1
|
Petkidis A, Andriasyan V, Murer L, Volle R, Greber UF. A versatile automated pipeline for quantifying virus infectivity by label-free light microscopy and artificial intelligence. Nat Commun 2024; 15:5112. [PMID: 38879641 PMCID: PMC11180103 DOI: 10.1038/s41467-024-49444-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 06/03/2024] [Indexed: 06/19/2024] Open
Abstract
Virus infectivity is traditionally determined by endpoint titration in cell cultures, and requires complex processing steps and human annotation. Here we developed an artificial intelligence (AI)-powered automated framework for ready detection of virus-induced cytopathic effect (DVICE). DVICE uses the convolutional neural network EfficientNet-B0 and transmitted light microscopy images of infected cell cultures, including coronavirus, influenza virus, rhinovirus, herpes simplex virus, vaccinia virus, and adenovirus. DVICE robustly measures virus-induced cytopathic effects (CPE), as shown by class activation mapping. Leave-one-out cross-validation in different cell types demonstrates high accuracy for different viruses, including SARS-CoV-2 in human saliva. Strikingly, DVICE exhibits virus class specificity, as shown with adenovirus, herpesvirus, rhinovirus, vaccinia virus, and SARS-CoV-2. In sum, DVICE provides unbiased infectivity scores of infectious agents causing CPE, and can be adapted to laboratory diagnostics, drug screening, serum neutralization or clinical samples.
Collapse
Affiliation(s)
- Anthony Petkidis
- Department of Molecular Life Sciences, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
- Life Science Zurich Graduate School, ETH and University of Zürich, 8057, Zurich, Switzerland
| | - Vardan Andriasyan
- Department of Molecular Life Sciences, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Luca Murer
- Department of Molecular Life Sciences, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
- Roche Diagnostics, Forrenstrasse 2, 6343, Rotkreuz, Switzerland
| | - Romain Volle
- Department of Molecular Life Sciences, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland.
| |
Collapse
|
2
|
Lucifora J, Alfaiate D, Pons C, Michelet M, Ramirez R, Fusil F, Amirache F, Rossi A, Legrand AF, Charles E, Vegna S, Farhat R, Rivoire M, Passot G, Gadot N, Testoni B, Bach C, Baumert TF, Hyrina A, Beran RK, Zoulim F, Boonstra A, Büning H, Verrier ER, Cosset FL, Fletcher SP, Salvetti A, Durantel D. Hepatitis D virus interferes with hepatitis B virus RNA production via interferon-dependent and -independent mechanisms. J Hepatol 2023; 78:958-970. [PMID: 36702177 DOI: 10.1016/j.jhep.2023.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 01/10/2023] [Accepted: 01/10/2023] [Indexed: 01/25/2023]
Abstract
BACKGROUND & AIMS Chronic coinfection with HBV and HDV leads to the most aggressive form of chronic viral hepatitis. Herein, we aimed to elucidate the molecular mechanisms underlying the widely reported observation that HDV interferes with HBV in most coinfected patients. METHODS Patient liver tissues, primary human hepatocytes, HepaRG cells and human liver chimeric mice were used to analyze the effect of HDV on HBV using virological and RNA-sequencing analyses, as well as RNA synthesis, stability and association assays. RESULTS Transcriptomic analyses in cell culture and mouse models of coinfection enabled us to define an HDV-induced signature, mainly composed of interferon (IFN)-stimulated genes (ISGs). We also provide evidence that ISGs are upregulated in chronically HDV/HBV-coinfected patients but not in cells that only express HDV antigen (HDAg). Inhibition of the hepatocyte IFN response partially rescued the levels of HBV parameters. We observed less HBV RNA synthesis upon HDV infection or HDV protein expression. Additionally, HDV infection or expression of HDAg alone specifically accelerated the decay of HBV RNA, and HDAg was associated with HBV RNAs. On the contrary, HDAg expression did not affect other viruses such as HCV or SARS-CoV-2. CONCLUSIONS Our data indicate that HDV interferes with HBV through both IFN-dependent and IFN-independent mechanisms. Specifically, we uncover a new viral interference mechanism in which proteins of a satellite virus affect the RNA production of its helper virus. Exploiting these findings could pave the way to the development of new therapeutic strategies against HBV. IMPACT AND IMPLICATIONS Although the molecular mechanisms remained unexplored, it has long been known that despite its dependency, HDV decreases HBV viremia in patients. Herein, using in vitro and in vivo models, we showed that HDV interferes with HBV through both IFN-dependent and IFN-independent mechanisms affecting HBV RNA metabolism, and we defined the HDV-induced modulation signature. The mechanisms we uncovered could pave the way for the development of new therapeutic strategies against HBV by mimicking and/or increasing the effect of HDAg on HBV RNA. Additionally, the HDV-induced modulation signature could potentially be correlated with responsiveness to IFN-α treatment, thereby helping to guide management of HBV/HDV-coinfected patients.
