1
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Dolton G, Rius C, Wall A, Szomolay B, Bianchi V, Galloway SAE, Hasan MS, Morin T, Caillaud ME, Thomas HL, Theaker S, Tan LR, Fuller A, Topley K, Legut M, Attaf M, Hopkins JR, Behiry E, Zabkiewicz J, Alvares C, Lloyd A, Rogers A, Henley P, Fegan C, Ottmann O, Man S, Crowther MD, Donia M, Svane IM, Cole DK, Brown PE, Rizkallah P, Sewell AK. Targeting of multiple tumor-associated antigens by individual T cell receptors during successful cancer immunotherapy. Cell 2023; 186:3333-3349.e27. [PMID: 37490916 DOI: 10.1016/j.cell.2023.06.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 04/20/2023] [Accepted: 06/24/2023] [Indexed: 07/27/2023]
Abstract
The T cells of the immune system can target tumors and clear solid cancers following tumor-infiltrating lymphocyte (TIL) therapy. We used combinatorial peptide libraries and a proteomic database to reveal the antigen specificities of persistent cancer-specific T cell receptors (TCRs) following successful TIL therapy for stage IV malignant melanoma. Remarkably, individual TCRs could target multiple different tumor types via the HLA A∗02:01-restricted epitopes EAAGIGILTV, LLLGIGILVL, and NLSALGIFST from Melan A, BST2, and IMP2, respectively. Atomic structures of a TCR bound to all three antigens revealed the importance of the shared x-x-x-A/G-I/L-G-I-x-x-x recognition motif. Multi-epitope targeting allows individual T cells to attack cancer in several ways simultaneously. Such "multipronged" T cells exhibited superior recognition of cancer cells compared with conventional T cell recognition of individual epitopes, making them attractive candidates for the development of future immunotherapies.
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Affiliation(s)
- Garry Dolton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Cristina Rius
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Aaron Wall
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Barbara Szomolay
- Systems Immunology Research Institute, Cardiff, Wales CF14 4XN, UK
| | - Valentina Bianchi
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Sarah A E Galloway
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Md Samiul Hasan
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Théo Morin
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Marine E Caillaud
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Hannah L Thomas
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Sarah Theaker
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Li Rong Tan
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Anna Fuller
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Katie Topley
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Mateusz Legut
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Meriem Attaf
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Jade R Hopkins
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Enas Behiry
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Joanna Zabkiewicz
- Division of Cancer and Genetics, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Caroline Alvares
- Division of Cancer and Genetics, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Angharad Lloyd
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Amber Rogers
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Peter Henley
- Division of Cancer and Genetics, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Christopher Fegan
- Division of Cancer and Genetics, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Oliver Ottmann
- Division of Cancer and Genetics, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Stephen Man
- Division of Cancer and Genetics, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Michael D Crowther
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK; National Center for Cancer Immune Therapy, Department of Oncology, Copenhagen University Hospital, Herlev, Denmark
| | - Marco Donia
- National Center for Cancer Immune Therapy, Department of Oncology, Copenhagen University Hospital, Herlev, Denmark
| | - Inge Marie Svane
- National Center for Cancer Immune Therapy, Department of Oncology, Copenhagen University Hospital, Herlev, Denmark
| | - David K Cole
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Paul E Brown
- The Zeeman Institute, University of Warwick, Coventry CV4 7AL, UK
| | - Pierre Rizkallah
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK
| | - Andrew K Sewell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, Wales CF14 4XN, UK; Systems Immunology Research Institute, Cardiff, Wales CF14 4XN, UK.
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2
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Dolton G, Rius C, Hasan MS, Wall A, Szomolay B, Behiry E, Whalley T, Southgate J, Fuller A, Morin T, Topley K, Tan LR, Goulder PJR, Spiller OB, Rizkallah PJ, Jones LC, Connor TR, Sewell AK. Emergence of immune escape at dominant SARS-CoV-2 killer T cell epitope. Cell 2022; 185:2936-2951.e19. [PMID: 35931021 PMCID: PMC9279490 DOI: 10.1016/j.cell.2022.07.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 05/08/2022] [Accepted: 07/07/2022] [Indexed: 01/06/2023]
Abstract
We studied the prevalent cytotoxic CD8 T cell response mounted against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike glycoprotein269-277 epitope (sequence YLQPRTFLL) via the most frequent human leukocyte antigen (HLA) class I worldwide, HLA A∗02. The Spike P272L mutation that has arisen in at least 112 different SARS-CoV-2 lineages to date, including in lineages classified as "variants of concern," was not recognized by the large CD8 T cell response seen across cohorts of HLA A∗02+ convalescent patients and individuals vaccinated against SARS-CoV-2, despite these responses comprising of over 175 different individual T cell receptors. Viral escape at prevalent T cell epitopes restricted by high frequency HLAs may be particularly problematic when vaccine immunity is focused on a single protein such as SARS-CoV-2 Spike, providing a strong argument for inclusion of multiple viral proteins in next generation vaccines and highlighting the need for monitoring T cell escape in new SARS-CoV-2 variants.
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Affiliation(s)
- Garry Dolton
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Cristina Rius
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Md Samiul Hasan
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Aaron Wall
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Barbara Szomolay
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK; Systems Immunology Research Institute, Cardiff University, CF14 4XN Cardiff, Wales, UK
| | - Enas Behiry
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Thomas Whalley
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, Wales, UK
| | - Joel Southgate
- School of Biosciences, Cardiff University, CF10 3AX Cardiff, Wales, UK
| | - Anna Fuller
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Théo Morin
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Katie Topley
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Li Rong Tan
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Philip J R Goulder
- Department of Paediatrics, University of Oxford, OX3 9DU Oxford, England, UK
| | - Owen B Spiller
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Pierre J Rizkallah
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK
| | - Lucy C Jones
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK; Centre for Clinical Research, Royal Glamorgan Hospital, Ynysmaerdy CF72 8XR, UK
| | - Thomas R Connor
- Systems Immunology Research Institute, Cardiff University, CF14 4XN Cardiff, Wales, UK; School of Biosciences, Cardiff University, CF10 3AX Cardiff, Wales, UK; Pathogen genomics Unit, Public Health Wales NHS Trust, CF14 4XW Cardiff, Wales, UK.
| | - Andrew K Sewell
- Division of Infection and Immunity, Cardiff University School of Medicine, CF14 4XN Cardiff, Wales, UK; Systems Immunology Research Institute, Cardiff University, CF14 4XN Cardiff, Wales, UK.
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3
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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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4
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Engineering the T cell receptor for fun and profit: Uncovering complex biology, interrogating the immune system, and targeting disease. Curr Opin Struct Biol 2022; 74:102358. [PMID: 35344834 DOI: 10.1016/j.sbi.2022.102358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/13/2022] [Accepted: 02/21/2022] [Indexed: 11/21/2022]
Abstract
T cell receptors (TCRs) orchestrate cellular immunity by recognizing peptide antigens bound and presented by major histocompatibility complex (MHC) proteins. Due to the TCR's central role in immunity and tight connection with human health, there has been significant interest in modulating TCR properties through protein engineering methods. Complicating these efforts is the complexity and vast diversity of TCR-peptide/MHC interfaces, the interdependency between TCR affinity, specificity, and cross-reactivity, and the sophisticated relationships between TCR binding properties and T cell function, many aspects of which are not well understood. Here we review TCR engineering, starting with a brief historical overview followed by discussions of more recent developments, including new efforts and opportunities to engineer TCR affinity, modulate specificity, and develop novel TCR-based constructs.
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5
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FACS-Based Functional Protein Screening via Microfluidic Co-encapsulation of Yeast Secretor and Mammalian Reporter Cells. Sci Rep 2020; 10:10182. [PMID: 32576855 PMCID: PMC7311539 DOI: 10.1038/s41598-020-66927-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 05/20/2020] [Indexed: 12/22/2022] Open
Abstract
In this study, we present a straightforward approach for functional cell-based screening by co-encapsulation of secretor yeast cells and reporter mammalian cells in millions of individual agarose-containing microdroplets. Our system is compatible with ultra-high-throughput selection utilizing standard fluorescence-activated cell sorters (FACS) without need of extensive adaptation and optimization. In a model study we co-encapsulated murine interleukin 3 (mIL-3)-secreting S. cerevisiae cells with murine Ba/F3 reporter cells, which express green fluorescent protein (GFP) upon stimulation with mIL-3, and could observe specific and robust induction of fluorescence signal compared to a control with yeast cells secreting a non-functional mIL-3 mutant. We demonstrate the successful enrichment of activating mIL-3 wt-secreting yeast cells from a 1:10,000 dilution in cells expressing the inactive cytokine variant by two consecutive cycles of co-encapsulation and FACS. This indicates the suitability of the presented strategy for functional screening of high-diversity yeast-based libraries and demonstrates its potential for the efficient isolation of clones secreting bioactive recombinant proteins.
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6
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Whalley T, Dolton G, Brown PE, Wall A, Wooldridge L, van den Berg H, Fuller A, Hopkins JR, Crowther MD, Attaf M, Knight RR, Cole DK, Peakman M, Sewell AK, Szomolay B. GPU-Accelerated Discovery of Pathogen-Derived Molecular Mimics of a T-Cell Insulin Epitope. Front Immunol 2020; 11:296. [PMID: 32184781 PMCID: PMC7058665 DOI: 10.3389/fimmu.2020.00296] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 02/05/2020] [Indexed: 01/09/2023] Open
Abstract
The strong links between (Human Leukocyte Antigen) HLA, infection and autoimmunity combine to implicate T-cells as primary triggers of autoimmune disease (AD). T-cell crossreactivity between microbially-derived peptides and self-peptides has been shown to break tolerance and trigger AD in experimental animal models. Detailed examination of the potential for T-cell crossreactivity to trigger human AD will require means of predicting which peptides might be recognised by autoimmune T-cell receptors (TCRs). Recent developments in high throughput sequencing and bioinformatics mean that it is now possible to link individual TCRs to specific pathologies for the first time. Deconvolution of TCR function requires knowledge of TCR specificity. Positional Scanning Combinatorial Peptide Libraries (PS-CPLs) can be used to predict HLA-restriction and define antigenic peptides derived from self and pathogen proteins. In silico search of the known terrestrial proteome with a prediction algorithm that ranks potential antigens in order of recognition likelihood requires complex, large-scale computations over several days that are infeasible on a personal computer. We decreased the time required for peptide searching to under 30 min using multiple blocks on graphics processing units (GPUs). This time-efficient, cost-effective hardware accelerator was used to screen bacterial and fungal human pathogens for peptide sequences predicted to activate a T-cell clone, InsB4, that was isolated from a patient with type 1 diabetes and recognised the insulin B-derived epitope HLVEALYLV in the context of disease-risk allele HLA A*0201. InsB4 was shown to kill HLA A*0201+ human insulin producing β-cells demonstrating that T-cells with this specificity might contribute to disease. The GPU-accelerated algorithm and multispecies pathogen proteomic databases were validated to discover pathogen-derived peptide sequences that acted as super-agonists for the InsB4 T-cell clone. Peptide-MHC tetramer binding and surface plasmon resonance were used to confirm that the InsB4 TCR bound to the highest-ranked peptide agonists derived from infectious bacteria and fungi. Adoption of GPU-accelerated prediction of T-cell agonists has the capacity to revolutionise our understanding of AD by identifying potential targets for autoimmune T-cells. This approach has further potential for dissecting T-cell responses to infectious disease and cancer.
