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Mancino M, Lai G, De Grossi F, Cuomo A, Manganaro L, Butta GM, Ferrari I, Vicenzi E, Poli G, Pesce E, Oliveto S, Biffo S, Manfrini N. FAM46C Is an Interferon-Stimulated Gene That Inhibits Lentiviral Particle Production by Modulating Autophagy. Microbiol Spectr 2023; 11:e0521122. [PMID: 37358411 PMCID: PMC10434054 DOI: 10.1128/spectrum.05211-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 06/02/2023] [Indexed: 06/27/2023] Open
Abstract
FAM46C is a multiple myeloma (MM) tumor suppressor whose function is only starting to be elucidated. We recently showed that in MM cells FAM46C triggers apoptosis by inhibiting autophagy and altering intracellular trafficking and protein secretion. To date, both a physiological characterization of FAM46C role and an assessment of FAM46C-induced phenotypes outside of MM are lacking. Preliminary reports suggested an involvement of FAM46C with regulation of viral replication, but this was never confirmed. Here, we show that FAM46C is an interferon-stimulated gene and that the expression of wild-type FAM46C in HEK-293T cells, but not of its most frequently found mutant variants, inhibits the production of both HIV-1-derived and HIV-1 lentiviruses. We demonstrate that this effect does not require transcriptional regulation and does not depend on inhibition of either global or virus-specific translation but rather mostly relies on FAM46C-induced deregulation of autophagy, a pathway that we show to be required for efficient lentiviral particle production. These studies not only provide new insights on the physiological role of the FAM46C protein but also could help in implementing more efficient antiviral strategies on one side and lentiviral particle production approaches on the other. IMPORTANCE FAM46C role has been thoroughly investigated in MM, but studies characterizing its role outside of the tumoral environment are still lacking. Despite the success of antiretroviral therapy in suppressing HIV load to undetectable levels, there is currently no HIV cure, and treatment is lifelong. Indeed, HIV continues to be a major global public health issue. Here, we show that FAM46C expression in HEK-293T cells inhibits the production of both HIV and HIV-derived lentiviruses. We also demonstrate that such inhibitory effect relies, at least in part, on the well-established regulatory role that FAM46C exerts on autophagy. Deciphering the molecular mechanism underlying this regulation will not only facilitate the understanding of FAM46C physiological role but also give new insights on the interplay between HIV and the cellular environment.
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Affiliation(s)
- Marilena Mancino
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | - Giancarlo Lai
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | | | - Alessandro Cuomo
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Lara Manganaro
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Giacomo M. Butta
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Ivan Ferrari
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | - Elisa Vicenzi
- Viral Pathogenesis and Biosafety Unit, San Raffaele Scientific Institute, Milan, Italy
| | - Guido Poli
- Viral Pathogenesis and Biosafety Unit, San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute San Raffaele University School of Medicine, Milan, Italy
| | - Elisa Pesce
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | - Stefania Oliveto
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
- Department of Biosciences, University of Milan, Milan, Italy
| | - Stefano Biffo
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
- Department of Biosciences, University of Milan, Milan, Italy
| | - Nicola Manfrini
- INGM, Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
- Department of Biosciences, University of Milan, Milan, Italy
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Cabrera-Rodríguez R, Pérez-Yanes S, Lorenzo-Sánchez I, Estévez-Herrera J, García-Luis J, Trujillo-González R, Valenzuela-Fernández A. TDP-43 Controls HIV-1 Viral Production and Virus Infectiveness. Int J Mol Sci 2023; 24:ijms24087658. [PMID: 37108826 PMCID: PMC10142003 DOI: 10.3390/ijms24087658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/16/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
The transactive response DNA-binding protein (TARDBP/TDP-43) is known to stabilize the anti-HIV-1 factor, histone deacetylase 6 (HDAC6). TDP-43 has been reported to determine cell permissivity to HIV-1 fusion and infection acting on tubulin-deacetylase HDAC6. Here, we studied the functional involvement of TDP-43 in the late stages of the HIV-1 viral cycle. The overexpression of TDP-43, in virus-producing cells, stabilized HDAC6 (i.e., mRNA and protein) and triggered the autophagic clearance of HIV-1 Pr55Gag and Vif proteins. These events inhibited viral particle production and impaired virion infectiveness, observing a reduction in the amount of Pr55Gag and Vif proteins incorporated into virions. A nuclear localization signal (NLS)-TDP-43 mutant was not able to control HIV-1 viral production and infection. Likewise, specific TDP-43-knockdown reduced HDAC6 expression (i.e., mRNA and protein) and increased the expression level of HIV-1 Vif and Pr55Gag proteins and α-tubulin acetylation. Thus, TDP-43 silencing favored virion production and enhanced virus infectious capacity, thereby increasing the amount of Vif and Pr55Gag proteins incorporated into virions. Noteworthy, there was a direct relationship between the content of Vif and Pr55Gag proteins in virions and their infection capacity. Therefore, for TDP-43, the TDP-43/HDAC6 axis could be considered a key factor to control HIV-1 viral production and virus infectiveness.
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Affiliation(s)
- Romina Cabrera-Rodríguez
- Laboratorio "Inmunología Celular y Viral", Unidad de Farmacología, Sección de Medicina, Facultad de Ciencias de la Salud, Universidad de La Laguna (ULL), 38320 La Laguna, Tenerife, Spain
| | - Silvia Pérez-Yanes
- Laboratorio "Inmunología Celular y Viral", Unidad de Farmacología, Sección de Medicina, Facultad de Ciencias de la Salud, Universidad de La Laguna (ULL), 38320 La Laguna, Tenerife, Spain
| | - Iria Lorenzo-Sánchez
- Laboratorio "Inmunología Celular y Viral", Unidad de Farmacología, Sección de Medicina, Facultad de Ciencias de la Salud, Universidad de La Laguna (ULL), 38320 La Laguna, Tenerife, Spain
| | - Judith Estévez-Herrera
- Laboratorio "Inmunología Celular y Viral", Unidad de Farmacología, Sección de Medicina, Facultad de Ciencias de la Salud, Universidad de La Laguna (ULL), 38320 La Laguna, Tenerife, Spain
| | - Jonay García-Luis
- Laboratorio "Inmunología Celular y Viral", Unidad de Farmacología, Sección de Medicina, Facultad de Ciencias de la Salud, Universidad de La Laguna (ULL), 38320 La Laguna, Tenerife, Spain
| | - Rodrigo Trujillo-González
- Laboratorio "Inmunología Celular y Viral", Unidad de Farmacología, Sección de Medicina, Facultad de Ciencias de la Salud, Universidad de La Laguna (ULL), 38320 La Laguna, Tenerife, Spain
- Analysis Department, Faculty of Mathematics, Universidad de La Laguna (ULL), 38296 La Laguna, Tenerife, Spain
| | - Agustín Valenzuela-Fernández
- Laboratorio "Inmunología Celular y Viral", Unidad de Farmacología, Sección de Medicina, Facultad de Ciencias de la Salud, Universidad de La Laguna (ULL), 38320 La Laguna, Tenerife, Spain
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Pradeep Ram AS, Mauduit ME, Colombet J, Perriere F, Thouvenot A, Sime-Ngando T. Top-Down Controls of Bacterial Metabolism: A Case Study from a Temperate Freshwater Lake Ecosystem. Microorganisms 2022; 10. [PMID: 35456766 DOI: 10.3390/microorganisms10040715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/23/2022] [Accepted: 03/25/2022] [Indexed: 12/10/2022] Open
Abstract
In freshwater environments, limited data exist on the impact of mortality forces (viruses and heterotrophic nanoflagellates) on bacterial growth efficiency (BGE, index of bacterial carbon metabolism) compared to resource availability. An investigation to determine the relative influence of viral lysis and flagellate predation (top-down forces) on BGE was conducted in a mesotrophic freshwater system (Lake Goule, France) with time and space. Viral abundance was significantly (p < 0.001) related to bacterial abundance by a power law function with an exponent less than 1, emphasizing that the increases in host population (bacteria) together with viruses were not proportionate. A lytic viral strategy was evident throughout the study period, with high lysis of the bacterial population (up to 60%) supported by viral production rates. Viral processes (lysis and production) that were influenced by bacterial production and heterotrophic nanoflagellate abundance had a positive impact on BGE. Estimates of BGE were variable (9.9−45.5%) due to uncoupling between two metabolic parameters—namely bacterial production and respiration. The existence of a synergistic relationship between viruses and flagellates with bacteria in Lake Goule highlighted the decisive impact of top-down agents in sustaining the bacterial carbon metabolism of non-infected population through the nature of vital resources released via mortality processes.
