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Fasoulis R, Rigo MM, Lizée G, Antunes DA, Kavraki LE. APE-Gen2.0: Expanding Rapid Class I Peptide-Major Histocompatibility Complex Modeling to Post-Translational Modifications and Noncanonical Peptide Geometries. J Chem Inf Model 2024; 64:1730-1750. [PMID: 38415656 PMCID: PMC10936522 DOI: 10.1021/acs.jcim.3c01667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 02/14/2024] [Accepted: 02/15/2024] [Indexed: 02/29/2024]
Abstract
The recognition of peptides bound to class I major histocompatibility complex (MHC-I) receptors by T-cell receptors (TCRs) is a determinant of triggering the adaptive immune response. While the exact molecular features that drive the TCR recognition are still unknown, studies have suggested that the geometry of the joint peptide-MHC (pMHC) structure plays an important role. As such, there is a definite need for methods and tools that accurately predict the structure of the peptide bound to the MHC-I receptor. In the past few years, many pMHC structural modeling tools have emerged that provide high-quality modeled structures in the general case. However, there are numerous instances of non-canonical cases in the immunopeptidome that the majority of pMHC modeling tools do not attend to, most notably, peptides that exhibit non-standard amino acids and post-translational modifications (PTMs) or peptides that assume non-canonical geometries in the MHC binding cleft. Such chemical and structural properties have been shown to be present in neoantigens; therefore, accurate structural modeling of these instances can be vital for cancer immunotherapy. To this end, we have developed APE-Gen2.0, a tool that improves upon its predecessor and other pMHC modeling tools, both in terms of modeling accuracy and the available modeling range of non-canonical peptide cases. Some of the improvements include (i) the ability to model peptides that have different types of PTMs such as phosphorylation, nitration, and citrullination; (ii) a new and improved anchor identification routine in order to identify and model peptides that exhibit a non-canonical anchor conformation; and (iii) a web server that provides a platform for easy and accessible pMHC modeling. We further show that structures predicted by APE-Gen2.0 can be used to assess the effects that PTMs have in binding affinity in a more accurate manner than just using solely the sequence of the peptide. APE-Gen2.0 is freely available at https://apegen.kavrakilab.org.
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Affiliation(s)
- Romanos Fasoulis
- Department
of Computer Science, Rice University, Houston, Texas 77005, United States
| | - Mauricio M. Rigo
- Department
of Computer Science, Rice University, Houston, Texas 77005, United States
| | - Gregory Lizée
- Department
of Melanoma Medical Oncology—Research, The University of Texas MD Anderson Cancer Center, Houston, Texas 77054, United States
| | - Dinler A. Antunes
- Department
of Biology and Biochemistry, University
of Houston, Houston, Texas 77004, United States
| | - Lydia E. Kavraki
- Department
of Computer Science, Rice University, Houston, Texas 77005, United States
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2
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Sharma T, Kundu N, Kaur S, Shankaraswamy J, Saxena S. Why to target G-quadruplexes using peptides: Next-generation G4-interacting ligands. J Pept Sci 2023; 29:e3491. [PMID: 37009771 DOI: 10.1002/psc.3491] [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: 11/18/2022] [Revised: 03/28/2023] [Accepted: 03/29/2023] [Indexed: 04/04/2023]
Abstract
Guanine-rich oligonucleotides existing in both DNA and RNA are able to fold into four-stranded DNA secondary structures via Hoogsteen type hydrogen-bonding, where four guanines self-assemble into a square planar arrangement, which, when stacked upon each other, results in the formation of higher-order structures called G-quadruplexes. Their distribution is not random; they are more frequently present at telomeres, proto-oncogenic promoters, introns, 5'- and 3'-untranslated regions, stem cell markers, ribosome binding sites and so forth and are associated with various biological functions, all of which play a pivotal role in various incurable diseases like cancer and cellular ageing. Several studies have suggested that G-quadruplexes could not regulate biological processes by themselves; instead, various proteins take part in this regulation and can be important therapeutic targets. There are certain limitations in using whole G4-protein for therapeutics purpose because of its high manufacturing cost, laborious structure prediction, dynamic nature, unavailability for oral administration due to its degradation in the gut and inefficient penetration to reach the target site because of the large size. Hence, biologically active peptides can be the potential candidates for therapeutic intervention instead of the whole G4-protein complex. In this review, we aimed to clarify the biological roles of G4s, how we can identify them throughout the genome via bioinformatics, the proteins interacting with G4s and how G4-interacting peptide molecules may be the potential next-generation ligands for targeting the G4 motifs located in biologically important regions.
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Affiliation(s)
- Taniya Sharma
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Noida, India
| | - Nikita Kundu
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Noida, India
| | - Sarvpreet Kaur
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Noida, India
| | - Jadala Shankaraswamy
- Department of Fruit Science, College of Horticulture, Mojerla, Sri Konda Laxman Telangana State Horticultural University, Budwel, Telangana, India
| | - Sarika Saxena
- Amity Institute of Biotechnology, Amity University Uttar Pradesh, Noida, India
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3
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T. RR, Smith JC. Structural patterns in class 1 major histocompatibility complex‐restricted nonamer peptide binding to T‐cell receptors. Proteins 2022; 90:1645-1654. [DOI: 10.1002/prot.26343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 03/12/2022] [Accepted: 03/27/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Rajitha Rajeshwar T.