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Affiliation(s)
- Thomas Whalley
- Cardiff University School of Medicine, Cardiff, United Kingdom.,Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Garry Dolton
- Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Paul E Brown
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, University of Warwick Coventry, Coventry, United Kingdom
| | - Aaron Wall
- Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Linda Wooldridge
- Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom
| | - Hugo van den Berg
- Mathematics Institute, University of Warwick, Coventry, United Kingdom
| | - Anna Fuller
- Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Jade R Hopkins
- Cardiff University School of Medicine, Cardiff, United Kingdom
| | | | - Meriem Attaf
- Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Robin R Knight
- Peter Gorer Department of Immunobiology, Guy's Hospital, London, United Kingdom
| | - David K Cole
- Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Mark Peakman
- Peter Gorer Department of Immunobiology, Guy's Hospital, London, United Kingdom
| | - Andrew K Sewell
- Cardiff University School of Medicine, Cardiff, United Kingdom.,Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
| | - Barbara Szomolay
- Cardiff University School of Medicine, Cardiff, United Kingdom.,Systems Immunity Research Institute, Cardiff University, Cardiff, United Kingdom
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7
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Tripathi SK, Salunke DM. Exploring the different states of wild-type T-cell receptor and mutant conformational changes towards understanding the antigen recognition. J Biomol Struct Dyn 2020; 39:188-201. [PMID: 31870204 DOI: 10.1080/07391102.2019.1708795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Recognition of proteolytic peptide fragments presented by major histocompatibility complex (MHC) on target cells by T-cell receptor (TCR) is among the most important interactions in the adaptive immune system. Several computational studies have been performed to investigate conformational and dynamical properties of TCRs for enhanced immunogenicity. Here, we present the large-scale molecular dynamics (MD) simulation studies of the two comprehensive systems consisting of the wild-type and mutant IG4 TCR in complex with the tumor epitope NY-ESO peptide (SLLMWITQC) and analyzed for mapping conformational changes of TCR in the states prior to antigen binding, upon antigen binding and after the antigen was released. All of the simulations were performed with different states of TCRs for each 1000 ns of simulation time, providing six simulations for time duration of 6000 ns (6µs). We show that rather than undergoing most critical conformational changes upon antigen binding, the high proportion of complementarity-determining region (CDR) loops change by comparatively small amount. The hypervariable CDRα3 and CDRβ3 loops showed significant structural changes. Interestingly, the TCR β chain loops showed the least changes, which is reliable with recent implications that β domain of TCR may propel antigen interaction. The mutant shows higher rigidity than wild-type even in released state; expose an induced fit mechanism occurring from the re-structuring of CDRα3 loop and can allow enhanced binding affinity of the peptide antigen. Additionally, we show that CDRα3 loop and peptide contacts are an adaptive feature of affinity enhanced mutant TCR.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Sunil Kumar Tripathi
- Structural Immunology Group, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India
| | - Dinakar M Salunke
- Structural Immunology Group, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India.,Structural Immunology Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
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8
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Sádio F, Stadlmayr G, Stadlbauer K, Gräf M, Scharrer A, Rüker F, Wozniak-Knopp G. Stabilization of soluble high-affinity T-cell receptor with de novo disulfide bonds. FEBS Lett 2019; 594:477-490. [PMID: 31552676 PMCID: PMC7027902 DOI: 10.1002/1873-3468.13616] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 09/04/2019] [Accepted: 09/17/2019] [Indexed: 12/12/2022]
Abstract
Soluble T‐cell receptors (TCRs) have recently gained visibility as target‐recognition units of anticancer immunotherapeutic agents. Here, we improved the thermal stability of the well‐expressed high‐affinity A6 TCR by introducing pairs of cysteines in the invariable parts of the α‐ and β‐chain. A mutant with a novel intradomain disulfide bond in each chain also tested superior to the wild‐type in the accelerated stability assay. Binding of the mutant to the soluble cognate peptide (cp)–MHC and to the peptide‐loaded T2 cell line was equal to the wild‐type A6 TCR. The same stabilization motif worked efficiently in TCRs with different specificities, such as DMF5 and 1G4. Altogether, the biophysical properties of the soluble TCR molecule could be improved, without affecting its expression level and antigen‐binding specificity.
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Affiliation(s)
- Flávio Sádio
- Christian Doppler Laboratory for Innovative Immunotherapeutics, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Gerhard Stadlmayr
- Christian Doppler Laboratory for Innovative Immunotherapeutics, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Katharina Stadlbauer
- Christian Doppler Laboratory for Innovative Immunotherapeutics, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Maximilian Gräf
- Christian Doppler Laboratory for Innovative Immunotherapeutics, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Agnes Scharrer
- Christian Doppler Laboratory for Innovative Immunotherapeutics, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Florian Rüker
- Christian Doppler Laboratory for Innovative Immunotherapeutics, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Gordana Wozniak-Knopp
- Christian Doppler Laboratory for Innovative Immunotherapeutics, Department of Biotechnology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
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9
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Targeting the MHC Ligandome by Use of TCR-Like Antibodies. Antibodies (Basel) 2019; 8:antib8020032. [PMID: 31544838 PMCID: PMC6640717 DOI: 10.3390/antib8020032] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 12/11/2022] Open
Abstract
Monoclonal antibodies (mAbs) are valuable as research reagents, in diagnosis and in therapy. Their high specificity, the ease in production, favorable biophysical properties and the opportunity to engineer different properties make mAbs a versatile class of biologics. mAbs targeting peptide–major histocompatibility molecule (pMHC) complexes are often referred to as “TCR-like” mAbs, as pMHC complexes are generally recognized by T-cell receptors (TCRs). Presentation of self- and non-self-derived peptide fragments on MHC molecules and subsequent activation of T cells dictate immune responses in health and disease. This includes responses to infectious agents or cancer but also aberrant responses against harmless self-peptides in autoimmune diseases. The ability of TCR-like mAbs to target specific peptides presented on MHC allows for their use to study peptide presentation or for diagnosis and therapy. This extends the scope of conventional mAbs, which are generally limited to cell-surface or soluble antigens. Herein, we review the strategies used to generate TCR-like mAbs and provide a structural comparison with the analogous TCR in pMHC binding. We further discuss their applications as research tools and therapeutic reagents in preclinical models as well as challenges and limitations associated with their use.
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10
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Watanabe K, Tsukahara T, Toji S, Saitoh S, Hirohashi Y, Nakatsugawa M, Kubo T, Kanaseki T, Kameshima H, Terui T, Sato N, Torigoe T. Development of a T-cell receptor multimer with high avidity for detecting a naturally presented tumor-associated antigen on osteosarcoma cells. Cancer Sci 2018; 110:40-51. [PMID: 30375705 PMCID: PMC6317924 DOI: 10.1111/cas.13854] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 10/25/2018] [Accepted: 10/26/2018] [Indexed: 11/28/2022] Open
Abstract
For efficacy of peptide vaccination immunotherapy for patients with cancer, endogenous expression of the target peptide/human leukocyte antigen (HLA) on cancer cells is required. However, it is difficult to evaluate the expression status of a peptide/HLA complex because of the lack of a soluble T‐cell receptor (TCR) that reacts with tumor‐associated antigen (TAA) with high avidity. In the present study, we developed two soluble TCR‐multimers that were each directed to TAA, survivin‐2B (SVN‐2B) and PBF in the context of HLA‐A24 (SVN‐2B TCR‐multimer and PBF TCR‐multimer, respectively), from CTL clones that were established from peptide‐vaccinated patients. Both TCR multimers could recognize cognate peptide‐pulsed antigen‐presenting cells, C1R‐A24 cells, in a CD8‐independent method. Moreover, the PBF TCR‐multimer successfully recognized a PBF peptide naturally presented on HLA‐A24+PBF+ osteosarcoma cells. Taken together, the results indicated that a TCR‐multimer might be useful for detection of a TAA‐derived peptide presented by HLA in patients receiving immunotherapy.
