1
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Paterson RL, La Manna MP, Arena De Souza V, Walker A, Gibbs-Howe D, Kulkarni R, Fergusson JR, Mulakkal NC, Monteiro M, Bunjobpol W, Dembek M, Martin-Urdiroz M, Grant T, Barber C, Garay-Baquero DJ, Tezera LB, Lowne D, Britton-Rivet C, Pengelly R, Chepisiuk N, Singh PK, Woon AP, Powlesland AS, McCully ML, Caccamo N, Salio M, Badami GD, Dorrell L, Knox A, Robinson R, Elkington P, Dieli F, Lepore M, Leonard S, Godinho LF. An HLA-E-targeted TCR bispecific molecule redirects T cell immunity against Mycobacterium tuberculosis. Proc Natl Acad Sci U S A 2024; 121:e2318003121. [PMID: 38691588 PMCID: PMC11087797 DOI: 10.1073/pnas.2318003121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 03/08/2024] [Indexed: 05/03/2024] Open
Abstract
Peptides presented by HLA-E, a molecule with very limited polymorphism, represent attractive targets for T cell receptor (TCR)-based immunotherapies to circumvent the limitations imposed by the high polymorphism of classical HLA genes in the human population. Here, we describe a TCR-based bispecific molecule that potently and selectively binds HLA-E in complex with a peptide encoded by the inhA gene of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis in humans. We reveal the biophysical and structural bases underpinning the potency and specificity of this molecule and demonstrate its ability to redirect polyclonal T cells to target HLA-E-expressing cells transduced with mycobacterial inhA as well as primary cells infected with virulent Mtb. Additionally, we demonstrate elimination of Mtb-infected cells and reduction of intracellular Mtb growth. Our study suggests an approach to enhance host T cell immunity against Mtb and provides proof of principle for an innovative TCR-based therapeutic strategy overcoming HLA polymorphism and therefore applicable to a broader patient population.
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Affiliation(s)
| | - Marco P. La Manna
- Department of Biomedicine, Neurosciences and Advanced Diagnostic, University of Palermo, Palermo90127, Italy
- Central Laboratory of Advanced Diagnosis and Biomedical Research, Azienda Ospedaliera Universitaria Policlinico Paolo Giaccone, University of Palermo, Palermo90127, Italy
| | | | - Andrew Walker
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Dawn Gibbs-Howe
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Rakesh Kulkarni
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | | | | | - Mauro Monteiro
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | | | - Marcin Dembek
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | | | - Tressan Grant
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Claire Barber
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Diana J. Garay-Baquero
- National Institute for Health and Care Research, Biomedical Research Centre and Institute for Life Sciences, Faculty of Medicine, University of Southampton, SouthamptonSO16 6YD, United Kingdom
| | - Liku Bekele Tezera
- Department of Biomedicine, Neurosciences and Advanced Diagnostic, University of Palermo, Palermo90127, Italy
| | - David Lowne
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | | | - Robert Pengelly
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | | | | | - Amanda P. Woon
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | | | | | - Nadia Caccamo
- Department of Biomedicine, Neurosciences and Advanced Diagnostic, University of Palermo, Palermo90127, Italy
- Central Laboratory of Advanced Diagnosis and Biomedical Research, Azienda Ospedaliera Universitaria Policlinico Paolo Giaccone, University of Palermo, Palermo90127, Italy
| | - Mariolina Salio
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Giusto Davide Badami
- Department of Biomedicine, Neurosciences and Advanced Diagnostic, University of Palermo, Palermo90127, Italy
- Central Laboratory of Advanced Diagnosis and Biomedical Research, Azienda Ospedaliera Universitaria Policlinico Paolo Giaccone, University of Palermo, Palermo90127, Italy
| | - Lucy Dorrell
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Andrew Knox
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Ross Robinson
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Paul Elkington
- National Institute for Health and Care Research, Biomedical Research Centre and Institute for Life Sciences, Faculty of Medicine, University of Southampton, SouthamptonSO16 6YD, United Kingdom
| | - Francesco Dieli
- Department of Biomedicine, Neurosciences and Advanced Diagnostic, University of Palermo, Palermo90127, Italy
- Central Laboratory of Advanced Diagnosis and Biomedical Research, Azienda Ospedaliera Universitaria Policlinico Paolo Giaccone, University of Palermo, Palermo90127, Italy
| | - Marco Lepore
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Sarah Leonard
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
| | - Luis F. Godinho
- Immunocore Ltd., Abingdon, OxfordshireOX14 4RY, United Kingdom
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2
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Wallace Z, Heunis T, Paterson RL, Suckling RJ, Grant T, Dembek M, Donoso J, Brener J, Long J, Bunjobpol W, Gibbs-Howe D, Kay DP, Leneghan DB, Godinho LF, Walker A, Singh PK, Knox A, Leonard S, Dorrell L. Instability of the HLA-E peptidome of HIV presents a major barrier to therapeutic targeting. Mol Ther 2024; 32:678-688. [PMID: 38219014 PMCID: PMC10928138 DOI: 10.1016/j.ymthe.2024.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 11/14/2023] [Accepted: 01/08/2024] [Indexed: 01/15/2024] Open
Abstract
Naturally occurring T cells that recognize microbial peptides via HLA-E, a nonpolymorphic HLA class Ib molecule, could provide the foundation for new universal immunotherapeutics. However, confidence in the biological relevance of putative ligands is crucial, given that the mechanisms by which pathogen-derived peptides can access the HLA-E presentation pathway are poorly understood. We systematically interrogated the HIV proteome using immunopeptidomic and bioinformatic approaches, coupled with biochemical and cellular assays. No HIV HLA-E peptides were identified by tandem mass spectrometry analysis of HIV-infected cells. In addition, all bioinformatically predicted HIV peptide ligands (>80) were characterized by poor complex stability. Furthermore, infected cell elimination assays using an affinity-enhanced T cell receptor bispecific targeted to a previously reported HIV Gag HLA-E epitope demonstrated inconsistent presentation of the peptide, despite normal HLA-E expression on HIV-infected cells. This work highlights the instability of the HIV HLA-E peptidome as a major challenge for drug development.