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Yu J, Zhang W, Huo W, Meng X, Zhong T, Su Y, Liu Y, Liu J, Wang Z, Song F, Zhang S, Li Z, Yu X, Yu X, Hua S. Regulation of host factor γ-H2AX level and location by enterovirus A71 for viral replication. Virulence 2022; 13:241-257. [PMID: 35067196 PMCID: PMC8786350 DOI: 10.1080/21505594.2022.2028482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Numerous viruses manipulate host factors for viral production. We demonstrated that human enterovirus A71 (EVA71), a primary causative agent for hand, foot, and mouth disease (HFMD), increased the level of the DNA damage response (DDR) marker γ-H2AX. DDR is primarily mediated by the ataxia telangiectasia mutated (ATM), ATM and Rad3-related (ATR), or DNA-dependent protein kinase (DNA-PK) pathways. Upregulation of γ-H2AX by EVA71 was dependent on the ATR but not the ATM or DNA-PK pathway. As a nuclear factor, there is no previous evidence of cytoplasmic distribution of γ-H2AX. However, the present findings demonstrated that EVA71 encouraged the localization of γ-H2AX to the cytoplasm. Of note, γ-H2AX formed a complex with structural protein VP3, non-structural protein 3D, and the viral genome. Treatment with an inhibitor or CRISPR/Cas9 technology to decrease or silence the expression of γ-H2AX decreased viral genome replication in host cells; this effect was accompanied by decreased viral protein expression and virions. In animal experiments, caffeine was used to inhibit DDR; the results revealed that caffeine protected neonatal mice from death after infection with EVA71, laying the foundation for new therapeutic applications of caffeine. More importantly, in children with HFMD, γ-H2AX was upregulated in peripheral blood lymphocytes. The consistent in vitro and in vivo data on γ-H2AX from this study suggested that caffeine or other inhibitors of DDR might be novel therapeutic agents for HFMD.
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Affiliation(s)
- Jinghua Yu
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Wenyan Zhang
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Wenbo Huo
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Xiangling Meng
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Ting Zhong
- Medicinal Chemistry, College of Pharmacy, Changchun University of Chinese Medicine, Changchun, China
| | - Ying Su
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Yumeng Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Jinming Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Zengyan Wang
- Department of Internal Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Fengmei Song
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Shuxia Zhang
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Zhaolong Li
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Xiaoyan Yu
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Xiaofang Yu
- Institute of Virology and AIDS Research, the First Hospital of Jilin University, Jilin University, Changchun, China
| | - Shucheng Hua
- Department of Internal Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China
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Yang Y, Nagata T. Viral Production in Seawater Filtered Through 0.2-μm Pore-Size Filters: A Hidden Biogeochemical Cycle in a Neglected Realm. Front Microbiol 2021; 12:774849. [PMID: 34867916 PMCID: PMC8637275 DOI: 10.3389/fmicb.2021.774849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/25/2021] [Indexed: 11/20/2022] Open
Abstract
Viral production is a key parameter for assessing virus-mediated biogeochemical cycles. One widely used method for the determination of viral production, called the virus reduction assay, reduces viral abundance, while maintaining bacterial abundance, using 0.2-μm pore-size filters. Viral production is estimated from the increase of viral abundance during incubation. We hypothesized that small-cell-sized bacterial communities can pass through 0.2-μm filters and drive viral production, representing a missing fraction of viral production that is missed by the virus reduction assay. Coastal seawater was filtered through 0.2-μm filters and diluted with virus-free seawater. Viral production in the <0.2-μm filtrate was estimated from changes in viral abundance determined through flow cytometry. We found that viruses were produced in the <0.2-μm communities, which were strongly enriched with low nucleic acid content bacteria. Estimated viral production in the <0.2-μm filtrates accounted for up to 43% of total viral production and 10% of dissolved organic carbon production mediated by viral lysis of bacterial cells. By not considering viral production in these <0.2-μm communities, the virus reduction assay may underestimate viral production. Virus–bacteria interactions in <0.2-μm communities may represent a significant and overlooked role of viruses in marine food webs and carbon fluxes.
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Affiliation(s)
- Yanhui Yang
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan
| | - Toshi Nagata
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan
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Brendle S, Li JJ, Cladel NM, Shearer DA, Budgeon LR, Balogh KK, Atkins H, Costa-Fujishima M, Lopez P, Christensen ND, Doorbar J, Murooka TT, Hu J. Mouse Papillomavirus L1 and L2 Are Dispensable for Viral Infection and Persistence at Both Cutaneous and Mucosal Tissues. Viruses 2021; 13:1824. [PMID: 34578405 PMCID: PMC8473024 DOI: 10.3390/v13091824] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/08/2021] [Accepted: 09/10/2021] [Indexed: 01/07/2023] Open
Abstract
Papillomavirus L1 and L2, the major and minor capsid proteins, play significant roles in viral assembly, entry, and propagation. In the current study, we investigate the impact of L1 and L2 on viral life cycle and tumor growth with a newly established mouse papillomavirus (MmuPV1) infection model. MmuPV1 L1 knockout, L2 knockout, and L1 plus L2 knockout mutant genomes (designated as L1ATGko-4m, L2ATGko, and L1-L2ATGko respectively) were generated. The mutants were examined for their ability to generate lesions in athymic nude mice. Viral activities were examined by qPCR, immunohistochemistry (IHC), in situ hybridization (ISH), and transmission electron microscopy (TEM) analyses. We demonstrated that viral DNA replication and tumor growth occurred at both cutaneous and mucosal sites infected with each of the mutants. Infections involving L1ATGko-4m, L2ATGko, and L1-L2ATGko mutant genomes generally resulted in smaller tumor sizes compared to infection with the wild type. The L1 protein was absent in L1ATGko-4m and L1-L2ATGko mutant-treated tissues, even though viral transcripts and E4 protein expression were robust. Therefore, L1 is not essential for MmuPV1-induced tumor growth, and this finding parallels our previous observations in the rabbit papillomavirus model. Very few viral particles were detected in L2ATGko mutant-infected tissues. Interestingly, the localization of L1 in lesions induced by L2ATGko was primarily cytoplasmic rather than nuclear. The findings support the hypothesis that the L2 gene influences the expression, location, transport, and assembly of the L1 protein in vivo.