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Affiliation(s)
- Kazue Watanabe
- Department of Cancer Immunology, Medical and Biological Laboratories Co., Ltd, Ina, Japan.,Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Tomohide Tsukahara
- Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Shingo Toji
- Department of Cancer Immunology, Medical and Biological Laboratories Co., Ltd, Ina, Japan
| | - Shogo Saitoh
- Department of Cancer Immunology, Medical and Biological Laboratories Co., Ltd, Ina, Japan
| | - Yoshihiko Hirohashi
- Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Munehide Nakatsugawa
- Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Terufumi Kubo
- Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Takayuki Kanaseki
- Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | | | | | - Noriyuki Sato
- Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan.,Higashi-Sapporo Hospital, Sapporo, Japan
| | - Toshihiko Torigoe
- Department of Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
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11
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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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12
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Identification of the cognate peptide-MHC target of T cell receptors using molecular modeling and force field scoring. Mol Immunol 2017; 94:91-97. [PMID: 29288899 DOI: 10.1016/j.molimm.2017.12.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/27/2017] [Accepted: 12/20/2017] [Indexed: 11/22/2022]
Abstract
Interactions of T cell receptors (TCR) to peptides in complex with MHC (p:MHC) are key features that mediate cellular immune responses. While MHC binding is required for a peptide to be presented to T cells, not all MHC binders are immunogenic. The interaction of a TCR to the p:MHC complex holds a key, but currently poorly comprehended, component for our understanding of this variation in the immunogenicity of MHC binding peptides. Here, we demonstrate that identification of the cognate target of a TCR from a set of p:MHC complexes to a high degree is achievable using simple force-field energy terms. Building a benchmark of TCR:p:MHC complexes where epitopes and non-epitopes are modelled using state-of-the-art molecular modelling tools, scoring p:MHC to a given TCR using force-fields, optimized in a cross-validation setup to evaluate TCR inter atomic interactions involved with each p:MHC, we demonstrate that this approach can successfully be used to distinguish between epitopes and non-epitopes. A detailed analysis of the performance of this force-field-based approach demonstrate that its predictive performance depend on the ability to both accurately predict the binding of the peptide to the MHC and model the TCR:p:MHC complex structure. In summary, we conclude that it is possible to identify the TCR cognate target among different candidate peptides by using a force-field based model, and believe this works could lay the foundation for future work within prediction of TCR:p:MHC interactions.
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13
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Cole DK, Fuller A, Dolton G, Zervoudi E, Legut M, Miles K, Blanchfield L, Madura F, Holland CJ, Bulek AM, Bridgeman JS, Miles JJ, Schauenburg AJA, Beck K, Evavold BD, Rizkallah PJ, Sewell AK. Dual Molecular Mechanisms Govern Escape at Immunodominant HLA A2-Restricted HIV Epitope. Front Immunol 2017; 8:1503. [PMID: 29209312 PMCID: PMC5701626 DOI: 10.3389/fimmu.2017.01503] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 10/25/2017] [Indexed: 12/05/2022] Open
Abstract
Serial accumulation of mutations to fixation in the SLYNTVATL (SL9) immunodominant, HIV p17 Gag-derived, HLA A2-restricted cytotoxic T lymphocyte epitope produce the SLFNTIAVL triple mutant “ultimate” escape variant. These mutations in solvent-exposed residues are believed to interfere with TCR recognition, although confirmation has awaited structural verification. Here, we solved a TCR co-complex structure with SL9 and the triple escape mutant to determine the mechanism of immune escape in this eminent system. We show that, in contrast to prevailing hypotheses, the main TCR contact residue is 4N and the dominant mechanism of escape is not via lack of TCR engagement. Instead, mutation of solvent-exposed residues in the peptide destabilise the peptide–HLA and reduce peptide density at the cell surface. These results highlight the extraordinary lengths that HIV employs to evade detection by high-affinity TCRs with a broad peptide-binding footprint and necessitate re-evaluation of this exemplar model of HIV TCR escape.
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Affiliation(s)
- David K Cole
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Anna Fuller
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Garry Dolton
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Efthalia Zervoudi
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Mateusz Legut
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Kim Miles
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Lori Blanchfield
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, United States
| | - Florian Madura
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Christopher J Holland
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Anna M Bulek
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - John S Bridgeman
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - John J Miles
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom.,James Cook University, Cairns, QLD, Australia
| | - Andrea J A Schauenburg
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Konrad Beck
- Cardiff University School of Dentistry, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Brian D Evavold
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, United States
| | - Pierre J Rizkallah
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
| | - Andrew K Sewell
- Cardiff University School of Medicine, University Hospital, Heath Park, Cardiff, United Kingdom
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14
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Preparation of peptide-MHC and T-cell receptor dextramers by biotinylated dextran doping. Biotechniques 2017; 62:123-130. [PMID: 28298179 DOI: 10.2144/000114525] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 01/25/2017] [Indexed: 11/23/2022] Open
Abstract
Peptide-major histocompatibility complex (pMHC) multimers enable the detection, characterization, and isolation of antigen-specific T-cell subsets at the single-cell level via flow cytometry and fluorescence microscopy. These labeling reagents exploit a multivalent scaffold to increase the avidity of individually weak T-cell receptor (TCR)-pMHC interactions. Dextramers are an improvement over the original streptavidin-based tetramer technology because they are more multivalent, improving sensitivity for rare, low-avidity T cells, including self/tumor-reactive clones. However, commercial pMHC dextramers are expensive, and in-house production is very involved for a typical biology research laboratory. Here, we present a simple, inexpensive protocol for preparing pMHC dextramers by doping in biotinylated dextran during conventional tetramer preparation. We use these pMHC dextramers to identify patient-derived, tumor-reactive T cells. We apply the same dextran doping technique to prepare TCR dextramers and use these novel reagents to yield new insight into MHC I-mediated antigen presentation.
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15
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Pawlak JB, Hos BJ, van de Graaff MJ, Megantari OA, Meeuwenoord N, Overkleeft HS, Filippov DV, Ossendorp F, van Kasteren SI. The Optimization of Bioorthogonal Epitope Ligation within MHC-I Complexes. ACS Chem Biol 2016; 11:3172-3178. [PMID: 27704768 DOI: 10.1021/acschembio.6b00498] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Antigen recognition followed by the activation of cytotoxic T-cells (CTLs) is a key step in adaptive immunity, resulting in clearance of viruses and cancers. The repertoire of peptides that have the ability to bind to the major histocompatibility type-I (MHC-I) is enormous, but the approaches available for studying the diversity of the peptide repertoire on a cell are limited. Here, we explore the use of bioorthogonal chemistry to quantify specific peptide-MHC-I complexes (pMHC-I) on cells. We show that modifying epitope peptides with bioorthogonal groups in surface accessible positions allows wild-type-like MHC-I binding and bioorthogonal ligation using fluorogenic chromophores in combination with a Cu(I)-catalyzed Huisgen cycloaddition reaction. We expect that this approach will make a powerful addition to the antigen presentation toolkit as for the first time it allows quantification of antigenic peptides for which no detection tools exist.
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Affiliation(s)
- Joanna B. Pawlak
- Leiden
Institute of Chemistry and The Institute for Chemical Immunology, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Brett J. Hos
- Department
of Immunohematology and Blood Transfusion, Leiden University Medical Center and The Institute for Chemical Immunology, P.O. Box 9600, 2300 RC Leiden, The Netherlands
| | - Michel J. van de Graaff
- Leiden
Institute of Chemistry and The Institute for Chemical Immunology, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Otty A. Megantari
- Leiden
Institute of Chemistry and The Institute for Chemical Immunology, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Nico Meeuwenoord
- Leiden
Institute of Chemistry and The Institute for Chemical Immunology, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Herman S. Overkleeft
- Leiden
Institute of Chemistry and The Institute for Chemical Immunology, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Dmitri V. Filippov
- Leiden
Institute of Chemistry and The Institute for Chemical Immunology, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Ferry Ossendorp
- Department
of Immunohematology and Blood Transfusion, Leiden University Medical Center and The Institute for Chemical Immunology, P.O. Box 9600, 2300 RC Leiden, The Netherlands
| | - Sander I. van Kasteren
- Leiden
Institute of Chemistry and The Institute for Chemical Immunology, Leiden University Einsteinweg 55, 2333 CC Leiden, The Netherlands
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16
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Nakatsugawa M, Rahman MA, Yamashita Y, Ochi T, Wnuk P, Tanaka S, Chamoto K, Kagoya Y, Saso K, Guo T, Anczurowski M, Butler MO, Hirano N. CD4(+) and CD8(+) TCRβ repertoires possess different potentials to generate extraordinarily high-avidity T cells. Sci Rep 2016; 6:23821. [PMID: 27030642 PMCID: PMC4814874 DOI: 10.1038/srep23821] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/15/2016] [Indexed: 12/31/2022] Open
Abstract
Recent high throughput sequencing analysis has revealed that the TCRβ repertoire is largely different between CD8(+) and CD4(+) T cells. Here, we show that the transduction of SIG35α, the public chain-centric HLA-A*02:01(A2)/MART127-35 TCRα hemichain, conferred A2/MART127-35 reactivity to a substantial subset of both CD8(+) and CD4(+) T cells regardless of their HLA-A2 positivity. T cells individually reconstituted with SIG35α and different A2/MART127-35 TCRβ genes isolated from CD4(+) or CD8(+) T cells exhibited a wide range of avidity. Surprisingly, approximately half of the A2/MART127-35 TCRs derived from CD4(+) T cells, but none from CD8(+) T cells, were stained by A2/MART127-35 monomer and possessed broader cross-reactivity. Our results suggest that the differences in the primary structure of peripheral CD4(+) and CD8(+) TCRβ repertoire indeed result in the differences in their ability to form extraordinarily high avidity T cells which would otherwise have been deleted by central tolerance.
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Affiliation(s)
- Munehide Nakatsugawa
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Muhammed A. Rahman
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Yuki Yamashita
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Toshiki Ochi
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Piotr Wnuk
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
- Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Shinya Tanaka
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
- Takara Bio, Inc., Kusatsu, Shiga 525-0058, Japan
| | - Kenji Chamoto
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Yuki Kagoya
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Kayoko Saso
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Tingxi Guo
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
- Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Mark Anczurowski
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
- Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Marcus O. Butler
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
- Department of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Naoto Hirano
- Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Campbell Family Cancer Research Institute, Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
- Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
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17
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Holland CJ, Dolton G, Scurr M, Ladell K, Schauenburg AJ, Miners K, Madura F, Sewell AK, Price DA, Cole DK, Godkin AJ. Enhanced Detection of Antigen-Specific CD4+ T Cells Using Altered Peptide Flanking Residue Peptide-MHC Class II Multimers. THE JOURNAL OF IMMUNOLOGY 2015; 195:5827-36. [PMID: 26553072 PMCID: PMC4671089 DOI: 10.4049/jimmunol.1402787] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 10/08/2015] [Indexed: 11/22/2022]
Abstract
Fluorochrome-conjugated peptide–MHC (pMHC) class I multimers are staple components of the immunologist’s toolbox, enabling reliable quantification and analysis of Ag-specific CD8+ T cells irrespective of functional outputs. In contrast, widespread use of the equivalent pMHC class II (pMHC-II) reagents has been hindered by intrinsically weaker TCR affinities for pMHC-II, a lack of cooperative binding between the TCR and CD4 coreceptor, and a low frequency of Ag-specific CD4+ T cell populations in the peripheral blood. In this study, we show that peptide flanking regions, extending beyond the central nonamer core of MHC-II–bound peptides, can enhance TCR–pMHC-II binding and T cell activation without loss of specificity. Consistent with these findings, pMHC-II multimers incorporating peptide flanking residue modifications proved superior for the ex vivo detection, characterization, and manipulation of Ag-specific CD4+ T cells, highlighting an unappreciated feature of TCR–pMHC-II interactions.
