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Sample records for choriomeningitis virus-induced immunopathology

  1. Lymphocytic Choriomeningitis Virus Differentially Affects the Virus-Induced Type I Interferon Response and Mitochondrial Apoptosis Mediated by RIG-I/MAVS

    PubMed Central

    Pythoud, Christelle; Rothenberger, Sylvia; Martínez-Sobrido, Luis; de la Torre, Juan Carlos

    2015-01-01

    ABSTRACT Arenaviruses are important emerging human pathogens maintained by noncytolytic persistent infection in their rodent reservoir hosts. Despite high levels of viral replication, persistently infected carrier hosts show only mildly elevated levels of type I interferon (IFN-I). Accordingly, the arenavirus nucleoprotein (NP) has been identified as a potent IFN-I antagonist capable of blocking activation of interferon regulatory factor 3 (IRF3) via the retinoic acid inducible gene (RIG)-I/mitochondrial antiviral signaling (MAVS) pathway. Another important mechanism of host innate antiviral defense is represented by virus-induced mitochondrial apoptosis via RIG-I/MAVS and IRF3. In the present study, we investigated the ability of the prototypic Old World arenavirus lymphocytic choriomeningitis virus (LCMV) to interfere with RIG-I/MAVS-dependent apoptosis. We found that LCMV does not induce apoptosis at any time during infection. While LCMV efficiently blocked induction of IFN-I via RIG-I/MAVS in response to superinfection with cytopathic RNA viruses, virus-induced mitochondrial apoptosis remained fully active in LCMV-infected cells. Notably, in LCMV-infected cells, RIG-I was dispensable for virus-induced apoptosis via MAVS. Our study reveals that LCMV infection efficiently suppresses induction of IFN-I but does not interfere with the cell's ability to undergo virus-induced mitochondrial apoptosis as a strategy of innate antiviral defense. The RIG-I independence of mitochondrial apoptosis in LCMV-infected cells provides the first evidence that arenaviruses can reshape apoptotic signaling according to their needs. IMPORTANCE Arenaviruses are important emerging human pathogens that are maintained in their rodent hosts by persistent infection. Persistent virus is able to subvert the cellular interferon response, a powerful branch of the innate antiviral defense. Here, we investigated the ability of the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) to

  2. Prevention of Influenza Virus-Induced Immunopathology by TGF-β Produced during Allergic Asthma

    PubMed Central

    Furuya, Yoichi; Furuya, Andrea K. M.; Roberts, Sean; Sanfilippo, Alan M.; Salmon, Sharon L.; Metzger, Dennis W.

    2015-01-01

    Asthma is believed to be a risk factor for influenza infection, however little experimental evidence exists to directly demonstrate the impact of asthma on susceptibility to influenza infection. Using a mouse model, we now report that asthmatic mice are actually significantly more resistant to a lethal influenza virus challenge. Notably, the observed increased resistance was not attributable to enhanced viral clearance, but instead, was due to reduced lung inflammation. Asthmatic mice exhibited a significantly reduced cytokine storm, as well as reduced total protein levels and cytotoxicity in the airways, indicators of decreased tissue injury. Further, asthmatic mice had significantly increased levels of TGF-β1 and the heightened resistance of asthmatic mice was abrogated in the absence of TGF-β receptor II. We conclude that a transient increase in TGF-β expression following acute asthma can induce protection against influenza-induced immunopathology. PMID:26407325

  3. COPD immunopathology.

    PubMed

    Caramori, Gaetano; Casolari, Paolo; Barczyk, Adam; Durham, Andrew L; Di Stefano, Antonino; Adcock, Ian

    2016-07-01

    The immunopathology of chronic obstructive pulmonary disease (COPD) is based on the innate and adaptive inflammatory immune responses to the chronic inhalation of cigarette smoking. In the last quarter of the century, the analysis of specimens obtained from the lower airways of COPD patients compared with those from a control group of age-matched smokers with normal lung function has provided novel insights on the potential pathogenetic role of the different cells of the innate and acquired immune responses and their pro/anti-inflammatory mediators and intracellular signalling pathways, contributing to a better knowledge of the immunopathology of COPD both during its stable phase and during its exacerbations. This also has provided a scientific rationale for new drugs discovery and targeting to the lower airways. This review summarises and discusses the immunopathology of COPD patients, of different severity, compared with control smokers with normal lung function. PMID:27178410

  4. Reactive oxygen species delay control of lymphocytic choriomeningitis virus

    PubMed Central

    Lang, P A; Xu, H C; Grusdat, M; McIlwain, D R; Pandyra, A A; Harris, I S; Shaabani, N; Honke, N; Kumar Maney, S; Lang, E; Pozdeev, V I; Recher, M; Odermatt, B; Brenner, D; Häussinger, D; Ohashi, P S; Hengartner, H; Zinkernagel, R M; Mak, T W; Lang, K S

    2013-01-01

    Cluster of differentiation (CD)8+ T cells are like a double edged sword during chronic viral infections because they not only promote virus elimination but also induce virus-mediated immunopathology. Elevated levels of reactive oxygen species (ROS) have been reported during virus infections. However, the role of ROS in T-cell-mediated immunopathology remains unclear. Here we used the murine lymphocytic choriomeningitis virus to explore the role of ROS during the processes of virus elimination and induction of immunopathology. We found that virus infection led to elevated levels of ROS producing granulocytes and macrophages in virus-infected liver and spleen tissues that were triggered by the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Lack of the regulatory subunit p47phox of the NADPH oxidase diminished ROS production in these cells. While CD8+ T cells exhibited ROS production that was independent of NADPH oxidase expression, survival and T-cell function was elevated in p47phox-deficient (Ncf1−/−) mice. In the absence of p47phox, enhanced T-cell immunity promoted virus elimination and blunted corresponding immunopathology. In conclusion, we find that NADPH-mediated production of ROS critically impairs the immune response, impacting elimination of virus and outcome of liver cell damage. PMID:23328631

  5. Immunopathology of multiple sclerosis.

    PubMed

    Dendrou, Calliope A; Fugger, Lars; Friese, Manuel A

    2015-09-15

    Two decades of clinical experience with immunomodulatory treatments for multiple sclerosis point to distinct immunological pathways that drive disease relapses and progression. In light of this, we discuss our current understanding of multiple sclerosis immunopathology, evaluate long-standing hypotheses regarding the role of the immune system in the disease and delineate key questions that are still unanswered. Recent and anticipated advances in the field of immunology, and the increasing recognition of inflammation as an important component of neurodegeneration, are shaping our conceptualization of disease pathophysiology, and we explore the potential implications for improved healthcare provision to patients in the future. PMID:26250739

  6. Vaccine-Elicited CD4 T Cells Induce Immunopathology Following Chronic LCMV Infection

    PubMed Central

    Penaloza-MacMaster, Pablo; Barber, Daniel L.; Wherry, E. John; Provine, Nicholas M.; Teigler, Jeffrey E.; Parenteau, Lily; Blackmore, Stephen; Borducchi, Erica N.; Larocca, Rafael A.; Yates, Kathleen B.; Shen, Hao; Haining, W. Nicholas; Sommerstein, Rami; Pinschewer, Daniel D.; Ahmed, Rafi; Barouch, Dan. H.

    2015-01-01

    CD4 T cells promote innate and adaptive immune responses, but how vaccine-elicited CD4 T cells contribute to immune protection remains unclear. Here we evaluated whether induction of virus-specific CD4 T cells by vaccination would protect mice against infection with chronic lymphocytic choriomeningitis virus (LCMV). Immunization with vaccines that selectively induced CD4 T cell responses resulted in catastrophic inflammation and mortality following challenge with a persistent strain of LCMV. Immunopathology required antigen-specific CD4 T cells and was associated with a cytokine storm, generalized inflammation, and multi-organ system failure. Virus-specific CD8 T cells or antibodies abrogated the pathology. These data demonstrate that vaccine-elicited CD4 T cells in the absence of effective antiviral immune responses can trigger lethal immunopathology. PMID:25593185

  7. The Lymphocytic Choriomeningitis Virus Matrix Protein PPXY Late Domain Drives the Production of Defective Interfering Particles

    PubMed Central

    Ziegler, Christopher M.; Eisenhauer, Philip; Bruce, Emily A.; Weir, Marion E.; King, Benjamin R.; Klaus, Joseph P.; Krementsov, Dimitry N.; Shirley, David J.; Ballif, Bryan A.; Botten, Jason

    2016-01-01

    Arenaviruses cause severe diseases in humans but establish asymptomatic, lifelong infections in rodent reservoirs. Persistently-infected rodents harbor high levels of defective interfering (DI) particles, which are thought to be important for establishing persistence and mitigating virus-induced cytopathic effect. Little is known about what drives the production of DI particles. We show that neither the PPXY late domain encoded within the lymphocytic choriomeningitis virus (LCMV) matrix protein nor a functional endosomal sorting complex transport (ESCRT) pathway is absolutely required for the generation of standard infectious virus particles. In contrast, DI particle release critically requires the PPXY late domain and is ESCRT-dependent. Additionally, the terminal tyrosine in the PPXY motif is reversibly phosphorylated and our findings indicate that this posttranslational modification may regulate DI particle formation. Thus we have uncovered a new role for the PPXY late domain and a possible mechanism for its regulation. PMID:27010636

  8. Immunopathology of Schistosoma mansoni infection.

    PubMed Central

    Boros, D L

    1989-01-01

    Schistosomiasis mansoni is a chronic helminthic disease that affects about 100 million people in the tropics. The worms have a life span of 5 to 10 years, and they live in the mesenteric veins of the host. Lightly infected individuals are asymptomatic or manifest mild intestinal symptoms. Heavily infected individuals often develop severe morbidity with hepatosplenomegaly, sometimes with a fatal outcome. Morbidity is attributed to the strong humoral and T-cell-mediated host immune responses developed to a variety of parasite antigens and expressed as tissue inflammations. The immunopathology includes dermatitis, immune complex-mediated kidney disease, and, chiefly, T-cell-mediated granuloma formation and fibrosis around disseminated parasite eggs. This review describes the mechanisms of induction and expression of immunopathology in infected persons and experimental animals. Immunoregulatory mechanisms that modulate the enhanced immune responses and may ameliorate excessive morbidity are discussed. PMID:2504481

  9. Dendritic cells in lung immunopathology.

    PubMed

    Cook, Peter C; MacDonald, Andrew S

    2016-07-01

    Dendritic cells (DCs) lie at the heart of the innate immune system, specialised at recognising danger signals in many forms including foreign material, infection or tissue damage and initiating powerful adaptive immune and inflammatory responses. In barrier sites such as the lung, the instrumental role that DCs play at the interface between the environment and the host places them in a pivotal position in determining the severity of inflammatory disease. The past few years has seen a significant increase in our fundamental understanding of the subsets of DCs involved in pulmonary immunity, as well as the mechanisms by which they are activated and which they may use to coordinate downstream inflammation and pathology. In this review, we will summarise current understanding of the multi-faceted role that DCs play in the induction, maintenance and regulation of lung immunopathology, with an emphasis on allergic pulmonary disease. PMID:27256370

  10. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section 866.3360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological...

  11. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section 866.3360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological...

  12. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section 866.3360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological...

  13. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section 866.3360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological...

  14. 21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section 866.3360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological...

  15. Narcolepsy with cataplexy and comorbid immunopathological diseases.

    PubMed

    Martínez-Orozco, Francisco J; Vicario, José L; Villalibre-Valderrey, Isabel; De Andrés, Clara; Fernández-Arquero, Miguel; Peraita-Adrados, Rosa

    2014-08-01

    Evidence suggests that autoimmune diseases tend to co-occur so that patients with an autoimmune disorder are at higher risk of a second autoimmune disease. The association between allergic and autoimmune diseases is also of considerable interest. There are no reports on the association between sporadic or familial narcolepsy with cataplexy and other non-neurological immune-mediated diseases. This study reported on the comorbid immunopathological diseases associated with narcolepsy. One-hundred and fifty six narcoleptic patients with a mean age at diagnosis of 39.1 ± 17.8 years (range, 6-70 years) were assessed using the clinical history, physical and neurological examinations, sleep questionnaires, neuroimaging and human leucocyte antigen typing. Diagnosis was confirmed by polysomnography followed by a multiple sleep latency test or by measuring hypocretin-1 levels. Patients with immunopathological diseases were matched for gender and age at the onset of narcoleptic symptoms with narcoleptic patients without immunopathological diseases. Twenty-six patients (16.6%; 50% women; one familial, 25 sporadic) had one or more immunopathological diseases associated: autoimmune diseases, such as idiopathic thrombocytopenic purpura, multiple sclerosis, systemic lupus erythematosus, psoriasis, Crohn's disease, ulcerative colitis, autoimmune thyroid disease, Peyronie's disease and idiopathic recurrent facial palsy; other immunopathological diseases, like atopic dermatitis, allergic asthma and allergic rhinitis. Although not significant, the age at diagnosis of narcolepsy was 9.3 years earlier in patients with narcolepsy + immunopathological diseases. The results demonstrate that the prevalence of comorbid immunopathological diseases is high in narcolepsy, and cataplexy is significantly more severe in patients with narcolepsy + immunopathological diseases. PMID:24645699

  16. Cross-priming of CD8+ T cells stimulated by virus-induced type I interferon.

    PubMed

    Le Bon, Agnes; Etchart, Nathalie; Rossmann, Cornelia; Ashton, Miranda; Hou, Sam; Gewert, Dirk; Borrow, Persephone; Tough, David F

    2003-10-01

    CD8+ T cell responses can be generated against antigens that are not expressed directly within antigen-presenting cells (APCs), through a process known as cross-priming. To initiate cross-priming, APCs must both capture extracellular antigen and receive specific activation signals. We have investigated the nature of APC activation signals associated with virus infection that stimulate cross-priming. We show that infection with lymphocytic choriomeningitis virus induces cross-priming by a mechanism dependent on type I interferon (IFN-alpha/beta). Activation of cross-priming by IFN-alpha/beta was independent of CD4+ T cell help or interaction of CD40 and CD40 ligand, and involved direct stimulation of dendritic cells. These data identify expression of IFN-alpha/beta as a mechanism for the induction of cross-priming during virus infections. PMID:14502286

  17. On the origin of immunopathology.

    PubMed

    Vaz, Nelson M; Carvalho, Claudia R

    2015-06-21

    Stranded between medicine and experimental biology, immunology is buried in its own problems and remains distant from important areas of current biology, such as evolutionary theory, developmental biology and cognitive sciences. Immunology has treated the living system merely as the place or dimension in which immune activity takes place, inserted on a misleading axis (progressive responsiveness versus no response; memory versus tolerance) which neglects the analysis of a robustly stable dynamics which is always present and is neither tolerance nor immunity-a problem currently approached as one of "regulatory" activity. However, a regulatory response also demands regulation, leading to an endless recursion and the adoption of a stimulus-response framework inevitably drives us away from the physiological processes in which lymphocytes are involved. Herein, we propose that immunological physiology, like everything else in the body is dynamic and conservative. Immunopathology, including inherited immunodeficiencies, severe forms of infectious diseases, allergy and autoimmune diseases, are interferences with this stability which frequently include oligoclonal expansions of T lymphocytes. We suggest that this decrease in clonal diversity results from a loss of the stabilizing connectivity among lymphocytes and are not simply markers of immunopathology, but are rather expressions of basic pathogenic mechanisms. The so-called autoimmune diseases are examples of this disequilibrium. In the last decade the characterization of an enormous and diversified commensal microbiota has posed a new and pressing problem: how to explain the harmonic conviviality with trillions of foreign macromolecules. In addition, robustly stable relations towards macromolecular diet can be established by simple ingestion, a state presently labeled as "oral tolerance", a problem that has been buffered for decades as anti-inflammatory protection of the gut. A major change in terminology is necessary

  18. Congenital Viral Infections of the Brain: Lessons Learned from Lymphocytic Choriomeningitis Virus in the Neonatal Rat

    PubMed Central

    Bonthius, Daniel J; Perlman, Stanley

    2007-01-01

    -onset neuronal loss after the virus has been cleared, the neonatal rat infected with LCMV may be an excellent model system to study neurodegenerative or psychiatric diseases whose etiologies are hypothesized to be virus-induced, such as autism, schizophrenia, and temporal lobe epilepsy. PMID:18052527

  19. Virus-induced gene complementation in tomato

    PubMed Central

    Kong, Jinhua; Chen, Weiwei; Shen, Jiajia; Qin, Cheng; Lai, Tongfei; Zhang, Pengcheng; Wang, Ying; Wu, Chaoqun; Yang, Xin; Hong, Yiguo

    2013-01-01

    Virus-induced gene complementation (VIGC), a plant virus technology based on Potato virus X for transient overexpression of endogenous genes complemented tomato mutants, resulting in non-ripening fruits to ripen. This efficient “gain-of-function” approach involves no stable transformation, and reveals a fruit-specific transcriptional network that may exist among key transcription factors in modulating tomato ripening. Thus, VIGC represents a novel and feasible strategy for gene functional analysis in plants. PMID:24305652

  20. Inhibition of diacylglycerol kinase α restores restimulation-induced cell death and reduces immunopathology in XLP-1.

    PubMed

    Ruffo, Elisa; Malacarne, Valeria; Larsen, Sasha E; Das, Rupali; Patrussi, Laura; Wülfing, Christoph; Biskup, Christoph; Kapnick, Senta M; Verbist, Katherine; Tedrick, Paige; Schwartzberg, Pamela L; Baldari, Cosima T; Rubio, Ignacio; Nichols, Kim E; Snow, Andrew L; Baldanzi, Gianluca; Graziani, Andrea

    2016-01-13

    X-linked lymphoproliferative disease (XLP-1) is an often-fatal primary immunodeficiency associated with the exuberant expansion of activated CD8(+) T cells after Epstein-Barr virus (EBV) infection. XLP-1 is caused by defects in signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), an adaptor protein that modulates T cell receptor (TCR)-induced signaling. SAP-deficient T cells exhibit impaired TCR restimulation-induced cell death (RICD) and diminished TCR-induced inhibition of diacylglycerol kinase α (DGKα), leading to increased diacylglycerol metabolism and decreased signaling through Ras and PKCθ (protein kinase Cθ). We show that down-regulation of DGKα activity in SAP-deficient T cells restores diacylglycerol signaling at the immune synapse and rescues RICD via induction of the proapoptotic proteins NUR77 and NOR1. Pharmacological inhibition of DGKα prevents the excessive CD8(+) T cell expansion and interferon-γ production that occur in SAP-deficient mice after lymphocytic choriomeningitis virus infection without impairing lytic activity. Collectively, these data highlight DGKα as a viable therapeutic target to reverse the life-threatening EBV-associated immunopathology that occurs in XLP-1 patients. PMID:26764158

  1. Immunopathology of chronic lentivirus-induced arthritis.

    PubMed Central

    Wilkerson, M. J.; Davis, W. C.; Baszler, T. V.; Cheevers, W. P.

    1995-01-01

    This study evaluated histopathology and mononuclear cell phenotypes in synovial lesions of chronic arthritis induced by experimental infection of Saanen goats with caprine arthritis-encephalitis lentivirus. Histological examination of carpal joint synovium of three infected goats with clinical arthritis revealed progressive lesions consisting of membrane villus hypertrophy with extensive angiogenesis and mononuclear cell infiltration and degenerative changes of membrane villus necrosis associated with loss of vasculature and infiltrates. Changes in synovial tissue of five age-matched infected goats without clinical arthritis were limited to moderate synovial membrane hyperplasia also noted in an age-matched uninfected goat. Immunohistochemistry identified CD45R+ CD5- B lymphocytes as the principal component of most perivascular infiltrates in arthritic synovium. Other mononuclear cells included perivascular CD4+ and CD8+ T lymphocytes and macrophages with a prominent accumulation of CD8+ T lymphocytes at the lining surface of inflamed villi. T lymphocytes and macrophages as well as synovial lining cells were activated with respect to MHC class II but not for interleukin-2 receptors. Inflamed villi also contained lymphoid aggregates comprised of B cell germinal centers and activated T-cell mantles. B cells expressing immunoglobulin occurred around follicles and throughout inflamed villi. These findings indicate that memory immune responses that favor expansion and maturation of B cells and immunoglobulin production contribute to the immunopathology of chronic arthritis. Images Figure 1 Figure 2 Figure 3 Figure 5 Figure 6 PMID:7778682

  2. Trace-Forward Investigation of Mice in Response to Lymphocytic Choriomeningitis Virus Outbreak

    PubMed Central

    Knust, Barbara; Petersen, Bret; Gabel, Julie; Manning, Craig; Drenzek, Cherie; Ströher, Ute; Rollin, Pierre E.; Thoroughman, Douglas; Nichol, Stuart T.

    2014-01-01

    During follow-up of a 2012 US outbreak of lymphocytic choriomeningitis virus (LCMV), we conducted a trace-forward investigation. LCMV-infected feeder mice originating from a US rodent breeding facility had been distributed to >500 locations in 21 states. All mice from the facility were euthanized, and no additional persons tested positive for LCMV infection. PMID:24447898

  3. Expanding the range of immunopathology in neuromyelitis optica spectrum disorder.

    PubMed

    Massey, Jennifer; Buckland, Michael E; Barnett, Yael; Sutton, Ian

    2016-01-01

    Neuromyelitis optica (NMO) spectrum disorder typically associates with a pathognomonic antibody response directed against aquaporin 4 and a unique immunopathological signature characterised by loss of aquaporin 4 expression. We describe a tumefactive presentation of NMO in which a biopsy specimen demonstrated active demyelination and reactive astrocytes with preserved surface aquaporin 4 immunoreactivity and dystrophic processes. While the astrocytic pathology is more typical of classical multiple sclerosis, a positive NMO-IgG (1:80) and subsequent clinical presentation with an area postrema syndrome is consistent with a diagnosis of NMO spectrum disorder. This report expands the immunopathological features that have been reported in NMO spectrum disorder. PMID:27469383

  4. Isolation and characterization of a new strain of lymphocytic choriomeningitis virus from rodents in southwestern France.

    PubMed

    Yama, Ines N; Cazaux, Benoite; Britton-Davidian, Janice; Moureau, Grégory; Thirion, Laurence; de Lamballerie, Xavier; Dobigny, Gauthier; Charrel, Rémi N

    2012-10-01

    A total of 821 tissue samples from rodents trapped during field campaigns organized in Europe and Africa were screened for the presence of arenaviruses by molecular methods and cell culture inoculation when feasible. Two Mus musculus domesticus trapped in the southwestern part of France were infected with a potentially new strain of lymphocytic choriomeningitis virus (LCMV), here referred to as LCMV strain HP65-2009, which was isolated and genetically characterized by whole genome sequencing. Genetic and phylogenetic analyses comparing LCMV HP65-2009 with 26 other LCMV strains showed that it represents a novel highly-divergent strain within the group of Mus musculus-associated LCMV. PMID:22651393

  5. Newly Described Clinical and Immunopathological Feature of Dermatitis Herpetiformis

    PubMed Central

    Bonciolini, Veronica; Bonciani, Diletta; Verdelli, Alice; D'Errico, Antonietta; Antiga, Emiliano; Fabbri, Paolo; Caproni, Marzia

    2012-01-01

    Dermatitis herpetiformis (DH) is an inflammatory cutaneous disease with typical histopathological and immunopathological findings clinically characterized by intensely pruritic polymorphic lesions with a chronic-relapsing course. In addition to classic clinical manifestations of DH, atypical variants are more and more frequently reported and histological and immunological are added to them, whereas the impact on quality of life of patients with DH is increasingly important to a certain diagnosis. The aim of this paper is to describe all the possible clinical, histological, and immunological variants of DH in order to facilitate the diagnosis of a rare disease and, therefore, little known. PMID:22701503

  6. Virus-induced gene silencing (VIGS) in barley seedling leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-induced gene silencing (VIGS) is one of the most potent reverse genetics technologies for gene functional characterization. This method exploits a dsRNA-mediated antiviral defense mechanism in plants. Using this method allows researchers to generate rapid phenotypic data in a relatively rapid ...

  7. Measles Virus Induces Functional TRAIL Production by Human Dendritic Cells

    PubMed Central

    Vidalain, Pierre-Olivier; Azocar, Olga; Lamouille, Barbara; Astier, Anne; Rabourdin-Combe, Chantal; Servet-Delprat, Christine

    2000-01-01

    Measles virus infection induces a profound immunosuppression that can lead to serious secondary infections. Here we demonstrate that measles virus induces tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) mRNA and protein expression in human monocyte-derived dendritic cells. Moreover, measles virus-infected dendritic cells are shown to be cytotoxic via the TRAIL pathway. PMID:10590149

  8. Virus-Induced Gene Silencing in Hexaploid Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional genomics analysis in hexaploid wheat is greatly impeded by the genetic redundancy of polyploidy and the difficulties in generating large numbers of transgenic plants required in insertional mutagenesis strategies. Virus-induced gene silencing (VIGS), however, is a strategy for creating g...

  9. Virus-Induced Gene Silencing in Ornametal Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-Induced Gene Silencing (VIGS) provides an attractive tool for high throughput analysis of the functional effects of gene knock-down. Virus genomes are engineered to include fragments of target host genes, and the infected plant recognizes and silences the target genes as part of its viral defe...

  10. Virus-Induced gene silencing in ornamental plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-Induced Gene Silencing (VIGS) provides an attractive tool for high throughput analysis of the functional effects of gene knock-down. Virus genomes are engineered to include fragments of target host genes, and the infected plant recognizes and silences the target genes as part of its viral defe...

  11. Lymphocytic Choriomeningitis Virus in Employees and Mice at Multipremises Feeder-Rodent Operation, United States, 2012

    PubMed Central

    Ströher, Ute; Edison, Laura; Albariño, César G.; Lovejoy, Jodi; Armeanu, Emilian; House, Jennifer; Cory, Denise; Horton, Clayton; Fowler, Kathy L.; Austin, Jessica; Poe, John; Humbaugh, Kraig E.; Guerrero, Lisa; Campbell, Shelley; Gibbons, Aridth; Reed, Zachary; Cannon, Deborah; Manning, Craig; Petersen, Brett; Metcalf, Douglas; Marsh, Bret; Nichol, Stuart T.; Rollin, Pierre E.

    2014-01-01

    We investigated the extent of lymphocytic choriomeningitis virus (LCMV) infection in employees and rodents at 3 commercial breeding facilities. Of 97 employees tested, 31 (32%) had IgM and/or IgG to LCMV, and aseptic meningitis was diagnosed in 4 employees. Of 1,820 rodents tested in 1 facility, 382 (21%) mice (Mus musculus) had detectable IgG, and 13 (0.7%) were positive by reverse transcription PCR; LCMV was isolated from 8. Rats (Rattus norvegicus) were not found to be infected. S-segment RNA sequence was similar to strains previously isolated in North America. Contact by wild mice with colony mice was the likely source for LCMV, and shipments of infected mice among facilities spread the infection. The breeding colonies were depopulated to prevent further human infections. Future outbreaks can be prevented with monitoring and management, and employees should be made aware of LCMV risks and prevention. PMID:24447605

  12. SHP-1-dependent macrophage differentiation exacerbates virus-induced myositis

    PubMed Central

    Watson, Neva B.; Schneider, Karin M.; Massa, Paul T.

    2015-01-01

    Virus-induced myositis is an emerging global affliction that remains poorly characterized with few treatment options. Moreover, muscle-tropic viruses often spread to the central nervous system causing dramatically increased morbidity. Therefore, there is an urgent need to explore genetic factors involved in this class of human disease. This report investigates critical innate immune pathways affecting murine virus-induced myositis. Of particular importance, the key immune regulator SHP-1, which normally suppresses macrophage-mediated inflammation, is a major factor in promoting clinical disease in muscle. We show that Theiler’s murine encephalomyelitis virus infection of skeletal myofibers induces inflammation and subsequent dystrophic calcification with loss of ambulation in wild type mice. Surprisingly, although similar extensive myofiber infection and inflammation is observed in SHP-1-deficient (SHP-1−/−) mice, these mice neither accumulate dead calcified myofibers nor lose ambulation. Macrophages were the predominant effector cells infiltrating WT and SHP-1−/− muscle, and an increased infiltration of immature monocytes/macrophages correlated with absence of clinical disease in SHP-1−/− mice, while mature M1-like macrophages corresponded with increased myofiber degeneration in WT mice. Furthermore, blocking SHP-1 activation in WT macrophages blocked virus-induced myofiber degeneration, and pharmacologic ablation of macrophages inhibited muscle calcification in TMEV-infected WT animals. These data suggest that following TMEV infection of muscle, SHP-1 promotes M1 differentiation of infiltrating macrophages, and these inflammatory macrophages are likely involved in damaging muscle fibers. These findings reveal a pathological role for SHP-1 in promoting inflammatory macrophage differentiation and myofiber damage in virus-infected skeletal muscle, thus identifying SHP-1 and M1 macrophages as essential mediators of virus-induced myopathy. PMID:25681345

  13. Experimental Models of Microvascular Immunopathology: The Example of Cerebral Malaria

    PubMed Central

    El-Assaad, Fatima; Combes, Valery; Grau, Georges ER

    2015-01-01

    Human cerebral malaria is a severe and often lethal complication of Plasmodium falciparum infection. Complex host and parasite interactions should the precise mechanisms involved in the onset of this neuropathology. Adhesion of parasitised red blood cells and host cells to endothelial cells lead to profound endothelial alterations that trigger immunopathological changes, varying degrees of brain oedema and can compromise cerebral blood flow, cause cranial nerve dysfunction and hypoxia. Study of the cerebral pathology in human patients is limited to clinical and genetic field studies in endemic areas, thus cerebral malaria (CM) research relies heavily on experimental models. The availability of malaria models allows study from the inoculation of Plasmodium to the onset of disease and permit invasive experiments. Here, we discuss some aspects of our current understanding of CM, the experimental models available and some important recent findings extrapolated from these models. PMID:26430675

  14. Pulmonary immunity and immunopathology: lessons from respiratory syncytial virus

    PubMed Central

    Olson, Matthew R; Varga, Steven M

    2009-01-01

    Respiratory syncytial virus (RSV) is the leading cause of severe respiratory disease in infants and is an important source of morbidity and mortality in the elderly and immunocompromised. This review will discuss the humoral and cellular adaptive immune responses to RSV infection and how these responses are shaped in the immature immune system of the infant and the aged environment of the elderly. Furthermore, we will provide an overview of our current understanding of the role the various arms of the adaptive immune response play in mediating the delicate balance between the successful elimination of the virus from the host and the induction of immunopathology. Efficacious immunization against RSV remains a high priority within the field and we will highlight recent advances made in vaccine design. PMID:18844597

  15. The immunopathology of canine vector-borne diseases

    PubMed Central

    2011-01-01

    The canine vector-borne infectious diseases (CVBDs) are an emerging problem in veterinary medicine and the zoonotic potential of many of these agents is a significant consideration for human health. The successful diagnosis, treatment and prevention of these infections is dependent upon firm understanding of the underlying immunopathology of the diseases in which there are unique tripartite interactions between the microorganism, the vector and the host immune system. Although significant advances have been made in the areas of molecular speciation and the epidemiology of these infections and their vectors, basic knowledge of the pathology and immunology of the diseases has lagged behind. This review summarizes recent studies of the pathology and host immune response in the major CVBDs (leishmaniosis, babesiosis, ehrlichiosis, hepatozoonosis, anaplasmosis, bartonellosis and borreliosis). The ultimate application of such immunological investigation is the development of effective vaccines. The current commercially available vaccines for canine leishmaniosis, babesiosis and borreliosis are reviewed. PMID:21489234

  16. Immunobiology of cytotoxic T-cell escape mutants of lymphocytic choriomeningitis virus.

    PubMed Central

    Moskophidis, D; Zinkernagel, R M

    1995-01-01

    Infection with virus variants exhibiting changes in the peptide sequences defining immunodominant determinants that abolish recognition by antiviral cytotoxic T cells (CTL) presents a considerable challenge to the antiviral T-cell immune system and may enable some viruses to persist in hosts. The potential importance of such variants with respect to mechanisms of viral persistence and disease pathogenesis was assessed by infecting adult mice with variants of lymphocytic choriomeningitis virus (LCMV) strain WE. These variants were selected in vivo or in vitro for resistance to lysis by CD8+ H-2b-restricted antiviral CTL. The majority of anti-LCMV CTL in infected H-2b mice recognize epitopes defined by residues 32 to 42 and 275 to 289 (epitopes 32-42 and 275-289) of the LCMV glycoprotein or 397 to 407 of the viral nucleoprotein. The 8.7 variant exhibits a change in the epitope 32-42 (Val-35-->Leu), and variant CL1.2 exhibits a change in the epitope 275-289 (Asn-280-->Asp) of the wild-type LCMV-WE. The double-mutated 8.7-B23 variant had the variation of 8.7 and an additional change located in the epitope 275-289 (Asn-280-->Ser). The 8.7 variant peptide with unchanged anchor positions bound efficiently to H-2Db and H-2Kb molecules but induced only a very weak CTL response. CTL epitope 275-289 of CL1.2 and 8.7-B23 altered at predicted anchor residues were unable to bind Db molecules and were also not recognized by antiviral CTL. Infection of C57BL/6 mice (H-2b) with the variants exhibiting mutations of one of the CTL epitopes, i.e., 8.7 or CL1.2, induced CTL responses specific for the unmutated epitopes comparable with those induced by infection with WE, and these responses were sufficient to eliminate virus from the host. In contrast, infection with the double-mutated variant 8.7-B23 induced CTL activity that was reduced by a factor of about 50-fold compared with wild-type LCMV. Consequently, high doses (10(7) PFU intravenously) of this virus were eliminated slowly and

  17. The Role of Myeloid Cell Activation and Arginine Metabolism in the Pathogenesis of Virus-Induced Diseases

    PubMed Central

    Burrack, Kristina S.; Morrison, Thomas E.

    2014-01-01

    When an antiviral immune response is generated, a balance must be reached between two opposing pathways: the production of proinflammatory and cytotoxic effectors that drive a robust antiviral immune response to control the infection and regulators that function to limit or blunt an excessive immune response to minimize immune-mediated pathology and repair tissue damage. Myeloid cells, including monocytes and macrophages, play an important role in this balance, particularly through the activities of the arginine-hydrolyzing enzymes nitric oxide synthase 2 (Nos2; iNOS) and arginase 1 (Arg1). Nitric oxide (NO) production by iNOS is an important proinflammatory mediator, whereas Arg1-expressing macrophages contribute to the resolution of inflammation and wound repair. In the context of viral infections, expression of these enzymes can result in a variety of outcomes for the host. NO has direct antiviral properties against some viruses, whereas during other virus infections NO can mediate immunopathology and/or inhibit the antiviral immune response to promote chronic infection. Arg1 activity not only has important wound healing functions but can also inhibit the antiviral immune response during some viral infections. Thus, depending on the specific virus and the tissue(s) involved, the activity of both of these arginine-hydrolyzing enzymes can either exacerbate or limit the severity of virus-induced disease. In this review, we will discuss a variety of viral infections, including HIV, SARS-CoV, LCMV, HCV, RSV, and others, where myeloid cells influence the control and clearance of the virus from the host, as well as the severity and resolution of tissue damage, via the activities of iNOS and/or Arg1. Clearly, monocyte/macrophage activation and arginine metabolism will continue to be important areas of investigation in the context of viral infections. PMID:25250029

  18. Epidemiology of virus-induced asthma exacerbations: with special reference to the role of human rhinovirus

    PubMed Central

    Saraya, Takeshi; Kurai, Daisuke; Ishii, Haruyuki; Ito, Anri; Sasaki, Yoshiko; Niwa, Shoichi; Kiyota, Naoko; Tsukagoshi, Hiroyuki; Kozawa, Kunihisa; Goto, Hajime; Takizawa, Hajime

    2014-01-01

    Viral respiratory infections may be associated with the virus-induced asthma in adults as well as children. Particularly, human rhinovirus is strongly suggested a major candidate for the associations of the virus-induced asthma. Thus, in this review, we reviewed and focused on the epidemiology, pathophysiology, and treatment of virus-induced asthma with special reference on human rhinovirus. Furthermore, we added our preliminary data regarding the clinical and virological findings in the present review. PMID:24904541

  19. Peptide motif analysis predicts lymphocytic choriomeningitis virus as trigger for multiple sclerosis.

    PubMed

    Hogeboom, Charissa

    2015-10-01

    The etiology of multiple sclerosis (MS) involves both genetic and environmental factors. Genetically, the strongest link is with HLA DRB1*1501, but the environmental trigger, probably a virus, remains uncertain. This investigation scans a panel of proteins from encephalitogenic viruses for peptides homologous to the primary autoantigen from myelin basic protein (MBP), then evaluates candidate peptides against a motif required for T cell cross-reactivity and compares viral prevalence patterns to epidemiological characteristics of MS. The only peptide meeting criteria for cross-reactivity with MBP was one from lymphocytic choriomeningitis virus (LCMV), a zoonotic agent. In contrast to current candidates such as Epstein-Barr virus, the distribution of LCMV is consistent with epidemiological features of MS, including concentration in the temperate zone, higher prevalence farther from the equator, and increased prevalence in proximity to regions of peak MS incidence, while lack of person-to-person transmission is consistent with low MS concordance across monozygotic twins. Further, LCMV blocks induction of type I interferon (IFN). Hypothetically this would dysregulate immune processes in favor of proinflammatory pathways as well as upregulating HLA class II and providing more binding sites for autoantigen. The combination of molecular mimicry with virally-induced immune dysregulation has the potential to explain aspects of autoimmunity not addressed by either mechanism alone. PMID:26319106

  20. Lymphocytic choriomeningitis virus uses a novel endocytic pathway for infectious entry via late endosomes

    SciTech Connect

    Quirin, Katharina; Eschli, Bruno; Scheu, Isabella; Poort, Linda; Kartenbeck, Juergen; Helenius, Ari

    2008-08-15

    The endocytic entry of lymphocytic choriomeningitis virus (LCMV) into host cells was compared to the entry of viruses known to exploit clathrin or caveolae/raft-dependent pathways. Pharmacological inhibitors, expression of pathway-specific dominant-negative constructs, and siRNA silencing of clathrin together with electron and light microscopy provided evidence that although a minority population followed a classical clathrin-mediated mechanism of entry, the majority of these enveloped RNA viruses used a novel endocytic route to late endosomes. The pathway was clathrin, dynamin-2, actin, Arf6, flotillin-1, caveolae, and lipid raft independent but required membrane cholesterol. Unaffected by perturbation of Rab5 or Rab7 and apparently without passing through Rab5/EEA1-positive early endosomes, the viruses reached late endosomes and underwent acid-induced penetration. This membrane trafficking route between the plasma membrane and late endosomes may function in the turnover of a select group of surface glycoproteins such as the dystroglycan complex, which serves as the receptor of LCMV.

  1. Lymphocytic choriomeningitis virus (LCMV) infection of macaques: a model for Lassa fever.

    PubMed

    Zapata, Juan C; Pauza, C David; Djavani, Mahmoud M; Rodas, Juan D; Moshkoff, Dmitry; Bryant, Joseph; Ateh, Eugene; Garcia, Cybele; Lukashevich, Igor S; Salvato, Maria S

    2011-11-01

    Arenaviruses such as Lassa fever virus (LASV) and lymphocytic choriomeningitis virus (LCMV) are benign in their natural reservoir hosts, and can occasionally cause severe viral hemorrhagic fever (VHF) in non-human primates and in human beings. LCMV is considerably more benign for human beings than Lassa virus, however certain strains, like the LCMV-WE strain, can cause severe disease when the virus is delivered as a high-dose inoculum. Here we describe a rhesus macaque model for Lassa fever that employs a virulent strain of LCMV. Since LASV must be studied within Biosafety Level-4 (BSL-4) facilities, the LCMV-infected macaque model has the advantage that it can be used at BSL-3. LCMV-induced disease is rarely as severe as other VHF, but it is similar in cases where vascular leakage leads to lethal systemic failure. The LCMV-infected macaque has been valuable for describing the course of disease with differing viral strains, doses and routes of infection. By monitoring system-wide changes in physiology and gene expression in a controlled experimental setting, it is possible to identify events that are pathognomonic for developing VHF and potential treatment targets. PMID:21820469

  2. Lymphocytic choriomeningitis virus (LCMV) infection of macaques: a model for Lassa fever

    PubMed Central

    Zapata, Juan C.; Pauza, C. David; Djavani, Mahmoud M.; Rodas, Juan D.; Moshkoff, Dmitry; Bryant, Joseph; Ateh, Eugene; Garcia, Cybele; Lukashevich, Igor S.; Salvato, Maria S.

    2011-01-01

    Arenaviruses such as Lassa fever virus (LASV) and lymphocytic choriomeningitis virus (LCMV) are benign in their natural reservoir hosts, and can occasionally cause severe viral hemorrhagic fever (VHF) in non-human primates and in human beings. LCMV is considerably more benign for human beings than Lassa virus, however certain strains, like the LCMV-WE strain, can cause severe disease when the virus is delivered as a high-dose inoculum. Here we describe a rhesus macaque model for Lassa fever that employs a virulent strain of LCMV. Since LASV must be studied within Biosafety Level-4 (BSL-4) facilities, the LCMV-infected macaque model has the advantage that it can be used at BSL-3. LCMV-induced disease is rarely as severe as other VHF, but it is similar in cases where vascular leakage leads to lethal systemic failure. The LCMV-infected macaque has been valuable for describing the course of disease with differing viral strains, doses and routes of infection. By monitoring system-wide changes in physiology and gene expression in a controlled experimental setting, it is possible to identify events that are pathognomonic for developing VHF and potential treatment targets. PMID:21820469

  3. Wolbachia and its implications for the immunopathology of filariasis.

    PubMed

    Genchi, Claudio; Kramer, Laura H; Sassera, Davide; Bandi, Claudio

    2012-03-01

    Filarial infections are characterized by immunopathological phenomena, that are responsible for the onset of often dramatic pathological outcomes, such as blindness (Onchocerca volvulus) and elephantiasis (W. bancrofti). In addition, the long-term survival (as long as 10 years) of these parasites in otherwise immunocompetent hosts indicates that these nematodes are capable of manipulating the host immune response. The ground-breaking discovery of the bacterial endosymbiont Wolbachia, which resides in most filarial nematodes causing disease, has led to increasing interest in the role it may play in immuno-modulation, pro-inflammatory pathology and other aspects of filarial infection. Indeed, Wolbachia has been shown to be responsible for exacerbating inflammation (as in river blindness), while at the same time blocking efficient elimination of parasites through the host immune response (Onchocerca ochengi). While studies aimed at identifying Wolbachia as a potential target for anti-filarial therapy are at the forefront of current research, understanding its role in the immunology of filarial infection is a fascinating field that has yet to uncover many secrets. PMID:22214329

  4. The immuno-pathological conversions of canine demodicosis.

    PubMed

    Singh, Shanker K; Dimri, Umesh

    2014-06-16

    Canine demodicosis is a common but exigent noncontagious parasitic dermatosis caused by overpopulation of the host-specific follicular mites of various Demodex species. Receptivity of dogs to demodicosis and progression of the clinical disease are influenced by numerous factors including; genetic defect, alteration of skin's structure and biochemistry, immunological disorders, hormonal status, breed, age, nutritional status, oxidative stress, length of hair coat, stage of oestrus cycle, parturition, endoparasitism and debilitating diseases. Of these, the immune status is thought to be the most significant. Thus, in the present review we intended to edify the immuno-pathological conversions of canine demodicosis. Generalized demodicosis requires a cutaneous environment that is ecologically and immunologically favorable for extreme colonization of demodectic mites. Demodex canis mites can down regulate the CD4+ T cells; possibly by an increased rate of apoptosis or immunological exhaustion of CD4+ T cells. An increased apoptosis of peripheral leukocytes confers progression of the clinical manifestations. Mites induced elevation of TGF-β and inhibition of TNF-α mRNA expression might be a key factor for revealing the difference in the mechanism of onset between localized and generalized demodicosis. Moreover, an elevated serum level of IL-10 could be accountable for the recurrence as well as occurrence of demodicosis in dogs. Over production of reactive oxygen species can corroborate immunological discrepancies in dogs with demodicosis. PMID:24680602

  5. Immunopathological Features of Canine Myocarditis Associated with Leishmania infantum Infection

    PubMed Central

    Piegari, Giuseppe; Otrocka-Domagala, Iwona; Ciccarelli, Davide; Iovane, Valentina; Oliva, Gaetano; Russo, Valeria; Rinaldi, Laura; Papparella, Serenella; Paciello, Orlando

    2016-01-01

    Myocarditis associated with infectious diseases may occur in dogs, including those caused by the protozoa Neospora caninum, Trypanosoma cruzi, Babesia canis, and Hepatozoon canis. However, although cardiac disease due to Leishmania infection has also been documented, the immunopathological features of myocarditis have not been reported so far. The aim of this study was to examine the types of cellular infiltrates and expression of MHC classes I and II in myocardial samples obtained at necropsy from 15 dogs with an established intravitam diagnosis of visceral leishmaniasis. Pathological features of myocardium were characterized by hyaline degeneration of cardiomyocytes, necrosis, and infiltration of mononuclear inflammatory cells consisting of lymphocytes and macrophages, sometimes with perivascular pattern; fibrosis was also present in various degrees. Immunophenotyping of inflammatory cells was performed by immunohistochemistry on cryostat sections obtained from the heart of the infected dogs. The predominant leukocyte population was CD8+ with a fewer number of CD4+ cells. Many cardiomyocytes expressed MHC classes I and II on the sarcolemma. Leishmania amastigote forms were not detected within macrophages or any other cell of the examined samples. Our study provided evidence that myocarditis in canine visceral leishmaniasis might be related to immunological alterations associated with Leishmania infection. PMID:27413751

  6. Chemokine gene expression in the brains of mice with lymphocytic choriomeningitis.

    PubMed Central

    Asensio, V C; Campbell, I L

    1997-01-01

    Chemokines are pivotal in the trafficking of leukocytes. In the present study, we examined the expression of multiple chemokine genes during the course of lymphocytic choriomeningitis (LCM) in mice. In noninfected mice, no detectable chemokine gene expression was found in the brain; however, by day 3 postinfection, the induction of a number of chemokine mRNAs was observed as follows (in order from the greatest to the least): cytokine responsive gene-2 or interferon-inducible 10-kDa protein (Crg-2/IP-10), RANTES, monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1 (MIP-1beta), and MCP-3. At day 6 postinfection, the expression of these chemokine mRNAs was increased, and low expression of lymphotactin, C10, MIP-2, and MIP-1alpha mRNAs was detectable. Transcript for T-cell activation-3 was not detectable in the brain at any time following LCM virus (LCMV) infection. With some exceptions, a pattern of chemokine gene expression similar to that in the brain was observed in the peripheral organs of LCMV-infected mice. Mice that lacked expression of gamma interferon developed LCM and had a qualitatively similar but quantitatively reduced cerebral chemokine gene expression profile. In contrast, little or no chemokine gene expression was detectable in the brains of LCMV-infected athymic mice which did not develop LCM. Expression of Crg-2/IP-10 RNA was localized to predominantly resident cells of the central nervous system (CNS) and overlapped with sites of viral infection and immune cell infiltration. These findings demonstrate the expression of a number of chemokine genes in the brains of mice infected with LCMV. The pattern of chemokine gene expression in LCM may profoundly influence the characteristic phenotype and response of leukocytes in the brain and contribute to the immunopathogenesis of this fatal CNS infection. PMID:9311871

  7. Quantity and Quality of Inhaled Dose Predicts Immunopathology in Tuberculosis

    PubMed Central

    Fennelly, Kevin P.; Jones-López, Edward C.

    2015-01-01

    Experimental animal models of tuberculosis (TB) have convincingly demonstrated that inhaled dose predicts immunopathology and survival. In contrast, the importance of inhaled dose has generally not been appreciated in TB epidemiology, clinical science, or the practice of TB control. Infectiousness of TB patients has traditionally been assessed using microscopy for acid-fast bacilli in the sputum, which should be considered only a risk factor. We have recently demonstrated that cough aerosol cultures from index cases with pulmonary TB are the best predictors of new infection among household contacts. We suggest that cough aerosols of M. tuberculosis are the best surrogates of inhaled dose, and we hypothesize that the quantity of cough aerosols is associated with TB infection versus disease. Although several factors affect the quality of infectious aerosols, we propose that the particle size distribution of cough aerosols is an important predictor of primary upper airway disease and cervical lymphadenitis and of immune responses in exposed hosts. We hypothesize that large droplet aerosols (>5 μ) containing M. tuberculosis deposit in the upper airway and can induce immune responses without establishing infection. We suggest that this may partially explain the large proportion of humans who never develop TB disease in spite of having immunological evidence of M. tuberculosis infection (e.g., positive tuberculin skin test or interferon gamma release assay). If these hypotheses are proven true, they would alter the current paradigm of latent TB infection and reactivation, further demonstrating the need for better biomarkers or methods of assessing TB infection and the risk of developing disease. PMID:26175730

  8. Virus -induced plankton dynamic and sea spray oragnics

    NASA Astrophysics Data System (ADS)

    Facchini, Maria Cristina; O'Dowd, Colin; Danovaro, Roberto

    2015-04-01

    The processes that link phytoplankton biomass and productivity to the organic matter enrichment in sea spray aerosol are far from being understood and modelling predictions remain highly uncertain at the moment. While some studies have asserted that the enrichment of OM in sea spray aerosol is independent on marine productivity, others, on the contrary, have shown significant correlation with phytoplankton biomass and productivity (Chl-a retrieved by satellites). Here we show that viral infection of prokaryotes and phytoplankton, by inducing the release of large quantities of surfaceactive organic matter (cell debris, exudates and other colloidal gel-forming material), in part due to cell lysis and plankton defence reactions, and in part from rapid virus multiplication, triggers the organic matter (OM) enrichment in the sea-spray particles during blooms. We show that virus-induced bloom dynamics may explain the contrasting results present in literature on the link between primary productivity and OM sea spray enrichment.

  9. Immunopathology and Cytokine Responses in Commercial Broiler Chickens with Gangrenous Dermatitis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gangrene dermatitis (GD) is an emerging disease of increasing economic importance in poultry that results from infection by Clostridium septicum and C. perfringens (CP) type A. Lack of a reproducible disease model has been a major obstacle in understanding the immunopathology of GD. To gain better u...

  10. TPL-2 Regulates Macrophage Lipid Metabolism and M2 Differentiation to Control TH2-Mediated Immunopathology

    PubMed Central

    Entwistle, Lewis J.; Khoury, Hania; Papoutsopoulou, Stamatia; Mahmood, Radma; Mansour, Nuha R.; Ching-Cheng Huang, Stanley; Pearce, Edward J.; Pedro S. de Carvalho, Luiz; Ley, Steven C.

    2016-01-01

    Persistent TH2 cytokine responses following chronic helminth infections can often lead to the development of tissue pathology and fibrotic scarring. Despite a good understanding of the cellular mechanisms involved in fibrogenesis, there are very few therapeutic options available, highlighting a significant medical need and gap in our understanding of the molecular mechanisms of TH2-mediated immunopathology. In this study, we found that the Map3 kinase, TPL-2 (Map3k8; Cot) regulated TH2-mediated intestinal, hepatic and pulmonary immunopathology following Schistosoma mansoni infection or S. mansoni egg injection. Elevated inflammation, TH2 cell responses and exacerbated fibrosis in Map3k8–/–mice was observed in mice with myeloid cell-specific (LysM) deletion of Map3k8, but not CD4 cell-specific deletion of Map3k8, indicating that TPL-2 regulated myeloid cell function to limit TH2-mediated immunopathology. Transcriptional and metabolic assays of Map3k8–/–M2 macrophages identified that TPL-2 was required for lipolysis, M2 macrophage activation and the expression of a variety of genes involved in immuno-regulatory and pro-fibrotic pathways. Taken together this study identified that TPL-2 regulated TH2-mediated inflammation by supporting lipolysis and M2 macrophage activation, preventing TH2 cell expansion and downstream immunopathology and fibrosis. PMID:27487182

  11. Timed action of IL-27 protects from immunopathology while preserving defense in influenza.

    PubMed

    Liu, Francesca Diane M; Kenngott, Elisabeth E; Schröter, Micha F; Kühl, Anja; Jennrich, Silke; Watzlawick, Ralf; Hoffmann, Ute; Wolff, Thorsten; Norley, Stephen; Scheffold, Alexander; Stumhofer, Jason S; Saris, Christiaan J M; Schwab, Jan M; Hunter, Christopher A; Debes, Gudrun F; Hamann, Alf

    2014-05-01

    Infection with influenza virus can result in massive pulmonary infiltration and potentially fatal immunopathology. Understanding the endogenous mechanisms that control immunopathology could provide a key to novel adjunct therapies for this disease. Here we show that the cytokine IL-27 plays a crucial role in protection from exaggerated inflammation during influenza virus infection. Using Il-27ra-/- mice, IL-27 was found to limit immunopathology, neutrophil accumulation, and dampened TH1 or TH17 responses via IL-10-dependent and -independent pathways. Accordingly, the absence of IL-27 signals resulted in a more severe disease course and in diminished survival without impacting viral loads. Consistent with the delayed expression of endogenous Il-27p28 during influenza, systemic treatment with recombinant IL-27 starting at the peak of virus load resulted in a major amelioration of lung pathology, strongly reduced leukocyte infiltration and improved survival without affecting viral clearance. In contrast, early application of IL-27 impaired virus clearance and worsened disease. These findings demonstrate the importance of IL-27 for the physiological control of immunopathology and the potential value of well-timed IL-27 application to treat life-threatening inflammation during lung infection. PMID:24809349

  12. TPL-2 Regulates Macrophage Lipid Metabolism and M2 Differentiation to Control TH2-Mediated Immunopathology.

    PubMed

    Kannan, Yashaswini; Perez-Lloret, Jimena; Li, Yanda; Entwistle, Lewis J; Khoury, Hania; Papoutsopoulou, Stamatia; Mahmood, Radma; Mansour, Nuha R; Ching-Cheng Huang, Stanley; Pearce, Edward J; Pedro S de Carvalho, Luiz; Ley, Steven C; Wilson, Mark S

    2016-08-01

    Persistent TH2 cytokine responses following chronic helminth infections can often lead to the development of tissue pathology and fibrotic scarring. Despite a good understanding of the cellular mechanisms involved in fibrogenesis, there are very few therapeutic options available, highlighting a significant medical need and gap in our understanding of the molecular mechanisms of TH2-mediated immunopathology. In this study, we found that the Map3 kinase, TPL-2 (Map3k8; Cot) regulated TH2-mediated intestinal, hepatic and pulmonary immunopathology following Schistosoma mansoni infection or S. mansoni egg injection. Elevated inflammation, TH2 cell responses and exacerbated fibrosis in Map3k8-/-mice was observed in mice with myeloid cell-specific (LysM) deletion of Map3k8, but not CD4 cell-specific deletion of Map3k8, indicating that TPL-2 regulated myeloid cell function to limit TH2-mediated immunopathology. Transcriptional and metabolic assays of Map3k8-/-M2 macrophages identified that TPL-2 was required for lipolysis, M2 macrophage activation and the expression of a variety of genes involved in immuno-regulatory and pro-fibrotic pathways. Taken together this study identified that TPL-2 regulated TH2-mediated inflammation by supporting lipolysis and M2 macrophage activation, preventing TH2 cell expansion and downstream immunopathology and fibrosis. PMID:27487182

  13. Efficient Virus-Induced Gene Silencing in Solanum rostratum

    PubMed Central

    Meng, Lan-Huan; Wang, Rui-Heng; Zhu, Ben-Zhong; Zhu, Hong-Liang; Luo, Yun-Bo; Fu, Da-Qi

    2016-01-01

    Solanum rostratum is a “super weed” that grows fast, is widespread, and produces the toxin solanine, which is harmful to both humans and other animals. To our knowledge, no study has focused on its molecular biology owing to the lack of available transgenic methods and sequence information for S. rostratum. Virus-induced gene silencing (VIGS) is a powerful tool for the study of gene function in plants; therefore, in the present study, we aimed to establish tobacco rattle virus (TRV)-derived VIGS in S. rostratum. The genes for phytoene desaturase (PDS) and Chlorophyll H subunit (ChlH) of magnesium protoporphyrin chelatase were cloned from S. rostratum and used as reporters of gene silencing. It was shown that high-efficiency VIGS can be achieved in the leaves, flowers, and fruit of S. rostratum. Moreover, based on our comparison of three different types of infection methods, true leaf infection was found to be more efficient than cotyledon and sprout infiltration in long-term VIGS in multiple plant organs. In conclusion, the VIGS technology and tomato genomic sequences can be used in the future to study gene function in S. rostratum. PMID:27258320

  14. Efficient Virus-Induced Gene Silencing in Solanum rostratum.

    PubMed

    Meng, Lan-Huan; Wang, Rui-Heng; Zhu, Ben-Zhong; Zhu, Hong-Liang; Luo, Yun-Bo; Fu, Da-Qi

    2016-01-01

    Solanum rostratum is a "super weed" that grows fast, is widespread, and produces the toxin solanine, which is harmful to both humans and other animals. To our knowledge, no study has focused on its molecular biology owing to the lack of available transgenic methods and sequence information for S. rostratum. Virus-induced gene silencing (VIGS) is a powerful tool for the study of gene function in plants; therefore, in the present study, we aimed to establish tobacco rattle virus (TRV)-derived VIGS in S. rostratum. The genes for phytoene desaturase (PDS) and Chlorophyll H subunit (ChlH) of magnesium protoporphyrin chelatase were cloned from S. rostratum and used as reporters of gene silencing. It was shown that high-efficiency VIGS can be achieved in the leaves, flowers, and fruit of S. rostratum. Moreover, based on our comparison of three different types of infection methods, true leaf infection was found to be more efficient than cotyledon and sprout infiltration in long-term VIGS in multiple plant organs. In conclusion, the VIGS technology and tomato genomic sequences can be used in the future to study gene function in S. rostratum. PMID:27258320

  15. Vaccinia Virus Induces Programmed Necrosis in Ovarian Cancer Cells

    PubMed Central

    Whilding, Lynsey M; Archibald, Kyra M; Kulbe, Hagen; Balkwill, Frances R; Öberg, Daniel; McNeish, Iain A

    2013-01-01

    The mechanisms by which oncolytic vaccinia virus induces tumor cell death are poorly understood. We have evaluated cell death pathways following infection of ovarian cancer cells with both wild-type and thymidine kinase-deleted (dTK) Lister strain vaccinia. We show that death does not rely upon classical apoptosis despite the appearances of some limited apoptotic features, including phosphatidylserine externalization and appearance of sub-G1 DNA populations. Vaccinia infection induces marked lipidation of LC3 proteins, but there is no general activation of the autophagic process and cell death does not rely upon autophagy induction. We show that vaccinia induces necrotic morphology on transmission electron microscopy, accompanied by marked by reductions in intracellular adenosine triphosphate, altered mitochondrial metabolism, and release of high mobility group box 1 (HMGB1) protein. This necrotic cell death appears regulated, as infection induces formation of a receptor interacting protein (RIP1)/caspase-8 complex. In addition, pharmacological inhibition of both RIP1 and substrates downstream of RIP1, including MLKL, significantly attenuate cell death. Blockade of TNF-α, however, does not alter virus efficacy, suggesting that necrosis does not result from autocrine cytokine release. Overall, these results show that, in ovarian cancer cells, vaccinia virus causes necrotic cell death that is mediated through a programmed series of events. PMID:23985697

  16. Virus-induced gene silencing in eggplant (Solanum melongena).

    PubMed

    Liu, Haiping; Fu, Daqi; Zhu, Benzhong; Yan, Huaxue; Shen, Xiaoying; Zuo, Jinhua; Zhu, Yi; Luo, Yunbo

    2012-06-01

    Eggplant (Solanum melongena) is an economically important vegetable requiring investigation into its various genomic functions. The current limitation in the investigation of genomic function in eggplant is the lack of effective tools available for conducting functional assays. Virus-induced gene silencing (VIGS) has played a critical role in the functional genetic analyses. In this paper, TRV-mediated VIGS was successfully elicited in eggplant. We first cloned the CDS sequence of PDS (PHYTOENE DESATURASE) in eggplant and then silenced the PDS gene. Photo-bleaching was shown on the newly-developed leaves four weeks after agroinoculation, indicating that VIGS can be used to silence genes in eggplant. To further illustrate the reliability of VIGS in eggplant, we selected Chl H, Su and CLA1 as reporters to elicit VIGS using the high-pressure spray method. Suppression of Chl H and Su led to yellow leaves, while the depletion of CLA1 resulted in albino. In conclusion, four genes, PDS, Chl H, Su (Sulfur), CLA1, were down-regulated significantly by VIGS, indicating that the VIGS system can be successfully applied in eggplant and is a reliable tool for the study of gene function. PMID:22268843

  17. Foxtail Mosaic Virus-Induced Gene Silencing in Monocot Plants.

    PubMed

    Liu, Na; Xie, Ke; Jia, Qi; Zhao, Jinping; Chen, Tianyuan; Li, Huangai; Wei, Xiang; Diao, Xianmin; Hong, Yiguo; Liu, Yule

    2016-07-01

    Virus-induced gene silencing (VIGS) is a powerful technique to study gene function in plants. However, very few VIGS vectors are available for monocot plants. Here we report that Foxtail mosaic virus (FoMV) can be engineered as an effective VIGS system to induce efficient silencing of endogenous genes in monocot plants including barley (Hordeum vulgare L.), wheat (Triticum aestivum) and foxtail millet (Setaria italica). This is evidenced by FoMV-based silencing of phytoene desaturase (PDS) and magnesium chelatase in barley, of PDS and Cloroplastos alterados1 in foxtail millet and wheat, and of an additional gene IspH in foxtail millet. Silencing of these genes resulted in photobleached or chlorosis phenotypes in barley, wheat, and foxtail millet. Furthermore, our FoMV-based gene silencing is the first VIGS system reported for foxtail millet, an important C4 model plant. It may provide an efficient toolbox for high-throughput functional genomics in economically important monocot crops. PMID:27225900

  18. Virus-Induced Dormancy in the Archaeon Sulfolobus islandicus

    PubMed Central

    Bautista, Maria A.; Zhang, Changyi

    2015-01-01

    ABSTRACT We investigated the interaction between Sulfolobus spindle-shaped virus (SSV9) and its native archaeal host Sulfolobus islandicus. We show that upon exposure to SSV9, S. islandicus strain RJW002 has a significant growth delay where the majority of cells are dormant (viable but not growing) for 24 to 48 hours postinfection (hpi) compared to the growth of controls without virus. We demonstrate that in this system, dormancy (i) is induced by both active and inactive virus particles at a low multiplicity of infection (MOI), (ii) is reversible in strains with active CRISPR-Cas immunity that prevents the establishment of productive infections, and (iii) results in dramatic and rapid host death if virus persists in the culture even at low levels. Our results add a new dimension to evolutionary models of virus-host interactions, showing that the mere presence of a virus induces host cell stasis and death independent of infection. This novel, highly sensitive, and risky bet-hedging antiviral response must be integrated into models of virus-host interactions in this system so that the true ecological impact of viruses can be predicted and understood. PMID:25827422

  19. Hemorrhagic Fever Occurs After Intravenous, But Not After Intragastric, Inoculation of Rhesus Macaques With Lymphocytic Choriomeningitis Virus

    PubMed Central

    Lukashevich, Igor S.; Djavani, Mahmoud; Rodas, Juan D.; Zapata, Juan C.; Usborne, Amy; Emerson, Carol; Mitchen, Jacque; Jahrling, Peter B.; Salvato, Maria S.

    2008-01-01

    Arenaviruses can cause hemorrhagic fever and death in primates and guinea pigs, but these viruses are not highly pathogenic for most rodent carriers. In the United States, arenaviruses precipitated outbreaks of hepatitis in captive monkeys, and they present an emerging health threat in the tropical areas of Africa and South America. We describe infection of rhesus macaques with the prototype arenavirus, lymphocytic choriome-ningitis virus (LCMV), using the WE strain that has been known to cause both encephalopathy and multifocal hemorrhage. Five macaques were inoculated: two by the intravenous (i.v.) and three by the intragastric (i.g.) route. Whereas the two i.v.-inoculated monkeys developed signs and lesions consistent with fatal hemorrhagic fever, the i.g.-inoculated monkeys had an attenuated infection with no disease. Pathological signs of the primate i.v. infection differ significantly from guinea pig arenavirus infections and make this a superior model for human viral hemorrhagic disease. PMID:11992578

  20. Baculovirus vectors expressing F proteins in combination with virus-induced signaling adaptor (VISA) molecules confer protection against respiratory syncytial virus infection.

    PubMed

    Zhang, Yuan; Qiao, Lei; Hu, Xiao; Zhao, Kang; Zhang, Yanwen; Chai, Feng; Pan, Zishu

    2016-01-01

    Baculovirus has been exploited for use as a novel vaccine vector. To investigate the feasibility and efficacy of recombinant baculoviruses (rBVs) expressing respiratory syncytial virus (RSV) fusion (F) proteins, four constructs (Bac-tF/64, Bac-CF, Bac-CF/tF64 and Bac-CF/tF64-VISA) were generated. Bac-tF64 displays the F ectodomain (tF) on the envelope of rBVs, whereas Bac-CF expresses full-length F protein in transduced mammalian cells. Bac-CF/tF64 not only displays tF on the envelope but also expresses F in cells. Bac-CF/tF64-VISA comprises Bac-CF/tF64 harboring the virus-induced signaling adaptor (VISA) gene. After administration to BALB/c mice, all four vectors elicited RSV neutralizing antibody (Ab), systemic Ab (IgG, IgG1, and IgG2a), and cytokine responses. Compared with Bac-tF64, mice inoculated with Bac-CF and Bac-CF/tF64 exhibited an increased mixed Th1/Th2 cytokine response, increased ratios of IgG2a/IgG1 antibody responses, and reduced immunopathology upon RSV challenge. Intriguingly, co-expression of VISA reduced Th2 cytokine (IL-4, IL-5, and IL-10) production induced by Bac-CF/tF64, thus relieving lung pathology upon a subsequent RSV challenge. Our results indicated that the Bac-CF/tF64 vector incorporated with the VISA molecule may provide an effective vaccine strategy for protection against RSV. PMID:26643933

  1. Nitric oxide controls tuberculosis immunopathology by inhibiting NLRP3 inflammasome-dependent IL-1β processing

    PubMed Central

    Mishra, Bibhuti B.; Rathinam, Vijay A. K.; Martens, Gregory W.; Martinot, Amanda J.; Kornfeld, Hardy; Fitzgerald, Katherine A.; Sassetti, Christopher M.

