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Downey J, Pernet E, Coulombe F, Divangahi M. Dissecting host cell death programs in the pathogenesis of influenza. Microbes Infect 2018; 20:560-569. [PMID: 29679740 PMCID: PMC7110448 DOI: 10.1016/j.micinf.2018.03.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 03/27/2018] [Accepted: 03/28/2018] [Indexed: 02/06/2023]
Abstract
Influenza A virus (IAV) is a pulmonary pathogen, responsible for significant yearly morbidity and mortality. Due to the absence of highly effective antiviral therapies and vaccine, as well as the constant threat of an emerging pandemic strain, there is considerable need to better understand the host-pathogen interactions and the factors that dictate a protective versus detrimental immune response to IAV. Even though evidence of IAV-induced cell death in human pulmonary epithelial and immune cells has been observed for almost a century, very little is known about the consequences of cell death on viral pathogenesis. Recent study indicates that both the type of cell death program and its kinetics have major implications on host defense and survival. In this review, we discuss advances in our understanding of cell death programs during influenza virus infection, in hopes of fostering new areas of investigation for targeted clinical intervention.
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Affiliation(s)
- Jeffrey Downey
- Department of Medicine, Department of Microbiology & Immunology, Department of Pathology, McGill University Health Centre, McGill International TB Centre, Meakins-Christie Laboratories, McGill University, 1001 Decarie Boulevard, Montreal, Quebec H4A 3J1, Canada
| | - Erwan Pernet
- Department of Medicine, Department of Microbiology & Immunology, Department of Pathology, McGill University Health Centre, McGill International TB Centre, Meakins-Christie Laboratories, McGill University, 1001 Decarie Boulevard, Montreal, Quebec H4A 3J1, Canada
| | - François Coulombe
- Department of Medicine, Department of Microbiology & Immunology, Department of Pathology, McGill University Health Centre, McGill International TB Centre, Meakins-Christie Laboratories, McGill University, 1001 Decarie Boulevard, Montreal, Quebec H4A 3J1, Canada
| | - Maziar Divangahi
- Department of Medicine, Department of Microbiology & Immunology, Department of Pathology, McGill University Health Centre, McGill International TB Centre, Meakins-Christie Laboratories, McGill University, 1001 Decarie Boulevard, Montreal, Quebec H4A 3J1, Canada.
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Taye B, Chen H, Myaing MZ, Tan BH, Maurer-Stroh S, Sugrue RJ. Systems-based approach to examine the cytokine responses in primary mouse lung macrophages infected with low pathogenic avian Influenza virus circulating in South East Asia. BMC Genomics 2017; 18:420. [PMID: 28558796 PMCID: PMC5450074 DOI: 10.1186/s12864-017-3803-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 05/17/2017] [Indexed: 02/08/2023] Open
Abstract
Background Influenza A virus (IAV) is a major public health concern, being responsible for the death of approximately half a million people each year. Zoonotic transmissions of the virus from swine and avian origin have occurred in the past, and can potentially lead to the emgergence of new IAV stains in future pandemics. Pulmonary macrophages have been implicated in disease severity in the lower airway, and understanding the host response of macrophages infected with avian influenza viruses should provide new therapeutic strategies. Results We used a systems-based approach to investigate the transcriptome response of primary murine lung macrophages (PMФ) infected with the mouse-adapted H1N1/WSN virus and low pathogenic avian influenza (LPAI) viruses H5N2 and H5N3. The results showed that the LPAI viruses H5N2 and H5N3 can infect PMФ with similar efficiency to the H1N1/WSN virus. While all viruses induced antiviral responses, the H5N3 virus infection resulted in higher expression levels of cytokines and chemokines associated with inflammatory responses. Conclusions The LPAI H5N2 and H5N3 viruses are able to infect murine lung macrophages. However, the H5N3 virus was associated with increased expression of pro-inflammatory mediators. Although the H5N3 virus it is capable of inducing high levels of cytokines that are associated with inflammation, this property is distinct from its inability to efficiently replicate in a mammalian host. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3803-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Biruhalem Taye
- Bioinformatics Institute, A*STAR, 30 Biopolis Street #07-01, Matrix, Singapore, 138671, Republic of Singapore.,School of Biological Science, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.,Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, P.O.BOX 1176, Ethiopia
| | - Hui Chen
- School of Biological Science, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.,Current address Genome Institute of Singapore, A*STAR, 60 Biopolis Street, #02-01, Genome, Singapore, 138672, Republic of Singapore
| | - Myint Zu Myaing
- School of Biological Science, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Boon Huan Tan
- Detection and Diagnostics Laboratory, Defence Science Organisation National Laboratories, 27 Medical Drive, Singapore, 117510, Republic of Singapore.,LKC School of Medicine, Nanyang Technological University, 50 Nanyang Ave, Singapore, 639798, Republic of Singapore
| | - Sebastian Maurer-Stroh
- Bioinformatics Institute, A*STAR, 30 Biopolis Street #07-01, Matrix, Singapore, 138671, Republic of Singapore.,National Public Health Laboratory, Ministry of Health, Singapore, Republic of Singapore.,Department of Biological Sciences, National University of Singapore, 8 Medical Drive, Singapore, 117597, Republic of Singapore
| | - Richard J Sugrue
- School of Biological Science, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.