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Affiliation(s)
- Zoë Wallace
- Immunocore Ltd., Abingdon, Oxfordshire OX14 4RY, UK.
| | - Tiaan Heunis
- Immunocore Ltd., Abingdon, Oxfordshire OX14 4RY, UK
| | | | | | | | | | - Jose Donoso
- Immunocore Ltd., Abingdon, Oxfordshire OX14 4RY, UK
| | | | - Joshua Long
- Immunocore Ltd., Abingdon, Oxfordshire OX14 4RY, UK
| | | | | | - Daniel P Kay
- Immunocore Ltd., Abingdon, Oxfordshire OX14 4RY, UK
| | | | | | | | | | - Andrew Knox
- Immunocore Ltd., Abingdon, Oxfordshire OX14 4RY, UK
| | | | - Lucy Dorrell
- Immunocore Ltd., Abingdon, Oxfordshire OX14 4RY, UK
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3
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Yin V, Devine PWA, Saunders JC, Barendregt A, Cusdin F, Ristani A, Hines A, Shepherd S, Dembek M, Dobson CL, Snijder J, Bond NJ, Heck AJR. Stochastic assembly of biomacromolecular complexes: impact and implications on charge interpretation in native mass spectrometry. Chem Sci 2023; 14:9316-9327. [PMID: 37712025 PMCID: PMC10498669 DOI: 10.1039/d3sc03228k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 08/16/2023] [Indexed: 09/16/2023] Open
Abstract
Native mass spectrometry is a potent method for characterizing biomacromolecular assemblies. A critical aspect to extracting accurate mass information is the correct inference of the ion ensemble charge states. While a variety of experimental strategies and algorithms have been developed to facilitate this, virtually all approaches rely on the implicit assumption that any peaks in a native mass spectrum can be directly attributed to an underlying charge state distribution. Here, we demonstrate that this paradigm breaks down for several types of macromolecular protein complexes due to the intrinsic heterogeneity induced by the stochastic nature of their assembly. Utilizing several protein assemblies of adeno-associated virus capsids and ferritin, we demonstrate that these particles can produce a variety of unexpected spectral appearances, some of which appear superficially similar to a resolved charge state distribution. When interpreted using conventional charge inference strategies, these distorted spectra can lead to substantial errors in the calculated mass (up to ∼5%). We provide a novel analytical framework to interpret and extract mass information from these spectra by combining high-resolution native mass spectrometry, single particle Orbitrap-based charge detection mass spectrometry, and sophisticated spectral simulations based on a stochastic assembly model. We uncover that these mass spectra are extremely sensitive to not only mass heterogeneity within the subunits, but also to the magnitude and width of their charge state distributions. As we postulate that many protein complexes assemble stochastically, this framework provides a generalizable solution, further extending the usability of native mass spectrometry in the characterization of biomacromolecular assemblies.