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Affiliation(s)
- Christopher J Holland
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Garry Dolton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Martin Scurr
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Kristin Ladell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Andrea J Schauenburg
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Kelly Miners
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Florian Madura
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Andrew K Sewell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - David A Price
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - David K Cole
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and
| | - Andrew J Godkin
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, Wales, United Kingdom; and Department of Integrated Medicine, University Hospital of Wales, Cardiff CF14 4XW, Wales, United Kingdom
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18
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Tan MP, Gerry AB, Brewer JE, Melchiori L, Bridgeman JS, Bennett AD, Pumphrey NJ, Jakobsen BK, Price DA, Ladell K, Sewell AK. T cell receptor binding affinity governs the functional profile of cancer-specific CD8+ T cells. Clin Exp Immunol 2015; 180:255-70. [PMID: 25496365 PMCID: PMC4408161 DOI: 10.1111/cei.12570] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2014] [Indexed: 12/17/2022] Open
Abstract
Antigen-specific T cell receptor (TCR) gene transfer via patient-derived T cells is an attractive approach to cancer therapy, with the potential to circumvent immune regulatory networks. However, high-affinity tumour-specific TCR clonotypes are typically deleted from the available repertoire during thymic selection because the vast majority of targeted epitopes are derived from autologous proteins. This process places intrinsic constraints on the efficacy of T cell-based cancer vaccines and therapeutic strategies that employ naturally generated tumour-specific TCRs. In this study, we used altered peptide ligands and lentivirus-mediated transduction of affinity-enhanced TCRs selected by phage display to study the functional properties of CD8(+) T cells specific for three different tumour-associated peptide antigens across a range of binding parameters. The key findings were: (i) TCR affinity controls T cell antigen sensitivity and polyfunctionality; (ii) supraphysiological affinity thresholds exist, above which T cell function cannot be improved; and (iii) T cells transduced with very high-affinity TCRs exhibit cross-reactivity with self-derived peptides presented by the restricting human leucocyte antigen. Optimal system-defined affinity windows above the range established for natural tumour-specific TCRs therefore allow the enhancement of T cell effector function without off-target effects. These findings have major implications for the rational design of novel TCR-based biologics underpinned by rigorous preclinical evaluation.
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Affiliation(s)
- M P Tan
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
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19
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Soluble T-cell receptors produced in human cells for targeted delivery. PLoS One 2015; 10:e0119559. [PMID: 25875651 PMCID: PMC4395278 DOI: 10.1371/journal.pone.0119559] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 01/14/2015] [Indexed: 12/15/2022] Open
Abstract
Recently, technology has become available to generate soluble T-cell receptors (sTCRs) that contain the antigen recognition part. In contrast to antibodies, sTCRs recognize intracellular in addition to extracellular epitopes, potentially increasing the number of applications as reagents for target detection and immunotherapy. Moreover, recent data show that they can be used for identification of their natural peptide ligands in disease. Here we describe a new and simplified expression method for sTCRs in human cells and show that these sTCRs can be used for antigen-specific labeling and elimination of human target cells. Four different TCRs were solubilized by expression of constructs encoding the TCR alpha (α) and beta (β) chains lacking the transmembrane and intracellular domains, linked by a ribosomal skipping 2A sequence that facilitates equimolar production of the chains. Cell supernatants containing sTCRs labeled target cells directly in a peptide (p)-human leukocyte antigen (HLA)-specific manner. We demonstrated that a MART-1p/HLA-A*02:01-specific sTCR fused to a fluorescent protein, or multimerized onto magnetic nanoparticles, could be internalized. Moreover, we showed that this sTCR and two sTCRs recognizing CD20p/HLA-A*02:01 could mediate selective elimination of target cells expressing the relevant pHLA complex when tetramerized to streptavidin-conjugated toxin, demonstrating the potential for specific delivery of cargo. This simple and efficient method can be utilized to generate a wide range of minimally modified sTCRs from the naturally occurring TCR repertoire for antigen-specific detection and targeting.
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20
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Løset GÅ, Berntzen G, Frigstad T, Pollmann S, Gunnarsen KS, Sandlie I. Phage Display Engineered T Cell Receptors as Tools for the Study of Tumor Peptide-MHC Interactions. Front Oncol 2015; 4:378. [PMID: 25629004 PMCID: PMC4290511 DOI: 10.3389/fonc.2014.00378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 12/17/2014] [Indexed: 11/13/2022] Open
Abstract
Cancer immunotherapy has finally come of age, demonstrated by recent progress in strategies that engage the endogenous adaptive immune response in tumor killing. Occasionally, significant and durable tumor regression has been achieved. A giant leap forward was the demonstration that the pre-existing polyclonal T cell repertoire could be re-directed by use of cloned T cell receptors (TCRs), to obtain a defined tumor-specific pool of T cells. However, the procedure must be performed with caution to avoid deleterious cross-reactivity. Here, the use of engineered soluble TCRs may represent a safer, yet powerful, alternative. There is also a need for deeper understanding of the processes that underlie antigen presentation in disease and homeostasis, how tumor-specific peptides are generated, and how epitope spreading evolves during tumor development. Due to its plasticity, the pivotal interaction where a TCR engages a peptide/MHC (pMHC) also requires closer attention. For this purpose, phage display as a tool to evolve cloned TCRs represents an attractive avenue to generate suitable reagents allowing the study of defined pMHC presentation, TCR engagement, as well as for the discovery of novel therapeutic leads. Here, we highlight important aspects of the current status in this field.
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Affiliation(s)
- Geir Åge Løset
- Nextera AS , Oslo , Norway ; Centre for Immune Regulation, Oslo University Hospital, University of Oslo , Oslo , Norway ; Department of Biosciences, University of Oslo , Oslo , Norway
| | | | | | | | - Kristin S Gunnarsen
- Centre for Immune Regulation, Oslo University Hospital, University of Oslo , Oslo , Norway
| | - Inger Sandlie
- Centre for Immune Regulation, Oslo University Hospital, University of Oslo , Oslo , Norway ; Department of Biosciences, University of Oslo , Oslo , Norway
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21
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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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22
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The basis for limited specificity and MHC restriction in a T cell receptor interface. Nat Commun 2013; 4:1948. [PMID: 23736024 PMCID: PMC3708045 DOI: 10.1038/ncomms2948] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 04/30/2013] [Indexed: 02/03/2023] Open
Abstract
αβ T cell receptors (TCRs) recognize peptides presented by major histocompatibility complex (MHC) proteins using multiple complementarity determining region (CDR) loops. TCRs display an array of poorly understood recognition properties, including specificity, cross-reactivity, and MHC restriction. Here we report a comprehensive thermodynamic deconstruction of the interaction between the A6 TCR and the Tax peptide presented by the class I MHC HLA-A*0201, uncovering the physical basis for the receptor's recognition properties. Broadly, our findings are in conflict with widely-held generalities regarding TCR recognition, such as the relative contributions of central and peripheral peptide residues and the roles of the hypervariable and germline CDR loops in engaging peptide and MHC. Instead we find that the recognition properties of the receptor emerge from the need to engage the composite peptide/MHC surface, with the receptor utilizing its CDR loops in a cooperative fashion such that specificity, cross-reactivity, and MHC restriction are inextricably linked.
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Cole DK, Miles KM, Madura F, Holland CJ, Schauenburg AJA, Godkin AJ, Bulek AM, Fuller A, Akpovwa HJE, Pymm PG, Liddy N, Sami M, Li Y, Rizkallah PJ, Jakobsen BK, Sewell AK. T-cell receptor (TCR)-peptide specificity overrides affinity-enhancing TCR-major histocompatibility complex interactions. J Biol Chem 2013; 289:628-38. [PMID: 24196962 PMCID: PMC3887192 DOI: 10.1074/jbc.m113.522110] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
αβ T-cell receptors (TCRs) engage antigens using complementarity-determining region (CDR) loops that are either germ line-encoded (CDR1 and CDR2) or somatically rearranged (CDR3). TCR ligands compose a presentation platform (major histocompatibility complex (MHC)) and a variable antigenic component consisting of a short “foreign” peptide. The sequence of events when the TCR engages its peptide-MHC (pMHC) ligand remains unclear. Some studies suggest that the germ line elements of the TCR engage the MHC prior to peptide scanning, but this order of binding is difficult to reconcile with some TCR-pMHC structures. Here, we used TCRs that exhibited enhanced pMHC binding as a result of mutations in either CDR2 and/or CDR3 loops, that bound to the MHC or peptide, respectively, to dissect the roles of these loops in stabilizing TCR-pMHC interactions. Our data show that TCR-peptide interactions play a strongly dominant energetic role providing a binding mode that is both temporally and energetically complementary with a system requiring positive selection by self-pMHC in the thymus and rapid recognition of non-self-pMHC in the periphery.
