09/10/2014] [Indexed: 11/09/2022] Open
Abstract
Binding of a T-cell receptor (TCR) to a peptide/major histocompatibility complex is the key interaction involved in antigen specificity of T cells. The recognition involves up to six complementarity determining regions (CDR) of the TCR. Efforts to examine the structural basis of these interactions and to exploit them in adoptive T-cell therapies has required the isolation of specific T-cell clones and their clonotypic TCRs. Here we describe a strategy using in vitro-directed evolution of a single TCR to change its peptide specificity, thereby avoiding the need to isolate T-cell clones. The human TCR A6, which recognizes the viral peptide Tax/HLA-A2, was converted to TCR variants that recognized the cancer peptide MART1/HLA-A2. Mutational studies and molecular dynamics simulations identified CDR residues that were predicted to be important in the specificity switch. Thus, in vitro engineering strategies alone can be used to discover TCRs with desired specificities.
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Affiliation(s)
- Sheena N. Smith
- Department of Biochemistry, University of Illinois, 600 S. Matthews Ave., Urbana, IL 61801, USA
| | - Yuhang Wang
- Center for Biophysics and Computational Biology, University of Illinois, Urbana, IL 61802, USA
| | - Javier L. Baylon
- Center for Biophysics and Computational Biology, University of Illinois, Urbana, IL 61802, USA
| | - Nishant K. Singh
- Department of Chemistry and Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, 1234 Notre Dame Avenue, South Bend, IN 46557, USA
| | - Brian M. Baker
- Department of Chemistry and Biochemistry and the Harper Cancer Research Institute, University of Notre Dame, 1234 Notre Dame Avenue, South Bend, IN 46557, USA
| | - Emad Tajkhorshid
- Department of Biochemistry, University of Illinois, 600 S. Matthews Ave., Urbana, IL 61801, USA
- Center for Biophysics and Computational Biology, University of Illinois, Urbana, IL 61802, USA
| | - David M. Kranz
- Department of Biochemistry, University of Illinois, 600 S. Matthews Ave., Urbana, IL 61801, USA
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40
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Su Y, Sarell CJ, Eddy MT, Debelouchina GT, Andreas LB, Pashley CL, Radford SE, Griffin RG. Secondary structure in the core of amyloid fibrils formed from human β₂m and its truncated variant ΔN6. J Am Chem Soc 2014; 136:6313-25. [PMID: 24679070 PMCID: PMC4017606 DOI: 10.1021/ja4126092] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
![]()
Amyloid
fibrils formed from initially soluble proteins with diverse
sequences are associated with an array of human diseases. In the human
disorder, dialysis-related amyloidosis (DRA), fibrils contain two
major constituents, full-length human β2-microglobulin
(hβ2m) and a truncation variant, ΔN6 which
lacks the N-terminal six amino acids. These fibrils are assembled
from initially natively folded proteins with an all antiparallel β-stranded
structure. Here, backbone conformations of wild-type hβ2m and ΔN6 in their amyloid forms have been determined
using a combination of dilute isotopic labeling strategies and multidimensional
magic angle spinning (MAS) NMR techniques at high magnetic fields,
providing valuable structural information at the atomic-level about
the fibril architecture. The secondary structures of both fibril types,
determined by the assignment of ∼80% of the backbone resonances
of these 100- and 94-residue proteins, respectively, reveal substantial
backbone rearrangement compared with the location of β-strands
in their native immunoglobulin folds. The identification of seven
β-strands in hβ2m fibrils indicates that approximately
70 residues are in a β-strand conformation in the fibril core.
By contrast, nine β-strands comprise the fibrils formed from
ΔN6, indicating a more extensive core. The precise location
and length of β-strands in the two fibril forms also differ.
The results indicate fibrils of ΔN6 and hβ2m have an extensive core architecture involving the majority of residues
in the polypeptide sequence. The common elements of the backbone structure
of the two proteins likely facilitates their ability to copolymerize
during amyloid fibril assembly.
