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Escudero-Flórez M, Torres-Hoyos D, Miranda-Brand Y, Boudreau RL, Gallego-Gómez JC, Vicente-Manzanares M. Dengue Virus Infection Alters Inter-Endothelial Junctions and Promotes Endothelial-Mesenchymal-Transition-Like Changes in Human Microvascular Endothelial Cells. Viruses 2023; 15:1437. [PMID: 37515125 PMCID: PMC10386726 DOI: 10.3390/v15071437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 06/19/2023] [Accepted: 06/23/2023] [Indexed: 07/30/2023] Open
Abstract
Dengue virus (DENV) is a pathogenic arbovirus that causes human disease. The most severe stage of the disease (severe dengue) is characterized by vascular leakage, hypovolemic shock, and organ failure. Endothelial dysfunction underlies these phenomena, but the causal mechanisms of endothelial dysfunction are poorly characterized. This study investigated the role of c-ABL kinase in DENV-induced endothelial dysfunction. Silencing c-ABL with artificial miRNA or targeting its catalytic activity with imatinib revealed that c-ABL is required for the early steps of DENV infection. DENV-2 infection and conditioned media from DENV-infected cells increased endothelial expression of c-ABL and CRKII phosphorylation, promoted expression of mesenchymal markers, e.g., vimentin and N-cadherin, and decreased the levels of endothelial-specific proteins, e.g., VE-cadherin and ZO-1. These effects were reverted by silencing or inhibiting c-ABL. As part of the acquisition of a mesenchymal phenotype, DENV infection and treatment with conditioned media from DENV-infected cells increased endothelial cell motility in a c-ABL-dependent manner. In conclusion, DENV infection promotes a c-ABL-dependent endothelial phenotypic change that leads to the loss of intercellular junctions and acquisition of motility.
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Affiliation(s)
- Manuela Escudero-Flórez
- Molecular and Translation Medicine Group, University of Antioquia, Medellin 050010, Colombia; (M.E.-F.); (D.T.-H.); (Y.M.-B.)
| | - David Torres-Hoyos
- Molecular and Translation Medicine Group, University of Antioquia, Medellin 050010, Colombia; (M.E.-F.); (D.T.-H.); (Y.M.-B.)
| | - Yaneth Miranda-Brand
- Molecular and Translation Medicine Group, University of Antioquia, Medellin 050010, Colombia; (M.E.-F.); (D.T.-H.); (Y.M.-B.)
| | - Ryan L. Boudreau
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA;
| | - Juan Carlos Gallego-Gómez
- Molecular and Translation Medicine Group, University of Antioquia, Medellin 050010, Colombia; (M.E.-F.); (D.T.-H.); (Y.M.-B.)
| | - Miguel Vicente-Manzanares
- Molecular Mechanisms Program, Centro de Investigación del Cáncer, Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Salamanca, 37007 Salamanca, Spain
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Lauver MD, Goetschius DJ, Netherby-Winslow CS, Ayers KN, Jin G, Haas DG, Frost EL, Cho SH, Bator CM, Bywaters SM, Christensen ND, Hafenstein SL, Lukacher AE. Antibody escape by polyomavirus capsid mutation facilitates neurovirulence. eLife 2020; 9:e61056. [PMID: 32940605 PMCID: PMC7541085 DOI: 10.7554/elife.61056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/17/2020] [Indexed: 12/27/2022] Open
Abstract
JCPyV polyomavirus, a member of the human virome, causes progressive multifocal leukoencephalopathy (PML), an oft-fatal demyelinating brain disease in individuals receiving immunomodulatory therapies. Mutations in the major viral capsid protein, VP1, are common in JCPyV from PML patients (JCPyV-PML) but whether they confer neurovirulence or escape from virus-neutralizing antibody (nAb) in vivo is unknown. A mouse polyomavirus (MuPyV) with a sequence-equivalent JCPyV-PML VP1 mutation replicated poorly in the kidney, a major reservoir for JCPyV persistence, but retained the CNS infectivity, cell tropism, and neuropathology of the parental virus. This mutation rendered MuPyV resistant to a monoclonal Ab (mAb), whose specificity overlapped the endogenous anti-VP1 response. Using cryo-EM and a custom sub-particle refinement approach, we resolved an MuPyV:Fab complex map to 3.2 Å resolution. The structure revealed the mechanism of mAb evasion. Our findings demonstrate convergence between nAb evasion and CNS neurovirulence in vivo by a frequent JCPyV-PML VP1 mutation.
