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Adcox HE, Hunt JR, Allen PE, Siff TE, Rodino KG, Ottens AK, Carlyon JA. Orientia tsutsugamushi Ank5 promotes NLRC5 cytoplasmic retention and degradation to inhibit MHC class I expression. Nat Commun 2024; 15:8069. [PMID: 39277599 PMCID: PMC11401901 DOI: 10.1038/s41467-024-52119-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 08/27/2024] [Indexed: 09/17/2024] Open
Abstract
How intracellular bacteria subvert the major histocompatibility complex (MHC) class I pathway is poorly understood. Here, we show that the obligate intracellular bacterium Orientia tsutsugamushi uses its effector protein, Ank5, to inhibit nuclear translocation of the MHC class I gene transactivator, NLRC5, and orchestrate its proteasomal degradation. Ank5 uses a tyrosine in its fourth ankyrin repeat to bind the NLRC5 N-terminus while its F-box directs host SCF complex ubiquitination of NLRC5 in the leucine-rich repeat region that dictates susceptibility to Orientia- and Ank5-mediated degradation. The ability of O. tsutsugamushi strains to degrade NLRC5 correlates with ank5 genomic carriage. Ectopically expressed Ank5 that can bind but not degrade NLRC5 protects the transactivator during Orientia infection. Thus, Ank5 is an immunoevasin that uses its bipartite architecture to rid host cells of NLRC5 and reduce surface MHC class I molecules. This study offers insight into how intracellular pathogens can impair MHC class I expression.
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Affiliation(s)
- Haley E Adcox
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, School of Medicine, Charlottesville, VA, USA
| | - Jason R Hunt
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Paige E Allen
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Thomas E Siff
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Kyle G Rodino
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrew K Ottens
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Jason A Carlyon
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA.
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2
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Khaled N, Kulkarni RR, Käser T, Gimeno IM. Temporal Changes in Splenic Immune Cell Populations following Infection with a Very Virulent plus MDV in Commercial Meat-Type Chickens. Viruses 2024; 16:1092. [PMID: 39066253 PMCID: PMC11281429 DOI: 10.3390/v16071092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2024] [Revised: 07/02/2024] [Accepted: 07/04/2024] [Indexed: 07/28/2024] Open
Abstract
Marek's disease virus (MDV) can cause severe immunosuppression in chickens. Our previous study showed that infection with very virulent plus (vv+) MDV strains of one-day-old commercial meat-type chickens possessing maternal antibodies against MDV resulted in severe depletion of splenocytes at 28-30 days of age. In the present study, we have investigated the effect of vv+MDV strain 686 on splenic immunophenotypes at 6, 20, and 30 days post-infection (dpi). Both live and dead cells were analyzed, and the data were statistically compared to the uninfected control. The results revealed a decrease in the total live cell population starting on day 20, primarily affecting B cells, CD8β+, and gamma delta (γδ) T cells, while the frequencies of both live and dead CD3+ and CD4+ T cells were increased. The MHC-I expression of CD3+ and CD4+ T cells was higher at 20 and 30 dpi, while the expression of MHC-II on these cells was downregulated at 6 dpi but was upregulated at 30 dpi. Collectively, these results suggest that maternal antibodies seem to delay the negative effects of vv+MDV on the splenic lymphoid populations, albeit being non-protective. Our results emphasize the importance of MD vaccination in vv+MDV endemic areas.
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Affiliation(s)
- Nagwa Khaled
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA; (N.K.); (R.R.K.); (T.K.)
- Department of Virology, Faculty of Veterinary Medicine, University of Sadat City, Monofiya 23511, Egypt
| | - Raveendra R. Kulkarni
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA; (N.K.); (R.R.K.); (T.K.)
| | - Tobias Käser
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA; (N.K.); (R.R.K.); (T.K.)
| | - Isabel M. Gimeno
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA; (N.K.); (R.R.K.); (T.K.)
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3
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Cleaver J, Jeffery K, Klenerman P, Lim M, Handunnetthi L, Irani SR, Handel A. The immunobiology of herpes simplex virus encephalitis and post-viral autoimmunity. Brain 2024; 147:1130-1148. [PMID: 38092513 PMCID: PMC10994539 DOI: 10.1093/brain/awad419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/25/2023] [Accepted: 11/27/2023] [Indexed: 04/06/2024] Open
Abstract
Herpes simplex virus encephalitis (HSE) is the leading cause of non-epidemic encephalitis in the developed world and, despite antiviral therapy, mortality and morbidity is high. The emergence of post-HSE autoimmune encephalitis reveals a new immunological paradigm in autoantibody-mediated disease. A reductionist evaluation of the immunobiological mechanisms in HSE is crucial to dissect the origins of post-viral autoimmunity and supply rational approaches to the selection of immunotherapeutics. Herein, we review the latest evidence behind the phenotypic progression and underlying immunobiology of HSE including the cytokine/chemokine environment, the role of pathogen-recognition receptors, T- and B-cell immunity and relevant inborn errors of immunity. Second, we provide a contemporary review of published patients with post-HSE autoimmune encephalitis from a combined cohort of 110 patients. Third, we integrate novel mechanisms of autoimmunization in deep cervical lymph nodes to explore hypotheses around post-HSE autoimmune encephalitis and challenge these against mechanisms of molecular mimicry and others. Finally, we explore translational concepts where neuroglial surface autoantibodies have been observed with other neuroinfectious diseases and those that generate brain damage including traumatic brain injury, ischaemic stroke and neurodegenerative disease. Overall, the clinical and immunological landscape of HSE is an important and evolving field, from which precision immunotherapeutics could soon emerge.
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Affiliation(s)
- Jonathan Cleaver
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, UK
- Department of Neurology, John Radcliffe Hospital, Oxford University Hospitals, Oxford, OX3 9DU, UK
| | - Katie Jeffery
- Department of Microbiology, Oxford University Hospitals NHS Foundation Trust, Oxford, OX3 9DU, UK
- Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DU, UK
| | - Paul Klenerman
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, OX1 3SY, UK
- Translational Gastroenterology Unit, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 9DU, UK
| | - Ming Lim
- Children’s Neurosciences, Evelina London Children’s Hospital at Guy’s and St Thomas’ NHS Foundation Trust, London, SE1 7EH, UK
- Department Women and Children’s Health, School of Life Course Sciences, King’s College London, London, WC2R 2LS, UK
| | - Lahiru Handunnetthi
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, UK
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Sarosh R Irani
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, UK
- Department of Neurology, John Radcliffe Hospital, Oxford University Hospitals, Oxford, OX3 9DU, UK
| | - Adam Handel
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, UK
- Department of Neurology, John Radcliffe Hospital, Oxford University Hospitals, Oxford, OX3 9DU, UK
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Ware BC, Parks MG, da Silva MOL, Morrison TE. Chikungunya virus infection disrupts MHC-I antigen presentation via nonstructural protein 2. PLoS Pathog 2024; 20:e1011794. [PMID: 38483968 DOI: 10.1371/journal.ppat.1011794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 03/26/2024] [Accepted: 03/04/2024] [Indexed: 03/26/2024] Open
Abstract
Infection by chikungunya virus (CHIKV), a mosquito-borne alphavirus, causes severe polyarthralgia and polymyalgia, which can last in some people for months to years. Chronic CHIKV disease signs and symptoms are associated with the persistence of viral nucleic acid and antigen in tissues. Like humans and nonhuman primates, CHIKV infection in mice results in the development of robust adaptive antiviral immune responses. Despite this, joint tissue fibroblasts survive CHIKV infection and can support persistent viral replication, suggesting that they escape immune surveillance. Here, using a recombinant CHIKV strain encoding the fluorescent protein VENUS with an embedded CD8+ T cell epitope, SIINFEKL, we observed a marked loss of both MHC class I (MHC-I) surface expression and antigen presentation by CHIKV-infected joint tissue fibroblasts. Both in vivo and ex vivo infected joint tissue fibroblasts displayed reduced cell surface levels of H2-Kb and H2-Db MHC-I proteins while maintaining similar levels of other cell surface proteins. Mutations within the methyl transferase-like domain of the CHIKV nonstructural protein 2 (nsP2) increased MHC-I cell surface expression and antigen presentation efficiency by CHIKV-infected cells. Moreover, expression of WT nsP2 alone, but not nsP2 with mutations in the methyltransferase-like domain, resulted in decreased MHC-I antigen presentation efficiency. MHC-I surface expression and antigen presentation was rescued by replacing VENUS-SIINFEKL with SIINFEKL tethered to β2-microglobulin in the CHIKV genome, which bypasses the requirement for peptide processing and TAP-mediated peptide transport into the endoplasmic reticulum. Collectively, this work suggests that CHIKV escapes the surveillance of antiviral CD8+ T cells, in part, by nsP2-mediated disruption of MHC-I antigen presentation.
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Affiliation(s)
- Brian C Ware
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - M Guston Parks
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Mariana O L da Silva
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
- Instituto de Microbiologia Paulo de Goes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thomas E Morrison
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
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Meng X, Ma F, Yu D. The diverse effects of cisplatin on tumor microenvironment: Insights and challenges for the delivery of cisplatin by nanoparticles. ENVIRONMENTAL RESEARCH 2024; 240:117362. [PMID: 37827371 DOI: 10.1016/j.envres.2023.117362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 09/11/2023] [Accepted: 10/09/2023] [Indexed: 10/14/2023]
Abstract
Cisplatin is a well-known platinum-based chemotherapy medication that is widely utilized for some malignancies. Despite the direct cytotoxic consequences of cisplatin on tumor cells, studies in the recent decade have revealed that cisplatin can also affect different cells and their secretions in the tumor microenvironment (TME). Cisplatin has complex impacts on the TME, which may contribute to its anti-tumor activity or drug resistance mechanisms. These regulatory effects of cisplatin play a paramount function in tumor growth, invasion, and metastasis. This paper aims to review the diverse impacts of cisplatin and nanoparticles loaded with cisplatin on cancer cells and also non-cancerous cells in TME. The impacts of cisplatin on immune cells, tumor stroma, cancer cells, and also hypoxia will be discussed in the current review. Furthermore, we emphasize the challenges and prospects of using cisplatin in combination with other adjuvants and therapeutic modalities that target TME. We also discuss the potential synergistic effects of cisplatin with immune checkpoint inhibitors (ICIs) and other agents with anticancer potentials such as polyphenols and photosensitizers. Furthermore, the potential of nanoparticles for targeting TME and better delivery of cisplatin into tumors will be discussed.
