1
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Zhao GX, Fang XY, Bu GL, Chen SJB, Sun C, Li T, Xie C, Wang Y, Li SX, Meng N, Feng GK, Zhong Q, Kong XW, Liu Z, Zeng MS. Potent human monoclonal antibodies targeting Epstein-Barr virus gp42 reveal vulnerable sites for virus infection. Cell Rep Med 2024; 5:101573. [PMID: 38776874 PMCID: PMC11148859 DOI: 10.1016/j.xcrm.2024.101573] [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: 10/18/2023] [Revised: 01/10/2024] [Accepted: 04/23/2024] [Indexed: 05/25/2024]
Abstract
Epstein-Barr virus (EBV) is linked to various malignancies and autoimmune diseases, posing a significant global health challenge due to the lack of specific treatments or vaccines. Despite its crucial role in EBV infection in B cells, the mechanisms of the glycoprotein gp42 remain elusive. In this study, we construct an antibody phage library from 100 EBV-positive individuals, leading to the identification of two human monoclonal antibodies, 2B7 and 2C1. These antibodies effectively neutralize EBV infection in vitro and in vivo while preserving gp42's interaction with the human leukocyte antigen class II (HLA-II) receptor. Structural analysis unveils their distinct binding epitopes on gp42, different from the HLA-II binding site. Furthermore, both 2B7 and 2C1 demonstrate potent neutralization of EBV infection in HLA-II-positive epithelial cells, expanding our understanding of gp42's role. Overall, this study introduces two human anti-gp42 antibodies with potential implications for developing EBV vaccines targeting gp42 epitopes, addressing a critical gap in EBV research.
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Affiliation(s)
- Ge-Xin Zhao
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Xin-Yan Fang
- Cryo-electron Microscopy Center, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China; Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Guo-Long Bu
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Shuai-Jia-Bin Chen
- Cryo-electron Microscopy Center, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China; Department of Chemical Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Cong Sun
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Ting Li
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Chu Xie
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Yu Wang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Shu-Xin Li
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Ning Meng
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Guo-Kai Feng
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Qian Zhong
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China
| | - Xiang-Wei Kong
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China; Department of Otorhinolaryngology, Sun Yat-sen Memorial Hospital, Guangzhou, China.
| | - Zheng Liu
- Cryo-electron Microscopy Center, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
| | - Mu-Sheng Zeng
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou 510060, China.
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2
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Bu W, Kumar A, Board NL, Kim J, Dowdell K, Zhang S, Lei Y, Hostal A, Krogmann T, Wang Y, Pittaluga S, Marcotrigiano J, Cohen JI. Epstein-Barr virus gp42 antibodies reveal sites of vulnerability for receptor binding and fusion to B cells. Immunity 2024; 57:559-573.e6. [PMID: 38479361 PMCID: PMC11000673 DOI: 10.1016/j.immuni.2024.02.008] [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: 08/15/2023] [Revised: 12/13/2023] [Accepted: 02/08/2024] [Indexed: 04/10/2024]
Abstract
Epstein-Barr virus (EBV) causes infectious mononucleosis and is associated with B cell lymphomas. EBV glycoprotein 42 (gp42) binds HLA class II and activates membrane fusion with B cells. We isolated gp42-specific monoclonal antibodies (mAbs), A10 and 4C12, which use distinct mechanisms to neutralize virus infection. mAb A10 was more potent than the only known neutralizing gp42 mAb, F-2-1, in neutralizing EBV infection and blocking binding to HLA class II. mAb 4C12 was similar to mAb A10 in inhibiting glycoprotein-mediated B cell fusion but did not block receptor binding, and it was less effective in neutralizing infection. Crystallographic structures of gH/gL/gp42/A10 and gp42/4C12 complexes revealed two distinct sites of vulnerability on gp42 for receptor binding and B cell fusion. Passive transfer of mAb A10 into humanized mice conferred nearly 100% protection from viremia and EBV lymphomas after EBV challenge. These findings identify vulnerable sites on EBV that may facilitate therapeutics and vaccines.
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Affiliation(s)
- Wei Bu
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ashish Kumar
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nathan L Board
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - JungHyun Kim
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kennichi Dowdell
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shu Zhang
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yona Lei
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Anna Hostal
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tammy Krogmann
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yanmei Wang
- Clinical Services Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Stefania Pittaluga
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Joseph Marcotrigiano
- Structural Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Jeffrey I Cohen
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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3
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Uribe FR, González VPI, Kalergis AM, Soto JA, Bohmwald K. Understanding the Neurotrophic Virus Mechanisms and Their Potential Effect on Systemic Lupus Erythematosus Development. Brain Sci 2024; 14:59. [PMID: 38248274 PMCID: PMC10813552 DOI: 10.3390/brainsci14010059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/24/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
Central nervous system (CNS) pathologies are a public health concern, with viral infections one of their principal causes. These viruses are known as neurotropic pathogens, characterized by their ability to infiltrate the CNS and thus interact with various cell populations, inducing several diseases. The immune response elicited by neurotropic viruses in the CNS is commanded mainly by microglia, which, together with other local cells, can secrete inflammatory cytokines to fight the infection. The most relevant neurotropic viruses are adenovirus (AdV), cytomegalovirus (CMV), enterovirus (EV), Epstein-Barr Virus (EBV), herpes simplex virus type 1 (HSV-1), and herpes simplex virus type 2 (HSV-2), lymphocytic choriomeningitis virus (LCMV), and the newly discovered SARS-CoV-2. Several studies have associated a viral infection with systemic lupus erythematosus (SLE) and neuropsychiatric lupus (NPSLE) manifestations. This article will review the knowledge about viral infections, CNS pathologies, and the immune response against them. Also, it allows us to understand the relevance of the different viral proteins in developing neuronal pathologies, SLE and NPSLE.
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Affiliation(s)
- Felipe R. Uribe
- Millennium Institute on Immunology and Immunotherapy, Laboratorio de Inmunología Traslacional, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370146, Chile; (F.R.U.); (V.P.I.G.)
| | - Valentina P. I. González
- Millennium Institute on Immunology and Immunotherapy, Laboratorio de Inmunología Traslacional, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370146, Chile; (F.R.U.); (V.P.I.G.)
| | - Alexis M. Kalergis
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8330025, Chile;
- Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Jorge A. Soto
- Millennium Institute on Immunology and Immunotherapy, Laboratorio de Inmunología Traslacional, Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago 8370146, Chile; (F.R.U.); (V.P.I.G.)
| | - Karen Bohmwald
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma, Santiago 8910060, Chile
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4
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Xie M. Virus-Induced Cell Fusion and Syncytia Formation. Results Probl Cell Differ 2024; 71:283-318. [PMID: 37996683 DOI: 10.1007/978-3-031-37936-9_14] [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] [Indexed: 11/25/2023]
Abstract
Most enveloped viruses encode viral fusion proteins to penetrate host cell by membrane fusion. Interestingly, many enveloped viruses can also use viral fusion proteins to induce cell-cell fusion, both in vitro and in vivo, leading to the formation of syncytia or multinucleated giant cells (MGCs). In addition, some non-enveloped viruses encode specialized viral proteins that induce cell-cell fusion to facilitate viral spread. Overall, viruses that can induce cell-cell fusion are nearly ubiquitous in mammals. Virus cell-to-cell spread by inducing cell-cell fusion may overcome entry and post-entry blocks in target cells and allow evasion of neutralizing antibodies. However, molecular mechanisms of virus-induced cell-cell fusion remain largely unknown. Here, I summarize the current understanding of virus-induced cell fusion and syncytia formation.
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Affiliation(s)
- Maorong Xie
- Division of Infection and Immunity, UCL, London, UK.
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5
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Wu Q, Zhong L, Wei D, Zhang W, Hong J, Kang Y, Chen K, Huang Y, Zheng Q, Xu M, Zeng MS, Zeng YX, Xia N, Zhao Q, Krummenacher C, Chen Y, Zhang X. Neutralizing antibodies against EBV gp42 show potent in vivo protection and define novel epitopes. Emerg Microbes Infect 2023; 12:2245920. [PMID: 37542379 PMCID: PMC10443957 DOI: 10.1080/22221751.2023.2245920] [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: 03/29/2023] [Revised: 07/23/2023] [Accepted: 08/03/2023] [Indexed: 08/06/2023]
Abstract
Epstein-Barr virus (EBV) is the first reported human oncogenic virus and infects more than 95% of the human population worldwide. EBV latent infection in B lymphocytes is essential for viral persistence. Glycoprotein gp42 is an indispensable member of the triggering complex for EBV entry into B cells. The C-type lectin domain (CTLD) of gp42 plays a key role in receptor binding and is the major target of neutralizing antibodies. Here, we isolated two rabbit antibodies, 1A7 and 6G7, targeting gp42 CTLD with potent neutralizing activity against B cell infection. Antibody 6G7 efficiently protects humanized mice from lethal EBV challenge and EBV-induced lymphoma. Neutralizing epitopes targeted by antibodies 1A7 and 6G7 are distinct and novel. Antibody 6G7 blocks gp42 binding to B cell surface and both 1A7 and 6G7 inhibit membrane fusion with B cells. Furthermore, 1A7- and 6G7-like antibodies in immunized sera are major contributors to B cell neutralization. This study demonstrates that anti-gp42 neutralizing antibodies are effective in inhibiting EBV infection and sheds light on the design of gp42-based vaccines and therapeutics.
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Affiliation(s)
- Qian Wu
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Ling Zhong
- College of Pharmacy, Chongqing Medical University, Chongqing, People’s Republic of China
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Experimental Research, Sun Yat-sen University Cancer Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Dongmei Wei
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Wanlin Zhang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Experimental Research, Sun Yat-sen University Cancer Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Junping Hong
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Yinfeng Kang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Experimental Research, Sun Yat-sen University Cancer Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Kaiyun Chen
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Yang Huang
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Qingbing Zheng
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Miao Xu
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Experimental Research, Sun Yat-sen University Cancer Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Mu-Sheng Zeng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Experimental Research, Sun Yat-sen University Cancer Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Yi-Xin Zeng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Experimental Research, Sun Yat-sen University Cancer Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Ningshao Xia
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Qinjian Zhao
- College of Pharmacy, Chongqing Medical University, Chongqing, People’s Republic of China
| | - Claude Krummenacher
- Department of Biological and Biomedical Sciences, Rowan University, Glassboro, NJ, USA
| | - Yixin Chen
- State Key Laboratory of Vaccines for Infectious Diseases, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Collaborative Innovation Center of Biologic Products, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Life Sciences, School of Public Health, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, People’s Republic of China
| | - Xiao Zhang
- College of Pharmacy, Chongqing Medical University, Chongqing, People’s Republic of China
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6
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Ruiz-Pablos M, Paiva B, Zabaleta A. Epstein-Barr virus-acquired immunodeficiency in myalgic encephalomyelitis-Is it present in long COVID? J Transl Med 2023; 21:633. [PMID: 37718435 PMCID: PMC10506247 DOI: 10.1186/s12967-023-04515-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 09/08/2023] [Indexed: 09/19/2023] Open
Abstract
Both myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) and long COVID (LC) are characterized by similar immunological alterations, persistence of chronic viral infection, autoimmunity, chronic inflammatory state, viral reactivation, hypocortisolism, and microclot formation. They also present with similar symptoms such as asthenia, exercise intolerance, sleep disorders, cognitive dysfunction, and neurological and gastrointestinal complaints. In addition, both pathologies present Epstein-Barr virus (EBV) reactivation, indicating the possibility of this virus being the link between both pathologies. Therefore, we propose that latency and recurrent EBV reactivation could generate an acquired immunodeficiency syndrome in three steps: first, an acquired EBV immunodeficiency develops in individuals with "weak" EBV HLA-II haplotypes, which prevents the control of latency I cells. Second, ectopic lymphoid structures with EBV latency form in different tissues (including the CNS), promoting inflammatory responses and further impairment of cell-mediated immunity. Finally, immune exhaustion occurs due to chronic exposure to viral antigens, with consolidation of the disease. In the case of LC, prior to the first step, there is the possibility of previous SARS-CoV-2 infection in individuals with "weak" HLA-II haplotypes against this virus and/or EBV.