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Affiliation(s)
- Matthew D Lauver
- Department of Microbiology and Immunology, Penn State College of MedicineHersheyUnited States
| | - Daniel J Goetschius
- Department of Biochemistry and Molecular Biology, Pennsylvania State UniversityUniversity ParkUnited States
| | | | - Katelyn N Ayers
- Department of Microbiology and Immunology, Penn State College of MedicineHersheyUnited States
| | - Ge Jin
- Department of Microbiology and Immunology, Penn State College of MedicineHersheyUnited States
| | - Daniel G Haas
- Department of Microbiology and Immunology, Penn State College of MedicineHersheyUnited States
| | - Elizabeth L Frost
- Department of Microbiology and Immunology, Penn State College of MedicineHersheyUnited States
| | - Sung Hyun Cho
- Huck Institutes of the Life Sciences, Pennsylvania State UniversityUniversity ParkUnited States
| | - Carol M Bator
- Huck Institutes of the Life Sciences, Pennsylvania State UniversityUniversity ParkUnited States
| | - Stephanie M Bywaters
- Department of Pathology, Penn State College of MedicineHersheyUnited States
- The Jake Gittlen Laboratories for Cancer Research, Penn State College of MedicineHersheyUnited States
| | - Neil D Christensen
- Department of Pathology, Penn State College of MedicineHersheyUnited States
- The Jake Gittlen Laboratories for Cancer Research, Penn State College of MedicineHersheyUnited States
| | - Susan L Hafenstein
- Department of Biochemistry and Molecular Biology, Pennsylvania State UniversityUniversity ParkUnited States
- Huck Institutes of the Life Sciences, Pennsylvania State UniversityUniversity ParkUnited States
- Department of Medicine, Penn State College of MedicineHersheyUnited States
| | - Aron E Lukacher
- Department of Microbiology and Immunology, Penn State College of MedicineHersheyUnited States
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Abstract
Antiviral drugs have traditionally been developed by directly targeting essential viral components. However, this strategy often fails due to the rapid generation of drug-resistant viruses. Recent genome-wide approaches, such as those employing small interfering RNA (siRNA) or clustered regularly interspaced short palindromic repeats (CRISPR) or those using small molecule chemical inhibitors targeting the cellular "kinome," have been used successfully to identify cellular factors that can support virus replication. Since some of these cellular factors are critical for virus replication, but are dispensable for the host, they can serve as novel targets for antiviral drug development. In addition, potentiation of immune responses, regulation of cytokine storms, and modulation of epigenetic changes upon virus infections are also feasible approaches to control infections. Because it is less likely that viruses will mutate to replace missing cellular functions, the chance of generating drug-resistant mutants with host-targeted inhibitor approaches is minimized. However, drug resistance against some host-directed agents can, in fact, occur under certain circumstances, such as long-term selection pressure of a host-directed antiviral agent that can allow the virus the opportunity to adapt to use an alternate host factor or to alter its affinity toward the target that confers resistance. This review describes novel approaches for antiviral drug development with a focus on host-directed therapies and the potential mechanisms that may account for the acquisition of antiviral drug resistance against host-directed agents.
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Hou L, Zhao J, Gao S, Ji T, Song T, Li Y, Wang J, Geng C, Long M, Chen J, Lin H, Cai X, Cang Y. Restriction of hepatitis B virus replication by c-Abl-induced proteasomal degradation of the viral polymerase. SCIENCE ADVANCES 2019; 5:eaau7130. [PMID: 30775435 PMCID: PMC6365112 DOI: 10.1126/sciadv.aau7130] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 12/19/2018] [Indexed: 05/13/2023]
Abstract
About 257 million people with chronic infection of hepatitis B virus (HBV) worldwide are at high risk of developing terminal liver diseases. Reactivation of virus replication has been frequently reported in those patient populations receiving imatinib (an Abl kinase inhibitor) or bortezomib (a proteasome inhibitor) to treat concurrent diseases, but the underlying mechanism for this reactivation is unknown. We report that the HBV polymerase protein is recruited by Cdt2 to the cullin-RING ligase 4 (CRL4) for ubiquitination and proteasome degradation and that this process is stimulated by the c-Abl nonreceptor tyrosine kinase. Genetic ablation of the Abl-CRL4Cdt2 axis or pharmaceutical inhibition of this process stabilizes HBV polymerase protein and increases viral loads in HBV-infected liver cancer cell lines. Our study reveals a kinase-dependent activation of CRL4 ubiquitin ligase that can be targeted for blocking HBV replication.
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Affiliation(s)
- Lidan Hou
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Jie Zhao
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Shaobing Gao
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
- Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan 450008, China
| | - Tong Ji
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Tianyu Song
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yining Li
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jingjie Wang
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Chenlu Geng
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Min Long
- Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jiang Chen
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Hui Lin
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiujun Cai
- Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Yong Cang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Corresponding author.
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Zhang J, Lei X, Wang D, Jiang Y, Zhan Y, Li M, Zhou Y, Qin Y, Liu J, Wang A, Yang Y, Wang N. Inhibition of Abl or Src tyrosine kinase decreased porcine circovirus type 2 production in PK15 cells. Res Vet Sci 2019; 124:1-9. [PMID: 30716585 DOI: 10.1016/j.rvsc.2019.01.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 01/14/2019] [Accepted: 01/22/2019] [Indexed: 12/12/2022]
Abstract
Porcine circovirus type 2 (PCV2) causes huge economic losses in the global swine industry and has a complex and poorly understood virus-host interaction mechanism. We reported that the C-terminal of the capsid protein of all PCV2 isolates shared a strictly conserved PXXP motif that may interact with SH3 domain-containing tyrosine kinases; however, its roles in PCV2 cell entry and replication remain unknown. In this study, we determined that mRNA levels of two SH3 domain-containing tyrosine kinases family (Abl and Src) had distinct profiles (wild-type and PXXP-mutated) during PCV2 infections of PK15 cells. Therefore, we hypothesized that activities of tyrosine kinases (Abl and Fyn) in PK15 cells may be hijacked by PCV2 via its PXXP motif of the Cap, to favor virus replication. Specific inhibitors PP2 of Lck/Fyn and STI-571 of Abl family kinases decreased viral production through suppression of DNA and Cap synthesis at the replication stage. However, based on indirect immunofluorescence assay (IFA), entry of PCV2 virus-like particles (VLPs) into PK15 cells was not altered. Elucidating mechanisms of PCV2-host interactions should provide new insights for development of new compounds to prevent or reduce PCV2 infections.