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Affiliation(s)
- Xinxin Meng
- Zhuji Sixth People's Hospital of Zhejiang Province, Zhuji, Zhejiang, 311801, China
| | - Fengyun Ma
- Zhuji People's Hospital of Zhejiang Province, Zhuji Affiliated Hospital of Shaoxing University, Zhuji, Zhejiang, 311800, China.
| | - Dingli Yu
- Zhuji People's Hospital of Zhejiang Province, Zhuji Affiliated Hospital of Shaoxing University, Zhuji, Zhejiang, 311800, China
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Ware BC, Parks MG, Morrison TE. Chikungunya virus infection disrupts MHC-I antigen presentation via nonstructural protein 2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.03.565436. [PMID: 37961400 PMCID: PMC10635105 DOI: 10.1101/2023.11.03.565436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Infection by chikungunya virus (CHIKV), a mosquito-borne alphavirus, causes severe polyarthralgia and polymyalgia, which can last in some people for months to years. Chronic CHIKV disease signs and symptoms are associated with the persistence of viral nucleic acid and antigen in tissues. Like humans and nonhuman primates, CHIKV infection in mice results in the development of robust adaptive antiviral immune responses. Despite this, joint tissue fibroblasts survive CHIKV infection and can support persistent viral replication, suggesting that they escape immune surveillance. Here, using a recombinant CHIKV strain encoding a chimeric protein of VENUS fused to a CD8+ T cell epitope, SIINFEKL, we observed a marked loss of both MHC class I (MHC-I) surface expression and antigen presentation by CHIKV-infected joint tissue fibroblasts. Both in vivo and ex vivo infected joint tissue fibroblasts displayed reduced cell surface levels of H2-Kb and H2-Db MHC proteins while maintaining similar levels of other cell surface proteins. Mutations within the methyl transferase-like domain of the CHIKV nonstructural protein 2 (nsP2) increased MHC-I cell surface expression and antigen presentation efficiency by CHIKV-infected cells. Moreover, expression of WT nsP2 alone, but not nsP2 with mutations in the methyltransferase-like domain, resulted in decreased MHC-I antigen presentation efficiency. MHC-I surface expression and antigen presentation could be rescued by replacing VENUS-SIINFEKL with SIINFEKL tethered to β2-microglobulin in the CHIKV genome, which bypasses the need for peptide processing and TAP-mediated peptide transport into the endoplasmic reticulum. Collectively, this work suggests that CHIKV escapes the surveillance of antiviral CD8+ T cells, in part, by nsP2-mediated disruption of MHC-I antigen presentation.
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Affiliation(s)
- Brian C. Ware
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - M. Guston Parks
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Thomas E. Morrison
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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7
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Malviya M, Aretz Z, Molvi Z, Lee J, Pierre S, Wallisch P, Dao T, Scheinberg DA. Challenges and solutions for therapeutic TCR-based agents. Immunol Rev 2023; 320:58-82. [PMID: 37455333 PMCID: PMC11141734 DOI: 10.1111/imr.13233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 06/18/2023] [Indexed: 07/18/2023]
Abstract
Recent development of methods to discover and engineer therapeutic T-cell receptors (TCRs) or antibody mimics of TCRs, and to understand their immunology and pharmacology, lag two decades behind therapeutic antibodies. Yet we have every expectation that TCR-based agents will be similarly important contributors to the treatment of a variety of medical conditions, especially cancers. TCR engineered cells, soluble TCRs and their derivatives, TCR-mimic antibodies, and TCR-based CAR T cells promise the possibility of highly specific drugs that can expand the scope of immunologic agents to recognize intracellular targets, including mutated proteins and undruggable transcription factors, not accessible by traditional antibodies. Hurdles exist regarding discovery, specificity, pharmacokinetics, and best modality of use that will need to be overcome before the full potential of TCR-based agents is achieved. HLA restriction may limit each agent to patient subpopulations and off-target reactivities remain important barriers to widespread development and use of these new agents. In this review we discuss the unique opportunities for these new classes of drugs, describe their unique antigenic targets, compare them to traditional antibody therapeutics and CAR T cells, and review the various obstacles that must be overcome before full application of these drugs can be realized.
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Affiliation(s)
- Manish Malviya
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
| | - Zita Aretz
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
- Physiology, Biophysics & Systems Biology Program, Weill Cornell Graduate School of Medical Sciences, 1300 York Avenue, New York, NY 10021
| | - Zaki Molvi
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
- Physiology, Biophysics & Systems Biology Program, Weill Cornell Graduate School of Medical Sciences, 1300 York Avenue, New York, NY 10021
| | - Jayop Lee
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
| | - Stephanie Pierre
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
- Tri-Institutional Medical Scientist Program, 1300 York Avenue, New York, NY 10021
| | - Patrick Wallisch
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
- Pharmacology Program, Weill Cornell Graduate School of Medical Sciences, 1300 York Avenue, New York, NY 10021
| | - Tao Dao
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
| | - David A. Scheinberg
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065
- Pharmacology Program, Weill Cornell Graduate School of Medical Sciences, 1300 York Avenue, New York, NY 10021
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Cruz FM, Chan A, Rock KL. Pathways of MHC I cross-presentation of exogenous antigens. Semin Immunol 2023; 66:101729. [PMID: 36804685 PMCID: PMC10023513 DOI: 10.1016/j.smim.2023.101729] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 02/02/2023] [Accepted: 02/02/2023] [Indexed: 02/18/2023]
Abstract
Phagocytes, particularly dendritic cells (DCs), generate peptide-major histocompatibility complex (MHC) I complexes from antigens they have collected from cells in tissues and report this information to CD8 T cells in a process called cross-presentation. This process allows CD8 T cells to detect, respond and eliminate abnormal cells, such as cancers or cells infected with viruses or intracellular microbes. In some settings, cross-presentation can help tolerize CD8 T cells to self-antigens. One of the principal ways that DCs acquire tissue antigens is by ingesting this material through phagocytosis. The resulting phagosomes are key hubs in the cross-presentation (XPT) process and in fact experimentally conferring the ability to phagocytize antigens can be sufficient to allow non-professional antigen presenting cells (APCs) to cross-present. Once in phagosomes, exogenous antigens can be cross-presented (XPTed) through three distinct pathways. There is a vacuolar pathway in which peptides are generated and then bind to MHC I molecules within the confines of the vacuole. Ingested exogenous antigens can also be exported from phagosomes to the cytosol upon vesicular rupture and/or possibly transport. Once in the cytosol, the antigen is degraded by the proteasome and the resulting oligopeptides can be transported to MHC I molecule in the endoplasmic reticulum (ER) (a phagosome-to-cytosol (P2C) pathway) or in phagosomes (a phagosome-to-cytosol-to-phagosome (P2C2P) pathway). Here we review how phagosomes acquire the necessary molecular components that support these three mechanisms and the contribution of these pathways. We describe what is known as well as the gaps in our understanding of these processes.
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Affiliation(s)
- Freidrich M Cruz
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Amanda Chan
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Kenneth L Rock
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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Cooper A, Sidaway A, Chandrashekar A, Latta E, Chakraborty K, Yu J, McMahan K, Giffin V, Manickam C, Kroll K, Mosher M, Reeves RK, Gam R, Arthofer E, Choudhry M, Henley T, Barouch DH. A genetically engineered, stem-cell-derived cellular vaccine. Cell Rep Med 2022; 3:100843. [PMID: 36480934 PMCID: PMC9727836 DOI: 10.1016/j.xcrm.2022.100843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 10/19/2022] [Accepted: 11/10/2022] [Indexed: 12/12/2022]
Abstract
Despite rapid clinical translation of COVID-19 vaccines in response to the global pandemic, an opportunity remains for vaccine technology innovation to address current limitations and meet challenges of inevitable future pandemics. We describe a universal vaccine cell (UVC) genetically engineered to mimic natural physiological immunity induced upon viral infection of host cells. Cells engineered to express the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike as a representative viral antigen induce robust neutralizing antibodies in immunized non-human primates. Similar titers generated in this established non-human primate (NHP) model have translated into protective human neutralizing antibody levels in SARS-CoV-2-vaccinated individuals. Animals vaccinated with ancestral spike antigens and subsequently challenged with SARS-CoV-2 Delta variant in a heterologous challenge have an approximately 3 log decrease in viral subgenomic RNA in the lungs. This cellular vaccine is designed as a scalable cell line with a modular poly-antigenic payload, allowing for rapid, large-scale clinical manufacturing and use in an evolving viral variant environment.
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Affiliation(s)
| | | | - Abishek Chandrashekar
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | | | | | - Jingyou Yu
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Katherine McMahan
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Victoria Giffin
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Cordelia Manickam
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Kyle Kroll
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Matthew Mosher
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - R Keith Reeves
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Rihab Gam
- Intima Bioscience, Inc., New York, NY, USA
| | | | - Modassir Choudhry
- Praesidium Bioscience, Inc., New York, NY, USA; Intima Bioscience, Inc., New York, NY, USA
| | - Tom Henley
- Praesidium Bioscience, Inc., New York, NY, USA; Intima Bioscience, Inc., New York, NY, USA.
| | - Dan H Barouch
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard University, Cambridge, MA, USA.
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Inhibition of major histocompatibility complex-I antigen presentation by sarbecovirus ORF7a proteins. Proc Natl Acad Sci U S A 2022; 119:e2209042119. [PMID: 36136978 PMCID: PMC9573092 DOI: 10.1073/pnas.2209042119] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to CD8+ cytotoxic T cells. As part of a screen to elucidate biological activities associated with individual severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) viral proteins, we found that ORF7a reduced cell surface MHC-I levels by approximately fivefold. Nevertheless, in cells infected with SARS-CoV-2, surface MHC-I levels were reduced even in the absence of ORF7a, suggesting additional mechanisms of MHC-I down-regulation. ORF7a proteins from a sample of sarbecoviruses varied in their ability to induce MHC-I down-regulation and, unlike SARS-CoV-2, the ORF7a protein from SARS-CoV lacked MHC-I downregulating activity. A single amino acid at position 59 (T/F) that is variable among sarbecovirus ORF7a proteins governed the difference in MHC-I downregulating activity. SARS-CoV-2 ORF7a physically associated with the MHC-I heavy chain and inhibited the presentation of expressed antigen to CD8+ T cells. Specifically, ORF7a prevented the assembly of the MHC-I peptide loading complex and caused retention of MHC-I in the endoplasmic reticulum. The differential ability of ORF7a proteins to function in this way might affect sarbecovirus dissemination and persistence in human populations, particularly those with infection- or vaccine-elicited immunity.
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Zhang F, Zang T, Stevenson EM, Lei X, Copertino DC, Mota TM, Boucau J, Garcia-Beltran WF, Jones RB, Bieniasz PD. Inhibition of major histocompatibility complex-I antigen presentation by sarbecovirus ORF7a proteins. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022. [PMID: 35665005 PMCID: PMC9164438 DOI: 10.1101/2022.05.25.493467] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to CD8+ cytotoxic T cells. As part of a screen to elucidate biological activities associated with individual SARS-CoV-2 viral proteins, we found that ORF7a reduced cell surface MHC-I levels by approximately 5-fold. Nevertheless, in cells infected with SARS-CoV-2, surface MHC-I levels were reduced even in the absence of ORF7a, suggesting additional mechanisms of MHC-I downregulation. ORF7a proteins from a sample of sarbecoviruses varied in their ability to induce MHC-I downregulation and, unlike SARS-CoV-2, the ORF7a protein from SARS-CoV lacked MHC-I downregulating activity. A single-amino acid at position 59 (T/F) that is variable among sarbecovirus ORF7a proteins governed the difference in MHC-I downregulating activity. SARS-CoV-2 ORF7a physically associated with the MHC-I heavy chain and inhibited the presentation of expressed antigen to CD8+ T-cells. Speficially, ORF7a prevented the assembly of the MHC-I peptide loading complex and causing retention of MHC-I in the endoplasmic reticulum. The differential ability of ORF7a proteins to function in this way might affect sarbecovirus dissemination and persistence in human populations, particularly those with infection- or vaccine-elicited immunity.