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Affiliation(s)
- Sarah Brendle
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Jingwei J. Li
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Nancy M. Cladel
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Debra A. Shearer
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Lynn R. Budgeon
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Karla K. Balogh
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Hannah Atkins
- Laboratory Medicine, Department of Pathology, Division of Comparative Medicine, University of North Carolina, Chapel Hill, NC 27599, USA;
| | - Marina Costa-Fujishima
- Department of Immunology, University of Manitoba, Winnipeg, MB R3E 0T5, Canada; (M.C.-F.); (P.L.); (T.T.M.)
| | - Paul Lopez
- Department of Immunology, University of Manitoba, Winnipeg, MB R3E 0T5, Canada; (M.C.-F.); (P.L.); (T.T.M.)
| | - Neil D. Christensen
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
- Department of Microbiology and Immunology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - John Doorbar
- Department of Pathology, Division of Virology, University of Cambridge, Tennis Court Road, Cambridge CB21 QP, UK;
| | - Thomas T. Murooka
- Department of Immunology, University of Manitoba, Winnipeg, MB R3E 0T5, Canada; (M.C.-F.); (P.L.); (T.T.M.)
| | - Jiafen Hu
- The Jake Gittlen Laboratories for Cancer Research, Hershey, PA 17033, USA; (S.B.); (J.J.L.); (N.M.C.); (D.A.S.); (L.R.B.); (K.K.B.); (N.D.C.)
- Department of Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
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Abdulrahman Ashy R, Suttle CA, Agustí S. Moderate Seasonal Dynamics Indicate an Important Role for Lysogeny in the Red Sea. Microorganisms 2021; 9:1269. [PMID: 34207938 DOI: 10.3390/microorganisms9061269] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/08/2021] [Accepted: 05/13/2021] [Indexed: 11/17/2022] Open
Abstract
Viruses are the most abundant microorganisms in marine environments and viral infections can be either lytic (virulent) or lysogenic (temperate phage) within the host cell. The aim of this study was to quantify viral dynamics (abundance and infection) in the coastal Red Sea, a narrow oligotrophic basin with high surface water temperatures (22–32 °C degrees), high salinity (37.5–41) and continuous high insolation, thus making it a stable and relatively unexplored environment. We quantified viral and environmental changes in the Red Sea (two years) and the occurrence of lysogenic bacteria (induced by mitomycin C) on the second year. Water temperatures ranged from 24.0 to 32.5 °C, and total viral and bacterial abundances ranged from 1.5 to 8.7 × 106 viruses mL−1 and 1.9 to 3.2 × 105 bacteria mL−1, respectively. On average, 12.24% ± 4.8 (SE) of the prophage bacteria could be induced by mitomycin C, with the highest percentage of 55.8% observed in January 2018 when bacterial abundances were low; whereas no induction was measurable in spring when bacterial abundances were highest. Thus, despite the fact that the Red Sea might be perceived as stable, warm and saline, relatively modest changes in seasonal conditions were associated with large swings in the prevalence of lysogeny.
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López-Vázquez C, Bandín I, Panzarin V, Toffan A, Cuenca A, Olesen NJ, Dopazo CP. Steps of the Replication Cycle of the Viral Haemorrhagic Septicaemia Virus (VHSV) Affecting Its Virulence on Fish. Animals (Basel) 2020; 10:E2264. [PMID: 33271890 PMCID: PMC7761041 DOI: 10.3390/ani10122264] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/26/2020] [Accepted: 11/26/2020] [Indexed: 12/14/2022] Open
Abstract
The viral haemorrhagic septicaemia virus (VHSV), a single-stranded negative-sense RNA novirhabdovirus affecting a wide range of marine and freshwater fish species, is a main concern for European rainbow trout (Oncorhynchus mykiss) fish farmers. Its genome is constituted by six genes, codifying five structural and one nonstructural proteins. Many studies have been carried out to determine the participation of each gene in the VHSV virulence, most of them based on genome sequence analysis and/or reverse genetics to construct specific mutants and to evaluate their virulence phenotype. In the present study, we have used a different approach with a similar aim: hypothesizing that a failure in any step of the replication cycle can reduce the virulence in vivo, we studied in depth the in vitro replication of VHSV in different cell lines, using sets of strains from different origins, with high, low and moderate levels of virulence for fish. The results demonstrated that several steps in the viral replication cycle could affect VHSV virulence in fish, including adsorption, RNA synthesis and morphogenesis (including viral release). Notably, differences among strains in any step of the replication cycle were mostly strain-specific and reflected only in part the in vivo phenotype (high and low virulent). Our data, therefore, support the need for further studies aimed to construct completely avirulent VHSV recombinants targeting a combination of genes rather than a single one in order to study the mechanisms of genes interplay and their effect on viral phenotype in vitro and in vivo.
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Affiliation(s)
- Carmen López-Vázquez
- Instituto de Acuicultura-Dpt Microbiología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain; (C.L.-V.); (I.B.)
| | - Isabel Bandín
- Instituto de Acuicultura-Dpt Microbiología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain; (C.L.-V.); (I.B.)
| | - Valentina Panzarin
- Department of Comparative Biomedical Sciences, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell’Università 10, 35020 Legnaro, Padova, Italy; (V.P.); (A.T.)
| | - Anna Toffan
- Department of Comparative Biomedical Sciences, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell’Università 10, 35020 Legnaro, Padova, Italy; (V.P.); (A.T.)
| | - Argelia Cuenca
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, Technical University of Denmark, Kemitorvet 202, 2800 Kgs Lyngby, Denmark; (A.C.); (N.J.O.)
| | - Niels J. Olesen
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, Technical University of Denmark, Kemitorvet 202, 2800 Kgs Lyngby, Denmark; (A.C.); (N.J.O.)
| | - Carlos P. Dopazo
- Instituto de Acuicultura-Dpt Microbiología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain; (C.L.-V.); (I.B.)