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Affiliation(s)
- Victor Yin
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University Padualaan 8, 3584 CH Utrecht The Netherlands
- Netherlands Proteomics Center Padualaan 8, 3584 CH Utrecht The Netherlands
| | - Paul W A Devine
- Analytical Sciences, Biopharmaceutical Development, R & D, AstraZeneca Granta Park Cambridge UK
| | - Janet C Saunders
- In Vivo Expressed Biologics, Discovery Sciences, R & D, AstraZeneca Granta Park Cambridge UK
| | - Arjan Barendregt
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University Padualaan 8, 3584 CH Utrecht The Netherlands
- Netherlands Proteomics Center Padualaan 8, 3584 CH Utrecht The Netherlands
| | - Fiona Cusdin
- In Vivo Expressed Biologics, Discovery Sciences, R & D, AstraZeneca Granta Park Cambridge UK
| | - Alexandra Ristani
- In Vivo Expressed Biologics, Discovery Sciences, R & D, AstraZeneca Granta Park Cambridge UK
| | - Alistair Hines
- Analytical Sciences, Biopharmaceutical Development, R & D, AstraZeneca Granta Park Cambridge UK
| | - Sam Shepherd
- Analytical Sciences, Biopharmaceutical Development, R & D, AstraZeneca Granta Park Cambridge UK
| | - Marcin Dembek
- Purification Process Sciences, Biopharmaceutical Development, R & D, AstraZeneca Granta Park Cambridge UK
| | - Claire L Dobson
- In Vivo Expressed Biologics, Discovery Sciences, R & D, AstraZeneca Granta Park Cambridge UK
| | - Joost Snijder
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University Padualaan 8, 3584 CH Utrecht The Netherlands
- Netherlands Proteomics Center Padualaan 8, 3584 CH Utrecht The Netherlands
| | - Nicholas J Bond
- Analytical Sciences, Biopharmaceutical Development, R & D, AstraZeneca Granta Park Cambridge UK
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University Padualaan 8, 3584 CH Utrecht The Netherlands
- Netherlands Proteomics Center Padualaan 8, 3584 CH Utrecht The Netherlands
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4
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Barber C, De Souza VA, Paterson RL, Martin‐Urdiroz M, Mulakkal NC, Srikannathasan V, Connolly M, Phillips G, Foong‐Leong T, Pengelly R, Karuppiah V, Grant T, Dembek M, Verma A, Gibbs‐Howe D, Blicher TH, Knox A, Robinson RA, Cole DK, Leonard S. Structure-guided stabilization of pathogen-derived peptide-HLA-E complexes using non-natural amino acids conserves native TCR recognition. Eur J Immunol 2022; 52:618-632. [PMID: 35108401 PMCID: PMC9306587 DOI: 10.1002/eji.202149745] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 11/26/2021] [Accepted: 01/12/2022] [Indexed: 12/02/2022]
Abstract
The nonpolymorphic class Ib molecule, HLA-E, primarily presents peptides from HLA class Ia leader peptides, providing an inhibitory signal to NK cells via CD94/NKG2 interactions. Although peptides of pathogenic origin can also be presented by HLA-E to T cells, the molecular basis underpinning their role in antigen surveillance is largely unknown. Here, we solved a co-complex crystal structure of a TCR with an HLA-E presented peptide (pHLA-E) from bacterial (Mycobacterium tuberculosis) origin, and the first TCR-pHLA-E complex with a noncanonically presented peptide from viral (HIV) origin. The structures provided a molecular foundation to develop a novel method to introduce cysteine traps using non-natural amino acid chemistry that stabilized pHLA-E complexes while maintaining native interface contacts between the TCRs and different pHLA-E complexes. These pHLA-E monomers could be used to isolate pHLA-E-specific T cells, with obvious utility for studying pHLA-E restricted T cells, and for the identification of putative therapeutic TCRs.
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5
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Wilgus ML, Abtin F, Markovic D, Tashkin DP, Phillips JE, Buhr RG, Flynn MJ, Dembek M, Cooper CB, Barjaktarevic I. Panlobular emphysema is associated with COPD disease severity: A study of emphysema subtype by computed tomography. Respir Med 2021; 192:106717. [PMID: 35026616 DOI: 10.1016/j.rmed.2021.106717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 11/30/2021] [Accepted: 12/12/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND Computed tomography has the potential to inform COPD prognosis. We sought to determine associations of emphysema phenotype with clinical parameters including lung function, inflammatory markers, and quality of life. METHODS Participants of this single-center observational cohort (n = 83) were 40-80 years old, had ≥10 pack-year smoking, and a diagnosis of COPD confirmed by spirometry. All participants had available historic chest CT scans which were systematically reviewed by a single expert radiologist and scored for emphysema subtype, extent, and distribution. Associations between radiographic findings and clinical parameters were determined. RESULTS Median age of participants was 72 years, median smoking 40 pack-years, and median FEV1 59% predicted. 84% of the participants had radiographic emphysema. Of those, 26% had panlobular emphysema (PLE), 68% centrilobular emphysema (CLE), and 6% paraseptal emphysema (PSE). As compared to the participants with no radiographic emphysema, the presence of PLE-dominant emphysema was associated with a lower BMI (P = 0.012) and greater extent of emphysema (P = 0.014). After adjusting for age, sex, and pack-years smoking history, PLE was associated with greater airflow obstruction by FEV1% (48% vs 71%, P = 0.005), greater symptom burden by CAT score (18 vs 9, P = 0.015), worse quality of life by SGRQ score (43 vs 22, P = 0.025), and more systemic inflammation by erythrocyte sedimentation rate (P = 0.001). CLE- or PSE-dominant emphysema were not similarly associated with clinical features or symptom burden. CONCLUSIONS The presence of PLE-dominant emphysema was associated with greater extent of emphysema, greater airflow obstruction, increased respiratory symptoms, worse quality of life, and systemic inflammation. Further investigation is indicated to explore the pathogenesis of the PLE phenotype and the prognostic and treatment implications of PLE.
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Affiliation(s)
- M L Wilgus
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
| | - F Abtin
- Division of Thoracic Radiology, Department of Radiology, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
| | - D Markovic
- Department of Medicine Statistics Core, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
| | - D P Tashkin
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
| | - J E Phillips
- Inflammation Discovery Research, Amgen, Thousand Oaks, CA, USA
| | - R G Buhr
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA; Department of Medicine, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, USA
| | - M J Flynn
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA; Division of Pulmonology, Kaiser Permanente Sunnyside Medical Center, Clackamas, OR, USA
| | - M Dembek
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA; Department of Physician Assistant Studies, Bay Path University, Longmeadow, MA, USA
| | - C B Cooper
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA; Department of Physiology, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA
| | - I Barjaktarevic
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA.