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12
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Hensen L, Illing PT, Rowntree LC, Davies J, Miller A, Tong SYC, Habel JR, van de Sandt CE, Flanagan K, Purcell AW, Kedzierska K, Clemens EB. T Cell Epitope Discovery in the Context of Distinct and Unique Indigenous HLA Profiles. Front Immunol 2022; 13:812393. [PMID: 35603215 PMCID: PMC9121770 DOI: 10.3389/fimmu.2022.812393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
CD8+ T cells are a pivotal part of the immune response to viruses, playing a key role in disease outcome and providing long-lasting immunity to conserved pathogen epitopes. Understanding CD8+ T cell immunity in humans is complex due to CD8+ T cell restriction by highly polymorphic Human Leukocyte Antigen (HLA) proteins, requiring T cell epitopes to be defined for different HLA allotypes across different ethnicities. Here we evaluate strategies that have been developed to facilitate epitope identification and study immunogenic T cell responses. We describe an immunopeptidomics approach to sequence HLA-bound peptides presented on virus-infected cells by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Using antigen presenting cell lines that stably express the HLA alleles characteristic of Indigenous Australians, this approach has been successfully used to comprehensively identify influenza-specific CD8+ T cell epitopes restricted by HLA allotypes predominant in Indigenous Australians, including HLA-A*24:02 and HLA-A*11:01. This is an essential step in ensuring high vaccine coverage and efficacy in Indigenous populations globally, known to be at high risk from influenza disease and other respiratory infections.
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Affiliation(s)
- Luca Hensen
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Patricia T. Illing
- Department of Biochemistry and Molecular Biology & Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Louise C. Rowntree
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Jane Davies
- Menzies School of Health Research, Darwin, NT, Australia
| | - Adrian Miller
- Indigenous Engagement, CQUniversity, Townsville, QLD, Australia
| | - Steven Y. C. Tong
- Menzies School of Health Research, Darwin, NT, Australia
- Victorian Infectious Diseases Service, The Royal Melbourne Hospital at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Jennifer R. Habel
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Carolien E. van de Sandt
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
- Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Katie L. Flanagan
- Department of Infectious Diseases and Tasmanian Vaccine Trial Centre, Launceston General Hospital, Launceston, TAS, Australia
- School of Health Sciences and School of Medicine, University of Tasmania, Launceston, TAS, Australia
- Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia
- School of Health and Biomedical Science, RMIT University, Melbourne, VIC, Australia
| | - Anthony W. Purcell
- Department of Biochemistry and Molecular Biology & Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Katherine Kedzierska
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - E. Bridie Clemens
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
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13
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Abstract
Viruses are essentially, obligate intracellular parasites. They require a host to replicate their genetic material, spread to other cells, and eventually to other hosts. For humans, most viral infections are not considered lethal, regardless if at the cellular level, the virus can obliterate individual cells. Constant genomic mutations, (which can alter the antigenic content of viruses such as influenza or coronaviruses), zoonosis or immunosuppression/immunocompromisation, is when viruses achieve higher host mortality. Frequent examples of the severe consequenses of viral infection can be seen in children and the elderly. In most instances, the immune system will take a multifaceted approach in defending the host against viruses. Depending on the virus, the individual, and the point of entry, the immune system will initiate a robust response which involves multiple components. In this chapter, we expand on the total immune system, breaking it down to the two principal types: Innate and Adaptive Immunity, their different roles in viral recognition and clearance. Finally, how different viruses activate and evade different arms of the immune system.
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14
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Zhao X, Wu LZ, Ng EKY, Leow KWS, Wei Q, Gascoigne NRJ, Brzostek J. Non-Stimulatory pMHC Enhance CD8 T Cell Effector Functions by Recruiting Coreceptor-Bound Lck. Front Immunol 2021; 12:721722. [PMID: 34707605 PMCID: PMC8542885 DOI: 10.3389/fimmu.2021.721722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 09/20/2021] [Indexed: 11/17/2022] Open
Abstract
Under physiological conditions, CD8+ T cells need to recognize low numbers of antigenic pMHC class I complexes in the presence of a surplus of non-stimulatory, self pMHC class I on the surface of the APC. Non-stimulatory pMHC have been shown to enhance CD8+ T cell responses to low amounts of antigenic pMHC, in a phenomenon called co-agonism, but the physiological significance and molecular mechanism of this phenomenon are still poorly understood. Our data show that co-agonist pMHC class I complexes recruit CD8-bound Lck to the immune synapse to modulate CD8+ T cell signaling pathways, resulting in enhanced CD8+ T cell effector functions and proliferation, both in vitro and in vivo. Moreover, co-agonism can boost T cell proliferation through an extrinsic mechanism, with co-agonism primed CD8+ T cells enhancing Akt pathway activation and proliferation in neighboring CD8+ T cells primed with low amounts of antigen.
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Affiliation(s)
- Xiang Zhao
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Liang-Zhe Wu
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Esther K Y Ng
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Kerisa W S Leow
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Qianru Wei
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Nicholas R J Gascoigne
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Joanna Brzostek
- Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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15
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Padariya M, Kote S, Mayordomo M, Dapic I, Alfaro J, Hupp T, Fahraeus R, Kalathiya U. Structural determinants of peptide-dependent TAP1-TAP2 transit passage targeted by viral proteins and altered by cancer-associated mutations. Comput Struct Biotechnol J 2021; 19:5072-5091. [PMID: 34589184 PMCID: PMC8453138 DOI: 10.1016/j.csbj.2021.09.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 09/06/2021] [Accepted: 09/06/2021] [Indexed: 01/20/2023] Open
Abstract
The TAP1-TAP2 complex transports antigenic peptide substrates into the endoplasmic reticulum (ER). In ER, the peptides are further processed and loaded on the major histocompatibility class (MHC) I molecules by the peptide loading complex (PLC). The TAP transporters are linked with the PLC; a target for cancers and viral immune evasion. But the mechanisms whereby the cancer-derived mutations in TAP1-TAP2 or viral factors targeting the PLC, interfere peptide transport are only emerging. This study describes that transit of peptides through TAP can take place via two different channels (4 or 8 helices) depending on peptide length and sequence. Molecular dynamics and binding affinity predictions of peptide-transporters demonstrated that smaller peptides (8-10 mers; e.g. AAGIGILTV, SIINFEKL) can transport quickly through the transport tunnel compared to longer peptides (15-mer; e.g. ENPVVHFFKNIVTPR). In line with a regulated and selective peptide transport by TAPs, the immunopeptidome upon IFN-γ treatment in melanoma cells induced the shorter length (9-mer) peptide presentation over MHC-I that exhibit a relatively weak binding affinity with TAP. A conserved distance between N and C terminus residues of the studied peptides in the transport tunnel were reported. Furthermore, by adversely interacting with the TAP transport passage or affecting TAPNBD domains tilt movement, the viral proteins and cancer-derived mutations in TAP1-TAP2 may induce allosteric effects in TAP that block conformation of the tunnel (closed towards ER lumen). Interestingly, some cancer-associated mutations (e.g. TAP1R372Q and TAP2R373H) can specifically interfere with selective transport channels (i.e. for longer-peptides). These results provide a model for how viruses and cancer-associated mutations targeting TAP interfaces can affect MHC-I antigen presentation, and how the IFN-γ pathway alters MHC-I antigen presentation via the kinetics of peptide transport.
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Affiliation(s)
- Monikaben Padariya
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
| | - Sachin Kote
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
| | - Marcos Mayordomo
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
| | - Irena Dapic
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
| | - Javier Alfaro
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
- Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, Scotland EH4 2XR, United Kingdom
| | - Ted Hupp
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
- Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, Scotland EH4 2XR, United Kingdom
| | - Robin Fahraeus
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France
- Department of Medical Biosciences, Building 6M, Umeå University, 901 85 Umeå, Sweden
- RECAMO, Masaryk Memorial Cancer Institute, Zlutykopec 7, 65653 Brno, Czech Republic
| | - Umesh Kalathiya
- International Centre for Cancer Vaccine Science, University of Gdansk, ul. Kładki 24, 80-822 Gdansk, Poland
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16
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Dersh D, Yewdell JW. Immune MAL2-practice: breast cancer immunoevasion via MHC class I degradation. J Clin Invest 2021; 131:144344. [PMID: 33393509 DOI: 10.1172/jci144344] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The success of tumor immunotherapy, while partial, confirms the existence and importance of tumor immunosurveillance. CD8+ T cell recognition of tumor-specific peptides bound to MHC class I (MHC-I) molecules is central to this process. In this issue of the JCI, Fang, Wang, et al. describe a unique tumor immunoevasion strategy based on endocytosis and degradation of MHC-I complexes mediated by the trafficking factor MAL2. Notably, MAL2 expression was associated with poor prognosis of breast cancer, and its downregulation enhanced CD8+ T cell recognition of breast cancer in various experimental models. This work demonstrates that a deeper understanding of tumor interference with MHC-I stability and trafficking has considerable potential for enhancing immunotherapies.
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17
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Tsutsumi N, Qu Q, Mavri M, Baggesen MS, Maeda S, Waghray D, Berg C, Kobilka BK, Rosenkilde MM, Skiniotis G, Garcia KC. Structural basis for the constitutive activity and immunomodulatory properties of the Epstein-Barr virus-encoded G protein-coupled receptor BILF1. Immunity 2021; 54:1405-1416.e7. [PMID: 34216564 DOI: 10.1016/j.immuni.2021.06.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 03/21/2021] [Accepted: 06/01/2021] [Indexed: 12/22/2022]
Abstract
Epstein-Barr virus (EBV) encodes a G protein-coupled receptor (GPCR) termed BILF1 that is essential for EBV-mediated immunosuppression and oncogenesis. BILF1 couples with inhibitory G protein (Gi), the major intracellular signaling effector for human chemokine receptors, and exhibits constitutive signaling activity; the ligand(s) for BILF1 are unknown. We studied the origins of BILF1's constitutive activity through structure determination of BILF1 bound to the inhibitory G protein (Gi) heterotrimer. The 3.2-Å resolution cryo-electron microscopy structure revealed an extracellular loop within BILF1 that blocked the typical chemokine binding site, suggesting ligand-autonomous receptor activation. Rather, amino acid substitutions within BILF1 transmembrane regions at hallmark ligand-activated class A GPCR "microswitches" stabilized a constitutively active BILF1 conformation for Gi coupling in a ligand-independent fashion. Thus, the constitutive activity of BILF1 promotes immunosuppression and virulence independent of ligand availability, with implications for the function of GPCRs encoded by related viruses and for therapeutic targeting of EBV.
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Affiliation(s)
- Naotaka Tsutsumi
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA; Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Qianhui Qu
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA; Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Maša Mavri
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark; Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Maibritt S Baggesen
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Shoji Maeda
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Deepa Waghray
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Christian Berg
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Brian K Kobilka
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Georgios Skiniotis
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA; Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - K Christopher Garcia
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA; Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA.