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Huo W, Yu J, Liu C, Wu T, Wang Y, Meng X, Song F, Zhang S, Su Y, Liu Y, Liu J, Yu X, Hua S. Caspase-3 inhibitor inhibits enterovirus D68 production. J Microbiol 2020; 58:812-820. [PMID: 32870487 PMCID: PMC7459088 DOI: 10.1007/s12275-020-0241-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/19/2020] [Accepted: 06/22/2020] [Indexed: 12/20/2022]
Abstract
Enterovirus D68 (EVD68) is an emerging pathogen that recently caused a large worldwide outbreak of severe respiratory disease in children. However, the relationship between EVD68 and host cells remains unclear. Caspases are involved in cell death, immune response, and even viral production. We found that caspase-3 was activated during EVD68 replication to induce apoptosis. Caspase-3 inhibitor (Z-DEVD-FMK) inhibited viral production, protected host cells from the cytopathic effects of EVD68 infection, and prevented EVD68 from regulating the host cell cycle at G0/G1. Meanwhile, caspase-3 activator (PAC-1) increased EVD68 production. EVD68 infection therefore activates caspase-3 for virus production. This knowledge provides a potential direction for the prevention and treatment of disease related to EVD68.
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Affiliation(s)
- Wenbo Huo
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, 130000, P. R. China.,Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Jinghua Yu
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, 130000, P. R. China
| | - Chunyu Liu
- Acupuncture Department, The Affiliated Hospital of Changchun University of Chinese Medicine, Changchun, 130000, P. R. China
| | - Ting Wu
- Neonatal Intensive Care Unit, The First Hospital of Jilin University, Jilin University, Changchun, 130000, P. R. China
| | - Yue Wang
- Department of Chemistry of Traditional Chinese Medicine, Changchun University of Chinese Medicine, Changchun, 130000, P. R. China
| | - Xiangling Meng
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Fengmei Song
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Shuxia Zhang
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Ying Su
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Yumeng Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Jinming Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Xiaoyan Yu
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changhun, 130000, P. R. China
| | - Shucheng Hua
- Department of Internal Medicine, The First Hospital of Jilin University, Jilin University, Changchun, 130000, P. R. China.
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10
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Abdulrahman Ashy R, Agustí S. Low Host Abundance and High Temperature Determine Switching from Lytic to Lysogenic Cycles in Planktonic Microbial Communities in a Tropical Sea (Red Sea). Viruses 2020; 12:v12070761. [PMID: 32679656 PMCID: PMC7411798 DOI: 10.3390/v12070761] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/15/2020] [Accepted: 06/17/2020] [Indexed: 12/26/2022] Open
Abstract
The lytic and lysogenic life cycles of marine phages are influenced by environmental conditions such as solar radiation, temperature, and host abundance. Temperature can regulate phage infection, but its role is difficult to discern in oligotrophic waters where there is typically low host abundance and high temperatures. Here, we study the temporal variability of viral dynamics and the occurrence of lysogeny using mitomycin C in a eutrophic coastal lagoon in the oligotrophic Red Sea, which showed strong seasonality in terms of temperature (22.1–33.3 °C) and large phytoplankton blooms. Viral abundances ranged from 2.2 × 106 to 1.5 × 107 viruses mL−1 and were closely related to chlorophyll a (chl a) concentration. Observed high virus-to-bacterium ratio (VBR) (4–79; 16 ± 4 (SE)) suggests that phages exerted a tight control of their hosts as indicated by the significant decrease in bacterial abundance with increasing virus concentration. Heterotrophic bacterial abundance also showed a significant decrease with increasing temperature. However, viral abundance was not related to temperature changes and the interaction of water temperature, suggesting an indirect effect of temperature on decreased host abundance, which was observed at the end of the summertime. From the estimated burst size (BS), we observed lysogeny (undetectable to 29.1%) at low percentages of 5.0% ± 1.2 (SE) in half of the incubations with mitomycin C, while it increased to 23.9% ± 2.8 (SE) when the host abundance decreased. The results suggest that lytic phages predominate, switching to a moderate proportion of temperate phages when the host abundance reduces.
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Affiliation(s)
- Ruba Abdulrahman Ashy
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
- Department of Biological Sciences, Faculty of Science, University of Jeddah, Jeddah 23445, Saudi Arabia
- Correspondence: or (R.A.A.); (S.A.)
| | - Susana Agustí
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
- Correspondence: or (R.A.A.); (S.A.)
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11
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Zhang S, Yu X, Meng X, Huo W, Su Y, Liu J, Liu Y, Zhang J, Wang S, Yu J. Coxsackievirus A6 Induces Necroptosis for Viral Production. Front Microbiol 2020; 11:42. [PMID: 32117097 PMCID: PMC7011610 DOI: 10.3389/fmicb.2020.00042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 01/09/2020] [Indexed: 12/13/2022] Open
Abstract
Hand, foot, and mouth disease (HFMD) is a febrile exanthematous disease with typical or atypical symptoms. Typical HFMD is usually caused by enterovirus 71 (EV71) or coxsackievirus A16, while atypical HFMD is usually caused by coxsackievirus A6 (CA6). In recent years, worldwide outbreaks of CA6-associated HFMD have dramatically increased, although the pathogenic mechanism of CA6 is still unclear. EV71 has been established to induce caspase-dependent apoptosis, but in this study, we demonstrate that CA6 infection promotes a distinct pathway of cell death that involves loss of cell membrane integrity. Necrostatin-1, an inhibitor of necroptosis, blocks the cell death induced by CA6 infection, but Z-DEVD-FMK, an inhibitor of caspase-3, has no effect on CA6-induced cell death. Furthermore, CA6 infection up-regulates the expression of the necroptosis signaling molecule RIPK3. Importantly, necrostatin-1 inhibits CA6 viral production, as assessed by its ability to inhibit levels of VP1 protein and genomic RNA and infectious particles. CA6-induced necroptosis is not dependent on the generation of reactive oxygen species; however, viral 3D protein can directly bind RIPK3, which is suggestive of a direct mechanism of necroptosis induction. Therefore, these results indicate that CA6 induces a mechanism of RIPK3-dependent necroptosis for viral production that is distinct from the mechanism of apoptosis induced by typical HFMD viruses.