- Department of Biochemistry and Cellular and Molecular Biology University of Tennessee Knoxville Tennessee USA
- UT/ORNL Center for Molecular Biophysics Oak Ridge National Laboratory Oak Ridge Tennessee USA
| | - Jeremy C. Smith
- Department of Biochemistry and Cellular and Molecular Biology University of Tennessee Knoxville Tennessee USA
- UT/ORNL Center for Molecular Biophysics Oak Ridge National Laboratory Oak Ridge Tennessee USA
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4
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Simister PC, Border EC, Vieira JF, Pumphrey NJ. Structural insights into engineering a T-cell receptor targeting MAGE-A10 with higher affinity and specificity for cancer immunotherapy. J Immunother Cancer 2022; 10:jitc-2022-004600. [PMID: 35851311 PMCID: PMC9295655 DOI: 10.1136/jitc-2022-004600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND T-cell receptor (TCR) immunotherapy is becoming a viable modality in cancer treatment with efficacy in clinical trials. The safety of patients is paramount, so innovative cell engineering methods are being employed to exploit adaptive immunity while controlling the factors governing antigen receptor (ie, TCR) specificity and cross-reactivity. We recently reported a TCR engineering campaign and selectivity profiling assay (X-scan) targeting a melanoma antigen gene (MAGE)-A10 peptide. This helped to distinguish between two well-performing TCRs based on cross-reactivity potential during preclinical drug evaluation, allowing one to be advanced to T-cell immunotherapeutic clinical trials. Here, we present three-dimensional structural information on those TCRs, highlighting engineering improvements and molecular mechanisms likely underpinning differential selectivity. METHODS Parental and engineered TCRs were purified and crystallized either alone or complexed to human leucocyte antigen (HLA)-A*02:01 presenting the MAGE-A10 9-mer peptide, GLYDGMEHL (pHLA/MAGE-A10-9). Using X-ray diffraction, we solved four high-resolution crystal structures and evaluated them relative to previously reported functional results. RESULTS The unligated parental TCR displayed similar complementarity-determining region (CDR) loop conformations when bound to pHLA/MAGE-A10-9; a rigid-body movement of TCR beta chain variable domain (TRBV) relative to TCR alpha chain variable domain helped optimal pHLA engagement. This first view of an HLA-bound MAGE-A10 peptide revealed an intrachain non-covalent 'staple' between peptide Tyr3 and Glu7. A subtle Glu31-Asp mutation in βCDR1 of the parental TCR generated a high-affinity derivative. Its pHLA-complexed structure shows that the shorter Asp leans toward the pHLA with resulting rigid-body TRBV shift, creating localized changes around the peptide's C-terminus. Structural comparison with a less selective TCR indicated that differential cross-reactivity to MAGE-A10 peptide variants is most readily explained by alterations in surface electrostatics, and the size and geometry of TCR-peptide interfacial cavities. CONCLUSIONS Modest changes in engineered TCRs targeting MAGE-A10 produced significantly different properties. Conformational invariance of TCR and antigen peptide plus more space-filling CDR loop sequences may be desirable properties for clinically relevant TCR-pHLA systems to reduce the likelihood of structurally similar peptide mimics being tolerated by a TCR. Such properties may partially explain why the affinity-enhanced, in vitro-selected TCR has been generally well tolerated in patients.
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5
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Hopkins JR, MacLachlan BJ, Harper S, Sewell AK, Cole DK. Unconventional modes of peptide-HLA-I presentation change the rules of TCR engagement. DISCOVERY IMMUNOLOGY 2022; 1:kyac001. [PMID: 38566908 PMCID: PMC10917088 DOI: 10.1093/discim/kyac001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/18/2022] [Accepted: 04/06/2022] [Indexed: 04/04/2024]
Abstract
The intracellular proteome of virtually every nucleated cell in the body is continuously presented at the cell surface via the human leukocyte antigen class I (HLA-I) antigen processing pathway. This pathway classically involves proteasomal degradation of intracellular proteins into short peptides that can be presented by HLA-I molecules for interrogation by T-cell receptors (TCRs) expressed on the surface of CD8+ T cells. During the initiation of a T-cell immune response, the TCR acts as the T cell's primary sensor, using flexible loops to mould around the surface of the pHLA-I molecule to identify foreign or dysregulated antigens. Recent findings demonstrate that pHLA-I molecules can also be highly flexible and dynamic, altering their shape according to minor polymorphisms between different HLA-I alleles, or interactions with different peptides. These flexible presentation modes have important biological consequences that can, for example, explain why some HLA-I alleles offer greater protection against HIV, or why some cancer vaccine approaches have been ineffective. This review explores how these recent findings redefine the rules for peptide presentation by HLA-I molecules and extend our understanding of the molecular mechanisms that govern TCR-mediated antigen discrimination.