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Affiliation(s)
- David K Cole
- From Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN
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24
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Cole DK, Sami M, Scott DR, Rizkallah PJ, Borbulevych OY, Todorov PT, Moysey RK, Jakobsen BK, Boulter JM, Baker BM, Yi Li. Increased Peptide Contacts Govern High Affinity Binding of a Modified TCR Whilst Maintaining a Native pMHC Docking Mode. Front Immunol 2013; 4:168. [PMID: 23805144 PMCID: PMC3693486 DOI: 10.3389/fimmu.2013.00168] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 06/12/2013] [Indexed: 12/15/2022] Open
Abstract
Natural T cell receptors (TCRs) generally bind to their cognate pMHC molecules with weak affinity and fast kinetics, limiting their use as therapeutic agents. Using phage display, we have engineered a high affinity version of the A6 wild-type TCR (A6wt), specific for the human leukocyte antigen (HLA-A∗0201) complexed with human T cell lymphotropic virus type 111–19 peptide (A2-Tax). Mutations in just 4 residues in the CDR3β loop region of the A6wt TCR were selected that improved binding to A2-Tax by nearly 1000-fold. Biophysical measurements of this mutant TCR (A6c134) demonstrated that the enhanced binding was derived through favorable enthalpy and a slower off-rate. The structure of the free A6c134 TCR and the A6c134/A2-Tax complex revealed a native binding mode, similar to the A6wt/A2-Tax complex. However, concordant with the more favorable binding enthalpy, the A6c134 TCR made increased contacts with the Tax peptide compared with the A6wt/A2-Tax complex, demonstrating a peptide-focused mechanism for the enhanced affinity that directly involved the mutated residues in the A6c134 TCR CDR3β loop. This peptide-focused enhanced TCR binding may represent an important approach for developing antigen specific high affinity TCR reagents for use in T cell based therapies.
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Affiliation(s)
- David K Cole
- Cardiff University School of Medicine, Heath Park , Cardiff , UK
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25
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Baker BM, Scott DR, Blevins SJ, Hawse WF. Structural and dynamic control of T-cell receptor specificity, cross-reactivity, and binding mechanism. Immunol Rev 2013; 250:10-31. [PMID: 23046120 DOI: 10.1111/j.1600-065x.2012.01165.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Over the past two decades, structural biology has shown how T-cell receptors engage peptide/major histocompatibility complex (MHC) complexes and provided insight into the mechanisms underlying antigen specificity and cross-reactivity. Here we review and contextualize our contributions, which have emphasized the influence of structural changes and molecular flexibility. A repeated observation is the presence of conformational melding, in which the T-cell receptor (TCR), peptide, and in some cases, MHC protein cooperatively adjust in order for recognition to proceed. The structural changes reflect the intrinsic dynamics of the unligated proteins. Characterization of the dynamics of unligated TCR shows how binding loop motion can influence TCR cross-reactivity as well as specificity towards peptide and MHC. Examination of peptide dynamics indicates not only peptide-specific variation but also a peptide dependence to MHC flexibility. This latter point emphasizes that the TCR engages a composite peptide/MHC surface and that physically the receptor makes little distinction between the peptide and MHC. Much additional evidence for this can be found within the database of available structures, including our observations of a peptide dependence to the TCR binding mode and structural compensations for altered interatomic interactions, in which lost TCR-peptide interactions are replaced with TCR-MHC interactions. The lack of a hard-coded physical distinction between peptide and MHC has implications not only for specificity and cross-reactivity but also the mechanisms underlying MHC restriction as well as attempts to modulate and control TCR recognition.
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Affiliation(s)
- Brian M Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, IN, USA.
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26
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Low JL, Naidoo A, Yeo G, Gehring AJ, Ho ZZ, Yau YH, Shochat SG, Kranz DM, Bertoletti A, Grotenbreg GM. Binding of TCR multimers and a TCR-like antibody with distinct fine-specificities is dependent on the surface density of HLA complexes. PLoS One 2012; 7:e51397. [PMID: 23251518 PMCID: PMC3519586 DOI: 10.1371/journal.pone.0051397] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 10/31/2012] [Indexed: 01/02/2023] Open
Abstract
Class I Major Histocompatibility Complex (MHC) molecules evolved to sample degraded protein fragments from the interior of the cell, and to display them at the surface for immune surveillance by CD8+ T cells. The ability of these lymphocytes to identify immunogenic peptide-MHC (pMHC) products on, for example, infected hepatocytes, and to subsequently eliminate those cells, is crucial for the control of hepatitis B virus (HBV). Various protein scaffolds have been designed to recapitulate the specific recognition of presented antigens with the aim to be exploited both diagnostically (e.g. to visualize cells exposed to infectious agents or cellular transformation) and therapeutically (e.g. for the delivery of drugs to compromised cells). In line with this, we report the construction of a soluble tetrameric form of an αβ T cell receptor (TCR) specific for the HBV epitope Env183–191 restricted by HLA-A*02:01, and compare its avidity and fine-specificity with a TCR-like monoclonal antibody generated against the same HLA target. A flow cytometry-based assay with streptavidin-coated beads loaded with Env183–191/HLA-A*02:01 complexes at high surface density, enabled us to probe the specific interaction of these molecules with their cognate pMHC. We demonstrate that the TCR tetramer has similar avidity for the pMHC as the antibody, but they differ in their fine-specificity, with only the TCR tetramer being capable of binding both natural variants of the Env183–191 epitope found in HBV genotypes A/C/D (187Arg) and genotype B (187Lys). Collectively, the results highlight the promiscuity of our soluble TCR, which could be an advantageous feature when targeting cells infected with a mutation-prone virus, but that binding of the soluble oligomeric TCR relies considerably on the surface density of the presented antigen.
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Affiliation(s)
- Jianrong L. Low
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, (A*STAR), Singapore, Singapore
- Department of Biochemistry, University of Illinois at Urbana-Champaign (UIUC), Urbana, Illinois, United States of America
| | - Anneta Naidoo
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, (A*STAR), Singapore, Singapore
| | - Gladys Yeo
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Immunology Programme, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Adam J. Gehring
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, (A*STAR), Singapore, Singapore
| | - Zi Zong Ho
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, (A*STAR), Singapore, Singapore
| | - Yin Hoe Yau
- Nanyang Technological University (NTU), School of Biological Sciences, Singapore, Singapore
| | - Susana G. Shochat
- Nanyang Technological University (NTU), School of Biological Sciences, Singapore, Singapore
| | - David M. Kranz
- Department of Biochemistry, University of Illinois at Urbana-Champaign (UIUC), Urbana, Illinois, United States of America
| | - Antonio Bertoletti
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, (A*STAR), Singapore, Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
| | - Gijsbert M. Grotenbreg
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Department of Biological Sciences, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- Immunology Programme, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, Singapore
- * E-mail:
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27
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Cole DK, Laugel B, Clement M, Price DA, Wooldridge L, Sewell AK. The molecular determinants of CD8 co-receptor function. Immunology 2012; 137:139-48. [PMID: 22804746 DOI: 10.1111/j.1365-2567.2012.03625.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
CD8(+) T cells respond to signals mediated through a specific interaction between the T-cell receptor (TCR) and a composite antigen in the form of an epitopic peptide bound between the polymorphic α1 and α2 helices of an MHC class I (MHCI) molecule. The CD8 glycoprotein 'co-receives' antigen by binding to an invariant region of the MHCI molecule and can enhance ligand recognition by up to 1 million-fold. In recent years, a number of structural and biophysical investigations have shed light on the role of the CD8 co-receptor during T-cell antigen recognition. Here, we provide a collated resource for these data, and discuss how the structural and biophysical parameters governing CD8 co-receptor function further our understanding of T-cell cross-reactivity and the productive engagement of low-affinity antigenic ligands.
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Affiliation(s)
- David K Cole
- Institute of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK.
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28
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Russo V, Bondanza A, Ciceri F, Bregni M, Bordignon C, Traversari C, Bonini C. A dual role for genetically modified lymphocytes in cancer immunotherapy. Trends Mol Med 2012; 18:193-200. [DOI: 10.1016/j.molmed.2011.12.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 12/04/2011] [Accepted: 12/12/2011] [Indexed: 12/18/2022]
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29
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Bridgeman JS, Sewell AK, Miles JJ, Price DA, Cole DK. Structural and biophysical determinants of αβ T-cell antigen recognition. Immunology 2012; 135:9-18. [PMID: 22044041 DOI: 10.1111/j.1365-2567.2011.03515.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The molecular rules that govern MHC restriction, and allow T-cells to differentiate between peptides derived from healthy cells and those from diseased cells, remain poorly understood. Here we provide an overview of the structural constraints that enable the T-cell receptor (TCR) to discriminate between self and non-self peptides, and summarize studies that have attempted to correlate the biophysical parameters of TCR/peptide-major histocompatibility complex (pMHC) binding with T-cell activation. We further review how the antigenic origin of peptide epitopes affects TCR binding parameters and the 'quality' of a T-cell response. Understanding the principles that govern pMHC recognition by T-cells will unlock pathways to the rational development of immunotherapeutic approaches for the treatment of infectious disease, cancer and autoimmunity.
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Affiliation(s)
- John S Bridgeman
- Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, UK
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30
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Laugel B, Cole DK, Clement M, Wooldridge L, Price DA, Sewell AK. The multiple roles of the CD8 coreceptor in T cell biology: opportunities for the selective modulation of self-reactive cytotoxic T cells. J Leukoc Biol 2011; 90:1089-99. [PMID: 21954283 DOI: 10.1189/jlb.0611316] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Short peptide fragments generated by intracellular protein cleavage are presented on the surface of most nucleated cells bound to highly polymorphic MHCI molecules. These pMHCI complexes constitute an interface that allows the immune system to identify and eradicate anomalous cells, such as those that harbor infectious agents, through the activation of CTLs. Molecular recognition of pMHCI complexes is mediated primarily by clonally distributed TCRs expressed on the surface of CTLs. The coreceptor CD8 contributes to this antigen-recognition process by binding to a largely invariant region of the MHCI molecule and by promoting intracellular signaling, the effects of which serve to enhance TCR stimuli triggered by cognate ligands. Recent investigations have shed light on the role of CD8 in the activation of MHCI-restricted, antigen-experienced T cells and in the processes of T cell selection and lineage commitment in the thymus. Here, we review these data and discuss their implications for the development of potential therapeutic strategies that selectively target pathogenic CTL responses erroneously directed against self-derived antigens.
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Affiliation(s)
- Bruno Laugel
- School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN Wales, UK.