    2013-01-01

    Interleukin-1 (IL-1) is an important mediator of innate immunity, but can also promote inflammatory tissue damage. During chronic infections, such as tuberculosis, the beneficial antimicrobial role of IL-1 must be balanced with the need to prevent immunopathology. By exogenously controlling the replication of Mycobacterium tuberculosis in vivo, we obviated the requirement for antimicrobial immunity and discovered that both IL-1 production and infection-induced immunopathology were suppressed by lymphocyte-derived interferon-γ (IFN-γ). This effect was mediated by nitric oxide (NO), which we found to specifically inhibit the assembly of the NLRP3 inflammasome via thiol nitrosylation. These data suggest that the NO produced as a result of adaptive immunity is indispensable in modulating the destructive innate inflammatory responses that are elicited during persistent infections. PMID:23160153

  2. Macrophages in Immunopathology of Atherosclerosis: A Target for Diagnostics and Therapy

    PubMed Central

    Orekhov, Alexander N; Sobenin, Igor A; Gavrilin, Mikhail A; Gratchev, Alexei; Kotyashova, Svetlana Y; Nikiforov, Nikita G; Kzhyshkowska, Julia

    2015-01-01

    Immunopathology plays important roles in the development of different life-threatening diseases, such as atherosclerosis and its consequences (acute myocardial infarction and stroke), cancer, chronic inflammatory diseases. Effective modulation of the immune system may significantly increase the efficacy of prevention and therapy efforts. Currently there are no marketed drugs capable of normalizing immune system function in an intrinsic and comprehensive way. Here, we describe a test system designed for complex analysis of monocyte activity in individuals to diagnose immunopathology and monitor treatment efficacy. This cell-based test system may also be useful for screening compounds with an immune-correcting effects. Both diagnostic and screening systems are based on primary culture of human monocytes and/or monocyte-derived macrophages. This is the first step in creating a method for assessment of macrophage activity, which is required for further development of immune-correcting drugs. The existing preliminary data provide the basis for realization of this idea. PMID:25312739

  3. Metabolic regulation of hepatitis B immunopathology by myeloid-derived suppressor cells

    PubMed Central

    Pallett, Laura J.; Gill, Upkar S.; Quaglia, Alberto; Sinclair, Linda V.; Jover-Cobos, Maria; Schurich, Anna; Singh, Kasha P.; Thomas, Niclas; Das, Abhishek; Chen, Antony; Fusai, Giuseppe; Bertoletti, Antonio; Cantrell, Doreen A.; Kennedy, Patrick T.; Davies, Nathan A.; Haniffa, Muzlifah; Maini, Mala K.

    2015-01-01

    Infection with hepatitis B virus (HBV) results in disparate degrees of tissue injury: it can replicate without pathological consequences or trigger immune-mediated necroinflammatory liver damage. We investigated the potential for myeloid-derived suppressor cells (MDSC) to suppress T cell-mediated immunopathology in this setting. Granulocytic MDSC (gMDSC) expanded transiently in acute resolving HBV, decreasing before peak hepatic injury. In persistent infection, arginase-expressing gMDSC (and circulating arginase) increased most in phases characterized by HBV replication without immunopathology, whilst L-arginine decreased. gMDSC expressed liver-homing chemokine receptors and accumulated in the liver, their expansion being supported by hepatic stellate cells. We provide in vitro and ex vivo evidence that gMDSC potently inhibited T cells in a partially arginase-dependent manner. L-arginine-deprived T cells upregulated system-L amino acid transporters to increase uptake of essential nutrients and attempt metabolic reprogramming. These data demonstrate the capacity of expanded arginase-expressing gMDSC to regulate liver immunopathology in HBV infection. PMID:25962123

  4. A plant vacuolar protease, VPE, mediates virus-induced hypersensitive cell death.

    PubMed

    Hatsugai, Noriyuki; Kuroyanagi, Miwa; Yamada, Kenji; Meshi, Tetsuo; Tsuda, Shinya; Kondo, Maki; Nishimura, Mikio; Hara-Nishimura, Ikuko

    2004-08-01

    Programmed cell death (PCD) in animals depends on caspase protease activity. Plants also exhibit PCD, for example as a response to pathogens, although a plant caspase remains elusive. Here we show that vacuolar processing enzyme (VPE) is a protease essential for a virus-induced hypersensitive response that involves PCD. VPE deficiency prevented virus-induced hypersensitive cell death in tobacco plants. VPE is structurally unrelated to caspases, although VPE has a caspase-1 activity. Thus, plants have evolved a regulated cellular suicide strategy that, unlike PCD of animals, is mediated by VPE and the cellular vacuole. PMID:15297671

  5. Inhibition of the Type I Interferon Response by the Nucleoprotein of the Prototypic Arenavirus Lymphocytic Choriomeningitis Virus

    PubMed Central

    Martínez-Sobrido, Luis; Zúñiga, Elina I.; Rosario, Debralee; García-Sastre, Adolfo; de la Torre, Juan Carlos

    2006-01-01

    The prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) is a formidable battle horse for the study of viral immunology, as well as viral persistence and associated diseases. Investigations with LCMV have uncovered basic mechanisms by which viruses avoid elimination by the host adaptive immune response. In this study we show that LCMV also disables the host innate defense by interfering with beta interferon (IFN-β) production in response to different stimuli, including infection with Sendai virus and liposome-mediated DNA transfection. Inhibition of IFN production in LCMV-infected cells was caused by an early block in the IFN regulatory factor 3 (IRF-3) activation pathway. This defect was restored in cells cured of LCMV, indicating that one or more LCMV products are responsible for the inhibition of IRF-3 activation. Using expression plasmids encoding individual LCMV proteins, we found that expression of the LCMV nucleoprotein (NP) was sufficient to inhibit both IFN production and nuclear translocation of IRF-3. To our knowledge, this is the first evidence of an IFN-counteracting viral protein in the Arenaviridae family. Inhibition of IFN production by the arenavirus NP is likely to be a determinant of virulence in vivo. PMID:16940530

  6. Phenotypic and Functional Analysis of Activated Regulatory T Cells Isolated from Chronic Lymphocytic Choriomeningitis Virus-infected Mice.

    PubMed

    Park, Hyo Jin; Oh, Ji Hoon; Ha, Sang-Jun

    2016-01-01

    Regulatory T (Treg) cells, which express Foxp3 as a transcription factor, are subsets of CD4(+) T cells. Treg cells play crucial roles in immune tolerance and homeostasis maintenance by regulating the immune response. The primary role of Treg cells is to suppress the proliferation of effector T (Teff) cells and the production of cytokines such as IFN-γ, TNF-α, and IL-2. It has been demonstrated that Treg cells' ability to inhibit the function of Teff cells is enhanced during persistent pathogen infection and cancer development. To clarify the function of Treg cells under resting or inflamed conditions, a variety of in vitro suppression assays using mouse or human Treg cells have been devised. The main aim of this study is to develop a method to compare the differences in phenotype and suppressive function between resting and activated Treg cells. To isolate activated Treg cells, mice were infected with lymphocytic choriomeningitis virus (LCMV) clone 13 (CL13), a chronic strain of LCMV. Treg cells isolated from the spleen of LCMV CL13-infected mice exhibited both the activated phenotype and enhanced suppressive activity compared with resting Treg cells isolated from naïve mice. Here, we describe the basic protocol for ex vivo phenotype analysis to distinguish activated Treg cells from resting Treg cells. Furthermore, we describe a protocol for the measurement of the suppressive activity of fully activated Treg cells. PMID:27404802

  7. Methods for Virus-Induced Gene Silencing in Hexaploid Wheat using barley stripe mosaic virus vectors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-induced gene silencing (VIGS) is a useful functional genomics tool for rapidly creating gene knockout phenotypes that can be used to infer gene function. Until recently, VIGS has only been possible in dicotyledonous plants. However, the development of vectors based on barley stripe mosaic vi...

  8. Gene expression profiling reveals insight into how distinct viruses induce symptoms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant viruses induce a wide array of disease symptoms and cytopathic effects including alterations of chloroplasts, ribosomes, and cellular architecture. While some of these changes are virus specific, many are common even among diverse viruses, and in most cases, the molecular determinants respons...

  9. Virus induced gene silencing of Arabidopsis gene homologues in wheat identify genes conferring improved drought tolerance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In a non-model staple crop like wheat, functional validation of potential drought stress responsive genes identified in Arabidopsis could provide gene targets for wheat breeding. Virus induced gene silencing (VIGS) of genes of interest can overcome the inherent problems of polyploidy and limited tra...

  10. Co-silencing the mirabilis antiviral protein permits virus-induced gene silencing in Mirabilis jalapa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-induced gene silencing (VIGS) is an attractive and rapid technique for loss of function assay that can reveal the phenotype of embryo-lethal sequences and avoids the need for time consuming transformation and regeneration processes. Among various VIGS vectors that have been explored, the tobac...

  11. Tbet or Continued RORγt Expression Is Not Required for Th17-Associated Immunopathology.

    PubMed

    Brucklacher-Waldert, Verena; Ferreira, Cristina; Innocentin, Silvia; Kamdar, Shraddha; Withers, David R; Kullberg, Marika C; Veldhoen, Marc

    2016-06-15

    The discovery of Th17 cell plasticity, in which CD4(+) IL-17-producing Th17 cells give rise to IL-17/IFN-γ double-producing cells and Th1-like IFNγ(+) ex-Th17 lymphocytes, has raised questions regarding which of these cell types contribute to immunopathology during inflammatory diseases. In this study, we show using Helicobacter hepaticus-induced intestinal inflammation that IL-17A(Cre)- or Rag1(Cre)-mediated deletion of Tbx21 has no effect on the generation of IL-17/IFN-γ double-producing cells, but leads to a marked absence of Th1-like IFNγ(+) ex-Th17 cells. Despite the lack of Th1-like ex-Th17 cells, the degree of H. hepaticus-triggered intestinal inflammation in mice in which Tbx21 was excised in IL-17-producing or Rag1-expressing cells is indistinguishable from that observed in control mice. In stark contrast, using experimental autoimmune encephalomyelitis, we show that IL-17A(Cre)-mediated deletion of Tbx21 prevents the conversion of Th17 cells to IL-17A/IFN-γ double-producing cells as well as Th1-like IFN-γ(+) ex-Th17 cells. However, IL-17A(Cre)-mediated deletion of Tbx21 has only limited effects on disease course in this model and is not compensated by Ag-specific Th1 cells. IL-17A(Cre)-mediated deletion of Rorc reveals that RORγt is essential for the maintenance of the Th17 cell lineage, but not immunopathology during experimental autoimmune encephalomyelitis. These results show that neither the single Th17 subset, nor its progeny, is solely responsible for immunopathology or autoimmunity. PMID:27183623

  12. Tbet or Continued RORγt Expression Is Not Required for Th17-Associated Immunopathology

    PubMed Central

    Brucklacher-Waldert, Verena; Ferreira, Cristina; Innocentin, Silvia; Kamdar, Shraddha; Withers, David R.; Kullberg, Marika C.

    2016-01-01

    The discovery of Th17 cell plasticity, in which CD4+ IL-17–producing Th17 cells give rise to IL-17/IFN-γ double-producing cells and Th1-like IFNγ+ ex-Th17 lymphocytes, has raised questions regarding which of these cell types contribute to immunopathology during inflammatory diseases. In this study, we show using Helicobacter hepaticus-induced intestinal inflammation that IL-17ACre– or Rag1Cre-mediated deletion of Tbx21 has no effect on the generation of IL-17/IFN-γ double-producing cells, but leads to a marked absence of Th1-like IFNγ+ ex-Th17 cells. Despite the lack of Th1-like ex-Th17 cells, the degree of H. hepaticus-triggered intestinal inflammation in mice in which Tbx21 was excised in IL-17–producing or Rag1-expressing cells is indistinguishable from that observed in control mice. In stark contrast, using experimental autoimmune encephalomyelitis, we show that IL-17ACre–mediated deletion of Tbx21 prevents the conversion of Th17 cells to IL-17A/IFN-γ double-producing cells as well as Th1-like IFN-γ+ ex-Th17 cells. However, IL-17ACre–mediated deletion of Tbx21 has only limited effects on disease course in this model and is not compensated by Ag-specific Th1 cells. IL-17ACre–mediated deletion of Rorc reveals that RORγt is essential for the maintenance of the Th17 cell lineage, but not immunopathology during experimental autoimmune encephalomyelitis. These results show that neither the single Th17 subset, nor its progeny, is solely responsible for immunopathology or autoimmunity. PMID:27183623

  13. Thymic stromal lymphopoietin as a novel mediator amplifying immunopathology in rheumatic disease.

    PubMed

    Hillen, Maarten R; Radstake, Timothy R D J; Hack, Cornelis E; van Roon, Joel A G

    2015-10-01

    Thymic stromal lymphopoietin (TSLP) is an IL-7-related cytokine that has been studied extensively in atopic diseases and more recently in various rheumatic disorders. It is involved in T cell development in the thymus and promotes homeostatic T cell expansion by classical dendritic cells. However, deregulated TSLP expression in various rheumatic diseases has implicated this cytokine as a strong mediator in immunopathology. Overexpressed TSLP induces strong T cell activation and production of pro-inflammatory cytokines in human cells and animal models for RA, SSc and LN, underscoring the therapeutic potential of targeting the TSLP-TSLP receptor axis. PMID:26163286

  14. The contribution of the sympathetic nervous system to the immunopathology of experimental pulmonary tuberculosis.

    PubMed

    Barrios-Payán, Jorge; Revuelta, Alberto; Mata-Espinosa, Dulce; Marquina-Castillo, Brenda; Villanueva, Enrique Becerril; Gutiérrez, María Eugenia Hernández; Pérez-Sánchez, Gilberto; Pavón, Lenin; Hernandez-Pando, Rogelio

    2016-09-15

    The role of norepinephrine (NE) in the immunopathology of experimental tuberculosis (TB) was studied by measuring pulmonary NE and determining its cellular sources and targets. Functional studies were performed administrating adrenergic and anti-adrenergic drugs at different TB phases. Results showed high production of NE during early infection by adrenergic nerve terminals and lymphocytes located in the lungs and mediastinal lymph nodes, these cells highly expressed β2 adreno-receptors (β2AR) which by an autocrine mechanism promote Th-1 cell differentiation favoring protection. During advanced infection, the production of NE and β2AR sharply decreased, suggesting that adrenergic activity is less important during late TB. PMID:27609282

  15. Monocyte Activation in Immunopathology: Cellular Test for Development of Diagnostics and Therapy

    PubMed Central

    Ivanova, Ekaterina A.; Orekhov, Alexander N.

    2016-01-01

    Several highly prevalent human diseases are associated with immunopathology. Alterations in the immune system are found in such life-threatening disorders as cancer and atherosclerosis. Monocyte activation followed by macrophage polarization is an important step in normal immune response to pathogens and other relevant stimuli. Depending on the nature of the activation signal, macrophages can acquire pro- or anti-inflammatory phenotypes that are characterized by the expression of distinct patterns of secreted cytokines and surface antigens. This process is disturbed in immunopathologies resulting in abnormal monocyte activation and/or bias of macrophage polarization towards one or the other phenotype. Such alterations could be used as important diagnostic markers and also as possible targets for the development of immunomodulating therapy. Recently developed cellular tests are designed to analyze the phenotype and activity of living cells circulating in patient's bloodstream. Monocyte/macrophage activation test is a successful example of cellular test relevant for atherosclerosis and oncopathology. This test demonstrated changes in macrophage activation in subclinical atherosclerosis and breast cancer and could also be used for screening a panel of natural agents with immunomodulatory activity. Further development of cellular tests will allow broadening the scope of their clinical implication. Such tests may become useful tools for drug research and therapy optimization. PMID:26885534

  16. Host Transcriptional Profiles and Immunopathologic Response following Mycobacterium avium subsp. paratuberculosis Infection in Mice

    PubMed Central

    Shin, Min-Kyoung; Park, Hongtae; Shin, Seung Won; Jung, Myunghwan; Lee, Su-Hyung; Kim, Dae-Yong; Yoo, Han Sang

    2015-01-01

    Paratuberculosis or Johne’s disease is a chronic granulomatous enteropathy in ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP) infection. In the present study, we examined the host response to MAP infection in spleens of mice in order to investigate the host immunopathology accompanying host-pathogen interaction. Transcriptional profiles of the MAP-infected mice at 3 and 6 weeks p.i. showed severe histopathological changes, whereas those at 12 weeks p.i. displayed reduced lesion severity in the spleen and liver. MAP-infected mice at 3 and 6 weeks p.i. showed up-regulation of interferon-related genes, scavenger receptor, and complement components, suggesting an initial innate immune reaction, such as macrophage activation, bactericidal activity, and macrophage invasion of MAP. Concurrently, MAP-infected mice at 3 and 6 weeks p.i. were also suggested to express M2 macrophage phenotype with up-regulation of Mrc1, and Marco and down-regulation of MHC class II, Ccr7, and Irf5, and canonical pathways related to the T cell response including ICOS-ICOSL signaling in T helper cells, calcium-induced T lymphocyte apoptosis, and CD28 signaling in T helper cell. These results provide information which furthers the understanding of the immunopathologic response to MAP infection in mice, thereby providing insights valuable for research into the pathogenesis for MAP infection. PMID:26439498

  17. Probiotics, prebiotics and immunomodulation of gut mucosal defences: homeostasis and immunopathology.

    PubMed

    Hardy, Holly; Harris, Jennifer; Lyon, Eleanor; Beal, Jane; Foey, Andrew D

    2013-06-01

    Probiotics are beneficial microbes that confer a realistic health benefit on the host, which in combination with prebiotics, (indigestible dietary fibre/carbohydrate), also confer a health benefit on the host via products resulting from anaerobic fermentation. There is a growing body of evidence documenting the immune-modulatory ability of probiotic bacteria, it is therefore reasonable to suggest that this is potentiated via a combination of prebiotics and probiotics as a symbiotic mix. The need for probiotic formulations has been appreciated for the health benefits in "topping up your good bacteria" or indeed in an attempt to normalise the dysbiotic microbiota associated with immunopathology. This review will focus on the immunomodulatory role of probiotics and prebiotics on the cells, molecules and immune responses in the gut mucosae, from epithelial barrier to priming of adaptive responses by antigen presenting cells: immune fate decision-tolerance or activation? Modulation of normal homeostatic mechanisms, coupled with findings from probiotic and prebiotic delivery in pathological studies, will highlight the role for these xenobiotics in dysbiosis associated with immunopathology in the context of inflammatory bowel disease, colorectal cancer and hypersensitivity. PMID:23760057

  18. Cutaneous Manifestations of Non-Celiac Gluten Sensitivity: Clinical Histological and Immunopathological Features

    PubMed Central

    Bonciolini, Veronica; Bianchi, Beatrice; Del Bianco, Elena; Verdelli, Alice; Caproni, Marzia

    2015-01-01

    Background: The dermatological manifestations associated with intestinal diseases are becoming more frequent, especially now when new clinical entities, such as Non-Celiac Gluten Sensitivity (NCGS), are identified. The existence of this new entity is still debated. However, many patients with diagnosed NCGS that present intestinal manifestations have skin lesions that need appropriate characterization. Methods: We involved 17 patients affected by NCGS with non-specific cutaneous manifestations who got much better after a gluten free diet. For a histopathological and immunopathological evaluation, two skin samples from each patient and their clinical data were collected. Results: The median age of the 17 enrolled patients affected by NCGS was 36 years and 76% of them were females. On the extensor surfaces of upper and lower limbs in particular, they all presented very itchy dermatological manifestations morphologically similar to eczema, psoriasis or dermatitis herpetiformis. This similarity was also confirmed histologically, but the immunopathological analysis showed the prevalence of deposits of C3 along the dermo-epidermal junction with a microgranular/granular pattern (82%). Conclusions: The exact characterization of new clinical entities such as Cutaneous Gluten Sensitivity and NCGS is an important objective both for diagnostic and therapeutic purposes, since these are patients who actually benefit from a GFD (Gluten Free Diet) and who do not adopt it only for fashion. PMID:26389946

  19. Probiotics, Prebiotics and Immunomodulation of Gut Mucosal Defences: Homeostasis and Immunopathology

    PubMed Central

    Hardy, Holly; Harris, Jennifer; Lyon, Eleanor; Beal, Jane; Foey, Andrew D.

    2013-01-01

    Probiotics are beneficial microbes that confer a realistic health benefit on the host, which in combination with prebiotics, (indigestible dietary fibre/carbohydrate), also confer a health benefit on the host via products resulting from anaerobic fermentation. There is a growing body of evidence documenting the immune-modulatory ability of probiotic bacteria, it is therefore reasonable to suggest that this is potentiated via a combination of prebiotics and probiotics as a symbiotic mix. The need for probiotic formulations has been appreciated for the health benefits in “topping up your good bacteria” or indeed in an attempt to normalise the dysbiotic microbiota associated with immunopathology. This review will focus on the immunomodulatory role of probiotics and prebiotics on the cells, molecules and immune responses in the gut mucosae, from epithelial barrier to priming of adaptive responses by antigen presenting cells: immune fate decision—tolerance or activation? Modulation of normal homeostatic mechanisms, coupled with findings from probiotic and prebiotic delivery in pathological studies, will highlight the role for these xenobiotics in dysbiosis associated with immunopathology in the context of inflammatory bowel disease, colorectal cancer and hypersensitivity. PMID:23760057

  20. Multiple mechanisms contribute to impairment of type 1 interferon production during chronic lymphocytic choriomeningitis virus infection of mice.

    PubMed

    Lee, Lian Ni; Burke, Shannon; Montoya, Maria; Borrow, Persephone

    2009-06-01

    Type 1 IFNs, innate cytokines with important effector and immunomodulatory properties, are rapidly induced in the acute phase of many virus infections; however, this is generally a transient response that is not sustained during virus persistence. To gain insight into mechanisms that can contribute to down-regulation of type 1 IFN production during virus persistence, we analyzed type 1 IFN production during acute and chronic lymphocytic choriomeningitis virus (LCMV) infection. High-level type 1 IFN production was transiently up-regulated in cells including plasmacytoid and conventional dendritic cells (DCs) following LCMV infection of mice, but LCMV persistence was associated with only low-level type 1 IFN production. Nonetheless, chronically infected mice were able to up-regulate type 1 IFN production in response to TLR3, 7, and 9 ligands, albeit less efficiently than uninfected mice. Splenic DC numbers in mice chronically infected with LCMV were decreased, and the remaining cells exhibited a reduced response to TLR stimulation. LCMV-infected cell lines efficiently up-regulated type 1 IFN production following TLR ligation and infection with a DNA virus, but exhibited a defect in type 1 IFN induction following infection with Sendai, an RNA virus. This block in type 1 IFN production by infected cells, together with abnormalities in DC numbers and functions, likely contribute to the low-level type 1 IFN production in mice chronically infected with LCMV. Impairment of type 1 IFN production may both promote virus persistence and impact on host immunocompetence. Understanding the mechanisms involved may assist in development of strategies for control of virus persistence and superinfection. PMID:19454715

  1. Uncovering subdominant cytotoxic T-lymphocyte responses in lymphocytic choriomeningitis virus-infected BALB/c mice.

    PubMed Central

    van der Most, R G; Concepcion, R J; Oseroff, C; Alexander, J; Southwood, S; Sidney, J; Chesnut, R W; Ahmed, R; Sette, A

    1997-01-01

    The cytotoxic T-lymphocyte response against lymphocytic choriomeningitis virus (LCMV) in BALB/c mice is predominantly directed against a single, Ld-restricted epitope in the viral nucleoprotein (residues 118 to 126). To investigate whether any Kd/Dd-restricted responses were activated but did not expand during the primary response, we used a BALB/c mutant, BALB/c-H-2dm2, which does not express the Ld molecule. Splenocytes from LCMV-infected BALB/c mice were transferred into irradiated BALB/c-H-2dm2 mice and rechallenged with LCMV. Thus, they were exposed to an antigenic stimulus without the involvement of the immunodominant Ld-restricted epitope. In this adoptive transfer model, the donor splenocytes protected the recipient mice against chronic LCMV infection by mounting a potent Kd- and/or Dd-restricted secondary antiviral response. Analysis of a panel of Kd binding LCMV peptides revealed that residues 283 to 291 from the viral glycoprotein (GP(283-291)) comprise a major new epitope in the adoptive transfer model. Because the donor splenocytes were first activated during the primary infection in BALB/c mice, the GP(283-291) epitope is a subdominant epitope in BALB/c mice that becomes dominant after rechallenge in BALB/c-H-2dm2 mice. This study makes two points. First, it shows that subdominant CTL responses can be protective, and second, it provides a general experimental approach for uncovering subdominant CTL responses in vivo. This strategy can be used to identify subdominant T-cell responses in other systems. PMID:9188577

  2. The role of arachidonic acid metabolism in virus-induced alveolar macrophage dysfunction

    SciTech Connect

    Laegreid, W.W.

    1988-01-01

    Alveolar macrophages (AM) recovered from virus-infected lungs have decreased phagocytic, respiratory burst and bactericidal activities. The studies described below investigated the role of eicosanoids in virus induced AM bactericidal dysfunction. The spectrum of eicosanoid metabolites which bovine AM are capable of producing was determined. Cultured AM were exposed to {sup 3}H-arachidonate for 1 hour, stimulated for 4 hours with A23187, phorbol myristate acetate or zymosan and the supernatants extracted and analyzed by HPLC. All stimuli tested caused the release of these cyclooxygenase metabolites: thromboxane B{sub 2}, PGF{sub 2}, PGE{sub 2}, PGD{sub 2} and HHT. The effect of this enhanced release of arachidonate metabolites on the ability of AM to kill bacteria was evaluated. Preincubation with cyclooxygenase inhibitors or dual cyclooxygenase and lipoxygenase inhibitors resulted in partial reversal of the virus-induced bactericidal deficit in PI3 infected AM.

  3. Virus-induced gene silencing in the rapid cycling columbine Aquilegia coerulea "Origami".

    PubMed

    Sharma, Bharti; Kramer, Elena M

    2013-01-01

    Aquilegia Origami is an emerging model system for ecology and evolution, which has numerous genetic and genomic tools. Virus-induced gene silencing (VIGS) has been established as an effective approach to study gene function in Aquilegia. In the current protocol, we demonstrate VIGS using Agrobacterium strain GV3101 carrying tobacco rattle virus (TRV)-based constructs to infect Aquilegia coerulea "Origami" plants via vacuum infiltration. PMID:23386296

  4. Comparative analysis of radiation- and virus-induced leukemias in BALB/c mice

    SciTech Connect

    Newcomb, E.W.; Binari, R.; Fleissner, E.

    1985-01-15

    Endogenous murine leukemia virus (MuLV) proviral copies were analyzed in thymomas induced in normal BALB/c (Fv-1b) and in Fv-1n congenic mice by X-irradiation. Both strains of mice developed leukemia with similar kinetics, indicating that N-tropism of endogenous MuLV was not a rate-limiting factor in development of disease. Southern blot analysis, using a probe specific for ecotropic virus and for ecotropic-specific sequences retained in pathogenic, env-recombinant viruses, showed that the majority of radiation leukemias lacked newly acquired, clonally integrated, proviruses. This was in contrast to virus-induced leukemias, which routinely exhibited several new proviral integration sites. When an internal proviral DNA restriction fragment was monitored, some radiation leukemias showed evidence of nonclonal infection, accounting for more frequent isolation of infectious virus from such leukemias. Differences in expression of T-cell surface antigens were found in X-ray-induced and virus-induced leukemias. All radiation leukemias were TL positive, whereas virus-induced leukemias were primarily negative for TL. Some differences were also found in Lyt-1 and Lyt-2 expression. The data as a whole suggest that, in the majority of cases, radiation leukemogenesis is not initiated by a viral route--that is, the sort of viral mechanism for which exogenous infection by known pathogenic MuLV is the paradigm.

  5. Influenza Virus Induces Inflammatory Response in Mouse Primary Cortical Neurons with Limited Viral Replication.

    PubMed

    Wang, Gefei; Li, Rui; Jiang, Zhiwu; Gu, Liming; Chen, Yanxia; Dai, Jianping; Li, Kangsheng

    2016-01-01

    Unlike stereotypical neurotropic viruses, influenza A viruses have been detected in the brain tissues of human and animal models. To investigate the interaction between neurons and influenza A viruses, mouse cortical neurons were isolated, infected with human H1N1 influenza virus, and then examined for the production of various inflammatory molecules involved in immune response. We found that replication of the influenza virus in neurons was limited, although early viral transcription was not affected. Virus-induced neuron viability decreased at 6 h postinfection (p.i.) but increased at 24 h p.i. depending upon the viral strain. Virus-induced apoptosis and cytopathy in primary cortical neurons were not apparent at 24 h p.i. The mRNA levels of inflammatory cytokines, chemokines, and type I interferons were upregulated at 6 h and 24 h p.i. These results indicate that the influenza virus induces inflammatory response in mouse primary cortical neurons with limited viral replication. The cytokines released in viral infection-induced neuroinflammation might play critical roles in influenza encephalopathy, rather than in viral replication-induced cytopathy. PMID:27525278

  6. Influenza Virus Induces Inflammatory Response in Mouse Primary Cortical Neurons with Limited Viral Replication

    PubMed Central

    Jiang, Zhiwu; Gu, Liming; Chen, Yanxia

    2016-01-01

    Unlike stereotypical neurotropic viruses, influenza A viruses have been detected in the brain tissues of human and animal models. To investigate the interaction between neurons and influenza A viruses, mouse cortical neurons were isolated, infected with human H1N1 influenza virus, and then examined for the production of various inflammatory molecules involved in immune response. We found that replication of the influenza virus in neurons was limited, although early viral transcription was not affected. Virus-induced neuron viability decreased at 6 h postinfection (p.i.) but increased at 24 h p.i. depending upon the viral strain. Virus-induced apoptosis and cytopathy in primary cortical neurons were not apparent at 24 h p.i. The mRNA levels of inflammatory cytokines, chemokines, and type I interferons were upregulated at 6 h and 24 h p.i. These results indicate that the influenza virus induces inflammatory response in mouse primary cortical neurons with limited viral replication. The cytokines released in viral infection-induced neuroinflammation might play critical roles in influenza encephalopathy, rather than in viral replication-induced cytopathy. PMID:27525278

  7. Absence of missense mutations in activated c-myc genes in avian leukosis virus-induced B-cell lymphomas

    SciTech Connect

    Hahn, M.; Hayward, W.S.

    1988-06-01

    The authors determined the nucleotide sequences of two independent DNA clones which contained the activated c-myc genes from avian leukosis virus-induced B-cell lymphomas. Neither of these c-myce genes contained missense mutations. This strongly supports the notion that the c-myc photo-oncogene in avian leukosis virus-induced B-cell lymphomas can be oncogenically activated by altered expression of the gene without a change in the primary structure of the gene product.

  8. Reduced Tyk2 gene expression in β-cells due to natural mutation determines susceptibility to virus-induced diabetes.

    PubMed

    Izumi, Kenichi; Mine, Keiichiro; Inoue, Yoshitaka; Teshima, Miho; Ogawa, Shuichiro; Kai, Yuji; Kurafuji, Toshinobu; Hirakawa, Kanako; Miyakawa, Daiki; Ikeda, Haruka; Inada, Akari; Hara, Manami; Yamada, Hisakata; Akashi, Koichi; Niho, Yoshiyuki; Ina, Keisuke; Kobayashi, Takashi; Yoshikai, Yasunobu; Anzai, Keizo; Yamashita, Teruo; Minagawa, Hiroko; Fujimoto, Shuji; Kurisaki, Hironori; Shimoda, Kazuya; Katsuta, Hitoshi; Nagafuchi, Seiho

    2015-01-01

    Accumulating evidence suggests that viruses play an important role in the development of diabetes. Although the diabetogenic encephalomyocarditis strain D virus induces diabetes in restricted lines of inbred mice, the susceptibility genes to virus-induced diabetes have not been identified. We report here that novel Tyrosine kinase 2 (Tyk2) gene mutations are present in virus-induced diabetes-sensitive SJL and SWR mice. Mice carrying the mutant Tyk2 gene on the virus-resistant C57BL/6 background are highly sensitive to virus-induced diabetes. Tyk2 gene expression is strongly reduced in Tyk2-mutant mice, associated with low Tyk2 promoter activity, and leads to decreased expression of interferon-inducible genes, resulting in significantly compromised antiviral response. Tyk2-mutant pancreatic β-cells are unresponsive even to high dose of Type I interferon. Reversal of virus-induced diabetes could be achieved by β-cell-specific Tyk2 gene expression. Thus, reduced Tyk2 gene expression in pancreatic β-cells due to natural mutation is responsible for susceptibility to virus-induced diabetes. PMID:25849081

  9. Reduced Tyk2 gene expression in β-cells due to natural mutation determines susceptibility to virus-induced diabetes

    PubMed Central

    Izumi, Kenichi; Mine, Keiichiro; Inoue, Yoshitaka; Teshima, Miho; Ogawa, Shuichiro; Kai, Yuji; Kurafuji, Toshinobu; Hirakawa, Kanako; Miyakawa, Daiki; Ikeda, Haruka; Inada, Akari; Hara, Manami; Yamada, Hisakata; Akashi, Koichi; Niho, Yoshiyuki; Ina, Keisuke; Kobayashi, Takashi; Yoshikai, Yasunobu; Anzai, Keizo; Yamashita, Teruo; Minagawa, Hiroko; Fujimoto, Shuji; Kurisaki, Hironori; Shimoda, Kazuya; Katsuta, Hitoshi; Nagafuchi, Seiho

    2015-01-01

    Accumulating evidence suggests that viruses play an important role in the development of diabetes. Although the diabetogenic encephalomyocarditis strain D virus induces diabetes in restricted lines of inbred mice, the susceptibility genes to virus-induced diabetes have not been identified. We report here that novel Tyrosine kinase 2 (Tyk2) gene mutations are present in virus-induced diabetes-sensitive SJL and SWR mice. Mice carrying the mutant Tyk2 gene on the virus-resistant C57BL/6 background are highly sensitive to virus-induced diabetes. Tyk2 gene expression is strongly reduced in Tyk2-mutant mice, associated with low Tyk2 promoter activity, and leads to decreased expression of interferon-inducible genes, resulting in significantly compromised antiviral response. Tyk2-mutant pancreatic β-cells are unresponsive even to high dose of Type I interferon. Reversal of virus-induced diabetes could be achieved by β-cell-specific Tyk2 gene expression. Thus, reduced Tyk2 gene expression in pancreatic β-cells due to natural mutation is responsible for susceptibility to virus-induced diabetes. PMID:25849081

  10. Immunopathologic differences of Sjögren's syndrome versus sicca syndrome in HCV and HIV infection

    PubMed Central

    2011-01-01

    A clinical picture of dry eye and dry mouth with the histological counterpart of focal lymphocytic sialoadenitis, usually detected in minor salivary glands, is considered the hallmark of Sjögren's syndrome. The association of sicca complaints and focal sialoadenitis can be also found in a number of other diseases, including some systemic viral infections. Among these conditions, chronic hepatitis C virus infection, associated with mixed cryoglobulinaemia and extra-hepatic manifestations, and HIV infection, particularly in the phase of diffuse interstitial lymphocytic infiltration, may mimic the clinical and histological aspects of Sjögren's syndrome. However, each disorder is characterised by specific, disease-related immunopathological aspects. Besides sicca complaints, the various disorders may also share a number of systemic extra-glandular features and the possible development of mucosa-associated lymphoid tissue lymphomas. This latter event represents in all of these diseases the final result of an antigen-driven chronic stimulation of B lymphocytes. PMID:21888688

  11. Subgingival Microbial Communities in Leukocyte Adhesion Deficiency and Their Relationship with Local Immunopathology

    PubMed Central

    Moutsopoulos, Niki M.; Abusleme, Loreto; Greenwell-Wild, Teresa; Dutzan, Nicolas; Paster, Bruce J.; Munson, Peter J.; Fine, Daniel H.; Uzel, Gulbu; Holland, Steven M.

    2015-01-01

    Leukocyte Adhesion Deficiency I (LAD-I) is a primary immunodeficiency caused by single gene mutations in the CD18 subunit of β2 integrins which result in defective transmigration of neutrophils into the tissues. Affected patients suffer from recurrent life threatening infections and severe oral disease (periodontitis). Microbial communities in the local environment (subgingival plaque) are thought to be the triggers for inflammatory periodontitis, yet little is known regarding the microbial communities associated with LAD-I periodontitis. Here we present the first comprehensive characterization of the subgingival communities in LAD-I, using a 16S rRNA gene-based microarray, and investigate the relationship of this tooth adherent microbiome to the local immunopathology of periodontitis. We show that the LAD subgingival microbiome is distinct from that of health and Localized Aggressive Periodontitits. Select periodontitis-associated species in the LAD microbiome included Parvimonas micra, Porphyromonas endodontalis, Eubacterium brachy and Treponema species. Pseudomonas aeruginosa, a bacterium not typically found in subgingival plaque is detected in LAD-I. We suggest that microbial products from LAD-associated communities may have a role in stimulating the local inflammatory response. We demonstrate that bacterial LPS translocates into the lesions of LAD-periodontitis potentially triggering immunopathology. We also show in in vitro assays with human macrophages and in vivo in animal models that microbial products from LAD-associated subgingival plaque trigger IL-23-related immune responses, which have been shown to dominate in patient lesions. In conclusion, our current study characterizes the subgingival microbial communities in LAD-periodontitis and supports their role as triggers of disease pathogenesis. PMID:25741691

  12. Virus-triggered acquired immunodeficiency by cytotoxic T-cell-dependent destruction of antigen-presenting cells and lymph follicle structure.

    PubMed Central

    Odermatt, B; Eppler, M; Leist, T P; Hengartner, H; Zinkernagel, R M

    1991-01-01

    Virus-induced acquired immune suppression in mice infected with lymphocytic choriomeningitis virus is shown here to be caused by the CD8+-T-cell-dependent elimination of macrophages/antigen-presenting cells. Surprisingly, this is associated with severe destruction of the follicular organization of lymphoid organs, indicating a crucial role for dendritic cells and marginal zone macrophages in maintaining follicular structure. Once established, this immunopathology cannot be readily reversed by the elimination of CD8+ effector cells. Such a T-cell-mediated pathogenesis may play a pivotal role in acquired virus-induced immunosuppression and may represent one strategy by which virus escapes immune surveillance and establishes persistent infections in initially immunocompetent hosts. Images PMID:1910175

  13. Lessons from T cell responses to virus induced tumours for cancer eradication in general.

    PubMed

    Melief, C J; Kast, W M

    1992-01-01

    Immunotherapy of virus induced tumours by adoptive transfer of virus specific cytotoxic T cells (CTL) is now feasible in experimental murine systems. These CTL recognize viral peptide sequences of defined length presented in the groove of MHC class I molecules. Effective eradication of large tumour masses requires coadministration of IL-2. In essence, T cell immunity against virus induced tumours does not differ from anti-viral T cell immunity in general. Tumour escape strategies are numerous but, in various instances, can be counteracted by defined measures. Initiation of CTL responses against poorly immunogenic non-virus induced tumours (the majority of human cancer) requires novel strategies to overcome T cell inertia. Rather than waiting to see whether tumour specific CTL (against unknown antigens) can be cultured from TIL, we propose an alternative strategy in which CTL are raised against target molecules of choice, including differentiation antigens of restricted tissue distribution (autoantigens) or mutated/overexpressed oncogene products. The various steps proposed include: (a) identification of target molecules of choice; (b) identification in these target molecules of MHC allele specific peptide motifs involved in peptide binding to MHC molecules; (c) evaluation of actual binding of such peptides to specific MHC class I molecules; (d) in vitro CTL response induction by such peptides, presented either by highly efficient antigen presenting cells (such as processing defective cells, which carry empty MHC class I molecules) loaded with a single peptide or by dendritic cells, both cell types being capable of primary CTL response induction in vitro and (e) adoptive transfer of tumour specific CTL generated in vivo or, more conveniently, vaccination with immunodominant peptides. The latter possibility seems to be feasible because peptide vaccination with a single immunodominant viral peptide can install CTL memory and confer protection against lethal virus

  14. MR VIGS: microRNA-based virus-induced gene silencing in plants.

    PubMed

    Chen, Weiwei; Zhang, Qi; Kong, Junhua; Hu, Feng; Li, Bin; Wu, Chaoqun; Qin, Cheng; Zhang, Pengcheng; Shi, Nongnong; Hong, Yiguo

    2015-01-01

    In plants, microRNA (miRNA)-based virus-induced gene silencing, dubbed MR VIGS, is a powerful technique to delineate the biological functions of genes. By targeting to a specific sequence, miRNAs can knock down expression of genes with fewer off-target effects. Here, using a modified Cabbage leaf curling virus (CaLCuV) and Tobacco rattle virus (TRV) as vectors, we describe two virus-based miRNA expression systems to perform MR VIGS for plant functional genomics assays. PMID:25740363

  15. RIG-I Signaling Is Essential for Influenza B Virus-Induced Rapid Interferon Gene Expression

    PubMed Central

    Österlund, Pamela; Westenius, Veera; Latvala, Sinikka; Diamond, Michael S.; Gale, Michael; Julkunen, Ilkka

    2015-01-01

    ABSTRACT Influenza B virus causes annual epidemics and, along with influenza A virus, accounts for substantial disease and economic burden throughout the world. Influenza B virus infects only humans and some marine mammals and is not responsible for pandemics, possibly due to a very low frequency of reassortment and a lower evolutionary rate than that of influenza A virus. Influenza B virus has been less studied than influenza A virus, and thus, a comparison of influenza A and B virus infection mechanisms may provide new insight into virus-host interactions. Here we analyzed the early events in influenza B virus infection and interferon (IFN) gene expression in human monocyte-derived macrophages and dendritic cells. We show that influenza B virus induces IFN regulatory factor 3 (IRF3) activation and IFN-λ1 gene expression with faster kinetics than does influenza A virus, without a requirement for viral protein synthesis or replication. Influenza B virus-induced activation of IRF3 required the fusion of viral and endosomal membranes, and nuclear accumulation of IRF3 and viral NP occurred concurrently. In comparison, immediate early IRF3 activation was not observed in influenza A virus-infected macrophages. Experiments with RIG-I-, MDA5-, and RIG-I/MDA5-deficient mouse fibroblasts showed that RIG-I is the critical pattern recognition receptor needed for the influenza B virus-induced activation of IRF3. Our results show that innate immune mechanisms are activated immediately after influenza B virus entry through the endocytic pathway, whereas influenza A virus avoids early IRF3 activation and IFN gene induction. IMPORTANCE Recently, a great deal of interest has been paid to identifying the ligands for RIG-I under conditions of natural infection, as many previous studies have been based on transfection of cells with different types of viral or synthetic RNA structures. We shed light on this question by analyzing the earliest step in innate immune recognition of

  16. End products of glutamine oxidation in MC-29 virus-induced chicken hepatoma mitochondria.

    PubMed

    Matsuno, T

    1989-10-01

    Products of glutamine metabolism were examined in the MC-29 virus-induced chicken hepatoma mitochondria incubated in vitro. Glutamine oxidation proceeded in the tumor mitochondria exclusively via a pathway involving glutamic-oxalacetic transaminase. Malate stimulated aspartate production from glutamine, while pyruvate exerted suppressive effect on aspartate production with little alanine formation. The mitochondria of this hepatoma are unique in that the metabolic pattern and response to malate and pyruvate are essentially inconsistent with those reported in normal cells as well as those proposed by Moreadith and Lehninger in various tumor cells. PMID:2571353

  17. Comorbidity of Narcolepsy Type 1 With Autoimmune Diseases and Other Immunopathological Disorders: A Case-Control Study

    PubMed Central

    Martinez-Orozco, Francisco Javier; Vicario, Jose Luis; De Andres, Clara; Fernandez-Arquero, Miguel; Peraita-Adrados, Rosa

    2016-01-01

    Background Several evidences suggest that autoimmune diseases (ADs) tend to co-occur in an individual and within the same family. Narcolepsy type 1 (NT1) is a chronic sleep disorder caused by a selective loss of hypocretin-producing neurons due to a mechanism of neural destruction that indicates an autoimmune pathogenesis, although no evidence is available. We report on the comorbidity of ADs and other immunopathological diseases (including allergy diseases) in narcolepsy. Methods We studied 158 Caucasian NT1 patients (60.7% male; mean age 49.4 ± 19.7 years), in whom the diagnosis was confirmed by polysomnography followed by a multiple sleep latency test, or by hypocretin-1 levels measurements. Results Thirty out of 158 patients (18.99%; 53.3% female; 29 sporadic and one familial cases) had one or more immunopathological diseases associated. A control group of 151 subjects were matched by gender and age with the narcolepsy patients. Results demonstrated that there was a higher frequency of ADs in our series of narcolepsy patients compared to the sample of general population (odds ratio: 3.17; 95% confidence interval: 1.01 - 10.07; P = 0.040). A temporal relationship with the age at onset of the diseases was found. Conclusions Cataplexy was significantly more severe in NT1 patients with immunopathological diseases, and immunopathological diseases are a risk factor for severe forms of cataplexy in our series (odds ratio: 23.6; 95% confidence interval: 5.5 - 100.1). PMID:27298657

  18. Age-related Defects in Ocular and Nasal Mucosal Immune System and the Immunopathology of Dry Eye Disease.

    PubMed

    Farid, Marjan; Agrawal, Anshu; Fremgen, Daniel; Tao, Jeremiah; Chuyi, He; Nesburn, Anthony B; BenMohamed, Lbachir

    2016-06-01

    Dry eye disease (DED) is a prevalent public health concern that affects up to 30% of adults and is particularly chronic and severe in the elderly. Two interconnected mechanisms cause DED: (1) an age-related dysfunction of lacrimal and meibomian glands, which leads to decreased tear production and/or an increase in tear evaporation; and (2) an age-related uncontrolled inflammation of the surface of the eye triggered by yet-to-be-determined internal immunopathological mechanisms, independent of tear deficiency and evaporation. In this review we summarize current knowledge on animal models that mimic both the severity and chronicity of inflammatory DED and that have been reliably used to provide insights into the immunopathological mechanisms of DED, and we provide an overview of the opportunities and limitations of the rabbit model in investigating the role of both ocular and nasal mucosal immune systems in the immunopathology of inflammatory DED and in testing novel immunotherapies aimed at delaying or reversing the uncontrolled age-related inflammatory DED. PMID:25535823

  19. Age-related Defects in Ocular and Nasal Mucosal Immune System and the Immunopathology of Dry Eye Disease

    PubMed Central

    Farid, Marjan; Agrawal, Anshu; Fremgen, Daniel; Tao, Jeremiah; Chuyi, He; Nesburn, Anthony B.; BenMohamed, Lbachir

    2014-01-01

    Dry eye disease (DED) is a prevalent public health concern that affects up to 30% of adults and is particularly chronic and severe in the elderly. Two interconnected mechanisms cause DED: (1) an age-related dysfunction of lacrimal and meibomian glands, which leads to decreased tear production and/or an increase in tear evaporation; and (2) an age-related uncontrolled inflammation of the surface of the eye triggered by yet-to-be-determined internal immunopathological mechanisms, independent of tear deficiency and evaporation. In this review we summarize current knowledge on animal models that mimic both the severity and chronicity of inflammatory DED and that have been reliably used to provide insights into the immunopathological mechanisms of DED, and we provide an overview of the opportunities and limitations of the rabbit model in investigating the role of both ocular and nasal mucosal immune systems in the immunopathology of inflammatory DED and in testing novel immunotherapies aimed at delaying or reversing the uncontrolled age-related inflammatory DED. PMID:25535823

  20. Immunization with non-replicating E. coli minicells delivering both protein antigen and DNA protects mice from lethal challenge with lymphocytic choriomeningitis virus

    PubMed Central

    Giacalone, Matthew J.; Zapata, Juan C.; Berkley, Neil L.; Sabbadini, Roger A.; Chu, Yen-Lin; Salvato, Maria S.; McGuire, Kathleen L.

    2008-01-01

    In the midst of new investigations into the mechanisms of both delivery and protection of new vaccines and vaccine carriers, it has become clear that immunization with delivery mechanisms that do not involve living, replicating organisms are vastly preferred. In this report, non-replicating bacterial minicells simultaneously co-delivering the nucleoprotein (NP) of lymphocytic choriomeningitis virus (LCMV) and the corresponding DNA vaccine were tested for the ability to generate protective cellular immune responses in mice. It was found that good protection (89%) was achieved after intramuscular administration, moderate protection (31%) was achieved after intranasal administration, and less protection (7%) was achieved following gastric immunization. These results provide a solid foundation on which to pursue the use of bacterial minicells as a non-replicating vaccine delivery platform. PMID:17258845

  1. Establishment of a highly efficient virus-inducible CRISPR/Cas9 system in insect cells.

    PubMed

    Dong, Zhan-Qi; Chen, Ting-Ting; Zhang, Jun; Hu, Nan; Cao, Ming-Ya; Dong, Fei-Fan; Jiang, Ya-Ming; Chen, Peng; Lu, Cheng; Pan, Min-Hui

    2016-06-01

    Although current antiviral strategies can inhibit baculovirus infection and decrease viral DNA replication to a certain extent, novel tools are required for specific and accurate elimination of baculovirus genomes from infected insects. Using the newly developed clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease (CRISPR/Cas9) technology, we disrupted a viral genome in infected insect cells in vitro as a defense against viral infection. We optimized the CRISPR/Cas9 system to edit foreign and viral genome in insect cells. Using Bombyx mori nucleopolyhedrovirus (BmNPV) as a model, we found that the CRISPR/Cas9 system was capable of cleaving the replication key factor ie-1 in BmNPV thus effectively inhibiting virus proliferation. Furthermore, we constructed a virus-inducible CRISPR/Cas9 editing system, which minimized the probability of off-target effects and was rapidly activated after viral infection. This is the first report describing the application of the CRISPR/Cas9 system in insect antiviral research. Establishment of a highly efficient virus-inducible CRISPR/Cas9 system in insect cells provides insights to produce virus-resistant transgenic strains for future. PMID:26979473

  2. Virus-induced gene complementation reveals a transcription factor network in modulation of tomato fruit ripening

    PubMed Central

    Zhou, Tao; Zhang, Hang; Lai, Tongfei; Qin, Cheng; Shi, Nongnong; Wang, Huizhong; Jin, Mingfei; Zhong, Silin; Fan, Zaifeng; Liu, Yule; Wu, Zirong; Jackson, Stephen; Giovannoni, James J.; Rolin, Dominique; Gallusci, Philippe; Hong, Yiguo

    2012-01-01

    Plant virus technology, in particular virus-induced gene silencing, is a widely used reverse- and forward-genetics tool in plant functional genomics. However the potential of virus technology to express genes to induce phenotypes or to complement mutants in order to understand the function of plant genes is not well documented. Here we exploit Potato virus X as a tool for virus-induced gene complementation (VIGC). Using VIGC in tomato, we demonstrated that ectopic viral expression of LeMADS-RIN, which encodes a MADS-box transcription factor (TF), resulted in functional complementation of the non-ripening rin mutant phenotype and caused fruits to ripen. Comparative gene expression analysis indicated that LeMADS-RIN up-regulated expression of the SBP-box (SQUAMOSA promoter binding protein-like) gene LeSPL-CNR, but down-regulated the expression of LeHB-1, an HD-Zip homeobox TF gene. Our data support the hypothesis that a transcriptional network may exist among key TFs in the modulation of fruit ripening in tomato. PMID:23150786

  3. Type I IFN signaling triggers immunopathology in tuberculosis-susceptible mice by modulating lung phagocyte dynamics

    PubMed Central

    Dorhoi, Anca; Yeremeev, Vladimir; Nouailles, Geraldine; Weiner, January; Jörg, Sabine; Heinemann, Ellen; Oberbeck-Müller, Dagmar; Knaul, Julia K; Vogelzang, Alexis; Reece, Stephen T; Hahnke, Karin; Mollenkopf, Hans-Joachim; Brinkmann, Volker; Kaufmann, Stefan H E

    2014-01-01

    General interest in the biological functions of IFN type I in Mycobacterium tuberculosis (Mtb) infection increased after the recent identification of a distinct IFN gene expression signature in tuberculosis (TB) patients. Here, we demonstrate that TB-susceptible mice lacking the receptor for IFN I (IFNAR1) were protected from death upon aerogenic infection with Mtb. Using this experimental model to mimic primary progressive pulmonary TB, we dissected the immune processes affected by IFN I. IFNAR1 signaling did not affect T-cell responses, but markedly altered migration of inflammatory monocytes and neutrophils to the lung. This process was orchestrated by IFNAR1 expressed on both immune and tissue-resident radioresistant cells. IFNAR1-driven TB susceptibility was initiated by augmented Mtb replication and in situ death events, along with CXCL5/CXCL1-driven accumulation of neutrophils in alveoli, followed by the discrete compartmentalization of Mtb in lung phagocytes. Early depletion of neutrophils rescued TB-susceptible mice to levels observed in mice lacking IFNAR1. We conclude that IFN I alters early innate events at the site of Mtb invasion leading to fatal immunopathology. These data furnish a mechanistic explanation for the detrimental role of IFN I in pulmonary TB and form a basis for understanding the complex roles of IFN I in chronic inflammation. PMID:24782112

  4. Immunopathology of experimental Chagas' disease: binding of T cells to Trypanosoma cruzi-infected heart tissue.

    PubMed Central

    Mortatti, R C; Maia, L C; de Oliveira, A V; Munk, M E

    1990-01-01

    The immunopathology of Chagas' disease was studied in the experimental model of chronic infection in C57BL/10JT or mice. Sublethal infection with Trypanosoma cruzi, Y strain, induced specific antibodies and a delayed hypersensitivity response to parasite antigens. Mice developed chronic chagasic myocarditis but not skeletal muscle myositis. Binding of T cells to infected heart tissue was investigated during short-term cocultivation of lymphocytes with heart cryostat sections. T cells from infected mice and from normal controls bound equally to myocardium and liver sections from both infected and normal mice. A search in depth was attempted with cells heavily tagged with 99mTc. Labeled T cells from chagasic mice bound to both normal and infected myocardium slices. 99mTc-labeled T cells from controls gave the same binding values. Glass-adherent spleen cells behaved identically to T cells. Prior treatment of the tissue with serum from chronically infected mice did not increase the number of binding cells. Peritoneal macrophages tagged with 99mTc-sulfur colloid also bound to infected myocardium slices. The binding of macrophages was not changed by pretreatment of infected tissue with anti-T, cruzi antibodies. In short, this work did not detect any population of T cells or macrophages which could bind specifically to infected heart tissue to initiate an autoreactive process. Images PMID:2228230

  5. Acquired cystic disease-associated renal cell carcinoma: further characterization of the morphologic and immunopathologic features.

    PubMed

    Ahn, Soomin; Kwon, Ghee Young; Cho, Yong Mee; Jun, Sun-Young; Choi, Chan; Kim, Hyun-Jung; Park, Yong Wook; Park, Weon Seo; Shim, Jung Won

    2013-12-01

    Acquired cystic disease-associated renal cell carcinoma (ACD-RCC) is a subtype of renal cell carcinoma (RCC) with unique morphologic features found exclusively in the background of end-stage renal disease. We analyzed the clinicopathologic features and immumoreactive profiles of 12 cases of ACD-RCC to further characterize this recently recognized entity. Review of histologic slides was performed in conjunction with immunohistochemical staining directed to the contemporary diagnostic antibodies and the putative target therapy-related markers. Histologically, the tumors showed characteristic inter-or intracellular microlumens and eosinophilic tumor cells. Intratumoral hemosiderin deposition and degenerating foamy tumor cells were consistent findings which were not previously described. Immunohistochemically, all the tumors were positive for alpha-methylacyl-CoA-racemase, CD10, pan-cytokeratin, PTEN (phosphatase and tensin homolog deleted on chromosome 10) and c-met, while negative for carbonic anhydrase-9, CD57, CD68, c-kit, pax-2, platelet-derived growth factor receptor (PDGFR)-α or vascular endothelial growth factor receptor (VEGFR)-2. Heterogenous staining was found for CK7 and kidney-specific cadherin. Positive reaction to c-met suggests its utility as a plausible therapeutic target in ACD-RCC. Thus, we present the unique morphologic and immunopathologic features of ACD-RCC, which may be helpful in both diagnostic and therapeutic aspects. PMID:23471757

  6. Immunity, immunopathology, and human vaccine development against sexually transmitted Chlamydia trachomatis

    PubMed Central

    Rey-Ladino, Jose; Ross, Allen GP; Cripps, Allan W

    2014-01-01

    This review examines the immunity, immunopathology, and contemporary problems of vaccine development against sexually transmitted Chlamydia trachomatis. Despite improved surveillance and treatment initiatives, the incidence of C. trachomatis infection has increased dramatically over the past 30 years in both the developed and developing world. Studies in animal models have shown that protective immunity to C. trachomatis is largely mediated by Th1 T cells producing IFN-γ which is needed to prevent dissemination of infection. Similar protection appears to develop in humans but in contrast to mice, immunity in humans may take years to develop. Animal studies and evidence from human infection indicate that immunity to C. trachomatis is accompanied by significant pathology in the upper genital tract. Although no credible evidence is currently available to indicate that autoimmunity plays a role, nevertheless, this underscores the necessity to design vaccines strictly based on chlamydial-specific antigens and to avoid those displaying even minimal sequence homologies with host molecules. Current advances in C. trachomatis vaccine development as well as alternatives for designing new vaccines for this disease are discussed. A novel approach for chlamydia vaccine development, based on targeting endogenous dendritic cells, is described. PMID:25483666

  7. Evaluating the ability of the barley stripe mosaic virus-induced gene silencing system to simultaneously silence two wheat genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-induced gene silencing (VIGS) is an important tool for rapid assessment of gene function in plants. The ability of the Barley Stripe Mosaic Virus (BSMV) VIGS system to simultaneously silence two genes was assessed by comparing the extent of down-regulation of the wheat PDS and SGT1 genes afte...

  8. Evaluating the Ability of the Barley Stripe Mosaic Virus-Induced Gene Silencing System to Simultaneously Silence Two Wheat Genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-induced gene silencing (VIGS) is an important tool for rapid assessment of gene function in plants. The ability of the Barley stripe mosaic virus (BSMV) VIGS system to simultaneously silence two genes was assessed by comparing the extent of down-regulation of the wheat PDS and SGT1 genes afte...

  9. Virus-induced gene silencing of RPC5-like subunit of RNA polymerase III caused pleiotropic effects in Nicotiana benthamiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In eukaryotic cells, RNA polymerase III is highly conserved, contains 17 subunits and transcribes housekeeping genes such as ribosomal 50S rRNA, tRNA and other small RNAs. Functional roles of the RPC5 are poorly characterized in the literature. In this work, we report that virus-induced gene silenci...

  10. Virus-induced gene silencing and transient gene expression in soybean using Bean pod mottle virus infectious clones

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-induced gene silencing (VIGS) is a powerful and rapid approach for determining the functions of plant genes. The basis of VIGS is that a viral genome is engineered so that it can carry fragments of plant genes, typically in the 200-300 base pair size range. The recombinant viruses are used to ...

  11. Persistent virus-induced gene silencing in asymptomatic accessions of Arabidopsis.

    PubMed

    Flores, Miguel A; Reyes, Maria I; Robertson, Dominique Niki; Kjemtrup, Susanne

    2015-01-01

    Coupled with the advantages afforded by the model plant Arabidopsis, virus-induced gene silencing (VIGS) offers a rapid means to assess gene function. The geminivirus vector based on Cabbage leaf curl virus described here has the benefits of small insert size and persistent silencing of the target gene through the life cycle of the plant. Here, we show that genetic variation in the vast collection of Arabidopsis accessions can be leveraged to ameliorate viral symptomology that accompanies the VIGS procedure. The plasticity of phenotypes under different day lengths or temperature conditions can be exploited to achieve maximum silencing efficacy in either vegetative or inflorescence tissue, according to the question being asked. Protocols and vectors for Agro-infiltration of primary leaves, subapical pricking in older plants, and microprojectile bombardment are described. PMID:25757779

  12. Sex-specific quantitative trait loci govern susceptibility to Theiler's murine encephalomyelitis virus-induced demyelination.

    PubMed Central

    Butterfield, Russell J; Roper, Randall J; Rhein, Dominic M; Melvold, Roger W; Haynes, Lia; Ma, Runlin Z; Doerge, R W; Teuscher, Cory

    2003-01-01

    Susceptibility to Theiler's murine encephalomyelitis virus-induced demyelination (TMEVD), a mouse model for multiple sclerosis (MS), is genetically controlled. Through a mouse-human comparative mapping approach, identification of candidate susceptibility loci for MS based on the location of TMEVD susceptibility loci may be possible. Composite interval mapping (CIM) identified quantitative trait loci (QTL) controlling TMEVD severity in male and female backcross populations derived from susceptible DBA/2J and resistant BALBc/ByJ mice. We report QTL on chromosomes 1, 5, 15, and 16 affecting male mice. In addition, we identified two QTL in female mice located on chromosome 1. Our results support the existence of three linked sex-specific QTL on chromosome 1 with opposing effects on the severity of the clinical signs of TMEV-induced disease in male and female mice. PMID:12663542

  13. Pleiotropic Effects of Levofloxacin, Fluoroquinolone Antibiotics, against Influenza Virus-Induced Lung Injury.

    PubMed

    Enoki, Yuki; Ishima, Yu; Tanaka, Ryota; Sato, Keizo; Kimachi, Kazuhiko; Shirai, Tatsuya; Watanabe, Hiroshi; Chuang, Victor T G; Fujiwara, Yukio; Takeya, Motohiro; Otagiri, Masaki; Maruyama, Toru

    2015-01-01

    Reactive oxygen species (ROS) and nitric oxide (NO) are major pathogenic molecules produced during viral lung infections, including influenza. While fluoroquinolones are widely used as antimicrobial agents for treating a variety of bacterial infections, including secondary infections associated with the influenza virus, it has been reported that they also function as anti-oxidants against ROS and as a NO regulator. Therefore, we hypothesized that levofloxacin (LVFX), one of the most frequently used fluoroquinolone derivatives, may attenuate pulmonary injuries associated with influenza virus infections by inhibiting the production of ROS species such as hydroxyl radicals and neutrophil-derived NO that is produced during an influenza viral infection. The therapeutic impact of LVFX was examined in a PR8 (H1N1) influenza virus-induced lung injury mouse model. ESR spin-trapping experiments indicated that LVFX showed scavenging activity against neutrophil-derived hydroxyl radicals. LVFX markedly improved the survival rate of mice that were infected with the influenza virus in a dose-dependent manner. In addition, the LVFX treatment resulted in a dose-dependent decrease in the level of 8-hydroxy-2'-deoxyguanosine (a marker of oxidative stress) and nitrotyrosine (a nitrative marker) in the lungs of virus-infected mice, and the nitrite/nitrate ratio (NO metabolites) and IFN-γ in BALF. These results indicate that LVFX may be of substantial benefit in the treatment of various acute inflammatory disorders such as influenza virus-induced pneumonia, by inhibiting inflammatory cell responses and suppressing the overproduction of NO in the lungs. PMID:26086073

  14. Pleiotropic Effects of Levofloxacin, Fluoroquinolone Antibiotics, against Influenza Virus-Induced Lung Injury

    PubMed Central

    Enoki, Yuki; Ishima, Yu; Tanaka, Ryota; Sato, Keizo; Kimachi, Kazuhiko; Shirai, Tatsuya; Watanabe, Hiroshi; Chuang, Victor T. G.; Fujiwara, Yukio; Takeya, Motohiro; Otagiri, Masaki; Maruyama, Toru

    2015-01-01

    Reactive oxygen species (ROS) and nitric oxide (NO) are major pathogenic molecules produced during viral lung infections, including influenza. While fluoroquinolones are widely used as antimicrobial agents for treating a variety of bacterial infections, including secondary infections associated with the influenza virus, it has been reported that they also function as anti-oxidants against ROS and as a NO regulator. Therefore, we hypothesized that levofloxacin (LVFX), one of the most frequently used fluoroquinolone derivatives, may attenuate pulmonary injuries associated with influenza virus infections by inhibiting the production of ROS species such as hydroxyl radicals and neutrophil-derived NO that is produced during an influenza viral infection. The therapeutic impact of LVFX was examined in a PR8 (H1N1) influenza virus-induced lung injury mouse model. ESR spin-trapping experiments indicated that LVFX showed scavenging activity against neutrophil-derived hydroxyl radicals. LVFX markedly improved the survival rate of mice that were infected with the influenza virus in a dose-dependent manner. In addition, the LVFX treatment resulted in a dose-dependent decrease in the level of 8-hydroxy-2’-deoxyguanosine (a marker of oxidative stress) and nitrotyrosine (a nitrative marker) in the lungs of virus-infected mice, and the nitrite/nitrate ratio (NO metabolites) and IFN-γ in BALF. These results indicate that LVFX may be of substantial benefit in the treatment of various acute inflammatory disorders such as influenza virus-induced pneumonia, by inhibiting inflammatory cell responses and suppressing the overproduction of NO in the lungs. PMID:26086073

  15. Inhibition of Pim1 kinase, new therapeutic approach in virus-induced asthma exacerbations.

    PubMed

    Vries, Maaike de; Bedke, Nicole; Smithers, Natalie P; Loxham, Matthew; Howarth, Peter H; Nawijn, Martijn C; Davies, Donna E

    2016-03-01

    Therapeutic options to treat virus-induced asthma exacerbations are limited and urgently needed. Therefore, we tested Pim1 kinase as potential therapeutic target in human rhinovirus (HRV) infections. We hypothesised that inhibition of Pim1 kinase reduces HRV replication by augmenting the interferon-induced anti-viral response due to increased activity of the janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway.Air-liquid interface (ALI) cultures of primary bronchial epithelial cells (PBECs) from healthy individuals and moderate-to-severe asthmatic volunteers were infected with HRV-16 with or without a specific Pim1 inhibitor; viral replication and induction of anti-viral responses were measured using RT-qPCR. Viral titres were measured by 50% tissue culture infective dose and release of interferon-γ-induced protein 10 (IP-10) and RANTES protein assessed by ELISA. Phosphorylation of STAT-1 was determined using western blotting.Viral replication was reduced in ALI cultures of healthy and asthmatic PBECs treated with the Pim1 inhibitor. Using cultures from healthy donors, enhanced STAT-1 phosphorylation upon inhibition of Pim1 kinase activity resulted in increased mRNA expression of interferon-β, interleukin-29, IP-10 and RANTES 12 h after infection and increased protein levels of IP-10 and RANTES 24 h after infection.We have identified Pim1 kinase as novel target to reduce viral replication in ALI cultures of PBECs. This may open new avenues for therapeutic interventions in virus-induced asthma exacerbations. PMID:26869670

  16. Novel Strategy To Protect against Influenza Virus-Induced Pneumococcal Disease without Interfering with Commensal Colonization.