Collapse
Affiliation(s)
- Julie Lucifora
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France; INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France.
| | - Dulce Alfaiate
- INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France; Service des Maladies Infectieuses et Tropicales, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
| | - Caroline Pons
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France; INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - Maud Michelet
- INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | | | - Floriane Fusil
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
| | - Fouzia Amirache
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
| | - Axel Rossi
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany
| | - Anne-Flore Legrand
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
| | - Emilie Charles
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
| | - Serena Vegna
- INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - Rayan Farhat
- INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | | | - Guillaume Passot
- Service de chirurgie générale et Oncologique, Hôpital Lyon Sud, Hospices Civils de Lyon Et CICLY, EA3738, Université Lyon 1, France
| | - Nicolas Gadot
- INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - Barbara Testoni
- INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - Charlotte Bach
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMR_S1110, Strasbourg, France
| | - Thomas F Baumert
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMR_S1110, Strasbourg, France; Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, 67000 Strasbourg, France
| | | | | | - Fabien Zoulim
- INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France; Department of Hepatology, Croix-Rousse Hospital, Hospices Civils de Lyon, Lyon, France
| | - Andre Boonstra
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center Rotterdam, Gravendijkwal 230, Rotterdam, the Netherlands
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany
| | - Eloi R Verrier
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMR_S1110, Strasbourg, France
| | - François-Loïc Cosset
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
| | | | - Anna Salvetti
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France; INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| | - David Durantel
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France; INSERM, U1052, Cancer Research Center of Lyon (CRCL), University of Lyon (UCBL1), CNRS UMR_5286, Centre Léon Bérard, Lyon, France
| |
Collapse
|
3
|
Andriasyan V, Yakimovich A, Petkidis A, Georgi F, Witte R, Puntener D, Greber UF. Microscopy deep learning predicts virus infections and reveals mechanics of lytic-infected cells. iScience 2021; 24:102543. [PMID: 34151222 PMCID: PMC8192562 DOI: 10.1016/j.isci.2021.102543] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 01/07/2021] [Accepted: 05/12/2021] [Indexed: 02/07/2023] Open
Abstract
Imaging across scales reveals disease mechanisms in organisms, tissues, and cells. Yet, particular infection phenotypes, such as virus-induced cell lysis, have remained difficult to study. Here, we developed imaging modalities and deep learning procedures to identify herpesvirus and adenovirus (AdV) infected cells without virus-specific stainings. Fluorescence microscopy of vital DNA-dyes and live-cell imaging revealed learnable virus-specific nuclear patterns transferable to related viruses of the same family. Deep learning predicted two major AdV infection outcomes, non-lytic (nonspreading) and lytic (spreading) infections, up to about 20 hr prior to cell lysis. Using these predictive algorithms, lytic and non-lytic nuclei had the same levels of green fluorescent protein (GFP)-tagged virion proteins but lytic nuclei enriched the virion proteins faster, and collapsed more extensively upon laser-rupture than non-lytic nuclei, revealing impaired mechanical properties of lytic nuclei. Our algorithms may be used to infer infection phenotypes of emerging viruses, enhance single cell biology, and facilitate differential diagnosis of non-lytic and lytic infections. Artificial intelligence identifies HSV- and AdV-infected cells without specific probes. Imaging lytic-infected cells reveals nuclear envelope rupture and AdV dissemination. Live cell imaging and neural networks presciently pinpoint lytic-infected cells. Lytic-infected cell nuclei have mechanical properties distinct from non-lytic nuclei.