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Affiliation(s)
- Jiaxin Zhang
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Xinnuo Lei
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Dongliang Wang
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Yifan Jiang
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Yang Zhan
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Meng Li
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Yawen Zhou
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Yiwen Qin
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Jue Liu
- Beijing Key Laboratory for Prevention and Control of Infectious Diseases in Livestock and Poultry, Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, No. 9 Shuguang Garden Middle Road, Haidian District, Beijing 100097, China
| | - Aibing Wang
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Yi Yang
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China
| | - Naidong Wang
- The Key Laboratory of Animal Vaccine & Protein Engineering, College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, China.
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CD4 T cells control development and maintenance of brain-resident CD8 T cells during polyomavirus infection. PLoS Pathog 2018; 14:e1007365. [PMID: 30372487 PMCID: PMC6224182 DOI: 10.1371/journal.ppat.1007365] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 11/08/2018] [Accepted: 09/28/2018] [Indexed: 01/02/2023] Open
Abstract
Tissue-resident memory CD8 T (TRM) cells defend against microbial reinfections at mucosal barriers; determinants driving durable TRM cell responses in non-mucosal tissues, which often harbor opportunistic persistent pathogens, are unknown. JC polyomavirus (JCPyV) is a ubiquitous constituent of the human virome. With altered immunological status, JCPyV can cause the oft-fatal brain demyelinating disease progressive multifocal leukoencephalopathy (PML). JCPyV is a human-only pathogen. Using the mouse polyomavirus (MuPyV) encephalitis model, we demonstrate that CD4 T cells regulate development of functional antiviral brain-resident CD8 T cells (bTRM) and renders their maintenance refractory to systemic CD8 T cell depletion. Acquired CD4 T cell deficiency, modeled by delaying systemic CD4 T cell depletion until MuPyV-specific CD8 T cells have infiltrated the brain, impacted the stability of CD8 bTRM, impaired their effector response to reinfection, and rendered their maintenance dependent on circulating CD8 T cells. This dependence of CD8 bTRM differentiation on CD4 T cells was found to extend to encephalitis caused by vesicular stomatitis virus. Together, these findings reveal an intimate association between CD4 T cells and homeostasis of functional bTRM to CNS viral infection.
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Schor S, Einav S. Repurposing of Kinase Inhibitors as Broad-Spectrum Antiviral Drugs. DNA Cell Biol 2017; 37:63-69. [PMID: 29148875 DOI: 10.1089/dna.2017.4033] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The high cost of drug development and the narrow spectrum of coverage typically provided by direct-acting antivirals limit the scalability of this antiviral approach. This review summarizes progress and challenges in the repurposing of approved kinase inhibitors as host-targeted broad-spectrum antiviral therapies.
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Affiliation(s)
- Stanford Schor
- 1 Division of Infectious Diseases and Geographic Medicine , Department of Medicine, Stanford, California.,2 Department of Microbiology and Immunology, Stanford University School of Medicine , Stanford, California
| | - Shirit Einav
- 1 Division of Infectious Diseases and Geographic Medicine , Department of Medicine, Stanford, California.,2 Department of Microbiology and Immunology, Stanford University School of Medicine , Stanford, California
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Helle F, Brochot E, Handala L, Martin E, Castelain S, Francois C, Duverlie G. Biology of the BKPyV: An Update. Viruses 2017; 9:v9110327. [PMID: 29099746 PMCID: PMC5707534 DOI: 10.3390/v9110327] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 10/30/2017] [Accepted: 10/30/2017] [Indexed: 12/29/2022] Open
Abstract
The BK virus (BKPyV) is a member of the Polyomaviridae family first isolated in 1971. BKPyV causes frequent infections during childhood and establishes persistent infections with minimal clinical implications within renal tubular cells and the urothelium. However, reactivation of BKPyV in immunocompromised individuals may cause serious complications. In particular, with the implementation of more potent immunosuppressive drugs in the last decade, BKPyV has become an emerging pathogen in kidney and bone marrow transplant recipients where it often causes associated nephropathy and haemorrhagic cystitis, respectively. Unfortunately, no specific antiviral against BKPyV has been approved yet and the only therapeutic option is a modulation of the immunosuppressive drug regimen to improve immune control though it may increase the risk of rejection. A better understanding of the BKPyV life cycle is thus needed to develop efficient treatment against this virus. In this review, we provide an update on recent advances in understanding the biology of BKPyV.
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Affiliation(s)
- Francois Helle
- EA4294, Unité de Virologie Clinique et Fondamentale, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, 80054 Amiens, France.
| | - Etienne Brochot
- EA4294, Unité de Virologie Clinique et Fondamentale, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, 80054 Amiens, France.
| | - Lynda Handala
- EA4294, Unité de Virologie Clinique et Fondamentale, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, 80054 Amiens, France.
| | - Elodie Martin
- EA4294, Unité de Virologie Clinique et Fondamentale, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, 80054 Amiens, France.
| | - Sandrine Castelain
- EA4294, Unité de Virologie Clinique et Fondamentale, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, 80054 Amiens, France.
| | - Catherine Francois
- EA4294, Unité de Virologie Clinique et Fondamentale, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, 80054 Amiens, France.
| | - Gilles Duverlie
- EA4294, Unité de Virologie Clinique et Fondamentale, Centre Universitaire de Recherche en Santé, Centre Hospitalier Universitaire et Université de Picardie Jules Verne, 80054 Amiens, France.