    PubMed

    Greene, Christopher J; Marks, Laura R; Hu, John C; Reddinger, Ryan; Mandell, Lorrie; Roche-Hakansson, Hazeline; King-Lyons, Natalie D; Connell, Terry D; Hakansson, Anders P

    2016-06-01

    Streptococcus pneumoniae commonly inhabits the nasopharynx as a member of the commensal biofilm. Infection with respiratory viruses, such as influenza A virus, induces commensal S. pneumoniae to disseminate beyond the nasopharynx and to elicit severe infections of the middle ears, lungs, and blood that are associated with high rates of morbidity and mortality. Current preventive strategies, including the polysaccharide conjugate vaccines, aim to eliminate asymptomatic carriage with vaccine-type pneumococci. However, this has resulted in serotype replacement with, so far, less fit pneumococcal strains, which has changed the nasopharyngeal flora, opening the niche for entry of other virulent pathogens (e.g., Streptococcus pyogenes, Staphylococcus aureus, and potentially Haemophilus influenzae). The long-term effects of these changes are unknown. Here, we present an attractive, alternative preventive approach where we subvert virus-induced pneumococcal disease without interfering with commensal colonization, thus specifically targeting disease-causing organisms. In that regard, pneumococcal surface protein A (PspA), a major surface protein of pneumococci, is a promising vaccine target. Intradermal (i.d.) immunization of mice with recombinant PspA in combination with LT-IIb(T13I), a novel i.d. adjuvant of the type II heat-labile enterotoxin family, elicited strong systemic PspA-specific IgG responses without inducing mucosal anti-PspA IgA responses. This response protected mice from otitis media, pneumonia, and septicemia and averted the cytokine storm associated with septic infection but had no effect on asymptomatic colonization. Our results firmly demonstrated that this immunization strategy against virally induced pneumococcal disease can be conferred without disturbing the desirable preexisting commensal colonization of the nasopharynx. PMID:27001538

  17. Pathogenesis of influenza virus-induced pneumonia: involvement of both nitric oxide and oxygen radicals.

    PubMed Central

    Akaike, T; Noguchi, Y; Ijiri, S; Setoguchi, K; Suga, M; Zheng, Y M; Dietzschold, B; Maeda, H

    1996-01-01

    The role of nitric oxide (NO) in the pathogenesis of influenza virus-induced pneumonia in mice was investigated. Experimental influenza virus pneumonia was produced with influenza virus A/Kumamoto/Y5/67(H2N2). Both the enzyme activity of NO synthase (NOS) and mRNA expression of the inducible NOS were greatly increased in the mouse lungs; increases were mediated by interferon gamma. Excessive production of NO in the virus-infected lung was studied further by using electron spin resonance (ESR) spectroscopy. In vivo spin trapping with dithiocarbamate-iron complexes indicated that a significant amount of NO was generated in the virus-infected lung. Furthermore, an NO-hemoglobin ESR signal appeared in the virus-infected lung, and formation of NO-hemoglobin was significantly increased by treatment with superoxide dismutase and was inhibited by N(omega)-monomethyl-L-arginine (L-NMMA) administration. Immunohistochemistry with a specific anti-nitrotyrosine antibody showed intense staining of alveolar phagocytic cells such as macrophages and neutrophils and of intraalveolar exudate in the virus-infected lung. These results strongly suggest formation of peroxynitrite in the lung through the reaction of NO with O2-, which is generated by alveolar phagocytic cells and xanthine oxidase. In addition, administration of L-NMMA resulted in significant improvement in the survival rate of virus-infected mice without appreciable suppression of their antiviral defenses. On the basis of these data, we conclude that NO together with O2- which forms more reactive peroxynitrite may be the most important pathogenic factors in influenza virus-induced pneumonia in mice. Images Fig. 1 Fig. 5 PMID:8637894

  18. Murine autoimmune oophoritis, epididymoorchitis, and gastritis induced by day 3 thymectomy. Immunopathology.

    PubMed Central

    Tung, K. S.; Smith, S.; Teuscher, C.; Cook, C.; Anderson, R. E.

    1987-01-01

    (C57BL/6 X A/J) F1, (SWR/J X A/J) F1 and BALB/cBy mice, thymectomized on Day 3 (D3TX) or Day 7 (D7TX) or sham thymectomized (STX), were studied for immunopathologic changes in the ovary, testis, and gastric wall. In 95% of B6AF1, 100% of SWRAF1, and 35% of BALB/cBy mice ovarian disease developed, with onset at 5-6 weeks of age. Ovarian disease was not found in D7TX or STX mice. In D3TX mice, it was associated with mononuclear infiltration and ovarian follicle destruction, leading to atrophy. Epididymovasitis was detected in 70-90% of SWRAF1, 50% of B6AF1, and 64% of BALB/cBy mice after D3TX; whereas orchitis occurred in about 20% of SWRAF1 and B6AF1 mice. In some mice epididymovasitis also developed after D7TX, but not after STX. In contrast to the negative immunohistochemical findings in diseased ovaries, typical immune complex-like deposits of mouse IgG were detected by immunofluorescence along the basement membrane of epididymal ducts and seminiferous tubules. However, maximum incidence of epididymitis preceded immune complex detection. Gastritis developed in both female (57%) and male (50%) BALB/cBy mice after D3TX, occasionally after D7TX, but not after STX. Gastric mucosa was hypertrophic with dilated glands and heavy lymphocytic infiltrations throughout all gastric layers. BALB/cBy mice with gastritis usually did not have disease in the gonads, and vice versa. This study, therefore, confirms and extends the findings of Nishizuka and colleagues. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:3548402

  19. Unique role for ATG5 in neutrophil-mediated immunopathology during M. tuberculosis infection.

    PubMed

    Kimmey, Jacqueline M; Huynh, Jeremy P; Weiss, Leslie A; Park, Sunmin; Kambal, Amal; Debnath, Jayanta; Virgin, Herbert W; Stallings, Christina L

    2015-12-24

    Mycobacterium tuberculosis, a major global health threat, replicates in macrophages in part by inhibiting phagosome-lysosome fusion, until interferon-γ (IFNγ) activates the macrophage to traffic M. tuberculosis to the lysosome. How IFNγ elicits this effect is unknown, but many studies suggest a role for macroautophagy (herein termed autophagy), a process by which cytoplasmic contents are targeted for lysosomal degradation. The involvement of autophagy has been defined based on studies in cultured cells where M. tuberculosis co-localizes with autophagy factors ATG5, ATG12, ATG16L1, p62, NDP52, BECN1 and LC3 (refs 2-6), stimulation of autophagy increases bacterial killing, and inhibition of autophagy increases bacterial survival. Notably, these studies reveal modest (~1.5-3-fold change) effects on M. tuberculosis replication. By contrast, mice lacking ATG5 in monocyte-derived cells and neutrophils (polymorponuclear cells, PMNs) succumb to M. tuberculosis within 30 days, an extremely severe phenotype similar to mice lacking IFNγ signalling. Importantly, ATG5 is the only autophagy factor that has been studied during M. tuberculosis infection in vivo and autophagy-independent functions of ATG5 have been described. For this reason, we used a genetic approach to elucidate the role for multiple autophagy-related genes and the requirement for autophagy in resistance to M. tuberculosis infection in vivo. Here we show that, contrary to expectation, autophagic capacity does not correlate with the outcome of M. tuberculosis infection. Instead, ATG5 plays a unique role in protection against M. tuberculosis by preventing PMN-mediated immunopathology. Furthermore, while Atg5 is dispensable in alveolar macrophages during M. tuberculosis infection, loss of Atg5 in PMNs can sensitize mice to M. tuberculosis. These findings shift our understanding of the role of ATG5 during M. tuberculosis infection, reveal new outcomes of ATG5 activity, and shed light on early events in innate

  20. Multiple Inhibitory Pathways Contribute to Lung CD8+ T Cell Impairment and Protect against Immunopathology during Acute Viral Respiratory Infection.

    PubMed

    Erickson, John J; Rogers, Meredith C; Tollefson, Sharon J; Boyd, Kelli L; Williams, John V

    2016-07-01

    Viruses are frequent causes of lower respiratory infection (LRI). Programmed cell death-1 (PD-1) signaling contributes to pulmonary CD8(+) T cell (TCD8) functional impairment during acute viral LRI, but the role of TCD8 impairment in viral clearance and immunopathology is unclear. We now find that human metapneumovirus infection induces virus-specific lung TCD8 that fail to produce effector cytokines or degranulate late postinfection, with minimally increased function even in the absence of PD-1 signaling. Impaired lung TCD8 upregulated multiple inhibitory receptors, including PD-1, lymphocyte activation gene 3 (LAG-3), T cell Ig mucin 3, and 2B4. Moreover, coexpression of these receptors continued to increase even after viral clearance, with most virus-specific lung TCD8 expressing three or more inhibitory receptors on day 14 postinfection. Viral infection also increased expression of inhibitory ligands by both airway epithelial cells and APCs, further establishing an inhibitory environment. In vitro Ab blockade revealed that multiple inhibitory receptors contribute to TCD8 impairment induced by either human metapneumovirus or influenza virus infection. In vivo blockade of T cell Ig mucin 3 signaling failed to enhance TCD8 function or reduce viral titers. However, blockade of LAG-3 in PD-1-deficient mice restored TCD8 effector functions but increased lung pathology, indicating that LAG-3 mediates lung TCD8 impairment in vivo and contributes to protection from immunopathology during viral clearance. These results demonstrate that an orchestrated network of pathways modifies lung TCD8 functionality during viral LRI, with PD-1 and LAG-3 serving prominent roles. Lung TCD8 impairment may prevent immunopathology but also contributes to recurrent lung infections. PMID:27259857

  1. Virus-lymphocyte interaction: T cells of the helper subset are infected with lymphocytic choriomeningitis virus during persistent infection in vivo.

    PubMed Central

    Ahmed, R; King, C C; Oldstone, M B

    1987-01-01

    The lifelong persistence of lymphocytic choriomeningitis virus (LCMV) in neonatally or congenitally infected mice is accompanied by a suppression of virus-specific T-cell responses. In this study, we identified the subset of T cells infected with LCMV during persistent infection in vivo. Using specific monoclonal antibodies to separate the different lymphocyte cell populations and employing both an infectious center assay and immunofluorescence to detect the virus, we found that infection is confined primarily to T cells of the helper subset (L3T4+ Lyt2-), with minimal involvement of cytotoxic T cells (Lyt2+ L3T4-) and mature B cells. About 0.54 to 1.1% of L3T4+ T cells were producing the virus, as determined by the infectious center assay. In contrast, 9.1 to 12.2% of these L3T4+ T cells contained viral antigen, as shown by immunofluorescence studies. This finding suggested that, at any given time, a substantial number of infected T cells were not producing infectious virus. This infection of T helper cells may be involved in the suppression of LCMV-specific T-cell responses observed in persistently infected mice. Images PMID:2952807

  2. Lymphocytic Choriomeningitis Virus Expands a Population of NKG2D+CD8+ T Cells That Exacerbates Disease in Mice Coinfected with Leishmania major.

    PubMed

    Crosby, Erika J; Clark, Megan; Novais, Fernanda O; Wherry, E John; Scott, Phillip

    2015-10-01

    Leishmaniasis is a significant neglected tropical disease that is associated with a wide range of clinical presentations and a lifelong persistent infection. Because of the chronic nature of the disease, there is a high risk for coinfection occurring in patients, and how coinfections influence the outcome of leishmaniasis is poorly understood. To address this issue, we infected mice with Leishmania major and 2 wk later with lymphocytic choriomeningitis virus (LCMV) and then monitored the course of infection. Leishmania parasites are controlled by production of IFN-γ, which leads to macrophage-mediated parasite killing. Thus, one might predict that coinfection with LCMV, which induces a strong systemic type 1 response, would accelerate disease resolution. However, we found that infection with LCMV led to significantly enhanced disease in L. major-infected animals. This increased disease correlated with an infiltration into the leishmanial lesions of NKG2D(+) CD8(+) T cells producing granzyme B, but surprisingly little IFN-γ. We found that depletion of CD8 T cells after viral clearance, as well as blockade of NKG2D, reversed the increased pathology seen in coinfected mice. Thus, this work highlights the impact a secondary infection can have on leishmaniasis and demonstrates that even pathogens known to promote a type 1 response may exacerbate leishmanial infections. PMID:26290604

  3. Rapid activation of spleen dendritic cell subsets following lymphocytic choriomeningitis virus infection of mice: analysis of the involvement of type 1 IFN.

    PubMed

    Montoya, Maria; Edwards, Matthew J; Reid, Delyth M; Borrow, Persephone

    2005-02-15

    In this study, we report the dynamic changes in activation and functions that occur in spleen dendritic cell (sDC) subsets following infection of mice with a natural murine pathogen, lymphocytic choriomeningitis virus (LCMV). Within 24 h postinfection (pi), sDCs acquired the ability to stimulate naive LCMV-specific CD8+ T cells ex vivo. Conventional (CD11chigh CD8+ and CD4+) sDC subsets rapidly up-regulated expression of costimulatory molecules and began to produce proinflammatory cytokines. Their tendency to undergo apoptosis ex vivo simultaneously increased, and in vivo the number of conventional DCs in the spleen decreased markedly, dropping approximately 2-fold by day 3 pi. Conversely, the number of plasmacytoid (CD11clowB220+) DCs in the spleen increased, so that they constituted almost 40% of sDCs by day 3 pi. Type 1 IFN production was up-regulated in plasmacytoid DCs by 24 h pi. Analysis of DC activation and maturation in mice unable to respond to type 1 IFNs implicated these cytokines in driving infection-associated phenotypic activation of conventional DCs and their enhanced tendency to undergo apoptosis, but also indicated the existence of type 1 IFN-independent pathways for the functional maturation of DCs during LCMV infection. PMID:15699111

  4. A novel PRD I and TG binding activity involved in virus-induced transcription of IFN-A genes.

    PubMed Central

    Génin, P; Bragança, J; Darracq, N; Doly, J; Civas, A

    1995-01-01

    Comparative analysis of the inducible elements of the mouse interferon A4 and A11 gene promoters (IE-A4 and IE-A11) by transient transfection experiments, DNase 1 footprinting and electrophoretic mobility shift assays resulted in identification of a virus-induced binding activity suggested to be involved in NDV-induced activation of transcription of these genes. The virus-induced factor, termed VIF, is activated early by contact of virions with cells. It specifically recognizes the PRD I-like domain shared by both inducible elements, as well as the TG-like domain of IE-A4. This factor, distinct from the IRF-1, IRF-2 and the alpha F1 binding proteins and presenting a different affinity pattern from that of the TG protein, is proposed as a candidate for IFN-type I gene regulation. Images PMID:8559665

  5. Prevention of Herpes Simplex Virus Induced Stromal Keratitis by a Glycoprotein B-Specific Monoclonal Antibody

    PubMed Central

    Krawczyk, Adalbert; Dirks, Miriam; Kasper, Maren; Buch, Anna; Dittmer, Ulf; Giebel, Bernd; Wildschütz, Lena; Busch, Martin; Goergens, Andre; Schneweis, Karl E.; Eis-Hübinger, Anna M.; Sodeik, Beate; Heiligenhaus, Arnd; Roggendorf, Michael; Bauer, Dirk

    2015-01-01

    The increasing incidence of acyclovir (ACV) and multidrug-resistant strains in patients with corneal HSV-1 infections leading to Herpetic Stromal Keratitis (HSK) is a major health problem in industrialized countries and often results in blindness. To overcome this obstacle, we have previously developed an HSV-gB-specific monoclonal antibody (mAb 2c) that proved to be highly protective in immunodeficient NOD/SCID-mice towards genital infections. In the present study, we examined the effectivity of mAb 2c in preventing the immunopathological disease HSK in the HSK BALB/c mouse model. Therefore, mice were inoculated with HSV-1 strain KOS on the scarified cornea to induce HSK and subsequently either systemically or topically treated with mAb 2c. Systemic treatment was performed by intravenous administration of mAb 2c 24 h prior to infection (pre-exposure prophylaxis) or 24, 40, and 56 hours after infection (post-exposure immunotherapy). Topical treatment was performed by periodical inoculations (5 times per day) of antibody-containing eye drops as control, starting at 24 h post infection. Systemic antibody treatment markedly reduced viral loads at the site of infection and completely protected mice from developing HSK. The administration of the antiviral antibody prior or post infection was equally effective. Topical treatment had no improving effect on the severity of HSK. In conclusion, our data demonstrate that mAb 2c proved to be an excellent drug for the treatment of corneal HSV-infections and for prevention of HSK and blindness. Moreover, the humanized counterpart (mAb hu2c) was equally effective in protecting mice from HSV-induced HSK when compared to the parental mouse antibody. These results warrant the future development of this antibody as a novel approach for the treatment of corneal HSV-infections in humans. PMID:25587898

  6. Virus-induced gene silencing of fiber-related genes in cotton.

    PubMed

    Tuttle, John R; Haigler, Candace H; Robertson, Dominique Niki

    2015-01-01

    Virus-Induced Gene Silencing (VIGS) is a useful method for transient downregulation of gene expression in crop plants. The geminivirus Cotton leaf crumple virus (CLCrV) has been modified to serve as a VIGS vector for persistent gene silencing in cotton. Here the use of Green Fluorescent Protein (GFP) is described as a marker for identifying silenced tissues in reproductive tissues, a procedure that requires the use of transgenic plants. Suggestions are given for isolating and cloning combinations of target and marker sequences so that the total length of inserted foreign DNA is between 500 and 750 bp. Using this strategy, extensive silencing is achieved with only 200-400 bp of sequence homologous to an endogenous gene, reducing the possibility of off-target silencing. Cotyledons can be inoculated using either the gene gun or Agrobacterium and will continue to show silencing throughout fruit and fiber development. CLCrV is not transmitted through seed, and VIGS is limited to genes expressed in the maternally derived seed coat and fiber in the developing seed. This complicates the use of GFP as a marker for VIGS because cotton fibers must be separated from unsilenced tissue in the seed to determine if they are silenced. Nevertheless, fibers from a large number of seeds can be rapidly screened following placement into 96-well plates. Methods for quantifying the extent of silencing using semiquantitative RT-PCR are given. PMID:25740368

  7. Disruption of Rpp1-mediated soybean rust immunity by virus-induced gene silencing

    PubMed Central

    Cooper, Bret; Campbell, Kimberly B; McMahon, Michael B; Luster, Douglas G

    2013-01-01

    Phakopsora pachyrhizi, a fungus that causes rust disease on soybean, has potential to impart significant yield loss and disrupt food security and animal feed production. Rpp1 is a soybean gene that confers immunity to soybean rust, and it is important to understand how it regulates the soybean defense system and to use this knowledge to protect commercial crops. It was previously discovered that some soybean proteins resembling transcription factors accumulate in the nucleus of Rpp1 soybeans. To determine if they contribute to immunity, Bean pod mottle virus was used to attenuate or silence the expression of their genes. Rpp1 plants subjected to virus-induced gene silencing exhibited reduced amounts of RNA for 5 of the tested genes, and the plants developed rust-like symptoms after subsequent inoculation with fungal spores. Symptoms were associated with the accumulation of rust fungal RNA and protein. Silenced plants also had reduced amounts of RNA for the soybean Myb84 transcription factor and soybean isoflavone O-methyltransferase, both of which are important to phenylpropanoid biosynthesis and lignin formation, crucial components of rust resistance. These results help resolve some of the genes that contribute to Rpp1-mediated immunity and improve upon the knowledge of the soybean defense system. It is possible that these genes could be manipulated to enhance rust resistance in otherwise susceptible soybean cultivars. PMID:24401541

  8. Method: low-cost delivery of the cotton leaf crumple virus-induced gene silencing system

    PubMed Central

    2012-01-01

    Background We previously developed a virus-induced gene silencing (VIGS) vector for cotton from the bipartite geminivirusCotton leaf crumple virus (CLCrV). The original CLCrV VIGS vector was designed for biolistic delivery by a gene gun. This prerequisite limited the use of the system to labs with access to biolistic equipment. Here we describe the adaptation of this system for delivery by Agrobacterium (Agrobacterium tumefaciens). We also describe the construction of two low-cost particle inflow guns. Results The biolistic CLCrV vector was transferred into two Agrobacterium binary plasmids. Agroinoculation of the binary plasmids into cotton resulted in silencing and GFP expression comparable to the biolistic vector. Two homemade low-cost gene guns were used to successfully inoculate cotton (G. hirsutum) and N. benthamiana with either the CLCrV VIGS vector or the Tomato golden mosaic virus (TGMV) VIGS vector respectively. Conclusions These innovations extend the versatility of CLCrV-based VIGS for analyzing gene function in cotton. The two low-cost gene guns make VIGS experiments affordable for both research and teaching labs by providing a working alternative to expensive commercial gene guns. PMID:22853641

  9. Autophagy Genes Enhance Murine Gammaherpesvirus 68 Reactivation from Latency by Preventing Virus-Induced Systemic Inflammation.

    PubMed

    Park, Sunmin; Buck, Michael D; Desai, Chandni; Zhang, Xin; Loginicheva, Ekaterina; Martinez, Jennifer; Freeman, Michael L; Saitoh, Tatsuya; Akira, Shizuo; Guan, Jun-Lin; He, You-Wen; Blackman, Marcia A; Handley, Scott A; Levine, Beth; Green, Douglas R; Reese, Tiffany A; Artyomov, Maxim N; Virgin, Herbert W

    2016-01-13

    Host genes that regulate systemic inflammation upon chronic viral infection are incompletely understood. Murine gammaherpesvirus 68 (MHV68) infection is characterized by latency in macrophages, and reactivation is inhibited by interferon-γ (IFN-γ). Using a lysozyme-M-cre (LysMcre) expression system, we show that deletion of autophagy-related (Atg) genes Fip200, beclin 1, Atg14, Atg16l1, Atg7, Atg3, and Atg5, in the myeloid compartment, inhibited MHV68 reactivation in macrophages. Atg5 deficiency did not alter reactivation from B cells, and effects on reactivation from macrophages were not explained by alterations in productive viral replication or the establishment of latency. Rather, chronic MHV68 infection triggered increased systemic inflammation, increased T cell production of IFN-γ, and an IFN-γ-induced transcriptional signature in macrophages from Atg gene-deficient mice. The Atg5-related reactivation defect was partially reversed by neutralization of IFN-γ. Thus Atg genes in myeloid cells dampen virus-induced systemic inflammation, creating an environment that fosters efficient MHV68 reactivation from latency. PMID:26764599

  10. Common Viral Integration Sites Identified in Avian Leukosis Virus-Induced B-Cell Lymphomas

    PubMed Central

    Justice, James F.; Morgan, Robin W.

    2015-01-01

    ABSTRACT Avian leukosis virus (ALV) induces B-cell lymphoma and other neoplasms in chickens by integrating within or near cancer genes and perturbing their expression. Four genes—MYC, MYB, Mir-155, and TERT—have previously been identified as common integration sites in these virus-induced lymphomas and are thought to play a causal role in tumorigenesis. In this study, we employ high-throughput sequencing to identify additional genes driving tumorigenesis in ALV-induced B-cell lymphomas. In addition to the four genes implicated previously, we identify other genes as common integration sites, including TNFRSF1A, MEF2C, CTDSPL, TAB2, RUNX1, MLL5, CXorf57, and BACH2. We also analyze the genome-wide ALV integration landscape in vivo and find increased frequency of ALV integration near transcriptional start sites and within transcripts. Previous work has shown ALV prefers a weak consensus sequence for integration in cultured human cells. We confirm this consensus sequence for ALV integration in vivo in the chicken genome. PMID:26670384

  11. Development of Virus-Induced Gene Expression and Silencing Vector Derived from Grapevine Algerian Latent Virus.

    PubMed

    Park, Sang-Ho; Choi, Hoseong; Kim, Semin; Cho, Won Kyong; Kim, Kook-Hyung

    2016-08-01

    Grapevine Algerian latent virus (GALV) is a member of the genus Tombusvirus in the Tombusviridae and infects not only woody perennial grapevine plant but also herbaceous Nicotiana benthamiana plant. In this study, we developed GALV-based gene expression and virus-induced gene silencing (VIGS) vectors in N. benthamiana. The GALV coat protein deletion vector, pGMG, was applied to express the reporter gene, green fluorescence protein (GFP), but the expression of GFP was not detected due to the necrotic cell death on the infiltrated leaves. The p19 silencing suppressor of GALV was engineered to inactivate its expression and GFP was successfully expressed with unrelated silencing suppressor, HC-Pro, from soybean mosaic virus. The pGMG vector was used to knock down magnesium chelatase (ChlH) gene in N. benthamaina and the silencing phenotype was clearly observed on systemic leaves. Altogether, the GALV-derived vector is expected to be an attractive tool for useful gene expression and VIGS vectors in grapevine as well as N. benthamiana. PMID:27493613

  12. A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize1[OPEN

    PubMed Central

    Mei, Yu; Kernodle, Bliss M.; Hill, John H.

    2016-01-01

    Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. PMID:27208311

  13. Virus-induced gene silencing in Catharanthus roseus by biolistic inoculation of tobacco rattle virus vectors.

    PubMed

    Carqueijeiro, I; Masini, E; Foureau, E; Sepúlveda, L J; Marais, E; Lanoue, A; Besseau, S; Papon, N; Clastre, M; Dugé de Bernonville, T; Glévarec, G; Atehortùa, L; Oudin, A; Courdavault, V

    2015-11-01

    Catharanthus roseus constitutes the unique source of several valuable monoterpenoid indole alkaloids, including the antineoplastics vinblastine and vincristine. These alkaloids result from a complex biosynthetic pathway encompassing between 30 and 50 enzymatic steps whose characterisation is still underway. The most recent identifications of genes from this pathway relied on a tobacco rattle virus-based virus-induced gene silencing (VIGS) approach, involving an Agrobacterium-mediated inoculation of plasmids encoding the two genomic components of the virus. As an alternative, we developed a biolistic-mediated approach of inoculation of virus-encoding plasmids that can be easily performed by a simple bombardment of young C. roseus plants. After optimisation of the transformation conditions, we showed that this approach efficiently silenced the phytoene desaturase gene, leading to strong and reproducible photobleaching of leaves. This biolistic transformation was also used to silence a previously characterised gene from the alkaloid biosynthetic pathway, encoding iridoid oxidase. Plant bombardment caused down-regulation of the targeted gene (70%), accompanied by a correlated decreased in MIA biosynthesis (45-90%), similar to results obtained via agro-transformation. Thus, the biolistic-based VIGS approach developed for C. roseus appears suitable for gene function elucidation and can readily be used instead of the Agrobacterium-based approach, e.g. when difficulties arise with agro-inoculations or when Agrobacterium-free procedures are required to avoid plant defence responses. PMID:26284695

  14. A virus-induced gene silencing approach to understanding alkaloid metabolism in Catharanthus roseus

    PubMed Central

    Liscombe, David K.; O’Connor, Sarah E.

    2011-01-01

    The anticancer agents vinblastine and vincristine are bisindole alkaloids derived from coupling vindoline and catharanthine, monoterpenoid indole alkaloids produced exclusively by Madagascar periwinkle (Catharanthus roseus) plants. Industrial production of vinblastine and vincristine currently relies on isolation from C. roseus leaves, a process that affords these compounds in 0.0003–0.01% yields. Metabolic engineering efforts to improve alkaloid content or provide alternative sources of the bisindole alkaloids ultimately rely on the isolation and characterization of the genes involved. Several vindoline biosynthetic genes have been isolated, and the cellular and subcellular organization of the corresponding enzymes has been well studied. However, due to the leaf-specific localization of vindoline biosynthesis, and the lack of production of this precursor in cell suspension and hairy root cultures of C. roseus, further elucidation of this pathway demands the development of reverse genetics approaches to assay gene function in planta. The bipartite pTRV vector system is a Tobacco Rattle Virus-based virus-induced gene silencing (VIGS) platform that has provided efficient and effective means to assay gene function in diverse plant systems. We have developed a VIGS method to investigate gene function in C. roseus plants using the pTRV vector system. The utility of this approach in understanding gene function in C. roseus leaves is demonstrated by silencing known vindoline biosynthetic genes previously characterized in vitro. PMID:21802100

  15. Virus-induced gene silencing for comparative functional studies in Gladiolus hybridus.

    PubMed

    Zhong, Xionghui; Yuan, Xue; Wu, Ze; Khan, Muhammad Ali; Chen, Jin; Li, Xiaoxin; Gong, Benhe; Zhao, Yang; Wu, Jian; Wu, Chenyu; Yi, Mingfang

    2014-02-01

    Functional analysis of genes in gladiolus has previously been impractical due to the lack of an efficient stable genetic transformation method. However, virus-induced gene silencing (VIGS) is effective in some plants which are difficult to transform through other methods. Although the Tobacco rattle virus (TRV)-based VIGS system has been developed and used for verifying gene functions in diverse plants, an appropriate TRV-VIGS approach for gladiolus has not been established yet. In this report we describe the first use of the TRV-VIGS system for gene silencing in gladiolus. Vacuum infiltration of cormels and young plants with the GhPDS-VIGS vector effectively down-regulated the PHYTOENE DESATURASE ortholog GhPDS gene and also resulted in various degrees of photobleaching in Gladiolus hybridus. The reduction in GhPDS expression was tested after TRV-based vector infection using real-time RT-PCR. In addition, the progress of TRV infection was detected by fluorescence visualization using a pTRV2: CP-GFP vector. In conclusion, the TRV-mediated VIGS described here will be an effective gene function analysis mechanism in gladiolus. PMID:24170343

  16. Development of Virus-Induced Gene Expression and Silencing Vector Derived from Grapevine Algerian Latent Virus

    PubMed Central

    Park, Sang-Ho; Choi, Hoseong; Kim, Semin; Cho, Won Kyong; Kim, Kook-Hyung

    2016-01-01

    Grapevine Algerian latent virus (GALV) is a member of the genus Tombusvirus in the Tombusviridae and infects not only woody perennial grapevine plant but also herbaceous Nicotiana benthamiana plant. In this study, we developed GALV-based gene expression and virus-induced gene silencing (VIGS) vectors in N. benthamiana. The GALV coat protein deletion vector, pGMG, was applied to express the reporter gene, green fluorescence protein (GFP), but the expression of GFP was not detected due to the necrotic cell death on the infiltrated leaves. The p19 silencing suppressor of GALV was engineered to inactivate its expression and GFP was successfully expressed with unrelated silencing suppressor, HC-Pro, from soybean mosaic virus. The pGMG vector was used to knock down magnesium chelatase (ChlH) gene in N. benthamaina and the silencing phenotype was clearly observed on systemic leaves. Altogether, the GALV-derived vector is expected to be an attractive tool for useful gene expression and VIGS vectors in grapevine as well as N. benthamiana. PMID:27493613

  17. Theiler's murine encephalomyelitis virus-induced cardiac and skeletal muscle disease.

    PubMed Central

    Gómez, R M; Rinehart, J E; Wollmann, R; Roos, R P

    1996-01-01

    The DA strain of Theiler's murine encephalomyelitis virus, a member of the cardiovirus genus of picornaviruses, induces a restricted and persistent infection associated with a demyelinating process following intracerebral inoculation of mice; both virus infection and the immune response are believed to contribute to the late white matter disease. We now report that intraperitoneal inoculation with DA produces an acute myositis that progresses to a chronic inflammatory muscle disease in CD-1 mice as well as several inbred mouse strains. Some mouse strains also develop central nervous system white matter disease and a focal myocarditis. Infectious virus in skeletal muscle falls to undetectable levels 3 weeks postinoculation (p.i.), although viral genome persists for at least 12 weeks p.i., the longest period of observation. Severe combined immunodeficient animals have evidence of muscle pathology as long as 5 weeks p.i., suggesting that DA virus is capable of inducing chronic muscle disease in the absence of an immune response. The presence in immunocompetent mice, however, of prominent muscle inflammation in the absence of infectious virus suggests that the immune system also contributes to the pathology. T lymphocytes are the predominant cell type infiltrating the skeletal muscle during the chronic disease. This murine model may further our understanding of virus-induced chronic myositis and help to clarify the pathogenesis of human inflammatory myopathies. PMID:8971022

  18. Non-targeted effects of virus-induced gene silencing vectors on host endogenous gene expression.

    PubMed

    Oláh, Enikő; Pesti, Réka; Taller, Dénes; Havelda, Zoltán; Várallyay, Éva

    2016-09-01

    Virus-induced gene silencing (VIGS) uses recombinant viruses to study gene function; however, the effect of the virus vector itself on the gene expression of the host is not always considered. In our work, we investigated non-targeted gene expression changes of the host in order to see how often these changes appear. Effects of various VIGS vector infections were analysed by monitoring gene expression levels of housekeeping genes by Northern blot analysis in four different hosts. We found that non-targeted changes happens very often. More importantly, these non-targeted effects can cause drastic changes in the gene-expression pattern of host genes that are usually used as references in these studies. We have also found that in a tobacco rattle virus (TRV)-based VIGS, the presence of foreign sequences in the cloning site of the vector can also have a non-targeted effect, and even the use of an internal control can lead to unpredicted changes. Our results show that although VIGS is a very powerful technique, the VIGS vector, as a pathogen of the host, can cause unwanted changes in its gene-expression pattern, highlighting the importance of careful selection of both the genes to be tested and those to be used as references in the planned experiments. PMID:27283101

  19. Inflammatory cytokine-mediated evasion of virus-induced tumors from NK cell control

    PubMed Central

    Mishra, Rabinarayan; Polic, Bojan; Welsh, Raymond M.; Szomolanyi-Tsuda, Eva

    2013-01-01

    Infections with DNA tumor viruses, including members of the polyomavirus family, often result in tumor formation in immune-deficient hosts. The complex control involved in antiviral and antitumor immune responses during these infections can be studied in murine polyomavirus (PyV)-infected mice as a model. We found that NK cells efficiently kill cells derived from PyV-induced salivary gland tumors in vitro in an NKG2D (effector cell) -RAE-1 (target cell) - dependent manner, but in T cell-deficient mice NK cells only delay but do not prevent the development of PyV-induced tumors. Here we show that the PyV-induced tumors have infiltrating functional NK cells. The freshly removed tumors, however, lack surface RAE-1 expression, and the tumor tissues produce soluble factors that down-regulate RAE-1. These factors include the pro-inflammatory cytokines IL-1α, IL-1β, IL-33, and TNF. Each of these cytokines down-regulate RAE-1 expression and susceptibility to NK cell mediated cytotoxicity. CD11b+F4/80+ macrophages infiltrating the PyV-induced tumors produce high amounts of IL-1β and TNF. Thus, our data suggest a new mechanism whereby inflammatory cytokines generated in the tumor environment lead to evasion of NK cell-mediated control of virus-induced tumors. PMID:23772039

  20. Applications and advantages of virus-induced gene silencing for gene function studies in plants.

    PubMed

    Burch-Smith, Tessa M; Anderson, Jeffrey C; Martin, Gregory B; Dinesh-Kumar, S P

    2004-09-01

    Virus-induced gene silencing (VIGS) is a recently developed gene transcript suppression technique for characterizing the function of plant genes. The approach involves cloning a short sequence of a targeted plant gene into a viral delivery vector. The vector is used to infect a young plant, and in a few weeks natural defense mechanisms of the plant directed at suppressing virus replication also result in specific degradation of mRNAs from the endogenous plant gene that is targeted for silencing. VIGS is rapid (3-4 weeks from infection to silencing), does not require development of stable transformants, allows characterization of phenotypes that might be lethal in stable lines, and offers the potential to silence either individual or multiple members of a gene family. Here we briefly review the discoveries that led to the development of VIGS and what is known about the experimental requirements for effective silencing. We describe the methodology of VIGS and how it can be optimized and used for both forward and reverse genetics studies. Advantages and disadvantages of VIGS compared with other loss-of-function approaches available for plants are discussed, along with how the limitations of VIGS might be overcome. Examples are reviewed where VIGS has been used to provide important new insights into the roles of specific genes in plant development and plant defense responses. Finally, we examine the future prospects for VIGS as a powerful tool for assessing and characterizing the function of plant genes. PMID:15315635

  1. Characterization of Chikungunya Virus Induced Host Response in a Mouse Model of Viral Myositis

    PubMed Central

    Dhanwani, Rekha; Khan, Mohsin; Lomash, Vinay; Rao, Putcha Venkata Lakshmana; Ly, Hinh; Parida, Manmohan

    2014-01-01

    While a number of studies have documented the persistent presence of chikungunya virus (CHIKV) in muscle tissue with primary fibroblast as the preferable cell target, little is known regarding the alterations that take place in muscle tissue in response to CHIKV infection. Hence, in the present study a permissive mouse model of CHIKV infection was established and characterized in order to understand the pathophysiology of the disease. The two dimensional electrophoresis of muscle proteome performed for differential analysis indicated a drastic reprogramming of the proteins from various classes like stress, inflammation, cytoskeletal, energy and lipid metabolism. The roles of the affected proteins were explained in relation to virus induced myopathy which was further supported by the histopathological and behavioural experiments proving the lack of hind limb coordination and other loco-motor abnormalities in the infected mice. Also, the level of various pro-inflammatory mediators like IL-6, MCP-1, Rantes and TNF-α was significantly elevated in muscles of infected mice. Altogether this comprehensive study of characterizing CHIKV induced mouse myopathy provides many potential targets for further evaluation and biomarker study. PMID:24667237

  2. A CRISPR-based screen identifies genes essential for West Nile virus-induced cell death

    PubMed Central

    Ma, Hongming; Dang, Ying; Wu, Yonggan; Jia, Gengxiang; Anaya, Edgar; Zhang, Junli; Abraham, Sojan; Choi, Jang-Gi; Shi, Guojun; Qi, Ling; Manjunath, N.; Wu, Haoquan

    2015-01-01

    Summary West Nile virus (WNV) causes an acute neurological infection attended by massive neuronal cell death. However, the mechanism(s) behind the virus-induced cell death is poorly understood. Using a library containing 77,406 sgRNAs targeting 20,121 genes, we performed a genome-wide screen followed by a second screen with a sub-library. Among the genes identified, seven genes, EMC2, EMC3, SEL1L, DERL2, UBE2G2, UBE2J1, and HRD1, stood out as having the strongest phenotype, whose knockout conferred strong protection against WNV-induced cell death with two different WNV strains and in three cell lines. Interestingly, knockout of these genes did not block WNV replication. Thus, these appear to be essential genes that link WNV replication to downstream cell death pathway(s). In addition, the fact that all of these genes belong to the endoplasmic reticulum-associated protein degradation (ERAD) pathway suggests that this might be the primary driver of WNV-induced cell death. PMID:26190106

  3. Foxtail Mosaic Virus-Induced Gene Silencing in Monocot Plants1[OPEN

    PubMed Central

    Liu, Na; Xie, Ke; Jia, Qi; Zhao, Jinping; Chen, Tianyuan; Li, Huangai; Wei, Xiang; Diao, Xianmin; Hong, Yiguo

    2016-01-01

    Virus-induced gene silencing (VIGS) is a powerful technique to study gene function in plants. However, very few VIGS vectors are available for monocot plants. Here we report that Foxtail mosaic virus (FoMV) can be engineered as an effective VIGS system to induce efficient silencing of endogenous genes in monocot plants including barley (Hordeum vulgare L.), wheat (Triticum aestivum) and foxtail millet (Setaria italica). This is evidenced by FoMV-based silencing of phytoene desaturase (PDS) and magnesium chelatase in barley, of PDS and Cloroplastos alterados1 in foxtail millet and wheat, and of an additional gene IspH in foxtail millet. Silencing of these genes resulted in photobleached or chlorosis phenotypes in barley, wheat, and foxtail millet. Furthermore, our FoMV-based gene silencing is the first VIGS system reported for foxtail millet, an important C4 model plant. It may provide an efficient toolbox for high-throughput functional genomics in economically important monocot crops. PMID:27225900

  4. A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize.

    PubMed

    Mei, Yu; Zhang, Chunquan; Kernodle, Bliss M; Hill, John H; Whitham, Steven A

    2016-06-01

    Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. PMID:27208311

  5. Delineation of autoantibody repertoire through differential proteogenomics in hepatitis C virus-induced cryoglobulinemia.

    PubMed

    Ogishi, Masato; Yotsuyanagi, Hiroshi; Moriya, Kyoji; Koike, Kazuhiko

    2016-01-01

    Antibodies cross-reactive to pathogens and autoantigens are considered pivotal in both infection control and accompanying autoimmunity. However, the pathogenic roles of autoantibodies largely remain elusive without a priori knowledge of disease-specific autoantigens. Here, through a novel quantitative proteogenomics approach, we demonstrated a successful identification of immunoglobulin variable heavy chain (VH) sequences highly enriched in pathological immune complex from clinical specimens obtained from a patient with hepatitis C virus-induced cryoglobulinemia (HCV-CG). Reconstructed single-domain antibodies were reactive to both HCV antigens and potentially liver-derived human proteins. Moreover, over the course of antiviral therapy, a substantial "de-evolution" of a distinct sub-repertoire was discovered, to which proteomically identified cryoprecipitation-prone autoantibodies belonged. This sub-repertoire was characterized by IGHJ6*03-derived, long, hydrophobic complementarity determining region (CDR-H3). This study provides a proof-of-concept of de novo mining of autoantibodies and corresponding autoantigen candidates in a disease-specific context in human, thus facilitating future reverse-translational research for the discovery of novel biomarkers and the development of antigen-specific immunotherapy against various autoantibody-related disorders. PMID:27403724

  6. Delineation of autoantibody repertoire through differential proteogenomics in hepatitis C virus-induced cryoglobulinemia

    PubMed Central

    Ogishi, Masato; Yotsuyanagi, Hiroshi; Moriya, Kyoji; Koike, Kazuhiko

    2016-01-01

    Antibodies cross-reactive to pathogens and autoantigens are considered pivotal in both infection control and accompanying autoimmunity. However, the pathogenic roles of autoantibodies largely remain elusive without a priori knowledge of disease-specific autoantigens. Here, through a novel quantitative proteogenomics approach, we demonstrated a successful identification of immunoglobulin variable heavy chain (VH) sequences highly enriched in pathological immune complex from clinical specimens obtained from a patient with hepatitis C virus-induced cryoglobulinemia (HCV-CG). Reconstructed single-domain antibodies were reactive to both HCV antigens and potentially liver-derived human proteins. Moreover, over the course of antiviral therapy, a substantial “de-evolution” of a distinct sub-repertoire was discovered, to which proteomically identified cryoprecipitation-prone autoantibodies belonged. This sub-repertoire was characterized by IGHJ6*03-derived, long, hydrophobic complementarity determining region (CDR-H3). This study provides a proof-of-concept of de novo mining of autoantibodies and corresponding autoantigen candidates in a disease-specific context in human, thus facilitating future reverse-translational research for the discovery of novel biomarkers and the development of antigen-specific immunotherapy against various autoantibody-related disorders. PMID:27403724

  7. Functional analyses of cellulose synthase genes in flax (Linum usitatissimum) by virus-induced gene silencing.

    PubMed

    Chantreau, Maxime; Chabbert, Brigitte; Billiard, Sylvain; Hawkins, Simon; Neutelings, Godfrey

    2015-12-01

    Flax (Linum usitatissimum) bast fibres are located in the stem cortex where they play an important role in mechanical support. They contain high amounts of cellulose and so are used for linen textiles and in the composite industry. In this study, we screened the annotated flax genome and identified 14 distinct cellulose synthase (CESA) genes using orthologous sequences previously identified. Transcriptomics of 'primary cell wall' and 'secondary cell wall' flax CESA genes showed that some were preferentially expressed in different organs and stem tissues providing clues as to their biological role(s) in planta. The development for the first time in flax of a virus-induced gene silencing (VIGS) approach was used to functionally evaluate the biological role of different CESA genes in stem tissues. Quantification of transcript accumulation showed that in many cases, silencing not only affected targeted CESA clades, but also had an impact on other CESA genes. Whatever the targeted clade, inactivation by VIGS affected plant growth. In contrast, only clade 1- and clade 6-targeted plants showed modifications in outer-stem tissue organization and secondary cell wall formation. In these plants, bast fibre number and structure were severely impacted, suggesting that the targeted genes may play an important role in the establishment of the fibre cell wall. Our results provide new fundamental information about cellulose biosynthesis in flax that should facilitate future plant improvement/engineering. PMID:25688574

  8. A novel virus-inducible enhancer of the interferon-β gene with tightly linked promoter and enhancer activities

    PubMed Central

    Banerjee, A. Raja; Kim, Yoon Jung; Kim, Tae Hoon

    2014-01-01

    Long-range enhancers of transcription are a key component of the genomic regulatory architecture. Recent studies have identified bi-directionally transcribed RNAs emanating from these enhancers known as eRNAs. However, it remains unclear how tightly coupled eRNA production is with enhancer activity. Through our systematic search for long-range elements that interact with the interferon-β gene, a model system for studying inducible transcription, we have identified a novel enhancer, which we have named L2 that regulates the expression of interferon-β. We have demonstrated its virus-inducible enhancer activity by analyzing epigenomic profiles, transcription factor association, nascent RNA production and activity in reporter assays. This enhancer exhibits intimately linked virus-inducible enhancer and bidirectional promoter activity that is largely dependent on a conserved Interferon Stimulated Response Element and robustly generates virus inducible eRNAs. Notably, its enhancer and promoter activities are fully retained in reporter assays even upon a complete elimination of its associated eRNA sequences. Finally, we show that L2 regulates IFNB1 expression by siRNA knockdown of eRNAs, and the deletion of L2 in a BAC transfection assay. Thus, L2 is a novel enhancer that regulates IFNB1 and whose eRNAs exert significant activity in vivo that is distinct from those activities recapitulated in the luciferase reporter assays. PMID:25348400

  9. Toll-Like Receptor 2 Mediates Fatal Immunopathology in Mice During Treatment of Secondary Pneumococcal Pneumonia Following Influenza

    PubMed Central

    Karlström, Åsa; Heston, Sarah M.; Boyd, Kelli L.; Tuomanen, Elaine I.

    2011-01-01

    Host inflammatory responses contribute to the significant immunopathology that occurs during treatment of secondary bacterial pneumonia following influenza. We undertook the present study to determine the mechanisms underlying disparate outcomes in a mouse model with β-lactam and macrolide antibiotics. Lysis of superinfecting bacteria by ampicillin caused an extensive influx of neutrophils into the lungs resulting in a consolidative pneumonia, necrotic lung damage, and significant mortality. This was mediated through Toll-like receptor (TLR) 2 and was independent of TLR4 and the Streptococcus pneumoniae cytotoxin pneumolysin. Treatment with azithromycin prevented neutrophil accumulation and rescued mice from subsequent mortality. This effect was independent of the antibacterial activity of this macrolide since dual therapy with ampicillin and azithromycin against an azithromycin-resistant strain also was able to cure secondary pneumonia. These data suggest that strategies for eliminating bacteria without lysis coupled with immunomodulation of inflammation should be pursued clinically. PMID:21900488

  10. Immune cells and type 1 IFN in urine of SLE patients correlate with immunopathology in the kidney.

    PubMed

    Scott, Eric; Dooley, Mary Anne; Vilen, Barbara J; Clarke, Stephen H

    2016-07-01

    The immunopathological events in the kidneys of lupus nephritis (LN) patients are poorly understood due in part to the difficulty in acquiring serial biopsies and the inherent limitations in their analysis. To identify a means to circumvent these limitations, we investigated whether immune cells of kidney origin are present in patient urine and whether they correlate with kidney pathology. Flow cytometry analysis was performed on peripheral blood and urine cells of 69 SLE patients, of whom 41 were LN patients. In addition, type I IFN (IFNα/β) levels were determined in plasma and urine by bioassay. Approximately 60% of non-LN patients had urine lymphocytes. In these patients, T cells were always present and predominantly CD8(+), while B cells were either absent or a mixture of naïve and memory B cells. In contrast, >90% of LN patients had urine lymphocytes. In half, the B and T cells resembled those in non-LN patient urine; however, in the remaining patients, the B cells were exclusively Ig-secreting plasmablasts or plasma cells (PB/PCs) and the T cells were predominantly CD4(+). In addition, pDCs and IFNα/β frequently accompanied PB/PCs. The majority of patients with urine PB/PCs presented with proliferative nephritis and a significant loss of kidney function, which in some cases had progressed to end stage renal disease (ESRD). In conclusion, urine can provide access to cells of kidney resident populations for phenotypic and functional characterization. Analysis of these cells provides insight into the kidney immunopathology and may serve as biomarkers to identify patients at risk for developing LN and progressing to ESRD. PMID:27102764

  11. An efficient virus-induced gene silencing vector for maize functional genomics research.

    PubMed

    Wang, Rong; Yang, Xinxin; Wang, Nian; Liu, Xuedong; Nelson, Richard S; Li, Weimin; Fan, Zaifeng; Zhou, Tao

    2016-04-01

    Maize is a major crop whose rich genetic diversity provides an advanced resource for genetic research. However, a tool for rapid transient gene function analysis in maize that may be utilized in most maize cultivars has been lacking, resulting in reliance on time-consuming stable transformation and mutation studies to obtain answers. We developed an efficient virus-induced gene silencing (VIGS) vector for maize based on a naturally maize-infecting cucumber mosaic virus (CMV) strain, ZMBJ-CMV. An infectious clone of ZMBJ-CMV was constructed, and a vascular puncture inoculation method utilizing Agrobacterium was optimized to improve its utility for CMV infection of maize. ZMBJ-CMV was then modified to function as a VIGS vector. The ZMBJ-CMV vector induced mild to moderate symptoms in many maize lines, making it useful for gene function studies in critically important maize cultivars, such as the sequenced reference inbred line B73. Using this CMV VIGS system, expression of two endogenous genes, ZmPDS and ZmIspH, was found to be decreased by 75% and 78%, respectively, compared with non-silenced tissue. Inserts with lengths of 100-300 bp produced the most complete transcriptional and visual silencing phenotypes. Moreover, genes related to autophagy, ZmATG3 and ZmATG8a, were also silenced, and it was found that they function in leaf starch degradation. These results indicate that our ZMBJ-CMV VIGS vector provides a tool for rapid and efficient gene function studies in maize. PMID:26921244

  12. Chalcone synthase as a reporter in virus-induced gene silencing studies of flower senescence.

    PubMed

    Chen, Jen-Chih; Jiang, Cai-Zhong; Gookin, Timothy E; Hunter, Donald A; Clark, David G; Reid, Michael S

    2004-07-01

    Agrobacterium-mediated infection of petunia (Petunia hybrida) plants with tobacco rattle virus (TRV) bearing fragments of Petunia genes resulted in systemic infection and virus-induced gene silencing (VIGS) of the homologous host genes. Infection with TRV containing a phytoene desaturase (PDS) fragment resulted in reduced abundance of PDS transcripts and typical photobleaching of photosynthetic tissues. Infection with TRV containing a chalcone synthase (CHS) fragment resulted in silencing of anthocyanin production in infected flowers. The silencing phenotype ranged from scattered white spots on the normal purple background to entirely white flowers. Symptoms in the V26 cultivar were a diffuse mosaic, but infection of some purple-flowered commercial cultivars resulted in large white sectors and even entirely white flowers. Abundance of CHS transcripts in the white flowers was less than 4% of that in purple flowers on the same plant. Infection with TRV containing a tandem construct of PDS and CHS resulted in leaf photobleaching and white patterns on the flowers. Transcripts of CHS and PDS were reduced both in leaves and in flowers confirming simultaneous silencing of both genes by the tandem construct. We tested the effects of infection with TRV containing CHS and a fragment of a petunia gene encoding for 1-aminocyclopropane-1-carboxylate oxidase (ACO4) Abundance of transcripts encoding ACO4 and ACO1 were reduced (by 5% and 20%, respectively) in infected flowers. Whether the flowers were treated with ACC or pollinated, the white (silenced) flowers or flower sectors produced less ethylene and senesced later than purple (non-silenced) tissues. These results indicate the value of VIGS with tandem constructs containing CHS as reporter and a target gene as a tool for examining the function of floral-associated genes. PMID:15604697

  13. Heterologous virus-induced gene silencing as a promising approach in plant functional genomics.

    PubMed

    Hosseini Tafreshi, Seied Ali; Shariati, Mansour; Mofid, Mohammad Reza; Khayam Nekui, Mojtaba; Esmaeili, Abolghasem

    2012-03-01

    VIGS (virus induced gene silencing) is considered as a powerful genomics tool for characterizing the function of genes in a few closely related plant species. The investigations have been carried out mainly in order to test if a pre-existing VIGS vector can serve as an efficient tool for gene silencing in a diverse array of plant species. Another route of investigation has been the constructing of new viral vectors to act in their hosts. Our approach was the creation of a heterologous system in which silencing of endogenous genes was achieved by sequences isolated from evolutionary remote species. In this study, we showed that a TRV-based vector cloned with sequences from a gymnosperm, Taxus baccata L. silenced the endogenous phytoene desaturase in an angiosperm, N. benthamiana. Our results showed that inserts of between 390 and 724 bp isolated from a conserved fragment of the Taxus PDS led to silencing of its homolog in tobacco. The real time analysis indicated that the expression of PDS was reduced 2.1- to 4.0-fold in pTRV-TbPDS infected plants compared with buffer treated plants. Once the best insert is identified and the conditions are optimized for heterologous silencing by pTRV-TbPDS in tobacco, then we can test if TRV can serve as an efficient silencing vector in Taxus. This strategy could also be used to silence a diverse array of genes from a wide range of species which have no VIGS protocol. The results also showed that plants silenced heterologously by the VIGS system a minimally affected with respect to plant growth which may be ideal for studying the genes that their complete loss of function may lead to decrease of plant growth or plant death. PMID:21655951

  14. Tiotropium Attenuates Virus-Induced Pulmonary Inflammation in Cigarette Smoke-Exposed Mice.

    PubMed

    Bucher, Hannes; Duechs, Matthias J; Tilp, Cornelia; Jung, Birgit; Erb, Klaus J

    2016-06-01

    Viral infections trigger exacerbations in chronic obstructive pulmonary disease (COPD), and tiotropium, a M3 receptor antagonist, reduces exacerbations in patients by unknown mechanisms. In this report, we investigated whether tiotropium has anti-inflammatory effects in mice exposed to cigarette smoke (CS) and infected with influenza virus A/PR/8/34 (H1N1) or respiratory syncytial virus (RSV) and compared these effects with those of steroid fluticasone and PDE4-inhibitor roflumilast. Mice were exposed to CS; infected with H1N1 or RSV; and treated with tiotropium, fluticasone, or roflumilast. The amount of cells and cytokine levels in the airways, lung function, and viral load was determined. NCI-H292 cells were infected with H1N1 or RSV and treated with the drugs. In CS/H1N1-exposed mice, tiotropium reduced neutrophil and macrophage numbers and levels of interleukin-6 (IL-6) and interferon-γ (IFN-γ) in the airways and improved lung function. In contrast, fluticasone increased the loss of body weight; failed to reduce neutrophil or macrophage numbers; increased IL-6, KC, and tumor necrosis factor-α (TNF-α) in the lungs; and worsened lung function. Treatment with roflumilast reduced macrophage numbers, IL-6, and KC in the lungs but had no effect on neutrophil numbers or lung function. In CS/RSV-exposed mice, treatment with tiotropium, but not fluticasone or roflumilast, reduced neutrophil numbers and IL-6 and TNF-α levels in the lungs. Viral load of H1N1 and RSV was significantly elevated in CS/virus-exposed mice and NCI-H292 cells after fluticasone treatment, whereas tiotropium and roflumilast had no effect. In conclusion, tiotropium has anti-inflammatory effects on CS/virus-induced inflammation in mice that are superior to the effects of roflumilast and fluticasone. This finding might help to explain the observed reduction of exacerbation rates in COPD patients. PMID:27016458

  15. Contrasting community versus population-based estimates of grazing and virus-induced mortality of phytoplankton.

    PubMed

    Staniewski, Michael A; Short, Cindy M; Short, Steven M

    2012-07-01

    In this study, grazing and virus-induced mortality of phytoplankton was investigated in a freshwater pond at the University of Toronto Mississauga, Canada, during September 2009. The modified dilution assay, which partitions phytoplankton mortality into virus and grazing-induced fractions, was used along with newly designed, taxon-specific quantitative polymerase chain reaction (qPCR) assays that target psbA gene fragments to estimate growth and mortality rates for both the entire phytoplankton community and four distinct phytoplankton populations. Community mortality was estimated via fluorometric determination of chlorophyll a (Chl a) concentrations, whereas the relative mortality of individual phytoplankton populations was estimated via qPCR. The sources and amounts of mortality for individual phytoplankton populations differed from those of the whole community, as well as from each other. Grazing was found to be the only significant source of mortality for the community (0.32 day(-1)), and the Prymnesiales (1.65 day(-1)) and Chroococcales (2.79 day(-1)) populations studied. On the other hand, the Chlamydomonadales population examined experienced both significant grazing (1.01 day(-1)) and viral lysis (0.96 day(-1)), while the Chlorellales population only experienced significant mortality as a result of viral lysis (1.38 day(-1)). Our results demonstrate that the combination of qPCR and the modified dilution method can be used to estimate both viral lysis and grazing pressure on several individual phytoplankton populations within a community simultaneously. Further, previously noted limitations of the modified dilution method associated with the dilution of specific phytoplankton populations at low abundances can be overcome with the qPCR-based approach. Most importantly, this study demonstrates that when used alone, whole community-based methods of assessing mortality can overlook valuable information about carbon flow in aquatic microbial food webs. PMID

  16. Ligand Modulation of the Epstein-Barr Virus-induced Seven-transmembrane Receptor EBI2

    PubMed Central

    Benned-Jensen, Tau; Smethurst, Christopher; Holst, Peter J.; Page, Kevin R.; Sauls, Howard; Sivertsen, Bjørn; Schwartz, Thue W.; Blanchard, Andy; Jepras, Robert; Rosenkilde, Mette M.

    2011-01-01

    The Epstein-Barr virus-induced receptor 2 (EBI2) is a constitutively active seven-transmembrane receptor, which was recently shown to orchestrate the positioning of B cells in the follicle. To date, no ligands, endogenously or synthetic, have been identified that modulate EBI2 activity. Here we describe an inverse agonist, GSK682753A, which selectively inhibited the constitutive activity of EBI2 with high potency and efficacy. In cAMP-response element-binding protein-based reporter and guanosine 5′-3-O-(thio)triphosphate (GTPγS) binding assays, the potency of this compound was 2.6–53.6 nm, and its inhibitory efficacy was 75%. In addition, we show that EBI2 constitutively activated extracellular signal-regulated kinase (ERK) in a pertussis toxin-insensitive manner. Intriguingly, GSK682753A inhibited ERK phosphorylation, GTPγS binding, and cAMP-response element-binding protein activation with similar potency. Overexpression of EBI2 profoundly potentiated antibody-stimulated ex vivo proliferation of murine B cells compared with WT cells, whereas this was equivalently reduced for EBI2-deficient B cells. Inhibition of EBI2 constitutive activity suppressed the proliferation in all cases. Importantly, the suppression was of much higher potency (32-fold) in WT or EBI2-overexpressing B cells compared with EBI2-deficient counterparts. Finally, we screened GSK682753A against an EBI2 mutant library to determine putative molecular binding determinants in EBI2. We identified Phe111 at position III:08/3.32 as being crucial for GSK682753A inverse agonism because Ala substitution resulted in a >500-fold decrease in IC50. In conclusion, we present the first ligand targeting EBI2. In turn, this molecule provides a useful tool for further characterization of EBI2 as well as serving as a potent lead compound. PMID:21673108

  17. Latitudinal variation in virus-induced mortality of phytoplankton across the North Atlantic Ocean.

    PubMed

    Mojica, Kristina D A; Huisman, Jef; Wilhelm, Steven W; Brussaard, Corina P D

    2016-02-01

    Viral lysis of phytoplankton constrains marine primary production, food web dynamics and biogeochemical cycles in the ocean. Yet, little is known about the biogeographical distribution of viral lysis rates across the global ocean. To address this, we investigated phytoplankton group-specific viral lysis rates along a latitudinal gradient within the North Atlantic Ocean. The data show large-scale distribution patterns of different virus groups across the North Atlantic that are associated with the biogeographical distributions of their potential microbial hosts. Average virus-mediated lysis rates of the picocyanobacteria Prochlorococcus and Synechococcus were lower than those of the picoeukaryotic and nanoeukaryotic phytoplankton (that is, 0.14 per day compared with 0.19 and 0.23 per day, respectively). Total phytoplankton mortality (virus plus grazer-mediated) was comparable to the gross growth rate, demonstrating high turnover rates of phytoplankton populations. Virus-induced mortality was an important loss process at low and mid latitudes, whereas phytoplankton mortality was dominated by microzooplankton grazing at higher latitudes (>56°N). This shift from a viral-lysis-dominated to a grazing-dominated phytoplankton community was associated with a decrease in temperature and salinity, and the decrease in viral lysis rates was also associated with increased vertical mixing at higher latitudes. Ocean-climate models predict that surface warming will lead to an expansion of the stratified and oligotrophic regions of the world's oceans. Our findings suggest that these future shifts in the regional climate of the ocean surface layer are likely to increase the contribution of viral lysis to phytoplankton mortality in the higher-latitude waters of the North Atlantic, which may potentially reduce transfer of matter and energy up the food chain and thus affect the capacity of the northern North Atlantic to act as a long-term sink for CO2. PMID:26262815

  18. Tiotropium Attenuates Virus-Induced Pulmonary Inflammation in Cigarette Smoke–Exposed Mice

    PubMed Central

    Bucher, Hannes; Duechs, Matthias J.; Tilp, Cornelia; Jung, Birgit

    2016-01-01

    Viral infections trigger exacerbations in chronic obstructive pulmonary disease (COPD), and tiotropium, a M3 receptor antagonist, reduces exacerbations in patients by unknown mechanisms. In this report, we investigated whether tiotropium has anti-inflammatory effects in mice exposed to cigarette smoke (CS) and infected with influenza virus A/PR/8/34 (H1N1) or respiratory syncytial virus (RSV) and compared these effects with those of steroid fluticasone and PDE4-inhibitor roflumilast. Mice were exposed to CS; infected with H1N1 or RSV; and treated with tiotropium, fluticasone, or roflumilast. The amount of cells and cytokine levels in the airways, lung function, and viral load was determined. NCI-H292 cells were infected with H1N1 or RSV and treated with the drugs. In CS/H1N1-exposed mice, tiotropium reduced neutrophil and macrophage numbers and levels of interleukin-6 (IL-6) and interferon-γ (IFN-γ) in the airways and improved lung function. In contrast, fluticasone increased the loss of body weight; failed to reduce neutrophil or macrophage numbers; increased IL-6, KC, and tumor necrosis factor-α (TNF-α) in the lungs; and worsened lung function. Treatment with roflumilast reduced macrophage numbers, IL-6, and KC in the lungs but had no effect on neutrophil numbers or lung function. In CS/RSV-exposed mice, treatment with tiotropium, but not fluticasone or roflumilast, reduced neutrophil numbers and IL-6 and TNF-α levels in the lungs. Viral load of H1N1 and RSV was significantly elevated in CS/virus-exposed mice and NCI-H292 cells after fluticasone treatment, whereas tiotropium and roflumilast had no effect. In conclusion, tiotropium has anti-inflammatory effects on CS/virus-induced inflammation in mice that are superior to the effects of roflumilast and fluticasone. This finding might help to explain the observed reduction of exacerbation rates in COPD patients. PMID:27016458

  19. Multiple proto-oncogene activations in avian leukosis virus-induced lymphomas: evidence for stage-specific events.

    PubMed Central

    Clurman, B E; Hayward, W S

    1989-01-01

    We have examined avian leukosis virus-induced B-cell lymphomas for multiple, stage-specific oncogene activations. Three targets for viral integration were identified: c-myb, c-myc, and a newly identified locus termed c-bic. The c-myb and c-myc genes were associated with different lymphoma phenotypes. The c-bic locus was a target for integration in one class of lymphomas, usually in conjunction with c-myc activation. The data indicate that c-myc and c-bic may act synergistically during lymphomagenesis and that c-bic is involved in late stages of tumor progression. Images PMID:2548084

  20. Histone deacetylase inhibitors suppress RSV infection and alleviate virus-induced airway inflammation.

    PubMed

    Feng, Qiuqin; Su, Zhonglan; Song, Shiyu; Χu, Hui; Zhang, Bin; Yi, Long; Tian, Man; Wang, Hongwei

    2016-09-01

    Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in infants and young children. However, the majority of RSV-infected patients only show mild symptoms. Different severities of infection and responses among the RSV-infected population indicate that epigenetic regulation as well as personal genetic background may affect RSV infectivity. Histone deacetylase (HDAC) is an important epigenetic regulator in lung diseases. The present study aimed to explore the possible connection between HDAC expression and RSV-induced lung inflammation. To address this question, RSV-infected airway epithelial cells (BEAS‑2B) were prepared and a mouse model of RSV infection was established, and then treated with various concentrations of HDAC inhibitors (HDACis), namely trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA). Viral replication and markers of virus-induced airway inflammation or oxidative stress were assessed. The activation of the nuclear factor-κB (NF-κB), cyclo-oxygenase-2 (COX-2), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) signaling pathways was evaluated by western blot analysis. Our results showed that RSV infection in airway epithelial cells (AECs) significantly decreased histone acetylation levels by altering HDAC2 expression. The treatment of RSV-infected AECs with HDACis significantly restricted RSV replication by upregulating the interferon-α (IFN-α) related signaling pathways. The treatment of RSV-infected AECs with HDACis also significantly inhibited RSV-induced pro-inflammatory cytokine release [interleukin (IL)-6 and IL-8] and oxidative stress-related molecule production [malondialdehyde (MDA), and nitrogen monoxide (NO)]. The activation of NF-κB, COX-2, MAPK and Stat3, which orchestrate pro‑inflammatory gene expression and oxidative stress injury, was also significantly inhibited. Our in vivo study using a mouse model of

  1. Histone deacetylase inhibitors suppress RSV infection and alleviate virus-induced airway inflammation

    PubMed Central

    Feng, Qiuqin; Su, Zhonglan; Song, Shiyu; Xu, Hui; Zhang, Bin; Yi, Long; Tian, Man; Wang, Hongwei

    2016-01-01

    Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in infants and young children. However, the majority of RSV-infected patients only show mild symptoms. Different severities of infection and responses among the RSV-infected population indicate that epigenetic regulation as well as personal genetic background may affect RSV infectivity. Histone deacetylase (HDAC) is an important epigenetic regulator in lung diseases. The present study aimed to explore the possible connection between HDAC expression and RSV-induced lung inflammation. To address this question, RSV-infected airway epithelial cells (BEAS-2B) were prepared and a mouse model of RSV infection was established, and then treated with various concentrations of HDAC inhibitors (HDACis), namely trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA). Viral replication and markers of virus-induced airway inflammation or oxidative stress were assessed. The activation of the nuclear factor-κB (NF-κB), cyclo-oxygenase-2 (COX-2), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) signaling pathways was evaluated by western blot analysis. Our results showed that RSV infection in airway epithelial cells (AECs) significantly decreased histone acetylation levels by altering HDAC2 expression. The treatment of RSV-infected AECs with HDACis significantly restricted RSV replication by upregulating the interferon-α (IFN-α) related signaling pathways. The treatment of RSV-infected AECs with HDACis also significantly inhibited RSV-induced pro-inflammatory cytokine release [interleukin (IL)-6 and IL-8] and oxidative stress-related molecule production [malondialdehyde (MDA), and nitrogen monoxide (NO)]. The activation of NF-κB, COX-2, MAPK and Stat3, which orchestrate pro-inflammatory gene expression and oxidative stress injury, was also significantly inhibited. Our in vivo study using a mouse model of RSV infection

  2. Detection of a unique antigen on radiation leukemia virus-induced leukemia B6RV2

    SciTech Connect

    Nakayama, E.; Uenaka, A.; Stockert, E.; Obata, Y.