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Affiliation(s)
- Shuxia Zhang
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changchun, China
| | - Xiaoyan Yu
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changchun, China
| | - Xiangling Meng
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changchun, China
| | - Wenbo Huo
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changchun, China
| | - Ying Su
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changchun, China
| | - Jinming Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changchun, China
| | - Yumeng Liu
- Department of Experimental Pharmacology and Toxicology, School of Pharmaceutical Science, Jilin University, Changchun, China
| | - Jun Zhang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Shaohua Wang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Jinghua Yu
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
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12
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Marrero-Hernández S, Márquez-Arce D, Cabrera-Rodríguez R, Estévez-Herrera J, Pérez-Yanes S, Barroso-González J, Madrid R, Machado JD, Blanco J, Valenzuela-Fernández A. HIV-1 Nef Targets HDAC6 to Assure Viral Production and Virus Infection. Front Microbiol 2019; 10:2437. [PMID: 31736889 PMCID: PMC6831784 DOI: 10.3389/fmicb.2019.02437] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/10/2019] [Indexed: 12/11/2022] Open
Abstract
HIV Nef is a central auxiliary protein in HIV infection and pathogenesis. Our results indicate that HDAC6 promotes the aggresome/autophagic degradation of the viral polyprotein Pr55Gag to inhibit HIV-1 production. Nef counteracts this antiviral activity of HDAC6 by inducing its degradation and subsequently stabilizing Pr55Gag and Vif viral proteins. Nef appears to neutralize HDAC6 by an acidic/endosomal-lysosomal processing and does not need the downregulation function, since data obtained with the non-associated cell-surface Nef-G2A mutant - the cytoplasmic location of HDAC6 - together with studies with chemical inhibitors and other Nef mutants, point to this direction. Hence, the polyproline rich region P72xxP75 (69-77 aa) and the di-Leucin motif in the Nef-ExxxLL160-165 sequence of Nef, appear to be responsible for HDAC6 clearance and, therefore, required for this novel Nef proviral function. Nef and Nef-G2A co-immunoprecipitate with HDAC6, whereas the Nef-PPAA mutant showed a reduced interaction with the anti-HIV-1 enzyme. Thus, the P72xxP75 motif appears to be responsible, directly or indirectly, for the interaction of Nef with HDAC6. Remarkably, by neutralizing HDAC6, Nef assures Pr55Gag location and aggregation at plasma membrane, as observed by TIRFM, promotes viral egress, and enhances the infectivity of viral particles. Consequently, our results suggest that HDAC6 acts as an anti-HIV-1 restriction factor, limiting viral production and infection by targeting Pr55Gag and Vif. This function is counteracted by functional HIV-1 Nef, in order to assure viral production and infection capacities. The interplay between HIV-1 Nef and cellular HDAC6 may determine viral infection and pathogenesis, representing both molecules as key targets to battling HIV.
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Affiliation(s)
- Sara Marrero-Hernández
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Daniel Márquez-Arce
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Romina Cabrera-Rodríguez
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Judith Estévez-Herrera
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Silvia Pérez-Yanes
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Jonathan Barroso-González
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Ricardo Madrid
- BioAssays SL, Campus de Cantoblanco, Madrid, Spain.,Departmento de Genética, Fisiología y Microbiología, Facultad de Biología, Universidad Complutense de Madrid (UCM), Madrid, Spain
| | - José-David Machado
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain
| | - Julià Blanco
- AIDS Research Institute IrsiCaixa, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Badalona, Spain.,Universitat de Vic-Central de Catalunya, UVIC-UCC, Catalonia, Spain
| | - Agustín Valenzuela-Fernández
- Laboratorio de Inmunología Celular y Viral, Unidad de Farmacología, Sección de Medicina, Facultad de Medicina, Universidad de La Laguna (ULL), La Laguna, Spain.,Unidad Virología y Microbiología del IUETSPC, Universidad de La Laguna (ULL), La Laguna, Spain
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13
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Chen SH, Haam J, Walker M, Scappini E, Naughton J, Martin NP. Production of Viral Constructs for Neuroanatomy, Calcium Imaging, and Optogenetics. ACTA ACUST UNITED AC 2019; 87:e66. [PMID: 30883041 DOI: 10.1002/cpns.66] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Advances in design and use of light-sensitive and light-emitting sensors have facilitated observation, measurement, and control of neuronal activities. Viruses are effective vectors for delivery of these valuable research tools to mammalian brains. Recombinant viruses are optimized to mediate regulatable, long-term, and cell-specific gene expression. Here, we describe production methods for three of the most commonly used types of recombinant viruses in neurobiology research: adeno-associated virus (AAV), retrovirus/lentivirus, and glycoprotein-deleted rabies virus. These viral constructs are frequently used for calcium imaging or to deliver neural tracers and optogenetic tools. Popular constructs are readily obtained commercially; however, customized virus production through commercial sources is time consuming and costly. This article aims to provide readers with detailed technical information for rapid production and validation of high-quality viral particles in a laboratory setting while highlighting advantages and limitations of each viral type. © 2019 by John Wiley & Sons, Inc.
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Affiliation(s)
- Shih-Heng Chen
- Viral Vector Core, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
| | - Juhee Haam
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
| | - Mitzie Walker
- Viral Vector Core, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
| | - Erica Scappini
- Signal Transduction Laboratory, Fluorescence Microscopy and Imaging Center, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
| | - John Naughton
- Gene Transfer, Targeting and Therapeutics (GT3) Core, Salk Institute for Biological Studies, La Jolla, California
| | - Negin P Martin
- Viral Vector Core, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH/DHHS, Research Triangle Park, North Carolina
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14
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Parvathi A, Jasna V, Aparna S, Pradeep Ram AS, Aswathy VK, Balachandran KK, Muraleedharan KR, Mathew D, Sime-Ngando T. High Incidence of Lysogeny in the Oxygen Minimum Zones of the Arabian Sea (Southwest Coast of India). Viruses 2018; 10:v10110588. [PMID: 30373217 PMCID: PMC6267222 DOI: 10.3390/v10110588] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 12/24/2022] Open
Abstract
Though microbial processes in the oxygen minimum zones (OMZs) of the Arabian Sea (AS) are well documented, prokaryote-virus interactions are less known. The present study was carried out to determine the potential physico-chemical factors influencing viral abundances and their life strategies (lytic and lysogenic) along the vertical gradient in the OMZ of the AS (southwest coast of India). Water samples were collected during the southwest monsoon (SWM) season in two consecutive years (2015 and 2016) from different depths, namely, the surface layer, secondary chlorophyll a maxima (~30–40 m), oxycline (~70–80 m), and hypoxic/suboxic layers (~200–350 m). The high viral abundances observed in oxygenated surface waters (mean ± SD = 6.1 ± 3.4 × 106 viral-like particles (VLPs) mL−1), drastically decreased with depth in the oxycline region (1.2 ± 0.5 × 106 VLPs mL−1) and hypoxic/suboxic waters (0.3 ± 0.3 × 106 VLPs mL−1). Virus to prokaryote ratio fluctuated in the mixed layer (~10) and declined significantly (p < 0.001) to 1 in the hypoxic layer. Viral production (VP) and frequency of virus infected cells (FIC) were maximum in the surface and minimum in the oxycline layer, whereas the viral lysis was undetectable in the suboxic/hypoxic layer. The detection of a high percentage of lysogeny in suboxic (48%) and oxycline zones (9–24%), accompanied by undetectable rates of lytic viral infection support the hypothesis that lysogeny may represent the major survival strategy for viruses in unproductive or harsh nutrient/host conditions in deoxygenated waters.