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18
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Aflalo A, Boyle LH. Polymorphisms in MHC class I molecules influence their interactions with components of the antigen processing and presentation pathway. Int J Immunogenet 2021; 48:317-325. [PMID: 34176210 DOI: 10.1111/iji.12546] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/12/2021] [Accepted: 05/24/2021] [Indexed: 10/21/2022]
Abstract
MHC class I (MHC-I) molecules undergo an intricate folding process in order to pick up antigenic peptide to present to the immune system. In recent years, the discovery of a new peptide editor for MHC-I has added an extra level of complexity in our understanding of how peptide presentation is regulated. On top of this, the incredible diversity in MHC-I molecules leads to significant variation in the interaction between MHC-I and components of the antigen processing and presentation pathway. Here, we review our current understanding regarding how polymorphisms in human leukocyte antigen class I molecules influence their interactions with key components of the antigen processing and presentation pathway. A deeper understanding of this may offer new insights regarding how apparently subtle variation in MHC-I can have a significant impact on susceptibility to disease.
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Affiliation(s)
- Aure Aflalo
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Louise H Boyle
- Department of Pathology, University of Cambridge, Cambridge, UK
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19
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Piersma SJ, Brizić I. Natural killer cell effector functions in antiviral defense. FEBS J 2021; 289:3982-3999. [PMID: 34125493 DOI: 10.1111/febs.16073] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/27/2021] [Accepted: 06/14/2021] [Indexed: 11/27/2022]
Abstract
Natural killer (NK) cells are innate lymphoid cells involved in the control of tumors and viral infections. They provide protection by producing cytokines and by directly lysing target cells. Both effector mechanisms have been identified to contribute to viral control, depending on the context of infection. Activation of NK cells depends on the integration of signals received by cytokine receptors and activation and inhibitory receptors recognizing ligands expressed by virus-infected cells. While the control of viral infections by NK cells is well established, the signals perceived by NK cells and how these signals integrate to mediate optimal viral control have been focus of ongoing research. Here, we discuss the current knowledge on NK cell activation and integration of signals that lead to interferon gamma production and cytotoxicity in viral infections. We review NK cell interactions with viruses, with particular focus on murine cytomegalovirus studies, which helped elucidate crucial aspects of antiviral NK cell immunity.
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Affiliation(s)
- Sytse J Piersma
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Ilija Brizić
- Center for Proteomics, Faculty of Medicine, University of Rijeka, Croatia
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20
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Komov L, Melamed Kadosh D, Barnea E, Admon A. The Effect of Interferons on Presentation of Defective Ribosomal Products as HLA Peptides. Mol Cell Proteomics 2021; 20:100105. [PMID: 34087483 PMCID: PMC8724922 DOI: 10.1016/j.mcpro.2021.100105] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 05/15/2021] [Accepted: 05/21/2021] [Indexed: 02/06/2023] Open
Abstract
A subset of class I major histocompatibility complex (MHC)-bound peptides is produced from immature proteins that are rapidly degraded after synthesis. These defective ribosomal products (DRiPs) have been implicated in early alert of the immune system about impending infections. Interferons are important cytokines, produced in response to viral infection, that modulate cellular metabolism and gene expression patterns, increase the presentation of MHC molecules, and induce rapid degradation of proteins and cell-surface presentation of their derived MHC peptides, thereby contributing to the battle against pathogen infections. This study evaluated the role of interferons in the induction of rapid degradation of DRiPs to modulate the repertoire of DRiP-derived MHC peptides. Cultured human breast cancer cells were treated with interferons, and the rates of synthesis and degradation of cellular protein and their degradation products were determined by LC-MS/MS analysis, following the rates of incorporation of heavy stable isotope–labeled amino acids (dynamic stable isotope labeling by amino acids in cell culture, dynamic SILAC) at several time points after the interferon application. Large numbers of MHC peptides that incorporated the heavy amino acids faster than their source proteins indicated that DRiP peptides were abundant in the MHC peptidome; interferon treatment increased by about twofold their relative proportions in the peptidome. Such typical DRiP-derived MHC peptides were from the surplus subunits of the proteasome and ribosome, which are degraded because of the transition to immunoproteasomes and a new composition of ribosomes incorporating protein subunits that are induced by the interferon. We conclude that degradation of surplus subunits induced by the interferon is a major source for DRiP–MHC peptides, a phenomenon relevant to coping with viral infections, where a rapid presentation of MHC peptides derived from excess viral proteins may help alert the immune system about the impending infection. Degradation products of surplus subunits are often presented as HLA peptides. Interferons increase degradation and presentation of such defective products. Dynamic SILAC facilitates identification of such HLA peptides. This cellular pathway provides alert to the immune system about viral infections.
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Affiliation(s)
- Liran Komov
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | | | - Eilon Barnea
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Arie Admon
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
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21
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Hafstrand I, Aflalo A, Boyle LH. Why TAPBPR? Implications of an additional player in MHC class I peptide presentation. Curr Opin Immunol 2021; 70:90-94. [PMID: 34052734 DOI: 10.1016/j.coi.2021.04.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/15/2021] [Accepted: 04/30/2021] [Indexed: 10/21/2022]
Abstract
The peptide editor TAPBPR is the newest member of the major histocompatibility complex class I (MHC-I) antigen processing and presentation pathway. Since 2013, studies have explored the functions and mechanisms of action of this tapasin homolog. Here, we review the key insights gained from structural studies of the TAPBPR:MHC-I complex and the involvement of the TAPBPR loop in peptide exchange. However, despite recent advances, the question still remains: why do we need TAPBPR? The recent appreciation that different MHC-I allotypes vary in their ability to interact with TAPBPR, together with a role for TAPBPR in alternative presentation pathways highlights that much remains unknown concerning the biological need for TAPBPR.
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Affiliation(s)
- Ida Hafstrand
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom; Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
| | - Aure Aflalo
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom
| | - Louise H Boyle
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom.
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22
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Regulation of the Macroautophagic Machinery, Cellular Differentiation, and Immune Responses by Human Oncogenic γ-Herpesviruses. Viruses 2021; 13:v13050859. [PMID: 34066671 PMCID: PMC8150893 DOI: 10.3390/v13050859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/05/2021] [Accepted: 05/06/2021] [Indexed: 11/21/2022] Open
Abstract
The human γ-herpesviruses Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV) encode oncogenes for B cell transformation but are carried by most infected individuals without symptoms. For this purpose, they manipulate the anti-apoptotic pathway macroautophagy, cellular proliferation and apoptosis, as well as immune recognition. The mechanisms and functional relevance of these manipulations are discussed in this review. They allow both viruses to strike the balance between efficient persistence and dissemination in their human hosts without ever being cleared after infection and avoiding pathologies in most of their carriers.
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23
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McSharry BP, Samer C, McWilliam HEG, Ashley CL, Yee MB, Steain M, Liu L, Fairlie DP, Kinchington PR, McCluskey J, Abendroth A, Villadangos JA, Rossjohn J, Slobedman B. Virus-Mediated Suppression of the Antigen Presentation Molecule MR1. Cell Rep 2021; 30:2948-2962.e4. [PMID: 32130899 PMCID: PMC7798347 DOI: 10.1016/j.celrep.2020.02.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 12/18/2019] [Accepted: 02/04/2020] [Indexed: 02/07/2023] Open
Abstract
The antigen-presenting molecule MR1 presents microbial metabolites related to vitamin B2 biosynthesis to mucosal-associated invariant T cells (MAIT cells). Although bacteria and fungi drive the MR1 biosynthesis pathway, viruses have not previously been implicated in MR1 expression or its antigen presentation. We demonstrate that several herpesviruses inhibit MR1 cell surface upregulation, including a potent inhibition by herpes simplex virus type 1 (HSV-1). This virus profoundly suppresses MR1 cell surface expression and targets the molecule for proteasomal degradation, whereas ligand-induced cell surface expression of MR1 prior to infection enables MR1 to escape HSV-1-dependent targeting. HSV-1 downregulation of MR1 is dependent on de novo viral gene expression, and we identify the Us3 viral gene product as functioning to target MR1. Furthermore, HSV-1 downregulation of MR1 disrupts MAIT T cell receptor (TCR) activation. Accordingly, virus-mediated targeting of MR1 defines an immunomodulatory strategy that functionally disrupts the MR1-MAIT TCR axis.
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Affiliation(s)
- Brian P McSharry
- Discipline of Infectious Diseases and Immunology, Faculty of Medicine and Health, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia; School of Microbiology, University College Cork, Cork, Ireland; APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Carolyn Samer
- Discipline of Infectious Diseases and Immunology, Faculty of Medicine and Health, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Hamish E G McWilliam
- Department of Microbiology and Immunology, The University of Melbourne, at The Peter Doherty Institute of Infection and Immunity, Melbourne, VIC, Australia; Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, Australia
| | - Caroline L Ashley
- Discipline of Infectious Diseases and Immunology, Faculty of Medicine and Health, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Michael B Yee
- Departments of Ophthalmology and of Molecular Microbiology and Genetics, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Megan Steain
- Discipline of Infectious Diseases and Immunology, Faculty of Medicine and Health, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Ligong Liu
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
| | - David P Fairlie
- ARC Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
| | - Paul R Kinchington
- Departments of Ophthalmology and of Molecular Microbiology and Genetics, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - James McCluskey
- Department of Microbiology and Immunology, The University of Melbourne, at The Peter Doherty Institute of Infection and Immunity, Melbourne, VIC, Australia
| | - Allison Abendroth
- Discipline of Infectious Diseases and Immunology, Faculty of Medicine and Health, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Jose A Villadangos
- Department of Microbiology and Immunology, The University of Melbourne, at The Peter Doherty Institute of Infection and Immunity, Melbourne, VIC, Australia; Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, VIC, Australia; Institute of Infection and Immunity, Cardiff University School of Medicine, Wales, UK
| | - Barry Slobedman
- Discipline of Infectious Diseases and Immunology, Faculty of Medicine and Health, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia.
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24
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The Role of NK Cells in EBV Infection and EBV-Associated NPC. Viruses 2021; 13:v13020300. [PMID: 33671917 PMCID: PMC7918975 DOI: 10.3390/v13020300] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 12/20/2022] Open
Abstract
A vast majority of the population worldwide are asymptomatic carriers of Epstein-Barr Virus (EBV). However, some infected individuals eventually develop EBV-related cancers, including Nasopharyngeal Carcinoma (NPC). NPC is one of the most common EBV-associated epithelial cancers, and is highly prevalent in Southern China and Southeast Asia. While NPC is highly sensitive to radiotherapy and chemotherapy, there is a lack of effective and durable treatment among the 15%–30% of patients who subsequently develop recurrent disease. Natural Killer (NK) cells are natural immune lymphocytes that are innately primed against virus-infected cells and nascent aberrant transformed cells. As EBV is found in both virally infected and cancer cells, it is of interest to examine the NK cells’ role in both EBV infection and EBV-associated NPC. Herein, we review the current understanding of how EBV-infected cells are cleared by NK cells, and how EBV can evade NK cell-mediated elimination in the context of type II latency in NPC. Next, we summarize the current literature about NPC and NK cell biology. Finally, we discuss the translational potential of NK cells in NPC. This information will deepen our understanding of host immune interactions with EBV-associated NPC and facilitate development of more effective NK-mediated therapies for NPC treatment.