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Affiliation(s)
- Jade R Hopkins
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Bruce J MacLachlan
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | | | - Andrew K Sewell
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - David K Cole
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
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6
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Immunoinformatics-based characterization of immunogenic CD8 T-cell epitopes for a broad-spectrum cell-mediated immunity against high-risk human papillomavirus infection. Microb Pathog 2022; 165:105462. [DOI: 10.1016/j.micpath.2022.105462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/23/2022] [Accepted: 02/24/2022] [Indexed: 12/24/2022]
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7
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T cells targeted to TdT kill leukemic lymphoblasts while sparing normal lymphocytes. Nat Biotechnol 2022; 40:488-498. [PMID: 34873326 PMCID: PMC9005346 DOI: 10.1038/s41587-021-01089-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 09/02/2021] [Indexed: 02/07/2023]
Abstract
Unlike chimeric antigen receptors, T-cell receptors (TCRs) can recognize intracellular targets presented on human leukocyte antigen (HLA) molecules. Here we demonstrate that T cells expressing TCRs specific for peptides from the intracellular lymphoid-specific enzyme terminal deoxynucleotidyl transferase (TdT), presented in the context of HLA-A*02:01, specifically eliminate primary acute lymphoblastic leukemia (ALL) cells of T- and B-cell origin in vitro and in three mouse models of disseminated B-ALL. By contrast, the treatment spares normal peripheral T- and B-cell repertoires and normal myeloid cells in vitro, and in vivo in humanized mice. TdT is an attractive cancer target as it is highly and homogeneously expressed in 80-94% of B- and T-ALLs, but only transiently expressed during normal lymphoid differentiation, limiting on-target toxicity of TdT-specific T cells. TCR-modified T cells targeting TdT may be a promising immunotherapy for B-ALL and T-ALL that preserves normal lymphocytes.
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8
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CD8 coreceptor-mediated focusing can reorder the agonist hierarchy of peptide ligands recognized via the T cell receptor. Proc Natl Acad Sci U S A 2021; 118:2019639118. [PMID: 34272276 PMCID: PMC8307375 DOI: 10.1073/pnas.2019639118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
CD8+ T cells are inherently cross-reactive and recognize numerous peptide antigens in the context of a given major histocompatibility complex class I (MHCI) molecule via the clonotypically expressed T cell receptor (TCR). The lineally expressed coreceptor CD8 interacts coordinately with MHCI at a distinct and largely invariant site to slow the TCR/peptide-MHCI (pMHCI) dissociation rate and enhance antigen sensitivity. However, this biological effect is not necessarily uniform, and theoretical models suggest that antigen sensitivity can be modulated in a differential manner by CD8. We used two intrinsically controlled systems to determine how the relationship between the TCR/pMHCI interaction and the pMHCI/CD8 interaction affects the functional sensitivity of antigen recognition. Our data show that modulation of the pMHCI/CD8 interaction can reorder the agonist hierarchy of peptide ligands across a spectrum of affinities for the TCR.
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9
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Robinson RA, McMurran C, McCully ML, Cole DK. Engineering soluble T-cell receptors for therapy. FEBS J 2021; 288:6159-6173. [PMID: 33624424 PMCID: PMC8596704 DOI: 10.1111/febs.15780] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 02/11/2021] [Accepted: 02/22/2021] [Indexed: 12/15/2022]
Abstract
Immunotherapy approaches that target peptide-human leukocyte antigen (pHLA) complexes are becoming highly attractive because of their potential to access virtually all foreign and cellular proteins. For this reason, there has been considerable interest in the development of the natural ligand for pHLA, the T-cell receptor (TCR), as a soluble drug to target disease-associated pHLA presented at the cell surface. However, native TCR stability is suboptimal for soluble drug development, and natural TCRs generally have weak affinities for pHLAs, limiting their potential to reach efficacious receptor occupancy levels as soluble drugs. To overcome these limitations and make full use of the TCR as a soluble drug platform, several protein engineering solutions have been applied to TCRs to enhance both their stability and affinity, with a focus on retaining target specificity and selectivity. Here, we review these advances and look to the future for the next generation of soluble TCR-based therapies that can target monomorphic HLA-like proteins presenting both peptide and nonpeptide antigens.