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Affiliation(s)
- Ammini Parvathi
- CSIR-National Institute of Oceanography, Regional Centre (CSIR), Kochi 682 018, India.
| | - Vijayan Jasna
- CSIR-National Institute of Oceanography, Regional Centre (CSIR), Kochi 682 018, India.
| | - Sreekumar Aparna
- CSIR-National Institute of Oceanography, Regional Centre (CSIR), Kochi 682 018, India.
| | - Angia Sriram Pradeep Ram
- Laboratoire Microorganismes, Génome et Environnement, UMR CNRS 6023, Université Clermont-Auvergne, 1 Impasse Amélie Murat, 63178 Aubière CEDEX, France.
| | | | | | | | - Dayana Mathew
- CSIR-National Institute of Oceanography, Regional Centre (CSIR), Kochi 682 018, India.
| | - Telesphore Sime-Ngando
- Laboratoire Microorganismes, Génome et Environnement, UMR CNRS 6023, Université Clermont-Auvergne, 1 Impasse Amélie Murat, 63178 Aubière CEDEX, France.
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15
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Wang Z, Wang Y, Wang S, Meng X, Song F, Huo W, Zhang S, Chang J, Li J, Zheng B, Liu Y, Zhang Y, Zhang W, Yu J. Coxsackievirus A6 Induces Cell Cycle Arrest in G0/G1 Phase for Viral Production. Front Cell Infect Microbiol 2018; 8:279. [PMID: 30159255 PMCID: PMC6104138 DOI: 10.3389/fcimb.2018.00279] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 07/25/2018] [Indexed: 11/13/2022] Open
Abstract
Recent epidemiological data indicate that outbreaks of hand, foot, and mouth disease (HFMD), which can be categorized according to its clinical symptoms as typical or atypical, have markedly increased worldwide. A primary causative agent for typical HFMD outbreaks, enterovirus 71 (EV71), has been shown to manipulate the cell cycle in S phase for own replication; however, it is not clear whether coxsackievirus (CVA6), the main agent for atypical HFMD, also regulates the host cell cycle. In this study, we demonstrate for the first time that CVA6 infection arrests the host cell cycle in G0/G1-phase. Furthermore, synchronization in G0/G1 phase, but not S phase or G2/M phase, promotes viral production. To investigate the mechanism of cell cycle arrest induced by CVA6 infection, we analyzed cell cycle progression after cell cycle synchronization at G0/G1 or G2/M. Our results demonstrate that CVA6 infection promotes G0/G1 phase entry from G2/M phase, and inhibits G0/G1 exit into S phase. In line with its role to arrest cells in G0/G1 phase, the expression of cyclinD1, CDK4, cyclinE1, CDK2, cyclinB1, CDK1, P53, P21, and P16 is regulated by CVA6. Finally, the non-structural proteins of CVA6, RNA-dependent RNA polymerase 3D and protease 3C , are demonstrated to be responsible for the G0/G1-phase arrest. These findings suggest that CVA6 infection arrested cell cycle in G0/G1-phase via non-structural proteins 3D and 3C, which may provide favorable environments for virus production.
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Affiliation(s)
- Zengyan Wang
- Department of Internal Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Yue Wang
- Chemistry of Traditional Chinese Medicine, College of Pharmacy, Changchun University of Chinese Medicine, Changchun, China
| | - Shaohua Wang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Xiangling Meng
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin Univrsity, Changchun, China
| | - Fengmei Song
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin Univrsity, Changchun, China
| | - Wenbo Huo
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin Univrsity, Changchun, China
| | - Shuxia Zhang
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin Univrsity, Changchun, China
| | - Junliang Chang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Jingliang Li
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Baisong Zheng
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Yanqiu Liu
- Academy of Integrative Medicine, Dalian Medical University, Dalian, China
| | - Yahong Zhang
- Key Laboratory of Natural Medicines and Immunotechnology of Henan Province, Henan University, Kaifeng, China
| | - Wenyan Zhang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Jinghua Yu
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
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16
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Song F, Yu X, Zhong T, Wang Z, Meng X, Li Z, Zhang S, Huo W, Liu X, Zhang Y, Zhang W, Yu J. Caspase-3 Inhibition Attenuates the Cytopathic Effects of EV71 Infection. Front Microbiol 2018; 9:817. [PMID: 29755438 PMCID: PMC5932146 DOI: 10.3389/fmicb.2018.00817] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 04/10/2018] [Indexed: 12/19/2022] Open
Abstract
Previous studies demonstrate that human enterovirus 71 (EV71), a primary causative agent for hand, foot, and mouth disease, activates caspase-3 through the non-structural viral 3C protein to induce host cell apoptosis; however, until now it was unclear how 3C activates caspase-3 and how caspase-3 activation affects viral production. Our results demonstrate that 3C binds caspase-8 and caspase-9 but does not directly bind caspase-3 to activate them, and that the proteolytic activity of 3C is required by the activation of caspase-8, caspase-9, and caspase-3. Inhibition of caspase-3 activity attenuates apoptosis in 3C-transfected cells. Furthermore, caspase-3 inhibitor protects host cells from the cytopathic effect of EV71 infection and prevents cell cycle arrest, which is known to be favored for EV71 viral replication. Inhibition of caspase-3 activity decreases EV71 viral protein expression and viral production, but has no effect on viral entry, replication, even polyprotein translation. Therefore, caspase-3 is exploited functionally by EV71 to facilitate its production, which suggests a novel therapeutic approach for the treatment and prevention of hand, foot, and mouth disease.
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Affiliation(s)
- Fengmei Song
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China.,Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Xiaoyan Yu
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Ting Zhong
- College of Pharmacy, Central South University, Changsha, China
| | - Zengyan Wang
- Department of Internal Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Xiangling Meng
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Zhaolong Li
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Shuxia Zhang
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Wenbo Huo
- Department of Experimental Pharmacology and Toxicology, School of Pharmacy, Jilin University, Changchun, China
| | - Xin Liu
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Yahong Zhang
- Key Laboratory of Natural Medicines and Immunotechnology of Henan Province, Henan University, Kaifeng, China
| | - Wenyan Zhang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Jinghua Yu
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Jilin University, Changchun, China
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17
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Winter C, Köstner N, Kruspe C, Urban D, Muck S, Reinthaler T, Herndl GJ. Mixing alters the lytic activity of viruses in the dark ocean. Ecology 2018; 99:700-713. [PMID: 29315529 PMCID: PMC5905300 DOI: 10.1002/ecy.2135] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 10/17/2017] [Accepted: 12/18/2017] [Indexed: 11/11/2022]
Abstract
In aquatic habitats, viral lysis of prokaryotic cells lowers the overall efficiency of the microbial loop, by which dissolved organic carbon is transfered to higher trophic levels. Mixing of water masses in the dark ocean occurs on a global scale and may have far reaching consequences for the different prokaryotic and virus communities found in these waters by altering the environmental conditions these communities experience. We hypothesize that mixing of deep ocean water masses enhances the lytic activity of viruses infecting prokaryotes. To address this hypothesis, major deep-sea water masses of the Atlantic Ocean such as North Atlantic Deep Water, Mediterranean Sea Overflow Water, Antarctic Intermediate Water, and Antarctic Bottom Water were sampled at five locations. Prokaryotic cells from these samples were collected by filtration and subsequently incubated in virus-reduced water from either the same (control) or a different water mass (transplantation treatment). Additionally, mixtures of prokaryotes obtained from two different water masses were incubated in a mixture of virus-reduced water from the same water masses (control) or in virus-reduced water from the source water masses separately (mixing treatments). Pronounced differences in productivity-related parameters (prokaryotic leucine incorporation, prokaryotic and viral abundance) between water masses caused strong changes in viral lysis of prokaryotes. Often, mixing of water masses increased viral lysis of prokaryotes, indicating that lysogenic viruses were induced into the lytic cycle. Mixing-induced changes in viral lysis had a strong effect on the community composition of prokaryotes and viruses. Our data show that mixing of deep-sea water masses alters levels of viral lysis of prokaryotes and in many cases weakens the efficiency of the microbial loop by enhancing the recycling of organic carbon in the deep ocean.