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25
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Influenza A Virus Hemagglutinin and Other Pathogen Glycoprotein Interactions with NK Cell Natural Cytotoxicity Receptors NKp46, NKp44, and NKp30. Viruses 2021; 13:v13020156. [PMID: 33494528 PMCID: PMC7911750 DOI: 10.3390/v13020156] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/10/2021] [Accepted: 01/11/2021] [Indexed: 12/16/2022] Open
Abstract
Natural killer (NK) cells are part of the innate immunity repertoire, and function in the recognition and destruction of tumorigenic and pathogen-infected cells. Engagement of NK cell activating receptors can lead to functional activation of NK cells, resulting in lysis of target cells. NK cell activating receptors specific for non-major histocompatibility complex ligands are NKp46, NKp44, NKp30, NKG2D, and CD16 (also known as FcγRIII). The natural cytotoxicity receptors (NCRs), NKp46, NKp44, and NKp30, have been implicated in functional activation of NK cells following influenza virus infection via binding with influenza virus hemagglutinin (HA). In this review we describe NK cell and influenza A virus biology, and the interactions of influenza A virus HA and other pathogen lectins with NK cell natural cytotoxicity receptors (NCRs). We review concepts which intersect viral immunology, traditional virology and glycobiology to provide insights into the interactions between influenza virus HA and the NCRs. Furthermore, we provide expert opinion on future directions that would provide insights into currently unanswered questions.
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26
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Angulo G, Zeleznjak J, Martínez-Vicente P, Puñet-Ortiz J, Hengel H, Messerle M, Oxenius A, Jonjic S, Krmpotić A, Engel P, Angulo A. Cytomegalovirus restricts ICOSL expression on antigen-presenting cells disabling T cell co-stimulation and contributing to immune evasion. eLife 2021; 10:59350. [PMID: 33459589 PMCID: PMC7840182 DOI: 10.7554/elife.59350] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 01/15/2021] [Indexed: 12/14/2022] Open
Abstract
Viral infections are controlled, and very often cleared, by activated T lymphocytes. The inducible co-stimulator (ICOS) mediates its functions by binding to its ligand ICOSL, enhancing T-cell activation and optimal germinal center (GC) formation. Here, we show that ICOSL is heavily downmodulated during infection of antigen-presenting cells by different herpesviruses. We found that, in murine cytomegalovirus (MCMV), the immunoevasin m138/fcr-1 physically interacts with ICOSL, impeding its maturation and promoting its lysosomal degradation. This viral protein counteracts T-cell responses, in an ICOS-dependent manner, and limits virus control during the acute MCMV infection. Additionally, we report that blockade of ICOSL in MCMV-infected mice critically regulates the production of MCMV-specific antibodies due to a reduction of T follicular helper and GC B cells. Altogether, these findings reveal a novel mechanism evolved by MCMV to counteract adaptive immune surveillance, and demonstrates a role of the ICOS:ICOSL axis in the host defense against herpesviruses.
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Affiliation(s)
- Guillem Angulo
- Immunology Unit, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain
| | - Jelena Zeleznjak
- Center for Proteomics, Faculty of Medicine, University of Rijeka, Rijeka, Croatia.,Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Pablo Martínez-Vicente
- Immunology Unit, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Joan Puñet-Ortiz
- Immunology Unit, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Hartmut Hengel
- Institute of Virology, University Medical Center, Albert-Ludwigs-University Freiburg, Freiburg, Germany.,Faculty of Medicine, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Martin Messerle
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Annette Oxenius
- Institute of Microbiology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Stipan Jonjic
- Center for Proteomics, Faculty of Medicine, University of Rijeka, Rijeka, Croatia.,Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Astrid Krmpotić
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Pablo Engel
- Immunology Unit, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Ana Angulo
- Immunology Unit, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
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27
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Schuren A, Boer I, Bouma E, Van de Weijer M, Costa A, Hubel P, Pichlmair A, Lebbink R, Wiertz E. The UFM1 Pathway Impacts HCMV US2-Mediated Degradation of HLA Class I. Molecules 2021; 26:molecules26020287. [PMID: 33430125 PMCID: PMC7827699 DOI: 10.3390/molecules26020287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/22/2020] [Accepted: 12/22/2020] [Indexed: 11/16/2022] Open
Abstract
To prevent accumulation of misfolded proteins in the endoplasmic reticulum, chaperones perform quality control on newly translated proteins and redirect misfolded proteins to the cytosol for degradation by the ubiquitin-proteasome system. This pathway is called ER-associated protein degradation (ERAD). The human cytomegalovirus protein US2 induces accelerated ERAD of HLA class I molecules to prevent immune recognition of infected cells by CD8+ T cells. Using US2-mediated HLA-I degradation as a model for ERAD, we performed a genome-wide CRISPR/Cas9 library screen to identify novel cellular factors associated with ERAD. Besides the identification of known players such as TRC8, p97, and UBE2G2, the ubiquitin-fold modifier1 (UFM1) pathway was found to affect degradation of HLA-I. UFMylation is a post-translational modification resembling ubiquitination. Whereas we observe ubiquitination of HLA-I, no UFMylation was detected on HLA-I or several other proteins involved in degradation of HLA-I, suggesting that the UFM1 pathway impacts ERAD in a different manner than ubiquitin. Interference with the UFM1 pathway seems to specifically inhibit the ER-to-cytosol dislocation of HLA-I. In the absence of detectable UFMylation of HLA-I, UFM1 may contribute to US2-mediated HLA-I degradation by misdirecting protein sorting indirectly. Mass spectrometry analysis of US2-expressing cells showed that ribosomal proteins are a major class of proteins undergoing extensive UFMylation; the role of these changes in protein degradation may be indirect and remains to be established.
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Affiliation(s)
- A.B.C. Schuren
- Department of Medical Microbiology, University Medical Center Utrecht, Postbus 85500, 3508 GA Utrecht, The Netherlands; (A.B.C.S.); (I.G.J.B.); (E.M.B.); (M.L.v.d.W.); (A.I.C.)
| | - I.G.J. Boer
- Department of Medical Microbiology, University Medical Center Utrecht, Postbus 85500, 3508 GA Utrecht, The Netherlands; (A.B.C.S.); (I.G.J.B.); (E.M.B.); (M.L.v.d.W.); (A.I.C.)
| | - E.M. Bouma
- Department of Medical Microbiology, University Medical Center Utrecht, Postbus 85500, 3508 GA Utrecht, The Netherlands; (A.B.C.S.); (I.G.J.B.); (E.M.B.); (M.L.v.d.W.); (A.I.C.)
- Department of Medical Microbiology, University Medical Center Groningen, Postbus 30001, 9700 RB Groningen, The Netherlands
| | - M.L. Van de Weijer
- Department of Medical Microbiology, University Medical Center Utrecht, Postbus 85500, 3508 GA Utrecht, The Netherlands; (A.B.C.S.); (I.G.J.B.); (E.M.B.); (M.L.v.d.W.); (A.I.C.)
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - A.I. Costa
- Department of Medical Microbiology, University Medical Center Utrecht, Postbus 85500, 3508 GA Utrecht, The Netherlands; (A.B.C.S.); (I.G.J.B.); (E.M.B.); (M.L.v.d.W.); (A.I.C.)
| | - P. Hubel
- Innate Immunity Laboratory, Max-Planck Institute for Biochemistry, Am Klopferspitz 18, Martinsried, D-82152 Munich, Germany; (P.H.); (A.P.)
- Core Facility Hohenheim, Universität Hohenheim, Emil-Wolff-Straße 12, D-70599 Stuttgart, Germany
| | - A. Pichlmair
- Innate Immunity Laboratory, Max-Planck Institute for Biochemistry, Am Klopferspitz 18, Martinsried, D-82152 Munich, Germany; (P.H.); (A.P.)
- School of Medicine, Institute of Virology, Technical University of Munich, Schneckenburgerstr 8, D-81675 Munich, Germany
- German Center for Infection Research (DZIF), Munich Partner Site, D-85764 Neuherberg, Germany
| | - R.J. Lebbink
- Department of Medical Microbiology, University Medical Center Utrecht, Postbus 85500, 3508 GA Utrecht, The Netherlands; (A.B.C.S.); (I.G.J.B.); (E.M.B.); (M.L.v.d.W.); (A.I.C.)
- Correspondence: (R.J.L.); (E.J.H.J.W.); Tel.: +31-887550627 (R.J.L.); +31-887550862 (E.J.H.J.W.)
| | - E.J.H.J. Wiertz
- Department of Medical Microbiology, University Medical Center Utrecht, Postbus 85500, 3508 GA Utrecht, The Netherlands; (A.B.C.S.); (I.G.J.B.); (E.M.B.); (M.L.v.d.W.); (A.I.C.)
- Correspondence: (R.J.L.); (E.J.H.J.W.); Tel.: +31-887550627 (R.J.L.); +31-887550862 (E.J.H.J.W.)
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28
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Salio M, Awad W, Veerapen N, Gonzalez-Lopez C, Kulicke C, Waithe D, Martens AWJ, Lewinsohn DM, Hobrath JV, Cox LR, Rossjohn J, Besra GS, Cerundolo V. Ligand-dependent downregulation of MR1 cell surface expression. Proc Natl Acad Sci U S A 2020; 117:10465-10475. [PMID: 32341160 PMCID: PMC7229755 DOI: 10.1073/pnas.2003136117] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The antigen-presenting molecule MR1 presents riboflavin-based metabolites to Mucosal-Associated Invariant T (MAIT) cells. While MR1 egress to the cell surface is ligand-dependent, the ability of small-molecule ligands to impact on MR1 cellular trafficking remains unknown. Arising from an in silico screen of the MR1 ligand-binding pocket, we identify one ligand, 3-([2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-yl]formamido)propanoic acid, DB28, as well as an analog, methyl 3-([2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-yl]formamido)propanoate, NV18.1, that down-regulate MR1 from the cell surface and retain MR1 molecules in the endoplasmic reticulum (ER) in an immature form. DB28 and NV18.1 compete with the known MR1 ligands, 5-OP-RU and acetyl-6-FP, for MR1 binding and inhibit MR1-dependent MAIT cell activation. Crystal structures of the MAIT T cell receptor (TCR) complexed with MR1-DB28 and MR1-NV18.1, show that these two ligands reside within the A'-pocket of MR1. Neither ligand forms a Schiff base with MR1 molecules; both are nevertheless sequestered by a network of hydrophobic and polar contacts. Accordingly, we define a class of compounds that inhibits MR1 cellular trafficking.