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31
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Borbulevych OY, Santhanagopolan SM, Hossain M, Baker BM. TCRs used in cancer gene therapy cross-react with MART-1/Melan-A tumor antigens via distinct mechanisms. THE JOURNAL OF IMMUNOLOGY 2011; 187:2453-63. [PMID: 21795600 DOI: 10.4049/jimmunol.1101268] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
T cells engineered to express TCRs specific for tumor Ags can drive cancer regression. The first TCRs used in cancer gene therapy, DMF4 and DMF5, recognize two structurally distinct peptide epitopes of the melanoma-associated MART-1/Melan-A protein, both presented by the class I MHC protein HLA-A*0201. To help understand the mechanisms of TCR cross-reactivity and provide a foundation for the further development of immunotherapy, we determined the crystallographic structures of DMF4 and DMF5 in complex with both of the MART-1/Melan-A epitopes. The two TCRs use different mechanisms to accommodate the two ligands. Although DMF4 binds the two with a different orientation, altering its position over the peptide/MHC, DMF5 binds them both identically. The simpler mode of cross-reactivity by DMF5 is associated with higher affinity toward both ligands, consistent with the superior functional avidity of DMF5. More generally, the observation of two diverging mechanisms of cross-reactivity with the same Ags and the finding that TCR-binding orientation can be determined by peptide alone extend our understanding of the mechanisms underlying TCR cross-reactivity.
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Affiliation(s)
- Oleg Y Borbulevych
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
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32
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Human T cells expressing affinity-matured TCR display accelerated responses but fail to recognize low density of MHC-peptide antigen. Blood 2011; 118:319-29. [DOI: 10.1182/blood-2010-12-326736] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
We have tested whether affinity-matured TCRs that retain peptide specificity improve the ability of primary human CD8+ T cells to mount antigen-specific responses. We found that TCR affinity correlated with the speed of T-cell responses. High affinity TCR–antigen interactions rapidly initiated T-cell responses, but low affinity TCR/antigen interactions required longer time periods to elicit the same responses. Within the “natural” affinity range, increased TCR-to-antigen affinity correlated with improved ability of T cells to recognize low concentration of antigen. However, affinity-matured TCR with 700-fold enhanced affinity for MHC-to-antigen required 100-fold higher antigen-density to initiate T-cell responses than did wild-type TCR. Using modified peptides to reduce the affinity of TCR-to-antigen interaction, we demonstrate that affinity-matured TCRs are not defective, being superior to wild-type TCR in recognizing low concentration of modified peptides. These data indicate that enhancing TCR affinity can accelerate the speed of T-cell activation and reduce the ability to recognize low density of MHC-to-peptide antigen. We predict that future studies of the human T-cell repertoire will reveal 2 types of low avidity T cells: fast and slow responders, with high-affinity and low-affinity TCR, respectively.
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Borbulevych OY, Piepenbrink KH, Baker BM. Conformational melding permits a conserved binding geometry in TCR recognition of foreign and self molecular mimics. THE JOURNAL OF IMMUNOLOGY 2011; 186:2950-8. [PMID: 21282516 DOI: 10.4049/jimmunol.1003150] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Molecular mimicry between foreign and self Ags is a mechanism of TCR cross-reactivity and is thought to contribute to the development of autoimmunity. The αβ TCR A6 recognizes the foreign Ag Tax from the human T cell leukemia virus-1 when presented by the class I MHC HLA-A2. In a possible link with the autoimmune disease human T cell leukemia virus-1-associated myelopathy/tropical spastic paraparesis, A6 also recognizes a self peptide from the neuronal protein HuD in the context of HLA-A2. We found in our study that the complexes of the HuD and Tax epitopes with HLA-A2 are close but imperfect structural mimics and that in contrast with other recent structures of TCRs with self Ags, A6 engages the HuD Ag with the same traditional binding mode used to engage Tax. Although peptide and MHC conformational changes are needed for recognition of HuD but not Tax and the difference of a single hydroxyl triggers an altered TCR loop conformation, TCR affinity toward HuD is still within the range believed to result in negative selection. Probing further, we found that the HuD-HLA-A2 complex is only weakly stable. Overall, these findings help clarify how molecular mimicry can drive self/nonself cross-reactivity and illustrate how low peptide-MHC stability can permit the survival of T cells expressing self-reactive TCRs that nonetheless bind with a traditional binding mode.
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Affiliation(s)
- Oleg Y Borbulevych
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
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34
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Pierce BG, Haidar JN, Yu Y, Weng Z. Combinations of affinity-enhancing mutations in a T cell receptor reveal highly nonadditive effects within and between complementarity determining regions and chains. Biochemistry 2010; 49:7050-9. [PMID: 20681514 DOI: 10.1021/bi901969a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Understanding the energetic and structural response to multiple mutations in a protein-protein interface is a key aspect of rational protein design. Here we investigate the cooperativity of combinations of point mutations of a T cell receptor (TCR) that binds in vivo to HLA-A2 MHC and a viral peptide. The mutations were obtained from two sources: a structure-based design study on the TCR alpha chain (nine mutations) and an in vitro selection study on the TCR beta chain (four mutations). In addition to combining the highest-affinity variants from each chain, we tested other combinations of mutations within and among the chains, for a total of 23 TCR mutants that we measured for binding kinetics to the peptide and major histocompatibility complex. A wide range of binding affinities was observed, from 2- to 1000-fold binding improvement versus that of the wild type, with significant nonadditive effects observed within and between TCR chains. This included an amino acid-dependent cooperative interaction between CDR1 and CDR3 residues that are separated by more than 9 A in the wild-type complex. When analyzing the kinetics of the mutations, we found that the association rates were primarily responsible for the cooperativity, while the dissociation rates were responsible for the anticooperativity (less-than-additive energetics). On the basis of structural modeling of anticooperative mutants, we determined that side chain clash between proximal mutants likely led to nonadditive binding energies. These results highlight the complex nature of TCR association and binding and will be informative in future design efforts that combine multiple mutant residues.
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Affiliation(s)
- Brian G Pierce
- Bioinformatics Program, Boston University, Boston, Massachusetts 02215, USA
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35
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Sims S, Willberg C, Klenerman P. MHC-peptide tetramers for the analysis of antigen-specific T cells. Expert Rev Vaccines 2010; 9:765-74. [PMID: 20624049 DOI: 10.1586/erv.10.66] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The development of the fluorescently labeled tetrameric MHC-peptide complex has enabled the direct visualization, quantification and phenotypic characterization of antigen-specific T cells using flow cytometry and has transformed our understanding of cellular immune responses. The combination of this technology with functional assays provides many new insights into these cells, allowing investigation into their lifecycle, manner of death and effector function. In this article, we hope to provide an overview of the techniques used in the construction of these tetramers, the problems and solutions associated with them, and the methods used in the study of antigen-specific T cells. Understanding how the antigen-specific cells develop and function in different circumstances and with different pathogens will be key to understanding natural host defense, as well as vaccine design and assessment.
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Affiliation(s)
- Stuart Sims
- Nuffield Department of Medicine and NIHR Biomedical Research Centre, University of Oxford, Oxford, UK.
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36
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Lunde E, Løset GÅ, Bogen B, Sandlie I. Stabilizing mutations increase secretion of functional soluble TCR-Ig fusion proteins. BMC Biotechnol 2010; 10:61. [PMID: 20735812 PMCID: PMC2936418 DOI: 10.1186/1472-6750-10-61] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Accepted: 08/24/2010] [Indexed: 12/02/2022] Open
Abstract
Background Whereas T cell receptors (TCRs) detect peptide/major histocompatibility complexes (pMHCs) with exquisite specificity, there are challenges regarding their expression and use as soluble detection molecules due to molecular instability. We have investigated strategies for the production of TCR-immunoglobulin (Ig) fusion proteins. Two different TCRs that are characteristic of a mouse model for idiotype (Id) dependent immune regulation were engineered. They are structurally unrelated with different variable (V), diversity (D) and joining (J) segments, but each share one V gene segment, either Vα or Vβ, with the well characterized murine TCR, 2C. Results Several TCR-Ig formats were assessed. In one, the TCR V domains were fused to Ig constant (C) regions. In others, the complete extracellular part of the TCR was fused either to a complete Ig or an Ig Fc region. All molecules were initially poorly secreted from eukaryotic cells, but replacement of unfavourable amino acids in the V regions improved secretion, as did the introduction of a disulfide bridge between the TCR C domains and the removal of an unpaired cysteine. A screening strategy for selection of mutations that stabilize the actual fusion molecules was developed and used successfully. Molecules that included the complete heterodimeric TCR, with a stabilizing disulfide bridge, were correctly folded as they bound TCR-specific antibodies (Abs) and detected pMHC on cells after specific peptide loading. Conclusions We show that fully functional TCR-Ig fusion proteins can be made in good yields following stabilizing engineering of TCR V and C region genes. This is important since TCR-Ig fusions will be important probes for the presence of specific pMHCs in vitro and in vivo. In the absence of further affinity maturation, the reagents will be very useful for the detection of kinetic stability of complexes of peptide and MHC.
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Affiliation(s)
- Elin Lunde
- Department of Molecular Biosciences, Centre for Immune Regulation, University of Oslo, Oslo 0316, Norway
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T cell receptor cross-reactivity directed by antigen-dependent tuning of peptide-MHC molecular flexibility. Immunity 2010; 31:885-96. [PMID: 20064447 DOI: 10.1016/j.immuni.2009.11.003] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Revised: 09/21/2009] [Accepted: 11/04/2009] [Indexed: 11/22/2022]
Abstract
T cell-mediated immunity requires T cell receptor (TCR) cross-reactivity, the mechanisms behind which remain incompletely elucidated. The alphabeta TCR A6 recognizes both the Tax (LLFGYPVYV) and Tel1p (MLWGYLQYV) peptides presented by the human class I MHC molecule HLA-A2. Here we found that although the two ligands are ideal structural mimics, they form substantially different interfaces with A6, with conformational differences in the peptide, the TCR, and unexpectedly, the MHC molecule. The differences between the Tax and Tel1p ternary complexes could not be predicted from the free peptide-MHC structures and are inconsistent with a traditional induced-fit mechanism. Instead, the differences were attributable to peptide and MHC molecular motion present in Tel1p-HLA-A2 but absent in Tax-HLA-A2. Differential "tuning" of the dynamic properties of HLA-A2 by the Tax and Tel1p peptides thus facilitates cross-recognition and impacts how structural diversity can be presented to and accommodated by receptors of the immune system.