Collapse
Affiliation(s)
- Vardan Andriasyan
- Department of Molecular Life Sciences, University of Zürich, Zürich 8057, Switzerland
| | - Artur Yakimovich
- Department of Molecular Life Sciences, University of Zürich, Zürich 8057, Switzerland.,University College London, London WC1E 6BT, UK.,Artificial Intelligence for Life Sciences CIC, London N8 7FJ, UK
| | - Anthony Petkidis
- Department of Molecular Life Sciences, University of Zürich, Zürich 8057, Switzerland
| | - Fanny Georgi
- Department of Molecular Life Sciences, University of Zürich, Zürich 8057, Switzerland
| | - Robert Witte
- Department of Molecular Life Sciences, University of Zürich, Zürich 8057, Switzerland
| | - Daniel Puntener
- Department of Molecular Life Sciences, University of Zürich, Zürich 8057, Switzerland.,Roche Diagnostics International Ltd, Rotkreuz 6343, Switzerland
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zürich, Zürich 8057, Switzerland
| |
Collapse
|
4
|
The HSV-1 Transcription Factor ICP4 Confers Liquid-Like Properties to Viral Replication Compartments. Int J Mol Sci 2021; 22:ijms22094447. [PMID: 33923223 PMCID: PMC8123221 DOI: 10.3390/ijms22094447] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/18/2021] [Accepted: 04/22/2021] [Indexed: 12/25/2022] Open
Abstract
Herpes Simplex Virus Type-1 (HSV-1) forms progeny in the nucleus within distinct membrane-less inclusions, the viral replication compartments (VRCs), where viral gene expression, DNA replication, and packaging occur. The way in which the VRCs maintain spatial integrity remains unresolved. Here, we demonstrate that the essential viral transcription factor ICP4 is an intrinsically disordered protein (IDP) capable of driving protein condensation and liquid–liquid phase separation (LLPS) in transfected cells. Particularly, ICP4 forms nuclear liquid-like condensates in a dose- and time-dependent manner. Fluorescence recovery after photobleaching (FRAP) assays revealed rapid exchange rates of EYFP-ICP4 between phase-separated condensates and the surroundings, akin to other viral IDPs that drive LLPS. Likewise, HSV-1 VRCs revealed by EYFP-tagged ICP4 retained their liquid-like nature, suggesting that they are phase-separated condensates. Individual VRCs homotypically fused when reaching close proximity and grew over the course of infection. Together, the results of this study demonstrate that the HSV-1 transcription factor ICP4 has characteristics of a viral IDP, forms condensates in the cell nucleus by LLPS, and can be used as a proxy for HSV-1 VRCs with characteristics of liquid–liquid phase-separated condensates.
Collapse
|
5
|
Bauer M, Flatt JW, Seiler D, Cardel B, Emmenlauer M, Boucke K, Suomalainen M, Hemmi S, Greber UF. The E3 Ubiquitin Ligase Mind Bomb 1 Controls Adenovirus Genome Release at the Nuclear Pore Complex. Cell Rep 2020; 29:3785-3795.e8. [PMID: 31851912 DOI: 10.1016/j.celrep.2019.11.064] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/15/2019] [Accepted: 11/14/2019] [Indexed: 01/06/2023] Open
Abstract
Adenoviruses (AdVs) cause respiratory, ocular, and gastrointestinal tract infection and inflammation in immunocompetent people and life-threatening disease upon immunosuppression. AdV vectors are widely used in gene therapy and vaccination. Incoming particles attach to nuclear pore complexes (NPCs) of post-mitotic cells, then rupture and deliver viral DNA (vDNA) to the nucleus or misdeliver to the cytosol. Our genome-wide RNAi screen in AdV-infected cells identified the RING-type E3 ubiquitin ligase Mind bomb 1 (Mib1) as a proviral host factor for AdV infection. Mib1 is implicated in Notch-Delta signaling, ciliary biogenesis, and RNA innate immunity. Mib1 depletion arrested incoming AdVs at NPCs. Induced expression of full-length but not ligase-defective Mib1 in knockout cells triggered vDNA uncoating from NPC-tethered virions, nuclear import, misdelivery of vDNA, and vDNA expression. Mib1 is an essential host factor for AdV uncoating in human cells, and it provides a new concept for licensing virion DNA delivery through the NPC.
