1
|
Munz CM, Kreher H, Erdbeer A, Richter S, Westphal D, Yi B, Behrendt R, Stanke N, Lindel F, Lindemann D. Efficient production of inhibitor-free foamy virus glycoprotein-containing retroviral vectors by proteoglycan-deficient packaging cells. Mol Ther Methods Clin Dev 2022; 26:394-412. [PMID: 36034773 PMCID: PMC9388887 DOI: 10.1016/j.omtm.2022.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 07/07/2022] [Indexed: 11/21/2022]
Abstract
Foamy viruses (FVs) or heterologous retroviruses pseudotyped with FV glycoprotein enable transduction of a great variety of target tissues of disparate species. Specific cellular entry receptors responsible for this exceptionally broad tropism await their identification. Though, ubiquitously expressed heparan sulfate proteoglycan (HS-PG) is known to serve as an attachment factor of FV envelope (Env)-containing virus particles, greatly enhancing target cell permissiveness. Production of high-titer, FV Env-containing retroviral vectors is strongly dependent on the use of cationic polymer-based transfection reagents like polyethyleneimine (PEI). We identified packaging cell-surface HS-PG expression to be responsible for this requirement. Efficient release of FV Env-containing virus particles necessitates neutralization of HS-PG binding sites by PEI. Remarkably, remnants of PEI in FV Env-containing vector supernatants, which are not easily removable, negatively impact target cell transduction, in particular those of myeloid and lymphoid origin. To overcome this limitation for production of FV Env-containing retrovirus supernatants, we generated 293T-based packaging cell lines devoid of HS-PG by genome engineering. This enabled, for the first, time production of inhibitor-free, high-titer FV Env-containing virus supernatants by non-cationic polymer-mediated transfection. Depending on the type of virus, produced titers were 2- to 10-fold higher compared with those obtained by PEI transfection.
Collapse
Affiliation(s)
- Clara Marie Munz
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Henriette Kreher
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Alexander Erdbeer
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Stefanie Richter
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany
| | - Dana Westphal
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Buqing Yi
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Rayk Behrendt
- Institute of Immunology, Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, 01307 Dresden, Germany
| | - Nicole Stanke
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany
| | - Fabian Lindel
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
- Corresponding author Fabian Lindel,Cell line Screening & Development (CLSD), Novartis Institutes for BioMedical Research (NIBR), WSJ-360, Kohlenstrasse, 4056 Basel, Switzerland.
| | - Dirk Lindemann
- Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany
- Corresponding author Dirk Lindemann, Institute of Medical Microbiology and Virology, University Hospital and Medical Faculty “Carl Gustav Carus”, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany.
| |
Collapse
|
2
|
The Unique, the Known, and the Unknown of Spumaretrovirus Assembly. Viruses 2021; 13:v13010105. [PMID: 33451128 PMCID: PMC7828637 DOI: 10.3390/v13010105] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/08/2021] [Accepted: 01/10/2021] [Indexed: 12/22/2022] Open
Abstract
Within the family of Retroviridae, foamy viruses (FVs) are unique and unconventional with respect to many aspects in their molecular biology, including assembly and release of enveloped viral particles. Both components of the minimal assembly and release machinery, Gag and Env, display significant differences in their molecular structures and functions compared to the other retroviruses. This led to the placement of FVs into a separate subfamily, the Spumaretrovirinae. Here, we describe the molecular differences in FV Gag and Env, as well as Pol, which is translated as a separate protein and not in an orthoretroviral manner as a Gag-Pol fusion protein. This feature further complicates FV assembly since a specialized Pol encapsidation strategy via a tripartite Gag-genome–Pol complex is used. We try to relate the different features and specific interaction patterns of the FV Gag, Pol, and Env proteins in order to develop a comprehensive and dynamic picture of particle assembly and release, but also other features that are indirectly affected. Since FVs are at the root of the retrovirus tree, we aim at dissecting the unique/specialized features from those shared among the Spuma- and Orthoretrovirinae. Such analyses may shed light on the evolution and characteristics of virus envelopment since related viruses within the Ortervirales, for instance LTR retrotransposons, are characterized by different levels of envelopment, thus affecting the capacity for intercellular transmission.
Collapse
|
3
|
Simian Foamy Viruses in Central and South America: A New World of Discovery. Viruses 2019; 11:v11100967. [PMID: 31635161 PMCID: PMC6832937 DOI: 10.3390/v11100967] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 12/16/2022] Open
Abstract
Foamy viruses (FVs) are the only exogenous retrovirus to date known to infect neotropical primates (NPs). In the last decade, an increasing number of strains have been completely or partially sequenced, and molecular evolution analyses have identified an ancient co-speciation with their hosts. In this review, the improvement of diagnostic techniques that allowed the determination of a more accurate prevalence of simian FVs (SFVs) in captive and free-living NPs is discussed. Determination of DNA viral load in American primates indicates that oral tissues are the viral replicative site and that buccal swab collection can be an alternative to diagnose SFV infection in NPs. Finally, the transmission potential of NP SFVs to primate workers in zoos and primate centers of the Americas is examined.