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Affiliation(s)
- Christian Winter
- Department of Limnology and Bio‐OceanographyCenter of EcologyUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Nicole Köstner
- Department of Limnology and Bio‐OceanographyCenter of EcologyUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Carl‐Philip Kruspe
- Department of Limnology and Bio‐OceanographyCenter of EcologyUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Damaris Urban
- Department of Limnology and Bio‐OceanographyCenter of EcologyUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Simone Muck
- Department of Limnology and Bio‐OceanographyCenter of EcologyUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Thomas Reinthaler
- Department of Limnology and Bio‐OceanographyCenter of EcologyUniversity of ViennaAlthanstrasse 14Vienna1090Austria
| | - Gerhard J. Herndl
- Department of Limnology and Bio‐OceanographyCenter of EcologyUniversity of ViennaAlthanstrasse 14Vienna1090Austria
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Son K, Nguyen TTT, Choi JW, Pham LV, Luong TTD, Lim YS, Hwang SB. Rad51 Interacts with Non-structural 3 Protein of Hepatitis C Virus and Regulates Viral Production. Front Microbiol 2017; 8:1249. [PMID: 28729862 PMCID: PMC5498509 DOI: 10.3389/fmicb.2017.01249] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 06/21/2017] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) is a leading cause of chronic liver disease affecting over 170 million people worldwide. Chronic infection with HCV progresses to liver fibrosis, cirrhosis, and hepatocellular carcinoma. HCV exploits host cellular factors for viral propagation. To investigate the cellular factors required for HCV propagation, we screened a siRNA library targeting human cell cycle genes using cell culture grown HCV-infected cells. In the present study, we selected and characterized a gene encoding Rad51. Rad51, a member of a conserved recombinase family, is an essential factor for homologous recombination and repair of double-strand DNA breaks. We demonstrated that siRNA-mediated knockdown of Rad51 significantly inhibited HCV propagation without affecting HCV RNA replication. Silencing of Rad51 impaired secretion of infectious HCV particles and thus intracellular viruses were accumulated. We showed that HCV NS3 specifically interacted with Rad51 and accumulated Rad51 in the cytosol. Furthermore, Rad51 was coprecipitated with NS3 and HCV RNA. By employing membrane flotation and protease protection assays, we also demonstrated that Rad51 was co-fractionated with HCV NS3 on the lipid raft. These data indicate that Rad51 may be a component of the HCV RNA replication complex. Collectively, these data suggest that HCV may exploit cellular Rad51 to promote viral propagation and thus Rad51 may be a potential therapeutic target for HCV.
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Affiliation(s)
- Kidong Son
- Department of Biomedical Gerontology, Graduate School of Hallym UniversityChuncheon, South Korea.,National Research Laboratory of Hepatitis C Virus and Ilsong Institute of Life Science, Hallym UniversityAnyang, South Korea.,Environmental Health Research Department, National Institute of Environmental ResearchIncheon, South Korea
| | - Tram T T Nguyen
- Department of Biomedical Gerontology, Graduate School of Hallym UniversityChuncheon, South Korea.,National Research Laboratory of Hepatitis C Virus and Ilsong Institute of Life Science, Hallym UniversityAnyang, South Korea
| | - Jae-Woong Choi
- Department of Biomedical Gerontology, Graduate School of Hallym UniversityChuncheon, South Korea.,National Research Laboratory of Hepatitis C Virus and Ilsong Institute of Life Science, Hallym UniversityAnyang, South Korea
| | - Long V Pham
- Department of Biomedical Gerontology, Graduate School of Hallym UniversityChuncheon, South Korea.,National Research Laboratory of Hepatitis C Virus and Ilsong Institute of Life Science, Hallym UniversityAnyang, South Korea
| | - Trang T D Luong
- Department of Biomedical Gerontology, Graduate School of Hallym UniversityChuncheon, South Korea.,National Research Laboratory of Hepatitis C Virus and Ilsong Institute of Life Science, Hallym UniversityAnyang, South Korea
| | - Yun-Sook Lim
- National Research Laboratory of Hepatitis C Virus and Ilsong Institute of Life Science, Hallym UniversityAnyang, South Korea
| | - Soon B Hwang
- Department of Biomedical Gerontology, Graduate School of Hallym UniversityChuncheon, South Korea.,National Research Laboratory of Hepatitis C Virus and Ilsong Institute of Life Science, Hallym UniversityAnyang, South Korea
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Rastelli E, Dell'Anno A, Corinaldesi C, Middelboe M, Noble RT, Danovaro R. Quantification of Viral and Prokaryotic Production Rates in Benthic Ecosystems: A Methods Comparison. Front Microbiol 2016; 7:1501. [PMID: 27713739 PMCID: PMC5032637 DOI: 10.3389/fmicb.2016.01501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/08/2016] [Indexed: 11/30/2022] Open
Abstract
Viruses profoundly influence benthic marine ecosystems by infecting and subsequently killing their prokaryotic hosts, thereby impacting the cycling of carbon and nutrients. Previously conducted studies, based on different methodologies, have provided widely differing estimates of the relevance of viruses on benthic prokaryotes. There has been no attempt so far to compare these independent approaches, including contextual comparisons among different approaches for sample manipulation (i.e., dilution or not of the sediments during incubations), between methods based on epifluorescence microscopy (EFM) or radiotracers, and between the use of different radiotracers. Therefore, it has been difficult to identify the most suitable methodologies and protocols to be used as standard approaches for the quantification of viral infections of prokaryotes. Here, we compared for the first time different methods for determining viral and prokaryotic production rates in marine sediments collected at two benthic sites, differing in depth and environmental conditions. We used a highly replicated experimental design, testing the potential biases associated to the incubation of sediments as diluted or undiluted. In parallel, we also compared EFM counts with the 3H-thymidine incubations for the determination of viral production rates, and the use of 3H-thymidine versus 3H-leucine radiotracers for the determination of prokaryotic production. We show here that, independent from sediment dilution, EFM-based values of viral production ranged from 1.4 to 4.6 × 107 viruses g-1 h-1, and were similar but overall less variable compared to those obtained by the 3H-thymidine method (0.3 to 9.0 × 107 viruses g-1h-1). In addition, the prokaryotic production rates were not affected by sediment dilution, and the use of different radiotracers provided very consistent estimates (10.3–35.1 and 9.3–34.6 ngC g-1h-1 using the 3H-thymidine or 3H-leucine method, respectively). These results indicated that viral lysis was responsible for the abatement of 55–81% of the prokaryotic heterotrophic production, corroborating previous findings of the major role of viruses in benthic deep-sea ecosystems. Moreover, our methodological comparison for the analysis of viral production in marine sediments suggests that microscopy-based approaches are simpler and more cost-effective than those based on radiotracers. These approaches also reduce time to results and overcome issues related to generation of radioactive waste.