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Affiliation(s)
| | - Bruno Paiva
- Clinica Universidad de Navarra, Centro de Investigación Médica Aplicada (CIMA), IdiSNA, Instituto de Investigación Sanitaria de Navarra, Av. Pío XII 55, 31008, Pamplona, Spain
| | - Aintzane Zabaleta
- Clinica Universidad de Navarra, Centro de Investigación Médica Aplicada (CIMA), IdiSNA, Instituto de Investigación Sanitaria de Navarra, Av. Pío XII 55, 31008, Pamplona, Spain.
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7
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Gerencer M, McGuffin LJ. Are the integrin binding motifs within SARS CoV-2 spike protein and MHC class II alleles playing the key role in COVID-19? Front Immunol 2023; 14:1177691. [PMID: 37492575 PMCID: PMC10364474 DOI: 10.3389/fimmu.2023.1177691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/22/2023] [Indexed: 07/27/2023] Open
Abstract
The previous studies on the RGD motif (aa403-405) within the SARS CoV-2 spike (S) protein receptor binding domain (RBD) suggest that the RGD motif binding integrin(s) may play an important role in infection of the host cells. We also discussed the possible role of two other integrin binding motifs that are present in S protein: LDI (aa585-587) and ECD (661-663), the motifs used by some other viruses in the course of infection. The MultiFOLD models for protein structure analysis have shown that the ECD motif is clearly accessible in the S protein, whereas the RGD and LDI motifs are partially accessible. Furthermore, the amino acids that are present in Epstein-Barr virus protein (EBV) gp42 playing very important role in binding to the HLA-DRB1 molecule and in the subsequent immune response evasion, are also present in the S protein heptad repeat-2. Our MultiFOLD model analyses have shown that these amino acids are clearly accessible on the surface in each S protein chain as monomers and in the homotrimer complex and bind to HLA-DRB1 β chain. Therefore, they may have the identical role in SARS CoV-2 immune evasion as in EBV infection. The prediction analyses of the MHC class II binding peptides within the S protein have shown that the RGD motif is present in the core 9-mer peptide IRGDEVRQI within the two HLA-DRB1*03:01 and HLA-DRB3*01.01 strong binding 15-mer peptides suggesting that RGD motif may be the potential immune epitope. Accordingly, infected HLA-DRB1*03:01 or HLA-DRB3*01.01 positive individuals may develop high affinity anti-RGD motif antibodies that react with the RGD motif in the host proteins, like fibrinogen, thrombin or von Willebrand factor, affecting haemostasis or participating in autoimmune disorders.
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Affiliation(s)
| | - Liam J. McGuffin
- School of Biological Sciences, University of Reading, Reading, United Kingdom
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8
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Kremling V, Loll B, Pach S, Dahmani I, Weise C, Wolber G, Chiantia S, Wahl MC, Osterrieder N, Azab W. Crystal structures of glycoprotein D of equine alphaherpesviruses reveal potential binding sites to the entry receptor MHC-I. Front Microbiol 2023; 14:1197120. [PMID: 37250020 PMCID: PMC10213783 DOI: 10.3389/fmicb.2023.1197120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 04/18/2023] [Indexed: 05/31/2023] Open
Abstract
Cell entry of most alphaherpesviruses is mediated by the binding of glycoprotein D (gD) to different cell surface receptors. Equine herpesvirus type 1 (EHV-1) and EHV-4 gDs interact with equine major histocompatibility complex I (MHC-I) to initiate entry into equine cells. We have characterized the gD-MHC-I interaction by solving the crystal structures of EHV-1 and EHV-4 gDs (gD1, gD4), performing protein-protein docking simulations, surface plasmon resonance (SPR) analysis, and biological assays. The structures of gD1 and gD4 revealed the existence of a common V-set immunoglobulin-like (IgV-like) core comparable to those of other gD homologs. Molecular modeling yielded plausible binding hypotheses and identified key residues (F213 and D261) that are important for virus binding. Altering the key residues resulted in impaired virus growth in cells, which highlights the important role of these residues in the gD-MHC-I interaction. Taken together, our results add to our understanding of the initial herpesvirus-cell interactions and will contribute to the targeted design of antiviral drugs and vaccine development.
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Affiliation(s)
- Viviane Kremling
- Institut für Virologie, Robert von Ostertag-Haus, Zentrum für Infektionsmedizin, Freie Universität Berlin, Berlin, Germany
| | - Bernhard Loll
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Szymon Pach
- Institute of Pharmacy (Pharmaceutical Chemistry), Freie Universität Berlin, Berlin, Germany
| | - Ismail Dahmani
- Universität Potsdam, Institut für Biochemie und Biologie, Potsdam, Brandenburg, Germany
| | - Christoph Weise
- BioSupraMol Core Facility, Bio-Mass Spectrometry, Freie Universität Berlin, Berlin, Germany
| | - Gerhard Wolber
- Institute of Pharmacy (Pharmaceutical Chemistry), Freie Universität Berlin, Berlin, Germany
| | - Salvatore Chiantia
- Universität Potsdam, Institut für Biochemie und Biologie, Potsdam, Brandenburg, Germany
| | - Markus C. Wahl
- Laboratory of Structural Biochemistry, Freie Universität Berlin, Berlin, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie, Macromolecular Crystallography, Berlin, Germany
| | - Nikolaus Osterrieder
- Institut für Virologie, Robert von Ostertag-Haus, Zentrum für Infektionsmedizin, Freie Universität Berlin, Berlin, Germany
- Department of Infectious Diseases and Public Health, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Walid Azab
- Institut für Virologie, Robert von Ostertag-Haus, Zentrum für Infektionsmedizin, Freie Universität Berlin, Berlin, Germany
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9
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Ratra S, Pant B, Roy K, Manohar S, Kumar P, Singh S, Tumba K, Kumari K, Singh P. A review on synthesis of antiviral drugs, in silico studies and their toxicity. J INDIAN CHEM SOC 2023. [DOI: 10.1016/j.jics.2023.100936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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10
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How EBV Infects: The Tropism and Underlying Molecular Mechanism for Viral Infection. Viruses 2022; 14:v14112372. [PMID: 36366470 PMCID: PMC9696472 DOI: 10.3390/v14112372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 10/24/2022] [Accepted: 10/24/2022] [Indexed: 01/31/2023] Open
Abstract
The Epstein-Barr virus (EBV) is associated with a variety of human malignancies, including Burkitt's lymphoma, Hodgkin's disease, nasopharyngeal carcinoma and gastric cancers. EBV infection is crucial for the oncogenesis of its host cells. The prerequisite for the establishment of infection is the virus entry. Interactions of viral membrane glycoproteins and host membrane receptors play important roles in the process of virus entry into host cells. Current studies have shown that the main tropism for EBV are B cells and epithelial cells and that EBV is also found in the tumor cells derived from NK/T cells and leiomyosarcoma. However, the process of EBV infecting B cells and epithelial cells significantly differs, relying on heterogenous glycoprotein-receptor interactions. This review focuses on the tropism and molecular mechanism of EBV infection. We systematically summarize the key molecular events that mediate EBV cell tropism and its entry into target cells and provide a comprehensive overview.
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11
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Vaccinomics to Design a Multiepitope Vaccine against Legionella pneumophila. BIOMED RESEARCH INTERNATIONAL 2022; 2022:4975721. [PMID: 36164443 PMCID: PMC9509222 DOI: 10.1155/2022/4975721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/29/2022] [Accepted: 08/16/2022] [Indexed: 11/18/2022]
Abstract
Legionella pneumophila is found in the natural aquatic environment and can resist a wide range of environmental conditions. There are around fifty species of Legionella, at least twenty-four of which are directly linked to infections in humans. L. pneumophila is the cause of Legionnaires' disease, a potentially lethal form of pneumonia. By blocking phagosome-lysosome fusion, L. pneumophila lives and proliferates inside macrophages. For this disease, there is presently no authorized multiepitope vaccine available. For the multi-epitope-based vaccine (MEBV), the best antigenic candidates were identified using immunoinformatics and subtractive proteomic techniques. Several immunoinformatics methods were utilized to predict B and T cell epitopes from vaccine candidate proteins. To construct an in silico vaccine, epitopes (07 CTL, 03 HTL, and 07 LBL) were carefully selected and docked with MHC molecules (MHC-I and MHC-II) and human TLR4 molecules. To increase the immunological response, the vaccine was combined with a 50S ribosomal adjuvant. To maximize vaccine protein expression, MEBV was cloned and reverse-translated in Escherichia coli. To prove the MEBV's efficacy, more experimental validation is required. After its development, the resulting vaccine is greatly hoped to aid in the prevention of L. pneumophila infections.
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12
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Abstract
Herpesviruses—ubiquitous pathogens that cause persistent infections—have some of the most complex cell entry mechanisms. Entry of the prototypical herpes simplex virus 1 (HSV-1) requires coordinated efforts of 4 glycoproteins, gB, gD, gH, and gL. The current model posits that the glycoproteins do not interact before receptor engagement and that binding of gD to its receptor causes a “cascade” of sequential pairwise interactions, first activating the gH/gL complex and subsequently activating gB, the viral fusogen. But how these glycoproteins interact remains unresolved. Here, using a quantitative split-luciferase approach, we show that pairwise HSV-1 glycoprotein complexes form before fusion, interact at a steady level throughout fusion, and do not depend on the presence of the cellular receptor. Based on our findings, we propose a revised “conformational cascade” model of HSV-1 entry. We hypothesize that all 4 glycoproteins assemble into a complex before fusion, with gH/gL positioned between gD and gB. Once gD binds to a cognate receptor, the proximity of the glycoproteins within this complex allows for efficient transmission of the activating signal from the receptor-activated gD to gH/gL to gB through sequential conformational changes, ultimately triggering the fusogenic refolding of gB. Our results also highlight previously unappreciated contributions of the transmembrane and cytoplasmic domains to glycoprotein interactions and fusion. Similar principles could be at play in other multicomponent viral entry systems, and the split-luciferase approach used here is a powerful tool for investigating protein-protein interactions in these and a variety of other systems.
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13
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CD4+ Cytotoxic T Cells Involved in the Development of EBV-Associated Diseases. Pathogens 2022; 11:pathogens11080831. [PMID: 35894054 PMCID: PMC9330826 DOI: 10.3390/pathogens11080831] [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: 06/27/2022] [Revised: 07/17/2022] [Accepted: 07/22/2022] [Indexed: 11/17/2022] Open
Abstract
Activated cytotoxic CD4 T cells (HLA-DR+) play an important role in the control of EBV infection, especially in cells with latency I (EBNA-1). One of the evasion mechanisms of these latency cells is generated by gp42, which, via peripherally binding to the β1 domain of the β chain of MHC class II (HLA-DQ, -DR, and -DP) of the infected B lymphocyte, can block/alter the HLA class II/T-cell receptor (TCR) interaction, and confer an increased level of susceptibility towards the development of EBV-associated autoimmune diseases or cancer in genetically predisposed individuals (HLA-DRB1* and DQB1* alleles). The main developments predisposing the factors of these diseases are: EBV infection; HLA class II risk alleles; sex; and tissue that is infiltrated with EBV-latent cells, forming ectopic lymphoid structures. Therefore, there is a need to identify treatments for eliminating cells with EBV latency, because the current treatments (e.g., antivirals and rituximab) are ineffective.