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10
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Holland CJ, Crean RM, Pentier JM, de Wet B, Lloyd A, Srikannathasan V, Lissin N, Lloyd KA, Blicher TH, Conroy PJ, Hock M, Pengelly RJ, Spinner TE, Cameron B, Potter EA, Jeyanthan A, Molloy PE, Sami M, Aleksic M, Liddy N, Robinson RA, Harper S, Lepore M, Pudney CR, van der Kamp MW, Rizkallah PJ, Jakobsen BK, Vuidepot A, Cole DK. Specificity of bispecific T cell receptors and antibodies targeting peptide-HLA. J Clin Invest 2021; 130:2673-2688. [PMID: 32310221 DOI: 10.1172/jci130562] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 02/11/2020] [Indexed: 01/09/2023] Open
Abstract
Tumor-associated peptide-human leukocyte antigen complexes (pHLAs) represent the largest pool of cell surface-expressed cancer-specific epitopes, making them attractive targets for cancer therapies. Soluble bispecific molecules that incorporate an anti-CD3 effector function are being developed to redirect T cells against these targets using 2 different approaches. The first achieves pHLA recognition via affinity-enhanced versions of natural TCRs (e.g., immune-mobilizing monoclonal T cell receptors against cancer [ImmTAC] molecules), whereas the second harnesses an antibody-based format (TCR-mimic antibodies). For both classes of reagent, target specificity is vital, considering the vast universe of potential pHLA molecules that can be presented on healthy cells. Here, we made use of structural, biochemical, and computational approaches to investigate the molecular rules underpinning the reactivity patterns of pHLA-targeting bispecifics. We demonstrate that affinity-enhanced TCRs engage pHLA using a comparatively broad and balanced energetic footprint, with interactions distributed over several HLA and peptide side chains. As ImmTAC molecules, these TCRs also retained a greater degree of pHLA selectivity, with less off-target activity in cellular assays. Conversely, TCR-mimic antibodies tended to exhibit binding modes focused more toward hot spots on the HLA surface and exhibited a greater degree of crossreactivity. Our findings extend our understanding of the basic principles that underpin pHLA selectivity and exemplify a number of molecular approaches that can be used to probe the specificity of pHLA-targeting molecules, aiding the development of future reagents.
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Affiliation(s)
| | - Rory M Crean
- Department of Biology and Biochemistry and.,Doctoral Training Centre in Sustainable Chemical Technologies, University of Bath, Bath, United Kingdom
| | | | - Ben de Wet
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | | | - Katy A Lloyd
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | - Paul J Conroy
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | - Miriam Hock
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | - Brian Cameron
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | | | - Malkit Sami
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | - Milos Aleksic
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | | | - Marco Lepore
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom
| | | | | | - Pierre J Rizkallah
- Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
| | | | | | - David K Cole
- Immunocore Ltd., Milton Park, Abingdon, United Kingdom.,Cardiff University School of Medicine, Heath Park, Cardiff, United Kingdom
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11
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TCR Recognition of Peptide-MHC-I: Rule Makers and Breakers. Int J Mol Sci 2020; 22:ijms22010068. [PMID: 33374673 PMCID: PMC7793522 DOI: 10.3390/ijms22010068] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 12/16/2020] [Accepted: 12/21/2020] [Indexed: 12/15/2022] Open
Abstract
T cells are a critical part of the adaptive immune system that are able to distinguish between healthy and unhealthy cells. Upon recognition of protein fragments (peptides), activated T cells will contribute to the immune response and help clear infection. The major histocompatibility complex (MHC) molecules, or human leukocyte antigens (HLA) in humans, bind these peptides to present them to T cells that recognise them with their surface T cell receptors (TCR). This recognition event is the first step that leads to T cell activation, and in turn can dictate disease outcomes. The visualisation of TCR interaction with pMHC using structural biology has been crucial in understanding this key event, unravelling the parameters that drive this interaction and their impact on the immune response. The last five years has been the most productive within the field, wherein half of current unique TCR-pMHC-I structures to date were determined within this time. Here, we review the new insights learned from these recent TCR-pMHC-I structures and their impact on T cell activation.
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12
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Crean RM, MacLachlan BJ, Madura F, Whalley T, Rizkallah PJ, Holland CJ, McMurran C, Harper S, Godkin A, Sewell AK, Pudney CR, van der Kamp MW, Cole DK. Molecular Rules Underpinning Enhanced Affinity Binding of Human T Cell Receptors Engineered for Immunotherapy. Mol Ther Oncolytics 2020; 18:443-456. [PMID: 32913893 PMCID: PMC7452143 DOI: 10.1016/j.omto.2020.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 07/27/2020] [Indexed: 10/25/2022] Open
Abstract
Immuno-oncology approaches that utilize T cell receptors (TCRs) are becoming highly attractive because of their potential to target virtually all cellular proteins, including cancer-specific epitopes, via the recognition of peptide-human leukocyte antigen (pHLA) complexes presented at the cell surface. However, because natural TCRs generally recognize cancer-derived pHLAs with very weak affinities, efforts have been made to enhance their binding strength, in some cases by several million-fold. In this study, we investigated the mechanisms underpinning human TCR affinity enhancement by comparing the crystal structures of engineered enhanced affinity TCRs with those of their wild-type progenitors. Additionally, we performed molecular dynamics simulations to better understand the energetic mechanisms driving the affinity enhancements. These data demonstrate that supra-physiological binding affinities can be achieved without altering native TCR-pHLA binding modes via relatively subtle modifications to the interface contacts, often driven through the addition of buried hydrophobic residues. Individual energetic components of the TCR-pHLA interaction governing affinity enhancements were distinct and highly variable for each TCR, often resulting from additive, or knock-on, effects beyond the mutated residues. This comprehensive analysis of affinity-enhanced TCRs has important implications for the future rational design of engineered TCRs as efficacious and safe drugs for cancer treatment.