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6
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Fergusson JR, Wallace Z, Connolly MM, Woon AP, Suckling RJ, Hine DW, Barber C, Bunjobpol W, Choi B, Crespillo S, Dembek M, Dieckmann N, Donoso J, Godinho LF, Grant T, Howe D, McCully ML, Perot C, Sarkar A, Seifert FU, Singh PK, Stegmann KA, Turner B, Verma A, Walker A, Leonard S, Maini MK, Wiederhold K, Dorrell L, Simmons R, Knox A. Immune-Mobilizing Monoclonal T Cell Receptors Mediate Specific and Rapid Elimination of Hepatitis B-Infected Cells. Hepatology 2020; 72:1528-1540. [PMID: 32770836 PMCID: PMC7702151 DOI: 10.1002/hep.31503] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/17/2020] [Accepted: 07/01/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND AIMS Therapies for chronic hepatitis B virus (HBV) infection are urgently needed because of viral integration, persistence of viral antigen expression, inadequate HBV-specific immune responses, and treatment regimens that require lifelong adherence to suppress the virus. Immune mobilizing monoclonal T Cell receptors against virus (ImmTAV) molecules represent a therapeutic strategy combining an affinity-enhanced T Cell receptor with an anti-CD3 T Cell-activating moiety. This bispecific fusion protein redirects T cells to specifically lyse infected cells expressing the target virus-derived peptides presented by human leukocyte antigen (HLA). APPROACH AND RESULTS ImmTAV molecules specific for HLA-A*02:01-restricted epitopes from HBV envelope, polymerase, and core antigens were engineered. The ability of ImmTAV-Env to activate and redirect polyclonal T cells toward cells containing integrated HBV and cells infected with HBV was assessed using cytokine secretion assays and imaging-based killing assays. Elimination of infected cells was further quantified using a modified fluorescent hybridization of viral RNA assay. Here, we demonstrate that picomolar concentrations of ImmTAV-Env can redirect T cells from healthy and HBV-infected donors toward hepatocellular carcinoma (HCC) cells containing integrated HBV DNA resulting in cytokine release, which could be suppressed by the addition of a corticosteroid in vitro. Importantly, ImmTAV-Env redirection of T cells induced cytolysis of antigen-positive HCC cells and cells infected with HBV in vitro, causing a reduction of hepatitis B e antigen and specific loss of cells expressing viral RNA. CONCLUSIONS The ImmTAV platform has the potential to enable the elimination of infected cells by redirecting endogenous non-HBV-specific T cells, bypassing exhausted HBV-specific T cells. This represents a promising therapeutic option in the treatment of chronic hepatitis B, with our lead candidate now entering trials.
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MESH Headings
- Antibodies, Monoclonal/genetics
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal/therapeutic use
- CD3 Complex/antagonists & inhibitors
- Cell Line, Tumor
- Epitopes/immunology
- HLA-A2 Antigen/immunology
- Hepatitis B Surface Antigens/immunology
- Hepatitis B virus/immunology
- Hepatitis B virus/isolation & purification
- Hepatitis B, Chronic/drug therapy
- Hepatitis B, Chronic/immunology
- Hepatitis B, Chronic/virology
- Hepatocytes
- Humans
- Immunoconjugates/genetics
- Immunoconjugates/immunology
- Immunoconjugates/pharmacology
- Immunoconjugates/therapeutic use
- Lymphocyte Activation/drug effects
- Primary Cell Culture
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/therapeutic use
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/immunology
- Recombinant Fusion Proteins/pharmacology
- Recombinant Fusion Proteins/therapeutic use
- T-Lymphocytes/drug effects
- T-Lymphocytes/immunology
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Dawn Howe
- Immunocore LtdAbingdonUnited Kingdom
| | | | | | | | | | | | - Kerstin A. Stegmann
- Division of Infection and ImmunityInstitute of Immunity and TransplantationUniversity College LondonLondonUnited Kingdom
| | | | | | | | | | - Mala K. Maini
- Division of Infection and ImmunityInstitute of Immunity and TransplantationUniversity College LondonLondonUnited Kingdom
| | | | - Lucy Dorrell
- Immunocore LtdAbingdonUnited Kingdom
- Nuffield Department of MedicineUniversity of OxfordOxfordUnited Kingdom
- Oxford NIHR Biomedical Research CentreUniversity of OxfordOxfordUnited Kingdom
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7
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Dembek M, Kelly A, Barwinska-Sendra A, Tarrant E, Stanley WA, Vollmer D, Biboy J, Gray J, Vollmer W, Salgado PS. Peptidoglycan degradation machinery in Clostridium difficile forespore engulfment. Mol Microbiol 2019; 110:390-410. [PMID: 30066424 PMCID: PMC6221140 DOI: 10.1111/mmi.14091] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2018] [Indexed: 12/31/2022]
Abstract
Clostridium difficile remains the leading cause of antibiotic‐associated diarrhoea in hospitals worldwide, linked to significant morbidity and mortality. As a strict anaerobe, it produces dormant cell forms – spores – which allow it to survive in the aerobic environment. Importantly, spores are the transmission agent of C. difficile infections. A key aspect of sporulation is the engulfment of the future spore by the mother cell and several proteins have been proposed to be involved. Here, we investigated the role of the SpoIID, SpoIIM and SpoIIP (DMP) machinery and its interplay with the SpoIIQ:SpoIIIAH (Q:AH) complex in C. difficile. We show that, surprisingly, SpoIIM, the proposed machinery anchor, is not required for efficient engulfment and sporulation. We demonstrate the requirement of DP for engulfment due to their sequential peptidoglycan degradation activity, both in vitro and in vivo. Finally, new interactions within DMP and between DMP and Q:AH suggest that both systems form a single engulfment machinery to keep the mother cell and forespore membranes together throughout engulfment. This work sheds new light upon the engulfment process and on how different sporeformers might use the same components in different ways to drive spore formation.