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Affiliation(s)
- Mariolina Salio
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom;
| | - Wael Awad
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Natacha Veerapen
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston B15 2TT, Birmingham, United Kingdom
| | - Claudia Gonzalez-Lopez
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Corinna Kulicke
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, OR 97239
- Research Department, Portland Veterans Administration Healthcare System, Portland, OR 97239
| | - Dominic Waithe
- MRC Centre for Computational Biology, The Wolfson Imaging Centre, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Anne W J Martens
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - David M Lewinsohn
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, OR 97239
- Research Department, Portland Veterans Administration Healthcare System, Portland, OR 97239
| | - Judith V Hobrath
- Drug Discovery Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Liam R Cox
- School of Chemistry, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Jamie Rossjohn
- Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
- Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, VIC 3800, Australia
- Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Gurdyal S Besra
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston B15 2TT, Birmingham, United Kingdom;
| | - Vincenzo Cerundolo
- MRC Human Immunology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
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29
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Trowitzsch S, Tampé R. Multifunctional Chaperone and Quality Control Complexes in Adaptive Immunity. Annu Rev Biophys 2020; 49:135-161. [PMID: 32004089 DOI: 10.1146/annurev-biophys-121219-081643] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The fundamental process of adaptive immunity relies on the differentiation of self from nonself. Nucleated cells are continuously monitored by effector cells of the immune system, which police the peptide status presented via cell surface molecules. Recent integrative structural approaches have provided insights toward our understanding of how sophisticated cellular machineries shape such hierarchical immune surveillance. Biophysical and structural achievements were invaluable for defining the interconnection of many key factors during antigen processing and presentation, and helped to solve several conundrums that persisted for many years. In this review, we illuminate the numerous quality control machineries involved in different steps during the maturation of major histocompatibility complex class I (MHC I) proteins, from their synthesis in the endoplasmic reticulum to folding and trafficking via the secretory pathway, optimization of antigenic cargo, final release to the cell surface, and engagement with their cognate receptors on cytotoxic T lymphocytes.
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Affiliation(s)
- Simon Trowitzsch
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany; ,
| | - Robert Tampé
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany; ,
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30
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Tao S, Tao R, Busch DH, Widera M, Schaal H, Drexler I. Sequestration of Late Antigens Within Viral Factories Impairs MVA Vector-Induced Protective Memory CTL Responses. Front Immunol 2019; 10:2850. [PMID: 31867011 PMCID: PMC6904312 DOI: 10.3389/fimmu.2019.02850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 11/20/2019] [Indexed: 01/22/2023] Open
Abstract
Cytotoxic CD8+ T cell (CTL) responses play an essential role in antiviral immunity. Here, we focused on the activation of CTL which recognize epitopes derived from viral or recombinant antigens with either early or late expression kinetics after infection with Modified Vaccinia Virus Ankara (MVA). Late antigens but not early antigens failed to efficiently stimulate murine CTL lines in vitro and were unable to activate and expand protective memory T cell responses in mice in vivo. The reduced or absent presentation of late antigens was not due to impaired antigen presentation or delayed protein synthesis, but was caused by sequestration of late antigens within viral factories (VFs). Additionally, the trapping of late antigens in VFs conflicts with antigen processing and presentation as proteasomal activity was strongly reduced or absent in VFs, suggesting inefficient antigen degradation. This study gives for the first time a mechanistic explanation for the weak immunogenicity of late viral antigens for memory CTL activation. Since MVA is preferentially used as a boost vector in heterologous prime/boost vaccinations, this is an important information for future vaccine design.
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Affiliation(s)
- Sha Tao
- Institute for Virology, Düsseldorf University Hospital, Heinrich-Heine-University, Düsseldorf, Germany
| | - Ronny Tao
- Institute for Virology, Düsseldorf University Hospital, Heinrich-Heine-University, Düsseldorf, Germany
| | - Dirk H Busch
- Institute of Microbiology, Immunology and Hygiene, Technical University Munich, Munich, Germany
| | - Marek Widera
- Institute for Virology, Düsseldorf University Hospital, Heinrich-Heine-University, Düsseldorf, Germany
| | - Heiner Schaal
- Institute for Virology, Düsseldorf University Hospital, Heinrich-Heine-University, Düsseldorf, Germany
| | - Ingo Drexler
- Institute for Virology, Düsseldorf University Hospital, Heinrich-Heine-University, Düsseldorf, Germany
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31
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Della Chiesa M, De Maria A, Muccio L, Bozzano F, Sivori S, Moretta L. Human NK Cells and Herpesviruses: Mechanisms of Recognition, Response and Adaptation. Front Microbiol 2019; 10:2297. [PMID: 31636622 PMCID: PMC6788305 DOI: 10.3389/fmicb.2019.02297] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 09/20/2019] [Indexed: 12/01/2022] Open
Abstract
NK cells contribute to early defenses against viruses through their inborn abilities that include sensing of PAMPs and inflammatory signals such as cytokines or chemokines, recognition, and killing of infected cells through activating surface receptors engagement. Moreover, they support adaptive responses via Ab-dependent mechanisms, triggered by CD16, and DC editing. Their fundamental role in anti-viral responses has been unveiled in patients with NK cell deficiencies suffering from severe Herpesvirus infections. Notably, these infections, often occurring as primary infections early in life, can be efficiently cleared by NK, T, and B cells in healthy hosts. Herpesviruses however, generate a complicated balance with the host immune system through their latency cycle moving between immune control and viral reactivation. This lifelong challenge has contributed to the development of numerous evasion mechanisms by Herpesviruses, many of which devoted to elude NK cell surveillance from viral reactivations rather than primary infections. This delicate equilibrium can be altered in proportions of healthy individuals promoting virus reactivation and, more often, in immunocompromised subjects. However, the constant stimulus provided by virus-host interplay has also favored NK-cell adaptation to Herpesviruses. During anti-HCMV responses, NK cells can reshape their receptor repertoire and function, through epigenetic remodeling, and acquire adaptive traits such as longevity and clonal expansion abilities. The major mechanisms of recognition and effector responses employed by NK cells against Herpesviruses, related to their genomic organization will be addressed, including those allowing NK cells to generate memory-like responses. In addition, the mechanisms underlying virus reactivation or control will be discussed.
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Affiliation(s)
- Mariella Della Chiesa
- Department of Experimental Medicine (DIMES), School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy.,Centre of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - Andrea De Maria
- Centre of Excellence for Biomedical Research, University of Genoa, Genoa, Italy.,Department of Health Sciences (DISSAL), School of Medical and Pharmaceutical Sciences University of Genoa, Genoa, Italy.,Clinica Malattie Infettive, Ospedale Policlinico San Martino IRCCS, Genoa, Italy
| | - Letizia Muccio
- Department of Experimental Medicine (DIMES), School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Federica Bozzano
- Laboratory of Tumor Immunology, Department of Immunology, IRCCS Ospedale Bambino Gesù, Rome, Italy
| | - Simona Sivori
- Department of Experimental Medicine (DIMES), School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy.,Centre of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - Lorenzo Moretta
- Laboratory of Tumor Immunology, Department of Immunology, IRCCS Ospedale Bambino Gesù, Rome, Italy
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32
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D’Alicandro V, Romania P, Melaiu O, Fruci D. Role of genetic variations on MHC class I antigen-processing genes in human cancer and viral-mediated diseases. Mol Immunol 2019; 113:11-15. [DOI: 10.1016/j.molimm.2018.03.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/11/2018] [Accepted: 03/29/2018] [Indexed: 01/09/2023]
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33
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Praest P, Liaci AM, Förster F, Wiertz EJ. New insights into the structure of the MHC class I peptide-loading complex and mechanisms of TAP inhibition by viral immune evasion proteins. Mol Immunol 2019; 113:103-114. [DOI: 10.1016/j.molimm.2018.03.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 03/16/2018] [Accepted: 03/22/2018] [Indexed: 01/08/2023]
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34
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Garrido G, Schrand B, Rabasa A, Levay A, D'Eramo F, Berezhnoy A, Modi S, Gefen T, Marijt K, Doorduijn E, Dudeja V, van Hall T, Gilboa E. Tumor-targeted silencing of the peptide transporter TAP induces potent antitumor immunity. Nat Commun 2019; 10:3773. [PMID: 31434881 PMCID: PMC6704146 DOI: 10.1038/s41467-019-11728-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Accepted: 08/01/2019] [Indexed: 12/21/2022] Open
Abstract
Neoantigen burden is a major determinant of tumor immunogenicity, underscored by recent clinical experience with checkpoint blockade therapy. Yet the majority of patients do not express, or express too few, neoantigens, and hence are less responsive to immune therapy. Here we describe an approach whereby a common set of new antigens are induced in tumor cells in situ by transient downregulation of the transporter associated with antigen processing (TAP). Administration of TAP siRNA conjugated to a broad-range tumor-targeting nucleolin aptamer inhibited tumor growth in multiple tumor models without measurable toxicity, was comparatively effective to vaccination against prototypic mutation-generated neoantigens, potentiated the antitumor effect of PD-1 antibody or Flt3 ligand, and induced the presentation of a TAP-independent peptide in human tumor cells. Treatment with the chemically-synthesized nucleolin aptamer-TAP siRNA conjugate represents a broadly-applicable approach to increase the antigenicity of tumor lesions and thereby enhance the effectiveness of immune potentiating therapies.
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Affiliation(s)
- Greta Garrido
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Brett Schrand
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Ailem Rabasa
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Agata Levay
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Francesca D'Eramo
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Alexey Berezhnoy
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Shrey Modi
- Department of Surgery, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Tal Gefen
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Koen Marijt
- Department of Medical Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Elien Doorduijn
- Department of Medical Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Vikas Dudeja
- Department of Surgery, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Thorbald van Hall
- Department of Medical Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Eli Gilboa
- Department of Microbiology and Immunology, University of Miami, Miller School of Medicine, Miami, FL, USA.
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35
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Gimeno IM, Cortes AL, Reddy SM, López de Juan Abad B, Käser T, Limsatanun A. Highly virulent Marek's disease virus strains affect T lymphocyte function and viability of splenocytes in commercial meat-type chickens. Avian Pathol 2019; 48:564-572. [PMID: 31294636 DOI: 10.1080/03079457.2019.1643451] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In previous studies, we have demonstrated that very virulent plus Marek's disease viruses (vv+MDV) are highly immunosuppressive in commercial meat-type chickens. The specific objectives of this work were to evaluate if vv+MDV immunosuppression (MDV-IS) is induced by reduction of lymphocyte responsiveness and/or viability. Three experiments were conducted to (i) compare vv+MDV 686 with a partially attenuated 686-BAC; (ii) compare vv+MDV strains (648A and 686) with vMDV (GA) and vvMDV (Md5); and (iii) compare chickens vaccinated with Md5-BACΔMEQ and with CVI988 + HVT. In each experiment, spleens were collected at 28-30 days post infection and lymphocytes were isolated and investigated in three ways: their proliferative response to Concanavalin A (ConA) was analysed by MTT proliferation assay; cell death, and expression of CD45 and MHC-I was studied by flow cytometry; and MHC-IA and β-2 microglobulin (B2M) expression was evaluated by real time RT-PCR. Splenocytes of chickens inoculated with vv+MDV were severely impaired to proliferate when exposed to ConA. Furthermore, vv+MDV induced severe splenocyte death that did not occur after infection with v or vvMDV strains. Vaccination with CVI988 + HVT, and at less level with Md5-BACΔMEQ reduced these negative effects. This is in contrast to our previous results in which Md5-BACΔMEQ but not CVI988 + HVT protected against MDV-IS suggesting that although cell death and decrease lymphocyte function seem to be related to MDV virulence and certainly will be associated with immunosuppression, they might not fully explain the previously reported MDV-IS. RESEARCH HIGHLIGHTS vv+MDV induces extensive death in splenocytes in meat-type chickens 28-30 dpi. vv+MDV impairs lymphocyte function in meat-type chickens 28-30 dpi. Vaccination protects against splenocyte death and reduced lymphocyte function. Cell lysis and reduced lymphocyte function do not fully explain MDV-IS.