Collapse
Affiliation(s)
- Michael Bauer
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland; Life Science Zurich Graduate School, ETH and University of Zurich, 8057 Zurich, Switzerland
| | - Justin W Flatt
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland; Institute of Biotechnology, University of Helsinki, 00790 Helsinki, Finland; Department of Biosciences, University of Helsinki, 00790 Helsinki, Finland
| | - Daria Seiler
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland
| | - Bettina Cardel
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland
| | | | - Karin Boucke
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland
| | - Maarit Suomalainen
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland
| | - Silvio Hemmi
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland.
| |
Collapse
|
6
|
Georgi F, Andriasyan V, Witte R, Murer L, Hemmi S, Yu L, Grove M, Meili N, Kuttler F, Yakimovich A, Turcatti G, Greber UF. The FDA-Approved Drug Nelfinavir Inhibits Lytic Cell-Free but Not Cell-Associated Nonlytic Transmission of Human Adenovirus. Antimicrob Agents Chemother 2020; 64:e01002-20. [PMID: 32601166 PMCID: PMC7449217 DOI: 10.1128/aac.01002-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 06/19/2020] [Indexed: 02/07/2023] Open
Abstract
Adenoviruses (AdVs) are prevalent and give rise to chronic and recurrent disease. Human AdV (HAdV) species B and C, such as HAdV-C2, -C5, and -B14, cause respiratory disease and constitute a health threat for immunocompromised individuals. HAdV-Cs are well known for lysing cells owing to the E3 CR1-β-encoded adenovirus death protein (ADP). We previously reported a high-throughput image-based screening framework and identified an inhibitor of HAdV-C2 multiround infection, nelfinavir mesylate. Nelfinavir is the active ingredient of Viracept, an FDA-approved inhibitor of human immunodeficiency virus (HIV) aspartyl protease that is used to treat AIDS. It is not effective against single-round HAdV infections. Here, we show that nelfinavir inhibits lytic cell-free transmission of HAdV, indicated by the suppression of comet-shaped infection foci in cell culture. Comet-shaped foci occur upon convection-based transmission of cell-free viral particles from an infected cell to neighboring uninfected cells. HAdV lacking ADP was insensitive to nelfinavir but gave rise to comet-shaped foci, indicating that ADP enhances but is not required for cell lysis. This was supported by the notion that HAdV-B14 and -B14p1 lacking ADP were highly sensitive to nelfinavir, although HAdV-A31, -B3, -B7, -B11, -B16, -B21, -D8, -D30, and -D37 were less sensitive. Conspicuously, nelfinavir uncovered slow-growing round HAdV-C2 foci, independent of neutralizing antibodies in the medium, indicative of nonlytic cell-to-cell transmission. Our study demonstrates the repurposing potential of nelfinavir with postexposure efficacy against different HAdVs and describes an alternative nonlytic cell-to-cell transmission mode of HAdV.
Collapse
Affiliation(s)
- Fanny Georgi
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Vardan Andriasyan
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Robert Witte
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Luca Murer
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Silvio Hemmi
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Lisa Yu
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Melanie Grove
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Nicole Meili
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Fabien Kuttler
- Biomolecular Screening Facility, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Artur Yakimovich
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- Artificial Intelligence for Life Sciences CIC, London, United Kingdom
| | - Gerardo Turcatti
- Biomolecular Screening Facility, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| |
Collapse
|
7
|
Meier AF, Fraefel C, Seyffert M. The Interplay between Adeno-Associated Virus and its Helper Viruses. Viruses 2020; 12:E662. [PMID: 32575422 PMCID: PMC7354565 DOI: 10.3390/v12060662] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/15/2020] [Accepted: 06/18/2020] [Indexed: 12/14/2022] Open
Abstract
The adeno-associated virus (AAV) is a small, nonpathogenic parvovirus, which depends on helper factors to replicate. Those helper factors can be provided by coinfecting helper viruses such as adenoviruses, herpesviruses, or papillomaviruses. We review the basic biology of AAV and its most-studied helper viruses, adenovirus type 5 (AdV5) and herpes simplex virus type 1 (HSV-1). We further outline the direct and indirect interactions of AAV with those and additional helper viruses.