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Affiliation(s)
- Marcin Dembek
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Abigail Kelly
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Anna Barwinska-Sendra
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Emma Tarrant
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Will A Stanley
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Daniela Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Jacob Biboy
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Joe Gray
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Waldemar Vollmer
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.,Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Paula S Salgado
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.,Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
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8
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Dembek M, Willing SE, Hong HA, Hosseini S, Salgado PS, Cutting SM. Inducible Expression of spo0A as a Universal Tool for Studying Sporulation in Clostridium difficile. Front Microbiol 2017; 8:1793. [PMID: 28983286 PMCID: PMC5613124 DOI: 10.3389/fmicb.2017.01793] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 09/05/2017] [Indexed: 01/01/2023] Open
Abstract
Clostridium difficile remains a leading nosocomial pathogen, putting considerable strain on the healthcare system. The ability to form endospores, highly resistant to environmental insults, is key to its persistence and transmission. However, important differences exist between the sporulation pathways of C. difficile and the model Gram-positive organism Bacillus subtilis. Amongst the challenges in studying sporulation in C. difficile is the relatively poor levels of sporulation and high heterogeneity in the sporulation process. To overcome these limitations we placed Ptet regulatory elements upstream of the master regulator of sporulation, spo0A, generating a new strain that can be artificially induced to sporulate by addition of anhydrotetracycline (ATc). We demonstrate that this strain is asporogenous in the absence of ATc, and that ATc can be used to drive faster and more efficient sporulation. Induction of Spo0A is titratable and this can be used in the study of the spo0A regulon both in vitro and in vivo, as demonstrated using a mouse model of C. difficile infection (CDI). Insights into differences between the sporulation pathways in B. subtilis and C. difficile gained by study of the inducible strain are discussed, further highlighting the universal interest of this tool. The Ptet-spo0A strain provides a useful background in which to generate mutations in genes involved in sporulation, therefore providing an exciting new tool to unravel key aspects of sporulation in C. difficile.
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Affiliation(s)
- Marcin Dembek
- Institute for Cell and Molecular Biosciences, Newcastle UniversityNewcastle upon Tyne, United Kingdom
| | - Stephanie E Willing
- School of Biological Sciences, Royal Holloway, University of LondonLondon, United Kingdom
| | - Huynh A Hong
- School of Biological Sciences, Royal Holloway, University of LondonLondon, United Kingdom
| | - Siamand Hosseini
- School of Biological Sciences, Royal Holloway, University of LondonLondon, United Kingdom
| | - Paula S Salgado
- Institute for Cell and Molecular Biosciences, Newcastle UniversityNewcastle upon Tyne, United Kingdom
| | - Simon M Cutting
- School of Biological Sciences, Royal Holloway, University of LondonLondon, United Kingdom
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Belton M, Brilha S, Manavaki R, Mauri F, Nijran K, Hong YT, Patel NH, Dembek M, Tezera L, Green J, Moores R, Aigbirhio F, Al-Nahhas A, Fryer TD, Elkington PT, Friedland JS. Hypoxia and tissue destruction in pulmonary TB. Thorax 2016; 71:1145-1153. [PMID: 27245780 PMCID: PMC5136721 DOI: 10.1136/thoraxjnl-2015-207402] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 02/27/2016] [Accepted: 03/24/2016] [Indexed: 02/04/2023]
Abstract
Background It is unknown whether lesions in human TB are hypoxic or whether this influences disease pathology. Human TB is characterised by extensive lung destruction driven by host matrix metalloproteinases (MMPs), particularly collagenases such as matrix metalloproteinase-1 (MMP-1). Methods We investigated tissue hypoxia in five patients with PET imaging using the tracer [18F]-fluoromisonidazole ([18F]FMISO) and by immunohistochemistry. We studied the regulation of MMP secretion in primary human cell culture model systems in normoxia, hypoxia, chemical hypoxia and by small interfering RNA (siRNA) inhibition. Results [18F]FMISO accumulated in regions of TB consolidation and around pulmonary cavities, demonstrating for the first time severe tissue hypoxia in man. Patlak analysis of dynamic PET data showed heterogeneous levels of hypoxia within and between patients. In Mycobacterium tuberculosis (M.tb)-infected human macrophages, hypoxia (1% pO2) upregulated MMP-1 gene expression 170-fold, driving secretion and caseinolytic activity. Dimethyloxalyl glycine (DMOG), a small molecule inhibitor which stabilises the transcription factor hypoxia-inducible factor (HIF)-1α, similarly upregulated MMP-1. Hypoxia did not affect mycobacterial replication. Hypoxia increased MMP-1 expression in primary respiratory epithelial cells via intercellular networks regulated by TB. HIF-1α and NF-κB regulated increased MMP-1 activity in hypoxia. Furthermore, M.tb infection drove HIF-1α accumulation even in normoxia. In human TB lung biopsies, epithelioid macrophages and multinucleate giant cells express HIF-1α. HIF-1α blockade, including by targeted siRNA, inhibited TB-driven MMP-1 gene expression and secretion. Conclusions Human TB lesions are severely hypoxic and M.tb drives HIF-1α accumulation, synergistically increasing collagenase activity which will lead to lung destruction and cavitation.