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Sgarbanti R, Amatore D, Celestino I, Marcocci ME, Fraternale A, Ciriolo MR, Magnani M, Saladino R, Garaci E, Palamara AT, Nencioni L. Intracellular redox state as target for anti-influenza therapy: are antioxidants always effective? Curr Top Med Chem 2015; 14:2529-41. [PMID: 25478883 PMCID: PMC4435240 DOI: 10.2174/1568026614666141203125211] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 10/29/2014] [Accepted: 11/02/2014] [Indexed: 12/12/2022]
Abstract
Influenza virus infections represent a big issue for public health since effective treatments are still lacking. In particular, the emergence of strains resistant to drugs limits the effectiveness of anti-influenza agents. For this reason, many efforts have been dedicated to the identification of new therapeutic strategies aimed at targeting the virus-host cell interactions. Oxidative stress is a characteristic of some viral infections including influenza. Because antioxidants defend cells from damage caused by reactive oxygen species induced by different stimuli including pathogens, they represent interesting molecules to fight infectious diseases. However, most of the available studies have found that these would-be panaceas could actually exacerbate the diseases they claim to prevent, and have thus revealed "the dark side" of these molecules. This review article discusses the latest opportunities and drawbacks of the antioxidants used in anti-influenza therapy and new perspectives.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Lucia Nencioni
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy.
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Cannon G, Callahan MA, Gronemus JQ, Lowy RJ. Early activation of MAP kinases by influenza A virus X-31 in murine macrophage cell lines. PLoS One 2014; 9:e105385. [PMID: 25166426 PMCID: PMC4148262 DOI: 10.1371/journal.pone.0105385] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 07/23/2014] [Indexed: 12/17/2022] Open
Abstract
Early molecular responses to Influenza A (FLUA) virus strain A/X-31 H3N2 in macrophages were explored using J774.A1 and RAW 264.7 murine cell lines. NF-kappa B (NFκB) was reported to be central to FLUA host-response in other cell types. Our data showed that FLUA activation of the classical NFκB dependent pathway in these macrophages was minimal. Regulator proteins, IkappaB-alpha and -beta (IκBα, IκBβ), showed limited degradation peaking at 2 h post FLUA exposure and p65 was not observed to translocate from the cytoplasm to the nucleus. Additionally, the non-canonical NFκB pathway was not activated in response to FLUA. The cells did display early increases in TNFα and other inflammatory cytokine and chemokine production. Mitogen activated phosphokinase (MAPK) signaling pathways are also reported to control production of inflammatory cytokines in response to FLUA. The activation of the MAPKs, cJun kinases 1 and 2 (JNK 1/2), extracellular regulated kinases 1 and 2 (ERK 1/2), and p38 were investigated in both cell lines between 0.25 and 3 h post-infection. Each of these kinases showed increased phosphorylation post FLUA exposure. JNK phosphorylation occurred early while p38 phosphorylation appeared later. Phosphorylation of ERK 1/2 occurred earlier in J774.A1 cells compared to RAW 264.7 cells. Inhibition of MAPK activation resulted in decreased production of most FLUA responsive cytokines and chemokines in these cells. The results suggest that in these monocytic cells the MAPK pathways are important in the early response to FLUA.