Collapse
Affiliation(s)
| | | | - Michael Seyffert
- Institute of Virology, University of Zurich, CH-8057 Zurich, Switzerland; (A.F.M.); (C.F.)
| |
Collapse
|
8
|
Abstract
This study introduces label-free digital holo-tomographic microscopy (DHTM) and refractive index gradient (RIG) measurements of live, virus-infected cells. We use DHTM to describe virus type-specific cytopathic effects, including cyclic volume changes of vaccinia virus infections, and cytoplasmic condensations in herpesvirus and rhinovirus infections, distinct from apoptotic cells. This work shows for the first time that DHTM is suitable to observe virus-infected cells and distinguishes virus type-specific signatures under noninvasive conditions. It provides a basis for future studies, where correlative fluorescence microscopy of cell and virus structures annotate distinct RIG values derived from DHTM. Cytopathic effects (CPEs) are a hallmark of infections. CPEs are difficult to observe due to phototoxicity from classical light microscopy. We report distinct patterns of virus infections in live cells using digital holo-tomographic microscopy (DHTM). DHTM is label-free and records the phase shift of low-energy light passing through the specimen on a transparent surface with minimal perturbation. DHTM measures the refractive index (RI) and computes the refractive index gradient (RIG), unveiling optical heterogeneity in cells. We find that vaccinia virus (VACV), herpes simplex virus (HSV), and rhinovirus (RV) infections progressively and distinctly increased RIG. VACV infection, but not HSV and RV infections, induced oscillations of cell volume, while all three viruses altered cytoplasmic membrane dynamics and induced apoptotic features akin to those caused by the chemical compound staurosporine. In sum, we introduce DHTM for quantitative label-free microscopy in infection research and uncover virus type-specific changes and CPE in living cells with minimal interference. IMPORTANCE This study introduces label-free digital holo-tomographic microscopy (DHTM) and refractive index gradient (RIG) measurements of live, virus-infected cells. We use DHTM to describe virus type-specific cytopathic effects, including cyclic volume changes of vaccinia virus infections, and cytoplasmic condensations in herpesvirus and rhinovirus infections, distinct from apoptotic cells. This work shows for the first time that DHTM is suitable to observe virus-infected cells and distinguishes virus type-specific signatures under noninvasive conditions. It provides a basis for future studies, where correlative fluorescence microscopy of cell and virus structures annotate distinct RIG values derived from DHTM.
Collapse
|
9
|
MxB is an interferon-induced restriction factor of human herpesviruses. Nat Commun 2018; 9:1980. [PMID: 29773792 PMCID: PMC5958057 DOI: 10.1038/s41467-018-04379-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 04/19/2018] [Indexed: 12/12/2022] Open
Abstract
The type I interferon (IFN) system plays an important role in controlling herpesvirus infections, but it is unclear which IFN-mediated effectors interfere with herpesvirus replication. Here we report that human myxovirus resistance protein B (MxB, also designated Mx2) is a potent human herpesvirus restriction factor in the context of IFN. We demonstrate that ectopic MxB expression restricts a range of herpesviruses from the Alphaherpesvirinae and Gammaherpesvirinae, including herpes simplex virus 1 and 2 (HSV-1 and HSV-2), and Kaposi’s sarcoma-associated herpesvirus (KSHV). MxB restriction of HSV-1 and HSV-2 requires GTPase function, in contrast to restriction of lentiviruses. MxB inhibits the delivery of incoming HSV-1 DNA to the nucleus and the appearance of empty capsids, but not the capsid delivery to the cytoplasm or tegument dissociation from the capsid. Our study identifies MxB as a potent pan-herpesvirus restriction factor which blocks the uncoating of viral DNA from the incoming viral capsid. MxB is an interferon-induced GTPase that inhibits HIV replication. Here, Crameri et al. show that MxB restricts replication of herpesviruses by inhibiting delivery of incoming viral DNA into the nucleus, and this antiviral activity depends on MxB’s GTPase activity.