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Alloimmunity But Not Viral Immunity Promotes Allograft Loss in a Mouse Model of Polyomavirus-Associated Allograft Injury. Transplant Direct 2017; 3:e161. [PMID: 28620645 PMCID: PMC5464780 DOI: 10.1097/txd.0000000000000677] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/15/2017] [Indexed: 11/30/2022] Open
Abstract
Background The interplay between viral infection and alloimmunity is known to influence the fate of transplanted organs. Clarifying how local virus-associated inflammation/injury and antiviral immunity can alter host alloimmune responses in transplantation remains a critical question. Methods We used a mouse model of polyomavirus (PyV) infection and kidney transplantation to investigate the roles of direct viral pathology, the antiviral immune response, and alloimmunity in the pathogenesis of PyV-associated allograft injury. We have previously shown that an effective primary T cell response is required in PyV-associated graft injury. Results Here we show that the transfer of primed antidonor, but not antiviral, T cells results in PyV-associated allograft injury. In further studies, we use a surrogate minor antigen model (ovalbumin) and show that only antidonor specific T cells and not antiviral specific T cells are sufficient to mediate injury. Lastly, we demonstrate that local but not systemic virus-mediated inflammation and injury within the graft itself are required. Conclusions These data suggest that in this mouse model, the predominant mechanism of allograft injury in PyV-associated injury is due to an augmented alloimmune T cell response driven by virus-induced inflammation/injury within the graft. These studies highlight the important interplay between viral infection and alloimmunity in a model system.
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Murine Polyomavirus Cell Surface Receptors Activate Distinct Signaling Pathways Required for Infection. mBio 2016; 7:mBio.01836-16. [PMID: 27803182 PMCID: PMC5090042 DOI: 10.1128/mbio.01836-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Virus binding to the cell surface triggers an array of host responses, including activation of specific signaling pathways that facilitate steps in virus entry. Using mouse polyomavirus (MuPyV), we identified host signaling pathways activated upon virus binding to mouse embryonic fibroblasts (MEFs). Pathways activated by MuPyV included the phosphatidylinositol 3-kinase (PI3K), FAK/SRC, and mitogen-activated protein kinase (MAPK) pathways. Gangliosides and α4-integrin are required receptors for MuPyV infection. MuPyV binding to both gangliosides and the α4-integrin receptors was required for activation of the PI3K pathway; however, either receptor interaction alone was sufficient for activation of the MAPK pathway. Using small-molecule inhibitors, we confirmed that the PI3K and FAK/SRC pathways were required for MuPyV infection, while the MAPK pathway was dispensable. Mechanistically, the PI3K pathway was required for MuPyV endocytosis, while the FAK/SRC pathway enabled trafficking of MuPyV along microtubules. Thus, MuPyV interactions with specific cell surface receptors facilitate activation of signaling pathways required for virus entry and trafficking. Understanding how different viruses manipulate cell signaling pathways through interactions with host receptors could lead to the identification of new therapeutic targets for viral infection. Virus binding to cell surface receptors initiates outside-in signaling that leads to virus endocytosis and subsequent virus trafficking. How different viruses manipulate cell signaling through interactions with host receptors remains unclear, and elucidation of the specific receptors and signaling pathways required for virus infection may lead to new therapeutic targets. In this study, we determined that gangliosides and α4-integrin mediate mouse polyomavirus (MuPyV) activation of host signaling pathways. Of these pathways, the PI3K and FAK/SRC pathways were required for MuPyV infection. Both the PI3K and FAK/SRC pathways have been implicated in human diseases, such as heart disease and cancer, and inhibitors directed against these pathways are currently being investigated as therapies. It is possible that these pathways play a role in human PyV infections and could be targeted to inhibit PyV infection in immunosuppressed patients.
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11
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Wetzel DM, Rhodes EL, Li S, McMahon-Pratt D, Koleske AJ. The Src kinases Hck, Fgr and Lyn activate Arg to facilitate IgG-mediated phagocytosis and Leishmania infection. J Cell Sci 2016; 129:3130-43. [PMID: 27358479 DOI: 10.1242/jcs.185595] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/23/2016] [Indexed: 12/19/2022] Open
Abstract
Leishmaniasis is a devastating disease that disfigures or kills nearly two million people each year. Establishment and persistence of infection by the obligate intracellular parasite Leishmania requires repeated uptake by macrophages and other phagocytes. Therefore, preventing uptake could be a novel therapeutic strategy for leishmaniasis. Amastigotes, the life cycle stage found in the human host, bind Fc receptors and enter macrophages primarily through immunoglobulin-mediated phagocytosis. However, the host machinery that mediates amastigote uptake is poorly understood. We have previously shown that the Arg (also known as Abl2) non-receptor tyrosine kinase facilitates L. amazonensis amastigote uptake by macrophages. Using small-molecule inhibitors and primary macrophages lacking specific Src family kinases, we now demonstrate that the Hck, Fgr and Lyn kinases are also necessary for amastigote uptake by macrophages. Src-mediated Arg activation is required for efficient uptake. Interestingly, the dual Arg and Src kinase inhibitor bosutinib, which is approved to treat cancer, not only decreases amastigote uptake, but also significantly reduces disease severity and parasite burden in Leishmania-infected mice. Our results suggest that leishmaniasis could potentially be treated with host-cell-active agents such as kinase inhibitors.