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38
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Piepenbrink KH, Gloor BE, Armstrong KM, Baker BM. Methods for quantifying T cell receptor binding affinities and thermodynamics. Methods Enzymol 2009; 466:359-81. [PMID: 21609868 DOI: 10.1016/s0076-6879(09)66015-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
αβ T cell receptors (TCRs) recognize peptide antigens bound and presented by class I or class II major histocompatibility complex (MHC) proteins. Recognition of a peptide/MHC complex is required for initiation and propagation of a cellular immune response, as well as the development and maintenance of the T cell repertoire. Here, we discuss methods to quantify the affinities and thermodynamics of interactions between soluble ectodomains of TCRs and their peptide/MHC ligands, focusing on titration calorimetry, surface plasmon resonance, and fluorescence anisotropy. As TCRs typically bind ligand with weak-to-moderate affinities, we focus the discussion on means to enhance the accuracy and precision of low-affinity measurements. In addition to further elucidating the biology of the T cell mediated immune response, more reliable low-affinity measurements will aid with more probing studies with mutants or altered peptides that can help illuminate the physical underpinnings of how TCRs achieve their remarkable recognition properties.
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Affiliation(s)
- Kurt H Piepenbrink
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
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39
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Horlock C, Stott B, Dyson J, Ogg G, McPherson T, Jones L, Sewell AK, Wooldridge L, Cole DK, Stebbing J, Savage P. ELISPOT and functional T cell analyses using HLA mono-specific target cells. J Immunol Methods 2009; 350:150-60. [DOI: 10.1016/j.jim.2009.08.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 08/14/2009] [Accepted: 08/18/2009] [Indexed: 10/20/2022]
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40
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Pien GC, Basner-Tschakarjan E, Hui DJ, Mentlik AN, Finn JD, Hasbrouck NC, Zhou S, Murphy SL, Maus MV, Mingozzi F, Orange JS, High KA. Capsid antigen presentation flags human hepatocytes for destruction after transduction by adeno-associated viral vectors. J Clin Invest 2009; 119:1688-95. [PMID: 19436115 PMCID: PMC2689109 DOI: 10.1172/jci36891] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 03/23/2009] [Indexed: 01/25/2023] Open
Abstract
Adeno-associated virus (AAV) vectors are effective gene delivery vehicles mediating long-lasting transgene expression. Data from a clinical trial of AAV2-mediated hepatic transfer of the Factor IX gene (F9) into hemophilia B subjects suggests that CTL responses against AAV capsid can eliminate transduced hepatocytes and prevent long-term F9 expression. However, the capacity of hepatocytes to present AAV capsid-derived antigens has not been formally demonstrated, nor whether transduction by AAV sensitizes hepatocytes for CTL-mediated destruction. To investigate the fate of capsids after transduction, we engineered a soluble TCR for the detection of capsid-derived peptide:MHC I (pMHC) complexes. TCR multimers exhibited antigen and HLA specificity and possessed high binding affinity for cognate pMHC complexes. With this reagent, capsid pMHC complexes were detectable by confocal microscopy following AAV-mediated transduction of human hepatocytes. Although antigen presentation was modest, it was sufficient to flag transduced cells for CTL-mediated lysis in an in vitro killing assay. Destruction of hepatocytes was inhibited by soluble TCR, demonstrating a possible application for this reagent in blocking undesirable CTL responses. Together, these studies provide a mechanism for the loss of transgene expression and transient elevations in aminotransferases following AAV-mediated hepatic gene transfer in humans and a potential therapeutic intervention to abrogate these limitations imposed by the host T cell response.
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Affiliation(s)
- Gary C. Pien
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Etiena Basner-Tschakarjan
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Daniel J. Hui
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ashley N. Mentlik
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jonathan D. Finn
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Nicole C. Hasbrouck
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Shangzhen Zhou
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Samuel L. Murphy
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Marcela V. Maus
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Federico Mingozzi
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jordan S. Orange
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Katherine A. High
- Division of Allergy and Immunology,
Division of Hematology, and
Howard Hughes Medical Institute, Children’s Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania, USA
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41
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Haidar JN, Pierce B, Yu Y, Tong W, Li M, Weng Z. Structure-based design of a T-cell receptor leads to nearly 100-fold improvement in binding affinity for pepMHC. Proteins 2009; 74:948-60. [PMID: 18767161 DOI: 10.1002/prot.22203] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
T-cell receptors (TCRs) are proteins that recognize peptides from foreign proteins bound to the major histocompatibility complex (MHC) on the surface of an antigen-presenting cell. This interaction enables the T cells to initiate a cell-mediated immune response to terminate cells displaying the foreign peptide on their MHC. Naturally occurring TCRs have high specificity but low affinity toward the peptide-MHC (pepMHC) complex. This prevents the usage of solubilized TCRs for diagnosis and treatment of viral infections or cancers. Efforts to enhance the binding affinity of several TCRs have been reported in recent years, through randomized libraries and in vitro selection. However, there have been no reported efforts to enhance the affinity via structure-based design, which allows more control and understanding of the mechanism of improvement. Here, we have applied structure-based design to a human TCR to improve its pepMHC binding. Our design method evolved based on iterative steps of prediction, testing, and generating more predictions based on the new data. The final design function, named ZAFFI, has a correlation of 0.77 and average error of 0.35 kcal/mol with the binding free energies of 26 point mutations for this system that we measured by surface plasmon resonance (SPR). Applying the filter that we developed to remove nonbinding predictions, this correlation increases to 0.85, and the average error decreases to 0.3 kcal/mol. Using this algorithm, we predicted and tested several point mutations that improved binding, with one giving over sixfold binding improvement. Four of the point mutations that improved binding were then combined to give a mutant TCR that binds the pepMHC 99 times more strongly than the wild-type TCR.
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Affiliation(s)
- Jaafar N Haidar
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02215, USA
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42
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Wooldridge L, Lissina A, Cole DK, van den Berg HA, Price DA, Sewell AK. Tricks with tetramers: how to get the most from multimeric peptide-MHC. Immunology 2009; 126:147-64. [PMID: 19125886 PMCID: PMC2632693 DOI: 10.1111/j.1365-2567.2008.02848.x] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Revised: 03/18/2008] [Accepted: 03/18/2008] [Indexed: 01/16/2023] Open
Abstract
The development of fluorochrome-conjugated peptide-major histocompatibility complex (pMHC) multimers in conjunction with continuing advances in flow cytometry has transformed the study of antigen-specific T cells by enabling their visualization, enumeration, phenotypic characterization and isolation from ex vivo samples. Here, we bring together and discuss some of the 'tricks' that can be used to get the most out of pMHC multimers. These include: (1) simple procedures that can substantially enhance the staining intensity of cognate T cells with pMHC multimers; (2) the use of pMHC multimers to stain T cells with very-low-affinity T-cell receptor (TCR)/pMHC interactions, such as those that typically predominate in tumour-specific responses; and (3) the physical grading and clonotypic dissection of antigen-specific T cells based on the affinity of their cognate TCR using mutant pMHC multimers in conjunction with new approaches to the molecular analysis of TCR gene expression. We also examine how soluble pMHC can be used to examine T-cell activation, manipulate T-cell responses and study allogeneic and superantigen interactions with TCRs. Finally, we discuss the problems that arise with pMHC class II (pMHCII) multimers because of the low affinity of TCR/pMHCII interactions and lack of 'coreceptor help'.
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Affiliation(s)
- Linda Wooldridge
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Henry Wellcome Building, Heath Park, Cardiff, UK
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43
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Chattopadhyay PK, Melenhorst JJ, Ladell K, Gostick E, Scheinberg P, Barrett AJ, Wooldridge L, Roederer M, Sewell AK, Price DA. Techniques to improve the direct ex vivo detection of low frequency antigen-specific CD8+ T cells with peptide-major histocompatibility complex class I tetramers. Cytometry A 2008; 73:1001-9. [PMID: 18836993 DOI: 10.1002/cyto.a.20642] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The ability to quantify and characterize antigen-specific CD8+ T cells irrespective of functional readouts using fluorochrome-conjugated peptide-major histocompatibility complex class I (pMHCI) tetramers in conjunction with flow cytometry has transformed our understanding of cellular immune responses over the past decade. In the case of prevalent CD8+ T cell populations that engage cognate pMHCI tetramers with high avidities, direct ex vivo identification and subsequent data interpretation is relatively straightforward. However, the accurate identification of low frequency antigen-specific CD8+ T cell populations can be complicated, especially in situations where T cell receptor-mediated tetramer binding occurs at low avidities. Here, we highlight a few simple techniques that can be employed to improve the visual resolution, and hence the accurate quantification, of tetramer binding CD8+ T cell populations by flow cytometry. These methodological modifications enhance signal intensity, especially in the case of specific CD8+ T cell populations that bind cognate antigen with low avidities, minimize background noise, and enable improved discrimination of true pMHCI tetramer binding events from nonspecific uptake.
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Affiliation(s)
- Pratip K Chattopadhyay
- Immunotechnology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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44
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Protein kinase inhibitors substantially improve the physical detection of T-cells with peptide-MHC tetramers. J Immunol Methods 2008; 340:11-24. [PMID: 18929568 PMCID: PMC3052435 DOI: 10.1016/j.jim.2008.09.014] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 09/09/2008] [Accepted: 09/11/2008] [Indexed: 11/21/2022]
Abstract
Flow cytometry with fluorochrome-conjugated peptide-major histocompatibility complex (pMHC) tetramers has transformed the study of antigen-specific T-cells by enabling their visualization, enumeration, phenotypic characterization and isolation from ex vivo samples. Here, we demonstrate that the reversible protein kinase inhibitor (PKI) dasatinib improves the staining intensity of human (CD8+ and CD4+) and murine T-cells without concomitant increases in background staining. Dasatinib enhances the capture of cognate pMHC tetramers from solution and produces higher intensity staining at lower pMHC concentrations. Furthermore, dasatinib reduces pMHC tetramer-induced cell death and substantially lowers the T-cell receptor (TCR)/pMHC interaction affinity threshold required for cell staining. Accordingly, dasatinib permits the identification of T-cells with very low affinity TCR/pMHC interactions, such as those that typically predominate in tumour-specific responses and autoimmune conditions that are not amenable to detection by current technology.