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Affiliation(s)
- I M Gimeno
- Department of Population Health and Pathobiology, Veterinary School, North Carolina State University , Raleigh , NC , USA
| | - A L Cortes
- Department of Population Health and Pathobiology, Veterinary School, North Carolina State University , Raleigh , NC , USA
| | - S M Reddy
- College of Veterinary Medicine & Biomedical Sciences, Texas A&M University , College Station , TX , USA
| | - B López de Juan Abad
- Department of Population Health and Pathobiology, Veterinary School, North Carolina State University , Raleigh , NC , USA
| | - T Käser
- Department of Population Health and Pathobiology, Veterinary School, North Carolina State University , Raleigh , NC , USA
| | - A Limsatanun
- Department of Population Health and Pathobiology, Veterinary School, North Carolina State University , Raleigh , NC , USA.,Faculty of Veterinary Science, Prince of Songkla University , Hat Yai, Kho Hong, Songhkla , Thailand
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Schönrich G, Raftery MJ. The PD-1/PD-L1 Axis and Virus Infections: A Delicate Balance. Front Cell Infect Microbiol 2019; 9:207. [PMID: 31263684 PMCID: PMC6584848 DOI: 10.3389/fcimb.2019.00207] [Citation(s) in RCA: 181] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 05/27/2019] [Indexed: 12/17/2022] Open
Abstract
Programmed cell death protein (PD-1) and its ligands play a fundamental role in the evasion of tumor cells from antitumor immunity. Less well appreciated is the fact that the PD-1/PD-L1 axis also regulates antiviral immune responses and is therefore modulated by a number of viruses. Upregulation of PD-1 and its ligands PD-L1 and PD-L2 is observed during acute virus infection and after infection with persistent viruses including important human pathogens such as human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV). Experimental evidence suggests that insufficient signaling through the PD-1 pathway promotes immunopathology during acute infection by exaggerating primary T cell responses. If chronic infection is established, however, high levels of PD-1 expression can have unfavorable immunological consequences. Exhaustion and suppression of antiviral immune responses can result in viral immune evasion. The role of the PD-1/PD-L1 axis during viral infections is further complicated by evidence that PD-L1 also mediates inflammatory effects in the acute phase of an immune response. In this review, we discuss the intricate interplay between viruses and the PD-1/PD-L1 axis.
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Affiliation(s)
- Günther Schönrich
- Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Virology, Berlin, Germany
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The inhibitory receptors on NK cells and CTLs are upregulated in adult and adolescent patients with secondary hemophagocytic lymphohistiocytosis. Clin Immunol 2019; 202:18-28. [PMID: 30914280 DOI: 10.1016/j.clim.2019.03.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 02/15/2019] [Accepted: 03/22/2019] [Indexed: 01/18/2023]
Abstract
Hemophagocytic lymphohistiocytosis (HLH) includes primary HLH (pHLH) and secondary HLH (sHLH). Mutations that cause abnormal functions in natural killer (NK) cells and cytotoxic T lymphocytes (CTLs) are frequently identified in pHLH. However, why NK cells and CTLs exhibit abnormal functions in sHLH remains unclear. Here, we demonstrated that NK cells in sHLH exhibited a high expression of inhibitory receptor NKG2A and a low expression of activating receptor NKG2D. Besides, the expression of HLA-E on lymphocyte, the adaptor of NKG2A on NK cells, was elevated in sHLH. Moreover, CTLs in sHLH patients expressed a higher level of functional exhaustion markers PD-1, TIM-3 and LAG-3 as well as a lower secretion of IFN-γ and CD107a upon stimulation. In addition, the expression of MHC-I on lymphocytes was decreased. Taken together, our study indicates a potentially pathological mechanism of sHLH and may open up new avenues for the development of immunotherapies against sHLH.
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Expression of the Pseudorabies Virus gB Glycoprotein Triggers NK Cell Cytotoxicity and Increases Binding of the Activating NK Cell Receptor PILRβ. J Virol 2019; 93:JVI.02107-18. [PMID: 30700600 DOI: 10.1128/jvi.02107-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 01/17/2019] [Indexed: 12/21/2022] Open
Abstract
Natural killer (NK) cells are components of the innate immunity and are key players in the defense against virus-infected and malignant cells. NK cells are particularly important in the innate defense against herpesviruses, including alphaherpesviruses. Aggravated and life-threatening alphaherpesvirus-induced disease has been reported in patients with NK cell deficiencies. NK cells are regulated by a diversity of activating and inhibitory cell surface receptors that recognize specific ligands on the plasma membrane of virus-infected or malignant target cells. Although alphaherpesviruses have developed several evasion strategies against NK cell-mediated attack, alphaherpesvirus-infected cells are still readily recognized and killed by NK cells. However, the (viral) factors that trigger NK cell activation against alphaherpesvirus-infected cells are largely unknown. In this study, we show that expression of the gB glycoprotein of the alphaherpesvirus pseudorabies virus (PRV) triggers NK cell-mediated cytotoxicity, both in PRV-infected and in gB-transfected cells. In addition, we report that, like their human and murine counterpart, porcine NK cells express the activating receptor paired immunoglobulin-like type 2 receptor beta (PILRβ), and we show that gB expression triggers increased binding of recombinant porcine PILRβ to the surfaces of PRV-infected cells and gB-transfected cells.IMPORTANCE Natural killer (NK) cells display a prominent cytolytic activity against virus-infected cells and are indispensable in the innate antiviral response, particularly against herpesviruses. Despite their importance in the control of alphaherpesvirus infections, relatively little is known about the mechanisms that trigger NK cell cytotoxicity against alphaherpesvirus-infected cells. Here, using the porcine alphaherpesvirus pseudorabies virus (PRV), we found that the conserved alphaherpesvirus glycoprotein gB triggers NK cell-mediated cytotoxicity, both in virus-infected and in gB-transfected cells. In addition, we report that gB expression results in increased cell surface binding of porcine paired immunoglobulin-like type 2 receptor beta (PILRβ), an activating NK cell receptor. The interaction between PILRβ and viral gB may have consequences that stretch beyond the interaction with NK cells, including virus entry into host cells. The identification of gB as an NK cell-activating viral protein may be of importance in the construction of future vaccines and therapeutics requiring optimized interactions of alphaherpesviruses with NK cells.
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The Obligate Intracellular Bacterium Orientia tsutsugamushi Targets NLRC5 To Modulate the Major Histocompatibility Complex Class I Pathway. Infect Immun 2019; 87:IAI.00876-18. [PMID: 30559222 DOI: 10.1128/iai.00876-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 12/11/2018] [Indexed: 02/06/2023] Open
Abstract
Orientia tsutsugamushi is an obligate intracellular bacterium that infects mononuclear and endothelial cells to cause the emerging global health threat scrub typhus. The ability of O. tsutsugamushi to survive in monocytes facilitates bacterial dissemination to endothelial cells, which can subsequently lead to several potentially fatal sequelae. As a strict intracellular pathogen that lives in the cytoplasm of host cells, O. tsutsugamushi has evolved to counter adaptive immunity. How the pathogen does so and the outcome of this strategy in monocytes versus endothelial cells are poorly understood. This report demonstrates that O. tsutsugamushi reduces cellular levels of NOD-, LRR-, and CARD-containing 5 (NLRC5), a recently identified specific transactivator of major histocompatibility complex class I (MHC-I) component gene expression, to inhibit MHC-I biosynthesis. Importantly, the efficacy of this approach varies with the host cell type infected. In nonprofessional antigen-presenting HeLa and primary human aortic endothelial cells, the O. tsutsugamushi-mediated reduction of NLRC5 results in lowered MHC-I component transcription and, consequently, lower total and/or surface MHC-I levels throughout 72 h of infection. However, in infected THP-1 monocytes, which are professional antigen-presenting cells, the reductions in NLRC5 and MHC-I observed during the first 24 h reverse thereafter. O. tsutsugamushi is the first example of a microbe that targets NLRC5 to modulate the MHC-I pathway. The differential ability of O. tsutsugamushi to modulate this pathway in nonprofessional versus professional antigen-presenting cells could influence morbidity and mortality from scrub typhus.
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Sorel O, Dewals BG. The Critical Role of Genome Maintenance Proteins in Immune Evasion During Gammaherpesvirus Latency. Front Microbiol 2019; 9:3315. [PMID: 30687291 PMCID: PMC6333680 DOI: 10.3389/fmicb.2018.03315] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 12/20/2018] [Indexed: 12/25/2022] Open
Abstract
Gammaherpesviruses are important pathogens that establish latent infection in their natural host for lifelong persistence. During latency, the viral genome persists in the nucleus of infected cells as a circular episomal element while the viral gene expression program is restricted to non-coding RNAs and a few latency proteins. Among these, the genome maintenance protein (GMP) is part of the small subset of genes expressed in latently infected cells. Despite sharing little peptidic sequence similarity, gammaherpesvirus GMPs have conserved functions playing essential roles in latent infection. Among these functions, GMPs have acquired an intriguing capacity to evade the cytotoxic T cell response through self-limitation of MHC class I-restricted antigen presentation, further ensuring virus persistence in the infected host. In this review, we provide an updated overview of the main functions of gammaherpesvirus GMPs during latency with an emphasis on their immune evasion properties.
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Affiliation(s)
- Océane Sorel
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine-FARAH, University of Liège, Liège, Belgium.,Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
| | - Benjamin G Dewals
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine-FARAH, University of Liège, Liège, Belgium
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Praest P, de Buhr H, Wiertz EJHJ. A Flow Cytometry-Based Approach to Unravel Viral Interference with the MHC Class I Antigen Processing and Presentation Pathway. Methods Mol Biol 2019; 1988:187-198. [PMID: 31147941 DOI: 10.1007/978-1-4939-9450-2_14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
MHC class I molecules are an important component of the cell-mediated immune defense, presenting peptides to surveilling CD8+ cytotoxic T cells. During viral infection, MHC class I molecules carry and display viral peptides at the cell surface. CD8+ T cells that recognize these peptides will eliminate the virus-infected cells. Viruses counteract this highly sophisticated host detection system by downregulating cell surface expression of MHC class I molecules.In this chapter, we describe a flow cytometry-based method that can be used for the identification of viral gene products potentially responsible for evasion from MHC class I-restricted antigen presentation. The gene(s) of interest are expressed constitutively through lentiviral transduction of cells. Subsequently, MHC I surface expression is monitored using MHC class I-specific antibodies. Once the viral gene product responsible for MHC I downregulation has been identified, the same cells can be used to elucidate the mechanism of action. The stage at which interference with antigen processing occurs can be identified using specific assays. An essential step frequently targeted by viruses is the translocation of peptides into the ER by the transporter associated with antigen processing, TAP. TAP function can be measured using a highly specific in vitro assay involving flow cytometric evaluation of the import of a fluorescent peptide substrate.The protocol described in this chapter enables the identification of virus-encoded MHC class I inhibitors that hinder antigen processing and presentation. Subsequently, their mechanism of action can be unraveled; this knowledge may help to rectify their actions.
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Affiliation(s)
- Patrique Praest
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Hendrik de Buhr
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Emmanuel J H J Wiertz
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands.