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Affiliation(s)
- Dawn M Wetzel
- Department of Pediatrics, Yale University, New Haven, CT 06520, USA
| | - Emma L Rhodes
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shaoguang Li
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Diane McMahon-Pratt
- Department of Epidemiology of Microbial Disease, Yale School of Public Health, New Haven, CT 06520, USA
| | - Anthony J Koleske
- Department of Molecular Biochemistry and Biophysics, Yale University, CT 06520, USA Department of Neuroscience, Yale University, New Haven, CT 06520, USA
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13
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Hawn TR, Shah JA, Kalman D. New tricks for old dogs: countering antibiotic resistance in tuberculosis with host-directed therapeutics. Immunol Rev 2015; 264:344-62. [PMID: 25703571 DOI: 10.1111/imr.12255] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Despite the availability of Mycobacterium tuberculosis (Mtb) drugs for over 50 years, tuberculosis (TB) remains at pandemic levels. New drugs are urgently needed for resistant strains, shortening duration of treatment, and targeting different stages of the disease, especially for treatment during human immunodeficiency virus co-infection. One solution to the conundrum that antibiotics kill the bacillus yet select for resistance is to target the host rather than the pathogen. Here, we discuss recent progress in so-called 'host-directed therapeutics' (HDTs), focusing on two general mechanistic strategies: (i) HDTs that disrupt Mtb pathogenesis in macrophages and (ii) immunomodulatory HDTs that facilitate protective immune responses that kill Mtb or reduce deleterious responses that exacerbate disease. HDTs hold significant promise as adjunctive therapies in that they are less likely to engender resistance, will likely have efficacy against antibiotic-resistant strains, and may have activity against non-replicating Mtb. However, TB is a complex and variegated disease, and human populations exhibit significant diversity in their immune responses to it, which presents a complicated landscape for HDTs to navigate. Nevertheless, we suggest that a detailed mechanistic understanding of drug action, together with careful selection of disease stage targets and dosing strategies may overcome such limitations and allow the development of HDTs as effective adjunctive treatment options for TB.
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Affiliation(s)
- Thomas R Hawn
- Department of Medicine, University of Washington, Seattle, WA, USA
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You J, O’Hara SD, Velupillai P, Castle S, Levery S, Garcea RL, Benjamin T. Ganglioside and Non-ganglioside Mediated Host Responses to the Mouse Polyomavirus. PLoS Pathog 2015; 11:e1005175. [PMID: 26474471 PMCID: PMC4608836 DOI: 10.1371/journal.ppat.1005175] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 08/28/2015] [Indexed: 11/18/2022] Open
Abstract
Gangliosides serve as receptors for internalization and infection by members of the polyomavirus family. Specificity is determined by recognition of carbohydrate moieties on the ganglioside by the major viral capsid protein VP1. For the mouse polyomavirus (MuPyV), gangliosides with terminal sialic acids in specific linkages are essential. Although many biochemical and cell culture experiments have implicated gangliosides as MuPyV receptions, the role of gangliosides in the MuPyV-infected mouse has not been investigated. Here we report results of studies using ganglioside-deficient mice and derived cell lines. Knockout mice lacking complex gangliosides were completely resistant to the cytolytic and pathogenic effects of the virus. Embryo fibroblasts from these mice were likewise resistant to infection, and supplementation with specific gangliosides restored infectibility. Although lacking receptors for viral infection, cells from ganglioside-deficient mice retained the ability to respond to the virus. Ganglioside-deficient fibroblasts responded rapidly to virus exposure with a transient induction of c-fos as an early manifestation of a mitogenic response. Additionally, splenocytes from ganglioside-deficient mice responded to MuPyV by secretion of IL-12, previously recognized as a key mediator of the innate immune response. Thus, while gangliosides are essential for infection in the animal, gangliosides are not required for mitogenic responses and innate immune responses to the virus. Biological and structural studies have combined to give a detailed understanding of how the mouse polyomavirus binds to sialyloligosaccharides, how polymorphisms in the sialic acid binding pocket of the major virus capsid protein constitute important determinants of pathogenicity, and how gangliosides function as receptors for cell entry and infection by the virus. We used mice with knockouts in defined ganglioside biosynthetic pathways to determine whether gangliosides alone suffice to mediate lethal infection in the intact host and whether non-gangliosides are also recognized by the virus and utilized for important physiological responses. We confirmed the requirement of specific gangliosides for infection and determined that not all gangliosides that bind in vitro serve as receptors in vivo. Results also revealed two physiologically important responses that do not require MuPyV-ganglioside interactions: i) rapid induction of c-fos in fibroblasts as an early step in cell cycle progression on which the virus depends for its own replication, and ii). activation of cytokine secretion by antigen presenting cells as a critical innate immune response to the virus. We infer that these responses are mediated by non-ganglioside receptors bearing sialic acid. These results serve to illustrate the multiplicity of MuPyV receptors and the complexity of virus-cell surface interactions.