    1984-11-01

    Radiation leukemia virus-induced leukemia of a male C57BL/6 mouse, B6RV2, is immunogenic to female BALB/c X C57BL/6 F1 mice. In these mice, B6RV2 tumors regressed after initial growth, and after tumor regression the mice were resistant to repeated inocula of up to 10(8) B6RV2 cells. Serum from these mice reacted with B6RV2 in mixed hemadsorption or protein A assays, and absorption analysis indicated that the antigen was restricted to B6RV2; it could not be detected in normal thymocytes or spleen concanavalin A blasts from different inbred strains, nor in 16 C57BL/6 or BALB/c leukemias. Spleen cells from mice in which the tumor had regressed were cytotoxic to B6RV2 after in vitro stimulation with B6RV2, as shown by /sup 51/chromium release assay. This cytotoxicity was eliminated by pretreatment of the cells with anti-Thy-1.2, anti-Lyt-2.2, anti-Lyt-3.2, and complement, indicating that the effector cells were T-cells. The specificity of T-cell killing of B6RV2 was examined by competitive inhibition assays with unlabeled cells; only B6RV2 inhibited killing, while eight other C57BL/6 leukemias did not inhibit. Thus, the antigen on B6RV2 defined serologically and by cytotoxic T-cells is a unique antigen. However, it was not revealed by antibody-blocking test whether the unique determinant defined serologically was related to that recognized by T-cells; B6RV2 antiserum did not block lytic activity in the absence of added complement, irrespective of whether the target cells were untreated or anti-H-2b-treated B6RV2. H-2Kb antisera, but not H-2Db antisera, blocked lysis. This indicated that the H-2Kb molecule was exclusively involved in recognition of B6RV2 by cytotoxic T-cell.

  3. Dietary Vitamin D3 Suppresses Pulmonary Immunopathology Associated with Late-Stage Tuberculosis in C3HeB/FeJ Mice.

    PubMed

    Reeme, Allison E; Robinson, Richard T

    2016-02-01

    Tuberculosis (TB) is a significant human disease caused by inhalation of Mycobacterium tuberculosis. Left untreated, TB mortality is associated with a failure to resolve pulmonary immunopathology. There is currently widespread interest in using vitamin D3 (VitD3) as an adjunct therapy for TB because numerous in vitro studies have shown that VitD3 has direct and indirect mycobactericidal activities. However, to date, there have been no in vivo studies addressing whether VitD3 affects experimental TB outcome. In this study, we used C3HeB/FeJ mice to determine whether dietary VitD3 influences the outcome of experimental TB. We observed that although M. tuberculosis burdens did not differ between mice on a VitD3-replete diet (VitD(HI) mice) and mice on a VitD3-deficient diet (VitD(LO) mice), the inflammatory response in VitD(HI) mice was significantly attenuated relative to VitD(LO) controls. Specifically, the expression of multiple inflammatory pathways was reduced in the lungs at later disease stages as were splenocyte IL12/23p40 and IFN-γ levels following ex vivo restimulation. Dietary VitD3 also suppressed the accumulation of T cells in the mediastinal lymph nodes and lung granulomatous regions while concomitantly accelerating the accumulation of F4/80(+) and Ly6C/Ly6G(+) lineages. The altered inflammatory profile of VitD(HI) mice also associated with reductions in pulmonary immunopathology. VitD receptor-deficient (vdr(-/-)) radiation bone marrow chimeras demonstrate that reductions in pulmonary TB immunopathology are dependent on hematopoietic VitD responsiveness. Collectively, our data support a model wherein the in vivo role of VitD3 during TB is not to promote M. tuberculosis killing but rather to function through hematopoietic cells to reduce M. tuberculosis-elicited immunopathology. PMID:26729807

  4. Functional Interplay between Type I and II Interferons Is Essential to Limit Influenza A Virus-Induced Tissue Inflammation

    PubMed Central

    Stifter, Sebastian A.; Bhattacharyya, Nayan; Pillay, Roman; Flórido, Manuela; Triccas, James A.; Britton, Warwick J.; Feng, Carl G.

    2016-01-01

    Host control of influenza A virus (IAV) is associated with exuberant pulmonary inflammation characterized by the influx of myeloid cells and production of proinflammatory cytokines including interferons (IFNs). It is unclear, however, how the immune system clears the virus without causing lethal immunopathology. Here, we demonstrate that in addition to its known anti-viral activity, STAT1 signaling coordinates host inflammation during IAV infection in mice. This regulatory mechanism is dependent on both type I IFN and IFN-γ receptor signaling and, importantly, requires the functional interplay between the two pathways. The protective function of type I IFNs is associated with not only the recruitment of classical inflammatory Ly6Chi monocytes into IAV-infected lungs, but also the prevention of excessive monocyte activation by IFN-γ. Unexpectedly, type I IFNs preferentially regulate IFN-γ signaling in Ly6Clo rather than inflammatory Ly6Chi mononuclear cell populations. In the absence of type I IFN signaling, Ly6Clo monocytes/macrophages, become phenotypically and functionally more proinflammatory than Ly6Chi cells, revealing an unanticipated function of the Ly6Clo mononuclear cell subset in tissue inflammation. In addition, we show that type I IFNs employ distinct mechanisms to regulate monocyte and neutrophil trafficking. Type I IFN signaling is necessary, but not sufficient, for preventing neutrophil recruitment into the lungs of IAV-infected mice. Instead, the cooperation of type I IFNs and lymphocyte-produced IFN-γ is required to regulate the tissue neutrophilic response to IAV. Our study demonstrates that IFN interplay links innate and adaptive anti-viral immunity to orchestrate tissue inflammation and reveals an additional level of complexity for IFN-dependent regulatory mechanisms that function to prevent excessive immunopathology while preserving anti-microbial functions. PMID:26731100

  5. A conserved virus-induced cytoplasmic TRAMP-like complex recruits the exosome to target viral RNA for degradation.

    PubMed

    Molleston, Jerome M; Sabin, Leah R; Moy, Ryan H; Menghani, Sanjay V; Rausch, Keiko; Gordesky-Gold, Beth; Hopkins, Kaycie C; Zhou, Rui; Jensen, Torben Heick; Wilusz, Jeremy E; Cherry, Sara

    2016-07-15

    RNA degradation is tightly regulated to selectively target aberrant RNAs, including viral RNA, but this regulation is incompletely understood. Through RNAi screening in Drosophila cells, we identified the 3'-to-5' RNA exosome and two components of the exosome cofactor TRAMP (Trf4/5-Air1/2-Mtr4 polyadenylation) complex, dMtr4 and dZcchc7, as antiviral against a panel of RNA viruses. We extended our studies to human orthologs and found that the exosome as well as TRAMP components hMTR4 and hZCCHC7 are antiviral. While hMTR4 and hZCCHC7 are normally nuclear, infection by cytoplasmic RNA viruses induces their export, forming a cytoplasmic complex that specifically recognizes and induces degradation of viral mRNAs. Furthermore, the 3' untranslated region (UTR) of bunyaviral mRNA is sufficient to confer virus-induced exosomal degradation. Altogether, our results reveal that signals from viral infection repurpose TRAMP components to a cytoplasmic surveillance role where they selectively engage viral RNAs for degradation to restrict a broad range of viruses. PMID:27474443

  6. The significance of T cells, B cells, antibodies and macrophages against encephalomyocarditis (EMC)-D virus-induced diabetes in mice.

    PubMed

    Kounoue, Etsushi; Izumi, Ken-ichi; Ogawa, Shuichiro; Kondo, Shiori; Katsuta, Hitoshi; Akashi, Tomoyuki; Niho, Yoshiyuki; Harada, Mine; Tamiya, Sadafumi; Kurisaki, Hironori; Nagafuchi, Seiho

    2008-01-01

    In order to clarify the significance of protective mechanisms against encephalomyocarditis (EMC) virus-induced diabetes in mice, we studied the relative importance of T cells, B cells, antibodies and macrophages in the prevention of virus-induced diabetes. Neither T cell-deficient athymic nude mice nor B cell-deficient microMT/microMT mice showed an enhanced clinical course of EMC-D virus-induced diabetes, indicating that neither T cells nor B cells played a major role in the protection against EMC-D-virus-induced diabetes. Transfer of a large amount of antiserum to EMC-D-virus-infected mice protected the development of diabetes only when transferred within 36 h of infection, the timing of which was earlier than that for the production of natural neutralizing antibodied. Since pretreatment of mice with the macrophage-activating immunopotentiator Corynebacterium parvum (CP) completely prevented the development of diabetes, we studied the clinical outcome of EMC-D-virus-infected mice pretreated with CP. Mice treated with CP showed reduced proliferation of EMC-D virus in the affected organs, including the pancreas, while the levels of development of neutralizing antibody and serum interferon were not enhanced compared with the controls. Finally, we studied the macrophages derived from mice pretreated with CP and found that they inhibited the growth of EMC-D virus in vitro more than those derived from non-treated and thioglycolate-treated mice. Taken together, it can be suggested that neither T cells nor B cells, which have to do with adaptive immunity, play a significant role in the pathogenesis of EMC-D-virus-induced diabetes, while innate immunity, which is dependent on activated macrophages, contributes to in vivo resistance against EMC-D-virus-induced diabetes. PMID:18500429

  7. Comparison of rapid immunodiagnosis assay kit with molecular and immunopathological approaches for diagnosis of rabies in cattle

    PubMed Central

    Ahmad, Ajaz; Singh, C. K.

    2016-01-01

    Aim: Presently, diagnosis of rabies is primarily based on, conventional fluorescent antibody technique (FAT), immunopathological and molecular techniques. Recently, rapid immunodiagnostic assay (RIDA) - A monoclonal antibody-based technique has been introduced for rapid diagnosis of rabies. The present investigation is envisaged to study the efficacy of RIDA kit for the diagnosis of rabies in cattle. Materials and Methods: About 11 brain samples from cattle, clinically suspected for rabies, were screened by the FAT, Heminested reverse transcriptase polymerase chain reaction (HnRT-PCR), Immunohistochemistry (IHC), and RIDA. Results: The sensitivity for detection of rabies from brain tissue by RIDA was 85.7% as compared to 100% by IHC as well as HnRT-PCR. The accuracy of detection of rabies by RIDA was 91.6% as compared to 100% that of IHC and HnRT-PCR, whereas specificity of RIDA was 100% like that of the IHC and HnRT-PCR. Conclusion: Despite a comparatively low-sensitivity and accuracy of RIDA, latter can still be useful in screening a large number of field samples promptly. However, it is recommended that negative results with RIDA in cattle need to be authenticated by suitable alternative diagnostic approaches. PMID:27051193

  8. Chronic graft-versus-host disease in the rat radiation chimera. III. Immunology and immunopathology in rapidly induced models

    SciTech Connect

    Beschorner, W.E.; Tutschka, P.J.; Santos, G.W.

    1983-03-01

    Although chronic graft-versus-host disease (GVHD) frequently develops in the long-term rat radiation chimera, we present three additional models in which a histologically similar disease is rapidly induced. These include adoptive transfer of spleen and bone marrow from rats with spontaneous chronic GVHD into lethally irradiated rats of the primary host strain; sublethal irradiation of stable chimeras followed by a booster transplant; and transfer of spleen cells of chimeras recovering from acute GVHD into second-party (primary recipient strain) or third-party hosts. Some immunopathologic and immune abnormalities associated with spontaneous chronic GVHD were not observed in one or more of the induced models. Thus, IgM deposition in the skin, antinuclear antibodies, and vasculitis appear to be paraphenomena. On the other hand, lymphoid hypocellularity of the thymic medulla, immaturity of splenic follicles, and nonspecific suppressor cells were consistently present in the long term chimeras, and in all models. These abnormalities therefore may be pathogenetically important, or closely related to the development of chronic GVHD.

  9. A Numerically Subdominant CD8 T Cell Response to Matrix Protein of Respiratory Syncytial Virus Controls Infection with Limited Immunopathology

    PubMed Central

    Liu, Jie; Haddad, Elias K.; Marceau, Joshua; Morabito, Kaitlyn M.; Rao, Srinivas S.; Filali-Mouhim, Ali; Sekaly, Rafick-Pierre; Graham, Barney S.

    2016-01-01

    CD8 T cells are involved in pathogen clearance and infection-induced pathology in respiratory syncytial virus (RSV) infection. Studying bulk responses masks the contribution of individual CD8 T cell subsets to protective immunity and immunopathology. In particular, the roles of subdominant responses that are potentially beneficial to the host are rarely appreciated when the focus is on magnitude instead of quality of response. Here, by evaluating CD8 T cell responses in CB6F1 hybrid mice, in which multiple epitopes are recognized, we found that a numerically subdominant CD8 T cell response against DbM187 epitope of the virus matrix protein expressed high avidity TCR and enhanced signaling pathways associated with CD8 T cell effector functions. Each DbM187 T effector cell lysed more infected targets on a per cell basis than the numerically dominant KdM282 T cells, and controlled virus replication more efficiently with less pulmonary inflammation and illness than the previously well-characterized KdM282 T cell response. Our data suggest that the clinical outcome of viral infections is determined by the integrated functional properties of a variety of responding CD8 T cells, and that the highest magnitude response may not necessarily be the best in terms of benefit to the host. Understanding how to induce highly efficient and functional T cells would inform strategies for designing vaccines intended to provide T cell-mediated immunity. PMID:26943673

  10. Evaluation of immunopathologic effects of aqueous extract of Echinacea purpurea in mice after experimental challenge with Pasteurella multocida serotype A

    PubMed Central

    Rezaie, A; Gharibi, D; Ghorbanpoor, M; Anbari, S; Pourmahdi Broojeni, M

    2014-01-01

    In order to assess the immunopathological effects of aqueous Echinacea purpurea extract (EPE) on mice experimentally challenged with Pasteurella multocida serotype A, forty female BALB/c mice were randomly divided into four groups. The groups included a control group (received sterile distilled water 2 times/week for 2 weeks, intraperitoneally and then 100 µl sterile saline intranasally), a PMA group (received sterile distilled water as the control group and after 2 weeks, 5.6 × 103 CFU/ml of P. multocida serotype A, intranasally), an EPE+PMA group (received E. purpurea extract intraperitoneally 2 times/week for 2 weeks and then challenged as the PMA group) and an EPE group (received E. purpurea extract as EPE+PMA group and then 100 µl sterile saline intranasally). After 24 and 48 h post challenge, half of the animals in each group were sacrificed and analyzed for bacterial counts in their lungs and livers, TNFα serum levels and histapathological changes. The results showed significant differences in lung bacterial counts between PMA and EPE+PMA groups. TNFα serum level was significantly higher in the PMA group. Histopathological examination revealed infiltration of neutrophils in alveolar septa and hyperemia in the PMA group. In addition, the criteria of bronchopneumonia were partially recovered in the EPE+PMA compared to the PMA group. According to the results, it seems that E. purpurea extract has an immunomodulatory effect and can be used to prevent or control of pneumonia caused by Pasteurella. PMID:27175135

  11. Dimethyl fumarate suppresses Theiler's murine encephalomyelitis virus-induced demyelinating disease by modifying the Nrf2-Keap1 pathway.

    PubMed

    Kobayashi, Kunitoshi; Tomiki, Hiroki; Inaba, Yuji; Ichikawa, Motoki; Kim, Byung S; Koh, Chang-Sung

    2015-07-01

    Dimethyl fumarate (DMF) is a modifier of the nuclear factor (erythroid-derived 2)-2 (Nrf2)-kelch-like ECH-associated protein 1 (Keap1) pathway. DMF treatment in the effector phase significantly suppressed the development of Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD) both clinically and histologically. DMF treatment leads to an enhanced Nrf2 antioxidant response in TMEV-IDD mice. DMF treatment in the effector phase significantly suppressed the level of IL-17A mRNA. DMF is known to inhibit differentiation of T helper 17 (Th17) cells via suppressing NF-κB. Taken together, our data suggest that DMF treatment in the effector phase may suppress TMEV-IDD not only via enhancing the antioxidant response but also via suppressing IL-17A. PMID:25721871

  12. Virus induced gene silencing (VIGS) for functional analysis of wheat genes involved in Zymoseptoria tritici susceptibility and resistance

    PubMed Central

    Lee, Wing-Sham; Rudd, Jason J.; Kanyuka, Kostya

    2015-01-01

    Virus-induced gene silencing (VIGS) has emerged as a powerful reverse genetic technology in plants supplementary to stable transgenic RNAi and, in certain species, as a viable alternative approach for gene functional analysis. The RNA virus Barley stripe mosaic virus (BSMV) was developed as a VIGS vector in the early 2000s and since then it has been used to study the function of wheat genes. Several variants of BSMV vectors are available, with some requiring in vitro transcription of infectious viral RNA, while others rely on in planta production of viral RNA from DNA-based vectors delivered to plant cells either by particle bombardment or Agrobacterium tumefaciens. We adapted the latest generation of binary BSMV VIGS vectors for the identification and study of wheat genes of interest involved in interactions with Zymoseptoria tritici and here present detailed and the most up-to-date protocols. PMID:26092793

  13. Characterization of Clonality of Epstein-Barr Virus-Induced Human B Lymphoproliferative Disease in Mice with Severe Combined Immunodeficiency

    PubMed Central

    Nakamine, Hirokazu; Masih, Aneal S.; Okano, Motohiko; Taguchi, Yuichi; Pirruccello, Samuel J.; Davis, Jack R.; Mahloch, Mark L.; Beisel, Kirk W.; Kleveland, Kimberly; Sanger, Warren G.; Purtilo, David T.

    1993-01-01

    To improve the diagnostic accuracy and understanding of the pathogenesis of lymphoproliferative diseases (LPDs) occurring in immunosuppressed transplant recipients (post-transplantation LPD), clonality of Epstein-Barr virus-induced human LPDs in mice with severe combined immunodeficiency was examined by analyzing: 1) human immunoglobulin genes and their products, 2) the clonality of Epstein-Barr virus DNA, and 3) genetic alteration of c-myc or bcl-2 genes. A spectrum of clonality was found in the LPDs comparable with that reported for post-transplantation LPDs, although rearrangements of c-myc or bcl-2 genes were not detected. It is confirmed that this system is useful in terms of clonality for understanding the early phases in the pathogenesis of post-transplantation LPD or LPD in immune deficient patients. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:8380952

  14. Institutional Animal Care and Use Committee Considerations Regarding the Use of Virus-Induced Carcinogenesis and Oncolytic Viral Models.

    PubMed

    Lewis, Stephanie D; Hickman-Davis, Judy M; Bergdall, Valerie K

    2016-03-31

    The use of virus-induced carcinogenesis and oncologic experimental animal models is essential in understanding the mechanisms of cancer development to advance prevention, diagnosis, and treatment methods. The Institutional Animal Care and Use Committee (IACUC) is responsible for both the complex philosophical and practical considerations associated with animal models of cancer. Animal models of cancer carry their own unique issues that require special consideration from the IACUC. Many of the considerations to be discussed apply to cancer models in general; specific issues related to viral carcinogenesis or oncolytic viruses will be specifically discussed as they arise. Responsible animal use integrates good science, humane care, and regulatory compliance. To meet those standards, the IACUC, in conjunction with the research investigator and attending veterinarian, must address a wide range of issues, including animal model selection, cancer model selection, humane end point considerations, experimental considerations, postapproval monitoring, reporting requirements, and animal management and personnel safety considerations. PMID:27034398

  15. Novel Avian Influenza A (H7N9) Virus Induces Impaired Interferon Responses in Human Dendritic Cells

    PubMed Central

    Arilahti, Veera; Mäkelä, Sanna M.; Tynell, Janne; Julkunen, Ilkka; Österlund, Pamela

    2014-01-01

    In March 2013 a new avian influenza A(H7N9) virus emerged in China and infected humans with a case fatality rate of over 30%. Like the highly pathogenic H5N1 virus, H7N9 virus is causing severe respiratory distress syndrome in most patients. Based on genetic analysis this avian influenza A virus shows to some extent adaptation to mammalian host. In the present study, we analyzed the activation of innate immune responses by this novel H7N9 influenza A virus and compared these responses to those induced by the avian H5N1 and seasonal H3N2 viruses in human monocyte-derived dendritic cells (moDCs). We observed that in H7N9 virus-infected cells, interferon (IFN) responses were weak although the virus replicated as well as the H5N1 and H3N2 viruses in moDCs. H7N9 virus-induced expression of pro-inflammatory cytokines remained at a significantly lower level as compared to H5N1 virus-induced “cytokine storm” seen in human moDCs. However, the H7N9 virus was extremely sensitive to the antiviral effects of IFN-α and IFN-β in pretreated cells. Our data indicates that different highly pathogenic avian viruses may show considerable differences in their ability to induce host antiviral responses in human primary cell models such as moDCs. The unexpected appearance of the novel H7N9 virus clearly emphasizes the importance of the global influenza surveillance system. It is, however, equally important to systematically characterize in normal human cells the replication capacity of the new viruses and their ability to induce and respond to natural antiviral substances such as IFNs. PMID:24804732

  16. Induction and maintenance of DNA methylation in plant promoter sequences by apple latent spherical virus-induced transcriptional gene silencing.

    PubMed

    Kon, Tatsuya; Yoshikawa, Nobuyuki

    2014-01-01

    Apple latent spherical virus (ALSV) is an efficient virus-induced gene silencing vector in functional genomics analyses of a broad range of plant species. Here, an Agrobacterium-mediated inoculation (agroinoculation) system was developed for the ALSV vector, and virus-induced transcriptional gene silencing (VITGS) is described in plants infected with the ALSV vector. The cDNAs of ALSV RNA1 and RNA2 were inserted between the cauliflower mosaic virus 35S promoter and the NOS-T sequences in a binary vector pCAMBIA1300 to produce pCALSR1 and pCALSR2-XSB or pCALSR2-XSB/MN. When these vector constructs were agroinoculated into Nicotiana benthamiana plants with a construct expressing a viral silencing suppressor, the infection efficiency of the vectors was 100%. A recombinant ALSV vector carrying part of the 35S promoter sequence induced transcriptional gene silencing of the green fluorescent protein gene in a line of N. benthamiana plants, resulting in the disappearance of green fluorescence of infected plants. Bisulfite sequencing showed that cytosine residues at CG and CHG sites of the 35S promoter sequence were highly methylated in the silenced generation zero plants infected with the ALSV carrying the promoter sequence as well as in progeny. The ALSV-mediated VITGS state was inherited by progeny for multiple generations. In addition, induction of VITGS of an endogenous gene (chalcone synthase-A) was demonstrated in petunia plants infected with an ALSV vector carrying the native promoter sequence. These results suggest that ALSV-based vectors can be applied to study DNA methylation in plant genomes, and provide a useful tool for plant breeding via epigenetic modification. PMID:25426109

  17. NK Cell Activation in Human Hantavirus Infection Explained by Virus-Induced IL-15/IL15Rα Expression

    PubMed Central

    Braun, Monika; Björkström, Niklas K.; Gupta, Shawon; Sundström, Karin; Ahlm, Clas; Klingström, Jonas; Ljunggren, Hans-Gustaf

    2014-01-01

    Clinical infection with hantaviruses cause two severe acute diseases, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). These diseases are characterized by strong immune activation, increased vascular permeability, and up to 50% case-fatality rates. One prominent feature observed in clinical hantavirus infection is rapid expansion of natural killer (NK) cells in peripheral blood of affected individuals. We here describe an unusually high state of activation of such expanding NK cells in the acute phase of clinical Puumala hantavirus infection. Expanding NK cells expressed markedly increased levels of activating NK cell receptors and cytotoxic effector molecules. In search for possible mechanisms behind this NK cell activation, we observed virus-induced IL-15 and IL-15Rα on infected endothelial and epithelial cells. Hantavirus-infected cells were shown to strongly activate NK cells in a cell-cell contact-dependent way, and this response was blocked with anti-IL-15 antibodies. Surprisingly, the strength of the IL-15-dependent NK cell response was such that it led to killing of uninfected endothelial cells despite expression of normal levels of HLA class I. In contrast, hantavirus-infected cells were resistant to NK cell lysis, due to a combination of virus-induced increase in HLA class I expression levels and hantavirus-mediated inhibition of apoptosis induction. In summary, we here describe a possible mechanism explaining the massive NK cell activation and proliferation observed in HFRS patients caused by Puumala hantavirus infection. The results add further insights into mechanisms behind the immunopathogenesis of hantavirus infections in humans and identify new possible targets for intervention. PMID:25412359

  18. Antigen-pulsed bone marrow derived and pulmonary dendritic cells promote Th2 cell responses and immunopathology in lungs during the pathogenesis of murine mycoplasma pneumonia1

    PubMed Central

    Dobbs, Nicole A.; Zhou, Xia; Pulse, Mark; Hodge, Lisa M.; Schoeb, Trenton R.; Simecka, Jerry W.

    2014-01-01

    Mycoplasmas are a common cause of pneumonia in humans and animals, and attempts to create vaccines have not only failed to generate protective host responses, but exacerbated the disease. Mycoplasma pulmonis causes a chronic inflammatory lung disease resulting from a persistent infection, similar to other mycoplasma respiratory diseases. Using this model, Th1 subsets promote resistance to mycoplasma disease and infection, while Th2 responses contribute to immunopathology. The purpose of these studies was to evaluate the capacity of cytokine differentiated dendritic cells (DC) populations to influence the generation of protective and/or pathologic immune responses during M. pulmonis respiratory disease in BALB/c mice. We hypothesized that intratracheal inoculation of mycoplasma antigen-pulsed bone marrow derived dendritic cells (BMDC) could result in the generation of protective T cell responses during mycoplasma infection. However, intratracheal inoculation (priming) of mice with antigen-pulsed DCs resulted enhanced pathology in the recipient mice when challenged with mycoplasma. Inoculation of immunodeficient SCID mice with antigen-pulsed DCs demonstrated that this effect was dependent on lymphocyte responses. Similar results were observed when mice were primed with antigen-pulsed pulmonary, but not splenic, DCs. Lymphocytes generated in uninfected mice after the transfer of either antigen-pulsed BMDCs or pulmonary DCs were shown to be IL13+ Th2 cells, known to be associated with immunopathology. Thus, resident pulmonary DC most likely promote the development of immunopathology in mycoplasma disease through the generation of mycoplasma-specific Th2 responses. Vaccination strategies that disrupt or bypass this process could potentially result in a more effective vaccination. PMID:24973442

  19. Virus-induced airway hyperresponsiveness in the guinea-pig: possible involvement of histamine and inflammatory cells.

    PubMed Central

    Folkerts, G.; De Clerck, F.; Reijnart, I.; Span, P.; Nijkamp, F. P.

    1993-01-01

    1. Guinea-pig tracheal contractions by histamine and by the cholinoceptor agonist, arecoline, are significantly enhanced (30% and 20%, respectively), 96 h after intra-tracheal inoculation with Parainfluenza-3 (PI-3) virus. 2. The airway hyperresponsiveness in animals inoculated with virus coincides with a significant increase in the number of broncho-alveolar cells (82%), and in the albumin concentration (121%) in lung lavage fluid, relative to values obtained in guinea-pigs challenged with control solution. 3. The chemiluminescence production by isolated broncho-alveolar cells, obtained from virus-infected guinea-pigs 96 h after inoculation stimulated with PI-3 virus in vitro, is significantly reduced by 42% relative to broncho-alveolar cells obtained from animals inoculated with control solution. This diminution was not specific for stimulation by PI-3 virus since the chemiluminescence production was also significantly reduced by 30% in response to zymosan. 4. Pretreatment of the guinea-pigs with the anti-allergic drugs, oxatomide (2.5 mg kg-1) or nedocromil (2.5 mg kg-1), or the specific H1-histamine receptor antagonist, levocabastine (0.25 mg kg-1), administered intra-peritoneally twice a day for five successive days, inhibits the virus-induced airway hyperresponsiveness, suppresses the influx of broncho-alveolar cells and increase in albumin content, and corrects the reduced chemiluminescence production by broncho-alveolar cells in response to zymosan. 5. In contrast, the cyclo-oxygenase inhibitor, suprofen (5.0 mg kg-1), the 5-HT2 receptor antagonist, ketanserin (0.63 mg kg-1), or the Ca2+ overload blocker, flunarizine (2.5 mg kg-1) do not modify the above mentioned processes. 6. The platelet-activating factor receptor antagonist, WEB 2170 (10 mg kg-1), reduces virus-induced airway hyperresponsiveness and influx of broncho-alveolar cells into the lungs but does not attenuate the increase of albumin in the bronchial lavage fluid. 7. Guinea-pigs nebulized with

  20. Mechanisms for virus-induced liver disease: tumor necrosis factor-mediated pathology independent of natural killer and T cells during murine cytomegalovirus infection.

    PubMed Central

    Orange, J S; Salazar-Mather, T P; Opal, S M; Biron, C A

    1997-01-01

    The contribution of endogenous NK cells and cytokines to virus-induced liver pathology was evaluated during murine cytomegalovirus infections of mice. In immunocompetent C57BL/6 mice, the virus induced a self-limited liver disease characterized by hepatitis, with focal inflammation, and large grossly visible subcapsular necrotic foci. The inflammatory foci were most numerous and contained the greatest number of cells 3 days after infection; they colocalized with areas of viral antigen expression. The largest number of necrotic foci was found 2 days after infection. Overall hepatic damage, assessed as increased expression of liver enzymes in serum, accompanied the development of inflammatory and necrotic foci. Experiments with neutralizing antibodies demonstrated that although virus-induced tumor necrosis factor (TNF) can have antiviral effects, it also mediated significant liver pathology. TNF was required for development of hepatic necrotic foci and increased levels of liver enzymes in serum but not for increased numbers of inflammatory foci. The necrotic foci and liver enzyme indications of pathology occurred independently of NK and T cells, because mice rendered NK-cell deficient by treatment with antibodies, T- and B-cell-deficient Rag-/- mice, and NK- and T-cell-deficient E26 mice all manifested both parameters of disease. Development of necrotic foci and maximally increased levels of liver enzymes in serum also were TNF dependent in NK-cell-deficient mice. Moreover, in the immunodeficient E26 mice, virus-induced liver disease was progressive, with eventual death of the host, and neutralization of TNF significantly increased longevity. These results establish conditions separating hepatitis from significant liver damage and demonstrate a cytokine-mediated component to viral pathogenesis. PMID:9371583

  1. Brain Endothelial- and Epithelial-Specific Interferon Receptor Chain 1 Drives Virus-Induced Sickness Behavior and Cognitive Impairment.

    PubMed

    Blank, Thomas; Detje, Claudia N; Spieß, Alena; Hagemeyer, Nora; Brendecke, Stefanie M; Wolfart, Jakob; Staszewski, Ori; Zöller, Tanja; Papageorgiou, Ismini; Schneider, Justus; Paricio-Montesinos, Ricardo; Eisel, Ulrich L M; Manahan-Vaughan, Denise; Jansen, Stephan; Lienenklaus, Stefan; Lu, Bao; Imai, Yumiko; Müller, Marcus; Goelz, Susan E; Baker, Darren P; Schwaninger, Markus; Kann, Oliver; Heikenwalder, Mathias; Kalinke, Ulrich; Prinz, Marco

    2016-04-19

    Sickness behavior and cognitive dysfunction occur frequently by unknown mechanisms in virus-infected individuals with malignancies treated with type I interferons (IFNs) and in patients with autoimmune disorders. We found that during sickness behavior, single-stranded RNA viruses, double-stranded RNA ligands, and IFNs shared pathways involving engagement of melanoma differentiation-associated protein 5 (MDA5), retinoic acid-inducible gene 1 (RIG-I), and mitochondrial antiviral signaling protein (MAVS), and subsequently induced IFN responses specifically in brain endothelia and epithelia of mice. Behavioral alterations were specifically dependent on brain endothelial and epithelial IFN receptor chain 1 (IFNAR). Using gene profiling, we identified that the endothelia-derived chemokine ligand CXCL10 mediated behavioral changes through impairment of synaptic plasticity. These results identified brain endothelial and epithelial cells as natural gatekeepers for virus-induced sickness behavior, demonstrated tissue specific IFNAR engagement, and established the CXCL10-CXCR3 axis as target for the treatment of behavioral changes during virus infection and type I IFN therapy. PMID:27096319

  2. Decreased Diversity of the Oral Microbiota of Patients with Hepatitis B Virus-Induced Chronic Liver Disease: A Pilot Project.

    PubMed

    Ling, Zongxin; Liu, Xia; Cheng, Yiwen; Jiang, Xiawei; Jiang, Haiyin; Wang, Yuezhu; Li, Lanjuan

    2015-01-01

    Increasing evidence suggests that altered gut microbiota is implicated in the pathogenesis of hepatitis B virus-induced chronic liver disease (HBV-CLD). However, the structure and composition of the oral microbiota of patients with HBV-CLD remains unclear. High-throughput pyrosequencing showed that decreased oral bacterial diversity was found in patients with HBV-CLD. The Firmicutes/Bacteroidetes ratio was increased significantly, which indicated that dysbiosis of the oral microbiota participated in the process of HBV-CLD development. However, the changing patterns of the oral microbiota in patients with HBV-induced liver cirrhosis (LC) were almost similar to patients with chronic hepatitis B (CHB). HBV infection resulted in an increase in potential H2S- and CH3SH-producing phylotypes such as Fusobacterium, Filifactor, Eubacterium, Parvimonas and Treponema, which might contribute to the increased oral malodor. These key oral-derived phylotypes might invade into the gut as opportunistic pathogens and contribute to altering the composition of the gut microbiota. This study provided important clues that dysbiosis of the oral microbiota might be involved in the development of HBV-CLD. Greater understanding of the relationships between the dysbiosis of oral microbiota and the development of HBV-CLD might facilitate the development of non-invasive differential diagnostic procedures and targeted treatments of HBV-CLD patients harbouring specific oral phylotypes. PMID:26606973

  3. Virus-induced gene silencing of pea CHLI and CHLD affects tetrapyrrole biosynthesis, chloroplast development and the primary metabolic network.

    PubMed

    Luo, Tao; Luo, Sha; Araújo, Wagner L; Schlicke, Hagen; Rothbart, Maxi; Yu, Jing; Fan, Tingting; Fernie, Alisdair R; Grimm, Bernhard; Luo, Meizhong

    2013-04-01

    The first committed and highly regulated step of chlorophyll biosynthesis is the insertion of Mg(2+) into protoporphyrin IX, which is catalyzed by Mg chelatase that consists of CHLH, CHLD and CHLI subunits. In this study, CHLI and CHLD genes were suppressed by virus-induced gene silencing (VIGS-CHLI and VIGS-CHLD) in pea (Pisum sativum), respectively. VIGS-CHLI and VIGS-CHLD plants both showed yellow leaf phenotypes with the reduced Mg chelatase activity and the inactivated synthesis of 5-aminolevulinic acid. The lower chlorophyll accumulation correlated with undeveloped thylakoid membranes, altered chloroplast nucleoid structure, malformed antenna complexes and compromised photosynthesis capacity in the yellow leaf tissues of the VIGS-CHLI and VIGS-CHLD plants. Non-enzymatic antioxidant contents and the activities of antioxidant enzymes were altered in response to enhanced accumulation of reactive oxygen species (ROS) in the chlorophyll deficient leaves of VIGS-CHLI and VIGS-CHLD plants. Furthermore, the results of metabolite profiling indicate a tight correlation between primary metabolic pathways and Mg chelatase activity. We also found that CHLD induces a feedback-regulated change of the transcription of photosynthesis-associated nuclear genes. CHLD and CHLI silencing resulted in a rapid reduction of photosynthetic proteins. Taken together, Mg chelatase is not only a key regulator of tetrapyrrole biosynthesis but its activity also correlates with ROS homeostasis, primary interorganellar metabolism and retrograde signaling in plant cells. PMID:23416492

  4. A High Throughput Barley Stripe Mosaic Virus Vector for Virus Induced Gene Silencing in Monocots and Dicots

    PubMed Central

    Yan, Lijie; Jackson, Andrew O.; Liu, Zhiyong; Han, Chenggui; Yu, Jialin; Li, Dawei

    2011-01-01

    Barley stripe mosaic virus (BSMV) is a single-stranded RNA virus with three genome components designated alpha, beta, and gamma. BSMV vectors have previously been shown to be efficient virus induced gene silencing (VIGS) vehicles in barley and wheat and have provided important information about host genes functioning during pathogenesis as well as various aspects of genes functioning in development. To permit more effective use of BSMV VIGS for functional genomics experiments, we have developed an Agrobacterium delivery system for BSMV and have coupled this with a ligation independent cloning (LIC) strategy to mediate efficient cloning of host genes. Infiltrated Nicotiana benthamiana leaves provided excellent sources of virus for secondary BSMV infections and VIGS in cereals. The Agro/LIC BSMV VIGS vectors were able to function in high efficiency down regulation of phytoene desaturase (PDS), magnesium chelatase subunit H (ChlH), and plastid transketolase (TK) gene silencing in N. benthamiana and in the monocots, wheat, barley, and the model grass, Brachypodium distachyon. Suppression of an Arabidopsis orthologue cloned from wheat (TaPMR5) also interfered with wheat powdery mildew (Blumeria graminis f. sp. tritici) infections in a manner similar to that of the A. thaliana PMR5 loss-of-function allele. These results imply that the PMR5 gene has maintained similar functions across monocot and dicot families. Our BSMV VIGS system provides substantial advantages in expense, cloning efficiency, ease of manipulation and ability to apply VIGS for high throughput genomics studies. PMID:22031834

  5. Green Tea Phenolic Epicatechins Inhibit Hepatitis C Virus Replication via Cycloxygenase-2 and Attenuate Virus-Induced Inflammation

    PubMed Central

    Lin, Ying-Ting; Wu, Yu-Hsuan; Tseng, Chin-Kai; Lin, Chun-Kuang; Chen, Wei-Chun; Hsu, Yao-Chin; Lee, Jin-Ching

    2013-01-01

    Chronic hepatitis C virus (HCV) infection is the leading risk factor for hepatocellular carcinoma (HCC) and chronic liver disease worldwide. Green tea, in addition to being consumed as a healthy beverage, contains phenolic catechins that have been used as medicinal substances. In the present study, we illustrated that the epicatechin isomers (+)-epicatechin and (−)-epicatechin concentration-dependently inhibited HCV replication at nontoxic concentrations by using in vitro cell-based HCV replicon and JFH-1 infectious systems. In addition to significantly suppressing virus-induced cyclooxygenase-2 (COX-2) expression, our results revealed that the anti-HCV activity of the epicatechin isomers occurred through the down-regulation of COX-2. Furthermore, both the epicatechin isomers additively inhibited HCV replication in combination with either interferon-α or viral enzyme inhibitors [2′-C-methylcytidine (NM-107) or telaprevir]. They also had prominent anti-inflammatory effects by inhibiting the gene expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and inducible nitrite oxide synthase as well as the COX-2 in viral protein-expressing hepatoma Huh-7 cells. Collectively, (+)-epicatechin and (−)-epicatechin may serve as therapeutic supplements for treating HCV-related diseases. PMID:23365670

  6. Epstein-Barr virus-induced gene 3 (EBI3) polymorphisms and expression are associated with susceptibility to pulmonary tuberculosis.

    PubMed

    Zheng, Ruijuan; Liu, Haipeng; Song, Peng; Feng, Yonghong; Qin, Lianhua; Huang, Xiaochen; Chen, Jianxia; Yang, Hua; Liu, Zhonghua; Cui, Zhenglin; Hu, Zhongyi; Ge, Baoxue

    2015-07-01

    Tuberculosis (TB) remains a major global health problem and host genetic factors play a critical role in susceptibility and resistance to TB. The aim of this study was to identify novel candidate genes associated with TB susceptibility. We performed a population-based case-control study to genotype 13 tag SNPs spanning Epstein-Barr virus-induced gene 3 (EBI3), colony stimulating factor 2 (CSF2), IL-4, interferon beta 1 (IFNB1), chemokine (C-X-C motif) ligand 14 (CXCL14) and myeloid differentiation primary response gene 88 (Myd88) genes in 435 pulmonary TB patients and 375 health donors from China. We observed that EBI3 gene rs4740 polymorphism was associated with susceptibility to pulmonary tuberculosis (PTB) and the allele G was associated with a protective effect against PTB. Furthermore, EBI3 deficiency led to reduced bacterial burden and histopathological impairment in the lung of mice infected with Mycobacterium bovis BCG. Meanwhile, higher abundance of EBI3 was observed in the granuloma of PTB patients and in the lung tissue of BCG-infected mice. Of note, the expression of EBI3 in macrophages was remarkably induced by mycobacteria infection at both mRNA and protein level. In conclusion, EBI3 gene rs4740 polymorphism is closely associated with susceptibility to PTB and the elevation and enrichment of EBI3 in the lung which at least partially derived from macrophages may contribute to the exacerbation of mycobacterial infection. PMID:25937126

  7. Virus-induced gene silencing-based functional verification of six genes associated with vernalization in wheat.

    PubMed

    Feng, Ya-Lan; Wang, Ke-Tao; Ma, Chao; Zhao, Yong-Ying; Yin, Jun

    2015-03-20

    Vernalization requirement is an important characteristic in crop breeding. Wheat is a widely grown crop in the world that possesses enormous economic significance. To better understand the gene networks in vernalization process, we performed a high-throughput RNA sequencing analysis comparing the transcriptomes of spring and winter wheat cultivars, with and without vernalization (unpublished data). In this study, we selected six unigenes (CL14010, CL12788, CL176, Unigene 16777, CL8746 and Unigene10196) from our transcriptome analysis based on their expression differences to further characterize their function. Transient silencing of the six unigenes individually were achieved through virus-induced gene silencing (VIGS) using BSMV vector. The period from germination to spike differentiation were recorded and compared between plants underwent VIGS silencing and the control. Our result showed that VIGS of the six unigenes significantly shortened the period from seedling to double ridge (DR) stage. Resulting in SD period ranging from 59.8 ± 0.60 to 65.8 ± 0.48 days, compared to 85.0 ± 0.73 days in the control. The results indicated that these six unigenes function as suppressors in vernalization process and silence or down-regulation of these genes promoted flower development in wheat. Further characterization of these six unigenes and their function in vernalization and flowering control is needed. PMID:25707852

  8. Decreased Diversity of the Oral Microbiota of Patients with Hepatitis B Virus-Induced Chronic Liver Disease: A Pilot Project

    PubMed Central

    Ling, Zongxin; Liu, Xia; Cheng, Yiwen; Jiang, Xiawei; Jiang, Haiyin; Wang, Yuezhu; Li, Lanjuan

    2015-01-01

    Increasing evidence suggests that altered gut microbiota is implicated in the pathogenesis of hepatitis B virus-induced chronic liver disease (HBV-CLD). However, the structure and composition of the oral microbiota of patients with HBV-CLD remains unclear. High-throughput pyrosequencing showed that decreased oral bacterial diversity was found in patients with HBV-CLD. The Firmicutes/Bacteroidetes ratio was increased significantly, which indicated that dysbiosis of the oral microbiota participated in the process of HBV-CLD development. However, the changing patterns of the oral microbiota in patients with HBV-induced liver cirrhosis (LC) were almost similar to patients with chronic hepatitis B (CHB). HBV infection resulted in an increase in potential H2S- and CH3SH-producing phylotypes such as Fusobacterium, Filifactor, Eubacterium, Parvimonas and Treponema, which might contribute to the increased oral malodor. These key oral-derived phylotypes might invade into the gut as opportunistic pathogens and contribute to altering the composition of the gut microbiota. This study provided important clues that dysbiosis of the oral microbiota might be involved in the development of HBV-CLD. Greater understanding of the relationships between the dysbiosis of oral microbiota and the development of HBV-CLD might facilitate the development of non-invasive differential diagnostic procedures and targeted treatments of HBV-CLD patients harbouring specific oral phylotypes. PMID:26606973

  9. Virus-induced gene silencing unravels multiple transcription factors involved in floral growth and development in Phalaenopsis orchids

    PubMed Central

    Hsieh, Ming-Hsien; Pan, Zhao-Jun; Lai, Pei-Han; Lu, Hsiang-Chia; Yeh, Hsin-Hung; Hsu, Chia-Chi; Wu, Wan-Lin; Chung, Mei-Chu; Wang, Shyh-Shyan; Chen, Wen-Huei; Chen, Hong-Hwa

    2013-01-01

    Orchidaceae, one of the largest angiosperm families, has significant commercial value. Isolation of genes involved in orchid floral development and morphogenesis, scent production, and colouration will advance knowledge of orchid flower formation and facilitate breeding new varieties to increase the commercial value. With high-throughput virus-induced gene silencing (VIGS), this study identified five transcription factors involved in various aspects of flower morphogenesis in the orchid Phalaenopsis equestris. These genes are PeMADS1, PeMADS7, PeHB, PebHLH, and PeZIP. Silencing PeMADS1 and PebHLH resulted in reduced flower size together with a pelaloid column containing petal-like epidermal cells and alterations of epidermal cell arrangement in lip lateral lobes, respectively. Silencing PeMADS7, PeHB, and PeZIP alone resulted in abortion of the first three fully developed flower buds of an inflorescence, which indicates the roles of the genes in late flower development. Furthermore, double silencing PeMADS1 and PeMADS6, C- and B-class MADS-box genes, respectively, produced a combinatorial phenotype with two genes cloned in separate vectors. Both PeMADS1 and PeMADS6 are required to ensure the normal development of the lip and column as well as the cuticle formation on the floral epidermal cell surface. Thus, VIGS allows for unravelling the interaction between two classes of MADS transcription factors for dictating orchid floral morphogenesis. PMID:23956416

  10. Immunopathology of malaria*

    PubMed Central

    Voller, Alister

    1974-01-01

    Antibodies with different spectra of reactivity are produced during malarial infections and marked changes in IgG and IgM levels occur. In addition malaria elicits serological changes that are usually associated with connective tissue disease. The excessive anaemia associated with malaria may, in part, be an autoimmune phenomenon. Transient nephritis accompanies many plasmodial infections but chronic malarial nephrotic syndrome is specifically associated with quartan malaria. Malarial infection leads to splenomegaly, the most extreme form of which is idiopathic tropical splenomegaly, which probably represents an aberrant immune response to the infection. Malaria can affect the humoral immune response to unrelated antigens and infectious agents. This may be relevant to the etiology of Burkitt's lymphoma. During pregnancy there is some loss of acquired immunity to P. falciparum and the placenta appears to be an immunologically privileged site for the multiplication of this parasite. PMID:4216408

  11. Expression of Epstein–Barr virus-induced gene 3 and other interleukin-12-related molecules by human intestinal epithelium

    PubMed Central

    Maaser, Christian; Egan, Laurence J; Birkenbach, Mark P; Eckmann, Lars; Kagnoff, Martin F

    2004-01-01

    Antigen-presenting cells, including dendritic cells, monocytes and macrophages, produce members of the interleukin-12 (IL-12) family that are important in initiating and maintaining cell-mediated immune responses. These include IL-12p35 and p19 that dimerize with IL-12p40 to form IL-12 (also termed IL-12p75) and IL-23, respectively, and Epstein–Barr virus-induced gene 3 (EBI3) protein (a protein related to IL-12p40), that forms a dimer with p28, termed IL-27. Intestinal epithelial cells, which are the initial site of contact between the host and enteric pathogens, can act as antigen-presenting cells, and are known to express mediators important in inflammatory and immune responses. In the current studies, we hypothesized that intestinal epithelial cells express members of the IL-12 family, which can function as an early signalling system important in mucosal immunity. Using in vitro and in vivo model systems of human intestinal epithelium, we demonstrate the regulated expression of EBI3, IL-12p35 and p19 by human intestinal epithelial cells. However, intestinal epithelial cells do not coexpress IL-12p40 or p28 that are required to generate heterodimeric IL-12p75, IL-23 and IL-27. To the extent that IL-12p35, p19 and EBI3 cannot form IL-12p75, IL-23 or IL-27 heterodimers in intestinal epithelial cells, these data suggest that those cells may express other, currently unknown, molecules that can associate with EBI3, IL-12p35 and/or p19 or, alternatively, intestinal epithelial cells may release IL-12-related molecules that by themselves, or in combination with other molecules in the mucosal microenvironment, mediate biological activities. PMID:15196212

  12. Anti-apoptotic Bcl-XL but not Mcl-1 contributes to protection against virus-induced apoptosis.

    PubMed

    Ohmer, Michaela; Weber, Arnim; Sutter, Gerd; Ehrhardt, Katrin; Zimmermann, Albert; Häcker, Georg

    2016-01-01

    Infection of mammalian cells with viruses often induces apoptosis. How the recognition of viruses leads to apoptosis of the infected cell and which host cell factors regulate this cell death is incompletely understood. In this study, we focussed on two major anti-apoptotic proteins of the host cell, whose abundance and activity are important for cell survival, the Bcl-2-like proteins Mcl-1 and Bcl-XL. During infection of epithelial cells and fibroblasts with modified vaccinia virus Ankara (MVA), Mcl-1 protein levels dropped but the MVA Bcl-2-like protein F1L could replace Mcl-1 functionally; a similar activity was found in vaccinia virus (VACV)-infected cells. During infection with murine cytomegalovirus (MCMV), Mcl-1-levels were not reduced but a viral Mcl-1-like activity was also generated. Infection of mouse macrophages with any of these viruses, on the other hand, induced apoptosis. Virus-induced macrophage apoptosis was unaltered in the absence of Mcl-1. However, apoptosis was substantially increased in infected Bcl-XL-deficient macrophages or macrophages treated with the Bcl-2/Bcl-XL-inhibitor ABT-737. Genetic loss of Bcl-XL or treatment of macrophages with ABT-737 reduced the generation of infectious VACV. These data show that Mcl-1 is dispensable for the regulation of apoptosis during infection with different large DNA viruses, either because the viruses replace its function (in fibroblasts and epithelial cells) or because the pro-apoptotic activity generated by the infection appears not to be blocked by it (in macrophages). Bcl-XL, on the other hand, can be important to maintain survival of virus-infected cells, and its activity can determine outcome of the infection. PMID:27537523

  13. JC virus induces altered patterns of cellular gene expression: Interferon-inducible genes as major transcriptional targets

    SciTech Connect

    Verma, Saguna; Ziegler, Katja; Ananthula, Praveen; Co, Juliene K.G.; Frisque, Richard J.; Yanagihara, Richard; Nerurkar, Vivek R. . E-mail: nerurkar@pbrc.hawaii.edu

    2006-02-20

    Human polyomavirus JC (JCV) infects 80% of the population worldwide. Primary infection, typically occurring during childhood, is asymptomatic in immunocompetent individuals and results in lifelong latency and persistent infection. However, among the severely immunocompromised, JCV may cause a fatal demyelinating disease, progressive multifocal leukoencephalopathy (PML). Virus-host interactions influencing persistence and pathogenicity are not well understood, although significant regulation of JCV activity is thought to occur at the level of transcription. Regulation of the JCV early and late promoters during the lytic cycle is a complex event that requires participation of both viral and cellular factors. We have used cDNA microarray technology to analyze global alterations in gene expression in JCV-permissive primary human fetal glial cells (PHFG). Expression of more than 400 cellular genes was altered, including many that influence cell proliferation, cell communication and interferon (IFN)-mediated host defense responses. Genes in the latter category included signal transducer and activator of transcription 1 (STAT1), interferon stimulating gene 56 (ISG56), myxovirus resistance 1 (MxA), 2'5'-oligoadenylate synthetase (OAS), and cig5. The expression of these genes was further confirmed in JCV-infected PHFG cells and the human glioblastoma cell line U87MG to ensure the specificity of JCV in inducing this strong antiviral response. Results obtained by real-time RT-PCR and Western blot analyses supported the microarray data and provide temporal information related to virus-induced changes in the IFN response pathway. Our data indicate that the induction of an antiviral response may be one of the cellular factors regulating/controlling JCV replication in immunocompetent hosts and therefore constraining the development of PML.

  14. Protective Immunity to Vaccinia Virus Induced by Vaccination with Multiple Recombinant Outer Membrane Proteins of Intracellular and Extracellular Virions

    PubMed Central

    Fogg, Christiana; Lustig, Shlomo; Whitbeck, J. Charles; Eisenberg, Roselyn J.; Cohen, Gary H.; Moss, Bernard

    2004-01-01

    Infectious intracellular and extracellular forms of vaccinia virus have different outer membrane proteins, presenting multiple targets to the immune system. We investigated the immunogenicity of soluble forms of L1, an outer membrane protein of the intracellular mature virus, and of A33 and B5, outer membrane proteins of the extracellular enveloped virus. The recombinant proteins, in 10-μg amounts mixed with a Ribi- or saponin-type adjuvant, were administered subcutaneously to mice. Antibody titers to each protein rose sharply after the first and second boosts, reaching levels that surpassed those induced by percutaneous immunization with live vaccinia virus. Immunoglobulin G1 (IgG1) antibody predominated after the protein immunizations, indicative of a T-helper cell type 2 response, whereas live vaccinia virus induced mainly IgG2a, indicative of a T-helper cell type 1 response. Mice immunized with any one of the recombinant proteins survived an intranasal challenge with 5 times the 50% lethal dose of the pathogenic WR strain of vaccinia virus. Measurements of weight loss indicated that the A33 immunization most effectively prevented disease. The superiority of protein combinations was demonstrated when the challenge virus dose was increased 20-fold. The best protection was obtained with a vaccine made by combining recombinant proteins of the outer membranes of intracellular and extracellular virus. Indeed, mice immunized with A33 plus B5 plus L1 or with A33 plus L1 were better protected than mice immunized with live vaccinia virus. Three immunizations with the three-protein combination were necessary and sufficient for complete protection. These studies suggest the feasibility of a multiprotein smallpox vaccine. PMID:15367588

  15. Virus induced gene silencing of three putative prolyl 4-hydroxylases enhances plant growth in tomato (Solanum lycopersicum).

    PubMed

    Fragkostefanakis, Sotirios; Sedeek, Khalid E M; Raad, Maya; Zaki, Marwa Samir; Kalaitzis, Panagiotis

    2014-07-01

    Proline hydroxylation is a major posttranslational modification of hydroxyproline-rich glycoproteins (HRGPs) that is catalyzed by prolyl 4-hydroxylases (P4Hs). HRGPs such as arabinogalactan proteins (AGPs) and extensios play significant roles on cell wall structure and function and their implication in cell division and expansion has been reported. We used tobacco rattle virus (TRV)-based virus induced gene silencing to investigate the role of three tomato P4Hs, out of ten present in the tomato genome, in growth and development. Eight-days old tomato seedlings were infected with the appropriate TRV vectors and plants were allowed to grow under standard conditions for 6 weeks. Lower P4H mRNA levels were associated with lower hydroxyproline content in root and shoot tissues indicating successful gene silencing. P4H-silenced plants had longer roots and shoots and larger leaves. The increased leaf area can be attributed to increased cell division as indicated by the higher leaf epidermal cell number in SlP4H1- and SlP4H9-silenced plants. In contrast, SlP4H7-silenced plants had larger leaves due to enhanced cell expansion. Western blot analysis revealed that silencing of SlP4H7 and SlP4H9 was associated with reduced levels of JIM8-bound AGP and JIM11-bound extensin epitopes, while silencing of SlP4H1 reduced only the levels of AGP proteins. Collectively these results show that P4Hs have significant and distinct roles in cell division and expansion of tomato leaves. PMID:24803411

  16. Expression of interleukin 6 receptors and interleukin 6 mRNA by bovine leukaemia virus-induced tumour cells.

    PubMed

    Droogmans, L; Cludts, I; Cleuter, Y; Kerkhofs, P; Adam, E; Willems, L; Kettmann, R; Burny, A

    1994-11-01

    Bovine leukaemia virus (BLV) is the aetiologic agent of bovine leucosis. The virus induces malignancies of the B-cell lineage (leukaemia/lymphoma). The role played by interleukin 6 (IL-6) in the BLV-induced leukemogenesis process was evaluated. Six cell lines derived from BLV-induced tumours were tested for the expression of IL-6 receptors. Two cell lines (LB155 and YR2) display 250-300 receptor per cell (kd = 1.7 10(-10) M and 1.4 10(-10) M, respectively) whereas the other four (LB159, LB167, YR1 and M51) do not display detectable amounts of receptors. Very low (if any) expression of IL-6 receptors has been found in the case of the B lymphocytes of animals in persistent lymphocytosis (PL). Despite the presence of IL-6 receptors on the surface of LB155 and YR2 cells, no influence of exogenous IL-6 on their growth has been observed. Northern analyses indicated the presence of IL-6 transcripts only in the case of mRNA isolated from LB155 cells. Since this cell line also expresses receptors for the cytokine, an autocrine loop may exist in these cells. Experiments in which bovine and bovine epithelial cell lines were transfected with a plasmid containing the bovine IL-6 promoter controlling the expression of the reporter cat gene failed to indicate any influence of the viral transactivator p34tax on the activity of this promoter. We conclude that IL-6 receptors and IL-6 mRNA can be found in some BLV-induced tumours, but this does not correlate with viral expression in BLV-induced leukaemia/lymphoma. PMID:7893972

  17. Virus-induced gene silencing of Arabidopsis thaliana gene homologues in wheat identifies genes conferring improved drought tolerance

    PubMed Central

    Lapitan, Nora

    2013-01-01

    In a non-model staple crop like wheat (Triticum aestivumI L.), functional validation of potential drought stress responsive genes identified in Arabidopsis could provide gene targets for breeding. Virus-induced gene silencing (VIGS) of genes of interest can overcome the inherent problems of polyploidy and limited transformation potential that hamper functional validation studies in wheat. In this study, three potential candidate genes shown to be involved in abiotic stress response pathways in Arabidopsis thaliana were selected for VIGS experiments in wheat. These include Era1 (enhanced response to abscisic acid), Cyp707a (ABA 8’-hydroxylase), and Sal1 (inositol polyphosphate 1-phosphatase). Gene homologues for these three genes were identified in wheat and cloned in the viral vector barley stripe mosaic virus (BSMV) in the antisense direction, followed by rub inoculation of BSMV viral RNA transcripts onto wheat plants. Quantitative real-time PCR showed that VIGS-treated wheat plants had significant reductions in target gene transcripts. When VIGS-treated plants generated for Era1 and Sal1 were subjected to limiting water conditions, they showed increased relative water content, improved water use efficiency, reduced gas exchange, and better vigour compared to water-stressed control plants inoculated with RNA from the empty viral vector (BSMV0). In comparison, the Cyp707a-silenced plants showed no improvement over BSMV0-inoculated plants under limited water condition. These results indicate that Era1 and Sal1 play important roles in conferring drought tolerance in wheat. Other traits affected by Era1 silencing were also studied. Delayed seed germination in Era1-silenced plants suggests this gene may be a useful target for developing resistance to pre-harvest sprouting. PMID:23364940

  18. Anti-inflammatory effects of the novel inhaled phosphodiesterase type 4 inhibitor CHF6001 on virus-inducible cytokines.

    PubMed

    Edwards, Michael R; Facchinetti, Fabrizio; Civelli, Maurizio; Villetti, Gino; Johnston, Sebastian L

    2016-02-01

    Respiratory virus infections precipitate asthma and chronic obstructive pulmonary disease (COPD) exacerbations, with most exacerbations due to rhinovirus infection. Both asthma and COPD exacerbations are not well controlled by steroid therapies, and there is a much research interest in finding improved therapies or combinations of therapies for controlling exacerbations. CHF6001 is a new, inhaled highly potent and selective phosphodiesterase type 4 (PDE4) inhibitor. Using in vitro human bronchial epithelial cells (BEAS-2B), we investigated the potential anti-inflammatory effects of CHF6001 on rhinovirus (RV1B)-induced cytokines. Cytokine mRNA was measured by real-time PCR, while protein release was measured by ELISA. CHF6001 was used in a 7-point dose-response curve (1000-0.001 nmol/L) as a 1.5-h pretreatment prior to infection in comparison with roflumilast. Both roflumilast and CHF6001 reduced RV1B-induced IL-8, IL-29, IP-10, and RANTES mRNA and protein in a concentration-dependent manner. Generally, CHF6001 was 13- to 16-fold more potent (subnanomolar EC 50 values) than roflumilast at reducing IL-8, IL-29, IP-10, and RANTES mRNA and protein release, but had similar efficacies. In combination with the steroid fluticasone propionate (1 nmol/L), CHF6001 had additive effects, significantly reducing RV-induced cytokines when compared with steroid or CHF6001 alone. Combined low-dose steroid and low-dose CHF6001 had a similar efficacy as high-dose steroid or CHF6001 alone, indicating the combination had steroid and PDE4 inhibitor sparing effects. Overall results indicate that PDE4 inhibitors have anti-inflammatory activity against virus-induced inflammatory mediators and that CHF6001 is more potent than roflumilast. PMID:26977295

  19. Revelation of the IFNα, IL-10, IL-8 and IL-1β as promising biomarkers reflecting immuno-pathological mechanisms in porcine Huntington's disease model.

    PubMed

    Valekova, Ivona; Jarkovska, Karla; Kotrcova, Eva; Bucci, John; Ellederova, Zdenka; Juhas, Stefan; Motlik, Jan; Gadher, Suresh Jivan; Kovarova, Hana

    2016-04-15

    Studies on Huntington's disease (HD) demonstrated altered immune response in HD gene carriers. Using multiplexing immunoassay, we simultaneously investigated seven cytokines in secretomes of microglia and blood monocytes, cerebrospinal fluid (CSF) and serum collected from transgenic HD minipigs at pre-symptomatic disease stage. Decline in IFNα and IL-10 was observed in CSF and secretome of microglia whilst elevated IL-8 and IL-1β levels were secreted by microglia. Additionally, IL-8 was increased in serum. The proportion of mutant huntingtin in microglia may have causative impact on cytokine production. IFNα, IL-10, IL-8 and IL-1β represent promising biomarkers reflecting immuno-pathological mechanisms in porcine HD model. PMID:27049565

  20. Molecular Characterization of Oxysterol Binding to the Epstein-Barr Virus-induced Gene 2 (GPR183)*

    PubMed Central

    Benned-Jensen, Tau; Norn, Christoffer; Laurent, Stephane; Madsen, Christian M.; Larsen, Hjalte M.; Arfelt, Kristine N.; Wolf, Romain M.; Frimurer, Thomas; Sailer, Andreas W.; Rosenkilde, Mette M.