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Affiliation(s)
- Rory M. Crean
- Department of Biology and Biochemistry, University of Bath, Bath, BA2 7AY, UK
- Doctoral Training Centre in Sustainable Chemical Technologies, University of Bath, Bath, BA2 7AY, UK
| | | | - Florian Madura
- Division of Infection & Immunity, Cardiff University, Cardiff, CF14 4XN, UK
| | - Thomas Whalley
- Division of Infection & Immunity, Cardiff University, Cardiff, CF14 4XN, UK
| | | | | | | | | | - Andrew Godkin
- Division of Infection & Immunity, Cardiff University, Cardiff, CF14 4XN, UK
| | - Andrew K. Sewell
- Division of Infection & Immunity, Cardiff University, Cardiff, CF14 4XN, UK
| | - Christopher R. Pudney
- Department of Biology and Biochemistry, University of Bath, Bath, BA2 7AY, UK
- Centre for Therapeutic Innovation, University of Bath, Bath, BA2 7AY, UK
| | - Marc W. van der Kamp
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK
| | - David K. Cole
- Division of Infection & Immunity, Cardiff University, Cardiff, CF14 4XN, UK
- Immunocore, Ltd., Abingdon, OX14 4RY, UK
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13
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Coles CH, McMurran C, Lloyd A, Hock M, Hibbert L, Raman MCC, Hayes C, Lupardus P, Cole DK, Harper S. T cell receptor interactions with human leukocyte antigen govern indirect peptide selectivity for the cancer testis antigen MAGE-A4. J Biol Chem 2020; 295:11486-11494. [PMID: 32532817 PMCID: PMC7450119 DOI: 10.1074/jbc.ra120.014016] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/11/2020] [Indexed: 12/18/2022] Open
Abstract
T cell-mediated immunity is governed primarily by T cell receptor (TCR) recognition of peptide-human leukocyte antigen (pHLA) complexes and is essential for immunosurveillance and disease control. This interaction is generally stabilized by interactions between the HLA surface and TCR germline-encoded complementarity-determining region (CDR) loops 1 and 2, whereas peptide selectivity is guided by direct interactions with the TCR CDR3 loops. Here, we solved the structure of a newly identified TCR in complex with a clinically relevant peptide derived from the cancer testis antigen melanoma antigen-A4 (MAGE-A4). The TCR bound pHLA in a position shifted toward the peptide's N terminus. This enabled the TCR to achieve peptide selectivity via an indirect mechanism, whereby the TCR sensed the first residue of the peptide through HLA residue Trp-167, which acted as a tunable gateway. Amino acid substitutions at peptide position 1 predicted to alter the HLA Trp-167 side-chain conformation abrogated TCR binding, indicating that this indirect binding mechanism is essential for peptide recognition. These findings extend our understanding of the molecular rules that underpin antigen recognition by TCRs and have important implications for the development of TCR-based therapies.
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Affiliation(s)
| | | | | | | | | | | | | | | | - David K Cole
- Immunocore Ltd., Abingdon, United Kingdom .,Cardiff University School of Medicine, Cardiff, United Kingdom
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14
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Hopkins JR, Crean RM, Catici DAM, Sewell AK, Arcus VL, Van der Kamp MW, Cole DK, Pudney CR. Peptide cargo tunes a network of correlated motions in human leucocyte antigens. FEBS J 2020; 287:3777-3793. [PMID: 32134551 PMCID: PMC8651013 DOI: 10.1111/febs.15278] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 02/20/2020] [Accepted: 03/03/2020] [Indexed: 11/28/2022]
Abstract
Most biomolecular interactions are typically thought to increase the (local) rigidity of a complex, for example, in drug‐target binding. However, detailed analysis of specific biomolecular complexes can reveal a more subtle interplay between binding and rigidity. Here, we focussed on the human leucocyte antigen (HLA), which plays a crucial role in the adaptive immune system by presenting peptides for recognition by the αβ T‐cell receptor (TCR). The role that the peptide plays in tuning HLA flexibility during TCR recognition is potentially crucial in determining the functional outcome of an immune response, with obvious relevance to the growing list of immunotherapies that target the T‐cell compartment. We have applied high‐pressure/temperature perturbation experiments, combined with molecular dynamics simulations, to explore the drivers that affect molecular flexibility for a series of different peptide–HLA complexes. We find that different peptide sequences affect peptide–HLA flexibility in different ways, with the peptide cargo tuning a network of correlated motions throughout the pHLA complex, including in areas remote from the peptide‐binding interface, in a manner that could influence T‐cell antigen discrimination.