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14
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Wongwiwat W, Fournier B, Bassano I, Bayoumy A, Elgueta Karstegl C, Styles C, Bridges R, Lenoir C, BoutBoul D, Moshous D, Neven B, Kanda T, Morgan RG, White RE, Latour S, Farrell PJ. Epstein-Barr Virus Genome Deletions in Epstein-Barr Virus-Positive T/NK Cell Lymphoproliferative Diseases. J Virol 2022; 96:e0039422. [PMID: 35612313 PMCID: PMC9215254 DOI: 10.1128/jvi.00394-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/02/2022] [Indexed: 12/14/2022] Open
Abstract
The main target cells for Epstein-Barr virus (EBV) infection and persistence are B lymphocytes, although T and NK cells can also become infected. In this paper, we characterize the EBV present in 21 pediatric and adult patients who were treated in France for a range of diseases that involve infection of T or NK cells. Of these 21 cases, 5 pediatric patients (21%) and 11 adult patients (52%) were of Caucasian origin. In about 30% of the cases, some of the EBV genomes contain a large deletion. The deletions are different in every patient but tend to cluster near the BART region of the viral genome. Detailed investigation of a family in which several members have persistent T or NK cell infection by EBV indicates that the virus genome deletions arise or are selected independently in each individual patient. Genome sequence polymorphisms in the EBV in these T or NK cell diseases reflect the geographic origin of the patient and not a distinct type of EBV (the 21 cases studied included examples of both type 1 and type 2 EBV infection). Using virus produced from type 1 or type 2 EBV genomes cloned in bacterial artificial chromosome (BAC) vectors, we demonstrate infection of T cells in cord blood from healthy donors. Our results are consistent with transient infection of some T cells being part of normal asymptomatic infection by EBV in young children. IMPORTANCE EBV contributes to several types of human cancer. Some cancers and nonmalignant lymphoproliferative diseases involving T or NK cells contain EBV. These diseases are relatively frequent in Japan and China and have been shown sometimes to have deletions in the EBV genome in the disease cells. We identify further examples of deletions within the EBV genome associated with T or NK cell diseases, and we provide evidence that the virus genomes with these deletions are most likely selected in the individual cases, rather than being transmitted between people during infection. We demonstrate EBV infection of cord blood T cells by highly characterized, cloned EBV genomes and suggest that transient infection of T cells may be part of normal asymptomatic infection by EBV in young children.
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Affiliation(s)
- Wiyada Wongwiwat
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Benjamin Fournier
- Laboratory of Lymphocyte Activation and Susceptibility to EBV Infection, INSERM UMR1163, Institut Imagine, Paris, France
- Department of Pediatric Immunology, Hematology, and Rheumatology, Necker-Enfants-Malades Hospital, APHP, Paris, France
- Université de Paris, Paris, France
| | - Irene Bassano
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Amr Bayoumy
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Claudio Elgueta Karstegl
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Christine Styles
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Ray Bridges
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Christelle Lenoir
- Laboratory of Lymphocyte Activation and Susceptibility to EBV Infection, INSERM UMR1163, Institut Imagine, Paris, France
| | - David BoutBoul
- Université de Paris, Paris, France
- Department of Clinical Immunology, Saint-Louis Hospital, APHP, Paris, France
| | - Despina Moshous
- Department of Pediatric Immunology, Hematology, and Rheumatology, Necker-Enfants-Malades Hospital, APHP, Paris, France
- Université de Paris, Paris, France
| | - Bénédicte Neven
- Department of Pediatric Immunology, Hematology, and Rheumatology, Necker-Enfants-Malades Hospital, APHP, Paris, France
| | - Teru Kanda
- Division of Microbiology, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Rhys G. Morgan
- School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Robert E. White
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Sylvain Latour
- Laboratory of Lymphocyte Activation and Susceptibility to EBV Infection, INSERM UMR1163, Institut Imagine, Paris, France
- Université de Paris, Paris, France
| | - Paul J. Farrell
- Section of Virology, Department of Infectious Disease, Imperial College London, London, United Kingdom
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15
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Li F, Freed D, Heidecker G, Galli J, Durr E, Wang D. A novel high throughput assay to quantify Epstein-Barr virus neutralizing antibody activity against B-cell and epithelial cell infections for vaccine and therapeutic developments. Vaccine 2022; 40:3638-3646. [DOI: 10.1016/j.vaccine.2022.04.102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/14/2022] [Accepted: 04/29/2022] [Indexed: 11/16/2022]
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16
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Dohnálek J, Skálová T. C-type lectin-(like) fold - Protein-protein interaction patterns and utilization. Biotechnol Adv 2022; 58:107944. [PMID: 35301089 DOI: 10.1016/j.biotechadv.2022.107944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 03/04/2022] [Accepted: 03/07/2022] [Indexed: 11/02/2022]
Abstract
The C-type lectin-like fold (CTL fold) is a building block of many proteins, including saccharide-binding lectins, natural killer cell receptors, macrophage mannose receptor, selectins, collectins, snake venoms and others. Some are important players in innate immunity and are involved in the first-line response to virally infected cells or cancer cells, some play a role in antimicrobial defense, and some are potential targets for fight against problems connected with allergies, obesity, and autoimmunity. The structure of a CTL domain typically contains two α-helices, two small β-sheets and a long surface loop, with two or three disulfide bridges stabilizing the structure. This small domain is often involved in interactions with a target molecule, however, utilizing varied parts of the domain surface, with or without structural modifications. More than 500 three-dimensional structures of CTL fold-containing proteins are available in the Protein Data Bank, including a significant number of complexes with their key interacting partners (protein:protein complexes). The amount of available structural data enables a detailed analysis of the rules of interaction patterns utilized in activation, inhibition, attachment and other pathways or functionalities. Interpretation of known CTL receptor structures and all other CTL-containing proteins and complexes with described three-dimensional structures, complemented with sequence/structure/interaction correlation analysis offers a comprehensive view of the rules of interaction patterns of the CTL fold. The results are of value for prediction of interaction behavior of so far not understood CTL-containing proteins and development of new protein binders based on this fold, with applications in biomedicine or biotechnologies. It follows from the available structural data that almost the whole surface of the CTL fold is utilized in protein:protein interactions, with the heaviest frequency of utilization in the canonical interaction region. The individual categories of interactions differ in the interface buildup strategy. The strongest CTL binders rely on interfaces with large interaction area, presence of hydrophobic core, or high surface complementarity. The typical interaction surfaces of the fold are not conserved in amino acid sequence and can be utilized in design of new binders for biotechnological applications.
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Affiliation(s)
- Jan Dohnálek
- Institute of Biotechnology of the Czech Academy of Sciences, Biocev, Průmyslová 595, 25250 Vestec, Czech Republic.
| | - Tereza Skálová
- Institute of Biotechnology of the Czech Academy of Sciences, Biocev, Průmyslová 595, 25250 Vestec, Czech Republic
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17
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Gonzalez-Del Pino GL, Heldwein EE. Well Put Together—A Guide to Accessorizing with the Herpesvirus gH/gL Complexes. Viruses 2022; 14:v14020296. [PMID: 35215889 PMCID: PMC8874593 DOI: 10.3390/v14020296] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/20/2022] [Accepted: 01/22/2022] [Indexed: 02/06/2023] Open
Abstract
Herpesviruses are enveloped, double-stranded DNA viruses that infect a variety of hosts across the animal kingdom. Nine of these establish lifelong infections in humans, for which there are no cures and few vaccine or treatment options. Like all enveloped viruses, herpesviruses enter cells by fusing their lipid envelopes with a host cell membrane. Uniquely, herpesviruses distribute the functions of receptor engagement and membrane fusion across a diverse cast of glycoproteins. Two glycoprotein complexes are conserved throughout the three herpesvirus subfamilies: the trimeric gB that functions as a membrane fusogen and the heterodimeric gH/gL, the role of which is less clearly defined. Here, we highlight the conserved and divergent functions of gH/gL across the three subfamilies of human herpesviruses by comparing its interactions with a broad range of accessory viral proteins, host cell receptors, and neutralizing or inhibitory antibodies. We propose that the intrinsic structural plasticity of gH/gL enables it to function as a signal integration machine that can accept diverse regulatory inputs and convert them into a “trigger” signal that activates the fusogenic ability of gB.
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18
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Characterization of Host Cell Potential Proteins Interacting with OsHV-1 Membrane Proteins. Viruses 2021; 13:v13122518. [PMID: 34960787 PMCID: PMC8705437 DOI: 10.3390/v13122518] [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: 11/14/2021] [Revised: 12/09/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022] Open
Abstract
The interaction between viral membrane associate proteins and host cellular surface molecules should facilitate the attachment and entry of OsHV-1 into host cells. Thus, blocking the putative membrane proteins ORF25 and ORF72 of OsHV-1 with antibodies that have previously been reported to subdue OsHV-1 replication in host cells, especially ORF25. In this study, prey proteins in host hemocytes were screened by pull-down assay with recombinant baits ORF25 and ORF72, respectively. Gene Ontology (GO) analysis of these prey proteins revealed that most of them were mainly associated with binding, structural molecule activity and transport activity in the molecular function category. The protein–protein interaction (PPI) network of the prey proteins was constructed by STRING and clustered via K-means. For both ORF25 and ORF72, three clusters of these prey proteins were distinguished that were mainly associated with cytoskeleton assembly, energy metabolism and nucleic acid processing. ORF25 tended to function in synergy with actins, while ORF72 functioned mainly with tubulins. The above results suggest that these two putative membrane proteins, ORF25 and ORF72, might serve a role in the transport of viral particles with the aid of a cytoskeleton inside cells.
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19
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Sawada L, Vallinoto ACR, Brasil-Costa I. Regulation of the Immune Checkpoint Indoleamine 2,3-Dioxygenase Expression by Epstein-Barr Virus. Biomolecules 2021; 11:1792. [PMID: 34944437 PMCID: PMC8699098 DOI: 10.3390/biom11121792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/21/2021] [Accepted: 11/23/2021] [Indexed: 12/16/2022] Open
Abstract
Epstein-Barr virus (EBV) is an oncovirus ubiquitously distributed and associated with different types of cancer. The reason why only a group of infected people develop cancer is still unknown. EBV-associated cancers represent about 1.8% of all cancer deaths worldwide, with more than 150,000 new cases of cancer being reported annually. Since EBV-associated cancers are described as more aggressive and more resistant to the usual treatment compared to EBV-negative ones, the recent introduction of monoclonal antibodies (mAbs) targeting immune checkpoints (ICs) in the treatment of cancer patients represents a possible therapy for EBV-associated diseases. However, the current mAb therapies available still need improvement, since a group of patients do not respond well to treatment. Therefore, the main objective of this review is to summarize the progress made regarding the contribution of EBV infection to the expression of the IC indoleamine 2,3-dioxygenase (IDO) thus far. This IC has the potential to be used as a target in new immune therapies, such as mAbs. We hope that this work helps the development of future immunotherapies, improving the prognosis of EBV-associated cancer patients.