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Affiliation(s)
- Yongchao Su
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology Cambridge, Massachusetts 02139, United States
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Pierce BG, Hellman LM, Hossain M, Singh NK, Vander Kooi CW, Weng Z, Baker BM. Computational design of the affinity and specificity of a therapeutic T cell receptor. PLoS Comput Biol 2014; 10:e1003478. [PMID: 24550723 PMCID: PMC3923660 DOI: 10.1371/journal.pcbi.1003478] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 01/02/2014] [Indexed: 01/15/2023] Open
Abstract
T cell receptors (TCRs) are key to antigen-specific immunity and are increasingly being explored as therapeutics, most visibly in cancer immunotherapy. As TCRs typically possess only low-to-moderate affinity for their peptide/MHC (pMHC) ligands, there is a recognized need to develop affinity-enhanced TCR variants. Previous in vitro engineering efforts have yielded remarkable improvements in TCR affinity, yet concerns exist about the maintenance of peptide specificity and the biological impacts of ultra-high affinity. As opposed to in vitro engineering, computational design can directly address these issues, in theory permitting the rational control of peptide specificity together with relatively controlled increments in affinity. Here we explored the efficacy of computational design with the clinically relevant TCR DMF5, which recognizes nonameric and decameric epitopes from the melanoma-associated Melan-A/MART-1 protein presented by the class I MHC HLA-A2. We tested multiple mutations selected by flexible and rigid modeling protocols, assessed impacts on affinity and specificity, and utilized the data to examine and improve algorithmic performance. We identified multiple mutations that improved binding affinity, and characterized the structure, affinity, and binding kinetics of a previously reported double mutant that exhibits an impressive 400-fold affinity improvement for the decameric pMHC ligand without detectable binding to non-cognate ligands. The structure of this high affinity mutant indicated very little conformational consequences and emphasized the high fidelity of our modeling procedure. Overall, our work showcases the capability of computational design to generate TCRs with improved pMHC affinities while explicitly accounting for peptide specificity, as well as its potential for generating TCRs with customized antigen targeting capabilities.
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Affiliation(s)
- Brian G. Pierce
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Lance M. Hellman
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Moushumi Hossain
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Nishant K. Singh
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Craig W. Vander Kooi
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, United States of America
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Brian M. Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, United States of America
- Harper Cancer Research Institute, University of Notre Dame, Notre Dame, Indiana, United States of America
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EGFR T790M mutation as a possible target for immunotherapy; identification of HLA-A*0201-restricted T cell epitopes derived from the EGFR T790M mutation. PLoS One 2013; 8:e78389. [PMID: 24223798 PMCID: PMC3818324 DOI: 10.1371/journal.pone.0078389] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 09/19/2013] [Indexed: 12/22/2022] Open
Abstract
Treatment with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib and erlotinib, has achieved high clinical response rates in patients with non–small cell lung cancers (NSCLCs). However, over time, most tumors develop acquired resistance to EGFR-TKIs, which is associated with the secondary EGFR T790M resistance mutation in about half the cases. Currently there are no effective treatment options for patients with this resistance mutation. Here we identified two novel HLA-A*0201 (A2)-restricted T cell epitopes containing the mutated methionine residue of the EGFR T790M mutation, T790M-5 (MQLMPFGCLL) and T790M-7 (LIMQLMPFGCL), as potential targets for EGFR-TKI-resistant patients. When peripheral blood cells were repeatedly stimulated in vitro with these two peptides and assessed by antigen-specific IFN-γ secretion, T cell lines responsive to T790M-5 and T790M-7 were established in 5 of 6 (83%) and 3 of 6 (50%) healthy donors, respectively. Additionally, the T790M-5- and T790M-7-specific T cell lines displayed an MHC class I-restricted reactivity against NSCLC cell lines expressing both HLA-A2 and the T790M mutation. Interestingly, the NSCLC patients with antigen-specific T cell responses to these epitopes showed a significantly less frequency of EGFR-T790M mutation than those without them [1 of 7 (14%) vs 9 of 15 (60%); chi-squared test, p = 0.0449], indicating the negative correlation between the immune responses to the EGFR-T790M-derived epitopes and the presence of EGFR-T790M mutation in NSCLC patients. This finding could possibly be explained by the hypothesis that immune responses to the mutated neo-antigens derived from T790M might prevent the emergence of tumor cell variants with the T790M resistance mutation in NSCLC patients during EGFR-TKI treatment. Together, our results suggest that the identified T cell epitopes might provide a novel immunotherapeutic approach for prevention and/or treatment of EGFR-TKI resistance with the secondary EGFR T790M resistance mutation in NSCLC patients.