    2012-01-01

    Oxysterols are oxygenated cholesterol derivates that are emerging as a physiologically important group of molecules. Although they regulate a range of cellular processes, only few oxysterol-binding effector proteins have been identified, and the knowledge of their binding mode is limited. Recently, the family of G protein-coupled seven transmembrane-spanning receptors (7TM receptors) was added to this group. Specifically, the Epstein-Barr virus-induced gene 2 (EBI2 or GPR183) was shown to be activated by several oxysterols, most potently by 7α,25-dihydroxycholesterol (7α,25-OHC). Nothing is known about the binding mode, however. Using mutational analysis, we identify here four key residues for 7α,25-OHC binding: Arg-87 in TM-II (position II:20/2.60), Tyr-112 and Tyr-116 (positions III:09/3.33 and III:13/3.37) in TM-III, and Tyr-260 in TM-VI (position VI:16/6.51). Substituting these residues with Ala and/or Phe results in a severe decrease in agonist binding and receptor activation. Docking simulations suggest that Tyr-116 interacts with the 3β-OH group in the agonist, Tyr-260 with the 7α-OH group, and Arg-87, either directly or indirectly, with the 25-OH group, although nearby residues likely also contribute. In addition, Tyr-112 is involved in 7α,25-OHC binding but via hydrophobic interactions. Finally, we show that II:20/2.60 constitutes an important residue for ligand binding in receptors carrying a positively charged residue at this position. This group is dominated by lipid- and nucleotide-activated receptors, here exemplified by the CysLTs, P2Y12, and P2Y14. In conclusion, we present the first molecular characterization of oxysterol binding to a 7TM receptor and identify position II:20/2.60 as a generally important residue for ligand binding in certain 7TM receptors. PMID:22875855

  1. Involvement of fish signal transducer and activator of transcription 3 (STAT3) in SGIV replication and virus induced paraptosis.

    PubMed

    Huang, Xiaohong; Huang, Youhua; Yang, Ying; Wei, Shina; Qin, Qiwei

    2014-12-01

    Signal transducer and activator of transcription 3 (STAT3) is an important transcription factor which plays crucial roles in immune regulation, inflammation, cell proliferation, transformation, and other physiological processes of the organism. In this study, a novel STAT3 gene from orange spotted grouper (Ec-STAT3) was cloned and characterized. Bioinformatic analysis revealed that full-length of Ec-STAT3 was 3105-bp long and contained a 280-bp 5'UTR, a 470-bp 3'UTR, and a 2355-bp open reading frame (ORF) that encoded a 784-amino acid peptide. The deduced protein of Ec-STAT3 showed 98% identity to that of turbot (Scophthalmus maximus). Amino acid alignment showed that Ec-STAT3 contained four conserved domains, including a protein interaction domain, a coiled coil domain, a DNA binding domain, and an SH2 domain. Quantitative real-time PCR analysis showed that the highest expression level was detected in the liver, followed by skin and spleen. After injection with Singapore grouper iridovirus (SGIV), the transcript of Ec-STAT3 in spleen was increased significantly. To further explore the function of Ec-STAT3, we investigated the roles of Ec-STAT3 in SGIV infection in vitro. Immune fluorescence analysis indicated that SGIV infection altered the distribution of phosphorylated Ec-STAT3 in nucleus, and a small part of phosphorylated Ec-STAT3 was associated with virus assembly sites, suggesting that Ec-STAT3 might be important for SGIV infection. Using STAT3 specific inhibitor, S3I-201, we found that inhibition of Ec-STAT3 activation decreased the SGIV replication significantly. Moreover, inhibition of Ec-STAT3 activation obviously altered SGIV infection induced cell cycle arrest and the expression of pro-survival genes, including Bcl-2, Bcl-xL and Bax inhibitor. Together, our results firstly demonstrated the critical roles of fish STAT3 in DNA virus replication and virus induced paraptosis, but also provided new insights into the mechanism of iridovirus pathogenesis

  2. Genetic determinants of feline leukemia virus-induced lymphoid tumors: patterns of proviral insertion and gene rearrangement.

    PubMed

    Tsatsanis, C; Fulton, R; Nishigaki, K; Tsujimoto, H; Levy, L; Terry, A; Spandidos, D; Onions, D; Neil, J C

    1994-12-01

    The genetic basis of feline leukemia virus (FeLV)-induced lymphoma was investigated in a series of 63 lymphoid tumors and tumor cell lines of presumptive T-cell origin. These were examined for virus-induced rearrangements of the c-myc, flvi-2 (bmi-1), fit-1, and pim-1 loci, for T-cell receptor (TCR) gene rearrangements, and for the presence of env recombinant FeLV (FeLV-B). The myc locus was most frequently affected in naturally occurring lymphomas (32%; n = 38) either by transduction (21%) or by proviral insertion (11%). Proviral insertions were also common at flvi-2 (24%). The two other loci were occupied in a smaller number of the naturally occurring tumors (fit-1, 8%; pim-1, 5%). Examination of the entire set of tumors showed that significant numbers were affected at two (19%) or three (5%) of the loci. Occupation of the fit-1 locus was observed most frequently in tumors induced by FeLV-myc strains, while flvi-2 insertions occurred with similar frequency in the presence or absence of obvious c-myc activation. These results suggest a hierarchy of mutational events in the genesis of feline T-cell lymphomas by FeLV and implicate insertion at fit-1 as a late progression step. The strongest links observed were with T-cell development, as monitored by rearrangement status of the TCR beta-chain gene, which was positively associated with activation of myc (P < 0.001), and with proviral insertion at flvi-2 (P = 0.02). This analysis also revealed a genetically distinct subset of thymic lymphomas with unrearranged TCR beta-chain genes in which the known target loci were involved very infrequently. The presence of env recombinant FeLV (FeLV-B) showed a negative correlation with proviral insertion at fit-1, possibly due to the rapid onset of these tumors. These results shed further light on the multistep process of FeLV leukemogenesis and the relationships between lymphoid cell maturation and susceptibility to FeLV transformation. PMID:7966623

  3. Identification of Novel Compounds Inhibiting Chikungunya Virus-Induced Cell Death by High Throughput Screening of a Kinase Inhibitor Library

    PubMed Central

    Gomes, Rafael G. B.; da Silva, Camila T.; Taniguchi, Juliana B.; No, Joo Hwan; Lombardot, Benoit; Schwartz, Olivier; Hansen, Michael A. E.; Freitas-Junior, Lucio H.

    2013-01-01

    antiviral activity - inhibition of virus-induced CPE - likely by targeting kinases involved in apoptosis. PMID:24205414

  4. T cell-mediated hepatitis in mice infected with lymphocytic choriomeningitis virus. Liver cell destruction by H-2 class I-restricted virus-specific cytotoxic T cells as a physiological correlate of the /sup 51/Cr-release assay

    SciTech Connect

    Zinkernagel, R.M.; Haenseler, E.; Leist, T.; Cerny, A.; Hengartner, H.; Althage, A.

    1986-10-01

    A model for immunologically T cell-mediated hepatitis was established in mice infected with lymphocytic choriomeningitis virus (LCMV). The severity of hepatitis was monitored histologically and by determination of changes in serum levels of the enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutamate dehydrogenase (GLDH), and alkaline phosphatase (AP). Kinetics of histological disease manifestations, increases of liver enzyme levels in the serum, and cytotoxic T cell activities in livers and spleens all correlated and were dependent upon several parameters: LCMV-isolate; LCMV-WE caused extensive hepatitis, LCMV-Armstrong virtually none. Virus dose. Route of infection; i.v. or i.p. infection caused hepatitis, whereas infection into the footpad did not. The general genetic background of the murine host; of the strains tested, Swiss mice and A-strain mice were more susceptible than C57BL or CBA mice; BALB/c and DBA/2 mice were least susceptible. The degree of immunocompetence of the murine host; T cell deficient nu/nu mice never developed hepatitis, whereas nu/+ or +/+ mice always did. B cell-depleted anti-IgM-treated mice developed immune-mediated hepatitis comparably or even more extensively than control mice. Local cytotoxic T cell activity; mononuclear cells isolated from livers during the period of overt hepatitis were two to five times more active than equal numbers of spleen cells. Adoptive transfer of nylon wool-nonadherent anti-Thy-1.2 and anti-Lyt-2 plus C-sensitive, anti-L3T4 plus C-resistant lymphocytes into irradiated mice preinfected with LCMV-WE caused a rapid time- and dose-dependent linear increase of serum enzyme levels. This increase was caused by adoptive transfer of lymphocytes if immune cell donors and recipient mice shared class I, but not when they shared class II histocompatibility antigens.

  5. Antibodies to CD9, a Tetraspan Transmembrane Protein, Inhibit Canine Distemper Virus-Induced Cell-Cell Fusion but Not Virus-Cell Fusion

    PubMed Central

    Schmid, Erik; Zurbriggen, Andreas; Gassen, Uta; Rima, Bert; ter Meulen, Volker; Schneider-Schaulies, Jürgen

    2000-01-01

    Canine distemper virus (CDV) causes a life-threatening disease in several carnivores including domestic dogs. Recently, we identified a molecule, CD9, a member of the tetraspan transmembrane protein family, which facilitates, and antibodies to which inhibit, the infection of tissue culture cells with CDV (strain Onderstepoort). Here we describe that an anti-CD9 monoclonal antibody (MAb K41) did not interfere with binding of CDV to cells and uptake of virus. In addition, in single-step growth experiments, MAb K41 did not induce differences in the levels of viral mRNA and proteins. However, the virus release of syncytium-forming strains of CDV, the virus-induced cell-cell fusion in lytically infected cultures, and the cell-cell fusion of uninfected with persistently CDV-infected HeLa cells were strongly inhibited by MAb K41. These data indicate that anti-CD9 antibodies selectively block virus-induced cell-cell fusion, whereas virus-cell fusion is not affected. PMID:10906209

  6. Analysis of herpes simplex virus-induced mRNA destabilizing activity using an in vitro mRNA decay system.

    PubMed Central

    Sorenson, C M; Hart, P A; Ross, J

    1991-01-01

    Most host mRNAs are degraded soon after infection of cells with herpes simplex virus type 1 (HSV-1). This early shutoff or early destabilization response is induced by a virion component, the virion host shutoff (vhs) protein. HSV-1 mutants, vhs1 and vhs-delta Sma, which produce defective or inactive vhs protein, fail to induce early shutoff. We have used an in vitro mRNA decay system to analyze the destabilization process. Polysomes from uninfected human erythroleukemia cells, used as a source of target mRNAs, were mixed with polysomes or with post-polysomal supernatant (S130) from HSV-1- or mock-infected murine erythroleukemia cells. Normally stable gamma-globin mRNA was destabilized by approximately 15-fold with S130 from wild-type virus-infected cells but was not destabilized with S130 from mock-infected cells or from cells infected with either of the two HSV mutants. The virus-induced destabilizing activity had no significant effect on the in vitro half-lives of two normally unstable mRNAs, histone and c-myc. No destabilizing activity was detected in polysomes from infected cells. We conclude that a virus-induced destabilizer activity can function in vitro, is located in the S130 of infected cells, and accelerates the decay rates of some, but not all, polysome-associated host mRNAs. Images PMID:1653415

  7. Peptide vaccination of mice immune to LCMV or vaccinia virus causes serious CD8+ T cell-mediated, TNF-dependent immunopathology

    PubMed Central

    Liu, Fei; Feuer, Ralph; Hassett, Daniel E.; Whitton, J. Lindsay

    2006-01-01

    CD8+ T cells play a key role in clearing primary virus infections and in protecting against subsequent challenge. The potent antiviral effects of these cells make them important components of vaccine-induced immunity and, because of this, peptide vaccines often contain epitopes designed to induce strong CD8+ T cell responses. However, the same effector functions that protect the host also can be harmful if they are not tightly regulated, and virus-specific CD8+ T cells are a frequent cause of immunopathology. Here, we report that the administration of peptide to virus-immune recipient mice can lead to the synchronous activation of preexisting virus-specific CD8+ T cells with serious, and even lethal, consequences. Mice infected with LCMV or vaccinia virus developed rapid and profound hypothermia following injection of cognate synthetic peptides, and LCMV-infected mice frequently died within hours. Detailed analyses of the LCMV infected mice revealed enterocyte apoptosis and implicated TNF produced by peptide-specific CD8+ T cells as the major mediator of disease. The caspase inhibitor zVADfmk had no demonstrable effect on the development of hypothermia, but diminished enterocyte apoptosis and greatly reduced the number of deaths. These findings, if similarly observed in patients, counsel caution when administering powerful immunogens such as peptide vaccines to individuals who may have a large preexisting pool of epitope-specific CD8+ T cells. PMID:16424939

  8. Apple latent spherical virus vectors for reliable and effective virus-induced gene silencing among a broad range of plants including tobacco, tomato, Arabidopsis thaliana, cucurbits, and legumes

    SciTech Connect

    Igarashi, Aki; Yamagata, Kousuke; Sugai, Tomokazu; Takahashi, Yukari; Sugawara, Emiko; Tamura, Akihiro; Yaegashi, Hajime; Yamagishi, Noriko; Takahashi, Tsubasa; Isogai, Masamichi; Takahashi, Hideki; Yoshikawa, Nobuyuki

    2009-04-10

    Apple latent spherical virus (ALSV) vectors were evaluated for virus-induced gene silencing (VIGS) of endogenous genes among a broad range of plant species. ALSV vectors carrying partial sequences of a subunit of magnesium chelatase (SU) and phytoene desaturase (PDS) genes induced highly uniform knockout phenotypes typical of SU and PDS inhibition on model plants such as tobacco and Arabidopsis thaliana, and economically important crops such as tomato, legume, and cucurbit species. The silencing phenotypes persisted throughout plant growth in these plants. In addition, ALSV vectors could be successfully used to silence a meristem gene, proliferating cell nuclear antigen and disease resistant N gene in tobacco and RCY1 gene in A. thaliana. As ALSV infects most host plants symptomlessly and effectively induces stable VIGS for long periods, the ALSV vector is a valuable tool to determine the functions of interested genes among a broad range of plant species.

  9. Lack of essential role of NF-kappa B p50, RelA, and cRel subunits in virus-induced type 1 IFN expression.

    PubMed

    Wang, Xingyu; Hussain, Sofia; Wang, Emilie-Jeanne; Wang, Xiuyan; Li, Ming O; García-Sastre, Adolfo; Beg, Amer A

    2007-06-01

    Type 1 IFNs (IFN-alphabeta) play pivotal roles in the host antiviral response and in TLR-induced signaling. IFN regulatory factor (IRF) and NF-kappaB transcription factors are thought to be crucial for virus-induced mRNA expression of IFN-beta. Although recent studies have demonstrated essential roles for IRF3 and IRF7, the definitive role of NF-kappaB factors in IFN-beta (or IFN-alpha) expression remains unknown. Using mice deficient in distinct members of the NF-kappaB family, we investigated NF-kappaB function in regulating type 1 IFN expression in response to Sendai virus and Newcastle disease virus infection. Surprisingly, IFN-beta and IFN-alpha expression was strongly induced following virus infection of mouse embryonic fibroblasts (MEFs) from p50(-/-), RelA/p65(-/-), cRel(-/-), p50(-/-)cRel(-/-), and p50(-/-)RelA(-/-) mice. Compared with wild-type MEFs, only RelA(-/-) and p50(-/-)RelA(-/-) MEFs showed a modest reduction in IFN-beta expression. To overcome functional redundancy between different NF-kappaB subunits, we expressed a dominant-negative IkappaBalpha protein in p50(-/-)RelA(-/-) MEFs to inhibit activation of remaining NF-kappaB subunits. Although viral infection of these cells failed to induce detectable NF-kappaB activity, both Sendai virus and Newcastle disease virus infection led to robust IFN-beta expression. Virus infection of dendritic cells or TLR9-ligand CpG-D19 treatment of plasmacytoid dendritic cells from RelA(-/-) or p50(-/-)cRel(-/-) mice also induced robust type 1 IFN expression. Our findings therefore indicate that NF-kappaB subunits p50, RelA, and cRel play a relatively minor role in virus-induced type 1 IFN expression. PMID:17513724

  10. The presence of tomato leaf curl Kerala virus AC3 protein enhances viral DNA replication and modulates virus induced gene-silencing mechanism in tomato plants

    PubMed Central

    2011-01-01

    Background Geminiviruses encode few viral proteins. Most of the geminiviral proteins are multifunctional and influence various host cellular processes for the successful viral infection. Though few viral proteins like AC1 and AC2 are well characterized for their multiple functions, role of AC3 in the successful viral infection has not been investigated in detail. Results We performed phage display analysis with the purified recombinant AC3 protein with Maltose Binding Protein as fusion tag (MBP-AC3). Putative AC3 interacting peptides identified through phage display were observed to be homologous to peptides of proteins from various metabolisms. We grouped these putative AC3 interacting peptides according to the known metabolic function of the homologous peptide containing proteins. In order to check if AC3 influences any of these particular metabolic pathways, we designed vectors for assaying DNA replication and virus induced gene-silencing of host gene PCNA. Investigation with these vectors indicated that AC3 enhances viral replication in the host plant tomato. In the PCNA gene-silencing experiment, we observed that the presence of functional AC3 ORF strongly manifested the stunted phenotype associated with the virus induced gene-silencing of PCNA in tomato plants. Conclusions Through the phage display analysis proteins from various metabolic pathways were identified as putative AC3 interacting proteins. By utilizing the vectors developed, we could analyze the role of AC3 in viral DNA replication and host gene-silencing. Our studies indicate that AC3 is also a multifunctional protein. PMID:21496351

  11. Delay of vaccinia virus-induced apoptosis in nonpermissive Chinese hamster ovary cells by the cowpox virus CHOhr and adenovirus E1B 19K genes.

    PubMed Central

    Ink, B S; Gilbert, C S; Evan, G I

    1995-01-01

    The infection of vaccinia virus in Chinese hamster ovary (CHO) cells produces a rapid shutdown in protein synthesis, and the infection is abortive (R.R. Drillien, D. Spehner, and A. Kirn, Virology 111:488-499, 1978; D.E. Hruby, D.L. Lynn, R. Condit, and J.R. Kates, J. Gen. Virol. 47:485-488, 1980). Cowpox virus, which can productively infect CHO cells, had previously been shown to contain a host range gene, CHOhr, which confers on vaccinia virus the ability to replicate in CHO cells (D. Spehner, S. Gillard, R. Drillien, and A. Kirn, J. Virol. 62:1297-1304, 1988). We found that CHO cells underwent apoptosis when infected with vaccinia virus. The expression of the CHOhr gene in vaccinia virus allowed for the expression of late virus genes. CHOhr also delayed or prevented vaccinia virus-induced apoptosis in CHO cells such that there was sufficient time for replication of the virus before the cell died. The E1B 19K gene from adenovirus also delayed vaccinia virus-induced apoptosis; however, there was no detectable expression of late virus genes. Furthermore, E1B 19K also delayed cell death in CHO cells which had been productively infected with vaccinia virus. This study identifies a new antiapoptotic gene from cowpox virus, CHOhr, for which the protein contains an ankyrin-like repeat and shows no significant homology to other proteins. This work also indicates that an antiapoptotic gene from one virus family can delay cell death in an infection of a virus from a different family. PMID:7815529

  12. Helicobacter pylori Induced Gastric Immunopathology Is Associated with Distinct Microbiota Changes in the Large Intestines of Long-Term Infected Mongolian Gerbils

    PubMed Central

    Heimesaat, Markus M.; Fischer, André; Plickert, Rita; Wiedemann, Tobias; Loddenkemper, Christoph; Göbel, Ulf B.

    2014-01-01

    Background Gastrointestinal (GI) inflammation in mice and men are frequently accompanied by distinct changes of the GI microbiota composition at sites of inflammation. Helicobacter (H.) pylori infection results in gastric immunopathology accompanied by colonization of stomachs with bacterial species, which are usually restricted to the lower intestine. Potential microbiota shifts distal to the inflammatory process following long-term H. pylori infection, however, have not been studied so far. Methodology/Principal Findings For the first time, we investigated microbiota changes along the entire GI tract of Mongolian gerbils after 14 months of infection with H. pylori B8 wildtype (WT) or its isogenic ΔcagY mutant (MUT) strain which is defective in the type IV secretion system and thus unable to modulate specific host pathways. Comprehensive cultural analyses revealed that severe gastric diseases such as atrophic pangastritis and precancerous transformations were accompanied by elevated luminal loads of E. coli and enterococci in the caecum and together with Bacteroides/Prevotella spp. in the colon of H. pylori WT, but not MUT infected gerbils as compared to naïve animals. Strikingly, molecular analyses revealed that Akkermansia, an uncultivable species involved in mucus degradation, was exclusively abundant in large intestines of H. pylori WT, but not MUT infected nor naïve gerbils. Conclusion/Significance Taken together, long-term infection of Mongolian gerbils with a H. pylori WT strain displaying an intact type IV secretion system leads to distinct shifts of the microbiota composition in the distal uninflamed, but not proximal inflamed GI tract. Hence, H. pylori induced immunopathogenesis of the stomach, including hypochlorhydria and hypergastrinemia, might trigger large intestinal microbiota changes whereas the exact underlying mechanisms need to be further unraveled. PMID:24941045

  13. Chronic graft-versus-host disease in the rat radiation chimera: I. clinical features, hematology, histology, and immunopathology in long-term chimeras

    SciTech Connect

    Beschorner, W.E.; Tutschka, P.J.; Santos, G.W.

    1982-04-01

    The clinical features, pathology, and immunopathology of chronic graft-versus-host disease (GVHD) developing in the long-term rat radiation chimera are described. At 6 to 12 months post-transplant, the previously stable ACI/LEW chimeras developed patchy to diffuse severe hair loss and thickened skin folds, and had microscopic features resembling scleroderma, Sjogren's syndrome, and chronic hepatitis. Skin histology showed dermal inflammation and acanthosis with atrophy of the appendages, with progression to dermal sclerosis. The liver revealed chronic hepatitis with bile duct injury and proliferation and periportal piecemeal necrosis. The tongue had considerable submucosal inflammation, muscular necrosis, and atrophy and arteritis. The serous salivary glands, lacrimal glands, and bronchi had lymphocytic inflammation and injury to duct, acinar, and mucosal columnar epithelium. The thymus had lymphocyte depletion of the medulla with prominent epithelium. The spleen and lymph nodes had poorly developed germinal centers but increased numbers of plasma cells. IgM was observed along the basement membrane and around the basal cells of the skin and tongue and along the basement membrane of the bile ducts. IgM was present also in the arteries of the tongue. Immunoglobulins eluted from the skin, cross-reacted with the bile duct epithelium and usually with both ACI and Lewis skin. Increased titers of speckled antinuclear antibodies were present in the serum of rats with chronic (GVHD). Chronic GVHD in the long-term rat radiation chimera is very similar to human chronic GVHD and is a potentially excellent model for autoimmune disorders including scleroderma, Sjorgren's syndrome, and chronic hepatitis.

  14. Virus-Induced Gene Silencing Using Tobacco Rattle Virus as a Tool to Study the Interaction between Nicotiana attenuata and Rhizophagus irregularis

    PubMed Central

    Groten, Karin; Pahari, Nabin T.; Xu, Shuqing; Miloradovic van Doorn, Maja; Baldwin, Ian T.

    2015-01-01

    Most land plants live in a symbiotic association with arbuscular mycorrhizal fungi (AMF) that belong to the phylum Glomeromycota. Although a number of plant genes involved in the plant-AMF interactions have been identified by analyzing mutants, the ability to rapidly manipulate gene expression to study the potential functions of new candidate genes remains unrealized. We analyzed changes in gene expression of wild tobacco roots (Nicotiana attenuata) after infection with mycorrhizal fungi (Rhizophagus irregularis) by serial analysis of gene expression (SuperSAGE) combined with next generation sequencing, and established a virus-induced gene-silencing protocol to study the function of candidate genes in the interaction. From 92,434 SuperSAGE Tag sequences, 32,808 (35%) matched with our in-house Nicotiana attenuata transcriptome database and 3,698 (4%) matched to Rhizophagus genes. In total, 11,194 Tags showed a significant change in expression (p<0.05, >2-fold change) after infection. When comparing the functions of highly up-regulated annotated Tags in this study with those of two previous large-scale gene expression studies, 18 gene functions were found to be up-regulated in all three studies mainly playing roles related to phytohormone metabolism, catabolism and defense. To validate the function of identified candidate genes, we used the technique of virus-induced gene silencing (VIGS) to silence the expression of three putative N. attenuata genes: germin-like protein, indole-3-acetic acid-amido synthetase GH3.9 and, as a proof-of-principle, calcium and calmodulin-dependent protein kinase (CCaMK). The silencing of the three plant genes in roots was successful, but only CCaMK silencing had a significant effect on the interaction with R. irregularis. Interestingly, when a highly activated inoculum was used for plant inoculation, the effect of CCaMK silencing on fungal colonization was masked, probably due to trans-complementation. This study demonstrates that large

  15. Virus-Induced Gene Silencing Using Tobacco Rattle Virus as a Tool to Study the Interaction between Nicotiana attenuata and Rhizophagus irregularis.

    PubMed

    Groten, Karin; Pahari, Nabin T; Xu, Shuqing; Miloradovic van Doorn, Maja; Baldwin, Ian T

    2015-01-01

    Most land plants live in a symbiotic association with arbuscular mycorrhizal fungi (AMF) that belong to the phylum Glomeromycota. Although a number of plant genes involved in the plant-AMF interactions have been identified by analyzing mutants, the ability to rapidly manipulate gene expression to study the potential functions of new candidate genes remains unrealized. We analyzed changes in gene expression of wild tobacco roots (Nicotiana attenuata) after infection with mycorrhizal fungi (Rhizophagus irregularis) by serial analysis of gene expression (SuperSAGE) combined with next generation sequencing, and established a virus-induced gene-silencing protocol to study the function of candidate genes in the interaction. From 92,434 SuperSAGE Tag sequences, 32,808 (35%) matched with our in-house Nicotiana attenuata transcriptome database and 3,698 (4%) matched to Rhizophagus genes. In total, 11,194 Tags showed a significant change in expression (p<0.05, >2-fold change) after infection. When comparing the functions of highly up-regulated annotated Tags in this study with those of two previous large-scale gene expression studies, 18 gene functions were found to be up-regulated in all three studies mainly playing roles related to phytohormone metabolism, catabolism and defense. To validate the function of identified candidate genes, we used the technique of virus-induced gene silencing (VIGS) to silence the expression of three putative N. attenuata genes: germin-like protein, indole-3-acetic acid-amido synthetase GH3.9 and, as a proof-of-principle, calcium and calmodulin-dependent protein kinase (CCaMK). The silencing of the three plant genes in roots was successful, but only CCaMK silencing had a significant effect on the interaction with R. irregularis. Interestingly, when a highly activated inoculum was used for plant inoculation, the effect of CCaMK silencing on fungal colonization was masked, probably due to trans-complementation. This study demonstrates that large

  16. The IL-6 response to Chlamydia from primary reproductive epithelial cells is highly variable and may be involved in differential susceptibility to the immunopathological consequences of chlamydial infection

    PubMed Central

    2013-01-01

    Background Chlamydia trachomatis infection results in reproductive damage in some women. The process and factors involved in this immunopathology are not well understood. This study aimed to investigate the role of primary human cellular responses to chlamydial stress response proteases and chlamydial infection to further identify the immune processes involved in serious disease sequelae. Results Laboratory cell cultures and primary human reproductive epithelial cultures produced IL-6 in response to chlamydial stress response proteases (CtHtrA and CtTsp), UV inactivated Chlamydia, and live Chlamydia. The magnitude of the IL-6 response varied considerably (up to 1000 pg ml-1) across different primary human reproductive cultures. Thus different levels of IL-6 production by reproductive epithelia may be a determinant in disease outcome. Interestingly, co-culture models with either THP-1 cells or autologous primary human PBMC generally resulted in increased levels of IL-6, except in the case of live Chlamydia where the level of IL-6 was decreased compared to the epithelial cell culture only, suggesting this pathway may be able to be modulated by live Chlamydia. PBMC responses to the stress response proteases (CtTsp and CtHtrA) did not significantly vary for the different participant cohorts. Therefore, these proteases may possess conserved innate PAMPs. MAP kinases appeared to be involved in this IL-6 induction from human cells. Finally, we also demonstrated that IL-6 was induced by these proteins and Chlamydia from mouse primary reproductive cell cultures (BALB/C mice) and mouse laboratory cell models. Conclusions We have demonstrated that IL-6 may be a key factor for the chlamydial disease outcome in humans, given that primary human reproductive epithelial cell culture showed considerable variation in IL-6 response to Chlamydia or chlamydial proteins, and that the presence of live Chlamydia (but not UV killed) during co-culture resulted in a reduced IL-6 response

  17. Development of tobacco ringspot virus-based vectors for foreign gene expression and virus-induced gene silencing in a variety of plants.

    PubMed

    Zhao, Fumei; Lim, Seungmo; Igori, Davaajargal; Yoo, Ran Hee; Kwon, Suk-Yoon; Moon, Jae Sun

    2016-05-01

    We report here the development of tobacco ringspot virus (TRSV)-based vectors for the transient expression of foreign genes and for the analysis of endogenous gene function in plants using virus-induced gene silencing. The jellyfish green fluorescent protein (GFP) gene was inserted between the TRSV movement protein (MP) and coat protein (CP) regions, resulting in high in-frame expression of the RNA2-encoded viral polyprotein. GFP was released from the polyprotein via an N-terminal homologous MP-CP cleavage site and a C-terminal foot-and-mouth disease virus (FMDV) 2 A catalytic peptide in Nicotiana benthamiana. The VIGS target gene was introduced in the sense and antisense orientations into a SnaBI site, which was created by mutating the sequence following the CP stop codon. VIGS of phytoene desaturase (PDS) in N. benthamiana, Arabidopsis ecotype Col-0, cucurbits and legumes led to obvious photo-bleaching phenotypes. A significant reduction in PDS mRNA levels in silenced plants was confirmed by semi-quantitative RT-PCR. PMID:26950504

  18. pol-miR-731, a teleost miRNA upregulated by megalocytivirus, negatively regulates virus-induced type I interferon response, apoptosis, and cell cycle arrest.

    PubMed

    Zhang, Bao-Cun; Zhou, Ze-Jun; Sun, Li

    2016-01-01

    Megalocytivirus is a DNA virus that is highly infectious in a wide variety of marine and freshwater fish, including Japanese flounder (Paralichthys olivaceus), a flatfish that is farmed worldwide. However, the infection mechanism of megalocytivirus remains largely unknown. In this study, we investigated the function of a flounder microRNA, pol-miR-731, in virus-host interaction. We found that pol-miR-731 was induced in expression by megalocytivirus and promoted viral replication at the early infection stage. In vivo and in vitro studies revealed that pol-miR-731 (i) specifically suppresses the expression of interferon regulatory factor 7 (IRF7) and cellular tumor antigen p53 in a manner that depended on the integrity of the pol-miR-731 complementary sequences in the 3' untranslated regions of IRF7 and p53, (ii) disrupts megalocytivirus-induced Type I interferon response through IRF7, (iii) inhibits megalocytivirus-induced splenocyte apoptosis and cell cycle arrest through p53. Furthermore, overexpression of IRF7 and p53 abolished both the inhibitory effects of pol-miR-731 on these biological processes and its stimulatory effect on viral replication. These results disclosed a novel evasion mechanism of megalocytivirus mediated by a host miRNA. This study also provides the first evidence that a virus-induced host miRNA can facilitate viral infection by simultaneously suppressing several antiviral pathways. PMID:27311682

  19. Association between susceptibility to Theiler's virus-induced demyelination and T-cell receptor Jbeta1-Cbeta1 polymorphism rather than Vbeta deletion.

    PubMed Central

    Bahk, Y Y; Kappel, C A; Rasmussen, G; Kim, B S

    1997-01-01

    Theiler's murine encephalomyelitis virus (TMEV) induces demyelinating disease in susceptible mouse strains after intracerebral inoculation. The clinical symptoms and histopathology of the central nervous system appear to be similar to those of human multiple sclerosis (MS), and thus, this system provides an excellent infectious animal model for studying MS. The virus-induced demyelination is immune mediated, and the genes involved in the immune response such as those for the T-cell receptor beta-chain and major histocompatibility complex (MHC) haplotypes are known to influence disease susceptibility. To define whether the T-cell receptor Jbeta-Cbeta or Vbeta genes are associated with susceptibility, we have analyzed F2 mice from crosses of susceptible SJL/J (Vbeta(a)-JCbeta(b)) mice and resistant C57L (Vbeta(a)-JCbeta(a)) mice. Our results indicate that susceptibility to TMEV-induced demyelination is associated with restriction fragment length polymorphism reflecting the T-cell receptor Jbeta1-Cbeta1 region rather than the Vbeta polymorphism. This association becomes stronger when the MHC haplotype is considered in the linkage analysis. However, differences in the T-cell receptor alpha-chain haplotype have no significant influence on the pathogenesis of TMEV-induced demyelination. PMID:9094705

  20. A new mechanism of vitamin C effects on A/FM/1/47(H1N1) virus-induced pneumonia in restraint-stressed mice.

    PubMed

    Cai, Ying; Li, Yi-Fang; Tang, Lu-Ping; Tsoi, Bun; Chen, Min; Chen, Huan; Chen, Xiao-Mei; Tan, Rui-Rong; Kurihara, Hiroshi; He, Rong-Rong

    2015-01-01

    It is well known that vitamin C could protect against influenza infection, but little is known about the mechanisms. This study aimed to investigate the influence and possible mechanisms of vitamin C on pneumonia induced by influenza virus in stressed mice. Results showed that restraint stress significantly increased the mortality and the severity of pneumonia in mice caused by A/FM/1/47(H1N1) virus infection, which was attenuated by oral administration of vitamin C (125 and 250 mg/kg). Moreover, vitamin C administration significantly decreased expression of susceptibility genes, including mitochondrial antiviral signaling (MAVS) and interferon regulatory factor 3 (IRF3), and increased expression of NF-κB. These work in conjunction to induce type I interferons (IFNs) and elicit innate antiviral response as key factors in RIG-I-mediated signal transduction pathway. The above effects of vitamin C were further found to relate with inhibition of excess CORT synthesis by regulating steroid hydroxylating enzymes in adrenal gland. In conclusion, the protective effects of vitamin C on influenza virus-caused pneumonia might be related to its inhibition of CORT synthesis, which reduces the susceptibility to influenza viral infection in restraint-stressed mice. These findings provide a new mechanism for the effects of vitamin C on influenza virus-induced pneumonia in restraint-stressed mice. PMID:25710018

  1. Ubiquitin-specific Protease 15 Negatively Regulates Virus-induced Type I Interferon Signaling via Catalytically-dependent and -independent Mechanisms

    PubMed Central

    Zhang, Huan; Wang, Dang; Zhong, Huijuan; Luo, Rui; Shang, Min; Liu, Dezhi; Chen, Huanchun; Fang, Liurong; Xiao, Shaobo

    2015-01-01

    Viral infection triggers a series of signaling cascades, which converge to activate the transcription factors nuclear factor-κB (NF-κB) and interferon regulatory factor 3 (IRF3), thereby inducing the transcription of type I interferons (IFNs). Although not fully characterized, these innate antiviral responses are fine-tuned by dynamic ubiquitination and deubiquitination processes. In this study, we report ubiquitin-specific protease (USP) 15 is involved in regulation of the retinoic acid-inducible gene I (RIG-I)-dependent type I IFN induction pathway. Knockdown of endogenous USP15 augmented cellular antiviral responses. Overexpression of USP15 inhibited the transcription of IFN-β. Further analyses identified histidine 862 as a critical residue for USP15’s catalytic activity. Interestingly, USP15 specifically removed lysine 63-linked polyubiquitin chains from RIG-I among the essential components in RIG-I-like receptor-dependent pathway. In addition, we demonstrated that in contrast to USP15 de-ubiquitinating (DUB) activity, USP15-mediated inhibition of IFN signaling was not abolished by mutations eliminating the catalytic activity, indicating that a fraction of USP15-mediated IFN antagonism was independent of the DUB activity. Catalytically inactive USP15 mutants, as did the wild-type protein, disrupted virus-induced interaction of RIG-I and IFN-β promoter stimulator 1. Taken together, our data demonstrate that USP15 acts as a negative regulator of RIG-I signaling via DUB-dependent and independent mechanisms. PMID:26061460

  2. pol-miR-731, a teleost miRNA upregulated by megalocytivirus, negatively regulates virus-induced type I interferon response, apoptosis, and cell cycle arrest

    PubMed Central

    Zhang, Bao-cun; Zhou, Ze-jun; Sun, Li

    2016-01-01

    Megalocytivirus is a DNA virus that is highly infectious in a wide variety of marine and freshwater fish, including Japanese flounder (Paralichthys olivaceus), a flatfish that is farmed worldwide. However, the infection mechanism of megalocytivirus remains largely unknown. In this study, we investigated the function of a flounder microRNA, pol-miR-731, in virus-host interaction. We found that pol-miR-731 was induced in expression by megalocytivirus and promoted viral replication at the early infection stage. In vivo and in vitro studies revealed that pol-miR-731 (i) specifically suppresses the expression of interferon regulatory factor 7 (IRF7) and cellular tumor antigen p53 in a manner that depended on the integrity of the pol-miR-731 complementary sequences in the 3′ untranslated regions of IRF7 and p53, (ii) disrupts megalocytivirus-induced Type I interferon response through IRF7, (iii) inhibits megalocytivirus-induced splenocyte apoptosis and cell cycle arrest through p53. Furthermore, overexpression of IRF7 and p53 abolished both the inhibitory effects of pol-miR-731 on these biological processes and its stimulatory effect on viral replication. These results disclosed a novel evasion mechanism of megalocytivirus mediated by a host miRNA. This study also provides the first evidence that a virus-induced host miRNA can facilitate viral infection by simultaneously suppressing several antiviral pathways. PMID:27311682

  3. Virus-induced gene silencing of the RPC5-like subunit of RNA polymerase III caused pleiotropic effects in Nicotiana benthamiana.

    PubMed

    Nemchinov, Lev G; Boutanaev, Alexander M; Postnikova, Olga A

    2016-01-01

    In eukaryotic cells, RNA polymerase III is highly conserved and transcribes housekeeping genes such as ribosomal 5S rRNA, tRNA and other small RNAs. The RPC5-like subunit is one of the 17 subunits forming RNAPIII and its exact functional roles in the transcription are poorly understood. In this work, we report that virus-induced gene silencing of transcripts encoding a putative RPC5-like subunit of the RNA Polymerase III in a model species Nicotiana benthamiana had pleiotropic effects, including but not limited to severe dwarfing appearance, chlorosis, nearly complete reduction of internodes and abnormal leaf shape. Using transcriptomic analysis, we identified genes and pathways affected by RPC5 silencing and thus presumably related to the cellular roles of the subunit as well as to the downstream cascade of reactions in response to partial loss of RNA Polymerase III function. Our results suggest that silencing of the RPC5L in N. benthamiana disrupted not only functions commonly associated with the core RNA Polymerase III transcripts, but also more diverse cellular processes, including responses to stress. We believe this is the first demonstration that activity of the RPC5 subunit is critical for proper functionality of RNA Polymerase III and normal plant development. PMID:27282827

  4. Inflammatory and oncogenic roles of a tumor stem cell marker doublecortin-like kinase (DCLK1) in virus-induced chronic liver diseases.

    PubMed

    Ali, Naushad; Chandrakesan, Parthasarathy; Nguyen, Charles B; Husain, Sanam; Gillaspy, Allison F; Huycke, Mark; Berry, William L; May, Randal; Qu, Dongfeng; Weygant, Nathaniel; Sureban, Sripathi M; Bronze, Michael S; Dhanasekaran, Danny N; Houchen, Courtney W

    2015-08-21

    Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related mortality worldwide. We previously showed that a tumor/cancer stem cell (CSC) marker, doublecortin-like kinase (DCLK1) positively regulates hepatitis C virus (HCV) replication, and promotes tumor growth in colon and pancreas. Here, we employed transcriptome analysis, RNA interference, tumor xenografts, patient's liver tissues and hepatospheroids to investigate DCLK1-regulated inflammation and tumorigenesis in the liver. Our studies unveiled novel DCLK1-controlled feed-forward signaling cascades involving calprotectin subunit S100A9 and NFκB activation as a driver of inflammation. Validation of transcriptome data suggests that DCLK1 co-expression with HCV induces BRM/SMARCA2 of SW1/SNF1 chromatin remodeling complexes. Frequently observed lymphoid aggregates including hepatic epithelial and stromal cells of internodular septa extensively express DCLK1 and S100A9. The DCLK1 overexpression also correlates with increased levels of S100A9, c-Myc, and BRM levels in HCV/HBV-positive patients with cirrhosis and HCC. DCLK1 silencing inhibits S100A9 expression and hepatoma cell migration. Normal human hepatocytes (NHH)-derived spheroids exhibit CSC properties. These results provide new insights into the molecular mechanism of the hepatitis B/C-virus induced liver inflammation and tumorigenesis via DCLK1-controlled networks. Thus, DCLK1 appears to be a novel therapeutic target for the treatment of inflammatory diseases and HCC. PMID:25948779

  5. Tumor necrosis factor alpha is reparative via TNFR2 [corrected] in the hippocampus and via TNFR1 [corrected] in the striatum after virus-induced encephalitis.

    PubMed

    Rodriguez, Moses; Zoecklein, Laurie; Papke, Louisa; Gamez, Jeff; Denic, Aleksandar; Macura, Slobodan; Howe, Charles

    2009-01-01

    Differentiating between injurious and reparative factors facilitates appropriate therapeutic intervention. We evaluated the role of tumor necrosis factor alpha (TNFalpha) in parenchymal brain pathology resolution following virus-induced encephalitis from a picornavirus, Theiler's murine encephalomyelitis virus (TMEV). We infected the following animals with TMEV for 7 to 270 days: B6/129 TNF(-/-) mice (without TNFalpha expression), B6/129 TNFR1(-/-) mice (without TNFalpha receptor 1 expression), and B6/129 TNFR2(-/-) mice (without TNFalpha receptor 2 expression). Normal TNFalpha-expressing controls were TMEV-infected B6, 129/J, B6/129F1 and B6/129F2 mice. Whereas all strains developed inflammation and neuronal injury in the hippocampus and striatum 7 to 21 days postinfection (dpi), the control mice resolved the pathology by 45 to 90 dpi. However, parenchymal hippocampal and striatal injury persisted in B6/129 TNF(-/-) mice following infection. Treating virus-infected mice with active recombinant mouse TNFalpha resulted in less hippocampal and striatal pathology, whereas TNFalpha-neutralizing treatment worsened pathology. T1 "black holes" appeared on MRI during early infection in the hippocampus and striatum in all mice but persisted only in TNF(-/-) mice. TNFR2 [corrected] mediated hippocampal pathology resolution whereas TNFR1 [corrected] mediated striatal healing. These findings indicate the role of TNFalpha in resolution of sublethal hippocampal and striatal injury. PMID:18422761

  6. Virus-induced gene silencing identifies Catharanthus roseus 7-deoxyloganic acid-7-hydroxylase, a step in iridoid and monoterpene indole alkaloid biosynthesis.

    PubMed

    Salim, Vonny; Yu, Fang; Altarejos, Joaquín; De Luca, Vincenzo

    2013-12-01

    Iridoids are a major group of biologically active molecules that are present in thousands of plant species, and one versatile iridoid, secologanin, is a precursor for the assembly of thousands of monoterpenoid indole alkaloids (MIAs) as well as a number of quinoline alkaloids. This study uses bioinformatics to screen large databases of annotated transcripts from various MIA-producing plant species to select candidate genes that may be involved in iridoid biosynthesis. Virus-induced gene silencing of the selected genes combined with metabolite analyses of silenced plants was then used to identify the 7-deoxyloganic acid 7-hydroxylase (CrDL7H) that is involved in the 3rd to last step in secologanin biosynthesis. Silencing of CrDL7H reduced secologanin levels by at least 70%, and increased the levels of 7-deoxyloganic acid to over 4 mg g(-1) fresh leaf weight compared to control plants in which this iridoid is not detected. Functional expression of this CrDL7H in yeast confirmed its biochemical activity, and substrate specificity studies showed its preference for 7-deoxyloganic acid over other closely related substrates. Together, these results suggest that hydroxylation precedes carboxy-O-methylation in the secologanin pathway in Catharanthus roseus. PMID:24103035

  7. Virus-induced gene silencing of the RPC5-like subunit of RNA polymerase III caused pleiotropic effects in Nicotiana benthamiana

    PubMed Central

    Nemchinov, Lev G.; Boutanaev, Alexander M.; Postnikova, Olga A.

    2016-01-01

    In eukaryotic cells, RNA polymerase III is highly conserved and transcribes housekeeping genes such as ribosomal 5S rRNA, tRNA and other small RNAs. The RPC5-like subunit is one of the 17 subunits forming RNAPIII and its exact functional roles in the transcription are poorly understood. In this work, we report that virus-induced gene silencing of transcripts encoding a putative RPC5-like subunit of the RNA Polymerase III in a model species Nicotiana benthamiana had pleiotropic effects, including but not limited to severe dwarfing appearance, chlorosis, nearly complete reduction of internodes and abnormal leaf shape. Using transcriptomic analysis, we identified genes and pathways affected by RPC5 silencing and thus presumably related to the cellular roles of the subunit as well as to the downstream cascade of reactions in response to partial loss of RNA Polymerase III function. Our results suggest that silencing of the RPC5L in N. benthamiana disrupted not only functions commonly associated with the core RNA Polymerase III transcripts, but also more diverse cellular processes, including responses to stress. We believe this is the first demonstration that activity of the RPC5 subunit is critical for proper functionality of RNA Polymerase III and normal plant development. PMID:27282827

  8. Dissecting Functions of KATANIN and WRINKLED1 in Cotton Fiber Development by Virus-Induced Gene Silencing1[C][W][OA

    PubMed Central

    Qu, Jing; Ye, Jian; Geng, Yun-Feng; Sun, Yan-Wei; Gao, Shi-Qiang; Zhang, Bi-Pei; Chen, Wen; Chua, Nam-Hai

    2012-01-01

    Most of the world’s natural fiber comes from cotton (Gossypium spp.), which is an important crop worldwide. Characterizing genes that regulate cotton yield and fiber quality is expected to benefit the sustainable production of natural fiber. Although a huge number of expressed sequence tag sequences are now available in the public database, large-scale gene function analysis has been hampered by the low-efficiency process of generating transgenic cotton plants. Tobacco rattle virus (TRV) has recently been reported to trigger virus-induced gene silencing (VIGS) in cotton leaves. Here, we extended the utility of this method by showing that TRV-VIGS can operate in reproductive organs as well. We used this method to investigate the function of KATANIN and WRINKLED1 in cotton plant development. Cotton plants with suppressed KATANIN expression produced shorter fibers and elevated weight ratio of seed oil to endosperm. By contrast, silencing of WRINKLED1 expression resulted in increased fiber length but reduced oil seed content, suggesting the possibility to increase fiber length by repartitioning carbon flow. Our results provide evidence that the TRV-VIGS system can be used for rapid functional analysis of genes involved in cotton fiber development. PMID:22837356

  9. Remodeling the Endoplasmic Reticulum by Poliovirus Infection and by Individual Viral Proteins: an Autophagy-Like Origin for Virus-Induced Vesicles

    PubMed Central

    Suhy, David A.; Giddings, Thomas H.; Kirkegaard, Karla

    2000-01-01

    All positive-strand RNA viruses of eukaryotes studied assemble RNA replication complexes on the surfaces of cytoplasmic membranes. Infection of mammalian cells with poliovirus and other picornaviruses results in the accumulation of dramatically rearranged and vesiculated membranes. Poliovirus-induced membranes did not cofractionate with endoplasmic reticulum (ER), lysosomes, mitochondria, or the majority of Golgi-derived or endosomal membranes in buoyant density gradients, although changes in ionic strength affected ER and virus-induced vesicles, but not other cellular organelles, similarly. When expressed in isolation, two viral proteins of the poliovirus RNA replication complex, 3A and 2C, cofractionated with ER membranes. However, in cells that expressed 2BC, a proteolytic precursor of the 2B and 2C proteins, membranes identical in buoyant density to those observed during poliovirus infection were formed. When coexpressed with 2BC, viral protein 3A was quantitatively incorporated into these fractions, and the membranes formed were ultrastructurally similar to those in poliovirus-infected cells. These data argue that poliovirus-induced vesicles derive from the ER by the action of viral proteins 2BC and 3A by a mechanism that excludes resident host proteins. The double-membraned morphology, cytosolic content, and apparent ER origin of poliovirus-induced membranes are all consistent with an autophagic origin for these membranes. PMID:10982339

  10. β-Catenin Upregulates the Constitutive and Virus-Induced Transcriptional Capacity of the Interferon Beta Promoter through T-Cell Factor Binding Sites

    PubMed Central

    Marcato, Vasco; Luron, Lionel; Laqueuvre, Lucie M.; Simon, Dominique; Mansuroglu, Zeyni; Flamand, Marie; Panthier, Jean-Jacques; Souès, Sylvie; Massaad, Charbel

    2015-01-01

    Rapid upregulation of interferon beta (IFN-β) expression following virus infection is essential to set up an efficient innate antiviral response. Biological roles related to the antiviral and immune response have also been associated with the constitutive production of IFN-β in naive cells. However, the mechanisms capable of modulating constitutive IFN-β expression in the absence of infection remain largely unknown. In this work, we demonstrate that inhibition of the kinase glycogen synthase kinase 3 (GSK-3) leads to the upregulation of the constitutive level of IFN-β expression in noninfected cells, provided that GSK-3 inhibition is correlated with the binding of β-catenin to the IFN-β promoter. Under these conditions, IFN-β expression occurred through the T-cell factor (TCF) binding sites present on the IFN-β promoter independently of interferon regulatory factor 3 (IRF3). Enhancement of the constitutive level of IFN-β per se was able to confer an efficient antiviral state to naive cells and acted in synergy with virus infection to stimulate virus-induced IFN-β expression. Further emphasizing the role of β-catenin in the innate antiviral response, we show here that highly pathogenic Rift Valley fever virus (RVFV) targets the Wnt/β-catenin pathway and the formation of active TCF/β-catenin complexes at the transcriptional and protein level in RVFV-infected cells and mice. PMID:26459757

  11. Development of an Efficient Virus Induced Gene Silencing Strategy in the Non-Model Wild Ginger-Zingiber zerumbet and Investigation of Associated Proteome Changes

    PubMed Central

    Mahadevan, Chidambareswaren; Jaleel, Abdul; Deb, Lokesh; Thomas, George; Sakuntala, Manjula

    2015-01-01

    Zingiber zerumbet (Zingiberaceae) is a wild, tropical medicinal herb that shows a high degree of resistance to diseases affecting cultivated ginger. Barley stripe mosaic virus (BSMV) silencing vectors containing an endogenous phytoene desaturase (PDS) gene fragment were agroinfiltrated into young leaves of Z. zerumbet under controlled growth conditions to effect virus-induced gene silencing (VIGS). Infiltrated leaves as well as newly emerged leaves and tillers showed visual signs of PDS silencing after 30 days. Replication and systemic movement of the viral vectors in silenced plants were confirmed by RT-PCR. Real-time quantitative PCR analysis verified significant down-regulation of PDS transcripts in the silenced tissues. Label-free proteomic analysis was conducted in leaves with established PDS transcript down regulation and buffer-infiltrated (mock) leaves. A total of 474 proteins were obtained, which were up-regulated, down-regulated or modulated de novo during VIGS. Most of these proteins were localized to the chloroplast, as revealed by UniprotKB analysis, and among the up-regulated proteins there were abiotic stress responsive, photosynthetic, metabolic and membrane proteins. Moreover, the demonstration of viral proteins together with host proteins proved successful viral infection. We report for the first time the establishment of a high-throughput gene functional analysis platform using BSMV-mediated VIGS in Z. zerumbet, as well as proteomic changes associated with VIGS. PMID:25918840

  12. Characterization of the Rana grylio virus 3{beta}-hydroxysteroid dehydrogenase and its novel role in suppressing virus-induced cytopathic effect

    SciTech Connect

    Sun Wei; Huang Youhua; Zhao Zhe; Gui Jianfang; Zhang Qiya . E-mail: zhangqy@ihb.ac.cn

    2006-12-08

    The 3{beta}-hydroxysteroid dehydrogenase (3{beta}-HSD) isoenzymes play a key role in cellular steroid hormone synthesis. Here, a 3{beta}-HSD gene homolog was cloned from Rana grylio virus (RGV), a member of family Iridoviridae. RGV 3{beta}-HSD gene has 1068 bp, encoding a 355 aa predicted protein. Transcription analyses showed that RGV 3{beta}-HSD gene was transcribed immediate-early during infection from an initiation site 19 nucleotides upstream of the translation start site. Confocal microscopy revealed that the 3{beta}-HSD-EGFP fusion protein was exclusively colocalized with the mitochondria marker (pDsRed2-Mito) in EPC cells. Upon morphological observation and MTT assay, it was revealed that overexpression of RGV 3{beta}-HSD in EPC cells could apparently suppress RGV-induced cytopathic effect (CPE). The present studies indicate that the RGV immediate-early 3{beta}-HSD gene encodes a mitochondria-localized protein, which has a novel role in suppressing virus-induced CPE. All these suggest that RGV 3{beta}-HSD might be a protein involved in host-virus interaction.

  13. A New Mechanism of Vitamin C Effects on A/FM/1/47(H1N1) Virus-Induced Pneumonia in Restraint-Stressed Mice

    PubMed Central

    Cai, Ying; Li, Yi-Fang; Tang, Lu-Ping; Tsoi, Bun; Chen, Min; Chen, Huan; Chen, Xiao-Mei; Tan, Rui-Rong; Kurihara, Hiroshi; He, Rong-Rong

    2015-01-01

    It is well known that vitamin C could protect against influenza infection, but little is known about the mechanisms. This study aimed to investigate the influence and possible mechanisms of vitamin C on pneumonia induced by influenza virus in stressed mice. Results showed that restraint stress significantly increased the mortality and the severity of pneumonia in mice caused by A/FM/1/47(H1N1) virus infection, which was attenuated by oral administration of vitamin C (125 and 250 mg/kg). Moreover, vitamin C administration significantly decreased expression of susceptibility genes, including mitochondrial antiviral signaling (MAVS) and interferon regulatory factor 3 (IRF3), and increased expression of NF-κB. These work in conjunction to induce type I interferons (IFNs) and elicit innate antiviral response as key factors in RIG-I-mediated signal transduction pathway. The above effects of vitamin C were further found to relate with inhibition of excess CORT synthesis by regulating steroid hydroxylating enzymes in adrenal gland. In conclusion, the protective effects of vitamin C on influenza virus-caused pneumonia might be related to its inhibition of CORT synthesis, which reduces the susceptibility to influenza viral infection in restraint-stressed mice. These findings provide a new mechanism for the effects of vitamin C on influenza virus-induced pneumonia in restraint-stressed mice. PMID:25710018

  14. Aquaporin-mediated long-distance polyphosphate translocation directed towards the host in arbuscular mycorrhizal symbiosis: application of virus-induced gene silencing.

    PubMed

    Kikuchi, Yusuke; Hijikata, Nowaki; Ohtomo, Ryo; Handa, Yoshihiro; Kawaguchi, Masayoshi; Saito, Katsuharu; Masuta, Chikara; Ezawa, Tatsuhiro

    2016-09-01

    Arbuscular mycorrhizal fungi translocate polyphosphate through hyphae over a long distance to deliver to the host. More than three decades ago, suppression of host transpiration was found to decelerate phosphate delivery of the fungal symbiont, leading us to hypothesize that transpiration provides a primary driving force for polyphosphate translocation, probably via creating hyphal water flow in which fungal aquaporin(s) may be involved. The impact of transpiration suppression on polyphosphate translocation through hyphae of Rhizophagus clarus was evaluated. An aquaporin gene expressed in intraradical mycelia was characterized and knocked down by virus-induced gene silencing to investigate the involvement of the gene in polyphosphate translocation. Rhizophagus clarus aquaporin 3 (RcAQP3) that was most highly expressed in intraradical mycelia encodes an aquaglyceroporin responsible for water transport across the plasma membrane. Knockdown of RcAQP3 as well as the suppression of host transpiration decelerated polyphosphate translocation in proportion to the levels of knockdown and suppression, respectively. These results provide the first insight into the mechanism underlying long-distance polyphosphate translocation in mycorrhizal associations at the molecular level, in which host transpiration and the fungal aquaporin play key roles. A hypothetical model of the translocation is proposed for further elucidation of the mechanism. PMID:27136716

  15. Optimization of automated segmentation of monkeypox virus-induced lung lesions from normal lung CT images using hard C-means algorithm

    NASA Astrophysics Data System (ADS)

    Castro, Marcelo A.; Thomasson, David; Avila, Nilo A.; Hufton, Jennifer; Senseney, Justin; Johnson, Reed F.; Dyall, Julie

    2013-03-01

    Monkeypox virus is an emerging zoonotic pathogen that results in up to 10% mortality in humans. Knowledge of clinical manifestations and temporal progression of monkeypox disease is limited to data collected from rare outbreaks in remote regions of Central and West Africa. Clinical observations show that monkeypox infection resembles variola infection. Given the limited capability to study monkeypox disease in humans, characterization of the disease in animal models is required. A previous work focused on the identification of inflammatory patterns using PET/CT image modality in two non-human primates previously inoculated with the virus. In this work we extended techniques used in computer-aided detection of lung tumors to identify inflammatory lesions from monkeypox virus infection and their progression using CT images. Accurate estimation of partial volumes of lung lesions via segmentation is difficult because of poor discrimination between blood vessels, diseased regions, and outer structures. We used hard C-means algorithm in conjunction with landmark based registration to estimate the extent of monkeypox virus induced disease before inoculation and after disease progression. Automated estimation is in close agreement with manual segmentation.

  16. Enhancement by tumor necrosis factor alpha of dengue virus-induced endothelial cell production of reactive nitrogen and oxygen species is key to hemorrhage development.

    PubMed

    Yen, Yu-Ting; Chen, Hsuen-Chin; Chen, Hseun-Chin; Lin, Yang-Ding; Shieh, Chi-Chang; Wu-Hsieh, Betty A

    2008-12-01

    Hemorrhage is a severe manifestation of dengue disease. Virus strain and host immune response have been implicated as the risk factors for hemorrhage development. To delineate the complex interplay between the virus and the host, we established a dengue hemorrhage model in immune-competent mice. Mice inoculated intradermally with dengue virus develop hemorrhage within 3 days. In the present study, we showed by the presence of NS1 antigen and viral nuclei acid that dengue virus actively infects the endothelium at 12 h and 24 h after inoculation. Temporal studies showed that beginning at day 2, there was macrophage infiltration into the vicinity of the endothelium, increased tumor necrosis factor alpha (TNF-alpha) production, and endothelial cell apoptosis in the tissues. In the meantime, endothelial cells in the hemorrhage tissues expressed inducible nitric oxide synthase (iNOS) and nitrotyrosine. In vitro studies showed that primary mouse and human endothelial cells were productively infected by dengue virus. Infection by dengue virus induced endothelial cell production of reactive nitrogen and oxygen species and apoptotic cell death, which was greatly enhanced by TNF-alpha. N(G)-nitro-L-arginine methyl ester and N-acetyl cysteine reversed the effects of dengue virus and TNF-alpha on endothelial cells. Importantly, hemorrhage development and the severity of hemorrhage were greatly reduced in mice lacking iNOS or p47(phox) or treatment with oxidase inhibitor, pointing to the critical roles of reactive nitrogen and oxygen species in dengue hemorrhage. PMID:18842737

  17. Virus-induced gene silencing reveals control of reactive oxygen species accumulation and salt tolerance in tomato by γ-aminobutyric acid metabolic pathway.

    PubMed

    Bao, Hexigeduleng; Chen, Xianyang; Lv, Sulian; Jiang, Ping; Feng, Juanjuan; Fan, Pengxiang; Nie, Lingling; Li, Yinxin

    2015-03-01

    γ-Aminobutyric acid (GABA) accumulates in many plant species in response to environmental stress. However, the physiological function of GABA or its metabolic pathway (GABA shunt) in plants remains largely unclear. Here, the genes, including glutamate decarboxylases (SlGADs), GABA transaminases (SlGABA-Ts) and succinic semialdehyde dehydrogenase (SlSSADH), controlling three steps of the metabolic pathway of GABA, were studied through virus-induced gene silencing approach in tomato. Silencing of SlGADs (GABA biosynthetic genes) and SlGABA-Ts (GABA catabolic genes) led to increased accumulation of reactive oxygen species (ROS) as well as salt sensitivity under 200 mm NaCl treatment. Targeted quantitative analysis of metabolites revealed that GABA decreased and increased in the SlGADs- and SlGABA-Ts-silenced plants, respectively, whereas succinate (the final product of GABA metabolism) decreased in both silenced plants. Contrarily, SlSSADH-silenced plants, also defective in GABA degradation process, showed dwarf phenotype, curled leaves and enhanced accumulation of ROS in normal conditions, suggesting the involvement of a bypath for succinic semialdehyde catabolism to γ-hydroxybutyrate as reported previously in Arabidopsis, were less sensitive to salt stress. These results suggest that GABA shunt is involved in salt tolerance of tomato, probably by affecting the homeostasis of metabolites such as succinate and γ-hydroxybutyrate and subsequent ROS accumulation under salt stress. PMID:25074245

  18. Targeted activation of human Vγ9Vδ2-T cells controls epstein-barr virus-induced B cell lymphoproliferative disease.

    PubMed

    Xiang, Zheng; Liu, Yinping; Zheng, Jian; Liu, Ming; Lv, Aizhen; Gao, Yulong; Hu, Huaidong; Lam, Kowk-Tai; Chan, Godfrey Chi-Fung; Yang, Yuanzhong; Chen, Honglin; Tsao, George Sai-Wah; Bonneville, Marc; Lau, Yu-Lung; Tu, Wenwei

    2014-10-13

    Epstein-Barr virus-induced lymphoproliferative disease (EBV-LPD) after transplantation remains a serious and life-threatening complication. Herein we showed that the aminobisphosphonate pamidronate-expanded human Vγ9Vδ2-T cells efficiently killed EBV-transformed autologous lymphoblastoid B cell lines (EBV-LCL) through γ/δ-TCR and NKG2D receptor triggering and Fas and TRAIL engagement. By inoculation of EBV-LCL in Rag2(-/-)γc(-/-) mice and humanized mice, we established lethal EBV-LPD with characteristics close to those of the human disease. Adoptive transfer of pamidronate-expanded Vγ9Vδ2-T cells alone effectively prevented EBV-LPD in Rag2(-/-)γc(-/-) mice and induced EBV-LPD regression in EBV(+) tumor-bearing Rag2(-/-)γc(-/-) mice. Pamidronate treatment inhibited EBV-LPD development in humanized mice through selective activation and expansion of Vγ9Vδ2-T cells. This study provides proof-of-principle for a therapeutic approach using pamidronate to control EBV-LPD through Vγ9Vδ2-T cell targeting. PMID:25220446

  19. Tobacco mosaic virus 126-kDa protein increases the susceptibility of Nicotiana tabacum to other viruses and its dosage affects virus-induced gene silencing.

    PubMed

    Harries, Phillip A; Palanichelvam, Karuppaiah; Bhat, Sumana; Nelson, Richard S

    2008-12-01

    The Tobacco mosaic virus (TMV) 126-kDa protein is a suppressor of RNA silencing previously shown to delay the silencing of transgenes in Nicotiana tabacum and N. benthamiana. Here, we demonstrate that expression of a 126-kDa protein-green fluorescent protein (GFP) fusion (126-GFP) in N. tabacum increases susceptibility to a broad assortment of viruses, including Alfalfa mosaic virus, Brome mosaic virus, Tobacco rattle virus (TRV), and Potato virus X. Given its ability to enhance TRV infection in tobacco, we tested the effect of 126-GFP expression on TRV-mediated virus-induced gene silencing (VIGS) and demonstrate that this protein can enhance silencing phenotypes. To explain these results, we examined the poorly understood effect of suppressor dosage on the VIGS response and demonstrated that enhanced VIGS corresponds to the presence of low levels of suppressor protein. A mutant version of the 126-kDa protein, inhibited in its ability to suppress silencing, had a minimal effect on VIGS, suggesting that the suppressor activity of the 126-kDa protein is indeed responsible for the observed dosage effects. These findings illustrate the sensitivity of host plants to relatively small changes in suppressor dosage and have implications for those interested in enhancing silencing phenotypes in tobacco and other species through VIGS. PMID:18986250

  20. The Role of T Cell Immunoglobulin Mucin Domains 1 and 4 in a Herpes Simplex Virus-Induced Behçet's Disease Mouse Model

    PubMed Central

    Shim, Ju A.

    2013-01-01

    The T cell immunoglobulin mucin (TIM) proteins regulate T cell activation and tolerance. TIM-1 plays an important role in the regulation of immune responses and the development of autoimmune diseases. TIM-4 is a natural ligand of TIM-1, and the interaction of TIM-1 and TIM-4 is involved in the regulation of T helper (Th) cell responses and modulation of the Th1/Th2 cytokine balance. Behçet's disease (BD) is a chronic, multisystemic inflammatory disorder with arthritic, intestinal, mucocutaneous, ocular, vascular, and central nervous system involvement. Tim-1 expression was lower in a herpes simplex virus-induced BD mouse model compared to that in asymptomatic BD normal (BDN) mice. Tim-4 expression was higher in BD mice than that in BDN mice. In this study, we investigated the Tim expression in a BD mouse model with BD-like symptoms. Tim-1 and Tim-4 expression was regulated by an expression vector or siRNA injected into the BD mouse model. The Tim-1 vector injected into BD mice resulted in changes in BD-like symptoms and decreased the severity score. Treatment with Tim-4 siRNA also improved BD-like symptoms and decreased the severity score accompanied by upregulation of regulatory T cells. We showed that regulating Tim-1 or Tim-4 affected BD-like symptoms in mice. PMID:24453431

  1. Activation of the c-H-ras proto-oncogene by retrovirus insertion and chromosomal rearrangement in a Moloney leukemia virus-induced T-cell leukemia.