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45
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Anikeeva N, Mareeva T, Liu W, Sykulev Y. Can oligomeric T-cell receptor be used as a tool to detect viral peptide epitopes on infected cells? Clin Immunol 2008; 130:98-109. [PMID: 18845488 DOI: 10.1016/j.clim.2008.08.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 07/19/2008] [Indexed: 11/25/2022]
Abstract
We have utilized soluble HIV Gag-specific T-cell receptor (TCR) D3 with low affinity and TCR-like antibody 25-D1.16 recognizing its natural peptide-MHC (pMHC) ligand with high affinity to determine how affinity and off-rate of the receptor-pMHC interactions affect the sensitivity of pMHC detection on the cell surface. We found that with soluble TCR cognate pMHCs can be detected only at relatively high cell surface densities when the TCR was oligomerized using either Streptavidin or quantum dot (QD) scaffolds. While the higher affinity probe led to a greater sensitivity of pMHC detection, monomers and oligomers of the probe showed essentially the same detection limit, which is restricted by the sensitivity of standard flow cytometry technique. We have also shown that imaging of QD/TCR specifically bound to cognate pMHC on the cell surface yielded a very bright fluorescent signal that can enhance the sensitivity of viral peptide detection on infected cells.
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Affiliation(s)
- Nadia Anikeeva
- Department of Microbiology and Immunology and Kimmel Cancer Center, BLSB 650, Thomas Jefferson University, Philadelphia, PA 19107, USA
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46
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Melenhorst JJ, Scheinberg P, Chattopadhyay PK, Lissina A, Gostick E, Cole DK, Wooldridge L, van den Berg HA, Bornstein E, Hensel NF, Douek DC, Roederer M, Sewell AK, Barrett AJ, Price DA. Detection of low avidity CD8(+) T cell populations with coreceptor-enhanced peptide-major histocompatibility complex class I tetramers. J Immunol Methods 2008; 338:31-9. [PMID: 18675271 PMCID: PMC2714739 DOI: 10.1016/j.jim.2008.07.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2008] [Revised: 05/08/2008] [Accepted: 07/01/2008] [Indexed: 10/21/2022]
Abstract
The development of soluble recombinant peptide-major histocompatibility complex class I (pMHCI) molecules conjugated in multimeric form to fluorescent labels has enabled the physical quantification and characterization of antigen-specific CD8(+) T cell populations by flow cytometry. Several factors determine the binding threshold that enables visualization of cognate CD8(+) T cells with these reagents; these include the affinity of the T cell receptor (TCR) for pMHCI antigen. Here, we show that multimers constructed from peptide-human leukocyte antigen (pHLA) A0201 monomers engineered in the heavy chain alpha2 domain to enhance CD8 binding (K(D) approximately 85 microM) without impacting the TCR binding platform can detect cognate CD8(+) T cells bearing low affinity TCRs that are not visible with the corresponding wildtype pHLA A0201 multimeric complexes. Mechanistically, this effect is mediated by a disproportionate enhancement of the TCR/pMHCI association rate. In direct ex vivo applications, these coreceptor-enhanced multimers exhibit faithful cognate binding properties; concomitant increases in background staining within the non-cognate CD8(+) T cell population can be resolved phenotypically using polychromatic flow cytometry as a mixture of naïve and memory cells. These findings provide the first validation of a novel approach to the physical detection of low avidity antigen-specific CD8(+) T cell populations; such coreceptor-enhanced multimeric reagents are likely to be useful in a multitude of settings for the detection of auto-immune, tumor-specific and cross-reactive CD8(+) T cells.
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Affiliation(s)
- J. Joseph Melenhorst
- Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Phillip Scheinberg
- Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Pratip K. Chattopadhyay
- Immunotechnology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Anna Lissina
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Emma Gostick
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - David K. Cole
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Linda Wooldridge
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | | | - Ethan Bornstein
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nancy F. Hensel
- Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Daniel C. Douek
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mario Roederer
- Immunotechnology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Andrew K. Sewell
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - A. John Barrett
- Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - David A. Price
- Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
- Department of Medical Biochemistry and Immunology, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
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47
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Balagurunathan Y, Morse DL, Hostetter G, Shanmugam V, Stafford P, Shack S, Pearson J, Trissal M, Demeure MJ, Von Hoff DD, Hruby VJ, Gillies RJ, Han H. Gene expression profiling-based identification of cell-surface targets for developing multimeric ligands in pancreatic cancer. Mol Cancer Ther 2008; 7:3071-80. [PMID: 18765825 DOI: 10.1158/1535-7163.mct-08-0402] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Multimeric ligands are ligands that contain multiple binding domains that simultaneously target multiple cell-surface proteins. Due to cooperative binding, multimeric ligands can have high avidity for cells (tumor) expressing all targeting proteins and only show minimal binding to cells (normal tissues) expressing none or only some of the targets. Identifying combinations of targets that concurrently express in tumor cells but not in normal cells is a challenging task. Here, we describe a novel approach for identifying such combinations using genome-wide gene expression profiling followed by immunohistochemistry. We first generated a database of mRNA gene expression profiles for 28 pancreatic cancer specimens and 103 normal tissue samples representing 28 unique tissue/cell types using DNA microarrays. The expression data for genes that encode proteins with cell-surface epitopes were then extracted from the database and analyzed using a novel multivariate rule-based computational approach to identify gene combinations that are expressed at an efficient binding level in tumors but not in normal tissues. These combinations were further ranked according to the proportion of tumor samples that expressed the sets at efficient levels. Protein expression of the genes contained in the top ranked combinations was confirmed using immunohistochemistry on a pancreatic tumor tissue and normal tissue microarrays. Coexpression of targets was further validated by their combined expression in pancreatic cancer cell lines using immunocytochemistry. These validated gene combinations thus encompass a list of cell-surface targets that can be used to develop multimeric ligands for the imaging and treatment of pancreatic cancer.
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48
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A T-cell receptor associated with naturally occurring human tumor immunity. Proc Natl Acad Sci U S A 2008; 104:19073-8. [PMID: 18045792 DOI: 10.1073/pnas.0704336104] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The onconeural antigens appear to serve as tumor rejection antigens in the paraneoplastic neurologic disorders. Here, we used an unbiased peptide binding screen, followed by studies in HLA-A2.1 transgenic mice to identify naturally processed HLA-A2.1 restricted epitopes of the paraneoplastic cerebellar degeneration breast/ovarian cancer antigen cdr2. These mice were used to clone high-avidity cdr2-specific CD8(+) T cells that recognize human tumor cells presenting endogenously loaded MHC class I-cdr2 peptide. T cells with this specificity were detected in the peripheral blood of two HLA-A2.1(+) paraneoplastic cerebellar degeneration patients. We cloned T cell receptor (TCR) alpha and beta genes from cdr2-specific T cells; electroporation of RNA encoding this TCR turned nonreactive donor T cells into efficient killers of human cdr2-expressing tumor cells. Cloned cdr2-specific TCR genes provide a clinically relevant means for immunologic targeting of human gynecologic cancers.
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49
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Løset GÅ, Lunde E, Bogen B, Brekke OH, Sandlie I. Functional phage display of two murine alpha/beta T-cell receptors is strongly dependent on fusion format, mode and periplasmic folding assistance. Protein Eng Des Sel 2007; 20:461-72. [PMID: 17925331 DOI: 10.1093/protein/gzm044] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Phage display has been instrumental for the success of antibody (Ab) technology. The aim of the present study was to explore phage display of soluble T-cell receptors (TCRs). A library platform that supports engineering and selection of improved TCRs to be used as detection reagents for specific antigen presentation will be very useful. In such applications, high, equal and clone independent display levels are a prerequisite for 'fair' selection. Therefore, we explored how different pIII fusion formats and modes affected the display levels of two murine alpha/beta TCRs. Both are derived from T-cell clones associated with the MOPC315 myeloma model. The results show that the design of the pIII fusion particle significantly affects the subsequent display levels. Furthermore, successful display may be obtained both in phagemid and phage versions. Importantly, improvement of poor display can be achieved by over-expressing the periplasmic chaperone FkpA.
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Affiliation(s)
- G Å Løset
- Department of Molecular Biosciences, University of Oslo, N-0316 Oslo, Norway.
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50
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Purbhoo MA, Li Y, Sutton DH, Brewer JE, Gostick E, Bossi G, Laugel B, Moysey R, Baston E, Liddy N, Cameron B, Bennett AD, Ashfield R, Milicic A, Price DA, Classon BJ, Sewell AK, Jakobsen BK. The HLA A*0201-restricted hTERT(540-548) peptide is not detected on tumor cells by a CTL clone or a high-affinity T-cell receptor. Mol Cancer Ther 2007; 6:2081-91. [PMID: 17620437 DOI: 10.1158/1535-7163.mct-07-0092] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Tumor-associated human telomerase reverse transcriptase (hTERT) is expressed in >85% of human tumors but not in most normal cells. As a result, this antigen has received considerable attention from those interested in cancer immunotherapy. Specifically, there has been strong interest in MHC class I-associated peptides derived from hTERT because these are expressed on the cell surface and thus may enable the targeting of tumor cells. Much of this interest has focused on peptide 540-548, ILAKFLHWL, which was predicted to exhibit the strongest binding to the common HLA A*0201 presenting molecule. The hTERT(540-548) peptide is currently being assessed in therapeutic vaccination trials; however, there is controversy surrounding whether it is naturally processed and presented on the surface of neoplastic cells. Here, we generate two highly sensitive reagents to assess the presentation of hTERT(540-548) on tumor cells: (a) a CD8(+) CTL clone, and (b) a recombinant T-cell receptor (TCR) that binds with picomolar affinity and a half-life exceeding 14 h. This TCR enables the identification of individual HLA A2-hTERT(540-548) complexes on the cell surface. The use of both this TCR and the highly antigen-sensitive CTL clone shows that the hTERT(540-548) peptide cannot be detected on the surface of tumor cells, indicating that this peptide is not a naturally presented epitope. We propose that, in future, rigorous methods must be applied for the validation of peptide epitopes used for clinical applications.
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Affiliation(s)
- Marco A Purbhoo
- Avidex Ltd., 57-59 Milton Park, Abingdon, OX14 4RX, United Kingdom
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