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Abstract
MHC class I molecules bind only those peptides with high affinity that conform to stringent length and sequence requirements. We have now investigated which peptides can aid the in vitro folding of class I molecules, and we find that the dipeptide glycyl-leucine efficiently supports the folding of HLA-A*02:01 and H-2K(b) into a peptide-receptive conformation that rapidly binds high-affinity peptides. Treatment of cells with glycyl-leucine induces accumulation of peptide-receptive H-2K(b) and HLA-A*02:01 at the surface of cells. Other dipeptides with a hydrophobic second amino acid show similar enhancement effects. Our data suggest that the dipeptides bind into the F pocket like the C-terminal amino acids of a high-affinity peptide.
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Vanderhaegen S, Fislage M, Domanska K, Versées W, Pardon E, Bellotti V, Steyaert J. Structure of an early native-like intermediate of β2-microglobulin amyloidogenesis. Protein Sci 2013; 22:1349-57. [PMID: 23904325 DOI: 10.1002/pro.2321] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 07/19/2013] [Accepted: 07/22/2013] [Indexed: 11/06/2022]
Abstract
To investigate early intermediates of β2-microglobulin (β2m) amyloidogenesis, we solved the structure of β2m containing the amyloidogenic Pro32Gly mutation by X-ray crystallography. One nanobody (Nb24) that efficiently blocks fibril elongation was used as a chaperone to co-crystallize the Pro32Gly β2m monomer under physiological conditions. The complex of P32G β2m with Nb24 reveals a trans peptide bond at position 32 of this amyloidogenic variant, whereas Pro32 adopts the cis conformation in the wild-type monomer, indicating that the cis to trans isomerization at Pro32 plays a critical role in the early onset of β2m amyloid formation.
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Affiliation(s)
- Saskia Vanderhaegen
- Structural Biology Research Centre, VIB, Pleinlaan 2, 1050, Brussel, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussel, Belgium
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45
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Hawse WF, Gloor BE, Ayres CM, Kho K, Nuter E, Baker BM. Peptide modulation of class I major histocompatibility complex protein molecular flexibility and the implications for immune recognition. J Biol Chem 2013; 288:24372-81. [PMID: 23836912 DOI: 10.1074/jbc.m113.490664] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
T cells use the αβ T cell receptor (TCR) to recognize antigenic peptides presented by class I major histocompatibility complex proteins (pMHCs) on the surfaces of antigen-presenting cells. Flexibility in both TCRs and peptides plays an important role in antigen recognition and discrimination. Less clear is the role of flexibility in the MHC protein; although recent observations have indicated that mobility in the MHC can impact TCR recognition in a peptide-dependent fashion, the extent of this behavior is unknown. Here, using hydrogen/deuterium exchange, fluorescence anisotropy, and structural analyses, we show that the flexibility of the peptide binding groove of the class I MHC protein HLA-A*0201 varies significantly with different peptides. The variations extend throughout the binding groove, impacting regions contacted by TCRs as well as other activating and inhibitory receptors of the immune system. Our results are consistent with statistical mechanical models of protein structure and dynamics, in which the binding of different peptides alters the populations and exchange kinetics of substates in the MHC conformational ensemble. Altered MHC flexibility will influence receptor engagement, impacting conformational adaptations, entropic penalties associated with receptor recognition, and the populations of binding-competent states. Our results highlight a previously unrecognized aspect of the "altered self" mechanism of immune recognition and have implications for specificity, cross-reactivity, and antigenicity in cellular immunity.
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Affiliation(s)
- William F Hawse
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Koch CP, Perna AM, Pillong M, Todoroff NK, Wrede P, Folkers G, Hiss JA, Schneider G. Scrutinizing MHC-I binding peptides and their limits of variation. PLoS Comput Biol 2013; 9:e1003088. [PMID: 23754940 PMCID: PMC3674988 DOI: 10.1371/journal.pcbi.1003088] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Accepted: 04/23/2013] [Indexed: 12/20/2022] Open
Abstract
Designed peptides that bind to major histocompatibility protein I (MHC-I) allomorphs bear the promise of representing epitopes that stimulate a desired immune response. A rigorous bioinformatical exploration of sequence patterns hidden in peptides that bind to the mouse MHC-I allomorph H-2Kb is presented. We exemplify and validate these motif findings by systematically dissecting the epitope SIINFEKL and analyzing the resulting fragments for their binding potential to H-2Kb in a thermal denaturation assay. The results demonstrate that only fragments exclusively retaining the carboxy- or amino-terminus of the reference peptide exhibit significant binding potential, with the N-terminal pentapeptide SIINF as shortest ligand. This study demonstrates that sophisticated machine-learning algorithms excel at extracting fine-grained patterns from peptide sequence data and predicting MHC-I binding peptides, thereby considerably extending existing linear prediction models and providing a fresh view on the computer-based molecular design of future synthetic vaccines. The server for prediction is available at http://modlab-cadd.ethz.ch (SLiDER tool, MHC-I version 2012). Future success in vaccine development will critically depend on identifying potent epitopes with reduced side effects. Among such candidate molecules, immunogenic peptides binding to major histocompatibility protein I (MHC-I) represent a preferred class of biomolecules for vaccine design. Computational models assist in the selection of the best candidate peptides by providing a mathematical rationale for antigen recognition by MHC-I. Here we present a machine-learning model that was trained on recognizing features of known MHC-I binding and non-binding peptide sequences with sustained accuracy. We were able to biochemically validate the computational predictions in a direct binding assay measuring complex formation between synthesized candidate peptides and MHC-I. Strong correspondence between the predictions and the experimentally determined binding potential corroborate the machine-learning model as viable for future antigen design. Thus, our study provides a concept for rapidly finding innovative MHC-I binding peptides with limited experimental effort.