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Affiliation(s)
- Leila Sawada
- Immunology Laboratory, Virology Section, Evandro Chagas Institute, Ananindeua, Pará 67030-000, Brazil;
- Postgraduate Program in Virology (PPGV), Evandro Chagas Institute, Ananindeua, Pará 67030-000, Brazil
| | | | - Igor Brasil-Costa
- Immunology Laboratory, Virology Section, Evandro Chagas Institute, Ananindeua, Pará 67030-000, Brazil;
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20
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Antibody Generation and Immunogenicity Analysis of EBV gp42 N-Terminal Region. Viruses 2021; 13:v13122380. [PMID: 34960650 PMCID: PMC8707153 DOI: 10.3390/v13122380] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/16/2021] [Accepted: 11/26/2021] [Indexed: 01/21/2023] Open
Abstract
Epstein–Barr virus (EBV) is the first reported oncogenic virus and infects more than 90% of adults worldwide. EBV can establish a latent infection in B lymphocytes which is essential for persistence and transmission. Glycoprotein gp42 is an indispensable member of the triggering complex for EBV entry into a B cell. The N-terminal region of gp42 plays a key role in binding to gH/gL and triggering subsequent membrane fusion. However, no antibody has been reported to recognize this region and the immunogenicity of gp42 N-domain remains unknown. In the present study, we have generated a panel of nine mAbs against the gp42 N-terminal region (six mAbs to gp42-44-61aa and three mAbs to gp42-67-81aa). These mAbs show excellent binding activity and recognize different key residues locating on the gp42 N-domain. Among the nine mAbs, 4H7, 4H8 and 11G10 cross-react with rhLCV-gp42 while other mAbs specifically recognize EBV-gp42. Our newly obtained mAbs provide a useful tool for investigating the gp42 function and viral infection mechanism of γ-Herpesvirus. Furthermore, we assess the immunogenicity of the gp42 N-terminal region using the HBc149 particle as a carrier protein. The chimeric VLPs can induce high antibody titers and elicit neutralizing humoral responses to block EBV infection. More rational and effective designs are required to promote the gp42-N terminal region to become an epitope-based vaccine.
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21
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Zhu QY, Shan S, Yu J, Peng SY, Sun C, Zuo Y, Zhong LY, Yan SM, Zhang X, Yang Z, Peng YJ, Shi X, Cao SM, Wang X, Zeng MS, Zhang L. A potent and protective human neutralizing antibody targeting a novel vulnerable site of Epstein-Barr virus. Nat Commun 2021; 12:6624. [PMID: 34785638 PMCID: PMC8595662 DOI: 10.1038/s41467-021-26912-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 10/26/2021] [Indexed: 12/13/2022] Open
Abstract
Epstein-Barr virus (EBV) is associated with a range of epithelial and B cell malignancies as well as autoimmune disorders, for which there are still no specific treatments or effective vaccines. Here, we isolate EBV gH/gL-specific antibodies from an EBV-infected individual. One antibody, 1D8, efficiently neutralizes EBV infection of two major target cell types, B cells and epithelial cells. In humanized mice, 1D8 provides protection against a high-dose EBV challenge by substantially reducing viral loads and associated tumor burden. Crystal structure analysis reveals that 1D8 binds to a key vulnerable interface between the D-I/D-II domains of the viral gH/gL protein, especially the D-II of the gH, thereby interfering with the gH/gL-mediated membrane fusion and binding to target cells. Overall, we identify a potent and protective neutralizing antibody capable of reducing the EBV load. The novel vulnerable site represents an attractive target that is potentially important for antibody and vaccine intervention against EBV infection.
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Affiliation(s)
- Qian-Ying Zhu
- grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center (SYSUCC), 510060 Guangzhou, China ,grid.12981.330000 0001 2360 039XDepartment of Laboratory Medicine, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518003 PR China
| | - Sisi Shan
- grid.12527.330000 0001 0662 3178NexVac Research Center, Comprehensive AIDS Research Center, Center for Infectious Diseases Research, Beijing Advanced Innovation Center for Structural Biology, School of Medicine, Tsinghua University, 100084 Beijing, China
| | - Jinfang Yu
- grid.12527.330000 0001 0662 3178The Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Collaborative Innovation Center for Biotherapy, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | | | - Cong Sun
- grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center (SYSUCC), 510060 Guangzhou, China
| | - Yanan Zuo
- grid.12527.330000 0001 0662 3178NexVac Research Center, Comprehensive AIDS Research Center, Center for Infectious Diseases Research, Beijing Advanced Innovation Center for Structural Biology, School of Medicine, Tsinghua University, 100084 Beijing, China
| | - Lan-Yi Zhong
- grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center (SYSUCC), 510060 Guangzhou, China
| | - Shu-Mei Yan
- grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center (SYSUCC), 510060 Guangzhou, China
| | - Xiao Zhang
- grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center (SYSUCC), 510060 Guangzhou, China
| | - Ziqing Yang
- grid.12527.330000 0001 0662 3178NexVac Research Center, Comprehensive AIDS Research Center, Center for Infectious Diseases Research, Beijing Advanced Innovation Center for Structural Biology, School of Medicine, Tsinghua University, 100084 Beijing, China
| | - Yong-Jian Peng
- grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center (SYSUCC), 510060 Guangzhou, China
| | - Xuanling Shi
- grid.12527.330000 0001 0662 3178NexVac Research Center, Comprehensive AIDS Research Center, Center for Infectious Diseases Research, Beijing Advanced Innovation Center for Structural Biology, School of Medicine, Tsinghua University, 100084 Beijing, China
| | - Su-Mei Cao
- grid.488530.20000 0004 1803 6191State Key Laboratory of Oncology in South China, Department of Cancer Prevention Research, Sun Yat-sen University Cancer Center (SYSUCC), 510060 Guangzhou, China
| | - Xinquan Wang
- The Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, Collaborative Innovation Center for Biotherapy, School of Life Sciences, Tsinghua University, 100084, Beijing, China.
| | - Mu-Sheng Zeng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center (SYSUCC), 510060, Guangzhou, China.
| | - Linqi Zhang
- NexVac Research Center, Comprehensive AIDS Research Center, Center for Infectious Diseases Research, Beijing Advanced Innovation Center for Structural Biology, School of Medicine, Tsinghua University, 100084, Beijing, China. .,Institute of Biopharmaceutical and Health Engineering, Tsinghua Shenzhen International Graduate School, Tsinghua University, 518055, Shenzhen, China. .,Institute of Biomedical Health Technology and Engineering, Shenzhen Bay Laboratory, 518132, Shenzhen, China.
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22
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Ruiz-Pablos M, Paiva B, Montero-Mateo R, Garcia N, Zabaleta A. Epstein-Barr Virus and the Origin of Myalgic Encephalomyelitis or Chronic Fatigue Syndrome. Front Immunol 2021; 12:656797. [PMID: 34867935 PMCID: PMC8634673 DOI: 10.3389/fimmu.2021.656797] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 10/19/2021] [Indexed: 01/04/2023] Open
Abstract
Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) affects approximately 1% of the general population. It is a chronic, disabling, multi-system disease for which there is no effective treatment. This is probably related to the limited knowledge about its origin. Here, we summarized the current knowledge about the pathogenesis of ME/CFS and revisit the immunopathobiology of Epstein-Barr virus (EBV) infection. Given the similarities between EBV-associated autoimmune diseases and cancer in terms of poor T cell surveillance of cells with EBV latency, expanded EBV-infected cells in peripheral blood and increased antibodies against EBV, we hypothesize that there could be a common etiology generated by cells with EBV latency that escape immune surveillance. Albeit inconclusive, multiple studies in patients with ME/CFS have suggested an altered cellular immunity and augmented Th2 response that could result from mechanisms of evasion to some pathogens such as EBV, which has been identified as a risk factor in a subset of ME/CFS patients. Namely, cells with latency may evade the immune system in individuals with genetic predisposition to develop ME/CFS and in consequence, there could be poor CD4 T cell immunity to mitogens and other specific antigens, as it has been described in some individuals. Ultimately, we hypothesize that within ME/CFS there is a subgroup of patients with DRB1 and DQB1 alleles that could confer greater susceptibility to EBV, where immune evasion mechanisms generated by cells with latency induce immunodeficiency. Accordingly, we propose new endeavors to investigate if anti-EBV therapies could be effective in selected ME/CFS patients.
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Affiliation(s)
| | - Bruno Paiva
- Clinica Universidad de Navarra, Centro de Investigación Medica Aplicada (CIMA), IdiSNA, Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain
| | | | - Nicolas Garcia
- Clinica Universidad de Navarra, Centro de Investigación Medica Aplicada (CIMA), IdiSNA, Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain
| | - Aintzane Zabaleta
- Clinica Universidad de Navarra, Centro de Investigación Medica Aplicada (CIMA), IdiSNA, Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain
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23
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Integrated Core Proteomics, Subtractive Proteomics, and Immunoinformatics Investigation to Unveil a Potential Multi-Epitope Vaccine against Schistosomiasis. Vaccines (Basel) 2021; 9:vaccines9060658. [PMID: 34208663 PMCID: PMC8235758 DOI: 10.3390/vaccines9060658] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/13/2021] [Accepted: 06/15/2021] [Indexed: 12/14/2022] Open
Abstract
Schistosomiasis is a parasitic infection that causes considerable morbidity and mortality in the world. Infections of parasitic blood flukes, known as schistosomes, cause the disease. No vaccine is available yet and thus there is a need to design an effective vaccine against schistosomiasis. Schistosoma japonicum, Schistosoma mansoni, and Schistosoma haematobium are the main pathogenic species that infect humans. In this research, core proteomics was combined with a subtractive proteomics pipeline to identify suitable antigenic proteins for the construction of a multi-epitope vaccine (MEV) against human-infecting Schistosoma species. The pipeline revealed two antigenic proteins-calcium binding and mycosubtilin synthase subunit C-as promising vaccine targets. T and B cell epitopes from the targeted proteins were predicted using multiple bioinformatics and immunoinformatics databases. Seven cytotoxic T cell lymphocytes (CTL), three helper T cell lymphocytes (HTL), and four linear B cell lymphocytes (LBL) epitopes were fused with a suitable adjuvant and linkers to design a 217 amino-acid-long MEV. The vaccine was coupled with a TLR-4 agonist (RS-09; Sequence: APPHALS) adjuvant to enhance the immune responses. The designed MEV was stable, highly antigenic, and non-allergenic to human use. Molecular docking, molecular dynamics (MD) simulations, and molecular mechanics/generalized Born surface area (MMGBSA) analysis were performed to study the binding affinity and molecular interactions of the MEV with human immune receptors (TLR2 and TLR4) and MHC molecules (MHC I and MHC II). The MEV expression capability was tested in an Escherichia coli (strain-K12) plasmid vector pET-28a(+). Findings of these computer assays proved the MEV as highly promising in establishing protective immunity against the pathogens; nevertheless, additional validation by in vivo and in vitro experiments is required to discuss its real immune-protective efficacy.
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Su C, Wu L, Chai Y, Qi J, Tan S, Gao GF, Song H, Yan J. Molecular basis of EphA2 recognition by gHgL from gammaherpesviruses. Nat Commun 2020; 11:5964. [PMID: 33235207 PMCID: PMC7687889 DOI: 10.1038/s41467-020-19617-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 10/19/2020] [Indexed: 01/07/2023] Open
Abstract
The human γ-herpesviruses Kaposi sarcoma associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are associated with many human malignancies. Viral glycoprotein H (gH) and glycoprotein L (gL) are crucial for the cell tropism by binding to specific receptors. Recently, EphA2 was identified as the specific entry receptor for both KSHV and EBV. Here, we characterized the crystal structures of KSHV gHgL or EBV gHgL in complex with the ligand binding domain (LBD) of EphA2. Both KSHV and EBV gHgL bind to the channel and peripheral regions of LBD primarily using gL. Extensive interactions with more contacts contribute to the higher affinity of KSHV gHgL to LBD than that of EBV gHgL. These binding characteristics were verified using cell-based fusion assays with mutations in key EphA2 residues. Our experiments suggest that multiple animal γ-herpesviruses could use EphA2 as an entry receptor, implying a potential threat to human health.