Collapse
|
4
|
Souto S, Olveira JG, García-Rosado E, Dopazo CP, Bandín I. Amino acid changes in the capsid protein of a reassortant betanodavirus strain: Effect on viral replication in vitro and in vivo. JOURNAL OF FISH DISEASES 2019; 42:221-227. [PMID: 30511462 DOI: 10.1111/jfd.12916] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 10/01/2018] [Accepted: 10/04/2018] [Indexed: 06/09/2023]
Abstract
Betanodavirus reassortant strains (RGNNV/SJNNV) isolated from Senegalese sole harbour an SJNNV capsid featuring several changes with respect to the SJNNV-type strain, sharing three hallmark substitutions. Here, we have employed recombinant strains harbouring mutations in these positions (r20 and r20 + 247 + 270) and have demonstrated that the three substitutions affect different steps of the viral replication process. Adsorption ability and efficiency of viral attachment were only affected by substitutions in the C-terminal side of the capsid. However, the concurrent mutation in the N-terminal side seems to slightly decrease these properties, suggesting that this region could also be involved in viral binding. Differences in the intracellular and extracellular production of the mutant strains suggest that both the C-terminal and N-terminal regions of the capsid protein may be involved in the particle budding. Furthermore, viral replication in sole brain tissue of the mutant strains, and especially double- and triple-mutant strains, is clearly delayed with respect to the wt strain. These data support previous findings indicating that the C-terminal side plays a role in virulence because of a slower spread in the fish host brain and suggest that the concurrent participation of the N-terminal side is also important for viral replication in vivo.
Collapse
Affiliation(s)
- Sandra Souto
- Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - José G Olveira
- Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Esther García-Rosado
- Facultad de Ciencias, Departamento de Microbiología, Universidad de Málaga, Málaga, Spain
| | - Carlos P Dopazo
- Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Isabel Bandín
- Departamento de Microbiología y Parasitología, Instituto de Acuicultura, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| |
Collapse
|
5
|
Wei G, Kehl T, Bao Q, Benner A, Lei J, Löchelt M. The chromatin binding domain, including the QPQRYG motif, of feline foamy virus Gag is required for viral DNA integration and nuclear accumulation of Gag and the viral genome. Virology 2018; 524:56-68. [PMID: 30145377 DOI: 10.1016/j.virol.2018.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 08/08/2018] [Accepted: 08/08/2018] [Indexed: 01/15/2023]
Abstract
The retroviral Gag protein, the major component of released particles, plays different roles in particle assembly, maturation or infection of new host cells. Here, we characterize the Gag chromatin binding site including the highly conserved QPQRYG motif of feline foamy virus, a member of the Spumaretrovirinae. Mutagenesis of critical residues in the chromatin binding site/QPQRYG motif almost completely abrogates viral DNA integration and reduces nuclear accumulation of Gag and viral DNA. Genome packaging, reverse transcription, particle release and uptake into new target cells are not affected. The integrity of the QPQRYG motif appears to be important for processes after cytosolic entry, likely influencing incoming virus capsids or disassembly intermediates but not Gag synthesized de novo in progeny virus-producing cells. According to our data, chromatin binding is a shared feature among foamy viruses but further work is needed to understand the mechanisms involved.
Collapse
Affiliation(s)
- Guochao Wei
- Division of Molecular Diagnostics of Oncogenic Infections, Research Focus Infection, Inflammation and Cancer, German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), Heidelberg, Germany
| | - Timo Kehl
- Division of Molecular Diagnostics of Oncogenic Infections, Research Focus Infection, Inflammation and Cancer, German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), Heidelberg, Germany
| | - Qiuying Bao
- Division of Molecular Diagnostics of Oncogenic Infections, Research Focus Infection, Inflammation and Cancer, German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), Heidelberg, Germany
| | - Axel Benner
- Division of Biostatistics, German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), Heidelberg, Germany
| | - Janet Lei
- Division of Molecular Diagnostics of Oncogenic Infections, Research Focus Infection, Inflammation and Cancer, German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), Heidelberg, Germany
| | - Martin Löchelt
- Division of Molecular Diagnostics of Oncogenic Infections, Research Focus Infection, Inflammation and Cancer, German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), Heidelberg, Germany.
| |
Collapse
|