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Affiliation(s)
- Christian P. Koch
- ETH Zürich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zürich, Switzerland
| | - Anna M. Perna
- ETH Zürich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zürich, Switzerland
| | - Max Pillong
- ETH Zürich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zürich, Switzerland
| | - Nickolay K. Todoroff
- ETH Zürich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zürich, Switzerland
| | - Paul Wrede
- Charite-Universitätsmedizin Berlin, Molekularbiologie und Bioinformatik, Berlin, Germany
| | - Gerd Folkers
- ETH Zürich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zürich, Switzerland
| | - Jan A. Hiss
- ETH Zürich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zürich, Switzerland
| | - Gisbert Schneider
- ETH Zürich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Zürich, Switzerland
- * E-mail:
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Saethang T, Hirose O, Kimkong I, Tran VA, Dang XT, Nguyen LAT, Le TKT, Kubo M, Yamada Y, Satou K. EpicCapo: epitope prediction using combined information of amino acid pairwise contact potentials and HLA-peptide contact site information. BMC Bioinformatics 2012; 13:313. [PMID: 23176036 PMCID: PMC3548761 DOI: 10.1186/1471-2105-13-313] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 11/15/2012] [Indexed: 11/10/2022] Open
Abstract
Background Epitope identification is an essential step toward synthetic vaccine development since epitopes play an important role in activating immune response. Classical experimental approaches are laborious and time-consuming, and therefore computational methods for generating epitope candidates have been actively studied. Most of these methods, however, are based on sophisticated nonlinear techniques for achieving higher predictive performance. The use of these techniques tend to diminish their interpretability with respect to binding potential: that is, they do not provide much insight into binding mechanisms. Results We have developed a novel epitope prediction method named EpicCapo and its variants, EpicCapo+ and EpicCapo+REF. Nonapeptides were encoded numerically using a novel peptide-encoding scheme for machine learning algorithms by utilizing 40 amino acid pairwise contact potentials (referred to as AAPPs throughout this paper). The predictive performances of EpicCapo+ and EpicCapo+REF outperformed other state-of-the-art methods without losing interpretability. Interestingly, the most informative AAPPs estimated by our study were those developed by Micheletti and Simons while previous studies utilized two AAPPs developed by Miyazawa & Jernigan and Betancourt & Thirumalai. In addition, we found that all amino acid positions in nonapeptides could effect on performances of the predictive models including non-anchor positions. Finally, EpicCapo+REF was applied to identify candidates of promiscuous epitopes. As a result, 67.1% of the predicted nonapeptides epitopes were consistent with preceding studies based on immunological experiments. Conclusions Our method achieved high performance in testing with benchmark datasets. In addition, our study identified a number of candidates of promiscuous CTL epitopes consistent with previously reported immunological experiments. We speculate that our techniques may be useful in the development of new vaccines. The R implementation of EpicCapo+REF is available at
http://pirun.ku.ac.th/~fsciiok/EpicCapoREF.zip. Datasets are available at
http://pirun.ku.ac.th/~fsciiok/Datasets.zip.
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Affiliation(s)
- Thammakorn Saethang
- Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Japan.