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Affiliation(s)
- Chao Su
- grid.22935.3f0000 0004 0530 8290College of Veterinary Medicine, China Agricultural University, Beijing, 100193 China
| | - Lili Wu
- grid.9227.e0000000119573309CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yan Chai
- grid.9227.e0000000119573309CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Jianxun Qi
- grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, 100049 China ,grid.9227.e0000000119573309CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Shuguang Tan
- grid.9227.e0000000119573309CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101 China
| | - George F. Gao
- grid.22935.3f0000 0004 0530 8290College of Veterinary Medicine, China Agricultural University, Beijing, 100193 China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, 100049 China ,grid.9227.e0000000119573309CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.9227.e0000000119573309Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101 China
| | - Hao Song
- grid.9227.e0000000119573309Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101 China
| | - Jinghua Yan
- grid.9227.e0000000119573309CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, 100049 China
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25
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Abstract
Herpesviruses are ubiquitous, double-stranded DNA, enveloped viruses that establish lifelong infections and cause a range of diseases. Entry into host cells requires binding of the virus to specific receptors, followed by the coordinated action of multiple viral entry glycoproteins to trigger membrane fusion. Although the core fusion machinery is conserved for all herpesviruses, each species uses distinct receptors and receptor-binding glycoproteins. Structural studies of the prototypical herpesviruses herpes simplex virus 1 (HSV-1), HSV-2, human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) entry glycoproteins have defined the interaction sites for glycoprotein complexes and receptors, and have revealed conformational changes that occur on receptor binding. Recent crystallography and electron microscopy studies have refined our model of herpesvirus entry into cells, clarifying both the conserved features and the unique features. In this Review, we discuss recent insights into herpesvirus entry by analysing the structures of entry glycoproteins, including the diverse receptor-binding glycoproteins (HSV-1 glycoprotein D (gD), EBV glycoprotein 42 (gp42) and HCMV gH-gL-gO trimer and gH-gL-UL128-UL130-UL131A pentamer), as well gH-gL and the fusion protein gB, which are conserved in all herpesviruses.
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26
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Forsyth KS, Roy NH, Peauroi E, DeHaven BC, Wold ED, Hersperger AR, Burkhardt JK, Eisenlohr LC. Ectromelia-encoded virulence factor C15 specifically inhibits antigen presentation to CD4+ T cells post peptide loading. PLoS Pathog 2020; 16:e1008685. [PMID: 32745153 PMCID: PMC7425992 DOI: 10.1371/journal.ppat.1008685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 08/13/2020] [Accepted: 06/06/2020] [Indexed: 01/02/2023] Open
Abstract
Smallpox and monkeypox pose severe threats to human health. Other orthopoxviruses are comparably virulent in their natural hosts, including ectromelia, the cause of mousepox. Disease severity is linked to an array of immunomodulatory proteins including the B22 family, which has homologs in all pathogenic orthopoxviruses but not attenuated vaccine strains. We demonstrate that the ectromelia B22 member, C15, is necessary and sufficient for selective inhibition of CD4+ but not CD8+ T cell activation by immunogenic peptide and superantigen. Inhibition is achieved not by down-regulation of surface MHC- II or co-stimulatory protein surface expression but rather by interference with antigen presentation. The appreciable outcome is interference with CD4+ T cell synapse formation as determined by imaging studies and lipid raft disruption. Consequently, CD4+ T cell activating stimulus shifts to uninfected antigen-presenting cells that have received antigen from infected cells. This work provides insight into the immunomodulatory strategies of orthopoxviruses by elucidating a mechanism for specific targeting of CD4+ T cell activation, reflecting the importance of this cell type in control of the virus.
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Affiliation(s)
- Katherine S. Forsyth
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Nathan H. Roy
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Elise Peauroi
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Brian C. DeHaven
- Department of Biology, La Salle University, Philadelphia, Pennsylvania, United States of America
| | - Erik D. Wold
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Adam R. Hersperger
- Department of Biology, Albright College, Reading, Pennsylvania, United States of America
| | - Janis K. Burkhardt
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania, United States of America
| | - Laurence C. Eisenlohr
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania, United States of America
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27
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Liu W, Cui Y, Wang C, Li Z, Gong D, Dai X, Bi GQ, Sun R, Zhou ZH. Structures of capsid and capsid-associated tegument complex inside the Epstein-Barr virus. Nat Microbiol 2020; 5:1285-1298. [PMID: 32719506 DOI: 10.1038/s41564-020-0758-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 06/19/2020] [Indexed: 12/20/2022]
Abstract
As the first discovered human cancer virus, Epstein-Barr virus (EBV) causes Burkitt's lymphoma and nasopharyngeal carcinoma. Isolating virions for determining high-resolution structures has been hindered by latency-a hallmark of EBV infection-and atomic structures are thus available only for recombinantly expressed EBV proteins. In the present study, by symmetry relaxation and subparticle reconstruction, we have determined near-atomic-resolution structures of the EBV capsid with an asymmetrically attached DNA-translocating portal and capsid-associated tegument complexes from cryogenic electron microscopy images of just 2,048 EBV virions obtained by chemical induction. The resulting atomic models reveal structural plasticity among the 20 conformers of the major capsid protein, 2 conformers of the small capsid protein (SCP), 4 conformers of the triplex monomer proteins and 2 conformers of the triplex dimer proteins. Plasticity reaches the greatest level at the capsid-tegument interfaces involving SCP and capsid-associated tegument complexes (CATC): SCPs crown pentons/hexons and mediate tegument protein binding, and CATCs bind and rotate all five periportal triplexes, but notably only about one peri-penton triplex. These results offer insights into the EBV capsid assembly and a mechanism for recruiting cell-regulating factors into the tegument compartment as 'cargoes', and should inform future anti-EBV strategies.
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Affiliation(s)
- Wei Liu
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Microbiology Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA.,Center for Integrative Imaging, Hefei National Laboratory for Physical Sciences at the Microscale, and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Yanxiang Cui
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Caiyan Wang
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Microbiology Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA.,International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zihang Li
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Microbiology Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA
| | - Danyang Gong
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Therapeutics Discovery, Amgen Research, Amgen Inc., Thousand Oaks, CA, USA
| | - Xinghong Dai
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Microbiology Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Guo-Qiang Bi
- Center for Integrative Imaging, Hefei National Laboratory for Physical Sciences at the Microscale, and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Ren Sun
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Z Hong Zhou
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA. .,Department of Microbiology Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA.
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28
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Chen J, Longnecker R. Epithelial cell infection by Epstein-Barr virus. FEMS Microbiol Rev 2020; 43:674-683. [PMID: 31584659 DOI: 10.1093/femsre/fuz023] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 10/02/2019] [Indexed: 12/13/2022] Open
Abstract
Epstein-Barr Virus (EBV) is etiologically associated with multiple human malignancies including Burkitt lymphoma and Hodgkin disease as well as nasopharyngeal and gastric carcinoma. Entry of EBV into target cells is essential for virus to cause disease and is mediated by multiple viral envelope glycoproteins and cell surface associated receptors. The target cells of EBV include B cells and epithelial cells. The nature and mechanism of EBV entry into these cell types are different, requiring different glycoprotein complexes to bind to specific receptors on the target cells. Compared to the B cell entry mechanism, the overall mechanism of EBV entry into epithelial cells is less well known. Numerous receptors have been implicated in this process and may also be involved in additional processes of EBV entry, transport, and replication. This review summarizes EBV glycoproteins, host receptors, signal molecules and transport machinery that are being used in the epithelial cell entry process and also provides a broad view for related herpesvirus entry mechanisms.
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Affiliation(s)
- Jia Chen
- Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Richard Longnecker
- Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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29
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Wang J, Zheng X, Peng Q, Zhang X, Qin Z. Eph receptors: the bridge linking host and virus. Cell Mol Life Sci 2020; 77:2355-2365. [PMID: 31893311 PMCID: PMC7275029 DOI: 10.1007/s00018-019-03409-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 11/17/2019] [Accepted: 12/02/2019] [Indexed: 02/06/2023]
Abstract
Eph (erythropoietin-producing hepatoma) receptors and Ephrin ligands constitute the largest subfamily of receptor tyrosine kinase (RTK), which were first discovered in tumors. Heretofore, Eph protein has been shown to be involved in various tumor biological behaviors including proliferation and progression. The occurrence of specific types of tumor is closely related to the virus infection. Virus entry is a complex process characterized by a series of events. The entry into target cells is an essential step for virus to cause diseases, which requires the fusion of the viral envelope and host cellular membrane mediated by viral glycoproteins and cellular receptors. Integrin molecules are well known as entry receptors for most herpes viruses. However, in recent years, Eph receptors and their Ephrin ligands have been reported to be involved in virus infections. The main mechanism may be the interaction between Eph receptors and conserved viral surface glycoprotein, such as the gH/gL or gB protein of the herpesviridae. This review focuses on the relationship between Eph receptor family and virus infection that summarize the processes of viruses such as EBV, KSHV, HCV, RRV, etc., infecting target cells through Eph receptors and activating its downstream signaling pathways resulting in malignancies. Finally, we discussed the perspectives to block virus infection, prevention, and treatment of viral-related tumors via Eph receptor family.
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Affiliation(s)
- Jia Wang
- Department of Immunology, Changzhi Medical College, Changzhi, 046000, Shanxi, China
| | - Xiang Zheng
- Department of Pathology, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China
| | - Qiu Peng
- School of Basic Medical Science, Cancer Research Institute, Central South University, Changsha, 410008, Hunan, China
| | - Xuemei Zhang
- Department of Pathology, Affiliated Hospital of Guilin Medical University, Guilin, 541001, Guangxi, China.
| | - Zailong Qin
- Laboratory of Genetics and Metabolism, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Guangxi Birth Defects Research And Prevention Institute, Nanning, 530003, Guangxi, China.
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30
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Pénzes JJ, Szirovicza L, Harrach B. The complete genome sequence of bearded dragon adenovirus 1 harbors three genes encoding proteins of the C-type lectin-like domain superfamily. INFECTION GENETICS AND EVOLUTION 2020; 83:104321. [PMID: 32302697 DOI: 10.1016/j.meegid.2020.104321] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/09/2020] [Accepted: 04/10/2020] [Indexed: 12/28/2022]
Abstract
Bearded dragon adenovirus 1 (BDAdV-1), also known as agamid adenovirus 1, has been described worldwide as a prevalent infectious agent of the inland bearded dragon (Pogona vitticeps), the most common squamate exotic pet reptile. Previous limited sequence data of the adenoviral DNA polymerase and hexon genes indicated that BDAdV-1 is a member of genus Atadenovirus family Adenoviridae. Atadenoviruses infect ruminants, marsupials, testudine reptiles and birds, yet the genus has been shown to be of squamate reptile origin. Here, we report a screening survey along with the complete genome sequence of BDAdV-1, derived directly from the sample of a deceased juvenile dragon showing central nervous system signs prior to passing. The BDAdV-1 genome is 35,276 bp and contains 32 putative genes. Its genome organization is characteristic of the members of genus Atadenovirus, however, a divergent LH3 gene indicates structural interactions of different nature compared to other genus members such as snake adenovirus 1. We identified five novel open reading frames (ORFs), three of which encode proteins of the C-type lectin-like domain (CTLD) superfamily. ORF3 has a CTLD group II-like domain architecture displaying structural similarity with natural killer cell surface receptors and with an alphaherpesviral virulence factor gene for neurotropism, UL45. ORF4 and 6 are extremely long compared to typical adenoviral right-end genes and possibly encode members of the CTLD superfamily with novel, previously undescribed domain architectures. BDAdV-1 is the hitherto most divergent member of genus Atadenovirus providing new insights on adenoviral diversity, evolution and pathogenesis.