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Affiliation(s)
- Eugenio Rastelli
- Department of Life and Environmental Sciences, Polytechnic University of MarcheAncona, Italy; Stazione Zoologica Anton Dohrn, NaplesItaly
| | - Antonio Dell'Anno
- Department of Life and Environmental Sciences, Polytechnic University of Marche Ancona, Italy
| | - Cinzia Corinaldesi
- Department of Life and Environmental Sciences, Polytechnic University of Marche Ancona, Italy
| | - Mathias Middelboe
- Marine Biological Section, Department of Biology, University of Copenhagen Helsingør, Denmark
| | - Rachel T Noble
- Institute of Marine Sciences, The University of North Carolina at Chapel Hill, Morehead City NC, USA
| | - Roberto Danovaro
- Department of Life and Environmental Sciences, Polytechnic University of MarcheAncona, Italy; Stazione Zoologica Anton Dohrn, NaplesItaly
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Rastelli E, Dell'Anno A, Corinaldesi C, Middelboe M, Noble RT, Danovaro R. Quantification of Viral and Prokaryotic Production Rates in Benthic Ecosystems: A Methods Comparison. Front Microbiol 2016; 7:1501. [PMID: 27713739 DOI: 10.3389/fmicb.2016.0151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/08/2016] [Indexed: 05/26/2023] Open
Abstract
Viruses profoundly influence benthic marine ecosystems by infecting and subsequently killing their prokaryotic hosts, thereby impacting the cycling of carbon and nutrients. Previously conducted studies, based on different methodologies, have provided widely differing estimates of the relevance of viruses on benthic prokaryotes. There has been no attempt so far to compare these independent approaches, including contextual comparisons among different approaches for sample manipulation (i.e., dilution or not of the sediments during incubations), between methods based on epifluorescence microscopy (EFM) or radiotracers, and between the use of different radiotracers. Therefore, it has been difficult to identify the most suitable methodologies and protocols to be used as standard approaches for the quantification of viral infections of prokaryotes. Here, we compared for the first time different methods for determining viral and prokaryotic production rates in marine sediments collected at two benthic sites, differing in depth and environmental conditions. We used a highly replicated experimental design, testing the potential biases associated to the incubation of sediments as diluted or undiluted. In parallel, we also compared EFM counts with the 3H-thymidine incubations for the determination of viral production rates, and the use of 3H-thymidine versus 3H-leucine radiotracers for the determination of prokaryotic production. We show here that, independent from sediment dilution, EFM-based values of viral production ranged from 1.4 to 4.6 × 107 viruses g-1 h-1, and were similar but overall less variable compared to those obtained by the 3H-thymidine method (0.3 to 9.0 × 107 viruses g-1h-1). In addition, the prokaryotic production rates were not affected by sediment dilution, and the use of different radiotracers provided very consistent estimates (10.3-35.1 and 9.3-34.6 ngC g-1h-1 using the 3H-thymidine or 3H-leucine method, respectively). These results indicated that viral lysis was responsible for the abatement of 55-81% of the prokaryotic heterotrophic production, corroborating previous findings of the major role of viruses in benthic deep-sea ecosystems. Moreover, our methodological comparison for the analysis of viral production in marine sediments suggests that microscopy-based approaches are simpler and more cost-effective than those based on radiotracers. These approaches also reduce time to results and overcome issues related to generation of radioactive waste.
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Affiliation(s)
- Eugenio Rastelli
- Department of Life and Environmental Sciences, Polytechnic University of MarcheAncona, Italy; Stazione Zoologica Anton Dohrn, NaplesItaly
| | - Antonio Dell'Anno
- Department of Life and Environmental Sciences, Polytechnic University of Marche Ancona, Italy
| | - Cinzia Corinaldesi
- Department of Life and Environmental Sciences, Polytechnic University of Marche Ancona, Italy
| | - Mathias Middelboe
- Marine Biological Section, Department of Biology, University of Copenhagen Helsingør, Denmark
| | - Rachel T Noble
- Institute of Marine Sciences, The University of North Carolina at Chapel Hill, Morehead City NC, USA
| | - Roberto Danovaro
- Department of Life and Environmental Sciences, Polytechnic University of MarcheAncona, Italy; Stazione Zoologica Anton Dohrn, NaplesItaly
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Kang SH, Kim BG, Lee GM. Justification of continuous packed-bed reactor for retroviral vector production from amphotropic PsiCRIP murine producer cell. Cytotechnology 2000; 34:151-8. [PMID: 19003389 PMCID: PMC3449741 DOI: 10.1023/a:1008120313175] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To indentify a plausible large-scale production system forretroviral vector, three culture systems, i.e., batch culturewith medium exchange, microcarrier culture, and packed-bedreactor culture were compared. In batch cultures with mediumexchange, high cell concentrations were maintained for about amonth, and the harvested retroviral titer remained constant. Inmicrocarrier cultures, although cell growth was rapid, theretroviral titer was unexpectedly low, suggesting that the lowtiter was due either to serious damage to the retroviral vectoror to a reduction in the production rate of retroviral vector,caused by mechanical shear forces. Although the retroviral titer(maximum titer, 1.56 x 10(6)) in the packed-bedreactor was a little bit lower than that obtained in the batchculture with medium exchange (maximum titer, 1.91 x10(6)), continuous production made it possible to increasethe cumulative titer up to 16-fold of that from the batchculture with medium exchange. Moreover, as the packed-bedreactor system requires less labor and shows excellentvolumetric productivity in comparison to batch cultures withmedium exchanges, it will be an appropriate production systemfor retroviral vector in large quantities.
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Affiliation(s)
- S H Kang
- School of Chemical Engineering, Institute for Molecular Biology and Genetics, Seoul National University, Seoul, 151-742, Korea
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