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Affiliation(s)
- Jade R Hopkins
- Division of Infection and Immunity, School of Medicine, Cardiff University, UK
| | - Rory M Crean
- Department of Biology and Biochemistry, University of Bath, UK.,Doctoral Training Centre in Sustainable Chemical Technologies, University of Bath, UK
| | | | - Andrew K Sewell
- Division of Infection and Immunity, School of Medicine, Cardiff University, UK
| | - Vickery L Arcus
- School of Science, Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | | | - David K Cole
- Division of Infection and Immunity, School of Medicine, Cardiff University, UK
| | - Christopher R Pudney
- Department of Biology and Biochemistry, University of Bath, UK.,Centre for Therapeutic Innovation, University of Bath, UK
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15
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Bentzen AK, Hadrup SR. T-cell-receptor cross-recognition and strategies to select safe T-cell receptors for clinical translation. IMMUNO-ONCOLOGY AND TECHNOLOGY 2019; 2:1-10. [PMID: 35036898 PMCID: PMC8741623 DOI: 10.1016/j.iotech.2019.06.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Adoptive transfer of T-cell-receptor (TCR)-transduced T cells has shown promising results for cancer treatment, but has also produced severe immunotoxicities caused by on-target as well as off-target TCR recognition. Off-target toxicities are related to the ability of a single T cell to cross-recognize and respond to several different peptide–major histocompatibility complex (pMHC) antigens; a property that is essential for providing broad antigenic coverage despite a confined number of unique TCRs in the human body. However, this degeneracy makes it incredibly difficult to account for the range of targets that any TCR might recognize, which represents a major challenge for the clinical development of therapeutic TCRs. The prospect of using affinity-optimized TCRs has been impeded due to observations that affinity enhancement might alter the specificity of a TCR, thereby increasing the risk that it will cross-recognize endogenous tissue. Strategies for selecting safe TCRs for the clinic have included functional assessment after individual incubations with tissue-derived primary cells or with peptides substituted with single amino acids. However, these strategies have not been able to predict cross-recognition sufficiently, leading to fatal cross-reactivity in clinical trials. Novel technologies have emerged that enable extensive characterization of the exact interaction points of a TCR with pMHC, which provides a foundation from which to make predictions of the cross-recognition potential of individual TCRs. This review describes current advances in strategies for dissecting the molecular interaction points of TCRs, focusing on their potential as tools for predicting cross-recognition of TCRs in clinical development. T-cell-receptor (TCR) degeneracy plays a fundamental role in the capacity of our immune systems to recognize foreign antigens. TCR cross-reactivity provides an inherent risk in TCR–gene transfer cell therapies. Advances in description of TCR cross-recognition can guide the selection process for TCRs into clinical use.
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16
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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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17
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Border EC, Sanderson JP, Weissensteiner T, Gerry AB, Pumphrey NJ. Affinity-enhanced T-cell receptors for adoptive T-cell therapy targeting MAGE-A10: strategy for selection of an optimal candidate. Oncoimmunology 2018; 8:e1532759. [PMID: 30713784 PMCID: PMC6343776 DOI: 10.1080/2162402x.2018.1532759] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/24/2018] [Accepted: 08/30/2018] [Indexed: 12/12/2022] Open
Abstract
Circulating T-cells that have passed thymic selection generally bear T-cell receptors (TCRs) with sub-optimal affinity for cancer-associated antigens, resulting in a limited ability to detect and eliminate tumor cells. Engineering TCRs to increase their affinity for cancer targets is a promising strategy for generating T-cells with enhanced potency for adoptive immunotherapy in cancer patients. However, this manipulation also risks generating cross-reactivity to antigens expressed by normal tissue, with potentially serious consequences. Testing in animal models might not detect such cross-reactivity due to species differences in the antigenic repertoire. To mitigate the risk of off-target toxicities in future clinical trials, we therefore developed an extensive in vitro testing strategy. This approach involved systematic substitution at each position of the antigenic peptide sequence using all natural amino acids to generate a profile of peptide specificity (“X-scan”). The likelihood of off-target reactivity was investigated by searching the human proteome for sequences matching this profile, and testing against a panel of primary cell lines. Starting from a diverse panel of parental TCRs, we engineered several affinity-enhanced TCRs specific for the cancer-testis antigen MAGE-A10. Two of these TCRs had affinities and specificities which appeared to be equally optimal when tested in conventional biochemical and cellular assays. The X-scan method, however, permitted us to select the most specific and potent candidate for further pre-clinical and clinical testing.