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Affiliation(s)
- Georgetta Cannon
- Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - Michelle A. Callahan
- Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - Jenny Q. Gronemus
- Central Accessing Unit, American Type Culture Collection, Manassas, Virginia, United States of America
| | - R. Joel Lowy
- Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
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Hassan EA, Zayed SE. Dithiocarbamates as Precursors in Organic Chemistry; Synthesis and Uses. PHOSPHORUS SULFUR 2014. [DOI: 10.1080/10426507.2013.797416] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Entesar A. Hassan
- a Department of Chemistry, Faculty of Science , South Valley University , Qena , Egypt
| | - Salem E. Zayed
- a Department of Chemistry, Faculty of Science , South Valley University , Qena , Egypt
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Uchide N, Toyoda H. Antioxidant therapy as a potential approach to severe influenza-associated complications. MOLECULES (BASEL, SWITZERLAND) 2011; 16. [PMID: 21358592 PMCID: PMC6259602 DOI: 10.3390/molecules23100000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
With the appearance of the novel influenza A (H1N1) virus 2009 strain we have experienced a new influenza pandemic and many patients have died from severe complications associated with this pandemic despite receiving intensive care. This suggests that a definitive medical treatment for severe influenza-associated complications has not yet been established. Many studies have shown that superoxide anion produced by macrophages infiltrated into the virus-infected organs is implicated in the development of severe influenza-associated complications. Selected antioxidants, such as pyrrolidine dithiocabamate, N-acetyl-L-cysteine, glutathione, nordihydroguaiaretic acid, thujaplicin, resveratrol, (+)-vitisin A, ambroxol, ascorbic acid, 5,7,4-trihydroxy-8-methoxyflavone, catechins, quercetin 3-rhamnoside, iso- quercetin and oligonol, inhibit the proliferation of influenza virus and scavenge superoxide anion. The combination of antioxidants with antiviral drugs synergistically reduces the lethal effects of influenza virus infections. These results suggest that an agent with antiviral and antioxidant activities could be a drug of choice for the treatment of patients with severe influenza-associated complications. This review article updates knowledge of antioxidant therapy as a potential approach to severe influenza-associated complications.
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Affiliation(s)
- Noboru Uchide
- Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
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Antioxidant Therapy as a Potential Approach to Severe Influenza-Associated Complications. Molecules 2011; 16:2032-52. [DOI: 10.3390/molecules16032032] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 02/23/2011] [Accepted: 02/25/2011] [Indexed: 12/24/2022] Open
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Shao J, Lathdavong L, Westberg J, Kluczynski P, Lundqvist S, Axner O. Faraday modulation spectrometry of nitric oxide addressing its electronic X2Π - A2Σ+ band: II. Experiment. APPLIED OPTICS 2010; 49:5614-5625. [PMID: 20935708 DOI: 10.1364/ao.49.005614] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A first demonstration of Faraday modulation spectrometry (FAMOS) of nitric oxide (NO) addressing its strong electronic X(2)Π(ν″ = 0) - A(2)Σ(+)(ν(') = 0) band is presented. The instrumentation was constructed around a fully diode-laser-based laser system producing mW powers of ultraviolet light targeting the overlapping Q(22)(21/2) and R(12)Q(21/2) transitions at ∼226.6 nm. The work verifies a new two-transition model of FAMOS addressing the electronic transitions in NO given in an accompanying work. Although the experimental instrumentation could address neither the parameter space of the theory nor the optimum conditions, the line shapes and the pressure dependence could be verified under low-field conditions. NO could be detected down to a partial pressure of 13 µTorr, roughly corresponding to 10 ppb·m for an atmospheric pressure sample, which demonstrates the feasibility of FAMOS for sensitive detection of NO addressing its strong electronic band.