    PubMed Central

    Ihle, J N; Smith-White, B; Sisson, B; Parker, D; Blair, D G; Schultz, A; Kozak, C; Lunsford, R D; Askew, D; Weinstein, Y

    1989-01-01

    A rearrangement of the c-H-ras locus was detected in a T-cell line (DA-2) established from a Moloney leukemia virus-induced tumor. This rearrangement was associated with the high-level expression of H-ras RNA and the H-ras gene product, p21. DNA from DA-2 cells transformed fibroblasts in DNA transfection experiments, and the transformed fibroblasts contained the rearranged H-ras locus. The rearrangement involved one allele and was present in tissue from the primary tumor from which the cell line was isolated. Cloning and sequencing of the rearranged allele and comparison with the normal allele demonstrated that the rearrangement was complex and probably resulted from the integration of a retrovirus in the H-ras locus between a 5' noncoding exon and the first coding exon and a subsequent homologous recombination between this provirus and another newly acquired provirus also located on chromosome 7. These events resulted in the translocation of the coding exons of the H-ras locus away from the 5' noncoding exon region to a new genomic site on chromosome 7. Sequencing of the coding regions of the gene failed to detect mutations in the 12th, 13th, 59th, or 61st codons. The possible reasons for the complexity of the rearrangement and the significance of the activation of the H-ras locus to T-cell transformation are discussed. Images PMID:2542606

  2. Immunopathologic aspects of woodchuck hepatitis.

    PubMed Central

    Frommel, D.; Crevat, D.; Vitvitsky, L.; Pichoud, C.; Hantz, O.; Chevalier, M.; Grimaud, J. A.; Lindberg, J.; Trépo, C. G.

    1984-01-01

    The natural history of infection with woodchuck hepatitis virus (WHV) has been studied in a colony of 38 Marmota monax. Besides serologic assessment for WHV markers, light-microscopic findings of 61 liver biopsies were correlated with the results of immunofluorescence analysis for nucleocapsid (WHcAg) and surface (WHsAg) antigens. Twenty-four chronic WHsAg carriers all featured signs of continuous viral replication. Two major immunomorphologic patterns were observed in their livers: 1) portal hepatitis in which WHcAg accumulated in the cytoplasm and WHsAg was associated with the hepatocyte membrane and 2) periportal hepatitis in which WHcAg shifted toward nuclear localization and WHsAg became mostly intracytoplasmic. Progression from portal to periportal hepatitis, observed in 7 woodchucks, appeared to be induced by a partial recovery of specific immune reactivity to WHV, insufficient, however, to interrupt WHV replication. Deposits of WHsAg and immunoglobulins were present in the kidney and spleen of animals with severe hepatitis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:6324594

  3. Immunopathology in Taenia solium neurocysticercosis.

    PubMed

    Fleury, A; Cardenas, G; Adalid-Peralta, L; Fragoso, G; Sciutto, E

    2016-03-01

    Neurocysticercosis is a clinically and radiologically heterogeneous disease, ranging from asymptomatic infection to a severe, potentially fatal clinical picture. The intensity and extension of the parasite-elicited inflammatory reaction is a key factor for such variability. The main features of the inflammatory process found in the brain and in the peripheral blood of neurocysticercosis patients will be discussed in this review, and the factors involved in its modulation will be herein presented. PMID:26667781

  4. Immunopathology of experimental cutaneous leishmaniasis.

    PubMed Central

    Andrade, Z. A.; Reed, S. G.; Roters, S. B.; Sadigursky, M.

    1984-01-01

    Relatively susceptible BALB/c and relatively resistant A/J mice were infected subcutaneously in the right hind footpad with promastigotes of Leishmania mexicana amazonensis. A large localized lesion developed within 2 months after infection in the BALB/c mice, while A/J mice exhibited a small discrete fibrotic nodule. Sequential immunologic and histologic examination demonstrated that BALB/c mice developed a nodular foam-cell type of lesion and progressive depression of a delayed-type hypersensitivity (DTH) response to leishmania antigen, while the A/J mice had a mixed cellular fibrosing and encapsulating reaction and developed and maintained positive DTH responses to leishmania antigen. Anti-leishmania antibody responses were positive at similar levels in both strains. The lesions in BALB/c mice were found in bone marrow, tendon, skin appendages, and regional lymph nodes, with a tendency toward cutaneous metastases. Lesions in A/J mice remained localized. Fibrosis, focal fibrinoid necrosis, and lymphocytic and macrophagic infiltration were the outstanding features. Light and transmission electron microscopic studies indicated that no outstanding destruction of leishmanias seemed to occur within macrophages of either mouse strain. In the more resistant A/J mice, however, parasitized macrophages were frequently necrotic, and degenerating leishmanias were often seen free in the interstitial tissue. These observations help the interpretation of the histologic features, as well as the pathogenesis, of cutaneous and mucocutaneous leishmaniasis in man. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 PMID:6691411

  5. Antibody response is required for protection from Theiler's virus-induced encephalitis in C57BL/6 mice in the absence of CD8{sup +} T cells

    SciTech Connect

    Kang, B.-S.; Palma, Joann P.; Lyman, Michael A.; Dal Canto, Mauro; Kim, Byung S. . E-mail: bskim@northwestern.edu

    2005-09-15

    Intracerebral infection of susceptible mice with Theiler's murine encephalomyelitis virus (TMEV) induces immune-mediated demyelinating disease and this system serves as a relevant infectious model for human multiple sclerosis. It was previously shown that {beta}{sub 2}M-deficient C57BL/6 mice lacking functional CD8{sup +} T cells display increased viral persistence and enhanced susceptibility to TMEV-induced demyelination, and yet the majority of mice are free of clinical signs. To understand the mechanisms involved in this general resistance of C57BL/6 mice in the absence of CTL responses, mice ({mu}MT) deficient in the B-cell compartment lacking membrane IgM molecules were treated with anti-CD8 antibody and then infected with TMEV. Although little difference in the proliferative responses of peripheral T cells to UV-inactivated TMEV and the resistance to demyelinating disease was observed between virus-infected {mu}MT and control B6 mice, the levels of CD4{sup +} T cells were higher in the CNS of {mu}MT mice. However, after treatment with anti-CD8 antibody, 100% of the mice displayed clinical gray matter disease and prolonged viral persistence in {mu}MT mice, while only 10% of B6 mice showed clinical symptoms and very low viral persistence. Transfusion of sera from TMEV-infected B6 mice into anti-CD8 antibody-treated {mu}MT mice partially restored resistance to virus-induced encephalitis. These results indicate that the early anti-viral antibody response is also important in the protection from TMEV-induced encephalitis particularly in the absence of CD8{sup +} T cells.

  6. Virus-induced gene silencing of PEAM4 affects floral morphology by altering the expression pattern of PsSOC1a and PsPVP in pea.

    PubMed

    Chen, Zhe-Hao; Jia, Fei-Fei; Hu, Jiang-Qin; Pang, Ji-Liang; Xu, Lei; Wang, Li-Lin

    2014-01-15

    pea-MADS4 (PEAM4) regulates floral morphology in Pisum sativum L., however, its molecular mechanisms still remain unclear. Virus-induced gene silencing (VIGS) is a recently developed reverse genetic approach that facilities an easier and more rapid study of gene functions. In this study, the PEAM4 gene was effectively silenced by VIGS using a pea early browning virus (PEBV) in wild type pea JI992. The infected plants showed abnormal phenotypes, as the floral organs, especially the sepals and petals changed in both size and shape, which made the corolla less closed. The petals changed in morphology and internal symmetry with, the stamens reduced and carpel dehisced. Larger sepals and longer tendrils with small cauline leaves appeared, with some sepals turning into bracts, and secondary inflorescences with fused floral organs were formed, indicating a flower-to-inflorescence change. The infected plants also displayed a delayed and prolonged flowering time. The PEAM4-VIGS plants with altered floral morphology were similar to the pim (proliferating inflorescence meristem) mutant and also mimicked the phenotypes of ap1 mutants in Arabidopsis. The expression pattern of the homologous genes PsSOC1a and PsSVP, which were involved in flowering time and florescence morphological control downstream of PEAM4, were analyzed by real-time RT-PCR and mRNA in situ hybridization. PsSOC1a and PsSVP were ectopically expressed and enhanced in the floral meristems from PEAM4-silenced plants. Our data suggests that PEAM4 may have a similar molecular mechanism as AtAP1, which inhibits the expression of PsSOC1a and PsSVP in the floral meristem from the early stages of flower development. As such, in this way PEAM4 plays a crucial role in maintaining floral organ identity and flower development in pea. PMID:24331430

  7. Optimization of a Virus-Induced Gene Silencing System with Soybean yellow common mosaic virus for Gene Function Studies in Soybeans

    PubMed Central

    Kim, Kil Hyun; Lim, Seungmo; Kang, Yang Jae; Yoon, Min Young; Nam, Moon; Jun, Tae Hwan; Seo, Min-Jung; Baek, Seong-Bum; Lee, Jeom-Ho; Moon, Jung-Kyung; Lee, Suk-Ha; Lee, Su-Heon; Lim, Hyoun-Sub; Moon, Jae Sun; Park, Chang-Hwan

    2016-01-01

    Virus-induced gene silencing (VIGS) is an effective tool for the study of soybean gene function. Successful VIGS depends on the interaction between virus spread and plant growth, which can be influenced by environmental conditions. Recently, we developed a new VIGS system derived from the Soybean yellow common mosaic virus (SYCMV). Here, we investigated several environmental and developmental factors to improve the efficiency of a SYCMV-based VIGS system to optimize the functional analysis of the soybean. Following SYCMV: Glycine max-phytoene desaturase (GmPDS) infiltration, we investigated the effect of photoperiod, inoculation time, concentration of Agrobacterium inoculm, and growth temperature on VIGS efficiency. In addition, the relative expression of GmPDS between non-silenced and silenced plants was measured by qRT-PCR. We found that gene silencing efficiency was highest at a photoperiod of 16/8 h (light/dark) at a growth temperature of approximately 27°C following syringe infiltration to unrolled unifoliolate leaves in cotyledon stage with a final SYCMV:GmPDS optimal density (OD)600 of 2.0. Using this optimized protocol, we achieved high efficiency of GmPDS-silencing in various soybean germplasms including cultivated and wild soybeans. We also confirmed that VIGS occurred in the entire plant, including the root, stem, leaves, and flowers, and could transmit GmPDS to other soybean germplasms via mechanical inoculation. This optimized protocol using a SYCMV-based VIGS system in the soybean should provide a fast and effective method to elucidate gene functions and for use in large-scale screening experiments. PMID:27147931

  8. Integrated Clinical, Pathologic, Virologic, and Transcriptomic Analysis of H5N1 Influenza Virus-Induced Viral Pneumonia in the Rhesus Macaque

    PubMed Central

    Shinya, Kyoko; Gao, Yuwei; Cilloniz, Cristian; Suzuki, Yasuhiro; Fujie, Masahiro; Deng, Guohua; Zhu, Qiyun; Fan, Shufang; Makino, Akiko; Muramoto, Yukiko; Fukuyama, Satoshi; Tamura, Daisuke; Noda, Takeshi; Eisfeld, Amie J.; Katze, Michael G.

    2012-01-01

    Viral pneumonia has been frequently reported during early stages of influenza virus pandemics and in many human cases of highly pathogenic avian influenza (HPAI) H5N1 virus infection. To better understand the pathogenesis of this disease, we produced nonlethal viral pneumonia in rhesus macaques by using an HPAI H5N1 virus (A/Anhui/2/2005; referred to as Anhui/2). Infected macaques were monitored for 14 days, and tissue samples were collected at 6 time points for virologic, histopathologic, and transcriptomic analyses. Anhui/2 efficiently replicated in the lung from 12 h to 3 days postinfection (p.i.) and caused temporal but severe pneumonia that began to resolve by day 14. Lung transcriptional changes were first observed at 6 h, and increased expression of vascular permeability regulators and neutrophil chemoattractants correlated with increased serum leakage and neutrophil infiltration in situ. Additional inflammatory, antiviral, and apoptotic genes were upregulated from 12 h, concurrent with viral antigen detection and increasing immune cell populations. A shift toward upregulation of acquired immunity was apparent after day 6. Expression levels of established immune cell molecular markers revealed remarkable similarity with pathological findings, indicating early and robust neutrophil infiltration, a slight delay in macrophage accumulation, and abundant late populations of T lymphocytes. We also characterized the putative mechanisms regulating a unique, pneumonia-associated biphasic fever pattern. Thus, this study is the first to use a comprehensive and integrative approach to delineate specific molecular mechanisms regulating influenza virus-induced pneumonia in nonhuman primates, an important first step toward better management of human influenza virus disease. PMID:22491448

  9. Characterization of a Previously Unidentified Viral Protein in Porcine Circovirus Type 2-Infected Cells and Its Role in Virus-Induced Apoptosis

    PubMed Central

    Liu, Jue; Chen, Isabelle; Kwang, Jimmy

    2005-01-01

    Porcine circovirus type 2 (PCV2) is the causative agent of postweaning multisystemic wasting syndrome in pigs. In this study, transcription and translation of a novel viral gene (termed ORF3 here) was detected during productive infection of PCV2 in PK15 cells. The results of infection with ORF3-deficient PCV2 by site-directed mutagenesis indicated that the protein is not essential for viral replication. To investigate the underlying mechanism of cell death caused by replication of PCV2, apoptosis characterized by chromosomal condensation and fragmentation, formation of apoptotic bodies, and significant increase in hypodiploids were detected in infected cells. We further demonstrated that PCV2-induced apoptosis required the activation of caspase-8 but not caspase-9. The activation of caspase-8 results in the activation of caspase-3 as shown by an increase in the cleavage of the caspase substrate in the infected cells. To determine whether ORF3 protein could trigger apoptosis, ORF3 as well as ORF1 and ORF2 genes were transiently expressed in PK15 and Cos-7 cells for apoptotic activity assay. Transfection of cells with the ORF3 alone induced apoptosis using a pathway similar to that described in the context of viral infection. This is further confirmed by a significant decrease in apoptotic activity of infected cells in the absence of the ORF3 expression, suggesting that the protein plays a major role in the induction of virus-induced apoptosis. Altogether, these results indicate that ORF3 is a novel PCV2 protein that is not essential for viral replication in cultured cells but is involved in PCV2-induced apoptosis by activating caspase-8 and caspase-3 pathways. PMID:15956572

  10. Virus-induced gene silencing of Withania somnifera squalene synthase negatively regulates sterol and defence-related genes resulting in reduced withanolides and biotic stress tolerance.

    PubMed

    Singh, Anup Kumar; Dwivedi, Varun; Rai, Avanish; Pal, Shaifali; Reddy, Sajjalavarahalli Gangireddy Eswara; Rao, Dodaghatta Krishnarao Venkata; Shasany, Ajit Kumar; Nagegowda, Dinesh A

    2015-12-01

    Withania somnifera (L.) Dunal is an important Indian medicinal plant that produces withanolides, which are triterpenoid steroidal lactones having diverse biological activities. To enable fast and efficient functional characterization of genes in this slow-growing and difficult-to-transform plant, a virus-induced gene silencing (VIGS) was established by silencing phytoene desaturase (PDS) and squalene synthase (SQS). VIGS of the gene encoding SQS, which provides precursors for triterpenoids, resulted in significant reduction of squalene and withanolides, demonstrating its application in studying withanolides biosynthesis in W. somnifera leaves. A comprehensive analysis of gene expression and sterol pathway intermediates in WsSQS-vigs plants revealed transcriptional modulation with positive feedback regulation of mevalonate pathway genes, and negative feed-forward regulation of downstream sterol pathway genes including DWF1 (delta-24-sterol reductase) and CYP710A1 (C-22-sterol desaturase), resulting in significant reduction of sitosterol, campesterol and stigmasterol. However, there was little effect of SQS silencing on cholesterol, indicating the contribution of sitosterol, campesterol and stigmasterol, but not of cholesterol, towards withanolides formation. Branch-point oxidosqualene synthases in WsSQS-vigs plants exhibited differential regulation with reduced CAS (cycloartenol synthase) and cycloartenol, and induced BAS (β-amyrin synthase) and β-amyrin. Moreover, SQS silencing also led to the down-regulation of brassinosteroid-6-oxidase-2 (BR6OX2), pathogenesis-related (PR) and nonexpressor of PR (NPR) genes, resulting in reduced tolerance to bacterial and fungal infection as well as to insect feeding. Taken together, SQS silencing negatively regulated sterol and defence-related genes leading to reduced phytosterols, withanolides and biotic stress tolerance, thus implicating the application of VIGS for functional analysis of genes related to withanolides

  11. Optimization of a Virus-Induced Gene Silencing System with Soybean yellow common mosaic virus for Gene Function Studies in Soybeans.

    PubMed

    Kim, Kil Hyun; Lim, Seungmo; Kang, Yang Jae; Yoon, Min Young; Nam, Moon; Jun, Tae Hwan; Seo, Min-Jung; Baek, Seong-Bum; Lee, Jeom-Ho; Moon, Jung-Kyung; Lee, Suk-Ha; Lee, Su-Heon; Lim, Hyoun-Sub; Moon, Jae Sun; Park, Chang-Hwan

    2016-04-01

    Virus-induced gene silencing (VIGS) is an effective tool for the study of soybean gene function. Successful VIGS depends on the interaction between virus spread and plant growth, which can be influenced by environmental conditions. Recently, we developed a new VIGS system derived from the Soybean yellow common mosaic virus (SYCMV). Here, we investigated several environmental and developmental factors to improve the efficiency of a SYCMV-based VIGS system to optimize the functional analysis of the soybean. Following SYCMV: Glycine max-phytoene desaturase (GmPDS) infiltration, we investigated the effect of photoperiod, inoculation time, concentration of Agrobacterium inoculm, and growth temperature on VIGS efficiency. In addition, the relative expression of GmPDS between non-silenced and silenced plants was measured by qRT-PCR. We found that gene silencing efficiency was highest at a photoperiod of 16/8 h (light/dark) at a growth temperature of approximately 27°C following syringe infiltration to unrolled unifoliolate leaves in cotyledon stage with a final SYCMV:GmPDS optimal density (OD)600 of 2.0. Using this optimized protocol, we achieved high efficiency of GmPDS-silencing in various soybean germplasms including cultivated and wild soybeans. We also confirmed that VIGS occurred in the entire plant, including the root, stem, leaves, and flowers, and could transmit GmPDS to other soybean germplasms via mechanical inoculation. This optimized protocol using a SYCMV-based VIGS system in the soybean should provide a fast and effective method to elucidate gene functions and for use in large-scale screening experiments. PMID:27147931

  12. Molecular cloning and functional characterization of the lycopene ε-cyclase gene via virus-induced gene silencing and its expression pattern in Nicotiana tabacum.

    PubMed

    Shi, Yanmei; Wang, Ran; Luo, Zhaopeng; Jin, Lifeng; Liu, Pingping; Chen, Qiansi; Li, Zefeng; Li, Feng; Wei, Chunyang; Wu, Mingzhu; Wei, Pan; Xie, He; Qu, Lingbo; Lin, Fucheng; Yang, Jun

    2014-01-01

    Lycopene ε-cyclase (ε-LCY) is a key enzyme that catalyzes the synthesis of α-branch carotenoids through the cyclization of lycopene. Two cDNA molecules encoding ε-LCY (designated Ntε-LCY1 and Ntε-LCY2) were cloned from Nicotiana tabacum. Ntε-LCY1 and Ntε-LCY2 are encoded by two distinct genes with different evolutionary origins, one originating from the tobacco progenitor, Nicotiana sylvestris, and the other originating from Nicotiana tomentosiformis. The two coding regions are 97% identical at the nucleotide level and 95% identical at the amino acid level. Transcripts of Ntε-LCY were detectable in both vegetative and reproductive organs, with a relatively higher level of expression in leaves than in other tissues. Subcellular localization experiments using an Ntε-LCY1-GFP fusion protein demonstrated that mature Ntε-LCY1 protein is localized within the chloroplast in Bright Yellow 2 suspension cells. Under low-temperature and low-irradiation stress, Ntε-LCY transcript levels substantially increased relative to control plants. Tobacco rattle virus (TRV)-mediated silencing of ε-LCY in Nicotiana benthamiana resulted in an increase of β-branch carotenoids and a reduction in the levels of α-branch carotenoids. Meanwhile, transcripts of related genes in the carotenoid biosynthetic pathway observably increased, with the exception of β-OHase in the TRV-ε-lcy line. Suppression of ε-LCY expression was also found to alleviate photoinhibition of Potosystem II in virus-induced gene silencing (VIGS) plants under low-temperature and low-irradiation stress. Our results provide insight into the regulatory role of ε-LCY in plant carotenoid biosynthesis and suggest a role for ε-LCY in positively modulating low temperature stress responses. PMID:25153631

  13. Molecular Cloning and Functional Characterization of the Lycopene ε-Cyclase Gene via Virus-Induced Gene Silencing and Its Expression Pattern in Nicotiana tabacum

    PubMed Central

    Shi, Yanmei; Wang, Ran; Luo, Zhaopeng; Jin, Lifeng; Liu, Pingping; Chen, Qiansi; Li, Zefeng; Li, Feng; Wei, Chunyang; Wu, Mingzhu; Wei, Pan; Xie, He; Qu, Lingbo; Lin, Fucheng; Yang, Jun

    2014-01-01

    Lycopene ε-cyclase (ε-LCY) is a key enzyme that catalyzes the synthesis of α-branch carotenoids through the cyclization of lycopene. Two cDNA molecules encoding ε-LCY (designated Ntε-LCY1 and Ntε-LCY2) were cloned from Nicotiana tabacum. Ntε-LCY1 and Ntε-LCY2 are encoded by two distinct genes with different evolutionary origins, one originating from the tobacco progenitor, Nicotiana sylvestris, and the other originating from Nicotiana tomentosiformis. The two coding regions are 97% identical at the nucleotide level and 95% identical at the amino acid level. Transcripts of Ntε-LCY were detectable in both vegetative and reproductive organs, with a relatively higher level of expression in leaves than in other tissues. Subcellular localization experiments using an Ntε-LCY1-GFP fusion protein demonstrated that mature Ntε-LCY1 protein is localized within the chloroplast in Bright Yellow 2 suspension cells. Under low-temperature and low-irradiation stress, Ntε-LCY transcript levels substantially increased relative to control plants. Tobacco rattle virus (TRV)-mediated silencing of ε-LCY in Nicotiana benthamiana resulted in an increase of β-branch carotenoids and a reduction in the levels of α-branch carotenoids. Meanwhile, transcripts of related genes in the carotenoid biosynthetic pathway observably increased, with the exception of β-OHase in the TRV-ε-lcy line. Suppression of ε-LCY expression was also found to alleviate photoinhibition of Potosystem II in virus-induced gene silencing (VIGS) plants under low-temperature and low-irradiation stress. Our results provide insight into the regulatory role of ε-LCY in plant carotenoid biosynthesis and suggest a role for ε-LCY in positively modulating low temperature stress responses. PMID:25153631

  14. Myxoma virus induces type I interferon production in murine plasmacytoid dendritic cells via a TLR9/MyD88-, IRF5/IRF7-, and IFNAR-dependent pathway.

    PubMed

    Dai, Peihong; Cao, Hua; Merghoub, Taha; Avogadri, Francesca; Wang, Weiyi; Parikh, Tanvi; Fang, Chee-Mun; Pitha, Paula M; Fitzgerald, Katherine A; Rahman, Masmudur M; McFadden, Grant; Hu, Xiaoyu; Houghton, Alan N; Shuman, Stewart; Deng, Liang

    2011-10-01

    Poxviruses are large DNA viruses that replicate in the cytoplasm of infected cells. Myxoma virus is a rabbit poxvirus that belongs to the Leporipoxvirus genus. It causes a lethal disease called myxomatosis in European rabbits but cannot sustain any detectable infection in nonlagomorphs. Vaccinia virus is a prototypal orthopoxvirus that was used as a vaccine to eradicate smallpox. Myxoma virus is nonpathogenic in mice, whereas systemic infection with vaccinia virus can be lethal even in immunocompetent mice. Plasmacytoid dendritic cells (pDCs) are potent type I interferon (IFN)-producing cells that play important roles in antiviral innate immunity. How poxviruses are sensed by pDCs to induce type I IFN production is not well understood. Here we report that infection of primary murine pDCs with myxoma virus, but not with vaccinia virus, induces IFN-α, IFN-β, tumor necrosis factor (TNF), and interleukin-12p70 (IL-12p70) production. Using pDCs derived from genetic knockout mice, we show that the myxoma virus-induced innate immune response requires the endosomal DNA sensor TLR9 and its adaptor MyD88, transcription factors IRF5 and IRF7, and the type I IFN positive-feedback loop mediated by IFNAR1. It is independent of the cytoplasmic RNA sensing pathway mediated by the mitochondrial adaptor molecule MAVS, the TLR3 adaptor TRIF, or the transcription factor IRF3. Using pharmacological inhibitors, we demonstrate that myxoma virus-induced type I IFN and IL-12p70 production in murine pDCs is also dependent on phosphatidylinositol 3-kinase (PI3K) and Akt. Furthermore, our results reveal that the N-terminal Z-DNA/RNA binding domain of vaccinia virulence factor E3, which is missing in the orthologous M029 protein expressed by myxoma virus, plays an inhibitory role in poxvirus sensing and innate cytokine production by murine pDCs. PMID:21835795

  15. Virus-induced gene-silencing in wheat spikes and grains and its application in functional analysis of HMW-GS-encoding genes

    PubMed Central

    2012-01-01

    Background The Barley stripe mosaic virus (BSMV)-based vector has been developed and used for gene silencing in barley and wheat seedlings to assess gene functions in pathogen- or insect-resistance, but conditions for gene silencing in spikes and grains have not been evaluated. In this study, we explored the feasibility of using BSMV for gene silencing in wheat spikes or grains. Results Apparent photobleaching on the spikes infected with BSMV:PDS at heading stage was observed after13 days post inoculation (dpi), and persisted until 30dpi, while the spikes inoculated with BSMV:00 remained green during the same period. Grains of BSMV:PDS infected spikes also exhibited photobleaching. Molecular analysis indicated that photobleached spikes or grains resulted from the reduction of endogenous PDS transcript abundances, suggesting that BSMV:PDS was able to induce PDS silencing in wheat spikes and grains. Inoculation onto wheat spikes from heading to flowering stage was optimal for efficient silencing of PDS in wheat spikes. Furthermore, we used the BSMV-based system to reduce the transcript level of 1Bx14, a gene encoding for High-molecular-weight glutenin subunit 1Bx14 (HMW-GS 1Bx14), by 97 % in the grains of the BSMV:1Bx14 infected spikes at 15dpi, compared with that in BSMV:00 infected spikes, and the reduction persisted until at least 25 dpi. The amount of the HMW-GS 1Bx14 was also detectably decreased. The percentage of glutenin macropolymeric proteins in total proteins was significantly reduced in the grains of 1Bx14-silenced plants as compared with that in the grains of BSMV:00 infected control plants, indicating that HMW-GS 1Bx14 is one of major components participating in the formation of glutenin macropolymers in wheat grains. Conclusion This is one of the first reports of successful application of BSMV-based virus-induced-gene-silencing (VIGS) for gene knockdown in wheat spikes and grains and its application in functional analysis of the 1Bx14 gene. The

  16. Tomato Infection by Whitefly-Transmitted Circulative and Non-Circulative Viruses Induce Contrasting Changes in Plant Volatiles and Vector Behaviour.

    PubMed

    Fereres, Alberto; Peñaflor, Maria Fernanda G V; Favaro, Carla F; Azevedo, Kamila E X; Landi, Carolina H; Maluta, Nathalie K P; Bento, José Mauricio S; Lopes, Joao R S

    2016-01-01

    , this type of virus-induced manipulation of vector behaviour was not observed for the semi persistent crinivirus, ToCV, which is not specifically transmitted by B. tabaci and has a much less intimate virus-vector relationship. PMID:27529271

  17. Replication and Virus-Induced Transcriptome of HAdV-5 in Normal Host Cells versus Cancer Cells - Differences of Relevance for Adenoviral Oncolysis

    PubMed Central

    Fellenberg, Kurt; Kaufmann, Johanna K.; Engelhardt, Sarah; Hoheisel, Jörg D.; Nettelbeck, Dirk M.

    2011-01-01

    Adenoviruses (Ads), especially HAdV-5, have been genetically equipped with tumor-restricted replication potential to enable applications in oncolytic cancer therapy. Such oncolytic adenoviruses have been well tolerated in cancer patients, but their anti-tumor efficacy needs to be enhanced. In this regard, it should be considered that cancer cells, dependent on their tissue of origin, can differ substantially from the normal host cells to which Ads are adapted by complex virus-host interactions. Consequently, viral replication efficiency, a key determinant of oncolytic activity, might be suboptimal in cancer cells. Therefore, we have analyzed both the replication kinetics of HAdV-5 and the virus-induced transcriptome in human bronchial epithelial cells (HBEC) in comparison to cancer cells. This is the first report on genome-wide expression profiling of Ads in their native host cells. We found that E1A expression and onset of viral genome replication are most rapid in HBEC and considerably delayed in melanoma cells. In squamous cell lung carcinoma cells, we observed intermediate HAdV-5 replication kinetics. Infectious particle production, viral spread and lytic activity of HAdV-5 were attenuated in melanoma cells versus HBEC. Expression profiling at the onset of viral genome replication revealed that HAdV-5 induced the strongest changes in the cellular transcriptome in HBEC, followed by lung cancer and melanoma cells. We identified prominent regulation of genes involved in cell cycle and DNA metabolism, replication and packaging in HBEC, which is in accord with the necessity to induce S phase for viral replication. Strikingly, in melanoma cells HAdV-5 triggered opposing regulation of said genes and, in contrast to lung cancer cells, no weak S phase induction was detected when using the E2F promoter as reporter. Our results provide a rationale for improving oncolytic adenoviruses either by adaptation of viral infection to target tumor cells or by modulating tumor cell

  18. Tomato Infection by Whitefly-Transmitted Circulative and Non-Circulative Viruses Induce Contrasting Changes in Plant Volatiles and Vector Behaviour

    PubMed Central

    Fereres, Alberto; Peñaflor, Maria Fernanda G. V.; Favaro, Carla F.; Azevedo, Kamila E. X.; Landi, Carolina H.; Maluta, Nathalie K. P.; Bento, José Mauricio S.; Lopes, Joao R.S.

    2016-01-01

    , this type of virus-induced manipulation of vector behaviour was not observed for the semi persistent crinivirus, ToCV, which is not specifically transmitted by B. tabaci and has a much less intimate virus-vector relationship. PMID:27529271

  19. Transcriptome Profiling of the Virus-Induced Innate Immune Response in Pteropus vampyrus and Its Attenuation by Nipah Virus Interferon Antagonist Functions

    PubMed Central

    Glennon, Nicole B.; Jabado, Omar; Lo, Michael K.

    2015-01-01

    ABSTRACT Bats are important reservoirs for several viruses, many of which cause lethal infections in humans but have reduced pathogenicity in bats. As the innate immune response is critical for controlling viruses, the nature of this response in bats and how it may differ from that in other mammals are of great interest. Using next-generation transcriptome sequencing (mRNA-seq), we profiled the transcriptional response of Pteropus vampyrus bat kidney (PVK) cells to Newcastle disease virus (NDV), an avian paramyxovirus known to elicit a strong innate immune response in mammalian cells. The Pteropus genus is a known reservoir of Nipah virus (NiV) and Hendra virus (HeV). Analysis of the 200 to 300 regulated genes showed that genes for interferon (IFN) and antiviral pathways are highly upregulated in NDV-infected PVK cells, including genes for beta IFN, RIG-I, MDA5, ISG15, and IRF1. NDV-infected cells also upregulated several genes not previously characterized to be antiviral, such as RND1, SERTAD1, CHAC1, and MORC3. In fact, we show that MORC3 is induced by both IFN and NDV infection in PVK cells but is not induced by either stimulus in human A549 cells. In contrast to NDV infection, HeV and NiV infection of PVK cells failed to induce these innate immune response genes. Likewise, an attenuated response was observed in PVK cells infected with recombinant NDVs expressing the NiV IFN antagonist proteins V and W. This study provides the first global profile of a robust virus-induced innate immune response in bats and indicates that henipavirus IFN antagonist mechanisms are likely active in bat cells. IMPORTANCE Bats are the reservoir host for many highly pathogenic human viruses, including henipaviruses, lyssaviruses, severe acute respiratory syndrome coronavirus, and filoviruses, and many other viruses have also been isolated from bats. Viral infections are reportedly asymptomatic or heavily attenuated in bat populations. Despite their ecological importance to viral

  20. vig-1, a New Fish Gene Induced by the Rhabdovirus Glycoprotein, Has a Virus-Induced Homologue in Humans and Shares Conserved Motifs with the MoaA Family

    PubMed Central

    Boudinot, Pierre; Massin, Pascale; Blanco, Mar; Riffault, Sabine; Benmansour, Abdenour

    1999-01-01

    We used mRNA differential display methodology to analyze the shift of transcription profile induced by the fish rhabdovirus, viral hemorrhagic septicemia virus (VHSV), in rainbow trout leukocytes. We identified and characterized a new gene which is directly induced by VHSV. This VHSV-induced gene (vig-1) encodes a 348-amino-acid protein. vig-1 is highly expressed during the experimental disease in lymphoid organs of the infected fish. Intramuscular injection of a plasmid vector expressing the viral glycoprotein results in vig-1 expression, showing that the external virus protein is sufficient for the induction. vig-1 expression is also obtained by a rainbow trout interferon-like factor, indicating that vig-1 can be induced through different pathways. Moreover, vig-1 is homologous to a recently described human cytomegalovirus-induced gene. Accordingly, vig-1 activation may represent a new virus-induced activation pathway highly conserved in vertebrates. The deduced amino acid sequence of vig-1 is significantly related to sequences required for the biosynthesis of metal cofactors. This suggests that the function of vig-1 may be involved in the nonspecific virus-induced synthesis of enzymatic cofactors of the nitric oxide pathway. PMID:9971762

  1. Respiratory Syncytial Virus-Inducible BCL-3 Expression Antagonizes the STAT/IRF and NF-κB Signaling Pathways by Inducing Histone Deacetylase 1 Recruitment to the Interleukin-8 Promoter

    PubMed Central

    Jamaluddin, Mohammad; Choudhary, Sanjeev; Wang, Shaofei; Casola, Antonella; Huda, Ruksana; Garofalo, Roberto P.; Ray, Sutapa; Brasier, Allan R.

    2005-01-01

    Respiratory syncytial virus (RSV) is a paramyxovirus that produces airway inflammation, in part by inducing interleukin-8 (IL-8) expression, a CXC-type chemokine, via the NF-κB/RelA and STAT/IRF signaling pathways. In RSV-infected A549 cells, IL-8 transcription attenuates after 24 h in spite of ongoing viral replication and persistence of nuclear RelA, suggesting a mechanism for transcriptional attenuation. RSV infection induces B-cell lymphoma protein -3 (Bcl-3) expression 6 to 12 h after viral infection, at times when IL-8 transcription is inhibited. By contrast, 293 cells, deficient in inducible Bcl-3 expression, show no attenuation of IL-8 transcription. We therefore examined Bcl-3's role in terminating virus-inducible IL-8 transcription. Transient expression of Bcl-3 potently inhibited virus-inducible IL-8 transcription by disrupting both the NF-κB and STAT/IRF pathways. Although previously Bcl-3 was thought to capture 50-kDa NF-κB1 isoforms in the cytoplasm, immunoprecipitation (IP) and electrophoretic mobility shift assays indicate that nuclear Bcl-3 associates with NF-κB1 without affecting DNA binding. Additionally, Bcl-3 potently inhibited the STAT/IRF pathway. Nondenaturing co-IP assays indicate that nuclear Bcl-3 associates with STAT-1 and histone deacetylase 1 (HDAC-1), increasing HDAC-1 recruitment to the IL-8 promoter. Treatment with the HDAC inhibitor trichostatin A blocks attenuation of IL-8 transcription. A nuclear targeting-deficient Bcl-3 is unable to enhance HDAC-1-mediated chemokine repression. Finally, small inhibitory RNA-mediated Bcl-3 “knockdown” resulted in enhanced RSV-induced chemokine expression in A549 cells. These data indicate that Bcl-3 is a virus-inducible inhibitor of chemokine transcription by interfering with the NF-κB and STAT/IRF signaling pathways by complexing with them and recruiting HDAC-1 to attenuate target promoter activity. PMID:16306601

  2. A novel p38 mitogen activated protein kinase (MAPK) specific inhibitor suppresses respiratory syncytial virus and influenza A virus replication by inhibiting virus-induced p38 MAPK activation.

    PubMed

    Choi, Myung-Soo; Heo, Jinyuk; Yi, Chae-Min; Ban, Junsu; Lee, Noh-Jin; Lee, Na-Rae; Kim, Sang Won; Kim, Nam-Jung; Inn, Kyung-Soo

    2016-08-26

    Respiratory syncytial virus (RSV) and influenza A virus are leading causes of acute lower respiratory infectious disease. Respiratory diseases caused by RSV and influenza A virus result in serious economic burden and life-threatening disease for immunocompromised people. With the revelation that p38 mitogen-activated protein kinase (MAPK) activity in host cells is crucial for infection and replication of RSV and influenza A virus, inhibition of p38 MAPK activity has been suggested as a potential antiviral therapeutic strategy. However, the low selectivity and high toxicity of the p38 MAPK inhibitors necessitate the development of better inhibitors. Herein, we report the synthesis of a novel p38 MAPK inhibitor, NJK14047, with high kinase selectivity. In this work, it was demonstrated that NJK14047 inhibits RSV- and influenza A-mediated p38 MAPK activation in epithelial cells. Subsequently, NJK14047 treatment resulted in decreased viral replication and viral mRNA synthesis. In addition, secretion of interleukin-6 from infected cells was greatly diminished by NJK14047, suggesting that it can ameliorate immunopathological responses to RSV and influenza A. Collectively, the results suggest that NJK14047 has therapeutic potential to treat respiratory viral infection through the suppression of p38 MAPK activation, which is suggested to be an essential step for respiratory virus infection. PMID:27346133

  3. Respiratory synctial virus infection in BALB/c mice previously immunized with formalin-inactivated virus induces enhanced pulmonary inflammatory response with a predominant Th2-like cytokine pattern.

    PubMed Central

    Waris, M E; Tsou, C; Erdman, D D; Zaki, S R; Anderson, L J

    1996-01-01

    Vaccination with formalin-inactivated respiratory syncytial virus (FI-RSV) caused excessive disease in infants upon subsequent natural infection with RSV. Recent studies with BALB/c mice have suggested that T cells are important contributors to lung immunopathology during RSV infection. In this study, we investigated vaccine-induced enhanced disease by immunizing BALB/c mice with live RSV intranasally or with FI-RSV intramuscularly. The mice were challenged with RSV 6 weeks later, and the pulmonary inflammatory response was studied by analyzing cells obtained by bronchoalveolar lavage 4 and 8 days after challenge. FI-RSV-immunized mice had an increased number of total cells, granulocytes, eosinophils, and CD4+ cells but a decreased number of CD8+ cells. The immunized mice also had a marked increase in the expression of mRNA for the Th2-type cytokines interleukin-5 (IL-5) and IL-13 as well as some increase in the expression of IL-10 (a Th2-type cytokine) mRNA and some decrease in the expression of IL-12 (a Th1-type cytokine) mRNA. The clear difference in the pulmonary inflammatory response to RSV between FI-RSV- and live-RSV-immunized mice suggests that this model can be used to evaluate the disease-enhancing potential of candidate RSV vaccines and better understand enhanced disease. PMID:8627759

  4. Epstein-Barr Virus-Induced Gene 3 (EBI3) Blocking Leads to Induce Antitumor Cytotoxic T Lymphocyte Response and Suppress Tumor Growth in Colorectal Cancer by Bidirectional Reciprocal-Regulation STAT3 Signaling Pathway

    PubMed Central

    Liang, Yanfang; Chen, Qianqian; Du, Wenjing; Chen, Can; Li, Feifei; Yang, Jingying; Peng, Jianyu; Kang, Dongping; Lin, Bihua; Chai, Xingxing; Zhou, Keyuan; Zeng, Jincheng

    2016-01-01

    Epstein-Barr virus-induced gene 3 (EBI3) is a member of the interleukin-12 (IL-12) family structural subunit and can form a heterodimer with IL-27p28 and IL-12p35 subunit to build IL-27 and IL-35, respectively. However, IL-27 stimulates whereas IL-35 inhibits antitumor T cell responses. To date, little is known about the role of EBI3 in tumor microenvironment. In this study, firstly we assessed EBI3, IL-27p28, IL-12p35, gp130, and p-STAT3 expression with clinicopathological parameters of colorectal cancer (CRC) tissues; then we evaluated the antitumor T cell responses and tumor growth with a EBI3 blocking peptide. We found that elevated EBI3 may be associated with IL-12p35, gp130, and p-STAT3 to promote CRC progression. EBI3 blocking peptide promoted antitumor cytotoxic T lymphocyte (CTL) response by inducing Granzyme B, IFN-γ production, and p-STAT3 expression and inhibited CRC cell proliferation and tumor growth to associate with suppressing gp130 and p-STAT3 expression. Taken together, these results suggest that EBI3 may mediate a bidirectional reciprocal-regulation STAT3 signaling pathway to assist the tumor escape immune surveillance in CRC. PMID:27247488

  5. Down-regulation of osmotin (PR5) gene by virus-induced gene silencing (VIGS) leads to susceptibility of resistant Piper colubrinum Link. to the oomycete pathogen Phytophthora capsici Leonian.

    PubMed

    Anu, K; Jessymol, K K; Chidambareswaren, M; Gayathri, G S; Manjula, S

    2015-06-01

    Piper colubrinum Link., a distant relative of Piper nigrum L., is immune to the oomycete pathogen Phytophthora capsici Leonian that causes 'quick wilt' in cultivated black pepper (P. nigrum). The osmotin, PR5 gene homologue, earlier identified from P. colubrinum, showed significant overexpression in response to pathogen and defense signalling molecules. The present study focuses on the functional validation of P. colubrinum osmotin (PcOSM) by virus induced gene silencing (VIGS) using Tobacco Rattle Virus (TRV)-based vector. P. colubrinum plants maintained under controlled growth conditions in a growth chamber were infiltrated with Agrobacterium carrying TRV empty vector (control) and TRV vector carrying PcOSM. Three weeks post infiltration, viral movement was confirmed in newly emerged leaves of infiltrated plants by RT-PCR using TRV RNA1 and TRV RNA2 primers. Semi-quantitative RT-PCR confirmed significant down-regulation of PcOSM gene in TRV-PcOSM infiltrated plant compared with the control plants. The control and silenced plants were challenged with Phytophthora capsici which demonstrated that knock-down of PcOSM in P. colubrinum leads to increased fungal mycelial growth in silenced plants compared to control plants, which was accompanied by decreased accumulation of H2O2 as indicated by 3,3'-diaminobenzidine (DAB) staining. Thus, in this study, we demonstrated that Piper colubrinum osmotin gene is required for resisting P. capsici infection and has possible role in hypersensitive cell death response and oxidative burst signaling during infection. PMID:26155671

  6. 9 CFR 113.42 - Detection of lymphocytic choriomeningitis contamination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... of at least 10 mice obtained from a source free of LCM shall be injected in the footpad of a hindfoot with 0.02 ml of the material being tested and observed each day for 21 days. (b) If any of the...

  7. 9 CFR 113.42 - Detection of lymphocytic choriomeningitis contamination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... of at least 10 mice obtained from a source free of LCM shall be injected in the footpad of a hindfoot with 0.02 ml of the material being tested and observed each day for 21 days. (b) If any of the...

  8. 9 CFR 113.42 - Detection of lymphocytic choriomeningitis contamination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... of at least 10 mice obtained from a source free of LCM shall be injected in the footpad of a hindfoot with 0.02 ml of the material being tested and observed each day for 21 days. (b) If any of the...

  9. 9 CFR 113.42 - Detection of lymphocytic choriomeningitis contamination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... of at least 10 mice obtained from a source free of LCM shall be injected in the footpad of a hindfoot with 0.02 ml of the material being tested and observed each day for 21 days. (b) If any of the...

  10. 9 CFR 113.42 - Detection of lymphocytic choriomeningitis contamination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... of at least 10 mice obtained from a source free of LCM shall be injected in the footpad of a hindfoot with 0.02 ml of the material being tested and observed each day for 21 days. (b) If any of the...

  11. Chagas disease cardiomyopathy: immunopathology and genetics.

    PubMed

    Cunha-Neto, Edecio; Chevillard, Christophe

    2014-01-01

    Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America and affects ca. 10 million people worldwide. About 30% of Chagas disease patients develop chronic Chagas disease cardiomyopathy (CCC), a particularly lethal inflammatory cardiomyopathy that occurs decades after the initial infection, while most patients remain asymptomatic. Mortality rate is higher than that of noninflammatory cardiomyopathy. CCC heart lesions present a Th1 T-cell-rich myocarditis, with cardiomyocyte hypertrophy and prominent fibrosis. Data suggest that the myocarditis plays a major pathogenetic role in disease progression. Major unmet goals include the thorough understanding of disease pathogenesis and therapeutic targets and identification of prognostic genetic factors. Chagas disease thus remains a neglected disease, with no vaccines or antiparasitic drugs proven efficient in chronically infected adults, when most patients are diagnosed. Both familial aggregation of CCC cases and the fact that only 30% of infected patients develop CCC suggest there might be a genetic component to disease susceptibility. Moreover, previous case-control studies have identified some genes associated to human susceptibility to CCC. In this paper, we will review the immunopathogenesis and genetics of Chagas disease, highlighting studies that shed light on the differential progression of Chagas disease patients to CCC. PMID:25210230

  12. Immunopathological study of parasitic cholangitis in cetaceans.

    PubMed

    Jaber, J R; Zafra, R; Pérez, J; Suárez-Bonnet, A; González, J F; Carrascosa, C; Andrada, M; Arbelo, M; Fernández, A

    2013-10-01

    This paper describes the immunophenotype of cellular inflammatory infiltrates in chronic cholangitis in six common dolphins (Delphinus delphis), four striped dolphins (Stenella coeruleoalba), three Atlantic spotted dolphins (Stenella frontalis) and one pygmy sperm whale (Kogia Breviceps) found stranded along the coasts of the Canary Islands (Spain). A panel of 5 antibodies previously tested in dolphins (anti-CD3, -IgG, -MHC class II, -S100 protein and -lysozyme) were used. The present work also reports cross reactivity with dolphin antigens of two antibodies not used to date in dolphins (anti-mouse iNOS and anti-mouse Foxp3). The most common type of cholangitis found was chronic granulomatous cholangitis, associated with the presence of the parasite Campula spp., or its eggs in bile ducts. The cellular composition of the hepatic inflammatory infiltrate associated to chronic parasitic cholangitis was closely similar to that found in the cortex of control lymph nodes, including the presence of S100(+) and MHC class II(+) dendritic-like cells in lymphoid follicles and interfollicular areas. Only occasional macrophages expressed iNOS, whereas Foxp3(+) lymphocytes were not found in any of the lesions described in the different types of cholangitis. PMID:23809732

  13. Immunopathologic effects of silicone breast implants.

    PubMed Central

    Teuber, S S; Yoshida, S H; Gershwin, M E

    1995-01-01

    Silicone-gel breast implants have been associated with a myriad of autoimmune and connective tissue disorders by anecdotal reports and small observational series. To date, no prospective epidemiologic studies have been done to substantiate these observations, but an increasing body of literature is being developed and older studies are being recognized that point to immunotoxic or inflammatory effects of these breast implant components. The development of disease due to implants would depend on the interaction of genetic host factors so that only a few patients would potentially be at risk. Based on the example of other chemically mediated disorders, such as scleroderma in association with silica exposure, latency periods of more than 30 years before disease develops may be possible. Herein we review studies on silicone and immunity. PMID:7785255

  14. Current concepts and controversies in prion immunopathology.

    PubMed

    Heikenwalder, Mathias; Prinz, Marco; Heppner, Frank L; Aguzzi, Adriano

    2004-01-01

    Scrapie in sheep and new variant Creutzfeldt-Jakob disease in humans are typically initiated by extracerebral exposure to prions. Both exhibit early prion accumulation in sites of the peripheral lymphoreticular system, such as splenic or lymph nodal germinal centers. In germinal centers, follicular dendritic cells (FDCs), whose development and maintenance depend on lymphotoxin and tumor necrosis factor signaling, are believed to be the main cell type for efficient prion replication in the periphery. Here, we discuss the molecular requirements for prion replication competence in stromal and lymphoid compartments of lymphoid organs. In addition, we examine the preconditions of transepithelial passage of prions in the mucosal-associated lymphoid system. Our results suggest that under specific conditions, efficient prion replication in mesenteric and inguinal lymph nodes is possible in the absence of mature FDCs. M cells are a plausible candidate for the mucosal portal of prion infection. PMID:15126687

  15. Immunopathology of nephropathies associated with malaria*

    PubMed Central

    Houba, V.

    1975-01-01

    Immune complexes play an important role in the pathogenesis of malaria-associated nephropathies. Two main types of lesion are demonstrable: (a) acute (transient—reversible) lesions typical of falciparum infections in man, with mild clinical symptoms developing a week or two after infection. Renal biopsies at that time show deposits of immunoglobulins, complement, and sometimes antigen. The lesions respond to antimalarials. (b) Chronic (progressive) lesions characteristic of quartan infections in man, developing slowly into a chronic stage with persistent proteinuria and gradually deteriorating renal function and hypertension. Renal biopsies at the onset of the disease show deposits of immunoglobulins, complement, and P. malariae antigens in glomerular capillary walls. Antimalarial therapy has no effect. Recent immunochemical findings confirm that these lesions are of the immune-complex type and are associated with malaria infection. However, several questions remain to be solved. PMID:1083308

  16. Chagas Disease Cardiomyopathy: Immunopathology and Genetics

    PubMed Central

    Chevillard, Christophe

    2014-01-01

    Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America and affects ca. 10 million people worldwide. About 30% of Chagas disease patients develop chronic Chagas disease cardiomyopathy (CCC), a particularly lethal inflammatory cardiomyopathy that occurs decades after the initial infection, while most patients remain asymptomatic. Mortality rate is higher than that of noninflammatory cardiomyopathy. CCC heart lesions present a Th1 T-cell-rich myocarditis, with cardiomyocyte hypertrophy and prominent fibrosis. Data suggest that the myocarditis plays a major pathogenetic role in disease progression. Major unmet goals include the thorough understanding of disease pathogenesis and therapeutic targets and identification of prognostic genetic factors. Chagas disease thus remains a neglected disease, with no vaccines or antiparasitic drugs proven efficient in chronically infected adults, when most patients are diagnosed. Both familial aggregation of CCC cases and the fact that only 30% of infected patients develop CCC suggest there might be a genetic component to disease susceptibility. Moreover, previous case-control studies have identified some genes associated to human susceptibility to CCC. In this paper, we will review the immunopathogenesis and genetics of Chagas disease, highlighting studies that shed light on the differential progression of Chagas disease patients to CCC. PMID:25210230

  17. Monocyte-related immunopathologies in trauma patients.

    PubMed

    Laudanski, Krzysztof; Wyczechowska, Dorota

    2005-01-01

    Mechanical trauma is one of the most important causes of morbidity in the developed world. The response of the immune system to mechanical insult is of paramount importance for the patient's recovery. Shortly after trauma, the indiscriminate systemic inflammatory response syndrome (SIRS) is mediated by circulating monocytes (M Øs) and other innate immunity components. Then acquired immunity, limited to the offending pathogen and the site of injury, gradually preponderates. SIRS is followed by the compensatory anti-inflammatory response syndrome (CARS), where the initial inflammatory response is quenched by anti-inflammatory mediators. This precisely regulated process of immune system activation in response to trauma can be easily deviated, resulting in multiorgan failure (MOF) and increased mortality. Excessive activation of inflammatory M Øs in the SIRS phase, premature or exorbitant CARS, a predominance of macrophages (Macs) in the blood stream and peripheral tissues, as well as a depletion of dendritic cells are often seen in trauma patients and contribute to the development of MOF. Here we explore several mechanisms of pathological MØ; activation in patients with severe mechanical traumatic injury without accompanying sepsis. PMID:16088316

  18. Immunopathological Aspects of Experimental Trypanosoma cruzi Reinfections

    PubMed Central

    Reis Machado, Juliana; Silva, Marcos Vinícius; Borges, Diego Costa; da Silva, Crislaine Aparecida; Ramirez, Luis Eduardo; dos Reis, Marlene Antônia; Castellano, Lúcio Roberto; Rodrigues, Virmondes; Rodrigues, Denise Bertulucci Rocha

    2014-01-01

    Chagas disease is caused by Trypanosoma cruzi infection. Besides the host-related factors, such as immune response and genetic background, the parasite, strain, and occurrences of reinfection episodes, may influence disease outcome. Our results demonstrate that both the primary infection and the reinfection with the Colombiana strain are connected with lower survival rate of the mice. After reinfection, parasitaemia is approximately ten times lower than in primary infected animals. Only Colombiana, Colombiana/Colombiana, and Y/Colombiana groups presented amastigote nests in cardiac tissue. Moreover, the mice infected and/or reinfected with the Colombiana strain had more T. cruzi nests, more intense inflammatory infiltrate, and higher in situ expression of TNF-α and IFN-γ than Y strain. Antigen-stimulated spleen cells from infected and/or reinfected animals produced higher levels of TNF-α, IFN-γ, and IL-10. Our results reinforce the idea that Chagas disease outcome is influenced by the strain of the infective parasite, being differentially modulated during reinfection episodes. It highlights the need of control strategies involving parasite strain characterization in endemic areas for Chagas disease. PMID:25050370

  19. Immune Restoration Diseases Reflect Diverse Immunopathological Mechanisms

    PubMed Central

    Price, Patricia; Murdoch, David M.; Agarwal, Upasna; Lewin, Sharon R.; Elliott, Julian H.; French, Martyn A.

    2009-01-01

    Summary: Up to one in four patients infected with human immunodeficiency virus type 1 and given antiretroviral therapy (ART) experiences inflammatory or cellular proliferative disease associated with a preexisting opportunistic infection, which may be subclinical. These immune restoration diseases (IRD) appear to result from the restoration of immunocompetence. IRD associated with intracellular pathogens are characterized by cellular immune responses and/or granulomatous inflammation. Mycobacterial and cryptococcal IRD are attributed to a pathological overproduction of Th1 cytokines. Clinicopathological characteristics of IRD associated with viral infections suggest different pathogenic mechanisms. For example, IRD associated with varicella-zoster virus or JC polyomavirus infection correlate with a CD8 T-cell response in the central nervous system. Exacerbations or de novo presentations of hepatitis associated with hepatitis C virus (HCV) infection following ART may also reflect restoration of pathogen-specific immune responses as titers of HCV-reactive antibodies rise in parallel with liver enzymes and plasma markers of T-cell activation. Correlations between immunological parameters assessed in longitudinal sample sets and clinical presentations are required to illuminate the diverse immunological scenarios described collectively as IRD. Here we present salient clinical features and review progress toward understanding their pathogeneses. PMID:19822893

  20. Coupling Virus-Induced Gene Silencing to Exogenous Green Fluorescence Protein Expression Provides a Highly Efficient System for Functional Genomics in Arabidopsis and across All Stages of Tomato Fruit Development1[C][W

    PubMed Central

    Quadrana, Leandro; Rodriguez, Maria Cecilia; López, Mariana; Bermúdez, Luisa; Nunes-Nesi, Adriano; Fernie, Alisdair R.; Descalzo, Adriana; Asis, Ramón; Rossi, Magdalena; Asurmendi, Sebastian; Carrari, Fernando

    2011-01-01

    Since the advent of the postgenomic era, efforts have focused on the development of rapid strategies for annotating plant genes of unknown function. Given its simplicity and rapidity, virus-induced gene silencing (VIGS) has become one of the preeminent approaches for functional analyses. However, several problems remain intrinsic to the use of such a strategy in the study of both metabolic and developmental processes. The most prominent of these is the commonly observed phenomenon of “sectoring” the tissue regions that are not effectively targeted by VIGS. To better discriminate these sectors, an effective marker system displaying minimal secondary effects is a prerequisite. Utilizing a VIGS system based on the tobacco rattle virus vector, we here studied the effect of silencing the endogenous phytoene desaturase gene (pds) and the expression and subsequent silencing of the exogenous green fluorescence protein (gfp) on the metabolism of Arabidopsis (Arabidopsis thaliana) leaves and tomato (Solanum lycopersicum) fruits. In leaves, we observed dramatic effects on primary carbon and pigment metabolism associated with the photobleached phenotype following the silencing of the endogenous pds gene. However, relatively few pleiotropic effects on carbon metabolism were observed in tomato fruits when pds expression was inhibited. VIGS coupled to gfp constitutive expression revealed no significant metabolic alterations after triggering of silencing in Arabidopsis leaves and a mild effect in mature green tomato fruits. By contrast, a wider impact on metabolism was observed in ripe fruits. Silencing experiments with an endogenous target gene of interest clearly demonstrated the feasibility of cosilencing in this system; however, carefully constructed control experiments are a prerequisite to prevent erroneous interpretation. PMID:21531899

  1. Highly Efficient Virus-induced Gene Silencing (VIGS) in California Poppy (Eschscholzia californica): An Evaluation of VIGS as a Strategy to Obtain Functional Data from Non-model Plants

    PubMed Central

    Wege, Stefanie; Scholz, Andrea; Gleissberg, Stefan; Becker, Annette

    2007-01-01

    Background and Aims Eschscholzia californica (California poppy) is an emerging model plant for ‘evo–devo’ studies from the basal eudicot clade of Papaveraceae. California poppy has a relatively small genome, a short life cycle and, most importantly, it is amenable for transformation. However, since this transformation protocol is time consuming, virus-induced gene silencing (VIGS) was evaluated as a fast method to obtain functional data for California poppy genes. Methods Commercially available California poppy plants were infiltrated with Agrobacterium tumefaciens carrying the tobacco rattle virus plasmids pTRV1 and pTRV2. pTRV2 contained part of the eschscholzia Phytoene Desaturase (EcPDS) gene whose loss of function results in photobleaching of the green parts of the plant and in a lack of floral coloration. The degree and duration of these symptoms was evaluated for vegetative rosettes and plants in flower. Key Results It is shown that VIGS is able to effectively down-regulate the EcPDS gene in eschscholzia. Various degrees of silencing were observed starting <2 weeks after infiltration with Agrobacterium tumefaciens in 92 % of the plants. Tissue with silencing symptoms also showed complete or strong reduction of EcPDS transcripts. Strong silencing resulted in almost completely white petals, fruits, shoots and leaves. Plants with a strong degree of silencing will eventually die off; however, others are able to produce EcPDS gene product even after a strong initial silencing and will recover. Silencing was found to be not always systemic, but was often restricted to certain organs or parts of organs. Conclusions VIGS is an effective, fast and transient method to down-regulate gene expression in eschscholzia. It serves well to detect prominent phenotypes which may become obvious even if some target gene transcript remains in the plant tissue. However, subtle phenotypes will be more difficult to detect, as extremely strong silencing effects occur in <10 % of

  2. Virus-Induced Gene Silencing-Based Functional Analyses Revealed the Involvement of Several Putative Trehalose-6-Phosphate Synthase/Phosphatase Genes in Disease Resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000 in Tomato

    PubMed Central

    Zhang, Huijuan; Hong, Yongbo; Huang, Lei; Liu, Shixia; Tian, Limei; Dai, Yi; Cao, Zhongye; Huang, Lihong; Li, Dayong; Song, Fengming

    2016-01-01

    Trehalose and its metabolism have been demonstrated to play important roles in control of plant growth, development, and stress responses. However, direct genetic evidence supporting the functions of trehalose and its metabolism in defense response against pathogens is lacking. In the present study, genome-wide characterization of putative trehalose-related genes identified 11 SlTPSs for trehalose-6-phosphate synthase, 8 SlTPPs for trehalose-6-phosphate phosphatase and one SlTRE1 for trehalase in tomato genome. Nine SlTPSs, 4 SlTPPs, and SlTRE1 were selected for functional analyses to explore their involvement in tomato disease resistance. Some selected SlTPSs, SlTPPs, and SlTRE1 responded with distinct expression induction patterns to Botrytis cinerea and Pseudomonas syringae pv. tomato (Pst) DC3000 as well as to defense signaling hormones (e.g., salicylic acid, jasmonic acid, and a precursor of ethylene). Virus-induced gene silencing-mediated silencing of SlTPS3, SlTPS4, or SlTPS7 led to deregulation of ROS accumulation and attenuated the expression of defense-related genes upon pathogen infection and thus deteriorated the resistance against B. cinerea or Pst DC3000. By contrast, silencing of SlTPS5 or SlTPP2 led to an increased expression of the defense-related genes upon pathogen infection and conferred an increased resistance against Pst DC3000. Silencing of SlTPS3, SlTPS4, SlTPS5, SlTPS7, or SlTPP2 affected trehalose level in tomato plants with or without infection of B. cinerea or Pst DC3000. These results demonstrate that SlTPS3, SlTPS4, SlTPS5, SlTPS7, and SlTPP2 play roles in resistance against B. cinerea and Pst DC3000, implying the importance of trehalose and tis metabolism in regulation of defense response against pathogens in tomato. PMID:27540389

  3. Virus-Induced Gene Silencing-Based Functional Analyses Revealed the Involvement of Several Putative Trehalose-6-Phosphate Synthase/Phosphatase Genes in Disease Resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000 in Tomato.

    PubMed

    Zhang, Huijuan; Hong, Yongbo; Huang, Lei; Liu, Shixia; Tian, Limei; Dai, Yi; Cao, Zhongye; Huang, Lihong; Li, Dayong; Song, Fengming

    2016-01-01

    Trehalose and its metabolism have been demonstrated to play important roles in control of plant growth, development, and stress responses. However, direct genetic evidence supporting the functions of trehalose and its metabolism in defense response against pathogens is lacking. In the present study, genome-wide characterization of putative trehalose-related genes identified 11 SlTPSs for trehalose-6-phosphate synthase, 8 SlTPPs for trehalose-6-phosphate phosphatase and one SlTRE1 for trehalase in tomato genome. Nine SlTPSs, 4 SlTPPs, and SlTRE1 were selected for functional analyses to explore their involvement in tomato disease resistance. Some selected SlTPSs, SlTPPs, and SlTRE1 responded with distinct expression induction patterns to Botrytis cinerea and Pseudomonas syringae pv. tomato (Pst) DC3000 as well as to defense signaling hormones (e.g., salicylic acid, jasmonic acid, and a precursor of ethylene). Virus-induced gene silencing-mediated silencing of SlTPS3, SlTPS4, or SlTPS7 led to deregulation of ROS accumulation and attenuated the expression of defense-related genes upon pathogen infection and thus deteriorated the resistance against B. cinerea or Pst DC3000. By contrast, silencing of SlTPS5 or SlTPP2 led to an increased expression of the defense-related genes upon pathogen infection and conferred an increased resistance against Pst DC3000. Silencing of SlTPS3, SlTPS4, SlTPS5, SlTPS7, or SlTPP2 affected trehalose level in tomato plants with or without infection of B. cinerea or Pst DC3000. These results demonstrate that SlTPS3, SlTPS4, SlTPS5, SlTPS7, and SlTPP2 play roles in resistance against B. cinerea and Pst DC3000, implying the importance of trehalose and tis metabolism in regulation of defense response against pathogens in tomato. PMID:27540389

  4. Virus induced gene silencing in Lolium temulentum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lolium temulentum L. is valuable as a model species for studying abiotic stress in closely related forage and turf grasses, many of which are polyploid outcrossing species. As with most monocot species, Agrobacterium-mediated transformation of L. temulentum is still challenging, time consuming and n...

  5. Human immunodeficiency virus induced oral candidiasis

    PubMed Central

    Warrier, S. Aravind; Sathasivasubramanian, S.

    2015-01-01

    Human immunodeficiency virus (HIV) infection is a worldwide health problem, which affects in both developing and developed countries. The oral lesions caused due to this disease can drastically change the life of the patient, in terms of quality. We can also know the progression of the disease and also the important immune status of the patient. Lots of information on HIV is known in the developed countries and very less reports are available in the developing countries. The morbidity of HIV disease is due to its association with opportunistic fungal infection and the most common among them is oral candidiasis. Here, we present a case report on an apparently healthy male patient of 39 years, who had oral candidiasis and was one of the indicators for HIV infection. PMID:26538978

  6. Hepatitis C virus-induced hepatocellular carcinoma

    PubMed Central

    Goossens, Nicolas

    2015-01-01

    Hepatitis C virus (HCV) is a leading etiology of hepatocellular carcinoma (HCC). The interaction of HCV with its human host is complex and multilayered; stemming in part from the fact that HCV is a RNA virus with no ability to integrate in the host's genome. Direct and indirect mechanisms of HCV-induced HCC include activation of multiple host pathways such as liver fibrogenic pathways, cellular and survival pathways, interaction with the immune and metabolic systems. Host factors also play a major role in HCV-induced HCC as evidenced by genomic studies identifying polymorphisms in immune, metabolic, and growth signaling systems associated with increased risk of HCC. Despite highly effective direct-acting antiviral agents, the morbidity and incidence of liver-related complications of HCV, including HCC, is likely to persist in the near future. Clinical markers to selectively identify HCV subjects at higher risk of developing HCC have been reported however they require further validation, especially in subjects who have experienced sustained virological response. Molecular biomarkers allowing further refinement of HCC risk are starting to be implemented in clinical platforms, allowing objective stratification of risk and leading to individualized therapy and surveillance for HCV individuals. Another role for molecular biomarker-based stratification could be enrichment of HCC chemoprevention clinical trials leading to smaller sample size, shorter trial duration, and reduced costs. PMID:26157746

  7. Cystatins may confer viral resistance in plants by inhibition of a virus-induced cell death phenomenon in which cysteine proteinases are active: cloning and molecular characterization of a cDNA encoding cysteine-proteinase inhibitor (celostatin) from Celosia cristata (crested cock's comb).