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Affiliation(s)
- Moerida Belton
- Section of Infectious Diseases and Immunity, Imperial College London, London, UK
| | - Sara Brilha
- Section of Infectious Diseases and Immunity, Imperial College London, London, UK
| | - Roido Manavaki
- Department of Radiology, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Francesco Mauri
- Department of Histopathology, Hammersmith Campus, Imperial College London, London, UK
| | - Kuldip Nijran
- Radiological Science Unit Charing Cross Campus, Department of Nuclear Medicine, Charing Cross Campus, Imperial College NHS Trust, London, UK
| | - Young T Hong
- Wolfson Brain Imaging Centre, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Neva H Patel
- Radiological Science Unit Charing Cross Campus, Department of Nuclear Medicine, Charing Cross Campus, Imperial College NHS Trust, London, UK
| | - Marcin Dembek
- Section of Infectious Diseases and Immunity, Imperial College London, London, UK
| | - Liku Tezera
- NIHR Respiratory Biomedical Research Unit, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Justin Green
- Section of Infectious Diseases and Immunity, Imperial College London, London, UK
| | - Rachel Moores
- Section of Infectious Diseases and Immunity, Imperial College London, London, UK
| | - Franklin Aigbirhio
- Wolfson Brain Imaging Centre, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Adil Al-Nahhas
- Radiological Science Unit Charing Cross Campus, Department of Nuclear Medicine, Charing Cross Campus, Imperial College NHS Trust, London, UK
| | - Tim D Fryer
- Wolfson Brain Imaging Centre, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Paul T Elkington
- Section of Infectious Diseases and Immunity, Imperial College London, London, UK.,NIHR Respiratory Biomedical Research Unit, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Jon S Friedland
- Section of Infectious Diseases and Immunity, Imperial College London, London, UK
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10
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Serrano M, Crawshaw AD, Dembek M, Monteiro JM, Pereira FC, Pinho MG, Fairweather NF, Salgado PS, Henriques AO. The SpoIIQ-SpoIIIAH complex of Clostridium difficile controls forespore engulfment and late stages of gene expression and spore morphogenesis. Mol Microbiol 2016; 100:204-28. [PMID: 26690930 PMCID: PMC4982068 DOI: 10.1111/mmi.13311] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2015] [Indexed: 11/29/2022]
Abstract
Engulfment of the forespore by the mother cell is a universal feature of endosporulation. In Bacillus subtilis, the forespore protein SpoIIQ and the mother cell protein SpoIIIAH form a channel, essential for endosporulation, through which the developing spore is nurtured. The two proteins also form a backup system for engulfment. Unlike in B. subtilis, SpoIIQ of Clostridium difficile has intact LytM zinc‐binding motifs. We show that spoIIQ or spoIIIAH deletion mutants of C. difficile result in anomalous engulfment, and that disruption of the SpoIIQ LytM domain via a single amino acid substitution (H120S) impairs engulfment differently. SpoIIQ and SpoIIQH120S interact with SpoIIIAH throughout engulfment. SpoIIQ, but not SpoIIQH120S, binds Zn2+, and metal absence alters the SpoIIQ‐SpoIIIAH complex in vitro. Possibly, SpoIIQH120S supports normal engulfment in some cells but not a second function of the complex, required following engulfment completion. We show that cells of the spoIIQ or spoIIIAH mutants that complete engulfment are impaired in post‐engulfment, forespore and mother cell‐specific gene expression, suggesting a channel‐like function. Both engulfment and a channel‐like function may be ancestral functions of SpoIIQ‐SpoIIIAH while the requirement for engulfment was alleviated through the emergence of redundant mechanisms in B. subtilis and related organisms.