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18
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Dolton G, Zervoudi E, Rius C, Wall A, Thomas HL, Fuller A, Yeo L, Legut M, Wheeler S, Attaf M, Chudakov DM, Choy E, Peakman M, Sewell AK. Optimized Peptide-MHC Multimer Protocols for Detection and Isolation of Autoimmune T-Cells. Front Immunol 2018; 9:1378. [PMID: 30008714 PMCID: PMC6034003 DOI: 10.3389/fimmu.2018.01378] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 06/04/2018] [Indexed: 12/14/2022] Open
Abstract
Peptide–MHC (pMHC) multimers have become the “gold standard” for the detection and isolation of antigen-specific T-cells but recent evidence shows that normal use of these reagents can miss fully functional T-cells that bear T-cell receptors (TCRs) with low affinity for cognate antigen. This issue is particularly pronounced for anticancer and autoimmune T-cells as self-reactive T-cell populations are enriched for low-affinity TCRs due to the removal of cells with higher affinity receptors by immune tolerance mechanisms. Here, we stained a wide variety of self-reactive human T-cells using regular pMHC staining and an optimized technique that included: (i) protein kinase inhibitor (PKI), to prevent TCR triggering and internalization, and (ii) anti-fluorochrome antibody, to reduce reagent dissociation during washing steps. Lymphocytes derived from the peripheral blood of type 1 diabetes patients were stained with pMHC multimers made with epitopes from preproinsulin (PPI), insulin-β chain, glutamic acid decarboxylase 65 (GAD65), or glucose-6-phospate catalytic subunit-related protein (IGRP) presented by disease-risk allelles HLA A*02:01 or HLA*24:02. Samples from ankylosing spondylitis patients were stained with a multimerized epitope from vasoactive intestinal polypeptide receptor 1 (VIPR1) presented by HLA B*27:05. Optimized procedures stained an average of 40.5-fold (p = 0.01, range between 1.4 and 198) more cells than could be detected without the inclusion of PKI and cross-linking anti-fluorochrome antibody. Higher order pMHC dextramers recovered more cells than pMHC tetramers in parallel assays, and standard staining protocols with pMHC tetramers routinely recovered less cells than functional assays. HLA A*02:01-restricted PPI-specific and HLA B*27:05-restricted VIPR1-specific T-cell clones generated using the optimized procedure could not be stained by standard pMHC tetramer staining. However, these clones responded well to exogenously supplied peptide and endogenously processed and presented epitopes. We also showed that anti-fluorochrome antibody-conjugated magnetic beads enhanced staining of self-reactive T-cells that could not be stained using standard protocols, thus enabling rapid ex vivo isolation of autoimmune T-cells. We, therefore, conclude that regular pMHC tetramer staining is generally unsuitable for recovering self-reactive T-cells from clinical samples and recommend the use of the optimized protocols described herein.
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Affiliation(s)
- Garry Dolton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Efthalia Zervoudi
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Cristina Rius
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Aaron Wall
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Hannah L Thomas
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Anna Fuller
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Lorraine Yeo
- Department of Immunobiology, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, London, United Kingdom
| | - Mateusz Legut
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Sophie Wheeler
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Meriem Attaf
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Dmitriy M Chudakov
- Pirogov Russian National Research Medical University, Moscow, Russia.,Centre for Data-Intensive Biomedicine and Biotechnology, Skolkovo Institute of Science and Technology, Skolkovo, Russia.,Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russia
| | - Ernest Choy
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom.,Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Mark Peakman
- Department of Immunobiology, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, London, United Kingdom
| | - Andrew K Sewell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, United Kingdom.,Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
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19
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Holland CJ, MacLachlan BJ, Bianchi V, Hesketh SJ, Morgan R, Vickery O, Bulek AM, Fuller A, Godkin A, Sewell AK, Rizkallah PJ, Wells S, Cole DK. In Silico and Structural Analyses Demonstrate That Intrinsic Protein Motions Guide T Cell Receptor Complementarity Determining Region Loop Flexibility. Front Immunol 2018; 9:674. [PMID: 29696015 PMCID: PMC5904202 DOI: 10.3389/fimmu.2018.00674] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 03/19/2018] [Indexed: 11/13/2022] Open
Abstract
T-cell immunity is controlled by T cell receptor (TCR) binding to peptide major histocompatibility complexes (pMHCs). The nature of the interaction between these two proteins has been the subject of many investigations because of its central role in immunity against pathogens, cancer, in autoimmunity, and during organ transplant rejection. Crystal structures comparing unbound and pMHC-bound TCRs have revealed flexibility at the interaction interface, particularly from the perspective of the TCR. However, crystal structures represent only a snapshot of protein conformation that could be influenced through biologically irrelevant crystal lattice contacts and other factors. Here, we solved the structures of three unbound TCRs from multiple crystals. Superposition of identical TCR structures from different crystals revealed some conformation differences of up to 5 Å in individual complementarity determining region (CDR) loops that are similar to those that have previously been attributed to antigen engagement. We then used a combination of rigidity analysis and simulations of protein motion to reveal the theoretical potential of TCR CDR loop flexibility in unbound state. These simulations of protein motion support the notion that crystal structures may only offer an artifactual indication of TCR flexibility, influenced by crystallization conditions and crystal packing that is inconsistent with the theoretical potential of intrinsic TCR motions.