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Affiliation(s)
- Judit J Pénzes
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary; INRS-Institut Armand-Frappier Research Centre, Laval, Quebec, Canada.
| | - Leonóra Szirovicza
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary
| | - Balázs Harrach
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary
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31
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Weed DJ, Damania B. Pathogenesis of Human Gammaherpesviruses: Recent Advances. CURRENT CLINICAL MICROBIOLOGY REPORTS 2019; 6:166-174. [PMID: 33134035 PMCID: PMC7597832 DOI: 10.1007/s40588-019-00127-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE OF THIS REVIEW Human gammaherpesviruses have complex lifecycles that drive their pathogenesis. KSHV and EBV are the etiological agents of multiple cancers worldwide. There is no FDA-approved vaccine for either KSHV or EBV. This review will describe recent progress in understanding EBV and KSHV lifecycles during infection. RECENT FINDINGS Determining how latency is established, particularly how non-coding RNAs influence latent and lytic infection, is a rapidly growing area of investigation into how gammaherpesviruses successfully persist in the human population. Many factors have been identified as restrictors of reactivation from latency, especially innate immune antagonism. Finally, new host proteins that play a role in lytic replication have been identified. SUMMARY In this review we discuss recent findings over the last 5 years on both host and viral factors that are involved in EBV and KSHV pathogenesis.
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Affiliation(s)
- Darin J Weed
- Lineberger Comprehensive Cancer Center and Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27514, USA
| | - Blossom Damania
- Lineberger Comprehensive Cancer Center and Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27514, USA
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32
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Gammaherpesvirus entry and fusion: A tale how two human pathogenic viruses enter their host cells. Adv Virus Res 2019; 104:313-343. [PMID: 31439152 DOI: 10.1016/bs.aivir.2019.05.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The prototypical human γ-herpesviruses Epstein-Barr virus (EBV) and Kaposi Sarcoma-associated herpesvirus (KSHV) are involved in the development of malignancies. Like all herpesviruses, they share the establishment of latency, the typical architecture, and the conserved fusion machinery to initiate infection. The fusion machinery reflects virus-specific adaptations due to the requirements of the respective herpesvirus. For example, EBV evolved a tropism switch involving either the B- or epithelial cell-tropism complexes to activate fusion driven by gB. Most of the EBV entry proteins and their cellular receptors have been crystallized providing molecular details of the initial steps of infection. For KSHV, a variety of entry and binding receptors has also been reported but the mechanism how receptor binding activates gB-driven fusion is not as well understood as that for EBV. However, the downstream signaling pathways that promote the early steps of KSHV entry are well described. This review summarizes the current knowledge of the key players involved in EBV and KSHV entry and the cell-type specific mechanisms that allow infection of a wide variety of cell types.
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33
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Li Q, Cohen JI. Epstein-Barr Virus and the Human Leukocyte Antigen Complex. CURRENT CLINICAL MICROBIOLOGY REPORTS 2019; 6:175-181. [PMID: 33094090 DOI: 10.1007/s40588-019-00120-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Purpose While most adults are infected Epstein-Barr virus (EBV), 3-5% remain uninfected. The human leukocyte antigen (HLA) complex, which controls many pathogens, may influence infection and disease associated with EBV. Recent Findings Numerous EBV proteins and miRNAs down-regulate HLA class I and II expression on the cell surface. HLA class II functions as a receptor for EBV entry into B cells. Specific HLA class II alleles correlate with the susceptibility of B cells to EBV infection in vitro and with EBV seropositivity or seronegativity of humans. HLA class I polymorphisms correlate with development and severity of EBV infectious mononucleosis and with the risk of several virus-associated malignancies including nasopharyngeal carcinoma, Hodgkin lymphoma, and post-transplant lymphoproliferative disease. Significance These findings indicate that while EBV has evolved to use MHC class II as a receptor for virus entry, polymorphisms in MHC class II and class I influence virus infection and disease.
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Affiliation(s)
- Qingxue Li
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Jeffrey I Cohen
- Medical Virology Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
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34
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Vallbracht M, Fuchs W, Klupp BG, Mettenleiter TC. Functional Relevance of the Transmembrane Domain and Cytoplasmic Tail of the Pseudorabies Virus Glycoprotein H for Membrane Fusion. J Virol 2018; 92:e00376-18. [PMID: 29618646 PMCID: PMC5974499 DOI: 10.1128/jvi.00376-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 03/29/2018] [Indexed: 12/18/2022] Open
Abstract
Herpesvirus membrane fusion depends on the core fusion machinery, comprised of glycoproteins B (gB) and gH/gL. Although gB structurally resembles autonomous class III fusion proteins, it strictly depends on gH/gL to drive membrane fusion. Whether the gH/gL complex needs to be membrane anchored to fulfill its function and which role the gH cytoplasmic (CD) and transmembrane domains (TMD) play in fusion is unclear. While the gH CD and TMD play an important role during infection, soluble gH/gL of herpes simplex virus 1 (HSV-1) seems to be sufficient to mediate cell-cell fusion in transient assays, arguing against an essential contribution of the CD and TMD. To shed more light on this apparent discrepancy, we investigated the role of the CD and TMD of the related alphaherpesvirus pseudorabies virus (PrV) gH. For this purpose, we expressed C-terminally truncated and soluble gH and replaced the TMD with a glycosylphosphatidylinositol (gpi) anchor. We also generated chimeras containing the TMD and/or CD of PrV gD or HSV-1 gH. Proteins were characterized in cell-based fusion assays and during virus infection. Although truncation of the CD resulted in decreased membrane fusion activity, the mutant proteins still supported replication of gH-negative PrV, indicating that the PrV gH CD is dispensable for viral replication. In contrast, PrV gH lacking the TMD, membrane-anchored via a lipid linker, or comprising the PrV gD TMD were nonfunctional, highlighting the essential role of the gH TMD for function. Interestingly, despite low sequence identity, the HSV-1 gH TMD could substitute for the PrV gH TMD, pointing to functional conservation.IMPORTANCE Enveloped viruses depend on membrane fusion for virus entry. While this process can be mediated by only one or two proteins, herpesviruses depend on the concerted action of at least three different glycoproteins. Although gB has features of bona fide fusion proteins, it depends on gH and its complex partner, gL, for fusion. Whether gH/gL prevents premature fusion or actively triggers gB-mediated fusion is unclear, and there are contradictory results on whether gH/gL function requires stable membrane anchorage or whether the ectodomains alone are sufficient. Our results show that in pseudorabies virus gH, the transmembrane anchor plays an essential role for gB-mediated fusion while the cytoplasmic tail is not strictly required.
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Affiliation(s)
- Melina Vallbracht
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Walter Fuchs
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Barbara G Klupp
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Thomas C Mettenleiter
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
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35
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Górski A, Międzybrodzki R, Jończyk-Matysiak E, Weber-Dąbrowska B, Bagińska N, Borysowski J. Perspectives of Phage-Eukaryotic Cell Interactions to Control Epstein-Barr Virus Infections. Front Microbiol 2018; 9:630. [PMID: 29666617 PMCID: PMC5891836 DOI: 10.3389/fmicb.2018.00630] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 03/19/2018] [Indexed: 12/11/2022] Open
Abstract
Recently, leading medical journals emphasized the importance of further studies on the potential application of bacterial viruses (phages) for the treatment of antibiotics-resistant infections outlining the present status of the therapy and perspectives for the future. Furthermore, a leading scientific journal pointed to the recent progress in research on phage interactions with eukaryotic cells (especially cells of the immune system) and potential implications of their results for our broader understanding of the role of phages – not only as “bacteria eaters” – but also as an important part of our body defense protecting against external and internal pathogenic invaders (as suggested previously). This illustrates how our understanding of the actual role and potential of phages is expanding and how worldwide interest in their use in medicine is growing. In this article we envision how this advancement of our knowledge about phages could be translated into the progress in combating herpesvirus infections especially those caused by Epstein–Barr virus (EBV).
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Affiliation(s)
- Andrzej Górski
- Bacteriophage Laboratory, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.,Phage Therapy Unit, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.,Department of Clinical Immunology, Transplantation Institute, Medical University of Warsaw, Warsaw, Poland
| | - Ryszard Międzybrodzki
- Bacteriophage Laboratory, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.,Phage Therapy Unit, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.,Department of Clinical Immunology, Transplantation Institute, Medical University of Warsaw, Warsaw, Poland
| | - Ewa Jończyk-Matysiak
- Bacteriophage Laboratory, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Beata Weber-Dąbrowska
- Bacteriophage Laboratory, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.,Phage Therapy Unit, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Natalia Bagińska
- Bacteriophage Laboratory, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Jan Borysowski
- Department of Clinical Immunology, Transplantation Institute, Medical University of Warsaw, Warsaw, Poland
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Human MHC-II with Shared Epitope Motifs Are Optimal Epstein-Barr Virus Glycoprotein 42 Ligands-Relation to Rheumatoid Arthritis. Int J Mol Sci 2018; 19:ijms19010317. [PMID: 29361739 PMCID: PMC5796260 DOI: 10.3390/ijms19010317] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 01/15/2018] [Accepted: 01/17/2018] [Indexed: 12/14/2022] Open
Abstract
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disorder of unknown etiology, which is characterized by inflammation in the synovium and joint damage. Although the pathogenesis of RA remains to be determined, a combination of environmental (e.g., viral infections) and genetic factors influence disease onset. Especially genetic factors play a vital role in the onset of disease, as the heritability of RA is 50–60%, with the human leukocyte antigen (HLA) alleles accounting for at least 30% of the overall genetic risk. Some HLA-DR alleles encode a conserved sequence of amino acids, referred to as the shared epitope (SE) structure. By analyzing the structure of a HLA-DR molecule in complex with Epstein-Barr virus (EBV), the SE motif is suggested to play a vital role in the interaction of MHC II with the viral glycoprotein (gp) 42, an essential entry factor for EBV. EBV has been repeatedly linked to RA by several lines of evidence and, based on several findings, we suggest that EBV is able to induce the onset of RA in predisposed SE-positive individuals, by promoting entry of B-cells through direct contact between SE and gp42 in the entry complex.
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Vallbracht M, Brun D, Tassinari M, Vaney MC, Pehau-Arnaudet G, Guardado-Calvo P, Haouz A, Klupp BG, Mettenleiter TC, Rey FA, Backovic M. Structure-Function Dissection of Pseudorabies Virus Glycoprotein B Fusion Loops. J Virol 2018; 92:e01203-17. [PMID: 29046441 PMCID: PMC5730762 DOI: 10.1128/jvi.01203-17] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 10/03/2017] [Indexed: 01/31/2023] Open
Abstract
Conserved across the family Herpesviridae, glycoprotein B (gB) is responsible for driving fusion of the viral envelope with the host cell membrane for entry upon receptor binding and activation by the viral gH/gL complex. Although crystal structures of the gB ectodomains of several herpesviruses have been reported, the membrane fusion mechanism has remained elusive. Here, we report the X-ray structure of the pseudorabies virus (PrV) gB ectodomain, revealing a typical class III postfusion trimer that binds membranes via its fusion loops (FLs) in a cholesterol-dependent manner. Mutagenesis of FL residues allowed us to dissect those interacting with distinct subregions of the lipid bilayer and their roles in membrane interactions. We tested 15 gB variants for the ability to bind to liposomes and further investigated a subset of them in functional assays. We found that PrV gB FL residues Trp187, Tyr192, Phe275, and Tyr276, which were essential for liposome binding and for fusion in cellular and viral contexts, form a continuous hydrophobic patch at the gB trimer surface. Together with results reported for other alphaherpesvirus gBs, our data suggest a model in which Phe275 from the tip of FL2 protrudes deeper into the hydrocarbon core of the lipid bilayer, while the side chains of Trp187, Tyr192, and Tyr276 form a rim that inserts into the more superficial interfacial region of the membrane to catalyze the fusion process. Comparative analysis with gBs from beta- and gamma-herpesviruses suggests that this membrane interaction model is valid for gBs from all herpesviruses.IMPORTANCE Herpesviruses are common human and animal pathogens that infect cells by entering via fusion of viral and cellular membranes. Central to the membrane fusion event is glycoprotein B (gB), which is the most conserved envelope protein across the herpesvirus family. Like other viral fusion proteins, gB anchors itself in the target membrane via two polypeptide segments called fusion loops (FLs). The molecular details of how gB FLs insert into the lipid bilayer have not been described. Here, we provide structural and functional data regarding key FL residues of gB from pseudorabies virus, a porcine herpesvirus of veterinary concern, which allows us to propose, for the first time, a molecular model to understand how the initial interactions by gBs from all herpesviruses with target membranes are established.