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Affiliation(s)
- John You
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Samantha D. O’Hara
- BioFrontiers Institute and the Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, United States of America
| | - Palanivel Velupillai
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Sherry Castle
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire, United States of America
| | - Steven Levery
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire, United States of America
| | - Robert L. Garcea
- BioFrontiers Institute and the Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, United States of America
- * E-mail:
| | - Thomas Benjamin
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
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15
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Napier RJ, Norris BA, Swimm A, Giver CR, Harris WAC, Laval J, Napier BA, Patel G, Crump R, Peng Z, Bornmann W, Pulendran B, Buller RM, Weiss DS, Tirouvanziam R, Waller EK, Kalman D. Low doses of imatinib induce myelopoiesis and enhance host anti-microbial immunity. PLoS Pathog 2015; 11:e1004770. [PMID: 25822986 PMCID: PMC4379053 DOI: 10.1371/journal.ppat.1004770] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 02/27/2015] [Indexed: 01/10/2023] Open
Abstract
Imatinib mesylate (Gleevec) inhibits Abl1, c-Kit, and related protein tyrosine kinases (PTKs) and serves as a therapeutic for chronic myelogenous leukemia and gastrointestinal stromal tumors. Imatinib also has efficacy against various pathogens, including pathogenic mycobacteria, where it decreases bacterial load in mice, albeit at doses below those used for treating cancer. We report that imatinib at such low doses unexpectedly induces differentiation of hematopoietic stem cells and progenitors in the bone marrow, augments myelopoiesis but not lymphopoiesis, and increases numbers of myeloid cells in blood and spleen. Whereas progenitor differentiation relies on partial inhibition of c-Kit by imatinib, lineage commitment depends upon inhibition of other PTKs. Thus, imatinib mimics “emergency hematopoiesis,” a physiological innate immune response to infection. Increasing neutrophil numbers by adoptive transfer sufficed to reduce mycobacterial load, and imatinib reduced bacterial load of Franciscella spp., which do not utilize imatinib-sensitive PTKs for pathogenesis. Thus, potentiation of the immune response by imatinib at low doses may facilitate clearance of diverse microbial pathogens. Host-directed therapeutics (HDTs) for infectious diseases target cellular mechanisms used by pathogens to move into, through, or out of cells. The Abl tyrosine kinase (TK) inhibitor and cancer therapeutic imatinib mesylate (Gleevec), for example, has activity against bacterial and viral pathogens via effects on pathogen entry (polyomaviruses), intracellular transit (Mycobacteria) and exit (poxviruses and filoviruses). Other HDTs target the host immune system by suppressing or activating circulating innate and adaptive cells. Here we report that imatinib at doses that are effective in clearing Mycobacterial infections but which are 10-fold lower than those used for cancer, mimics a physiological innate response to infection in the bone marrow, called the “emergency response,” in which hematopoietic stem cells and multipotent progenitors expand and differentiate into mature myeloid cells that migrate to peripheral sites. Imatinib effects occur in part via partial inhibition of c-Kit, suggesting a mechanism by which c-Kit controls the earliest stages of hematopoiesis. Mimicking a physiological antimicrobial response may make imatinib broadly useful. Accordingly, imatinib also has efficacy against infections caused by Franciscella spp., which do not use imatinib-sensitive TKs for pathogenesis. These observations identify myelopoiesis as an important target for HDTs, and provide information on how to dose imatinib for clinical use.
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Affiliation(s)
- Ruth J. Napier
- Microbiology and Molecular Genetics Graduate Program, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Brian A. Norris
- Immunology and Molecular Pathogenesis Graduate Program, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Alyson Swimm
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Cynthia R. Giver
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, United States of America
| | - Wayne A. C. Harris
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, United States of America
| | - Julie Laval
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Center for Cystic Fibrosis Research, Children’s Healthcare of Atlanta, Atlanta, Georgia, United States of America
- Institut de Génétique Moléculaire de Montpellier (IGMM), CNRS UMR5535, Université Montpellier, Montpellier, France
| | - Brooke A. Napier
- Microbiology and Molecular Genetics Graduate Program, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Gopi Patel
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Ryan Crump
- Department of Molecular Microbiology and Immunology, Saint Louis University, St. Louis, Missouri, United States of America
| | - Zhenghong Peng
- MD Anderson Cancer Center, University of Texas, Houston, Texas, United States of America
| | - William Bornmann
- MD Anderson Cancer Center, University of Texas, Houston, Texas, United States of America
| | - Bali Pulendran
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Emory Vaccine Center, Emory University, Atlanta, Georgia, United States of America
- Yerkes National Primate Research Center, Atlanta, Georgia, United States of America
| | - R. Mark Buller
- Department of Molecular Microbiology and Immunology, Saint Louis University, St. Louis, Missouri, United States of America
| | - David S. Weiss
- Emory Vaccine Center, Emory University, Atlanta, Georgia, United States of America
- Yerkes National Primate Research Center, Atlanta, Georgia, United States of America
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Rabindra Tirouvanziam
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Center for Cystic Fibrosis Research, Children’s Healthcare of Atlanta, Atlanta, Georgia, United States of America
| | - Edmund K. Waller
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University, Atlanta, Georgia, United States of America
| | - Daniel Kalman
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
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16
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Hutterer C, Wandinger SK, Wagner S, Müller R, Stamminger T, Zeitträger I, Godl K, Baumgartner R, Strobl S, Marschall M. Profiling of the kinome of cytomegalovirus-infected cells reveals the functional importance of host kinases Aurora A, ABL and AMPK. Antiviral Res 2013; 99:139-48. [PMID: 23648710 DOI: 10.1016/j.antiviral.2013.04.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 04/19/2013] [Accepted: 04/24/2013] [Indexed: 12/20/2022]
Abstract
Human cytomegalovirus infection can lead to life-threatening clinical manifestations particularly in the immunocompromised host. Current therapy options face severe limitations leading to a continued search for alternative drug candidates. Viral replication is dependent on a balanced interaction between viral and cellular proteins. Especially protein kinases are important regulators of virus-host interaction indicated by remarkable kinome alterations induced upon HCMV infection. Here we report a novel approach of kinome profiling with an outcome that suggests an important role of specific cellular protein kinases, such as AMPK, ABL2 and Aurora A. Inhibition of AMPK and ABL kinases showed a significant reduction, whereas inhibition of Aurora A kinase led to a slight activation of HCMV replication, as measured in a GFP reporter-based replication assay. Furthermore, analysis of the mode of antiviral action suggested a substantial benefit for the efficiency of viral replication at the immediate early (AMPK) or early-late (ABL) phases of HCMV gene expression. In contrast, inhibition of Aurora A kinase promoted an enhancement of viral early-late gene expression, suggesting a putative role of Aurora A signaling in host defense. Thus, the combined data provide new information on host cell kinases involved in viral replication and uncovered potential targets for future antiviral strategies.