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Affiliation(s)
- Mónica Serrano
- Microbial Development, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, Avenida da República, 2780-157, Oeiras, Portugal
| | - Adam D Crawshaw
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Marcin Dembek
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.,MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, UK
| | - João M Monteiro
- Bacterial Cell Biology Laboratory, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, Avenida da República, 2780-157, Oeiras, Portugal
| | - Fátima C Pereira
- Microbial Development, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, Avenida da República, 2780-157, Oeiras, Portugal
| | - Mariana Gomes Pinho
- Bacterial Cell Biology Laboratory, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, Avenida da República, 2780-157, Oeiras, Portugal
| | - Neil F Fairweather
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, UK
| | - Paula S Salgado
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Adriano O Henriques
- Microbial Development, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, Avenida da República, 2780-157, Oeiras, Portugal
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11
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Phetcharaburanin J, Hong HA, Colenutt C, Bianconi I, Sempere L, Permpoonpattana P, Smith K, Dembek M, Tan S, Brisson MC, Brisson AR, Fairweather NF, Cutting SM. The spore-associated protein BclA1 affects the susceptibility of animals to colonization and infection by Clostridium difficile. Mol Microbiol 2014; 92:1025-38. [PMID: 24720767 DOI: 10.1111/mmi.12611] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2014] [Indexed: 01/05/2023]
Abstract
The BclA protein is a major component of the outermost layer of spores of a number of bacterial species and Clostridium difficile carries three bclA genes. Using insertional mutagenesis each gene was characterized and spores devoid of these proteins had surface aberrations, reduced hydrophobicity and germinated faster than wild-type spores. Therefore the BclA proteins were likely major components of the spore surface and when absent impaired the protective shield effect of this outermost layer. Analysis of infection and colonization in mice and hamsters revealed that the 50% infectious dose (ID50 ) of spores was significantly higher (2-logs) in the bclA1(-) mutant compared to the isogenic wild-type control, but that levels of toxins (A and B) were indistinguishable from animals dosed with wild-type spores. bclA1(-) spores germinated faster than wild-type spores yet mice were less susceptible to infection suggesting that BclA1 must play a key role in the initial (i.e. pre-spore germination) stages of infection. We also show that the ID50 was higher in mice infected with R20291, a 'hypervirulent' 027 strain, that carries a truncated BclA1 protein.
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Affiliation(s)
- Jutarop Phetcharaburanin
- School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, TW20 0EX, UK
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12
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Dembek M, Stabler RA, Witney AA, Wren BW, Fairweather NF. Transcriptional analysis of temporal gene expression in germinating Clostridium difficile 630 endospores. PLoS One 2013; 8:e64011. [PMID: 23691138 PMCID: PMC3655068 DOI: 10.1371/journal.pone.0064011] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 04/08/2013] [Indexed: 01/05/2023] Open
Abstract
Clostridium difficile is the leading cause of hospital acquired diarrhoea in industrialised countries. Under conditions that are not favourable for growth, the pathogen produces metabolically dormant endospores via asymmetric cell division. These are extremely resistant to both chemical and physical stress and provide the mechanism by which C. difficile can evade the potentially fatal consequences of exposure to heat, oxygen, alcohol, and certain disinfectants. Spores are the primary infective agent and must germinate to allow for vegetative cell growth and toxin production. While spore germination in Bacillus is well understood, little is known about C. difficile germination and outgrowth. Here we use genome-wide transcriptional analysis to elucidate the temporal gene expression patterns in C. difficile 630 endospore germination. We have optimized methods for large scale production and purification of spores. The germination characteristics of purified spores have been characterized and RNA extraction protocols have been optimized. Gene expression was highly dynamic during germination and outgrowth, and was found to involve a large number of genes. Using this genome-wide, microarray approach we have identified 511 genes that are significantly up- or down-regulated during C. difficile germination (p≤0.01). A number of functional groups of genes appeared to be co-regulated. These included transport, protein synthesis and secretion, motility and chemotaxis as well as cell wall biogenesis. These data give insight into how C. difficile re-establishes its metabolism, re-builds the basic structures of the vegetative cell and resumes growth.
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Affiliation(s)
- Marcin Dembek
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, United Kingdom
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13
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Povelones ML, Gluenz E, Dembek M, Gull K, Rudenko G. Histone H1 plays a role in heterochromatin formation and VSG expression site silencing in Trypanosoma brucei. PLoS Pathog 2012; 8:e1003010. [PMID: 23133390 PMCID: PMC3486875 DOI: 10.1371/journal.ppat.1003010] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Accepted: 09/20/2012] [Indexed: 11/30/2022] Open
Abstract
The African sleeping sickness parasite Trypanosoma brucei evades the host immune system through antigenic variation of its variant surface glycoprotein (VSG) coat. Although the T. brucei genome contains ∼1500 VSGs, only one VSG is expressed at a time from one of about 15 subtelomeric VSG expression sites (ESs). For antigenic variation to work, not only must the vast VSG repertoire be kept silent in a genome that is mainly constitutively transcribed, but the frequency of VSG switching must be strictly controlled. Recently it has become clear that chromatin plays a key role in silencing inactive ESs, thereby ensuring monoallelic expression of VSG. We investigated the role of the linker histone H1 in chromatin organization and ES regulation in T. brucei. T. brucei histone H1 proteins have a different domain structure to H1 proteins in higher eukaryotes. However, we show that they play a key role in the maintenance of higher order chromatin structure in bloodstream form T. brucei as visualised by electron microscopy. In addition, depletion of histone H1 results in chromatin becoming generally more accessible to endonucleases in bloodstream but not in insect form T. brucei. The effect on chromatin following H1 knock-down in bloodstream form T. brucei is particularly evident at transcriptionally silent ES promoters, leading to 6–8 fold derepression of these promoters. T. brucei histone H1 therefore appears to be important for the maintenance of repressed chromatin in bloodstream form T. brucei. In particular H1 plays a role in downregulating silent ESs, arguing that H1-mediated chromatin functions in antigenic variation in T. brucei. Trypanosoma brucei causes African sleeping sickness, endemic to sub-Saharan Africa. Bloodstream form T. brucei is covered with a dense coat of variant surface glycoprotein (VSG). Only one VSG is expressed at a time out of a vast repertoire of ∼1500 VSGs. The active VSG is transcribed in a telomeric VSG expression site (ES), and VSG switching allows immune evasion. Exactly how monoallelic exclusion of VSG ESs operates, and how switching between ESs is mediated remains mysterious, although epigenetics and chromatin structure clearly play a major role. The linker histone H1 is thought to orchestrate higher order chromatin structure in eukaryotes, but its exact function is unclear. We investigated the role of histone H1 in the regulation of antigenic variation in T. brucei. We show that histone H1 is associated with chromatin and is required for higher order chromatin structure. Depletion of histone H1 results in derepression of silent VSG ES promoters, indicating that H1-mediated chromatin functions in antigenic variation in T. brucei.