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Affiliation(s)
- Melina Vallbracht
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Delphine Brun
- Institut Pasteur, Unité de Virologie Structurale, Département de Virologie, Paris, France
- CNRS UMR3569, Paris, France
| | - Matteo Tassinari
- Institut Pasteur, Unité de Virologie Structurale, Département de Virologie, Paris, France
- CNRS UMR3569, Paris, France
| | - Marie-Christine Vaney
- Institut Pasteur, Unité de Virologie Structurale, Département de Virologie, Paris, France
- CNRS UMR3569, Paris, France
| | - Gérard Pehau-Arnaudet
- Institut Pasteur, Ultrapole, Département de Biologie Cellulaire et Infection, Paris, France
- CNRS UMR3528, Paris, France
| | - Pablo Guardado-Calvo
- Institut Pasteur, Unité de Virologie Structurale, Département de Virologie, Paris, France
- CNRS UMR3569, Paris, France
| | - Ahmed Haouz
- CNRS UMR3528, Paris, France
- Institut Pasteur, Plate-Forme de Cristallographie, Paris, France
| | - Barbara G Klupp
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Thomas C Mettenleiter
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
| | - Felix A Rey
- Institut Pasteur, Unité de Virologie Structurale, Département de Virologie, Paris, France
- CNRS UMR3569, Paris, France
| | - Marija Backovic
- Institut Pasteur, Unité de Virologie Structurale, Département de Virologie, Paris, France
- CNRS UMR3569, Paris, France
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Ephrin receptor A2 is a functional entry receptor for Epstein-Barr virus. Nat Microbiol 2018; 3:172-180. [PMID: 29292384 PMCID: PMC5972547 DOI: 10.1038/s41564-017-0081-7] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 11/21/2017] [Indexed: 12/20/2022]
Abstract
Epstein-Barr virus (EBV) is an oncogenic virus that infects more than 90% of the world’s population1. EBV predominantly infects human B cells and epithelial cells, which is initiated by fusion of the viral envelope with a host cellular membrane2. The mechanism of EBV entry into B cells has been well characterized3. However, the mechanism for epithelial cell entry remains elusive. Here, we show that the integrins (αvβ5, αvβ6, and αvβ8) do not function as an entry and fusion receptor for epithelial cells whereas ephrin receptor tyrosine kinase A2 (EphA2) functions well for both. EphA2 overexpression significantly increased EBV infection of HEK 293 cells. Using a virus-free cell-cell fusion assay, we found that EphA2 dramatically promoted EBV but not HSV fusion with HEK293 cells. EphA2 silencing using shRNA or knockout by CRISPR/Cas9 blocked fusion with epithelial cells. This inhibitory effect was rescued by the expression of EphA2. Antibody against EphA2 blocked epithelial cell infection. Using label-free Surface Plasmon Resonance (SPR) binding studies, we confirmed that EphA2 but not EphA4 specifically bound to EBV gHgL and this interaction is through the EphA2 extracellular domain (EphA2-ECD). The discovery of EphA2 as an EBV epithelial cell receptor has important implications for EBV pathogenesis and may uncover new potential targets that can be used for the development of novel interventional strategies.
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Sallah N, Carstensen T, Wakeham K, Bagni R, Labo N, Pollard MO, Gurdasani D, Ekoru K, Pomilla C, Young EH, Fatumo S, Asiki G, Kamali A, Sandhu M, Kellam P, Whitby D, Barroso I, Newton R. Whole-genome association study of antibody response to Epstein-Barr virus in an African population: a pilot. Glob Health Epidemiol Genom 2017; 2:e18. [PMID: 29868224 PMCID: PMC5870407 DOI: 10.1017/gheg.2017.16] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 10/19/2017] [Accepted: 10/24/2017] [Indexed: 02/02/2023] Open
Abstract
Epstein Barr virus (EBV) infects 95% of the global population and is associated with up to 2% of cancers globally. Immunoglobulin G (IgG) antibody levels to EBV have been shown to be heritable and associated with developing malignancies. We, therefore, performed a pilot genome-wide association analysis of anti-EBV IgG traits in an African population, using a combined approach including array genotyping, whole-genome sequencing and imputation to a panel with African sequence data. In 1562 Ugandans, we identify a variant in human leukocyte antigen (HLA)-DQA1, rs9272371 (p = 2.6 × 10-17) associated with anti-EBV nuclear antigen-1 responses. Trans-ancestry meta-analysis and fine-mapping with European-ancestry individuals suggest the presence of distinct HLA class II variants driving associations in Uganda. In addition, we identify four putative, novel, very rare African-specific loci with preliminary evidence for association with anti-viral capsid antigen IgG responses which will require replication for validation. These findings reinforce the need for the expansion of such studies in African populations with relevant datasets to capture genetic diversity.
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Affiliation(s)
- N. Sallah
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Virus Genomics, Wellcome Trust Sanger Institute, Hinxton, UK
| | - T. Carstensen
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - K. Wakeham
- MRC/Uganda Virus Research Institute, Uganda Research Unit on AIDS, Entebbe, Uganda
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - R. Bagni
- Protein Expression Lab, Cancer Research Technology Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - N. Labo
- Viral Oncology Section, Aids and Cancer Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - M. O. Pollard
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - D. Gurdasani
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - K. Ekoru
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - C. Pomilla
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - E. H. Young
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - S. Fatumo
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
- H3Africa Bioinformatics Network (H3ABioNet) Node, National Biotechnology Development Agency (NABDA), Federal Ministry of Science and Technology (FMST), Abuja, Nigeria
| | - G. Asiki
- MRC/Uganda Virus Research Institute, Uganda Research Unit on AIDS, Entebbe, Uganda
| | - A. Kamali
- MRC/Uganda Virus Research Institute, Uganda Research Unit on AIDS, Entebbe, Uganda
| | - M. Sandhu
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - P. Kellam
- Department of Virus Genomics, Wellcome Trust Sanger Institute, Hinxton, UK
| | - D. Whitby
- Viral Oncology Section, Aids and Cancer Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - I. Barroso
- Department of Human Genetics, Wellcome Trust Sanger Institute, Hinxton, UK
| | - R. Newton
- MRC/Uganda Virus Research Institute, Uganda Research Unit on AIDS, Entebbe, Uganda
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Computer-Aided Design of an Epitope-Based Vaccine against Epstein-Barr Virus. J Immunol Res 2017; 2017:9363750. [PMID: 29119120 PMCID: PMC5651165 DOI: 10.1155/2017/9363750] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 08/07/2017] [Accepted: 08/20/2017] [Indexed: 02/06/2023] Open
Abstract
Epstein-Barr virus is a very common human virus that infects 90% of human adults. EBV replicates in epithelial and B cells and causes infectious mononucleosis. EBV infection is also linked to various cancers, including Burkitt's lymphoma and nasopharyngeal carcinomas, and autoimmune diseases such as multiple sclerosis. Currently, there are no effective drugs or vaccines to treat or prevent EBV infection. Herein, we applied a computer-aided strategy to design a prophylactic epitope vaccine ensemble from experimentally defined T and B cell epitopes. Such strategy relies on identifying conserved epitopes in conjunction with predictions of HLA presentation for T cell epitope selection and calculations of accessibility and flexibility for B cell epitope selection. The T cell component includes 14 CD8 T cell epitopes from early antigens and 4 CD4 T cell epitopes, targeted during the course of a natural infection and providing a population protection coverage of over 95% and 81.8%, respectively. The B cell component consists of 3 experimentally defined B cell epitopes from gp350 plus 4 predicted B cell epitopes from other EBV envelope glycoproteins, all mapping in flexible and solvent accessible regions. We discuss the rationale for the formulation and possible deployment of this epitope vaccine ensemble.
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41
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Abstract
Herpesvirus entry into cells requires the coordinated action of multiple virus envelope glycoproteins, including gH, gL, and gB. For EBV, the gp42 protein assembles into complexes with gHgL heterodimers and binds HLA class II to activate gB-mediated membrane fusion with B cells. EBV tropism is dictated by gp42 levels in the virion, as it inhibits entry into epithelial cells while promoting entry into B cells. The gHgL and gB proteins are targets of neutralizing antibodies and potential candidates for subunit vaccine development, but our understanding of their neutralizing epitopes and the mechanisms of inhibition remain relatively unexplored. Here we studied the structures and mechanisms of two anti-gHgL antibodies, CL40 and CL59, that block membrane fusion with both B cells and epithelial cells. We determined the structures of the CL40 and CL59 complexes with gHgL using X-ray crystallography and EM to identify their epitope locations. CL59 binds to the C-terminal domain IV of gH, while CL40 binds to a site occupied by the gp42 receptor binding domain. CL40 binding to gHgL/gp42 complexes is not blocked by gp42 and does not interfere with gp42 binding to HLA class II, indicating that its ability to block membrane fusion with B cells represents a defect in gB activation. These data indicate that anti-gHgL neutralizing antibodies can block gHgL-mediated activation of gB through different surface epitopes and mechanisms.
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42
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Abstract
Epstein-Barr virus (EBV) is a common human herpes virus known to infect the majority of the world population. Infection with EBV is often asymptomatic but can manifest in a range of pathologies from infectious mononucleosis to severe cancers of epithelial and lymphocytic origin. Indeed, in the past decade, EBV has been linked to nearly 10% of all gastric cancers. Furthermore, recent advances in high-throughput next-generation sequencing and the development of humanized mice, which effectively model EBV pathogenesis, have led to a wealth of knowledge pertaining to strain variation and host-pathogen interaction. This review highlights some recent advances in our understanding of EBV biology, focusing on new findings on the early events of infection, the role EBV plays in gastric cancer, new strain variation, and humanized mouse models of EBV infection.