    PubMed

    Gholizadeh, Ashraf; Santha, Ittiaparambu Mana; Kohnehrouz, Bahram Baghban; Lodha, Madan Lal; Kapoor, Harish Chander

    2005-12-01

    Cystatins (cysteine proteinase inhibitors) have been recently used in plants as antiviral strategy against those viruses whose replication involves cysteine proteinase activity. We proposed an idea that cystatins may confer resistance by inhibition of a virus-induced cell-death phenomenon in which cysteine proteinases are active. To test this idea, a full-length cDNA library was constructed from the preflowering stage of Celosia cristata (crested cock's comb) leaves, and a cDNA clone with cystatin domain was isolated using an oligonucleotide probe designed on the basis of the conserved peptide of plant cystatins. It was expressed in an Escherichia coli expression system as a fusion protein. The purified recombinant product, termed 'celostatin' (Celosia cystatin), inhibited the enzymatic activity of papain indicating its cystatin activity and prevented TMV (tobacco mosaic virus)-induced hypersensitive-response cell death in Nicotiana glutinosa (a wild species of tobacco) leaves by 65-70% at the concentration of approx. 50 ng/ml. It also offered resistance against TMV and caused normal growth of the test plant. Since the activity of cysteine proteinases is not involved in the TMV replication process, we speculated that inhibition of the hypersensitive response by celostatin may be due to the inactivation of proteolysis involved in the plant cell death programme, a phenomenon that has already been reported in animal systems. PMID:15842197

  8. IMMUNITY AND IMMUNOPATHOLOGY TO VIRUSES: what decides the outcome?

    PubMed Central

    Rouse, Barry T.; Sehrawat, Sharvan

    2014-01-01

    PREFACE Many viruses infect humans and most are controlled satisfactorily by the immune system with limited damage to host tissues. Some viruses, however, do cause overt damage to the host, either in isolated cases or as a reaction that commonly occurs after infection. The outcome is influenced by properties of the infecting virus, the circumstances of infection and multiple factors controlled by the host. In this Review, we focus on host factors that influence the outcome of viral infection, including genetic susceptibility, the age of the host when infected, the dose and route of infection, the induction of anti-inflammatory cells and proteins as well as the presence of concurrent infections and past exposure to cross-reactive agents. PMID:20577268

  9. Inclusion body myositis and paraproteinemia: incidence and immunopathologic correlations.

    PubMed

    Dalakas, M C; Illa, I; Gallardo, E; Juarez, C

    1997-01-01

    Serum from 70 patients with sporadic inclusion body myositis (IBM) was subjected to agarose gel immunofixation electrophoresis. The IgG extracted from 9 patients with monoclonal proteins, 3 without, and 2 control subjects and was purified, biotinylated, and applied to muscle biopsy sections for immunocytochemistry and to purified muscle protein fractions for immunoblots. Sixteen of 70 (22.8%) patients with IBM, compared with 2% of age-matched controls, had a monoclonal gammopathy characterized as IgG lambda in 9 patients, IgG kappa in 4, IgM kappa in 2, and IgA lambda in 1. The mean age of IBM patients with gammopathy was 60.6 years (range, 35-77 years), compared with 66.1 years (range, 42-80 years) of the IBM patients without gammopathy. The IgG of the patients, more often than that of the control subjects, immunostained myonuclei and recognized various muscle proteins of 35 to 145 kd. We conclude that IBM, regardless of age, is frequently associated with monoclonal gammopathies, which often recognize various muscle components, especially myonuclei, suggesting disturbed immunoregulation. PMID:9005871

  10. Saikosaponin A inhibits influenza A virus replication and lung immunopathology.

    PubMed

    Chen, Jianxin; Duan, Mubing; Zhao, Yaqin; Ling, Fangfang; Xiao, Kun; Li, Qian; Li, Bin; Lu, Chunni; Qi, Wenbao; Zeng, Zhenling; Liao, Ming; Liu, Yahong; Chen, Weisan

    2015-12-15

    Fatal influenza outcomes result from a combination of rapid virus replication and collateral lung tissue damage caused by exaggerated pro-inflammatory host immune cell responses. There are few therapeutic agents that target both biological processes for the attenuation of influenza-induced lung pathology. We show that Saikosaponin A, a bioactive triterpene saponin with previouslyestablished anti-inflammatory effects, demonstrates both in vitro and in vivo anti-viral activity against influenza A virus infections. Saikosaponin A attenuated the replication of three different influenza A virus strains, including a highly pathogenic H5N1 strain, in human alveolar epithelial A549 cells. This anti-viral activity occurred through both downregulation of NF-κB signaling and caspase 3-dependent virus ribonucleoprotein nuclear export as demonstrated by NF-κB subunit p65 and influenza virus nucleoprotein nuclear translocation studies in influenza virus infected A549 cells. Critically, Saikosaponin A also attenuated viral replication, aberrant pro-inflammatory cytokine production and lung histopathology in the widely established H1N1 PR8 model of influenza A virus lethality in C57BL/6 mice. Flow cytometry studies of mouse bronchoalveolar lavage cells revealed that SSa exerted immunomodulatory effects through a selective attenuation of lung neutrophil and monocyte recruitment during the early peak of the innate immune response to PR8 infection. Altogether, our results indicate that Saikosaponin A possesses novel therapeutic potential for the treatment of pathological influenza virus infections. PMID:26637810

  11. Immunopathological analysis of Erdheim-Chester disease with massive ascites.

    PubMed

    Ota, Muneo; Sakamoto, Mayuko; Sato, Kojiro; Yoshida, Yoshihiro; Funakubo Asanuma, Yu; Akiyama, Yuji; Yamakawa, Mitsunori; Mimura, Toshihide

    2012-01-01

    We treated a 77-year-old woman with pleural and pericardial effusion and ascites. Initially, collagen vascular disease was suspected due to the presence of anti-centromere antibodies and suspected complication of pulmonary arterial hypertension. However, soft-tissue abnormalities surrounding the bilateral kidneys detected on computed tomography (CT) and symmetrical lesions of the long bones detected on bone scintigraphy made us consider a diagnosis of Erdheim-Chester disease (ECD), which is a rare form of histiocytosis. We immunochemically analyzed the cells derived from the ascites in detail and confirmed the diagnosis. Immunocytochemical analyses may therefore help to achieve a better understanding of the pathogenesis of this rare disease. PMID:23037484

  12. Dirofilaria immitis. 5. Immunopathology of filarial nephropathy in dogs.

    PubMed Central

    Abramowsky, C. R.; Powers, K. G.; Aikawa, M.; Swinehart, G.

    1981-01-01

    Fourteen beagles infected with larvae (microfilariae) of Dirofilaria immitis, were randomly selected from another study in which the toxic effects of subfilaricidal doses of diethylcarbamazine were being evaluated. This group of 14 dogs, together with 4 uninfected control animals, were variably sacrificed between 14 and 25 months after larval inoculations, and the ensuing renal lesions were studied by light and ultrastructural microscopy and by immunofluorescence and antibody elution techniques. On the basis of these studies, two groups of animals were distinguished. The first group was characterized by a striking pattern of linear fluorescence and fine ultrastructural dense deposits along the glomerular basement membrane, poor antibody response, and an inability to clear microfilariae from the tissues and circulation. The second group, with a nonlinear pattern of fluorescence, was characterized by a strong immune response, efficient elimination of microfilariae, and immunofluorescence and ultrastructural evidence of predominantly mesangiopathic immune complex renal disease. In both groups, elution studies demonstrated tissue deposits of antiworm antibodies, suggesting a filaria-antibody immune-complex nephropathy. No evidence was found for the presence of anti-basement-membrane antibodies. On the basis of a previous experimental model, it is postulated that in the first group of animals with linear fluorescence, the observed lesions may represent a natural form of an immunopathogenic mechanism of glomerular damage in which filarial antigen becomes uniformly localized in the glomerulus and elicits an autologous antibody response. The possible role of the drug diethylcarbamazine in inducing this mechanism of immune injury is discussed. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:7020425

  13. Role of platelet adhesion in homeostasis and immunopathology.

    PubMed Central

    Männel, D N; Grau, G E

    1997-01-01

    Various molecules expressed on the surface of platelets have been shown to mediate the protective or deleterious role of these cells in immuno-inflammatory mechanisms. Increasing evidence points to the involvement of the cell adhesion molecules, gpIIb-IIIa, P-selectin, CD31, LFA-1, and CD36 in the interaction between platelets and endothelial cells as well as other cell types. The possible role of these molecules in the ability of platelets to support endothelium and to protect against tumour necrosis factor mediated cytolysis or parasitic invasion are reviewed. The involvement of platelets as effectors of tissue damage in cerebral malaria, lipopolysaccharide induced pathology, and pulmonary fibrosis is also discussed. This has then been extended to include the intercellular mechanisms underpinning their pathogenic role in metastasis, transplant rejection, stroke, brain hypoxia, and related conditions. A better understanding of the complex regulation and hierarchical organisation of these various platelet adhesion molecules may prove useful in the development of new approaches to the treatment of such diseases. Images PMID:9350300

  14. Immunopathology: autoimmune glial diseases and differentiation from multiple sclerosis.

    PubMed

    Popescu, Bogdan F Gh; Lucchinetti, Claudia F

    2016-01-01

    While multiple sclerosis (MS) is often referred to as an autoimmune inflammatory demyelinating disease, neuromyelitis optica (NMO) is currently the only proven and well-characterized autoimmune disease affecting the glial cells. The target antigen is the water channel aquaporin-4 (AQP4), expressed on astrocytes, and antibodies against AQP4 (AQP4-IgG) are present in the serum of NMO patients. Clinical, serologic, cerebrospinal fluid, and neuroimaging criteria help differentiate NMO from other central nervous system inflammatory demyelinating disorders. Pathologically, the presence of dystrophic astrocytes, myelin vacuolation, granulocytic inflammatory infiltrates, vascular hyalinization, macrophages containing glial fibrillary acidic protein-positive debris and/or the absence of Creutzfeldt-Peters cells is more characteristic, but not specific, for NMO. These findings should prompt the neuropathologist to perform AQP4 immunohistochemistry, and recommend serologic testing for AQP4-IgG to exclude a diagnosis of NMO/NMO spectrum disorder (NMOSD). Loss of AQP4 on biopsied active demyelinating lesions and/or seropositivity for AQP4-IgG may confirm the diagnosis of NMO/NMOSD, which is important because treatments that are suitable for MS can aggravate NMO. Few other putative glial antigens have been postulated, but their pathogenic role remains to be demonstrated. PMID:27112673

  15. Strain differences in Shope fibroma virus. An immunopathologic study.

    PubMed Central

    Strayer, D. S.; Skaletsky, E.; Sell, S.

    1984-01-01

    The pathogenic effects of plaque-purified Boerlage and Patuxent strains of Shope fibroma virus (SFV) in neonatal rabbits are compared with results of previous reports which used nonpurified SFV. Clinically, the Boerlage strain produced large tumors; whereas the same dose of Patuxent strain SFV induced much smaller tumors locally. Neither virus caused metastatic or extensively invasive local spread in our study. Some Patuxent recipients died of respiratory infections prior to sacrifice. However, both groups of rabbits handled the tumor well; the tumor began regressing 15-20 days after inoculation. Histologically, the tumors produced by those viruses were identical. Patuxent strain recipients were otherwise normal. Boerlage strain recipients showed increased persistence of extramedullary hematopoiesis and scattered foci of parenchymal necrosis in their livers. They also showed considerable cell death in thymic lobules. In rabbits given Patuxent strain SFV, virus antigens were detected only in the tumor by immunohistologic examination. Boerlage viral antigens were found in the tumor and overlying skin. We also detected virus systemically in Boerlage recipients: it was present in fixed tissue phagocytes in the spleen and liver and also in parenchymal cells of the lungs, liver, and kidney. Boerlage strain SFV recipients also showed detectable virus in their thymus, both at the periphery of the thymic lobules and in the connective tissue separating thymic lobules from each other. Despite the disseminated nature of the infection, rabbits that received the latter strain fared as well as those receiving Patuxent strain SFV. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 7 p[353]-a Figure 8 Figure 9 Figure 1 p345-a Figure 6 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 PMID:6087669

  16. Immunopathological studies on feline cutaneous and (muco)cutaneous mycobacteriosis.

    PubMed

    Kipar, A; Schiller, I; Baumgärtner, W

    2003-02-10

    Eight cases of feline (muco)cutaneous mycobacteriosis were studied to identify the causative agent and examine for phenotype and functional characteristics (expression of interleukin (IL)-1beta, IL-6, IL-12, tumour necrosis factor-alpha and inducible nitric oxide synthase) of the inflammatory cells. Polymerase chain reaction and sequencing identified the causative agents as Mycobacterium tuberculosis or M. avium complex in each four cases. Lesions were characterised by pyogranulomatous infiltration, with variability in the presence and size of necrotic areas, the presence of multinucleated giant cells and the degree of lymphocyte infiltration. Macrophages were positive for myeloid/histiocyte antigen (calprotectin), suggesting they represented freshly recruited monocytes; further differentiation to epithelioid cells and multinucleated giant cells was associated with loss of the myeloid/histiocyte antigen. Lymphocytes were found disseminated in the infiltrate (predominantly T cells) and as B cell-dominated accumulations mainly in the periphery of the lesions. Acid-fast bacilli were numerous. In M. tuberculosis complex infection, extracellular bacilli were most prominent, whereas in M. avium complex infection, bacilli were mainly located intracellularly. All cytokines examined as well as inducible nitric oxide synthase (iNOS) were variably expressed by macrophages, epithelioid cells and multinucleated giant cells. Expression was most intense in degenerating macrophages loaded with intracellular bacilli, but was also seen cell-free within necrotic areas. The intense induction of cytokine and iNOS expression especially in infected macrophages suggests a relatively low virulence for these infectious agents in cats. Furthermore, the confinement of the bacilli to lesions indicates a successful response to infection. PMID:12586480

  17. Tracking the immunopathological response to Pseudomonas aeruginosa during respiratory infections

    PubMed Central

    Cigana, Cristina; Lorè, Nicola Ivan; Riva, Camilla; De Fino, Ida; Spagnuolo, Lorenza; Sipione, Barbara; Rossi, Giacomo; Nonis, Alessandro; Cabrini, Giulio; Bragonzi, Alessandra

    2016-01-01

    Repeated cycles of infections, caused mainly by Pseudomonas aeruginosa, combined with a robust host immune response and tissue injury, determine the course and outcome of cystic fibrosis (CF) lung disease. As the disease progresses, P. aeruginosa adapts to the host modifying dramatically its phenotype; however, it remains unclear whether and how bacterial adaptive variants and their persistence influence the pathogenesis and disease development. Using in vitro and murine models of infection, we showed that P. aeruginosa CF-adaptive variants shaped the innate immune response favoring their persistence. Next, we refined a murine model of chronic pneumonia extending P. aeruginosa infection up to three months. In this model, including CFTR-deficient mice, we unveil that the P. aeruginosa persistence lead to CF hallmarks of airway remodelling and fibrosis, including epithelial hyperplasia and structure degeneration, goblet cell metaplasia, collagen deposition, elastin degradation and several additional markers of tissue damage. This murine model of P. aeruginosa chronic infection, reproducing CF lung pathology, will be instrumental to identify novel molecular targets and test newly tailored molecules inhibiting chronic inflammation and tissue damage processes in pre-clinical studies. PMID:26883959

  18. Pattern Recognition Receptors in Innate Immunity, Host Defense, and Immunopathology

    ERIC Educational Resources Information Center

    Suresh, Rahul; Mosser, David M.

    2013-01-01

    Infection by pathogenic microbes initiates a set of complex interactions between the pathogen and the host mediated by pattern recognition receptors. Innate immune responses play direct roles in host defense during the early stages of infection, and they also exert a profound influence on the generation of the adaptive immune responses that ensue.…

  19. Effects of aging on the immunopathological response to sepsis

    PubMed Central

    Turnbull, Isaiah R.; Clark, Andrew T.; Stromberg, Paul E.; Dixon, David J.; Woolsey, Cheryl A.; Davis, Christopher G.; Hotchkiss, Richard S.; Buchman, Timothy G.; Coopersmith, Craig M.

    2009-01-01

    Objective Aging is associated with increased inflammation following sepsis. The purpose of this study was to determine if this represents a fundamental age-based difference in the host response or is secondary to the increased mortality seen in aged hosts. Design Prospective, randomized controlled study. Setting Animal laboratory in a university medical center. Subjects Young (6–12 week) and aged (20–24 month) FVB/N mice. Interventions Mice were subjected to 2×25 or 1×30 cecal ligation and puncture (CLP). Measurements and Main Results Survival was similar in young mice subjected to 2×25 CLP and aged mice subjected to 1×30 CLP (p=0.15). Young mice subjected to 1×30 CLP had improved survival compared to both other groups (p<0.05). When injury was held constant but mortality was greater, both systemic and peritoneal levels of TNF-α, IL-6, IL-10 and MCP-1 were elevated 24 hours after CLP in aged animals compared to young animals (p<0.05). When mortality was similar but injury severity was different, there were no significant differences in systemic cytokines between aged mice and young mice. In contrast, peritoneal levels of TNF-α, IL-6, and IL-10 were higher in aged mice subjected to 1×30 CLP than young mice subjected to 2×25 CLP despite their similar mortalities (p<0.05). There were no significant differences in either bacteremia or peritoneal cultures when animals of different ages sustained similar injuries or had different injuries with similar mortalities. Conclusions Aged mice are more likely to die from sepsis than young mice when subjected to an equivalent insult, and this is associated with increases in both systemic and local inflammation. There is an exaggerated local but not systemic inflammatory response in aged mice compared to young mice when mortality is similar. This suggests that systemic processes that culminate in death may be age-independent, but the local inflammatory response may be greater with aging. PMID:19237912

  20. Saikosaponin A inhibits influenza A virus replication and lung immunopathology

    PubMed Central

    Zhao, Yaqin; Ling, Fangfang; Xiao, Kun; Li, Qian; Li, Bin; Lu, Chunni; Qi, Wenbao; Zeng, Zhenling; Liao, Ming; Liu, Yahong; Chen, Weisan

    2015-01-01

    Fatal influenza outcomes result from a combination of rapid virus replication and collateral lung tissue damage caused by exaggerated pro-inflammatory host immune cell responses. There are few therapeutic agents that target both biological processes for the attenuation of influenza-induced lung pathology. We show that Saikosaponin A, a bioactive triterpene saponin with previouslyestablished anti-inflammatory effects, demonstrates both in vitro and in vivo anti-viral activity against influenza A virus infections. Saikosaponin A attenuated the replication of three different influenza A virus strains, including a highly pathogenic H5N1 strain, in human alveolar epithelial A549 cells. This anti-viral activity occurred through both downregulation of NF-κB signaling and caspase 3-dependent virus ribonucleoprotein nuclear export as demonstrated by NF-κB subunit p65 and influenza virus nucleoprotein nuclear translocation studies in influenza virus infected A549 cells. Critically, Saikosaponin A also attenuated viral replication, aberrant pro-inflammatory cytokine production and lung histopathology in the widely established H1N1 PR8 model of influenza A virus lethality in C57BL/6 mice. Flow cytometry studies of mouse bronchoalveolar lavage cells revealed that SSa exerted immunomodulatory effects through a selective attenuation of lung neutrophil and monocyte recruitment during the early peak of the innate immune response to PR8 infection. Altogether, our results indicate that Saikosaponin A possesses novel therapeutic potential for the treatment of pathological influenza virus infections. PMID:26637810

  1. HLA-B27 Anterior Uveitis: Immunology and Immunopathology.

    PubMed

    Wakefield, Denis; Yates, William; Amjadi, Shahriar; McCluskey, Peter

    2016-08-01

    Acute anterior uveitis (AAU) is the commonest type of uveitis and HLA-B27 AAU is the most frequently recognized type of acute anterior uveitis and anterior uveitis overall. Recent evidence indicates that acute anterior uveitis is a heterogenous disease, is polygenic and is frequently associated with the spondyloarthropathies (SpA). Studies of patients with AAU and animal models of disease indicate a role for innate immunity, the IL-23 cytokine pathway and exogenous factors, in the pathogenesis of both SpA and acute anterior uveitis. Recently described genetic associations cluster around immunologic pathways, including the IL-17 and IL-23 pathways, antigen processing and presentation, and lymphocyte development and activation. Patients with ankylosing spondylitis (AS) and AAU share other genetic markers, such as ERAP-1, which show strong evidence of gene-gene interaction and point to new mechanisms of disease pathogenesis. These observations have major implications for understanding the pathogenesis of HLA-B27 diseases, such as AAU, and may lead to the development of more specific therapy for AAU. Received 6 January 2016; revised 6 February 2016; accepted 18 February 2016; published online 31 May 2016. PMID:27245590

  2. Tracking the immunopathological response to Pseudomonas aeruginosa during respiratory infections.

    PubMed

    Cigana, Cristina; Lorè, Nicola Ivan; Riva, Camilla; De Fino, Ida; Spagnuolo, Lorenza; Sipione, Barbara; Rossi, Giacomo; Nonis, Alessandro; Cabrini, Giulio; Bragonzi, Alessandra

    2016-01-01

    Repeated cycles of infections, caused mainly by Pseudomonas aeruginosa, combined with a robust host immune response and tissue injury, determine the course and outcome of cystic fibrosis (CF) lung disease. As the disease progresses, P. aeruginosa adapts to the host modifying dramatically its phenotype; however, it remains unclear whether and how bacterial adaptive variants and their persistence influence the pathogenesis and disease development. Using in vitro and murine models of infection, we showed that P. aeruginosa CF-adaptive variants shaped the innate immune response favoring their persistence. Next, we refined a murine model of chronic pneumonia extending P. aeruginosa infection up to three months. In this model, including CFTR-deficient mice, we unveil that the P. aeruginosa persistence lead to CF hallmarks of airway remodelling and fibrosis, including epithelial hyperplasia and structure degeneration, goblet cell metaplasia, collagen deposition, elastin degradation and several additional markers of tissue damage. This murine model of P. aeruginosa chronic infection, reproducing CF lung pathology, will be instrumental to identify novel molecular targets and test newly tailored molecules inhibiting chronic inflammation and tissue damage processes in pre-clinical studies. PMID:26883959

  3. IL-33/ST2 axis in inflammation and immunopathology.

    PubMed

    Milovanovic, Marija; Volarevic, Vladislav; Radosavljevic, Gordana; Jovanovic, Ivan; Pejnovic, Nada; Arsenijevic, Nebojsa; Lukic, Miodrag L

    2012-04-01

    Interleukin-33 (IL-33), a member of the IL-1 family of cytokines, binds to its plasma membrane receptor, heterodimeric complex consisted of membrane-bound ST2L and IL-1R accessory protein, inducing NFkB and MAPK activation. IL-33 exists as a nuclear precursor and may act as an alarmin, when it is released after cell damage or as negative regulator of NFκB gene transcription, when acts in an intracrine manner. ST2L is expressed on several immune cells: Th2 lymphocytes, NK, NKT and mast cells and on cells of myeloid lineage: monocytes, dendritic cells and granulocytes. IL-33/ST2 axis can promote both Th1 and Th2 immune responses depending on the type of activated cell and microenvironment and cytokine network in damaged tissue. We previously described and discuss here the important role of IL-33/ST2 axis in experimental models of type 1 diabetes, experimental autoimmune encephalomyelitis, fulminant hepatitis and breast cancer. We found that ST2 deletion enhance the development of T cell-mediated autoimmune disorders, EAE and diabetes mellitus type I. Disease development was accompanied by dominantly Th1/Th17 immune response but also higher IL-33 production, which suggest that IL-33 in receptor independent manner could promote the development of inflammatory autoreactive T cells. IL-33/ST2 axis has protective role in Con A hepatitis. ST2-deficient mice had more severe hepatitis with higher influx of inflammatory cells in liver and dominant Th1/Th17 systemic response. Pretreatment of mice with IL-33 prevented Con A-induced liver damage through prevention of apoptosis of hepatocytes and Th2 amplification. Deletion of IL-33/ST2 axis enhances cytotoxicity of NK cells, production of IFN-γ in these cells and systemic production of IFN-γ, IL-17 and TNF-α, which leads to attenuated tumor growth. IL-33 treatment of tumor-bearing mice suppresses activity of NK cells, dendritic cell maturation and enhances alternative activation of macrophages. In conclusion, we observed that IL-33 has attenuated anti-inflammatory effects in T cell-mediated responses and that both IL-33 and ST2 could be further explored as potential therapeutic targets in treatment of immune-mediated diseases. PMID:22392053

  4. Immune-mediated demyelination--immunopathological basis for electrophysiological changes.

    PubMed

    Saida, T; Saida, K

    1982-01-01

    A focal immune-mediated demyelinating lesion of peripheral nerve was produced by intraneural injection of antiserum to galactocerebroside, a major glycosphingolipid hapten common in CNS and PNS myelin. This model provides an excellent system for correlative studies of physiological and pathological alterations in the processes of demyelination, because the time course of such changes is predictable from animal to animal. Twenty minutes after antiserum injection, Schwann cells showed focal cytoplasmic outpouching and their external mesaxons opened. Between 1 and 8 h after injection "melting," splitting, vesiculation and vacuolation of myelin became increasingly prominent at paranodal regions and Schmidt-Lantermann clefts, with concomitant degenerative changes in Schwann cell cytoplasm. Disruption of myelin in the paranodal region with detachment of the outermost paranodal myelin loops from paranodal axon resulted in an increase in nodal surface area. This seems to be the most critical anatomical alteration responsible for the early changes in propagation of nerve impulses in this antibody-mediated demyelinating lesion. Between 8 h and 3 days axons became demyelinated progressively over several internodes by macrophage phagocytosis. The onset of clinical and saltatory conduction recovery from the lesion corresponded to the appearance of 2-8 myelin lamellae around each remyelinating axon. PMID:6962042

  5. Modeling the Lymphocytic Choriomeningitis Virus: Insights into understanding its epidemiology in the wild

    NASA Astrophysics Data System (ADS)

    Contreras, Christy; McKay, John; Blattman, Joseph; Holechek, Susan

    2015-03-01

    The lymphocytic choriomenigitis virus (LCMV) is a rodent-spread virus commonly recognized as causing neurological disease that exhibits asymptomatic pathology. The virus is a pathogen normally carried among rodents that can be transmitted to humans by direct or indirect contact with the virus in excretions and secretions from rodents and can cause aseptic meningitis and other conditions in humans. We consider an epidemiological system within rodent populations modeled by a system of ordinary differential equations that captures the dynamics of the diseases transmission and present our findings. The asymptotic nature of the pathogen plays a large role in its spread within a given population, which has motivated us to expand upon an existing SIRC model (Holechek et al in preparation) that accounts for susceptible-, infected-, recovered-, and carrier-mice on the basis of their gender. We are interested in observing and determining the conditions under which the carrier population will reach a disease free equilibrium, and we focus our investigation on the sensitivity of our model to gender, pregnancy related infection, and reproduction rate conditions.

  6. Notes from the Field: Lymphocytic Choriomeningitis Virus Meningoencephalitis from a Household Rodent Infestation - Minnesota, 2015.

    PubMed

    Talley, Pamela; Holzbauer, Stacy; Smith, Kirk; Pomputius, William

    2016-03-11

    On April 20, 2015, a female aged 15 years sought care at her pediatrician's office after 5 days of fever, myalgia, left parietal headache, and photophobia. A rapid influenza assay was negative, and erythrocyte sedimentation rate and total white blood cell count were normal. She improved with symptomatic care at home, but returned to her pediatrician's office on April 28, reporting recurrence of her headache and photophobia and new onset of a stiff neck. She was admitted to the hospital, where she was febrile to 102.9°F (39.4°C) and had meningismus. Computed tomography scan of her head was normal, and a cerebrospinal fluid (CSF) analysis showed a markedly elevated white blood cell count with 68% lymphocytes, low glucose, and a negative Gram stain. She was treated empirically for both bacterial and herpes simplex virus meningitis. The patient's hospital course was notable for hypotension (blood pressure 81/50), irritability, and pancreatitis with a peak lipase of 8,627 U/L. CSF cultures yielded no growth, and CSF polymerase chain reaction (PCR) testing for herpes simplex virus was negative. Nucleic acid amplification testing, acid-fast bacilli stain, and acid-fast bacilli cultures of CSF were negative for Mycobacterium tuberculosis. Results of investigations for human immunodeficiency virus, syphilis, Lyme disease, human herpesvirus 6 and 7, and species of Babesia, Toxoplasma, Histoplasma, Cryptococcus, Blastomyces, and Brucella were negative. She recovered and was discharged on hospital day 11 with no apparent sequelae. PMID:26963688

  7. Early antiviral response and virus-induced genes in fish.

    PubMed

    Verrier, Eloi R; Langevin, Christelle; Benmansour, Abdenour; Boudinot, Pierre

    2011-12-01

    In fish as in mammals, virus infections induce changes in the expression of many host genes. Studies conducted during the last fifteen years revealed a major contribution of the interferon system in fish antiviral response. This review describes the screening methods applied to compare the impact of virus infections on the transcriptome in different fish species. These approaches identified a "core" set of genes that are strongly induced in most viral infections. The "core" interferon-induced genes (ISGs) are generally conserved in vertebrates, some of them inhibiting a wide range of viruses in mammals. A selection of ISGs -PKR, vig-1/viperin, Mx, ISG15 and finTRIMs - is further analyzed here to illustrate the diversity and complexity of the mechanisms involved in establishing an antiviral state. Most of the ISG-based pathways remain to be directly determined in fish. Fish ISGs are often duplicated and the functional specialization of multigenic families will be of particular interest for future studies. PMID:21414349

  8. Active immunization by a dengue virus-induced cytokine.

    PubMed Central

    Chaturvedi, U C; Mukerjee, R; Dhawan, R

    1994-01-01

    Dengue type 2 virus (DV)-induced cytotoxic factor (CF) is capable of reproducing various pathological lesions in mice that are seen in human dengue. The present study was undertaken to investigate the protective effect of active immunization of mice with CF. Mice were immunized with 5 microgram of CF and prevention of CF-induced increase in capillary permeability and damage to the blood-brain barrier were studied at weekly intervals, up to 48 weeks, by challenging with 3 microgram of CF. Maximum protection against increase in capillary permeability and damage to the blood-brain barrier was observed in week 4 after immunization. A breakthrough in the protection occurred with higher doses of CF in a dose-dependent manner. Challenge with a lethal intracerebral (i.c.) dose of DV showed significantly prolonged mean survival time and delayed onset of symptoms of sickness in the immunized mice compared with the normal mice, but the titre of the virus in the brain was similar in the two groups. On i.p. challenge with the virus the protection against damage to the blood-brain barrier was 86 +/- 7% at week 4 and 17 +/- 4% at week 26 after immunization. Sera obtained from the immunized mice showed the presence of CF-specific antibodies by ELISA, Western blot, and by neutralization of the cytotoxic activity of CF in vitro. The present study describes successful prevention of a cytokine-induced pathology by specific active immunization. PMID:8187327

  9. Microglia retard dengue virus-induced acute viral encephalitis

    PubMed Central

    Tsai, Tsung-Ting; Chen, Chia-Ling; Lin, Yee-Shin; Chang, Chih-Peng; Tsai, Cheng-Chieh; Cheng, Yi-Lin; Huang, Chao-Ching; Ho, Chien-Jung; Lee, Yi-Chao; Lin, Liang-Tzung; Jhan, Ming-Kai; Lin, Chiou-Feng

    2016-01-01

    Patients with dengue virus (DENV) infection may also present acute viral encephalitis through an unknown mechanism. Here, we report that encephalitic DENV-infected mice exhibited progressive hunchback posture, limbic seizures, limbic weakness, paralysis, and lethality 7 days post-infection. These symptoms were accompanied by CNS inflammation, neurotoxicity, and blood-brain barrier destruction. Microglial cells surrounding the blood vessels and injured hippocampus regions were activated by DENV infection. Pharmacologically depleting microglia unexpectedly increased viral replication, neuropathy, and mortality in DENV-infected mice. In microglia-depleted mice, the DENV infection-mediated expression of antiviral cytokines and the infiltration of CD8-positive cytotoxic T lymphocytes (CTLs) was abolished. DENV infection prompted the antigen-presenting cell-like differentiation of microglia, which in turn stimulated CTL proliferation and activation. These results suggest that microglial cells play a key role in facilitating antiviral immune responses against DENV infection and acute viral encephalitis. PMID:27279150

  10. Advances in the treatment of virus-induced asthma.

    PubMed

    Tay, Hock; Wark, Peter A B; Bartlett, Nathan W

    2016-06-01

    Viral exacerbations continue to represent the major burden in terms of morbidity, mortality and health care costs associated with asthma. Those at greatest risk for acute asthma are those with more severe airways disease and poor asthma control. It is this group with established asthma in whom acute exacerbations triggered by virus infections remain a serious cause of increased morbidity. A range of novel therapies are emerging to treat asthma and in particular target this group with poor disease control, and in most cases their efficacy is now being judged by their ability to reduce the frequency of acute exacerbations. Critical for the development of new treatment approaches is an improved understanding of virus-host interaction in the context of the asthmatic airway. This requires research into the virology of the disease in physiological models in conjunction with detailed phenotypic characterisation of asthma patients to identify targets amenable to therapeutic intervention. PMID:27088397

  11. A Case of Chikungunya Virus Induced Arthralgia Responsive to Colchicine

    PubMed Central

    Redel, Henry

    2016-01-01

    Chikungunya virus is an emerging infectious disease that has started circulating throughout the Americas and Caribbean. It can lead to persistent arthralgia lasting months to years. Treatment has been symptomatic with nonsteroidal anti-inflammatory medications. This case report describes a trial of colchicine for chikungunya arthralgia in 1 patient. PMID:27419183

  12. Microglia retard dengue virus-induced acute viral encephalitis.

    PubMed

    Tsai, Tsung-Ting; Chen, Chia-Ling; Lin, Yee-Shin; Chang, Chih-Peng; Tsai, Cheng-Chieh; Cheng, Yi-Lin; Huang, Chao-Ching; Ho, Chien-Jung; Lee, Yi-Chao; Lin, Liang-Tzung; Jhan, Ming-Kai; Lin, Chiou-Feng

    2016-01-01

    Patients with dengue virus (DENV) infection may also present acute viral encephalitis through an unknown mechanism. Here, we report that encephalitic DENV-infected mice exhibited progressive hunchback posture, limbic seizures, limbic weakness, paralysis, and lethality 7 days post-infection. These symptoms were accompanied by CNS inflammation, neurotoxicity, and blood-brain barrier destruction. Microglial cells surrounding the blood vessels and injured hippocampus regions were activated by DENV infection. Pharmacologically depleting microglia unexpectedly increased viral replication, neuropathy, and mortality in DENV-infected mice. In microglia-depleted mice, the DENV infection-mediated expression of antiviral cytokines and the infiltration of CD8-positive cytotoxic T lymphocytes (CTLs) was abolished. DENV infection prompted the antigen-presenting cell-like differentiation of microglia, which in turn stimulated CTL proliferation and activation. These results suggest that microglial cells play a key role in facilitating antiviral immune responses against DENV infection and acute viral encephalitis. PMID:27279150

  13. GMCSF-armed vaccinia virus induces an antitumor immune response.

    PubMed

    Parviainen, Suvi; Ahonen, Marko; Diaconu, Iulia; Kipar, Anja; Siurala, Mikko; Vähä-Koskela, Markus; Kanerva, Anna; Cerullo, Vincenzo; Hemminki, Akseli

    2015-03-01

    Oncolytic Western Reserve strain vaccinia virus selective for epidermal growth factor receptor pathway mutations and tumor-associated hypermetabolism was armed with human granulocyte-macrophage colony-stimulating factor (GMCSF) and a tdTomato fluorophore. As the assessment of immunological responses to human transgenes is challenging in the most commonly used animal models, we used immunocompetent Syrian golden hamsters, known to be sensitive to human GMCSF and semipermissive to vaccinia virus. Efficacy was initially tested in vitro on various human and hamster cell lines and oncolytic potency of transgene-carrying viruses was similar to unarmed virus. The hGMCSF-encoding virus was able to completely eradicate subcutaneous pancreatic tumors in hamsters, and to fully protect the animals from subsequent rechallenge with the same tumor. Induction of specific antitumor immunity was also shown by ex vivo co-culture experiments with hamster splenocytes. In addition, histological examination revealed increased infiltration of neutrophils and macrophages in GMCSF-virus-treated tumors. These findings help clarify the mechanism of action of GMCSF-armed vaccinia viruses undergoing clinical trials. PMID:25042001

  14. Epstein-Barr Virus Induced Epigenetic Alterations Following Transient Infection

    PubMed Central

    Queen, Krista J.; Shi, Mingxia; Zhang, Fangfang; Cvek, Urska; Scott, Rona S.

    2012-01-01

    Epstein-Barr virus (EBV) is a known tumor virus associated with an increasing array of malignancies; however, the association of the virus with certain malignancies is often erratic. To determine EBV’s contributions to tumorigenesis in a setting of incomplete association, a transient model of infection was established where a clonal CCL185 carcinoma cell line infected with recombinant EBV was allowed to lose viral genomes by withdrawal of selection pressure. Global gene expression comparing EBV-negative, transiently infected clones to uninfected controls identified expression changes in over 1000 genes. Among downregulated genes, several genes known to be DNA methylated in cancer were identified including E-cadherin and PYCARD. A cadherin switch, increased motility and enhanced cellular invasiveness present in EBV-positive cells were retained following viral loss indicating an epigenetic effect. Repression of PYCARD expression was due to increased promoter CpG methylation, whereas loss of E-cadherin expression after transient EBV infection did not correlate with increased DNA methylation of the E-cadherin promoter. Rather, repression of E-cadherin was consistent with formation of a repressive chromatin state. Decreased histone 3 or 4 acetylation at the promoter and 5’ end of the E-cadherin gene was observed in an EBV-negative, transiently infected clone relative to the uninfected controls. These results suggest that EBV can stably alter gene expression in a heritable fashion in formerly infected cells, while its own contribution to the oncogenic process is masked. PMID:23047626

  15. Potential mechanisms of hepatitis B virus induced liver injury.

    PubMed

    Suhail, Mohd; Abdel-Hafiz, Hany; Ali, Ashraf; Fatima, Kaneez; Damanhouri, Ghazi A; Azhar, Esam; Chaudhary, Adeel Ga; Qadri, Ishtiaq

    2014-09-21

    Chronic active hepatitis (CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma. The histological end points of CAH are chronic inflammation, fibrosis and cirrhosis which are coupled with increased DNA synthesis in cirrhotic vs healthy normal livers. The potential mechanism involved in CAH includes a combination of processes leading to liver cell necrosis, inflammation and cytokine production and liver scaring (fibrosis). The severity of liver damage is regulated by Hepatitis B virus genotypes and viral components. The viral and cellular factors that contribute to liver injury are discussed in this article. Liver injury caused by the viral infection affects many cellular processes such as cell signaling, apoptosis, transcription, DNA repair which in turn induce radical effects on cell survival, growth, transformation and maintenance. The consequence of such perturbations is resulted in the alteration of bile secretion, gluconeogenesis, glycolysis, detoxification and metabolism of carbohydrates, proteins, fat and balance of nutrients. The identification and elucidation of the molecular pathways perturbed by the viral proteins are important in order to design effective strategy to minimize and/or restore the hepatocytes injury. PMID:25253946

  16. A Case of Chikungunya Virus Induced Arthralgia Responsive to Colchicine.

    PubMed

    Redel, Henry

    2016-04-01

    Chikungunya virus is an emerging infectious disease that has started circulating throughout the Americas and Caribbean. It can lead to persistent arthralgia lasting months to years. Treatment has been symptomatic with nonsteroidal anti-inflammatory medications. This case report describes a trial of colchicine for chikungunya arthralgia in 1 patient. PMID:27419183

  17. Effect of dengue virus-induced cytotoxin on capillary permeability.

    PubMed Central

    Dhawan, R.; Khanna, M.; Chaturvedi, U. C.; Mathur, A.

    1990-01-01

    Capillary permeability is increased in cases of dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) but its genesis is not known. Dengue type 2 virus (DV) induces production of a cytokine (CF2) by mouse macrophages. The present study was undertaken to investigate the effect of CF2 on capillary permeability. It was observed that intraperitoneal inoculation of CF2 in mice increased the capillary permeability in a dose-dependent manner, as shown by leakage of intravenously injected radioactive iodine (125I) or Evan's blue dye in the peritoneal cavity. Peak leakage occurred at 30 min and the vascular integrity was restored by 1-2 h. The increase in capillary permeability was abrogated by pretreatment of mice with avil (H1 receptor blocker) but not by ranitidine (H2 receptor blocker). The findings thus show that DV-induced CF2 increases the capillary permeability via release of histamine. PMID:2310617

  18. Marek's disease virus induced transient paralysis--a closer look

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marek’s Disease (MD) is a lymphoproliferative disease of domestic chickens caused by a highly cell-associated alpha herpesvirus, Marek’s disease virus (MDV). Clinical signs of MD include depression, crippling, weight loss, and transient paralysis (TP). TP is a disease of the central nervous system...

  19. Potential mechanisms of hepatitis B virus induced liver injury

    PubMed Central

    Suhail, Mohd; Abdel-Hafiz, Hany; Ali, Ashraf; Fatima, Kaneez; Damanhouri, Ghazi A; Azhar, Esam; Chaudhary, Adeel GA; Qadri, Ishtiaq

    2014-01-01

    Chronic active hepatitis (CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma. The histological end points of CAH are chronic inflammation, fibrosis and cirrhosis which are coupled with increased DNA synthesis in cirrhotic vs healthy normal livers. The potential mechanism involved in CAH includes a combination of processes leading to liver cell necrosis, inflammation and cytokine production and liver scaring (fibrosis). The severity of liver damage is regulated by Hepatitis B virus genotypes and viral components. The viral and cellular factors that contribute to liver injury are discussed in this article. Liver injury caused by the viral infection affects many cellular processes such as cell signaling, apoptosis, transcription, DNA repair which in turn induce radical effects on cell survival, growth, transformation and maintenance. The consequence of such perturbations is resulted in the alteration of bile secretion, gluconeogenesis, glycolysis, detoxification and metabolism of carbohydrates, proteins, fat and balance of nutrients. The identification and elucidation of the molecular pathways perturbed by the viral proteins are important in order to design effective strategy to minimize and/or restore the hepatocytes injury. PMID:25253946

  20. Molecular mechanism of hepatitis B virus-induced hepatocarcinogenesis

    PubMed Central

    Tarocchi, Mirko; Polvani, Simone; Marroncini, Giada; Galli, Andrea

    2014-01-01

    Hepatitis B virus (HBV) infection is a global public health problem with approximately 2 billion people that have been exposed to the virus. HBV is a member of a family of small, enveloped DNA viruses called hepadnaviruses, and has a preferential tropism for hepatocytes of mammals and birds. Epidemiological studies have proved a strong correlation between chronic hepatitis B virus infection and the development of hepatocellular carcinoma (HCC). HCC is the fifth most common malignancy with about 700000 new cases each year, and more than 50% of them arise in HBV carriers. A large number of studies describe the way in which HBV can contribute to HCC development. Multiple mechanisms have been proposed, including the accumulation of genetic damage due to immune-mediated hepatic inflammation and the induction of oxidative stress. There is evidence of the direct effects of the viral proteins HBx and HBs on the cell biology. Integration of HBV-DNA into the human genome is considered an early event in the carcinogenic process and can induce, through insertional mutagenesis, the alteration of gene expression and chromosomal instability. HBV has also epigenetic effects through the modification of the genomic methylation status. Furthermore, the virus plays an important role in the regulation of microRNA expression. This review will summarize the many mechanisms involved in HBV-related liver carcinogenesis. PMID:25206269

  1. Herpes simplex virus induces the replication of foreign DNA

    SciTech Connect

    Danovich, R.M.; Frenkel, N.

    1988-08-01

    Plasmids containing the simian virus 40 (SV40) DNA replication origin and the large T gene are replicated in Vero monkey cells but not in rabbit skin cells. Efficient replication of the plasmids was observed in rabbit cells infected with herpes simplex virus type 1 (HSV-1) and HSV-2. The HSV-induced replication required the large T antigen and the SV40 replication origin. However, it produced concatemeric molecules resembling replicative intermediates of HSV DNA and was sensitive to phosphonoacetate at concentrations known to inhibit the HSV DNA polymerase. Therefore, it involved the HSV DNA polymerase itself or a viral gene product(s) which was expressed following the replication of HSV DNA. Analyses of test plasmids lacking SV40 or HSV DNA sequences showed that, under some conditions. HSV also induced low-level replication of test plasmids containing no known eucaryotic replication origins. Together, these results show that HSV induces a DNA replicative activity which amplifies foreign DNA. The relevance of these findings to the putative transforming potential of HSV is discussed.

  2. Herpes simplex virus induces the replication of foreign DNA.

    PubMed Central

    Danovich, R M; Frenkel, N

    1988-01-01

    Plasmids containing the simian virus 40 (SV40) DNA replication origin and the large T gene are replicated efficiently in Vero monkey cells but not in rabbit skin cells. Efficient replication of the plasmids was observed in rabbit skin cells infected with herpes simplex virus type 1 (HSV-1) and HSV-2. The HSV-induced replication required the large T antigen and the SV40 replication origin. However, it produced concatemeric molecules resembling replicative intermediates of HSV DNA and was sensitive to phosphonoacetate at concentrations known to inhibit the HSV DNA polymerase. Therefore, it involved the HSV DNA polymerase itself or a viral gene product(s) which was expressed following the replication of HSV DNA. Analyses of test plasmids lacking SV40 or HSV DNA sequences showed that, under some conditions, HSV also induced low-level replication of test plasmids containing no known eucaryotic replication origins. Together, these results show that HSV induces a DNA replicative activity which amplifies foreign DNA. The relevance of these findings to the putative transforming potential of HSV is discussed. Images PMID:2850486

  3. Exogenous avian leukosis virus-induced activation of the ERK/AP1 pathway is required for virus replication and correlates with virus-induced tumorigenesis

    PubMed Central

    Dai, Manman; Feng, Min; Ye, Yu; Wu, Xiaochan; Liu, Di; Liao, Ming; Cao, Weisheng

    2016-01-01

    A proteomics approach was used to reveal the up-regulated proteins involved in the targeted mitogen-activated protein kinase (MAPK) signal transduction pathway in DF-1 cells after ALV subgroup J (ALV-J) infection. Next, we found that ALV-J CHN06 strain infection of DF-1 cells correlated with extracellular signal-regulated kinase 2 (ERK2) activation, which was mainly induced within 15 min, a very early stage of infection, and at a late infection stage, from 108 h to 132 h post-infection. Infection with other ALV subgroup (A/B) strains also triggered ERK/MAPK activation. Moreover, when activating ERK2, ALV subgroups A, B and J simultaneously induced the phosphorylation of c-Jun, an AP1 family member and p38 activation but had no obvious effect on JNK activation at either 15 min or 120 h. Interestingly, only PD98059 inhibited the ALV-induced c-Jun phosphorylation while SP600125 or SB203580 had no influence on c-Jun activation. Furthermore, the viral gp85 and gag proteins were found to contribute to ERK2/AP1 activation. Additionally, the specific ERK inhibitor, PD980509, significantly suppressed ALV replication, as evidenced by extremely low levels of ALV promoter activity and ALV-J protein expression. In vivo analysis of ERK2 activation in tumor cells derived from ALV-J-infected chicken demonstrated a strong correlation between ERK/MAPK activation and virus-associated tumorigenesis. PMID:26754177

  4. Schnitzler syndrome: heterogeneous immunopathological findings involving IgM-skin interactions.

    PubMed

    Lipsker, D; Spehner, D; Drillien, R; Schmitt, P; Cribier, B; Heid, E; Humbel, R L; Grosshans, E

    2000-05-01

    The Schnitzler syndrome is the association of chronic urticaria, intermittent fever, osteosclerotic bone lesions and a monoclonal IgM gammopathy. It is not yet firmly established whether the monoclonal immunoglobulin component plays a part in the pathophysiology of the urticarial lesions. Immunoblotting on epidermal and dermal human skin extracts as well as immunoelectron microscopic (IEM) studies on Lowicryl K4M-embedded skin sections were performed in three patients with the Schnitzler syndrome. Western blotting on epidermal extracts showed the presence of IgM-kappa antiskin autoantibodies in two patients. These antibodies displayed the same isotype as the monoclonal components and recognized a 280-290-kDa antigen in one patient and a 200-kDa antigen in the other patient. IEM studies showed sparse IgM deposits in the epidermis, around the keratinocytes, near the desmosomes in one patient and dense deposits below the lamina densa, in the region of the anchoring fibrils, in another patient. Antiskin IgM autoantibodies of the same isotype as their monoclonal gammopathies can be present in the serum of some patients with the Schnitzler syndrome. These IgM antibodies seem to deposit in vivo in the epidermis and at the dermal-epidermal junction, in the region of the anchoring fibrils. These findings suggest that the monoclonal gammopathy plays a part in the pathophysiology of the skin rash. They also suggest patient heterogeneity both in the skin antigens that are recognized as well as in their localization. PMID:10809854

  5. Inflammation and Cell Death in Age-Related Macular Degeneration: An Immunopathological and Ultrastructural Model.

    PubMed

    Ardeljan, Christopher P; Ardeljan, Daniel; Abu-Asab, Mones; Chan, Chi-Chao

    2014-01-01

    The etiology of Age-related Macular Degeneration (AMD) remains elusive despite the characterization of many factors contributing to the disease in its late-stage phenotypes. AMD features an immune system in flux, as shown by changes in macrophage polarization with age, expression of cytokines and complement, microglial accumulation with age, etc. These point to an allostatic overload, possibly due to a breakdown in self vs. non-self when endogenous compounds and structures acquire the appearance of non-self over time. The result is inflammation and inflammation-mediated cell death. While it is clear that these processes ultimately result in degeneration of retinal pigment epithelium and photoreceptor, the prevalent type of cell death contributing to the various phenotypes is unknown. Both molecular studies as well as ultrastructural pathology suggest pyroptosis, and perhaps necroptosis, are the predominant mechanisms of cell death at play, with only minimal evidence for apoptosis. Herein, we attempt to reconcile those factors identified by experimental AMD models and integrate these data with pathology observed under the electron microscope-particularly observations of mitochondrial dysfunction, DNA leakage, autophagy, and cell death. PMID:25580276

  6. Immunopathological diagnosis of cicatricial pemphigoid with desquamative gingivitis. A case report.

    PubMed

    Kurihara, M; Nishimura, F; Hashimoto, T; Komai, A; Ueda, H; Kokeguchi, S; Takashiba, S; Murayama, Y

    2001-02-01

    Cicatricial pemphigoid (CP) is a chronic subepidermal bullous dermatosis which primarily involves the mucous membranes. The oral cavity and the eye are most frequently involved. Since extension of the lesion into the pharynx and esophagus causes sore throat and dysphagia and progressive ocular lesions may cause blindness, early and valid diagnosis is very important. Here we present a case of cicatricial pemphigoid with onset at age 45 in a patient who manifested severe periodontal disease and showed the lesion on the mucous membranes of the mouth (desquamative gingivitis), skin, and eyes. Since definite diagnosis is very important, we describe how we made a differential diagnosis from other diseases which also accompany desquamative gingivitis. We examined the clinical manifestations, blood test results, HLA-genotype, histopathologic findings of the affected tissue, and immunological findings in relation to autoimmunity. Since many of the CP cases are first referred to periodontists or dentists, we believe that the diagnostic strategy described in the present study will be quite informative for making rapid and definite diagnoses of similar cases. PMID:11288799

  7. Antigen presenting cells in situ: their identification and involvement in immunopathology.

    PubMed Central

    Poulter, L W

    1983-01-01

    Macrophages and other dendritic non-lymphoid cells have been shown to be functionally capable of presenting antigen to induce lymphocyte responses. These cells can now be studied in situ and distinguished, one from another, within normal tissues and sites of cellular infiltration. Analysis of the microenvironment within which these cells are found can be made with immunohistological methods using monoclonal antibodies (McAbs) and cytochemical techniques. In some cases McAbs are specific for particular types of antigen presenting cell. Using such reagents, evidence is accumulating that these cells may be intimately involved in the pathogenesis of immunoregulatory disorders. What is now required is a more definitive correlation between functional capacity and cell phenotype established with cells isolated from blood, and from normal and pathological tissues. If this is possible the immunopathologist may be able, not only to analyse complex microenvironments but also directly determine the interactions and mechanisms at play within the diseased tissues. PMID:6352095

  8. The Influence of Sex Steroid Hormones in the Immunopathology of Experimental Pulmonary Tuberculosis

    PubMed Central

    Bini, Estela Isabel; Mata Espinosa, Dulce; Marquina Castillo, Brenda; Barrios Payán, Jorge; Colucci, Darío; Cruz, Alejandro Francisco; Zatarain, Zyanya Lucía; Alfonseca, Edgar; Pardo, Marta Romano; Bottasso, Oscar; Pando, Rogelio Hernández

    2014-01-01

    The relation between men and women suffering pulmonary tuberculosis is 7/3 in favor to males. Sex hormones could be a significant factor for this difference, considering that testosterone impairs macrophage activation and pro-inflammatory cytokines production, while estrogens are proinflammatory mediator’s inducer. The aim of this work was to compare the evolution of tuberculosis in male and female mice using a model of progressive disease. BALB/c mice, male and female were randomized into two groups: castrated or sham-operated, and infected by the intratracheal route with a high dose of Mycobacterium tuberculosis strain H37Rv. Mice were euthanized at different time points and in their lungs were determined bacilli loads, inflammation, cytokines expression, survival and testosterone levels in serum. Non-castrated male mice showed significant higher mortality and bacilli burdens during late disease than female and castrated male animals. Compared to males, females and castrated males exhibited significant higher inflammation in all lung compartments, earlier formation of granulomas and pneumonia, while between castrated and non-castrated females there were not significant differences. Females and castrated males expressed significant higher TNF-α, IFN γ, IL12, iNOS and IL17 than non-castrated males during the first month of infection. Serum Testosterone of males showed higher concentration during late infection. Orchidectomy at day 60 post-infection produced a significant decrease of bacilli burdens in coexistence with higher expression of TNFα, IL-12 and IFNγ. Thus, male mice are more susceptible to tuberculosis than females and this was prevented by castration suggesting that testosterone could be a tuberculosis susceptibility factor. PMID:24722144

  9. Dual roles of endogenous and exogenous galectin-1 in the control of testicular immunopathology

    PubMed Central

    Pérez, Cecilia V.; Gómez, Leticia G.; Gualdoni, Gisela S.; Lustig, Livia; Rabinovich, Gabriel A.; Guazzone, Vanesa A.

    2015-01-01

    Galectin-1 (Gal-1), a proto-type member of galectin family, is highly expressed in immune privileged sites, including the testis. However, in spite of considerable progress the relevance of endogenous and exogenous Gal-1 in testis pathophysiology have not yet been explored. Here we evaluated the in vivo roles of Gal-1 in experimental autoimmune orchitis (EAO), a well-established model of autoimmune testicular inflammation associated with subfertility and infertility. A significant reduction in the incidence and severity of EAO was observed in mice genetically deficient in Gal-1 (Lgals1−/−) versus wild-type (WT) mice. Testicular histopathology revealed the presence of multifocal testicular damage in WT mice characterized by an interstitial mononuclear cell infiltrate and different degrees of germ cell sloughing of seminiferous tubules. TUNEL assay and assessment of active caspase-3 expression, revealed the prevalence of apoptotic spermatocytes mainly localized in the adluminal compartment of seminiferous tubules in EAO mice. A significant increased number of TUNEL-positive germ cells was detected in EAO testis from WT compared with Lgals1−/− mice. In contrast, exogenous administration of recombinant Gal-1 to WT mice undergoing EAO attenuated the severity of the disease. Our results unveil a dual role of endogenous versus exogenous Gal-1 in the control of autoimmune testis inflammation. PMID:26223819

  10. SPECIAL ISSUE VETERINARY IMMUNOLOGY IMMUNOPATHOLOGY: PROCEEDINGS 8TH INTERNATIONAL VETERINARY IMMUNOLOGY SYMPOSIUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is the Special Issue of Vet. Immunol. Immunopathol. that summarizes the 8th International Veterinary Immunology Symposium (8 th IVIS) held August 15th-19th, 2007, in Ouro Preto, Brazil. The 8 th IVIS highlighted the importance of veterinary immunology for animal health, vaccinology, reproducti...

  11. Immunopathology of glomerulonephritis associated with chronic woodchuck hepatitis virus infection in woodchucks (Marmota monax).

    PubMed Central

    Peters, D. N.; Steinberg, H.; Anderson, W. I.; Hornbuckle, W. E.; Cote, P. J.; Gerin, J. L.; Lewis, R. M.; Tennant, B. C.

    1992-01-01

    Retrospective analysis of necropsy findings of 705 woodchucks was performed to determine the prevalence and morphology of immune-mediated glomerulonephritis, its relationship to woodchuck hepatitis virus (WHV) infection, and the presence of major WHV antigens. Twenty-six woodchucks had glomerular lesions. Renal tissue of the 26 animals was evaluated histologically and immunohistochemically for immune-mediated glomerulonephritis. Of these 26 animals, immune-mediated glomerulonephritis was diagnosed in six, all of which were chronic WHV carriers. Membranous glomerulonephritis was identified in three animals, two of which also had mesangial proliferation. Host immunoglobulin was present within the mesangium and along capillary loops in all three. Woodchuck hepatitis virus core antigen (WHcAg) was present along capillary loops of two of these animals, one membranous and one mixed, and in the mesangium of all three. Woodchuck hepatitis virus surface antigen (WHsAg) deposition was similar to WHcAg deposition but was only present along capillaries in those animals with mixed nephritis. The remaining three animals had mesangial proliferation. WHsAg and host immunoglobulin deposition were predominately mesangial; WHcAg was not detected. Transmission electron microscopy showed thickening of the capillary loop basement membranes and subepithelial electron-dense deposits in animal one, and deposits in the mesangium in animal six. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:1632459

  12. Serology of Lupus Erythematosus: Correlation between Immunopathological Features and Clinical Aspects.

    PubMed

    Cozzani, Emanuele; Drosera, Massimo; Gasparini, Giulia; Parodi, Aurora

    2014-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the aberrant production of a broad and heterogenous group of autoantibodies. Even though the presence of autoantibodies in SLE has been known, for more than 60 years, still nowadays a great effort is being made to understand the pathogenetic, diagnostic, and prognostic meaning of such autoantibodies. Antibodies to ds-DNA are useful for the diagnosis of SLE, to monitor the disease activity, and correlate with renal and central nervous involvements. Anti-Sm antibodies are highly specific for SLE. Anti-nucleosome antibodies are an excellent marker for SLE and good predictors of flares in quiescent lupus. Anti-histone antibodies characterize drug-induced lupus, while anti-SSA/Ro and anti-SSB/La antibodies are associated with neonatal lupus erythematosus and photosensitivity. Anti-ribosomal P antibodies play a role in neuropsychiatric lupus, but their association with clinical manifestations is still unclear. Anti-phospholipid antibodies are associated with the anti-phospholipid syndrome, cerebral vascular disease, and neuropsychiatric lupus. Anti-C1q antibodies amplify glomerular injury, and the elevation of their titers may predict renal flares. Anti-RNP antibodies are a marker of Sharp's syndrome but can be found in SLE as well. Anti-PCNA antibodies are present in 5-10% of SLE patients especially those with arthritis and hypocomplementemia. PMID:24649358

  13. A novel immunopathological association of IgG4-RD and vasculitis with Hashimoto's thyroiditis

    PubMed Central

    Minamino, Hiroto; Ariyasu, Hiroyuki; Furuta, Hiroto; Nishi, Masahiro; Yoshimasu, Takashi; Nishikawa, Akinori; Nakanishi, Masanori; Tsuchihashi, Shigeki; Kojima, Fumiyoshi; Murata, Shin-ichi; Inoue, Gen; Akamizu, Takashi

    2016-01-01

    Summary A 73-year-old man with Hashimoto's thyroiditis (HT) suffered from purpura on the lower legs. He was diagnosed with IgG4-related disease (IgG4-RD) with serum IgG4 elevation and dacryo-sialadenitis confirmed histologically. Serum Th2 and Treg cytokines, interleukin 7 (IL7), IL8 and Th2 chemokine levels were elevated, while skewed Th1 balance was seen in fluorescence-activated cell sorting (FACS). Therefore, preferential Th1 balance in HT appeared to be followed by IgG4-RD characterized with Th2 and Treg polarization. The commencement of steroid therapy dramatically exacerbated clinical manifestations including IgG4-RD-associated HT. The measurement of cytokine and chemokine levels as well as FACS analysis in the development of IgG4-RD seemed to be beneficial. In conclusion, an innovative association of HT, IgG4-RD and vasculitis was observed. This report also offers novel diagnostic and therapeutic approaches for IgG4-RD. Learning points Recently, a subtype of HT has been considered to be a thyroid manifestation of IgG4-RD, although the etiology of IgG4-RD is not established yet. Immunologically a close association between HT and vasculitis was reported. Leukocytoclastic vasculitis is a rare skin presentation of IgG4-RD. In the current case, during the course of HT, IgG4-RD and leukocytoclastic vasculitis occurred; thus, innate immunity and acquired immunity seem to be involved in the development of IgG4-RD. The measurement of cytokine and chemokines appeared to be beneficial in the development of IgG4-RD. Remarkably, effectiveness of steroid therapy for HT suggested presence of IgG4-RD-associated HT. Therefore, this report highlights the pathogenesis of IgG4-RD and proposes novel therapeutic mechanisms. Clinicians should pay attention to the development of IgG4-RD and vasculitis during long course of HT. PMID:26966543

  14. The Battle Against Immunopathology: Infectious Tolerance Mediated by Regulatory T Cells

    PubMed Central

    Gravano, David M.; Vignali, Dario A.A.

    2012-01-01

    Infectious tolerance is a process whereby one regulatory lymphoid population confers suppressive capacity on another. Diverse immune responses are induced following infection or inflammatory insult that can protect the host, or potentially cause damage if not properly controlled. Thus, the process of infectious tolerance may be critical in vivo for exerting effective immune control and maintaining immune homeostasis by generating specialized regulatory subpopulations with distinct mechanistic capabilities. Foxp3+ regulatory T cells (Tregs) are a central mediator of infectious tolerance through their ability to convert conventional T cells into induced regulatory T cells (iTregs) directly by secretion of the suppressive cytokines TGF-β, IL-10 or IL-35, or indirectly via dendritic cells. In this review we will discuss the mechanisms and cell populations that mediate and contribute to infectious tolerance, with a focus on the intestinal environment, where tolerance induction to foreign material is critical. PMID:22205213

  15. MicroRNAs in the Host-Apicomplexan Parasites Interactions: A Review of Immunopathological Aspects

    PubMed Central

    Judice, Carla C.; Bourgard, Catarina; Kayano, Ana C. A. V.; Albrecht, Letusa; Costa, Fabio T. M.

    2016-01-01

    MicroRNAs (miRNAs), a class of small non-coding regulatory RNAs, have been detected in a variety of organisms ranging from ancient unicellular eukaryotes to mammals. They have been associated with numerous molecular mechanisms involving developmental, physiological and pathological changes of cells and tissues. Despite the fact that miRNA-silencing mechanisms appear to be absent in some Apicomplexan species, an increasing number of studies have reported a role for miRNAs in host-parasite interactions. Host miRNA expression can change following parasite infection and the consequences can lead, for instance, to parasite clearance. In this context, the immune system signaling appears to have a crucial role. PMID:26870701

  16. Immunopathology of RSV infection: prospects for developing vaccines without this complication.

    PubMed

    van Drunen Littel-van den Hurk, S; Mapletoft, J W; Arsic, N; Kovacs-Nolan, J

    2007-01-01

    Respiratory syncytial virus is the most important cause of lower respiratory tract infection in infants and young children. RSV clinical disease varies from rhinitis and otitis media to bronchiolitis and pneumonia. An increased incidence of asthma later in life has been associated with the more severe lower respiratory tract infections. Despite its importance as a pathogen, there is no licensed vaccine against RSV. This is due to a number of factors complicating the development of an effective and safe vaccine. The immunity to natural RSV infection is incomplete as re-infections occur in all age groups, which makes it challenging to design a protective vaccine. Second, the primary target population is the newborn infant, which has a relatively immature immune system and maternal antibodies that can interfere with vaccination. Finally, some vaccines have resulted in a predisposition for exacerbated pulmonary disease in infants, which was attributed to an imbalanced Th2-biased immune response, although the exact cause has not been elucidated. This makes it difficult to proceed with vaccine testing in infants. It is likely that an effective and safe vaccine needs to elicit a balanced immune response, including RSV-specific neutralising antibodies, CD8 T-cells, Th1/Th2 CD4 T-cells and preferably secretory IgA. Subunit vaccines formulated with appropriate adjuvants may be adequate for previously exposed individuals. However, intranasally delivered genetically engineered attenuated or vectored vaccines are currently most promising for newborns, as they are expected to induce a balanced immune response similar to that elicited to natural infection and not be subject to interference from maternal antibodies. Maternal vaccination may be the optimal strategy to protect the very young infants. PMID:17004293

  17. Role of innate immune cells and their products in lung immunopathology.

    PubMed

    Suzuki, Tomoko; Chow, Chung-Wai; Downey, Gregory P

    2008-01-01

    The lung, with its enormous surface area, is literally 'bathed in a sea' of potential toxins that include pathogenic microorganisms, allergens, and pollutants. To preserve homeostasis and protect itself from injury, the lung has evolved intricate defense systems that guard it from these injurious agents. This chapter will focus on the innate component of the immune system that represents the first line of defense against microbial pathogens and pollutants. The innate immune system of the lung is diverse and includes structural cells such as epithelial cells and fibroblasts as well as itinerant leukocytes such as neutrophils, monocytes, and macrophages. Dendritic cells and mast cells, although of hematopoietic origin, are resident in the lung and help sense and orchestrate immune responses in the lung. Cells of the innate immune system secrete various soluble factors that are directly or indirectly microbicidal and/or modulate the inflammatory response. Among these soluble factors, proteinases and anti-proteinases factor prominently and exert both physiological and pathological effects on the function of diverse cell types in the lung. In concert with the adaptive immune system, the innate immune system of the lung is highly effective in combating invading microbial pathogens as evidenced by the rarity with which healthy humans succumb to lung infections. PMID:18272422

  18. Immunopathological assessments of human Blastocystis spp. in experimentally infected immunocompetent and immunosuppresed mice.