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Affiliation(s)
- Jie Shao
- Institute of Information Optics of Zhejiang Normal University, 321004 Jinhua, China
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Imai Y, Kuba K, Neely GG, Yaghubian-Malhami R, Perkmann T, van Loo G, Ermolaeva M, Veldhuizen R, Leung YHC, Wang H, Liu H, Sun Y, Pasparakis M, Kopf M, Mech C, Bavari S, Peiris JSM, Slutsky AS, Akira S, Hultqvist M, Holmdahl R, Nicholls J, Jiang C, Binder CJ, Penninger JM. Identification of oxidative stress and Toll-like receptor 4 signaling as a key pathway of acute lung injury. Cell 2008; 133:235-49. [PMID: 18423196 PMCID: PMC7112336 DOI: 10.1016/j.cell.2008.02.043] [Citation(s) in RCA: 1037] [Impact Index Per Article: 64.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Revised: 12/10/2007] [Accepted: 02/29/2008] [Indexed: 12/01/2022]
Abstract
Multiple lung pathogens such as chemical agents, H5N1 avian flu, or SARS cause high lethality due to acute respiratory distress syndrome. Here we report that Toll-like receptor 4 (TLR4) mutant mice display natural resistance to acid-induced acute lung injury (ALI). We show that TLR4-TRIF-TRAF6 signaling is a key disease pathway that controls the severity of ALI. The oxidized phospholipid (OxPL) OxPAPC was identified to induce lung injury and cytokine production by lung macrophages via TLR4-TRIF. We observed OxPL production in the lungs of humans and animals infected with SARS, Anthrax, or H5N1. Pulmonary challenge with an inactivated H5N1 avian influenza virus rapidly induces ALI and OxPL formation in mice. Loss of TLR4 or TRIF expression protects mice from H5N1-induced ALI. Moreover, deletion of ncf1, which controls ROS production, improves the severity of H5N1-mediated ALI. Our data identify oxidative stress and innate immunity as key lung injury pathways that control the severity of ALI.
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Affiliation(s)
- Yumiko Imai
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohrgasse 3, A-1030 Vienna, Austria.
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Yang S, Liu W, Cui H, Sun S, Wang J. In vitro induction of apoptosis in tumor cells by inactivated NDV and IAV. Cancer Biother Radiopharm 2007; 22:200-5. [PMID: 17600467 DOI: 10.1089/cbr.2007.337] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We examined how Newcastle disease virus (NDV) and influenza A virus (IAV) inactivated by 5% formaldehyde, used either alone or in combination, can induce apoptosis in both HeLa and SP2/0 cells. Inactive NDV and IAV demonstrated enhanced rates of lysis in apoptotic tumor cells and greater antitumor effects when combined. Our study supports the argument that viral replication does not cause virally induced apoptosis.
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Affiliation(s)
- ShuYan Yang
- Laboratory of Biochemistry and Molecular Biology, College of Biological Sciences, China, Agricultural University, Beijing, China
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Zhirnov OP, Klenk HD. Control of apoptosis in influenza virus-infected cells by up-regulation of Akt and p53 signaling. Apoptosis 2007; 12:1419-32. [PMID: 17468837 DOI: 10.1007/s10495-007-0071-y] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
PI3k-Akt and p53 pathways are known to play anti- and pro-apoptotic roles in cell death, respectively. Whether these pathways are recruited in influenza virus infection in highly productive monkey (CV-1) and canine (MDCK) kidney cells was studied here. Phosphorylation of Akt (Akt-pho) was found to occur only early after infection (5-9 h.p.i). Nuclear accumulation and phosphorylation of p53 (p53-pho), and expression of its natural target p21/waf showed low constitutive levels at this period, whereas all three parameters were markedly elevated at the late apoptotic stage (17-20 h.p.i.). Up-regulation of Akt-pho and p53-pho was not induced by UV-inactivated virus suggesting that it required virus replication. Also, mRNAs of p53 and its natural antagonist mdm2 were not increased throughout infection indicating that p53-pho was up-regulated by posttranslational mechanisms. However, p53 activation did not seem to play a leading role in influenza-induced cell death: (i) infection of CV1 and MDCK cells with recombinant NS1-deficient virus provoked accelerated apoptotic death characterized by the lack of p53 activation; (ii) mixed apoptosis-necrosis death developed in influenza-infected human bronchial H1299 cells carrying a tetracycline-regulated p53 gene did not depend on p53 gene activation by tetracycline. Virus-induced apoptosis and signaling of Akt and p53 developed in IFN-deficient VERO cells with similar kinetics as in IFN-competent CV1-infected cells indicating that these processes were endocrine IFN-independent. Apoptosis in influenza-infected CV-1 and MDCK cells was Akt-dependent and was accelerated by Ly294002, a specific inhibitor of PI3k-Akt signaling, and down-regulated by the viral protein NS1, an inducer of host Akt. The obtained data suggest that influenza virus (i) initiates anti-apoptotic PI3k-Akt signaling at early and middle phases of infection to protect cells from fast apoptotic death and (ii) provokes both p53-dependent and alternative p53-independent apoptotic and/or necrotic (in some host systems) cell death at the late stage of infection.