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Affiliation(s)
- Brent A Stanfield
- Department of Molecular Genetics and Microbiology, Duke Center for Virology, Duke University Medical Center, Durham, NC, USA
| | - Micah A Luftig
- Department of Molecular Genetics and Microbiology, Duke Center for Virology, Duke University Medical Center, Durham, NC, USA
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43
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Li Q, Bu W, Gabriel E, Aguilar F, Hoshino Y, Miyadera H, Hess C, Hornung RL, Roy A, Cohen JI. HLA-DQ β1 alleles associated with Epstein-Barr virus (EBV) infectivity and EBV gp42 binding to cells. JCI Insight 2017; 2:e85687. [PMID: 28239644 PMCID: PMC5313076 DOI: 10.1172/jci.insight.85687] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 01/05/2017] [Indexed: 11/17/2022] Open
Abstract
Epstein-Barr virus (EBV) infects B cells and ~95% of adults are infected. EBV glycoprotein gp42 is essential for entry of virus into B cells. EBV gp42 binds to the β1 chain of HLA-DQ, -DR, and -DP on B cells, and uses these molecules for infection. To investigate if certain HLA-DQ alleles are associated with EBV seronegativity, we recruited ~3,300 healthy adult blood donors, identified 106 EBV-seronegative individuals, and randomly selected a control group of EBV-seropositive donors from the donor pool. A larger than expected proportion of EBV-seronegative subjects were HLA-DQ β1 *04/*05 and *06/*06, and to a lesser extent, *02/*03, compared with the control group, while a larger than expected portion of EBV-seropositive persons were HLA-DQ β1 *02/*02. We examined the ability of EBV gp42 to bind to different HLA-DQ molecules using human and mouse cells stably expressing these alleles. EBV gp42 bound less effectively to cells expressing HLA-DQ β1 *04/*05, *06/*06, or *03/*03 than to cells expressing HLA-DQ β1 *02/*02. These data are consistent with our observations of increased EBV seronegativity with DQ β1 *04/*05 or *06/*06 alleles. These findings emphasize the importance of a single genetic locus (HLA-DQ β1) to influence infectivity with EBV.
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Affiliation(s)
- Qingxue Li
- Medical Virology Section, Laboratory of Infectious Diseases
| | - Wei Bu
- Medical Virology Section, Laboratory of Infectious Diseases
| | - Erin Gabriel
- Division of Clinical Research, Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Fiona Aguilar
- Medical Virology Section, Laboratory of Infectious Diseases
| | - Yo Hoshino
- Medical Virology Section, Laboratory of Infectious Diseases
| | - Hiroko Miyadera
- Department of Human Genetics, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
- Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, Japan
| | - Christoph Hess
- Immunobiology Laboratory, Department of Biomedicine, and Medical Outpatient Division, University Hospital Basel, Basel, Switzerland
| | - Ronald L. Hornung
- Clinical Services Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Amitava Roy
- Bioinformatics and Computational Biosciences Branch, Rocky Mountain Laboratories, NIH, Hamilton, Montana, USA
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Structural basis for Epstein-Barr virus host cell tropism mediated by gp42 and gHgL entry glycoproteins. Nat Commun 2016; 7:13557. [PMID: 27929061 PMCID: PMC5155155 DOI: 10.1038/ncomms13557] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 10/13/2016] [Indexed: 12/12/2022] Open
Abstract
Herpesvirus entry into host cells is mediated by multiple virally encoded receptor binding and membrane fusion glycoproteins. Despite their importance in host cell tropism and associated disease pathology, the underlying and essential interactions between these viral glycoproteins remain poorly understood. For Epstein–Barr virus (EBV), gHgL/gp42 complexes bind HLA class II to activate membrane fusion with B cells, but gp42 inhibits fusion and entry into epithelial cells. To clarify the mechanism by which gp42 controls the cell specificity of EBV infection, here we determined the structure of gHgL/gp42 complex bound to an anti-gHgL antibody (E1D1). The critical regulator of EBV tropism is the gp42 N-terminal domain, which tethers the HLA-binding domain to gHgL by wrapping around the exterior of three gH domains. Both the gp42 N-terminal domain and E1D1 selectively inhibit epithelial-cell fusion; however, they engage distinct surfaces of gHgL. These observations clarify key determinants of EBV host cell tropism.
The entry of herpesviruses (such as Epstein-Barr virus) into host cells is mediated by a multitude of glycoproteins. Here, the authors show the structure of a viral glycoprotein complex, gHgL/gp42, bound to an anti-gHgL antibody, clarifying determinants of EBV host cell tropism.
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45
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Campadelli-Fiume G, Collins-McMillen D, Gianni T, Yurochko AD. Integrins as Herpesvirus Receptors and Mediators of the Host Signalosome. Annu Rev Virol 2016; 3:215-236. [PMID: 27501260 DOI: 10.1146/annurev-virology-110615-035618] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The repertoire of herpesvirus receptors consists of nonintegrin and integrin molecules. Integrins interact with the conserved glycoproteins gH/gL or gB. This interaction is a conserved biology across the Herpesviridae family, likely directed to promote virus entry and endocytosis. Herpesviruses exploit this interaction to execute a range of critical functions that include (a) relocation of nonintegrin receptors (e.g., herpes simplex virus nectin1 and Kaposi's sarcoma-associated herpesvirus EphA2), or association with nonintegrin receptors (i.e., human cytomegalovirus EGFR), to dictate species-specific entry pathways; (b) activation of multiple signaling pathways (e.g., Ca2+ release, c-Src, FAK, MAPK, and PI3K); and (c) association with Rho GTPases, tyrosine kinase receptors, Toll-like receptors, which result in cytoskeletal remodeling, differential cell type targeting, and innate responses. In turn, integrins can be modulated by viral proteins (e.g., Epstein-Barr virus LMPs) to favor spread of transformed cells. We propose that herpesviruses evolved a multipartite entry system to allow interaction with multiple receptors, including integrins, required for their sophisticated life cycle.
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Affiliation(s)
- Gabriella Campadelli-Fiume
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy;
| | - Donna Collins-McMillen
- Department of Microbiology and Immunology, Center for Molecular and Tumor Virology, and Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130;
| | - Tatiana Gianni
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy;
| | - Andrew D Yurochko
- Department of Microbiology and Immunology, Center for Molecular and Tumor Virology, and Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130; .,Feist-Weiller Cancer Center and Center for Excellence in Arthritis and Rheumatology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130
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46
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Forsyth KS, Eisenlohr LC. Giving CD4+ T cells the slip: viral interference with MHC class II-restricted antigen processing and presentation. Curr Opin Immunol 2016; 40:123-9. [PMID: 27115617 PMCID: PMC4894315 DOI: 10.1016/j.coi.2016.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Accepted: 03/08/2016] [Indexed: 01/18/2023]
Abstract
Activation of CD4+ T cells through interactions with peptides bound to Major Histocompatibility Complex Class II (MHC-II) molecules is a crucial step in clearance of most pathogens. Consequently, many viruses have evolved ways of blocking this aspect of adaptive immunity, from specific targeting of processing and presentation components to modulation of signaling pathways that regulate peptide presentation in addition to many other host defense mechanisms. Such cases of interference are far less common compared to what has been elucidated in MHC-I processing and presentation. This may be attributable in part to the complexity of MHC-II antigen processing, the scope of which is only now coming to light.
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Affiliation(s)
- Katherine S Forsyth
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Laurence C Eisenlohr
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Department of Pathology and Laboratory Medicine at the Children's Hospital of Philadelphia Research Institute, Philadelphia, PA, United States.
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47
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Möhl BS, Chen J, Sathiyamoorthy K, Jardetzky TS, Longnecker R. Structural and Mechanistic Insights into the Tropism of Epstein-Barr Virus. Mol Cells 2016; 39:286-91. [PMID: 27094060 PMCID: PMC4844934 DOI: 10.14348/molcells.2016.0066] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 03/26/2016] [Indexed: 01/23/2023] Open
Abstract
Epstein-Barr virus (EBV) is the prototypical γ-herpesvirus and an obligate human pathogen that infects mainly epithelial cells and B cells, which can result in malignancies. EBV infects these target cells by fusing with the viral and cellular lipid bilayer membranes using multiple viral factors and host receptor(s) thus exhibiting a unique complexity in its entry machinery. To enter epithelial cells, EBV requires minimally the conserved core fusion machinery comprised of the glycoproteins gH/gL acting as the receptor-binding complex and gB as the fusogen. EBV can enter B cells using gp42, which binds tightly to gH/gL and interacts with host HLA class II, activating fusion. Previously, we published the individual crystal structures of EBV entry factors, such as gH/gL and gp42, the EBV/host receptor complex, gp42/HLA-DR1, and the fusion protein EBV gB in a postfusion conformation, which allowed us to identify structural determinants and regions critical for receptor-binding and membrane fusion. Recently, we reported different low resolution models of the EBV B cell entry triggering complex (gHgL/gp42/HLA class II) in "open" and "closed" states based on negative-stain single particle electron microscopy, which provide further mechanistic insights. This review summarizes the current knowledge of these key players in EBV entry and how their structures impact receptor-binding and the triggering of gB-mediated fusion.
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Affiliation(s)
- Britta S. Möhl
- Department of Microbiology and Immunology, The Feinberg School of Medicine, Northwestern University, Chicago, Illinois,
USA
| | - Jia Chen
- Department of Microbiology and Immunology, The Feinberg School of Medicine, Northwestern University, Chicago, Illinois,
USA
| | - Karthik Sathiyamoorthy
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California,
USA
| | - Theodore S. Jardetzky
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California,
USA
| | - Richard Longnecker
- Department of Microbiology and Immunology, The Feinberg School of Medicine, Northwestern University, Chicago, Illinois,
USA
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48
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Heldwein EE. gH/gL supercomplexes at early stages of herpesvirus entry. Curr Opin Virol 2016; 18:1-8. [PMID: 26849495 DOI: 10.1016/j.coviro.2016.01.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 01/14/2016] [Accepted: 01/15/2016] [Indexed: 11/25/2022]
Abstract
Membrane fusion during herpesvirus entry into host cells is a complex process where multiple glycoproteins interact to relay the triggering signal from a receptor-binding protein to the conserved fusogen gB through the conserved heterodimer gH/gL. Crystal structures of individual glycoproteins are available, yet high-order 'supercomplexes' have been elusive. Recent structures of complexes between gH/gL from human cytomegalovirus or Epstein-Barr virus and the receptor-binding proteins that form at early stages of herpesviral entry highlighted mechanisms that control tropism and revealed dynamic intermediate complexes containing gH/gL that may directly participate in membrane deformation and juxtaposition. Determining how the triggering signal reaches the fusogen gB represents the next frontier in structural biology of herpesvirus entry.
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Affiliation(s)
- Ekaterina E Heldwein
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA.
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49
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Herpesvirus gB: A Finely Tuned Fusion Machine. Viruses 2015; 7:6552-69. [PMID: 26690469 PMCID: PMC4690880 DOI: 10.3390/v7122957] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 11/15/2015] [Accepted: 11/27/2015] [Indexed: 01/03/2023] Open
Abstract
Enveloped viruses employ a class of proteins known as fusogens to orchestrate the merger of their surrounding envelope and a target cell membrane. Most fusogens accomplish this task alone, by binding cellular receptors and subsequently catalyzing the membrane fusion process. Surprisingly, in herpesviruses, these functions are distributed among multiple proteins: the conserved fusogen gB, the conserved gH/gL heterodimer of poorly defined function, and various non-conserved receptor-binding proteins. We summarize what is currently known about gB from two closely related herpesviruses, HSV-1 and HSV-2, with emphasis on the structure of the largely uncharted membrane interacting regions of this fusogen. We propose that the unusual mechanism of herpesvirus fusion could be linked to the unique architecture of gB.
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50
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Abstract
Glycoproteins are critical to virus entry, to spread within and between hosts and can modify the behavior of cells. Many viruses carry only a few, most found in the virion envelope. EBV makes more than 12, providing flexibility in how it colonizes its human host. Some are dedicated to getting the virus through the cell membrane and on toward the nucleus of the cell, some help guide the virus back out and on to the next cell in the same or a new host. Yet others undermine host defenses helping the virus persist for a lifetime, maintaining a presence that is mostly tolerated and serves to perpetuate EBV as one of the most common infections of man.
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Affiliation(s)
- Lindsey M Hutt-Fletcher
- Department of Microbiology & Immunology, Feist-Weiller Cancer Center and Center for Molecular & Tumor Virology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA; Tel.: +1 318 675 4948
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