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Affiliation(s)
- Corina Hutterer
- Institute for Clinical and Molecular Virology, University of Erlangen-Nuremberg, Erlangen, Germany.
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17
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Greuber EK, Pendergast AM. Abl family kinases regulate FcγR-mediated phagocytosis in murine macrophages. THE JOURNAL OF IMMUNOLOGY 2012; 189:5382-92. [PMID: 23100514 DOI: 10.4049/jimmunol.1200974] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Phagocytosis of Ab-coated pathogens is mediated through FcγRs, which activate intracellular signaling pathways to drive actin cytoskeletal rearrangements. Abl and Arg define a family of nonreceptor tyrosine kinases that regulate actin-dependent processes in a variety of cell types, including those important in the adaptive immune response. Using pharmacological inhibition as well as dominant negative and knockout approaches, we demonstrate a role for the Abl family kinases in phagocytosis by macrophages and define a mechanism whereby Abl kinases regulate this process. Bone marrow-derived macrophages from mice lacking Abl and Arg kinases exhibit inefficient phagocytosis of sheep erythrocytes and zymosan particles. Treatment with the Abl kinase inhibitors imatinib and GNF-2 or overexpression of kinase-inactive forms of the Abl family kinases also impairs particle internalization in murine macrophages, indicating Abl kinase activity is required for efficient phagocytosis. Further, Arg kinase is present at the phagocytic cup, and Abl family kinases are activated by FcγR engagement. The regulation of phagocytosis by Abl family kinases is mediated in part by the spleen tyrosine kinase (Syk). Loss of Abl and Arg expression or treatment with Abl inhibitors reduced Syk phosphorylation in response to FcγR ligation. The link between Abl family kinases and Syk may be direct, as purified Arg kinase phosphorylates Syk in vitro. Further, overexpression of membrane-targeted Syk in cells treated with Abl kinase inhibitors partially rescues the impairment in phagocytosis. Together, these findings reveal that Abl family kinases control the efficiency of phagocytosis in part through the regulation of Syk function.
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Affiliation(s)
- Emileigh K Greuber
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
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18
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Napier RJ, Shinnick TM, Kalman D. Back to the future: host-targeted chemotherapeutics for drug-resistant TB. Future Microbiol 2012; 7:431-5. [PMID: 22439718 DOI: 10.2217/fmb.12.19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Ruth J Napier
- Microbiology & Molecular Genetics Graduate Program, Emory University, Atlanta, GA 30322, USA
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19
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García M, Cooper A, Shi W, Bornmann W, Carrion R, Kalman D, Nabel GJ. Productive replication of Ebola virus is regulated by the c-Abl1 tyrosine kinase. Sci Transl Med 2012; 4:123ra24. [PMID: 22378924 DOI: 10.1126/scitranslmed.3003500] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ebola virus causes a fulminant infection in humans resulting in diffuse bleeding, vascular instability, hypotensive shock, and often death. Because of its high mortality and ease of transmission from human to human, Ebola virus remains a biological threat for which effective preventive and therapeutic interventions are needed. An understanding of the mechanisms of Ebola virus pathogenesis is critical for developing antiviral therapeutics. Here, we report that productive replication of Ebola virus is modulated by the c-Abl1 tyrosine kinase. Release of Ebola virus-like particles (VLPs) in a cell culture cotransfection system was inhibited by c-Abl1-specific small interfering RNA (siRNA) or by Abl-specific kinase inhibitors and required tyrosine phosphorylation of the Ebola matrix protein VP40. Expression of c-Abl1 stimulated an increase in phosphorylation of tyrosine 13 (Y(13)) of VP40, and mutation of Y(13) to alanine decreased the release of Ebola VLPs. Productive replication of the highly pathogenic Ebola virus Zaire strain was inhibited by c-Abl1-specific siRNAs or by the Abl-family inhibitor nilotinib by up to four orders of magnitude. These data indicate that c-Abl1 regulates budding or release of filoviruses through a mechanism involving phosphorylation of VP40. This step of the virus life cycle therefore may represent a target for antiviral therapy.