Collapse
|
10
|
Cell Cycle-Dependent Expression of Adeno-Associated Virus 2 (AAV2) Rep in Coinfections with Herpes Simplex Virus 1 (HSV-1) Gives Rise to a Mosaic of Cells Replicating either AAV2 or HSV-1. J Virol 2017; 91:JVI.00357-17. [PMID: 28515305 DOI: 10.1128/jvi.00357-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 05/05/2017] [Indexed: 12/19/2022] Open
Abstract
Adeno-associated virus 2 (AAV2) depends on the simultaneous presence of a helper virus such as herpes simplex virus 1 (HSV-1) for productive replication. At the same time, AAV2 efficiently blocks the replication of HSV-1, which would eventually limit its own replication by diminishing the helper virus reservoir. This discrepancy begs the question of how AAV2 and HSV-1 can coexist in a cell population. Here we show that in coinfected cultures, AAV2 DNA replication takes place almost exclusively in S/G2-phase cells, while HSV-1 DNA replication is restricted to G1 phase. Live microscopy revealed that not only wild-type AAV2 (wtAAV2) replication but also reporter gene expression from both single-stranded and double-stranded (self-complementary) recombinant AAV2 vectors preferentially occurs in S/G2-phase cells, suggesting that the preference for S/G2 phase is independent of the nature of the viral genome. Interestingly, however, a substantial proportion of S/G2-phase cells transduced by the double-stranded but not the single-stranded recombinant AAV2 vectors progressed through mitosis in the absence of the helper virus. We conclude that cell cycle-dependent AAV2 rep expression facilitates cell cycle-dependent AAV2 DNA replication and inhibits HSV-1 DNA replication. This may limit competition for cellular and viral helper factors and, hence, creates a biological niche for either virus to replicate.IMPORTANCE Adeno-associated virus 2 (AAV2) differs from most other viruses, as it requires not only a host cell for replication but also a helper virus such as an adenovirus or a herpesvirus. This situation inevitably leads to competition for cellular resources. AAV2 has been shown to efficiently inhibit the replication of helper viruses. Here we present a new facet of the interaction between AAV2 and one of its helper viruses, herpes simplex virus 1 (HSV-1). We observed that AAV2 rep gene expression is cell cycle dependent and gives rise to distinct time-controlled windows for HSV-1 replication. High Rep protein levels in S/G2 phase support AAV2 replication and inhibit HSV-1 replication. Conversely, low Rep protein levels in G1 phase permit HSV-1 replication but are insufficient for AAV2 replication. This allows both viruses to productively replicate in distinct sets of dividing cells.
Collapse
|
11
|
Seyffert M, Glauser DL, Schraner EM, de Oliveira AP, Mansilla-Soto J, Vogt B, Büning H, Linden RM, Ackermann M, Fraefel C. Novel Mutant AAV2 Rep Proteins Support AAV2 Replication without Blocking HSV-1 Helpervirus Replication. PLoS One 2017; 12:e0170908. [PMID: 28125695 PMCID: PMC5268427 DOI: 10.1371/journal.pone.0170908] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 01/12/2017] [Indexed: 11/19/2022] Open
Abstract
As their names imply, parvoviruses of the genus Dependovirus rely for their efficient replication on the concurrent presence of a helpervirus, such as herpesvirus, adenovirus, or papilloma virus. Adeno-associated virus 2 (AAV2) is such an example, which in turn can efficiently inhibit the replication of each helpervirus by distinct mechanisms. In a previous study we have shown that expression of the AAV2 rep gene is not compatible with efficient replication of herpes simplex virus 1 (HSV-1). In particular, the combined DNA-binding and ATPase/helicase activities of the Rep68/78 proteins have been shown to exert opposite effects on the replication of AAV2 and HSV-1. While essential for AAV2 DNA replication these protein activities account for the Rep-mediated inhibition of HSV-1 replication. Here, we describe a novel Rep mutant (Rep-D371Y), which displayed an unexpected phenotype. Rep-D371Y did not block HSV-1 replication, but still supported efficient AAV2 replication, at least when a double-stranded AAV2 genome template was used. We also found that the capacity of Rep-D371Y to induce apoptosis and a Rep-specific DNA damage response was significantly reduced compared to wild-type Rep. These findings suggest that AAV2 Rep-helicase subdomains exert diverging activities, which contribute to distinct steps of the AAV2 life cycle. More important, the novel AAV2 mutant Rep-D371Y may allow deciphering yet unsolved activities of the AAV2 Rep proteins such as DNA second-strand synthesis, genomic integration or packaging, which all involve the Rep-helicase activity.