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42
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Kundert P, Shaulsky G. Cellular allorecognition and its roles in Dictyostelium development and social evolution. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2019; 63:383-393. [PMID: 31840777 PMCID: PMC6919275 DOI: 10.1387/ijdb.190239gs] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The social amoeba Dictyostelium discoideum is a tractable model organism to study cellular allorecognition, which is the ability of a cell to distinguish itself and its genetically similar relatives from more distantly related organisms. Cellular allorecognition is ubiquitous across the tree of life and affects many biological processes. Depending on the biological context, these versatile systems operate both within and between individual organisms, and both promote and constrain functional heterogeneity. Some of the most notable allorecognition systems mediate neural self-avoidance in flies and adaptive immunity in vertebrates. D. discoideum's allorecognition system shares several structures and functions with other allorecognition systems. Structurally, its key regulators reside at a single genomic locus that encodes two highly polymorphic proteins, a transmembrane ligand called TgrC1 and its receptor TgrB1. These proteins exhibit isoform-specific, heterophilic binding across cells. Functionally, this interaction determines the extent to which co-developing D. discoideum strains co-aggregate or segregate during the aggregation phase of multicellular development. The allorecognition system thus affects both development and social evolution, as available evidence suggests that the threat of developmental cheating represents a primary selective force acting on it. Other significant characteristics that may inform the study of allorecognition in general include that D. discoideum's allorecognition system is a continuous and inclusive trait, it is pleiotropic, and it is temporally regulated.
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Affiliation(s)
- Peter Kundert
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
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Abstract
Since the publication of the DRiP (defective ribosomal product) hypothesis in 1996, numerous studies have addressed the contribution of DRiPs to generating viral antigenic peptides for CD8+ T cell immunosurveillance. Here, we review studies characterizing the generation of antigenic peptides from influenza A virus encoded DRiPs, discuss the many remaining mysteries regarding the nature of their co-translational generation, and speculate on where the future might lead.
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44
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Trowitzsch S, Tampé R. ABC Transporters in Dynamic Macromolecular Assemblies. J Mol Biol 2018; 430:4481-4495. [DOI: 10.1016/j.jmb.2018.07.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 07/24/2018] [Accepted: 07/30/2018] [Indexed: 12/28/2022]
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45
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Bagdonaite I, Vakhrushev SY, Joshi HJ, Wandall HH. Viral glycoproteomes: technologies for characterization and outlook for vaccine design. FEBS Lett 2018; 592:3898-3920. [PMID: 29961944 DOI: 10.1002/1873-3468.13177] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 06/13/2018] [Accepted: 06/26/2018] [Indexed: 12/27/2022]
Abstract
It has long been known that surface proteins of most enveloped viruses are covered with glycans. It has furthermore been demonstrated that glycosylation is essential for propagation and immune evasion for many viruses. The recent development of high-resolution mass spectrometry techniques has enabled identification not only of the precise structures but also the positions of such post-translational modifications on viruses, revealing substantial differences in extent of glycosylation and glycan maturation for different classes of viruses. In-depth characterization of glycosylation and other post-translational modifications of viral envelope glycoproteins is essential for rational design of vaccines and antivirals. In this Review, we provide an overview of techniques used to address viral glycosylation and summarize information on glycosylation of enveloped viruses representing ongoing public health challenges. Furthermore, we discuss how knowledge on glycosylation can be translated to means to prevent and combat viral infections.
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Affiliation(s)
- Ieva Bagdonaite
- Department of Cellular and Molecular Medicine, Copenhagen Center for Glycomics, University of Copenhagen, Denmark
| | - Sergey Y Vakhrushev
- Department of Cellular and Molecular Medicine, Copenhagen Center for Glycomics, University of Copenhagen, Denmark
| | - Hiren J Joshi
- Department of Cellular and Molecular Medicine, Copenhagen Center for Glycomics, University of Copenhagen, Denmark
| | - Hans H Wandall
- Department of Cellular and Molecular Medicine, Copenhagen Center for Glycomics, University of Copenhagen, Denmark
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Bagdonaite I, Wandall HH. Global aspects of viral glycosylation. Glycobiology 2018; 28:443-467. [PMID: 29579213 PMCID: PMC7108637 DOI: 10.1093/glycob/cwy021] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 02/10/2018] [Accepted: 03/21/2018] [Indexed: 12/15/2022] Open
Abstract
Enveloped viruses encompass some of the most common human pathogens causing infections of different severity, ranging from no or very few symptoms to lethal disease as seen with the viral hemorrhagic fevers. All enveloped viruses possess an envelope membrane derived from the host cell, modified with often heavily glycosylated virally encoded glycoproteins important for infectivity, viral particle formation and immune evasion. While N-linked glycosylation of viral envelope proteins is well characterized with respect to location, structure and site occupancy, information on mucin-type O-glycosylation of these proteins is less comprehensive. Studies on viral glycosylation are often limited to analysis of recombinant proteins that in most cases are produced in cell lines with a glycosylation capacity different from the capacity of the host cells. The glycosylation pattern of the produced recombinant glycoproteins might therefore be different from the pattern on native viral proteins. In this review, we provide a historical perspective on analysis of viral glycosylation, and summarize known roles of glycans in the biology of enveloped human viruses. In addition, we describe how to overcome the analytical limitations by using a global approach based on mass spectrometry to identify viral O-glycosylation in virus-infected cell lysates using the complex enveloped virus herpes simplex virus type 1 as a model. We underscore that glycans often pay important contributions to overall protein structure, function and immune recognition, and that glycans represent a crucial determinant for vaccine design. High throughput analysis of glycosylation on relevant glycoprotein formulations, as well as data compilation and sharing is therefore important to identify consensus glycosylation patterns for translational applications.
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Affiliation(s)
- Ieva Bagdonaite
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, Copenhagen N, Denmark
| | - Hans H Wandall
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, Copenhagen N, Denmark
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Abstract
Natural killer (NK) cells play an important role in the host response against viral infections and cancer development. They are able to kill virus-infected and tumor cells, and they produce different important cytokines that stimulate the antiviral and antitumor adaptive immune response, particularly interferon gamma. NK cells are of particular importance in herpesvirus infections, which is illustrated by systemic and life-threatening herpesvirus disease symptoms in patients with deficiencies in NK cell activity and by the myriad of reports describing herpesvirus NK cell evasion strategies. The latter is particularly obvious for cytomegaloviruses, but increasing evidence indicates that most, if not all, members of the herpesvirus family suppress NK cell activity to some extent. This review discusses the different NK cell evasion strategies described for herpesviruses and how this knowledge may translate to clinical applications.
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Gavvovidis I, Leisegang M, Willimsky G, Miller N, Nghiem P, Blankenstein T. Targeting Merkel Cell Carcinoma by Engineered T Cells Specific to T-Antigens of Merkel Cell Polyomavirus. Clin Cancer Res 2018; 24:3644-3655. [PMID: 29669806 DOI: 10.1158/1078-0432.ccr-17-2661] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 02/28/2018] [Accepted: 04/13/2018] [Indexed: 12/20/2022]
Abstract
Purpose: The causative agent of most cases of Merkel cell carcinoma (MCC) has been identified as the Merkel cell polyomavirus (MCV). MCV-encoded T antigens (Tag) are essential not only for virus-mediated tumorigenesis but also for maintaining MCC cell lines in vitro MCV Tags are thus an appealing target for viral oncoprotein-directed T-cell therapy for MCC. With this study, we aimed to isolate and characterize Tag-specific T-cell receptors (TCR) for potential use in gene therapy clinical trials.Experimental Design: T-cell responses against MCV Tag epitopes were investigated by immunizing transgenic mice that express a diverse human TCR repertoire restricted to HLA-A2. Human lymphocytes genetically engineered to express Tag-specific TCRs were tested for specific reactivity against MCC cell lines. The therapeutic potential of Tag-specific TCR gene therapy was tested in a syngeneic cancer model.Results: We identified naturally processed epitopes of MCV Tags and isolated Tag-specific TCRs. T cells expressing these TCRs were activated by HLA-A2-positive cells loaded with cognate peptide or cells that stably expressed MCV Tags. We showed cytotoxic potential of T cells engineered to express these TCRs in vitro and demonstrated regression of established tumors in a mouse model upon TCR gene therapy.Conclusions: Our findings demonstrate that MCC cells can be targeted by MCV Tag-specific TCRs. Although recent findings suggest that approximately half of MCC patients benefit from PD-1 pathway blockade, additional patients may benefit if their endogenous T-cell response can be augmented by infusion of transgenic MCV-specific T cells such as those described here. Clin Cancer Res; 24(15); 3644-55. ©2018 AACR.
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Affiliation(s)
- Ioannis Gavvovidis
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,Institute of Immunology, Charité, Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Matthias Leisegang
- Institute of Immunology, Charité, Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany
| | - Gerald Willimsky
- Institute of Immunology, Charité, Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,German Cancer Research Center, Heidelberg, Germany
| | - Natalie Miller
- University of Washington, Dermatology/Medicine/Pathology, Seattle, Washington
| | - Paul Nghiem
- University of Washington, Dermatology/Medicine/Pathology, Seattle, Washington
| | - Thomas Blankenstein
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. .,Institute of Immunology, Charité, Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany
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EBNA1: Oncogenic Activity, Immune Evasion and Biochemical Functions Provide Targets for Novel Therapeutic Strategies against Epstein-Barr Virus- Associated Cancers. Cancers (Basel) 2018; 10:cancers10040109. [PMID: 29642420 PMCID: PMC5923364 DOI: 10.3390/cancers10040109] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 03/26/2018] [Accepted: 03/29/2018] [Indexed: 12/12/2022] Open
Abstract
The presence of the Epstein-Barr virus (EBV)-encoded nuclear antigen-1 (EBNA1) protein in all EBV-carrying tumours constitutes a marker that distinguishes the virus-associated cancer cells from normal cells and thereby offers opportunities for targeted therapeutic intervention. EBNA1 is essential for viral genome maintenance and also for controlling viral gene expression and without EBNA1, the virus cannot persist. EBNA1 itself has been linked to cell transformation but the underlying mechanism of its oncogenic activity has been unclear. However, recent data are starting to shed light on its growth-promoting pathways, suggesting that targeting EBNA1 can have a direct growth suppressing effect. In order to carry out its tasks, EBNA1 interacts with cellular factors and these interactions are potential therapeutic targets, where the aim would be to cripple the virus and thereby rid the tumour cells of any oncogenic activity related to the virus. Another strategy to target EBNA1 is to interfere with its expression. Controlling the rate of EBNA1 synthesis is critical for the virus to maintain a sufficient level to support viral functions, while at the same time, restricting expression is equally important to prevent the immune system from detecting and destroying EBNA1-positive cells. To achieve this balance EBNA1 has evolved a unique repeat sequence of glycines and alanines that controls its own rate of mRNA translation. As the underlying molecular mechanisms for how this repeat suppresses its own rate of synthesis in cis are starting to be better understood, new therapeutic strategies are emerging that aim to modulate the translation of the EBNA1 mRNA. If translation is induced, it could increase the amount of EBNA1-derived antigenic peptides that are presented to the major histocompatibility (MHC) class I pathway and thus, make EBV-carrying cancers better targets for the immune system. If translation is further suppressed, this would provide another means to cripple the virus.
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A large-scale immunoinformatics analysis of the human papillomaviruses reveals a common E5 oncoprotein-pattern to evade the immune response. GENE REPORTS 2018. [DOI: 10.1016/j.genrep.2017.10.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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