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Affiliation(s)
- Mayra García
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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20
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The Abl and Arg kinases mediate distinct modes of phagocytosis and are required for maximal Leishmania infection. Mol Cell Biol 2012; 32:3176-86. [PMID: 22665498 DOI: 10.1128/mcb.00086-12] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leishmania, an obligate intracellular parasite, binds several receptors to trigger engulfment by phagocytes, leading to cutaneous or visceral disease. These receptors include complement receptor 3 (CR3), used by promastigotes, and the Fc receptor (FcR), used by amastigotes. The mechanisms mediating uptake are not well understood. Here we show that Abl family kinases mediate both phagocytosis and the uptake of Leishmania amazonensis by macrophages (Ms). Imatinib, an Abl/Arg kinase inhibitor, decreases opsonized polystyrene bead phagocytosis and Leishmania uptake. Interestingly, phagocytosis of IgG-coated beads is decreased in Arg-deficient Ms, while that of C3bi-coated beads is unaffected. Conversely, uptake of C3bi-coated beads is decreased in Abl-deficient Ms, but that of IgG-coated beads is unaffected. Consistent with these results, Abl-deficient Ms are inefficient at C3bi-opsonized promastigote uptake, and Arg-deficient Ms are defective in IgG1-opsonized amastigote uptake. Finally, genetic loss of Abl or Arg reduces infection severity in murine cutaneous leishmaniasis, and imatinib treatment results in smaller lesions with fewer parasites than in controls. Our studies are the first to demonstrate that efficient phagocytosis and maximal Leishmania infection require Abl family kinases. These results highlight Abl family kinase-mediated signaling pathways as potential therapeutic targets for leishmaniasis.
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21
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Abstract
Human polyomaviruses are associated with substantial morbidity in immunocompromised patients, including those with HIV/AIDS, recipients of bone marrow and kidney transplants, and individuals receiving immunomodulatory agents for autoimmune and inflammatory diseases. No effective antipolyomavirus agents are currently available, and no host determinants have been identified to predict susceptibility to polyomavirus-associated diseases. Using the mouse polyomavirus (MPyV) infection model, we recently demonstrated that perforin-granzyme exocytosis, tumor necrosis factor alpha (TNF-α), and Fas did not contribute to control of infection or virus-induced tumors. Gamma interferon (IFN-γ) was recently shown to inhibit replication by human BK polyomavirus in primary cultures of renal tubular epithelial cells. In this study, we provide evidence that IFN-γ is an important component of the host defense against MPyV infection and tumorigenesis. In immortalized and primary cells, IFN-γ reduces expression of MPyV proteins and impairs viral replication. Mice deficient for the IFN-γ receptor (IFN-γR(-/-)) maintain higher viral loads during MPyV infection and are susceptible to MPyV-induced tumors; this increased viral load is not associated with a defective MPyV-specific CD8(+) T cell response. Using an acute MPyV infection kidney transplant model, we further show that IFN-γR(-/-) donor kidneys harbor higher MPyV levels than donor kidneys from wild-type mice. Finally, administration of IFN-γ to persistently infected mice significantly reduces MPyV levels in multiple organs, including the kidney, a major reservoir for persistent mouse and human polyomavirus infections. These findings demonstrate that IFN-γ is an antiviral effector molecule for MPyV infection.
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22
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Wessler S, Backert S. Abl family of tyrosine kinases and microbial pathogenesis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 286:271-300. [PMID: 21199784 DOI: 10.1016/b978-0-12-385859-7.00006-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Abl nonreceptor tyrosine kinases are activated by multiple stimuli and regulate cytoskeletal reorganization, cell proliferation, survival, and stress responses. Several downstream pathways have direct impact on physiological processes, including development and maintenance of the nervous and immune systems and epithelial morphogenesis. Recent studies also indicated that numerous viral and bacterial pathogens highjack Abl signaling for different purposes. Abl kinases are activated to reorganize the host actin cytoskeleton and promote the direct tyrosine phosphorylation of viral surface proteins and injected bacterial type-III and type-IV effector molecules. However, Abl kinases also play other roles in infectious processes of bacteria, viruses, and prions. These activities have crucial impact on microbial invasion and release from host cells, actin-based motility, pedestal formation, as well as cell-cell dissociation involved in epithelial barrier disruption and other responses. Thus, Abl kinases exhibit important functions in pathological signaling during microbial infections. Here, we discuss the different signaling pathways activated by pathogens and highlight possible therapeutic intervention strategies.
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Affiliation(s)
- Silja Wessler
- Department of Molecular Biology, Division of Microbiology, Paris-Lodron University of Salzburg, Billrothstrasse, Salzburg, Austria
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23
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Randhawa PS, Farasati NA, Huang Y, Mapara MY, Shapiro R. Viral drug sensitivity testing using quantitative PCR: effect of tyrosine kinase inhibitors on polyomavirus BK replication. Am J Clin Pathol 2010; 134:916-20. [PMID: 21088155 DOI: 10.1309/ajcp7jyhjn1pgqvc] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Our objective was to determine whether quantitative polymerase chain reaction (PCR) can be used to measure the effect of tyrosine kinase (TK) inhibition on polyomavirus BK (BKV) replication. The BKV was grown in a cell culture system. The rate of viral replication in the presence or absence of the drug being tested was assessed by amplifying the viral genome using primers directed against the viral capsid 1 protein. Dasatinib, erlotinib, gefitinib, imatinib, sunitinib, and sorafenib all showed antiviral activity at micromolar concentrations. The 50% effective concentration for erlotinib and sorafenib was within blood concentrations readily achieved in human subjects. Quantitative PCR is a convenient method for viral drug sensitivity testing for slow-growing viruses that do not readily produce cytopathic effect. TK inhibitors deserve further consideration as a potential therapeutic option for BKV-associated nephropathy and hemorrhagic cystitis.
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