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Affiliation(s)
- Oleg P Zhirnov
- D.I. Ivanovsky Institute of Virology, Moscow 123098, Russia.
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Uchide N, Suzuki A, Ohyama K, Bessho T, Toyoda H. Secretion of bioactive interleukin-6 and tumor necrosis factor-alpha proteins from primary cultured human fetal membrane chorion cells infected with influenza virus. Placenta 2005; 27:678-90. [PMID: 16122792 DOI: 10.1016/j.placenta.2005.06.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Revised: 05/26/2005] [Accepted: 06/10/2005] [Indexed: 10/25/2022]
Abstract
Influenza virus infection during pregnancy is implicated in one of the causes of premature delivery, abortion and stillbirth. Pro-inflammatory cytokines, such as interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha produced by fetal membranes, are postulated to facilitate premature delivery. We investigated the secretion of IL-6 and TNF-alpha from primary cultured human fetal membrane chorion and amnion cells infected with influenza virus at protein and bioactivity levels in order to understand the pathology of premature delivery during influenza virus infection. Concentrations of IL-6 and TNF-alpha proteins were significantly increased in culture supernatants of chorion cells by influenza virus infection. Culture supernatants of the virus-infected chorion cells stimulated the proliferation of IL-6-sensitive 7-TD-1 cells and induced the cytolysis of TNF-alpha-sensitive L929 cells, both activities of which were inhibited by the addition of respective antibody, whereas no such phenomena were observed in amnion cells. The results demonstrated that only chorion cells secreted significant amounts of bioactive IL-6 and TNF-alpha proteins responding to influenza virus infection. The present study suggests a possibility that the secretion of bioactive IL-6 and TNF-alpha proteins from fetal membrane chorion cells is implicated in the pathogenesis of premature delivery during influenza virus infection.
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Affiliation(s)
- N Uchide
- Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
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Turpin E, Luke K, Jones J, Tumpey T, Konan K, Schultz-Cherry S. Influenza virus infection increases p53 activity: role of p53 in cell death and viral replication. J Virol 2005; 79:8802-11. [PMID: 15994774 PMCID: PMC1168730 DOI: 10.1128/jvi.79.14.8802-8811.2005] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2005] [Accepted: 03/28/2005] [Indexed: 11/20/2022] Open
Abstract
The induction of apoptotic cell death is a hallmark of influenza virus infection. Although a variety of cellular and viral proteins have been implicated in this process, to date no conserved cellular pathway has been identified. In this study, we report that the tumor suppressor protein p53 is essential for the induction of cell death in influenza virus-infected cells. In primary human lung cells, influenza virus increased p53 protein levels. This was also noted in the human lung cell line A549, along with the up-regulation of p53-dependent gene transcription. Reduction of p53 activity in A549 cells inhibited influenza virus-induced cell death as measured by trypan blue exclusion and caspase activity. These findings were not cell type specific. Influenza virus-induced cell death was absent in mouse embryo fibroblasts isolated from p53 knockout mice, which was not the case in wild-type mouse embryo fibroblasts, suggesting that p53 is a common cellular pathway leading to influenza virus-induced cell death. Surprisingly, inhibiting p53 activity led to elevated virus replication. Mechanistically, this may be due to the decrease in interferon signaling in p53-deficient cells, suggesting that functional p53 is involved in the interferon response to influenza infection. To our knowledge, these are the first studies demonstrating that p53 is involved in influenza virus-induced cell death and that inhibiting p53 leads to increased viral titers, potentially through modulation of the interferon response.
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Affiliation(s)
- Elizabeth Turpin
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison 53706, USA
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