Collapse
Affiliation(s)
- Michael Seyffert
- Institute of Virology, University of Zurich, Zurich, Switzerland
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | | | - Elisabeth M. Schraner
- Institute of Virology, University of Zurich, Zurich, Switzerland
- Institute of Veterinary Anatomy, University of Zurich, Zurich, Switzerland
| | | | - Jorge Mansilla-Soto
- Center for Cell Engineering, Memorial Sloan Kettering Cancer Center, New York, New York, United States of America
| | - Bernd Vogt
- Institute of Virology, University of Zurich, Zurich, Switzerland
| | - Hildegard Büning
- Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
- Institute for Experimental Hematology, Hannover Medical School, Hannover, Germany
| | - R. Michael Linden
- Department of Infectious Diseases, King’s College London, London, United Kingdom
| | | | - Cornel Fraefel
- Institute of Virology, University of Zurich, Zurich, Switzerland
- * E-mail:
| |
Collapse
|
12
|
A Regulatory Element Near the 3' End of the Adeno-Associated Virus rep Gene Inhibits Adenovirus Replication in cis by Means of p40 Promoter-Associated Short Transcripts. J Virol 2016; 90:3981-93. [PMID: 26842470 DOI: 10.1128/jvi.03120-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 01/26/2016] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED Adeno-associated virus (AAV) has long been known to inhibit helper adenovirus (Ad) replication independently of AAV Rep protein expression. More recently, replication of Ad serotype 5 (Ad5)/AAV serotype 2 (AAV-2) hybrid vectors was shown to be inhibited incisby a sequence near the 3' end of AAVrep, termed the Rep inhibition sequence for adenoviral replication (RIS-Ad). RIS-Ad functions independently of Rep protein expression. Here we demonstrate that inhibition of adenoviral replication by RIS-Ad requires an active AAV p40 promoter and the 5' half of the intron. In addition, Ad inhibition is critically dependent on the integrity of the p40 transcription start site (TSS) leading to short p40-associated transcripts. These do not give rise to effector molecules capable of inhibiting adenoviral replication intrans, like small polypeptides or microRNAs. Our data point to an inhibitory mechanism in which RNA polymerase II (Pol II) pauses directly downstream of the p40 promoter, leading to interference of the stalled Pol II transcription complex with the adenoviral replication machinery. Whereas inhibition by RIS-Ad is mediated exclusively incis, it can be overcome by providing a replication-competent adenoviral genome intrans Moreover, the inhibitory effect of RIS-Ad is not limited to AAV-2 but could also be shown for the corresponding regions of other AAV serotypes, including AAV-5. These findings have important implications for the future generation of Ad5/AAV hybrid vectors. IMPORTANCE Insertion of sequences from the 3' part of therepgene of adeno-associated virus (AAV) into the genome of its helper adenovirus strongly reduces adenoviral genome replication. We could show that this inhibition is mediated exclusively inciswithout the involvement oftrans-acting regulatory RNAs or polypeptides but nevertheless requires an active AAV-2 p40 promoter and p40-associated short transcripts. Our results suggest a novel inhibitory mechanism that has so far not been described for AAV and that involves stalled RNA polymerase II complexes and their interference with adenoviral DNA replication. Such a mechanism would have important implications both for the generation of adenoviral vectors expressing the AAVrepandcapgenes and for the regulation of AAV gene expression in the absence and presence of helper virus.
Collapse
|
13
|
Super-resolution imaging of nuclear import of adeno-associated virus in live cells. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2015; 2:15047. [PMID: 26665132 PMCID: PMC4667716 DOI: 10.1038/mtm.2015.47] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 10/12/2015] [Accepted: 10/26/2015] [Indexed: 01/18/2023]
Abstract
Adeno-associated virus (AAV) has been developed as a promising human gene therapy vector. Particularly, recombinant AAV vector (rAAV) achieves its transduction of host cells by crossing at least three physiological barriers including plasma membrane, endosomal membrane, and nuclear envelope (NE). So far, the AAV transduction mechanism has not been explored thoroughly at the single viral particle level. In this study, we employed high-speed super-resolution single-point edge-excitation sub-diffraction (SPEED) microscopy to map the events of single rAAV2 particles infecting live human cells with an unprecedented spatiotemporal resolution of 9–12 nm and 2–20 ms. Data reveal that rAAV2 particles are imported through nuclear pore complexes (NPCs) rather than nuclear membrane budding into the nucleus. Moreover, approximately 17% of the rAAV2 molecules starting from the cytoplasm successfully transverse the NPCs to reach the nucleoplasm, revealing that the NPCs act as a strict selective step for AAV delivery. This study lastly suggests a new pathway to improve AAV vectors for human gene therapy.