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Gras S, Burrows SR, Turner SJ, Sewell AK, McCluskey J, Rossjohn J. A structural voyage toward an understanding of the MHC-I-restricted immune response: lessons learned and much to be learned. Immunol Rev 2012; 250:61-81. [DOI: 10.1111/j.1600-065x.2012.01159.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Stephanie Gras
- Department of Biochemistry and Molecular Biology; School of Biomedical Sciences; Monash University; Clayton; Australia
| | - Scott R. Burrows
- Queensland Institute of Medical Research and Australian Centre for Vaccine Development; Brisbane; Australia
| | - Stephen J. Turner
- Department of Microbiology and Immunology; University of Melbourne; Parkville; Australia
| | - Andrew K. Sewell
- Institute of Infection and Immunity; Cardiff University School of Medicine; Cardiff; UK
| | - James McCluskey
- Department of Microbiology and Immunology; University of Melbourne; Parkville; Australia
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Ekeruche-Makinde J, Clement M, Cole DK, Edwards ESJ, Ladell K, Miles JJ, Matthews KK, Fuller A, Lloyd KA, Madura F, Dolton GM, Pentier J, Lissina A, Gostick E, Baxter TK, Baker BM, Rizkallah PJ, Price DA, Wooldridge L, Sewell AK. T-cell receptor-optimized peptide skewing of the T-cell repertoire can enhance antigen targeting. J Biol Chem 2012; 287:37269-81. [PMID: 22952231 PMCID: PMC3481325 DOI: 10.1074/jbc.m112.386409] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Altered peptide antigens that enhance T-cell immunogenicity have been used to improve peptide-based vaccination for a range of diseases. Although this strategy can prime T-cell responses of greater magnitude, the efficacy of constituent T-cell clonotypes within the primed population can be poor. To overcome this limitation, we isolated a CD8+ T-cell clone (MEL5) with an enhanced ability to recognize the HLA A*0201-Melan A27–35 (HLA A*0201-AAGIGILTV) antigen expressed on the surface of malignant melanoma cells. We used combinatorial peptide library screening to design an optimal peptide sequence that enhanced functional activation of the MEL5 clone, but not other CD8+ T-cell clones that recognized HLA A*0201-AAGIGILTV poorly. Structural analysis revealed the potential for new contacts between the MEL5 T-cell receptor and the optimized peptide. Furthermore, the optimized peptide was able to prime CD8+ T-cell populations in peripheral blood mononuclear cell isolates from multiple HLA A*0201+ individuals that were capable of efficient HLA A*0201+ melanoma cell destruction. This proof-of-concept study demonstrates that it is possible to design altered peptide antigens for the selection of superior T-cell clonotypes with enhanced antigen recognition properties.
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Affiliation(s)
- Julia Ekeruche-Makinde
- Institute of Infection and Immunity, Cardiff University School of Medicine, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, Wales, United Kingdom
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Prod'homme V, Tomasec P, Cunningham C, Lemberg MK, Stanton RJ, McSharry BP, Wang ECY, Cuff S, Martoglio B, Davison AJ, Braud VM, Wilkinson GWG. Human cytomegalovirus UL40 signal peptide regulates cell surface expression of the NK cell ligands HLA-E and gpUL18. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2012; 188:2794-804. [PMID: 22345649 PMCID: PMC3303119 DOI: 10.4049/jimmunol.1102068] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Human CMV (HCMV)-encoded NK cell-evasion functions include an MHC class I homolog (UL18) with high affinity for the leukocyte inhibitory receptor-1 (CD85j, ILT2, or LILRB1) and a signal peptide (SP(UL40)) that acts by upregulating cell surface expression of HLA-E. Detailed characterization of SP(UL40) revealed that the N-terminal 14 aa residues bestowed TAP-independent upregulation of HLA-E, whereas C region sequences delayed processing of SP(UL40) by a signal peptide peptidase-type intramembrane protease. Most significantly, the consensus HLA-E-binding epitope within SP(UL40) was shown to promote cell surface expression of both HLA-E and gpUL18. UL40 was found to possess two transcription start sites, with utilization of the downstream site resulting in translation being initiated within the HLA-E-binding epitope (P2). Remarkably, this truncated SP(UL40) was functional and retained the capacity to upregulate gpUL18 but not HLA-E. Thus, our findings identify an elegant mechanism by which an HCMV signal peptide differentially regulates two distinct NK cell-evasion pathways. Moreover, we describe a natural SP(UL40) mutant that provides a clear example of an HCMV clinical virus with a defect in an NK cell-evasion function and exemplifies issues that confront the virus when adapting to immunogenetic diversity in the host.
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