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Affiliation(s)
- Christopher J Holland
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Immunocore, Abingdon, United Kingdom
| | - Bruce J MacLachlan
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Valentina Bianchi
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Department of Oncology, University Hospital of Lausanne, Lausanne, Switzerland
| | - Sophie J Hesketh
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Richard Morgan
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Owen Vickery
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Anna M Bulek
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Anna Fuller
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Andrew Godkin
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Andrew K Sewell
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Pierre J Rizkallah
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Stephen Wells
- Department of Chemistry, University of Bath, Bath, United Kingdom
| | - David K Cole
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Cardiff, United Kingdom.,Immunocore, Abingdon, United Kingdom
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20
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Curtidor H, Reyes C, Bermúdez A, Vanegas M, Varela Y, Patarroyo ME. Conserved Binding Regions Provide the Clue for Peptide-Based Vaccine Development: A Chemical Perspective. Molecules 2017; 22:molecules22122199. [PMID: 29231862 PMCID: PMC6149789 DOI: 10.3390/molecules22122199] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 11/24/2017] [Accepted: 11/27/2017] [Indexed: 12/17/2022] Open
Abstract
Synthetic peptides have become invaluable biomedical research and medicinal chemistry tools for studying functional roles, i.e., binding or proteolytic activity, naturally-occurring regions’ immunogenicity in proteins and developing therapeutic agents and vaccines. Synthetic peptides can mimic protein sites; their structure and function can be easily modulated by specific amino acid replacement. They have major advantages, i.e., they are cheap, easily-produced and chemically stable, lack infectious and secondary adverse reactions and can induce immune responses via T- and B-cell epitopes. Our group has previously shown that using synthetic peptides and adopting a functional approach has led to identifying Plasmodium falciparumconserved regions binding to host cells. Conserved high activity binding peptides’ (cHABPs) physicochemical, structural and immunological characteristics have been taken into account for properly modifying and converting them into highly immunogenic, protection-inducing peptides (mHABPs) in the experimental Aotus monkey model. This article describes stereo–electron and topochemical characteristics regarding major histocompatibility complex (MHC)-mHABP-T-cell receptor (TCR) complex formation. Some mHABPs in this complex inducing long-lasting, protective immunity have been named immune protection-inducing protein structures (IMPIPS), forming the subunit components in chemically synthesized vaccines. This manuscript summarizes this particular field and adds our recent findings concerning intramolecular interactions (H-bonds or π-interactions) enabling proper IMPIPS structure as well as the peripheral flanking residues (PFR) to stabilize the MHCII-IMPIPS-TCR interaction, aimed at inducing long-lasting, protective immunological memory.
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Affiliation(s)
- Hernando Curtidor
- Colombian Institute of Immunology Foundation (FIDIC Nonprofit-Making Organisation), Bogotá 111321, Colombia.
- School of Medicine and Health Sciences, University of Rosario, Bogotá 111321, Colombia.
| | - César Reyes
- Colombian Institute of Immunology Foundation (FIDIC Nonprofit-Making Organisation), Bogotá 111321, Colombia.
| | - Adriana Bermúdez
- Colombian Institute of Immunology Foundation (FIDIC Nonprofit-Making Organisation), Bogotá 111321, Colombia.
- School of Medicine and Health Sciences, University of Rosario, Bogotá 111321, Colombia.
| | - Magnolia Vanegas
- Colombian Institute of Immunology Foundation (FIDIC Nonprofit-Making Organisation), Bogotá 111321, Colombia.
- School of Medicine and Health Sciences, University of Rosario, Bogotá 111321, Colombia.
| | - Yahson Varela
- Colombian Institute of Immunology Foundation (FIDIC Nonprofit-Making Organisation), Bogotá 111321, Colombia.
- Faculty of Health Sciences, Applied and Environmental Sciences University (UDCA), Bogotá 111321, Colombia.
| | - Manuel E Patarroyo
- Colombian Institute of Immunology Foundation (FIDIC Nonprofit-Making Organisation), Bogotá 111321, Colombia.
- Faculty of Medicine, National University of Colombia, Bogotá 111321, Colombia.
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21
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Fuller A, Wall A, Crowther MD, Lloyd A, Zhurov A, Sewell AK, Cole DK, Beck K. Thermal Stability of Heterotrimeric pMHC Proteins as Determined by Circular Dichroism Spectroscopy. Bio Protoc 2017; 7:e2366. [PMID: 28748203 DOI: 10.21769/bioprotoc.2366] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
T cell receptor (TCR) recognition of foreign peptide fragments, presented by peptide major histocompatibility complex (pMHC), governs T-cell mediated protection against pathogens and cancer. Many factors govern T-cell sensitivity, including the affinity of the TCR-pMHC interaction and the stability of pMHC on the surface of antigen presenting cells. These factors are particularly relevant for the peptide vaccination field, in which more stable pMHC interactions could enable more effective protection against disease. Here, we discuss a method for the determination of pMHC stability that we have used to investigate HIV immune escape, T-cell sensitivity to cancer antigens and mechanisms leading to autoimmunity.
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Affiliation(s)
- Anna Fuller
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Aaron Wall
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Michael D Crowther
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Angharad Lloyd
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Alexei Zhurov
- Cardiff University School of Dentistry, Heath Park, Cardiff, UK
| | - Andrew K Sewell
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - David K Cole
- Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Konrad Beck
- Cardiff University School of Dentistry, Heath Park, Cardiff, UK
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