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Affiliation(s)
- Megan L. Povelones
- Division of Cell and Molecular Biology, Imperial College London, South Kensington, London, United Kingdom
| | - Eva Gluenz
- The Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Marcin Dembek
- Division of Cell and Molecular Biology, Imperial College London, South Kensington, London, United Kingdom
| | - Keith Gull
- The Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Gloria Rudenko
- Division of Cell and Molecular Biology, Imperial College London, South Kensington, London, United Kingdom
- * E-mail:
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14
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Abstract
Clostridium difficile infection is a leading cause of antibiotic-associated diarrhea, placing considerable economic pressure on healthcare systems and resulting in significant morbidity and mortality. The pathogen produces a proteinaceous array on its cell surface known as the S-layer, consisting primarily of the major S-layer protein SlpA and a family of SlpA homologs. CwpV is the largest member of this family and is expressed in a phase-variable manner. The protein is post-translationally processed into two fragments that form a noncovalent, heterodimeric complex. To date, no specific proteases capable of cleaving CwpV have been identified. Using site-directed mutagenesis we show that CwpV undergoes intramolecular autoproteolysis, most likely facilitated by a N-O acyl shift, with Thr-413 acting as the source of a nucleophile driving this rearrangement. We demonstrate that neighboring residues are also important for correct processing of CwpV. Based on protein structural predictions and analogy to the glycosylasparaginase family of proteins, it appears likely that these residues play key roles in determining the correct protein fold and interact directly with Thr-413 to promote nucleophilic attack. Furthermore, using a cell-free protein synthesis assay we show that CwpV maturation requires neither cofactors nor auxiliary enzymes.
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Affiliation(s)
- Marcin Dembek
- Division of Cell and Molecular Biology, Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, United Kingdom
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15
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Hinc K, Isticato R, Dembek M, Karczewska J, Iwanicki A, Peszyńska-Sularz G, De Felice M, Obuchowski M, Ricca E. Expression and display of UreA of Helicobacter acinonychis on the surface of Bacillus subtilis spores. Microb Cell Fact 2010; 9:2. [PMID: 20082702 PMCID: PMC2841587 DOI: 10.1186/1475-2859-9-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 01/18/2010] [Indexed: 01/02/2023] Open
Abstract
Background The bacterial endospore (spore) has recently been proposed as a new surface display system. Antigens and enzymes have been successfully exposed on the surface layers of the Bacillus subtilis spore, but only in a few cases the efficiency of expression and the effective surface display and have been determined. We used this heterologous expression system to produce the A subunit of the urease of the animal pathogen Helicobater acinonychis. Ureases are multi-subunit enzymes with a central role in the virulence of various bacterial pathogens and necessary for colonization of the gastric mucosa by the human pathogen H. pylori. The urease subunit UreA has been recognized as a major antigen, able to induce high levels of protection against challenge infections. Results We expressed UreA from H. acinonychis on the B. subtilis spore coat by using three different spore coat proteins as carriers and compared the efficiency of surface expression and surface display obtained with the three carriers. A combination of western-, dot-blot and immunofluorescence microscopy allowed us to conclude that, when fused to CotB, UreA is displayed on the spore surface (ca. 1 × 103 recombinant molecules per spore), whereas when fused to CotC, although most efficiently expressed (7-15 × 103 recombinant molecules per spore) and located in the coat layer, it is not displayed on the surface. Experiments with CotG gave results similar to those with CotC, but the CotG-UreA recombinant protein appeared to be partially processed. Conclusion UreA was efficiently expressed on the spore coat of B. subtilis when fused to CotB, CotC or CotG. Of these three coat proteins CotC allows the highest efficiency of expression, whereas CotB is the most appropriate for the display of heterologous proteins on the spore surface.
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Affiliation(s)
- Krzysztof Hinc
- Department of Structural and Functional Biology, Federico II University of Naples, via Cinthia 4, Naples 80126, Italy
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