Collapse
|
14
|
Adeno-Associated Virus Type 2 Rep68 Can Bind to Consensus Rep-Binding Sites on the Herpes Simplex Virus 1 Genome. J Virol 2015; 89:11150-8. [PMID: 26292324 DOI: 10.1128/jvi.01370-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 08/11/2015] [Indexed: 01/10/2023] Open
Abstract
Adeno-associated virus type 2 is known to inhibit replication of herpes simplex virus 1 (HSV-1). This activity has been linked to the helicase- and DNA-binding domains of the Rep68/Rep78 proteins. Here, we show that Rep68 can bind to consensus Rep-binding sites on the HSV-1 genome and that the Rep helicase activity can inhibit replication of any DNA if binding is facilitated. Therefore, we hypothesize that inhibition of HSV-1 replication involves direct binding of Rep68/Rep78 to the HSV-1 genome.
Collapse
|
15
|
Adeno-associated virus type 2 modulates the host DNA damage response induced by herpes simplex virus 1 during coinfection. J Virol 2011; 86:143-55. [PMID: 22013059 DOI: 10.1128/jvi.05694-11] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Adeno-associated virus type 2 (AAV2) is a human parvovirus that relies on a helper virus for efficient replication. Herpes simplex virus 1 (HSV-1) supplies helper functions and changes the environment of the cell to promote AAV2 replication. In this study, we examined the accumulation of cellular replication and repair proteins at viral replication compartments (RCs) and the influence of replicating AAV2 on HSV-1-induced DNA damage responses (DDR). We observed that the ATM kinase was activated in cells coinfected with AAV2 and HSV-1. We also found that phosphorylated ATR kinase and its cofactor ATR-interacting protein were recruited into AAV2 RCs, but ATR signaling was not activated. DNA-PKcs, another main kinase in the DDR, was degraded during HSV-1 infection in an ICP0-dependent manner, and this degradation was markedly delayed during AAV2 coinfection. Furthermore, we detected phosphorylation of DNA-PKcs during AAV2 but not HSV-1 replication. The AAV2-mediated delay in DNA-PKcs degradation affected signaling through downstream substrates. Overall, our results demonstrate that coinfection with HSV-1 and AAV2 provokes a cellular DDR which is distinct from that induced by HSV-1 alone.
Collapse
|
16
|
Glauser DL, Fraefel C. Interactions between AAV-2 and HSV-1: implications for hybrid vector design. Future Virol 2011. [DOI: 10.2217/fvl.11.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herpes simplex virus type 1 (HSV-1)-based amplicon vectors have a transgene capacity of up to 150 kbp and can efficiently transduce many different cell types in culture and in vivo without causing cytopathic effects. However, these vectors do not support long-term transgene expression. Adeno-associated virus type 2 (AAV-2) has the capacity to integrate its genome into a specific site on human chromosome 19, but AAV-2-derived gene therapy vectors have a transgene capacity of only 4.5 kb. To combine the large transgene capacity of HSV-1 with the potential for site-specific genomic integration and long-term transgene expression of AAV-2, HSV/AAV hybrid vectors have been developed. This review describes the design, applications and limitations of these hybrid vectors. However, as HSV-1 is a full helper virus for AAV-2 replication, the main focus is the analysis of the molecular mechanisms of interaction between the two viruses. The knowledge of these interactions will have direct implications on the design of novel HSV/AAV hybrid vectors.
Collapse
Affiliation(s)
- Daniel L Glauser
- Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Cornel Fraefel
- Institute of Virology, University of Zurich, Winterthurerstr. 266a, 8057 Zurich, Switzerland
| |
Collapse
|