    PubMed

    Abdel-Hafeez, Ekhlas H; Ahmad, Azza K; Abdelgelil, Noha H; Abdellatif, Manal Z M; Kamal, Amany M; Hassanin, Kamel M A; Abdel-Razik, Abdel-Razik H; Abdel-Raheem, Ehab M

    2016-05-01

    Blastocystis spp., one of the most common parasites colonizing the human intestine, is an extracellular, luminal protozoan with controversial pathogenesis. The host's immune response against Blastocystis spp. infection has also not been defined yet. Therefore, this research aimed to assess the potential pathogenicity of this parasite and its ability to modulate the immune response in experimental infected immunocompetent and immunosuppresed mice. These results demonstrated that the infected immunosuppressed mice were more affected than infected immunocompetent mice. Histopathological examination of the small intestine in the infected immunosuppressed mice showed that Blastocystis spp. infiltrated all the layers. Moreover, the epithelia showed exfoliation and inflammatory cell infiltration in submucosa compared to that of the infected immunocompetent mice. As well, examination of the large intestine of the infected immunosuppressed group showed severe goblet cell hyperplasia. Blastocystis spp. infiltrated all the large intestine layers compared to that of the infected immunocompetent group. Furthermore, there was a significant upregulation of the expression of proinflammatory cytokines: interleukin 12 (IL-12) and tumor necrosis factor alpha (TNF-α) in the infected immunosuppressed mice compared to that of the infected immunocompetent ones (p ≤ 0.004 and p ≤ 0.002, respectively). However, the expression of anti-inflammatory cytokines (IL-4 and IL-10) was significantly downregulated in the infected immunosuppressed group compared to that of the infected immunocompetent group one at 10 days postinfection (p ≤ 0.002 and p ≤ 0.001, respectively). The results of this study revealed that Blastocystis spp. affected the production of pro- and anti-inflammatory cytokines in both groups of mice compared to healthy normal (naive) group. Additionally, these data showed that there was a significant upregulation (p ≤ 0.005) of the locally synthesized antibody: secretary IgA (sIgA) in the gut of the infected immunocompetent mice when compared to that of the infected immunosuppressed ones. PMID:26860840

  19. Increased mortality and AIDS-like immunopathology in wild chimpanzees infected with SIVcpz.

    PubMed

    Keele, Brandon F; Jones, James Holland; Terio, Karen A; Estes, Jacob D; Rudicell, Rebecca S; Wilson, Michael L; Li, Yingying; Learn, Gerald H; Beasley, T Mark; Schumacher-Stankey, Joann; Wroblewski, Emily; Mosser, Anna; Raphael, Jane; Kamenya, Shadrack; Lonsdorf, Elizabeth V; Travis, Dominic A; Mlengeya, Titus; Kinsel, Michael J; Else, James G; Silvestri, Guido; Goodall, Jane; Sharp, Paul M; Shaw, George M; Pusey, Anne E; Hahn, Beatrice H

    2009-07-23

    African primates are naturally infected with over 40 different simian immunodeficiency viruses (SIVs), two of which have crossed the species barrier and generated human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2). Unlike the human viruses, however, SIVs do not generally cause acquired immunodeficiency syndrome (AIDS) in their natural hosts. Here we show that SIVcpz, the immediate precursor of HIV-1, is pathogenic in free-ranging chimpanzees. By following 94 members of two habituated chimpanzee communities in Gombe National Park, Tanzania, for over 9 years, we found a 10- to 16-fold higher age-corrected death hazard for SIVcpz-infected (n = 17) compared to uninfected (n = 77) chimpanzees. We also found that SIVcpz-infected females were less likely to give birth and had a higher infant mortality rate than uninfected females. Immunohistochemistry and in situ hybridization of post-mortem spleen and lymph node samples from three infected and two uninfected chimpanzees revealed significant CD4(+) T-cell depletion in all infected individuals, with evidence of high viral replication and extensive follicular dendritic cell virus trapping in one of them. One female, who died within 3 years of acquiring SIVcpz, had histopathological findings consistent with end-stage AIDS. These results indicate that SIVcpz, like HIV-1, is associated with progressive CD4(+) T-cell loss, lymphatic tissue destruction and premature death. These findings challenge the prevailing view that all natural SIV infections are non-pathogenic and suggest that SIVcpz has a substantial negative impact on the health, reproduction and lifespan of chimpanzees in the wild. PMID:19626114

  20. Relationship between the characteristics of immunopathological expression of hepatitis C virus antigen and hepatocytic injury.

    PubMed

    Sun, Y; Gao, S L; Hao, L J; Li, L; Gu, B; Ding, Q Y; Lu, P J; Xiong, H Y; Li, Y X

    1993-10-01

    Biopsied liver tissues from 352 cases were tested for hepatitis C virus (HCVAg) with improved PAP immunohistologic chemical method. Furthermore, corresponding seroantibody to hepatitis C virus was also tested. The total HCVAg positive rate was 9.1%. The HCVAg positive rate in chronic persistent hepatitis (CPH) was 5%. The HCVAg positive rate in chronic active hepatitis (CAH) was 11.2%. The HCVAg positive rate raised gradually along with the severity of hepatocytic injury. HCVAg may be seen in necrotic liver cells exfoliating into the liver sinus, indicating a close relationship between HCVAg and hepatocytic injury. Expression of HCVAg was mostly of the nucleus type in CPH cases and was mostly of the plasma type in CAH cases. The periphery of nucleus type-expressed positive cells generally had no marked inflammatory cell infiltration. The periphery of plasma type-expressed positive cells had a certain amount of inflammatory cell infiltration. Along with the severity of hepatocytic injury, HCVAg expressed itself in a positive correlation according to the nucleus and plasma types. The HCVAg positive cells were located mostly in the lobular peripheral band and rarely located in the venoperipheral band. It was possible that this had some relation with the lobular microcirculation of blood and blood supply. In this study, there was no obvious correlation between the HCVAg positive rate in hepatic tissues and the anti-HCV positive rate in sera. Neither the patients with HCVAg positive liver tissues nor the patients with seropositive anti-HCV had any history of blood transfusion and the use of blood products.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7518373

  1. Immunopathologic effects of scorpion venom on hepato-renal tissues: Involvement of lipid derived inflammatory mediators.

    PubMed

    Lamraoui, Amal; Adi-Bessalem, Sonia; Laraba-Djebari, Fatima

    2015-10-01

    Scorpion venoms are known to cause different inflammatory disorders through complex mechanisms in various tissues. In the study here, the involvement of phospholipase A2 (PLA2) and cyclo-oxygenase (COX)-derived metabolites in hepatic and renal inflammation responses were examined. Mice were envenomed with Androctonus australis hector scorpion venom in the absence or presence of inhibitors that can interfere with lipid inflammatory mediator synthesis, i.e., dexamethasone (PLA2 inhibitor), indomethacin (non-selective COX-1/COX-2 inhibitor), or celecoxib (selective COX-2 inhibitor). The inflammatory response was assessed by evaluating vascular permeability changes, inflammatory cell infiltration, oxidative/nitrosative stress marker levels, and by histologic and functional analyses of the liver and kidney. Results revealed that the venom alone induced an inflammatory response in this tissues marked by increased microvascular permeability and inflammatory cell infiltration, increases in levels of nitric oxide and lipid peroxidation, and decreases in antioxidant defense. Moreover, significant alterations in the histological architecture of these organs were associated with increased serum levels of some metabolic enzymes, as well as urea and uric acid. Pre-treatment of mice with dexamethasone led to significant decreases of the inflammatory disorders in the hepatic parenchyma; celecoxib pre-treatment seemed to be more effective against renal inflammation. Indomethacin pre-treatment only slightly reduced the inflammatory disorders in the tissues. These results suggest that the induced inflammation response in liver was mediated mainly by PLA2 activation, while the renal inflammatory process was mediated by prostaglandin formation by COX-2. These findings provide additional insight toward the understanding of activated pathways and related mechanisms involved in scorpion envenoming syndrome. PMID:26231296

  2. Clinical, anatomic, and immunopathologic characterization of Babesia gibsoni infection in the domestic dog (Canis familiaris).

    PubMed

    Wozniak, E J; Barr, B C; Thomford, J W; Yamane, I; McDonough, S P; Moore, P F; Naydan, D; Robinson, T W; Conrad, P A

    1997-08-01

    The pathology associated with acute, chronic, and recrudescent Babesia gibsoni infections was characterized in a group of 6 naturally or experimentally infected, spleen-intact and splenectomized dogs. All experimentally infected dogs became acutely parasitemic, lethargic, anemic, thrombocytopenic, and hemoglobinuric. Anatomic lesions associated, with the disease included diffuse nonsuppurative periportal and centrilobular hepatitis, multifocal necrotizing arteritis, membranoproliferative glomerulonephritis, reactive lymphadenopathy, diffuse erythrophagocytosis, and extramedullary hematopoiesis. The density of CD3+ lymphocytes within the liver sinusoids was markedly increased. Aggregates of large mononuclear cells with immunohistochemical features of activated macrophages were demonstrated in the central veins of the liver. Kupffer cells throughout the hepatic sinusoids appeared hypertrophic and prominent. The density of sinusoidal T lymphocytes, macrophages in central veins, and the degree of Kupffer cell hypertrophy were greatest in the splenectomized dogs. Multifocal deposits of IgM antibody were immunohistochemically demonstrated within the walls of inflamed arteries and renal glomeruli. The results of this study suggest that intense immunostimulation resulting in activation and expansion of T and B lymphocyte populations, macrophage recruitment and activation, vasculitis, glomerulonephritis and anemia contribute to the pathology associated with B. gibsoni infections. PMID:9267413

  3. Modulatory activity of Lactobacillus rhamnosus OLL2838 in a mouse model of intestinal immunopathology.

    PubMed

    Ogita, Tasuku; Bergamo, Paolo; Maurano, Francesco; D'Arienzo, Rossana; Mazzarella, Giuseppe; Bozzella, Giuseppina; Luongo, Diomira; Sashihara, Toshihiro; Suzuki, Takuya; Tanabe, Soichi; Rossi, Mauro

    2015-06-01

    Gut microbiota and probiotic strains play an important role in oral tolerance by modulating regulatory and effector cell components of the immune system. We have previously described the ability of Lactobacilli to influence both the innate and adaptive immunity to wheat gluten, a food antigen, in mouse. In this study, we further explored the immunomodulatory mechanisms elicited in this model by testing three specific probiotic strains, namely L. rhamnosus OLL2838, B. infantis ATCC15697 and S. thermophilus Sfi39. In vitro analysis showed the all tested strains induced maturation of bone marrow derived dendritic cells (DCs). However, only L. rhamnosus induced appreciable levels of IL-10 and nitric oxide productions, whereas S. thermophilus essentially elicited IL-12 and TNF-α. The anti-inflammatory ability of OLL2838 was then tested in vivo by adopting mice that develop a gluten-specific enteropathy. This model is characterized by villus blunting, crypt hyperplasia, high levels of intestinal IFN-γ, increased cell apoptosis in lamina propria, and reduced intestinal total glutathione (GSHtot) and glutathione S-transferase (GST) activity. We found that, following administration of OLL2838, GSHtot and GST activity were enhanced, whereas caspase-3 activity was reduced. On the contrary, this probiotic strain failed in recovering the normal histology and further increased intestinal IFN-γ. Confocal microscopy revealed the inability of the probiotic strain to appropriately interact with enterocytes of the small intestine and with Peyer's patches in treated mice. In conclusion, these data highlighted the potential of L. rhamnosus OLL2838 to recover specific toxicity parameters induced by gluten in enteropathic mice through mechanisms that involve induction of low levels of reactive oxygen species (ROS). PMID:25623030

  4. Immunopathology features of chronic rhinosinusitis in high-altitude dwelling Tibetans.

    PubMed

    Luo, Ba; Feng, Liu; Jintao, Du; Yafeng, Liu; Shixi, Liu; Nan, Zhang; Bachert, Claus

    2013-01-01

    Chronic rhinosinusitis (CRS) presents distinct inflammatory and remodeling patterns in different populations and environments. Tibetan ethnic groups live at high altitudes and in cold weather conditions. We sought to examine whether Tibetans exhibit distinct CRS pathology or characteristics. Sinonasal polyps and mucosal tissue were obtained from 14 Tibetan patients with CRS and nasal polyps (CRSwNPs), 13 patients with CRS without nasal polyps (CRSsNPs), and 12 Tibetan controls. Tissue homogenates and serum samples were assayed for several T-helper (TH) cell cytokines and mediators using enzyme linked immunosorbent assay profiles were measured using quantity polymerase chain reaction. Several key inflammatory cells were examined for immunohistochemical markers. CRSwNPs were characterized by increased mediator promoting eosinophilic inflammation (interleukin [IL]-5, eosinophil cationic protein, and total immunoglobulin E) and slight synergism with expression of IL-8, IL-2sRa, IL-1beta, IL-6, and myeloperoxidase, and a predominance of eosinophils, mast cells, and neutrophils. GATA-3 transcription factor was significantly increased and Foxp3 showed a tendency to be impaired in CRSwNPs compared with controls. CRSsNPs were characterized by significantly high levels of transforming growth factor beta1, increased interferon γ, and a significant enhancement of Foxp3 and T-beta compared with CRSwNPs. There were reduced numbers of inflammatory cells but increased levels of macrophages in CRSsNPs. Compared with CRSsNPs, CRSwNPs present a severe inflammatory reaction and show a TH2 milieu with apparently impaired regulatory T cells (Treg) function and increased inflammatory cells infiltration predominated by eosinophilic and mast cells. In contrast, TH1 polarization with enhanced Treg function and increased levels of macrophages appear in CRSsNPs. PMID:24124640

  5. The host immune response in respiratory virus infection: balancing virus clearance and immunopathology.

    PubMed

    Newton, Amy H; Cardani, Amber; Braciale, Thomas J

    2016-07-01

    The respiratory tract is constantly exposed to the external environment, and therefore, must be equipped to respond to and eliminate pathogens. Viral clearance and resolution of infection requires a complex, multi-faceted response initiated by resident respiratory tract cells and innate immune cells and ultimately resolved by adaptive immune cells. Although an effective immune response to eliminate viral pathogens is essential, a prolonged or exaggerated response can damage the respiratory tract. Immune-mediated pulmonary damage is manifested clinically in a variety of ways depending on location and extent of injury. Thus, the antiviral immune response represents a balancing act between the elimination of virus and immune-mediated pulmonary injury. In this review, we highlight major components of the host response to acute viral infection and their role in contributing to mitigating respiratory damage. We also briefly describe common clinical manifestations of respiratory viral infection and morphological correlates. The continuing threat posed by pandemic influenza as well as the emergence of novel respiratory viruses also capable of producing severe acute lung injury such as SARS-CoV, MERS-CoV, and enterovirus D68, highlights the need for an understanding of the immune mechanisms that contribute to virus elimination and immune-mediated injury. PMID:26965109

  6. Programmed death 1 protects from fatal circulatory failure during systemic virus infection of mice.

    PubMed

    Frebel, Helge; Nindl, Veronika; Schuepbach, Reto A; Braunschweiler, Thomas; Richter, Kirsten; Vogel, Johannes; Wagner, Carsten A; Loffing-Cueni, Dominique; Kurrer, Michael; Ludewig, Burkhard; Oxenius, Annette

    2012-12-17

    The inhibitory programmed death 1 (PD-1)-programmed death ligand 1 (PD-L1) pathway contributes to the functional down-regulation of T cell responses during persistent systemic and local virus infections. The blockade of PD-1-PD-L1-mediated inhibition is considered as a therapeutic approach to reinvigorate antiviral T cell responses. Yet previous studies reported that PD-L1-deficient mice develop fatal pathology during early systemic lymphocytic choriomeningitis virus (LCMV) infection, suggesting a host protective role of T cell down-regulation. As the exact mechanisms of pathology development remained unclear, we set out to delineate in detail the underlying pathogenesis. Mice deficient in PD-1-PD-L1 signaling or lacking PD-1 signaling in CD8 T cells succumbed to fatal CD8 T cell-mediated immunopathology early after systemic LCMV infection. In the absence of regulation via PD-1, CD8 T cells killed infected vascular endothelial cells via perforin-mediated cytolysis, thereby severely compromising vascular integrity. This resulted in systemic vascular leakage and a consequential collapse of the circulatory system. Our results indicate that the PD-1-PD-L1 pathway protects the vascular system from severe CD8 T cell-mediated damage during early systemic LCMV infection, highlighting a pivotal physiological role of T cell down-regulation and suggesting the potential development of immunopathological side effects when interfering with the PD-1-PD-L1 pathway during systemic virus infections. PMID:23230000

  7. Immunoactivation induced by chronic viral infection inhibits viral replication and drives immunosuppression through sustained IFN-I responses.

    PubMed

    Honke, Nadine; Shaabani, Namir; Merches, Katja; Gassa, Asmae; Kraft, Anke; Ehrhardt, Katrin; Häussinger, Dieter; Löhning, Max; Dittmer, Ulf; Hengel, Hartmut; Recher, Mike; Lang, Philipp A; Lang, Karl S

    2016-02-01

    Acute or chronic viral infections can lead to generalized immunosuppression. Several mechanisms, such as immunopathology of CD8(+) T cells, inhibitory receptors, or regulatory T (Treg) cells, contribute to immune dysfunction. Moreover, patients with chronic viral infections usually do not respond to vaccination, a finding that has not been previously explained. Recently, we reported that CD169(+) macrophages enforce viral replication, which is essential for guaranteeing antigen synthesis and efficient adaptive immune responses. In the present study, we used a chronic lymphocytic choriomeningitis virus infection mouse model to determine whether this mechanism is affected by chronic viral infection, which may impair the activation of adaptive immunity. We found that enforced viral replication of a superinfecting virus is completely blunted in chronically infected mice. This absence of enforced viral replication in CD169(+) macrophages is not explained by CD8(+) T-cell-mediated immunopathology but rather by prolonged IFN-I responses. Consequently, the absence of viral replication impairs both antigen production and the adaptive immune response against the superinfecting virus. These findings indicate that chronic infection leads to sustained IFN-I action, which is responsible for the absence of an antiviral immune response against a secondary viral infection. PMID:26507703

  8. Virus-induced gene silencing of soybean rust resistance genes in Glycine tomentella

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean rust, incited by the fungal pathogen Phakopsora pachyrhizi, is a serious foliar soybean disease capable of causing major economic yield loss. Specific resistance to P. pachyrhizi is known and single dominant genes have been identified in soybean (Rpp1-4), but these genes have been deemed ine...

  9. Efficacy of various Marek's disease vaccines protocols for prevention of Marek's disease virus-induced immunosuppression.

    PubMed

    Faiz, Nik M; Cortes, Aneg L; Guy, James S; Fogle, Jonathan E; Gimeno, Isabel M

    2016-07-29

    Marek's disease virus (MDV) induces tumors and severe immunosuppression in chickens. MDV-induced immunosuppression (MDV-IS) is very complex and difficult to study. In particular, the late MDV-IS (late-MDV-IS) is of great concern since it can occur in the absence of lymphoid organ atrophy or gross tumors. We have recently developed a model to reproduce late-MDV-IS under laboratory conditions. This model measures MDV-IS indirectly by assessing the effect of MDV infection on the efficacy of infectious laryngotracheitis (ILT) vaccination; hence the name late-MDV-IS ILT model. In this study, we have used the late-MDV-IS ILT model to evaluate if MD vaccination can protect against late-MDV-IS. One experiment was conducted to determine whether serotype 1 MD vaccines (CVI988 and Md5ΔMEQ) could induce late-MDV-IS by themselves. Three additional experiments were conducted to evaluate efficacy of different MD vaccines (HVT, HVT+SB-1, CVI988, and Md5ΔMEQ) and different vaccine protocols (day-old vaccination, in ovo vaccination, and double vaccination) against late-MDV-IS. Our results show that none of the currently used vaccine protocols (HVT, HVT+SB-1, or CVI988 administered at day of age, in ovo, or in double vaccination protocols) protected against late-MDV-IS induced by vv+MDV strains 648A and 686. Experimental vaccine Md5ΔMEQ administered subcutaneously at one day of age was the only vaccine protocol that significantly reduced late-MDV-IS induced by vv+MDV strain 686. This study demonstrates that currently used vaccine protocols confer high levels of protection against MDV-induced tumors (protection index=100), but do not protect against late-MDV-IS; thus, commercial poultry flocks could suffer late-MDV-IS even in complete absence of tumors. Our results suggest that MDV-IS might not be related to the development of tumors and novel control methods are needed. Further evaluation of the experimental vaccine Md5ΔMEQ might shed light on protective mechanisms against late-MDV-IS. PMID:27371103

  10. Mumps Virus Induces Protein-Kinase-R-Dependent Stress Granules, Partly Suppressing Type III Interferon Production.

    PubMed

    Hashimoto, Shin; Yamamoto, Soh; Ogasawara, Noriko; Sato, Toyotaka; Yamamoto, Keisuke; Katoh, Hiroshi; Kubota, Toru; Shiraishi, Tsukasa; Kojima, Takashi; Himi, Tetsuo; Tsutsumi, Hiroyuki; Yokota, Shin-Ichi

    2016-01-01

    Stress granules (SGs) are cytoplasmic granular aggregations that are induced by cellular stress, including viral infection. SGs have opposing antiviral and proviral roles, which depend on virus species. The exact function of SGs during viral infection is not fully understood. Here, we showed that mumps virus (MuV) induced SGs depending on activation of protein kinase R (PKR). MuV infection strongly induced interferon (IFN)-λ1, 2 and 3, and IFN-β through activation of IFN regulatory factor 3 (IRF3) via retinoic acid inducible gene-I (RIG-I) and the mitochondrial antiviral signaling (MAVS) pathway. MuV-induced IFNs were strongly upregulated in PKR-knockdown cells. MuV-induced SG formation was suppressed by knockdown of PKR and SG marker proteins, Ras-GTPase-activating protein SH3-domain-binding protein 1 and T-cell-restricted intracellular antigen-1, and significantly increased the levels of MuV-induced IFN-λ1. However, viral titer was not altered by suppression of SG formation. PKR was required for induction of SGs by MuV infection and regulated type III IFN (IFN-λ1) mRNA stability. MuV-induced SGs partly suppressed type III IFN production by MuV; however, the limited suppression was not sufficient to inhibit MuV replication in cell culture. Our results provide insight into the relationship between SGs and IFN production induced by MuV infection. PMID:27560627

  11. Resistance to geminivirus infection by virus-induced expression of dianthin in transgenic plants.

    PubMed

    Hong, Y; Saunders, K; Hartley, M R; Stanley, J

    1996-06-01

    Ribosome-inactivating proteins (RIPs) are naturally occurring plant toxins that exhibit antiviral activity against a diverse range of plant and animal viruses. Here, the action of dianthin, a potent RIP isolated from Dianthus caryophyllus, has been exploited to engineer resistance to a plant DNA virus, African cassava mosaic virus (ACMV), in transgenic Nicotiana benthamiana. To achieve this, dianthin has been expressed from the ACMV virion-sense promoter that is transactivated by the product of viral gene AC2. This avoids the need for constitutive expression of the RIP, facilitating the regeneration of phenotypically normal plants, and ensures transgene expression is localized to virus-infected cells. When challenged with ACMV, transgenic plants produce atypical necrotic lesions on inoculated leaves, indicative of dianthin expression, viral DNA accumulation is significantly reduced in these tissues, and plants exhibit attenuated systemic symptoms from which they recover. This phenotype holds for isolates of ACMV but not for other geminiviruses, suggesting that AC2 homologues from the latter are unable to efficiently transactivate the ACMV promoter. PMID:8659104

  12. Protection against polyoma virus-induced tumors is perforin-independent

    SciTech Connect

    Byers, Anthony M.; Hadley, Annette; Lukacher, Aron E. . E-mail: alukach@emory.edu

    2007-02-20

    CD8 T cells are necessary for controlling tumors induced by mouse polyoma virus (PyV), but the effector mechanism(s) responsible have not been determined. We examined the PyV tumorigenicity in C57BL/6 mice mutated in Fas or carrying targeted disruptions in the perforin gene or in both TNF receptor type I and type II genes. Surprisingly, none of these mice developed tumors. Perforin/Fas double-deficient radiation bone marrow chimeric mice were also resistant to PyV-induced tumors. Anti-PyV CD8 T cells in perforin-deficient mice were found not to differ from wild type mice with respect to phenotype, capacity to produce cytokines or maintenance of memory T cells, indicating that perforin does not modulate the PyV-specific CD8 T cell response. In addition, virus was cleared and persisted to similar extents in wild type and perforin-deficient mice. In summary, perforin/granzyme exocytosis is not an essential effector pathway for protection against PyV infection or tumorigenesis.

  13. Co-expression analysis of differentially expressed genes in hepatitis C virus-induced hepatocellular carcinoma.

    PubMed

    Song, Qingfeng; Zhao, Chang; Ou, Shengqiu; Meng, Zhibin; Kang, Ping; Fan, Liwei; Qi, Feng; Ma, Yilong

    2015-01-01

    The aim of the current study was to investigate the molecular mechanisms underlying hepatitis C virus (HCV)-induced hepatocellular carcinoma (HCC) using the expression profiles of HCV-infected Huh7 cells at different time points. The differentially expressed genes (DEGs) were identified with the Samr package in R software once the data were normalized. Functional and pathway enrichment analysis of the identified DEGs was also performed. Subsequently, MCODE in Cytoscape software was applied to conduct module analysis of the constructed co-expression networks. A total of 1,100 DEGs were identified between the HCV-infected and control samples at 12, 18, 24 and 48 h post-infection. DEGs at 24 and 48 h were involved in the same signaling pathways and biological processes, including sterol biosynthetic processes and tRNA amino-acylation. There were 22 time series genes which were clustered into 3 expression patterns, and the demarcation point of the 2 expression patterns that 401 overlapping DEGs at 24 and 48 h clustered into was 24 h post-infection. tRNA synthesis-related biological processes emerged at 24 and 48 h. Replication and assembly of HCV in HCV-infected Huh7 cells occurred mainly at 24 h post-infection. In view of this, the screened time series genes have the potential to become candidate target molecules for monitoring, diagnosing and treating HCV-induced HCC. PMID:25339452

  14. [Varicella zoster virus-induced meningoencephalitis complicated with orbital apex syndrome: a case report].

    PubMed

    Wakida, Kenji; Sakurai, Takeo; Nishida, Hiroshi

    2014-09-01

    A 69-year-old male was admitted to hospital with clouded consciousness and abnormal behavior. His body temperature was 38.2 degree Celsius upon admission and he was somnolent. Herpes zoster was observed along the first division of the trigeminal nerve on the right side of the face. The right palpebra was severely swollen, and the right eye showed a dilated pupil, loss of light reflex, and total ophthalmoplegia. A spinal tap revealed pleocytosis and increased proteins, and a DNA-PCR test for varicella-zoster virus (VZV) was positive. Optic neuritis was diagnosed based on fundoscopy. Following acyclovir administration, the patient regained full consciousness and the rash was alleviated; however, visual acuity did not recover. VZV-induced meningoencephalitis complicated with orbital apex syndrome is rarely observed. We suspect that VZV initially infected the nasociliary nerve at the distal end of the first division of trigeminal nerve and spread to the adjacent optic, oculomotor, trochlear, and abducens nerves, resulting in VZV-induced meningoencephalitis complicated with orbital apex syndrome. PMID:25200582

  15. Cyclophilin A as a New Therapeutic Target for Hepatitis C Virus-induced Hepatocellular Carcinoma

    PubMed Central

    2013-01-01

    Hepatocellular carcinoma (HCC) related to hepatitis B virus (HBV) and hepatitis C virus (HCV) infections is thought to account for more than 80% of primary liver cancers. Both HBV and HCV can establish chronic liver inflammatory infections, altering hepatocyte and liver physiology with potential liver disease progression and HCC development. Cyclophilin A (CypA) has been identified as an essential host factor for the HCV replication by physically interacting with the HCV non structural protein NS5A that in turn interacts with RNA-dependent RNA polymerase NS5B. CypA, a cytosolic binding protein of the immunosuppressive drug cyclosporine A, is overexpressed in many cancer types and often associated with malignant transformation. Therefore, CypA can be a good target for molecular cancer therapy. Because of antiviral activity, the CypA inhibitors have been tested for the treatment of chronic hepatitis C. Nonimmunosuppressive Cyp inhibitors such as NIM811, SCY-635, and Alisporivir have attracted more interests for appropriating CypA for antiviral chemotherapeutic target on HCV infection. This review describes CypA inhibitors as a potential HCC treatment tool that is contrived by their obstructing chronic HCV infection and summarizes roles of CypA in cancer development. PMID:24227937

  16. Hepatitis B virus-induced calreticulin protein is involved in IFN resistance.

    PubMed

    Yue, Xin; Wang, Hui; Zhao, Fanpeng; Liu, Shi; Wu, Jianguo; Ren, Wendan; Zhu, Ying

    2012-07-01

    IFN-α is a widely used treatment for hepatitis B virus (HBV) infection, and IFN resistance caused by viral and/or host factors is currently a challenging clinical problem. A better understanding of the molecular mechanisms underlying IFN immunotherapy in the treatment of viral infection would be very beneficial clinically and is of immense clinical importance. Calreticulin (CRT) is an endoplasmic reticulum luminal calcium-binding chaperone that is involved in the regulation of calcium homoeostasis, the folding of newly synthesized proteins, and many other cellular functions. However, little is known about the role of CRT in HBV infection. In this study, we observed high levels of CRT expression in the sera and PBMCs of patients with HBV relative to those of healthy individuals. HBV upregulated the expression of CRT at the transcriptional level. Further investigation showed that HBV-induced CRT enhanced HBV replication by antagonizing the IFN pathway. CRT suppressed the production of endogenous IFN-α by reducing the nuclear translocation of IFN regulatory factor-7 but not IFN regulatory factor-3. Furthermore, CRT also suppressed the antiviral activity of IFN-α by inhibiting the phosphorylation of STAT1 and decreasing the expression of two IFN-α downstream effectors, protein kinase R and 2',5'-oligoadenylate synthetase. Our results offer new insights into the pathogenesis of HBV infection and may provide potential targets for anti-HBV therapy. PMID:22661095

  17. Rapid Determination of Gene Function by Virus-induced Gene Silencing in Wheat and Barley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cereal crops are essential components to the human and animal food supply. Solutions to many of the problems challenging cereal production will require identification of genes responsible for particular traits. Unfortunately, the process of identifying gene function is very slow and complex in...

  18. Vaccinia Virus Induces Rapid Necrosis in Keratinocytes by a STAT3-Dependent Mechanism

    PubMed Central

    He, Yong; Fisher, Robert; Chowdhury, Soma; Sultana, Ishrat; Pereira, Claudia P.; Bray, Mike; Reed, Jennifer L.

    2014-01-01

    Rationale Humans with a dominant negative mutation in STAT3 are susceptible to severe skin infections, suggesting an essential role for STAT3 signaling in defense against cutaneous pathogens. Methods To focus on innate antiviral defenses in keratinocytes, we used a standard model of cutaneous infection of severe combined immunodeficient mice with the current smallpox vaccine, ACAM-2000. In parallel, early events post-infection with the smallpox vaccine ACAM-2000 were investigated in cultured keratinocytes of human and mouse origin. Results Mice treated topically with a STAT3 inhibitor (Stattic) developed larger vaccinia lesions with higher virus titers and died more rapidly than untreated controls. Cultured human and murine keratinocytes infected with ACAM-2000 underwent rapid necrosis, but when treated with Stattic or with inhibitors of RIP1 kinase or caspase-1, they survived longer, produced higher titers of virus, and showed reduced activation of type I interferon responses and inflammatory cytokines release. Treatment with inhibitors of RIP1 kinase and STAT3, but not caspase-1, also reduced the inflammatory response of keratinocytes to TLR ligands. Vaccinia growth properties in Vero cells, which are known to be defective in some antiviral responses, were unaffected by inhibition of RIP1K, caspase-1, or STAT3. Conclusions Our findings indicate that keratinocytes suppress the replication and spread of vaccinia virus by undergoing rapid programmed cell death, in a process requiring STAT3. These data offer a new framework for understanding susceptibility to skin infection in patients with STAT3 mutations. Interventions which promote prompt necroptosis/pyroptosis of infected keratinocytes may reduce risks associated with vaccination with live vaccinia virus. PMID:25419841

  19. Virus-induced atherosclerosis. Herpesvirus infection alters aortic cholesterol metabolism and accumulation.

    PubMed Central

    Hajjar, D. P.; Fabricant, C. G.; Minick, C. R.; Fabricant, J.

    1986-01-01

    Infection of normocholesterolemic, specific-pathogen-free chickens with Marek's disease herpesvirus (MDV) has been shown histologically to lead to chronic atherosclerosis like that in humans. The development of herpesvirus-induced atherosclerosis in vivo and the presence of specific Marek's antigen within aortic cells suggested that MDV infection may modify lipid metabolism and lead to significant lipid accumulation. Experiments reported herein were designed to determine the types and quantity of lipid present in aortas from MDV-infected and uninfected chickens between 2 and 8 months of age following infection and assess one possible mechanism of lipid accumulation by evaluating the effect of MDV infection on aortic cholesterol and cholesteryl ester (CE) metabolism. Chromatographic-fluorometric analyses indicated that at 4 and 8 months of age after MDV inoculation, MDV-infected animals had a significant (P less than 0.05) two-fold to threefold increase in total aortic lipid accumulation characterized by significant increases in cholesterol, CE, triacylglycerol, and phospholipid as compared with aortas from uninfected animals. At 8 months of age, similar increases in aortic lipid accumulation were observed in MDV-infected animals as compared with those animals vaccinated with turkey herpesvirus and later challenged with MDV. CE synthetic activity was increased significantly by 50% at 4 months of age in the MDV-infected group as compared with the uninfected group, which could explain the initial increase in CE accumulation. By 8 months of age, the authors also observed a twofold increase in CE synthetic activity and a 30% and 80% reduction in lysosomal and cytoplasmic CE hydrolytic activities, respectively, in aortas of MDV-infected chickens as compared to controls. Moreover, infection with MDV blocked the activation of cytoplasmic CE hydrolytic activity by dibutyryl cyclic AMP or exogenous cyclic AMP-dependent protein kinase. Taken together, these results suggest that lipid accretion in aortas of MDV-infected chickens results, in part, from alterations in cholesterol/CE metabolism during early stages of the disease. These findings support the hypothesis that human atherosclerosis may result from specific herpesvirus infection which can alter lipid metabolism and lead to lipid accretion. PMID:2934987

  20. A generic screening platform for inhibitors of virus induced cell fusion using cellular electrical impedance.

    PubMed

    Watterson, Daniel; Robinson, Jodie; Chappell, Keith J; Butler, Mark S; Edwards, David J; Fry, Scott R; Bermingham, Imogen M; Cooper, Matthew A; Young, Paul R

    2016-01-01

    Fusion of the viral envelope with host cell membranes is an essential step in the life cycle of all enveloped viruses. Despite such a clear target for antiviral drug development, few anti-fusion drugs have progressed to market. One significant hurdle is the absence of a generic, high-throughput, reproducible fusion assay. Here we report that real time, label-free measurement of cellular electrical impedance can quantify cell-cell fusion mediated by either individually expressed recombinant viral fusion proteins, or native virus infection. We validated this approach for all three classes of viral fusion and demonstrated utility in quantifying fusion inhibition using antibodies and small molecule inhibitors specific for dengue virus and respiratory syncytial virus. PMID:26976324

  1. Primary polyoma virus-induced murine thymic epithelial tumors. A tumor model of thymus physiology.

    PubMed Central

    Hoot, G. P.; Kettman, J. R.

    1989-01-01

    Thymic tumors were induced in C3'/Bittner mice by neonatal inoculation with polyoma virus. The objective of this study was to identify the phenotypes of the cells within the tumors and to attempt to determine the origin of the neoplastic cell population(s). At the ultrastructural level, the neoplastic cells resembled normal thymic epithelium with tonofilaments and desmosomes. Immunoperoxidase staining demonstrated the presence of cytokeratin, Iak, -beta 2-microglobulin, -asialo-GM1, the thymic cortical epithelial marker ER-TR4, and the medullary epithelial marker ER-TR5. Islands of normal cortical thymocytes supported by residual normal cortical epithelium and acid phosphatase-positive cortical macrophages were interspersed in the tumors. Residual islands of normal medullary architecture with nonspecific esterase-positive IDCs were rarely identified in tumors. Most lymphocytes in the tumors were normal immature cortical thymocytes with the phenotype Tdt+, PNA+, Thy 1.2bright, Ly-1dull, H-2Kkdull, ThB+, J11d+, and Lyt-2+L3T4+. Lymphocytes in the tumors were steroid-sensitive like normal thymocytes. The proportions of Lyt-2+L3T4- and Lyt-2-L3T4+ cells were generally larger in the tumors than in normal thymus and reflected the higher frequency of lymphocytes in the tumors capable of proliferating in vitro in response to Con A plus IL-2. The data were consistent with the hypothesis that the neoplasia originates from thymic epithelium that is interspersed with normal, developing thymic lymphocytes. Images Figure 4 p[688]-a Figure 1 Figure 2 Figure 3 p687-a Figure 7 PMID:2552813

  2. Basic Research on Virus-Induced Asthma Exacerbation: Inhibition of Inflammatory Chemokine Expression by Fluticasone Propionate

    PubMed Central

    Matsukura, Satoshi; Kurokawa, Masatsugu; Homma, Tetsuya; Watanabe, Shin; Suzuki, Shintaro; Ieki, Koushi; Takeuchi, Hiroko; Notomi, Kyoko; Schleimer, Robert P.; Kawaguchi, Mio; Kokubu, Fumio

    2016-01-01

    Background Viral infection can exacerbate asthma by inducing the accumulation of inflammatory cells in the airway. We have previously reported that double-stranded RNA (dsRNA), a viral product and ligand of the Toll-like receptor-3 (TLR3), activates the transcription factors NF-κB and IRF-3 and upregulates the expression of inflammatory chemokines in airway epithelial cells. Here, we examined the effects of the glucocorticoid fluticasone propionate (FP) on the expression of the inflammatory chemokines CCL5, CXCL8 and CXCL10. Methods The airway epithelial cell line BEAS-2B was used for this study. Expression of CCL5, CXCL8 and CXCL10 mRNA and protein was quantified by real-time PCR and ELISA assay, respectively. To examine the association of FP with the physiology of chemokine production, we included several methods. Nuclear translocation of transcription factors was determined by performing Western blot analysis. Histone deacetylase (HDAC) activity in nuclear extracts was measured using a colorimetric assay. Stability of the chemokine mRNAs was examined in cells incubated with actinomycin D. The activities of the CCL5 promoter and the transcription factors NF-κB and IRF-3 were assessed using luciferase reporter assays. Results Treatment of BEAS-2B cells with FP significantly and dose-dependently (10−9 to 10−6 M) inhibited dsRNA-induced expression of CCL5, CXCL8 and CXCL10 protein and mRNA, but did not affect mRNA stability. FP also significantly inhibited dsRNA-stimulated CCL5 promoter activity. However, FP had no effect on the activity of HDAC or the nuclear translocation of NF-κB and IRF-3. Conclusions FP inhibits the dsRNA-stimulated expression of inflammatory chemokines in airway epithelial cells. FP may act by inhibiting chemokine transcription through an as yet Unidentified mechanism. PMID:23711858

  3. IRES-Dependent Translational Control during Virus-Induced Endoplasmic Reticulum Stress and Apoptosis

    PubMed Central

    Hanson, Paul J.; Zhang, Huifang M.; Hemida, Maged Gomaa; Ye, Xin; Qiu, Ye; Yang, Decheng

    2012-01-01

    Many virus infections and stresses can induce endoplasmic reticulum (ER) stress response, a host self-defense mechanism against viral invasion and stress. During this event, viral and cellular gene expression is actively regulated and often encounters a switching of the translation initiation from cap-dependent to internal ribosome-entry sites (IRES)-dependent. This switching is largely dependent on the mRNA structure of the 5′ untranslated region (5′ UTR) and on the particular stress stimuli. Picornaviruses and some other viruses contain IRESs within their 5′ UTR of viral genome and employ an IRES-driven mechanism for translation initiation. Recently, a growing number of cellular genes involved in growth control, cell cycle progression and apoptosis were also found to contain one or more IRES within their long highly structured 5′ UTRs. These genes initiate translation usually by a cap-dependent mechanism under normal physiological conditions; however, in certain environments, such as infection, starvation, and heat shock they shift translation initiation to an IRES-dependent modality. Although the molecular mechanism is not entirely understood, a number of studies have revealed that several cellular biochemical processes are responsible for the switching of translation initiation to IRES-dependent. These include the cleavage of translation initiation factors by viral and/or host proteases, phosphorylation (inactivation) of host factors for translation initiation, overproduction of homologous proteins of cap-binding protein eukaryotic initiation factors (eIF)4E, suppression of cap-binding protein eIF4E expression by specific microRNA, activation of enzymes for mRNA decapping, as well as others. Here, we summarize the recent advances in our understanding of the molecular mechanisms for the switching of translation initiation, particularly for the proteins involved in cell survival and apoptosis in the ER stress pathways during viral infections. PMID:22461781

  4. Neutrophil Extracellular Traps Enhance Early Inflammatory Response in Sendai Virus-Induced Asthma Phenotype.

    PubMed

    Akk, Antonina; Springer, Luke E; Pham, Christine T N

    2016-01-01

    Paramyxoviral infection in childhood has been linked to a significant increased rate of asthma development. In mice, paramyxoviral infection with the mouse parainfluenza virus type I, Sendai virus (Sev), causes a limited bronchiolitis followed by persistent asthma traits. We have previously shown that the absence of cysteine protease dipeptidyl peptidase I (DPPI) dampened the acute lung inflammatory response and the subsequent asthma phenotype induced by Sev. Adoptive transfer of wild-type neutrophils into DPPI-deficient mice restored leukocyte influx, the acute cytokine response, and the subsequent mucous cell metaplasia that accompanied Sev-induced asthma phenotype. However, the exact mechanism by which DPPI-sufficient neutrophils promote asthma development following Sev infection is still unknown. We hypothesize that neutrophils recruited to the alveolar space following Sev infection elaborate neutrophil extracellular traps (NETs) that propagate the inflammatory cascade, culminating in the eventual asthma phenotype. Indeed, we found that Sev infection was associated with NET formation in the lung and release of cell-free DNA complexed to myeloperoxidase in the alveolar space and plasma that peaked on day 2 post infection. Absence of DPPI significantly attenuated Sev-induced NET formation in vivo and in vitro. Furthermore, concomitant administration of DNase 1, which dismantled NETs, or inhibition of peptidylarginine deiminase 4 (PAD4), an essential mediator of NET formation, suppressed the early inflammatory responses to Sev infection. Lastly, NETs primed bone marrow-derived cells to release cytokines that can amplify the inflammatory cascade. PMID:27617014

  5. Impaired cellular energy metabolism contributes to bluetongue-virus-induced autophagy.

    PubMed

    Lv, Shuang; Xu, Qingyuan; Sun, Encheng; Zhang, Jikai; Wu, Donglai

    2016-10-01

    Bluetongue virus (BTV) has been found to trigger autophagy to favor its replication, but the underlying mechanisms have not been clarified. Here, we show that cellular energy metabolism is involved in BTV-induced autophagy. Cellular ATP synthesis was impaired by BTV1 infection, causing metabolic stress, which was responsible for activation of autophagy, since the conversion of LC3 and aggregation of GFP-LC3 (autophagy markers) were suppressed when infection-caused energy depletion was reversed via MP (metabolic substrate) treatment. The reduced virus yields with MP further supported this view. Overall, our findings suggest that BTV1-induced disruption of cellular energy metabolism contributes to autophagy, and this provides new insights into BTV-host interactions. PMID:27379971

  6. Neutrophil Extracellular Traps Enhance Early Inflammatory Response in Sendai Virus-Induced Asthma Phenotype

    PubMed Central

    Akk, Antonina; Springer, Luke E.; Pham, Christine T. N.

    2016-01-01

    Paramyxoviral infection in childhood has been linked to a significant increased rate of asthma development. In mice, paramyxoviral infection with the mouse parainfluenza virus type I, Sendai virus (Sev), causes a limited bronchiolitis followed by persistent asthma traits. We have previously shown that the absence of cysteine protease dipeptidyl peptidase I (DPPI) dampened the acute lung inflammatory response and the subsequent asthma phenotype induced by Sev. Adoptive transfer of wild-type neutrophils into DPPI-deficient mice restored leukocyte influx, the acute cytokine response, and the subsequent mucous cell metaplasia that accompanied Sev-induced asthma phenotype. However, the exact mechanism by which DPPI-sufficient neutrophils promote asthma development following Sev infection is still unknown. We hypothesize that neutrophils recruited to the alveolar space following Sev infection elaborate neutrophil extracellular traps (NETs) that propagate the inflammatory cascade, culminating in the eventual asthma phenotype. Indeed, we found that Sev infection was associated with NET formation in the lung and release of cell-free DNA complexed to myeloperoxidase in the alveolar space and plasma that peaked on day 2 post infection. Absence of DPPI significantly attenuated Sev-induced NET formation in vivo and in vitro. Furthermore, concomitant administration of DNase 1, which dismantled NETs, or inhibition of peptidylarginine deiminase 4 (PAD4), an essential mediator of NET formation, suppressed the early inflammatory responses to Sev infection. Lastly, NETs primed bone marrow-derived cells to release cytokines that can amplify the inflammatory cascade.

  7. Direct antiviral agent treatment of decompensated hepatitis C virus-induced liver cirrhosis

    PubMed Central

    Ohkoshi, Shogo; Hirono, Haruka; Yamagiwa, Satoshi

    2015-01-01

    Recently, direct antiviral agents (DAAs) have been increasingly used for the treatment of chronic hepatitis C virus (HCV) infections, replacing interferon-based regimens that have severe adverse effects and low tolerability. The constant supply of new DAAs makes shorter treatment periods with enhanced safety possible. The efficacy of DAAs for treatment of compensated liver cirrhosis (LC) is not less than that for treatment of non-cirrhotic conditions. These clinical advantages have been useful in pre- and post-liver transplantation (LT) settings. Moreover, DAAs can be used to treat decompensated HCV-induced LC in elderly patients or those with severe complications otherwise having poor prognosis. Although encouraging clinical data are beginning to appear, the actual efficacy of DAAs for suppressing disease progression, allowing delisting for LT and, most importantly, improving prognosis of patients with decompensated HCV-LC remains unknown. Case-control studies to examine the short- or long-term effects of DAAs for treatment of decompensated HCV-LC are urgently need. PMID:26558145

  8. Murine viral hepatitis involves NK cell depletion associated with virus-induced apoptosis

    PubMed Central

    LEHOUX, M; JACQUES, A; LUSIGNAN, S; LAMONTAGNE, L

    2004-01-01

    Mouse hepatitis virus type 3 (MHV3), a coronavirus, is an excellent animal model for the study of immunological disorders related to acute and chronic hepatitis. In this study, we have verified if the fulminant hepatitis induced by MHV3 could be related to an impairment of innate immunity. Groups of three C57BL/6 mice were infected with the pathogenic L2-MHV3 or attenuated YAC-MHV3 viruses, and the natural killer (NK) cell populations from liver, spleen and bone marrow were analysed. The percentage of intrahepatic NK1·1+T cell receptor (TCR)− cells did not increase while NK1·1+TCRinter cells decreased in both L2-MHV3- and YAC-MHV3-infected mice. Concurrently, splenic and myeloid NK1·1+ cells decreased in L2-MHV3-infected mice. However, the cytotoxic activity of NK cells increased in liver and decreased in bone marrow from pathogenic L2-MHV3-infected mice while no modification was detected in YAC-MHV3-infected mice. Flow cytometric analysis revealed that both normal and larger splenic or myeloid NK cells decreased more in pathogenic L2-MHV3-infected mice than in attenuated YAC-MHV3-infected mice. In vitro viral infections of interleukin (IL)-15-stimulated lymphoid cells from liver and bone marrow revealed that L2-MHV3 induced higher decreases in cell viability of NK1·1+ cells than the YAC-MHV3 variant. The NK cell decreases were due to the viral permissivity leading to cytopathic effects characterized by cell rounding, syncytia formation and apoptosis. Larger NK+ syncytia were observed in L2-MHV3-infected cells than in YAC-MHV3-infected cells. These results suggest that NK cell production is impaired by viral infection favouring fulminant hepatitis. PMID:15196242

  9. Knockdown of specific host factors protects against influenza virus-induced cell death

    PubMed Central

    Tran, A T; Rahim, M N; Ranadheera, C; Kroeker, A; Cortens, J P; Opanubi, K J; Wilkins, J A; Coombs, K M

    2013-01-01

    Cell death is a characteristic consequence of cellular infection by influenza virus. Mounting evidence indicates the critical involvement of host-mediated cellular death pathways in promoting efficient influenza virus replication. Furthermore, it appears that many signaling pathways, such as NF-κB, formerly suspected to solely promote cell survival, can also be manipulated to induce cell death. Current understanding of the cell death pathways involved in influenza virus-mediated cytopathology and in virus replication is limited. This study was designed to identify host genes that are required for influenza-induced cell death. The approach was to perform genome-wide lentiviral-mediated human gene silencing in A549 cells and determine which genes could be silenced to provide resistance to influenza-induced cell death. The assay proved to be highly reproducible with 138 genes being identified in independent screens. The results were independently validated using siRNA to each of these candidates. Graded protection was observed in this screen with the silencing of any of 19 genes, each providing >85% protection. Three gene products, TNFSF13 (APRIL), TNFSF12-TNFSF13 (TWE-PRIL) and USP47, were selected because of the high levels of protection conferred by their silencing. Protein and mRNA silencing and protection from influenza-induced cell death was confirmed using multiple shRNA clones and siRNA, indicating the specificity of the effects. USP47 knockdown prevented proper viral entry into the host cell, whereas TNFSF12-13/TNFSF13 knockdown blocked a late stage in viral replication. This screening approach offers the means to identify a large number of potential candidates for the analysis of viral-induced cell death. These results may also have much broader applicability in defining regulatory mechanisms involved in cell survival. PMID:23949218

  10. Disruption of Rpp1-mediated soybean rust resistance by virus-induced gene silencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean rust is a fungus that causes disease on soybeans. The discovery of soybean genes and proteins that are important for disease resistance to soybean rust may help improve soybean cultivars through breeding or transgenic technology. Proteins previously discovered in the cell nucleus of soybea...

  11. The adeno-associated virus rep gene suppresses herpes simplex virus-induced DNA amplification.

    PubMed Central

    Heilbronn, R; Bürkle, A; Stephan, S; zur Hausen, H

    1990-01-01

    Herpes simplex virus (HSV) induces within the host cell genome DNA amplification which can be suppressed by coinfection with adeno-associated virus (AAV). To characterize the AAV functions mediating this effect, cloned AAV type 2 wild-type or mutant genomes were transfected into simian virus 40 (SV40)-transformed hamster cells together with the six HSV replication genes (encoding UL5, UL8, major DNA-binding protein, DNA polymerase, UL42, and UL52) which together are necessary and sufficient for the induction of SV40 DNA amplification (R. Heilbronn and H. zur Hausen, J. Virol. 63:3683-3692, 1989). The AAV rep gene was identified as being responsible for the complete inhibition of HSV-induced SV40 DNA amplification. Likewise, rep inhibited origin-dependent HSV replication. rep neither killed the transfected host cells nor interfered with gene expression from the cotransfected amplification genes. This points to a specific interference with HSV-induced DNA amplification. Images PMID:2159559

  12. Virus induced gene silencing of a gene repressing flowering in sugar beet.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposure to a prolonged cold period during winter is necessary for flowering in the next spring in many biennial plants - a process termed vernalization. We have described BvFL1, a vernalization gene in sugar beet (Beta vulgaris), which is a repressor of flowering that is downregulated in response ...

  13. A complement-microglial axis drives synapse loss during virus-induced memory impairment.

    PubMed

    Vasek, Michael J; Garber, Charise; Dorsey, Denise; Durrant, Douglas M; Bollman, Bryan; Soung, Allison; Yu, Jinsheng; Perez-Torres, Carlos; Frouin, Arnaud; Wilton, Daniel K; Funk, Kristen; DeMasters, Bette K; Jiang, Xiaoping; Bowen, James R; Mennerick, Steven; Robinson, John K; Garbow, Joel R; Tyler, Kenneth L; Suthar, Mehul S; Schmidt, Robert E; Stevens, Beth; Klein, Robyn S

    2016-06-23

    Over 50% of patients who survive neuroinvasive infection with West Nile virus (WNV) exhibit chronic cognitive sequelae. Although thousands of cases of WNV-mediated memory dysfunction accrue annually, the mechanisms responsible for these impairments are unknown. The classical complement cascade, a key component of innate immune pathogen defence, mediates synaptic pruning by microglia during early postnatal development. Here we show that viral infection of adult hippocampal neurons induces complement-mediated elimination of presynaptic terminals in a murine WNV neuroinvasive disease model. Inoculation of WNV-NS5-E218A, a WNV with a mutant NS5(E218A) protein leads to survival rates and cognitive dysfunction that mirror human WNV neuroinvasive disease. WNV-NS5-E218A-recovered mice (recovery defined as survival after acute infection) display impaired spatial learning and persistence of phagocytic microglia without loss of hippocampal neurons or volume. Hippocampi from WNV-NS5-E218A-recovered mice with poor spatial learning show increased expression of genes that drive synaptic remodelling by microglia via complement. C1QA was upregulated and localized to microglia, infected neurons and presynaptic terminals during WNV neuroinvasive disease. Murine and human WNV neuroinvasive disease post-mortem samples exhibit loss of hippocampal CA3 presynaptic terminals, and murine studies revealed microglial engulfment of presynaptic terminals during acute infection and after recovery. Mice with fewer microglia (Il34(-/-) mice with a deficiency in IL-34 production) or deficiency in complement C3 or C3a receptor were protected from WNV-induced synaptic terminal loss. Our study provides a new murine model of WNV-induced spatial memory impairment, and identifies a potential mechanism underlying neurocognitive impairment in patients recovering from WNV neuroinvasive disease. PMID:27337340

  14. Even transcriptionally competent proviruses are silent in bovine leukemia virus-induced sheep tumor cells.

    PubMed Central

    Van den Broeke, A; Cleuter, Y; Chen, G; Portetelle, D; Mammerickx, M; Zagury, D; Fouchard, M; Coulombel, L; Kettmann, R; Burny, A

    1988-01-01

    To investigate the role of proviral integration and expression in cellular transformation induced by bovine leukemia virus (BLV), three BLV-induced tumors harboring a single proviral copy were selected upon restriction and hybridization analysis. Tumors 344 and 395 were shown to contain a full-size proviral copy, whereas in tumor 1345 the provirus appeared to be heavily deleted. RNA gel blot hybridization with an antisense RNA probe showed no transcription of the viral sequences in the fresh tumors or in sheep tumor cells growing in vitro. The proviruses were cloned and transfected in mammalian cell lines. Transient-expression experiments revealed that the complete proviruses were still able to express the trans-activating protein (Tat) as well as structural proteins, demonstrating that the nonexpression of a provirus in a tumor cell does not necessarily imply a structural alteration of the viral information. In contrast, sequence analysis of the provirus with a large deletion and transient-expression assays proved that this truncated provirus, isolated from a tumor, was unable to code for viral proteins. These data indicate that expression of viral genes, including tat, is not required for the maintenance of the transformed state. Images PMID:2848258

  15. Co-expression analysis of differentially expressed genes in hepatitis C virus-induced hepatocellular carcinoma

    PubMed Central

    SONG, QINGFENG; ZHAO, CHANG; OU, SHENGQIU; MENG, ZHIBIN; KANG, PING; FAN, LIWEI; QI, FENG; MA, YILONG

    2015-01-01

    The aim of the current study was to investigate the molecular mechanisms underlying hepatitis C virus (HCV)-induced hepatocellular carcinoma (HCC) using the expression profiles of HCV-infected Huh7 cells at different time points. The differentially expressed genes (DEGs) were identified with the Samr package in R software once the data were normalized. Functional and pathway enrichment analysis of the identified DEGs was also performed. Subsequently, MCODE in Cytoscape software was applied to conduct module analysis of the constructed co-expression networks. A total of 1,100 DEGs were identified between the HCV-infected and control samples at 12, 18, 24 and 48 h post-infection. DEGs at 24 and 48 h were involved in the same signaling pathways and biological processes, including sterol biosynthetic processes and tRNA amino-acylation. There were 22 time series genes which were clustered into 3 expression patterns, and the demarcation point of the 2 expression patterns that 401 overlapping DEGs at 24 and 48 h clustered into was 24 h post-infection. tRNA synthesis-related biological processes emerged at 24 and 48 h. Replication and assembly of HCV in HCV-infected Huh7 cells occurred mainly at 24 h post-infection. In view of this, the screened time series genes have the potential to become candidate target molecules for monitoring, diagnosing and treating HCV-induced HCC. PMID:25339452

  16. Rabies virus-induced apoptosis involves caspase-dependent and caspase-independent pathways.

    PubMed

    Sarmento, Luciana; Tseggai, Tesfai; Dhingra, Vikas; Fu, Zhen F

    2006-11-01

    Previously, it has been shown that the laboratory attenuated rabies virus CVS-B2C, but not the wild-type virus SHBRV, induces apoptosis in mice and the induction of apoptosis is mediated by viral glycoprotein. Induction of apoptosis by CVS-B2C limits the spread of the virus in the CNS. In the present study, we characterized the pathways by which CVS-B2C induces apoptosis. BSR cells were infected with CVS-B2C or SHBRV and harvested at different time points for detection of apoptosis by immunofluorescence and flow cytometry. Apoptosis was detected only in cells infected with CVS-B2C, but not SHBRV. Caspase activity and expression of several apoptotic proteins were analyzed by fluorometric assay and Western blotting. Activation of caspase-8 and -3, but not of caspase-9, was observed in CVS-B2C-infected cells. In addition, the level of expression of Apaf-1 did not change. Furthermore, PARP was cleaved confirming activation of downstream caspases. All these data suggest that CVS-B2C infection activates the extrinsic, but not the intrinsic, apoptotic pathway. In addition, AIF, a caspase-independent apoptotic protein was up-regulated and translocated from the cytoplasm to the nucleus post-infection, suggesting that apoptosis induced by CVS-B2C also involves the activation of a caspase-independent pathway. PMID:16814422

  17. Models of Respiratory Infections: Virus-Induced Asthma Exacerbations and Beyond

    PubMed Central

    Saturni, Sara; Contoli, Marco; Spanevello, Antonio

    2015-01-01

    Respiratory infections are one of the main health problems worldwide. They are a challenging field of study due to an intricate relationship between the pathogenicity of microbes and the host's defenses. To better understand mechanisms of respiratory infections, different models have been developed. A model is the reproduction of a disease in a system that mimics human pathophysiology. For this reason, the best models should closely resemble real-life conditions. Thus, the human model is the best. However, human models of respiratory infections have some disadvantages that limit their role. Therefore, other models, including animal, in vitro, and mathematical ones, have been developed. We will discuss advantages and limitations of available models and focus on models of viral infections as triggers of asthma exacerbations, viral infections being one of the most frequent causes of exacerbating disease. Future studies should focus on the interrelation of various models. PMID:26333698

  18. The New World arenavirus Tacaribe virus induces caspase-dependent apoptosis in infected cells.

    PubMed

    Wolff, Svenja; Groseth, Allison; Meyer, Bjoern; Jackson, David; Strecker, Thomas; Kaufmann, Andreas; Becker, Stephan

    2016-04-01

    The Arenaviridae is a diverse and growing family of viruses that already includes more than 25 distinct species. While some of these viruses have a significant impact on public health, others appear to be non-pathogenic. At present little is known about the host cell responses to infection with different arenaviruses, particularly those found in the New World; however, apoptosis is known to play an important role in controlling infection of many viruses. Here we show that infection with Tacaribe virus (TCRV), which is widely considered the prototype for non-pathogenic arenaviruses, leads to stronger induction of apoptosis than does infection with its human-pathogenic relative Junín virus. TCRV-induced apoptosis occurred in several cell types during late stages of infection and was shown to be caspase-dependent, involving the activation of caspases 3, 7, 8 and 9. Further, UV-inactivated TCRV did not induce apoptosis, indicating that the activation of this process is dependent on active viral replication/transcription. Interestingly, when apoptosis was inhibited, growth of TCRV was not enhanced, indicating that apoptosis does not have a direct negative effect on TCRV infection in vitro. Taken together, our data identify and characterize an important virus-host cell interaction of the prototypic, non-pathogenic arenavirus TCRV, which provides important insight into the growing field of arenavirus research aimed at better understanding the diversity in responses to different arenavirus infections and their functional consequences. PMID:26769540

  19. The effect of infectious bursal disease virus induced immunosuppression on avian influenza virus vaccine efficacy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the field, poultry are exposed to a variety of infectious agents, many of which are immunosuppressive. Co-infections between these agents are common, and these co-infections have effects on disease, immune response, and vaccine efficacy. The effect of co-infections in poultry between immunosupp...

  20. Utilizing the virus-induced blocking of apoptosis in an easy baculovirus titration method

    PubMed Central

    Niarchos, Athanasios; Lagoumintzis, George; Poulas, Konstantinos

    2015-01-01

    Baculovirus-mediated protein expression is a robust experimental technique for producing recombinant higher-eukaryotic proteins because it combines high yields with considerable post-translational modification capabilities. In this expression system, the determination of the titer of recombinant baculovirus stocks is important to achieve the correct multiplicity of infection for effective amplification of the virus and high expression of the target protein. To overcome the drawbacks of existing titration methods (e.g., plaque assay, real-time PCR), we present a simple and reliable assay that uses the ability of baculoviruses to block apoptosis in their host cells to accurately titrate virus samples. Briefly, after incubation with serial dilutions of baculovirus samples, Sf9 cells were UV irradiated and, after apoptosis induction, they were viewed via microscopy; the presence of cluster(s) of infected cells as islets indicated blocked apoptosis. Subsequently, baculovirus titers were calculated through the determination of the 50% endpoint dilution. The method is simple, inexpensive, and does not require unique laboratory equipment, consumables or expertise; moreover, it is versatile enough to be adapted for the titration of every virus species that can block apoptosis in any culturable host cells which undergo apoptosis under specific conditions. PMID:26490731

  1. Effect of adjuvants on immunization with dengue virus-induced cytotoxic factor.

    PubMed Central

    Mukerjee, R; Chaturvedi, U C

    1995-01-01

    Specific active immunization with dengue type 2 virus (DV)-induced cytokine, cytotoxic factor (CF), prevents CF-mediated pathology in mice. The present study was undertaken to determine the optimum dose of CF and the effect of different adjuvants on the immune response as assessed by the study of anti-CF antibody titre by ELISA and protection against increase in capillary permeability to challenging dose of 3 micrograms CF. The maximum protection of 94 +/- 4% against increase in capillary permeability was observed at week 4 after immunization with 5 micrograms dose of CF mixed with Freund's incomplete adjuvant (FIA), which gradually decreased to 21 +/- 10% on week 24. With a dose of 10 micrograms the protection obtained was 79 +/- 5%, but persisted for a longer time at a higher level. The response was poor with 1 microgram dose of CF. The mean anti-CF antibody titres gradually decreased after reaching the peak at week 4 after immunization. Mice immunized with different adjuvants emulsified with 5 micrograms CF were challenged at different intervals with 3 micrograms CF. Maximum protection observed with CF + tetanus toxoid (TT) and 84/246 was about 93 +/- 2% and 97 +/- 2%, while that with alhydrogel was 33 +/- 12% and with bacille Calmette-Guérin (BCG) was 67 +/- 4%. At week 24 after immunization, however, the best response was obtained with 10 micrograms of adjuvant 84/246. Intracerebral challenge with 10 or 100 LD50 dose of dengue type 2 virus showed significantly prolonged mean survival time and delayed onset of signs of sickness in immunized mice compared with normal mice. The maximum survival time was with adjuvant 84/246 even at week 24. The findings thus show that the optimum dose of CF is 5 micrograms and the adjuvant of choice is 84/246. PMID:8536363

  2. Marek's Disease Virus-Induced Immunosuppression: Array Analysis of Chicken Immune Response Gene Expression Profiling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marek’s disease (MD) is a lymphoproliferative disease of chickens induced by a highly cell-associated oncogenic alpha-herpesvirus, Marek’s disease virus (MDV). MDV replicates in chicken lymphocytes and establishes a latency infection within CD4+ T cells. Host-virus interaction, immune responses to...

  3. Well-tolerated Spirulina extract inhibits influenza virus replication and reduces virus-induced mortality

    PubMed Central

    Chen, Yi-Hsiang; Chang, Gi-Kung; Kuo, Shu-Ming; Huang, Sheng-Yu; Hu, I-Chen; Lo, Yu-Lun; Shih, Shin-Ru

    2016-01-01

    Influenza is one of the most common human respiratory diseases, and represents a serious public health concern. However, the high mutability of influenza viruses has hampered vaccine development, and resistant strains to existing anti-viral drugs have also emerged. Novel anti-influenza therapies are urgently needed, and in this study, we describe the anti-viral properties of a Spirulina (Arthrospira platensis) cold water extract. Anti-viral effects have previously been reported for extracts and specific substances derived from Spirulina, and here we show that this Spirulina cold water extract has low cellular toxicity, and is well-tolerated in animal models at one dose as high as 5,000 mg/kg, or 3,000 mg/kg/day for 14 successive days. Anti-flu efficacy studies revealed that the Spirulina extract inhibited viral plaque formation in a broad range of influenza viruses, including oseltamivir-resistant strains. Spirulina extract was found to act at an early stage of infection to reduce virus yields in cells and improve survival in influenza-infected mice, with inhibition of influenza hemagglutination identified as one of the mechanisms involved. Together, these results suggest that the cold water extract of Spirulina might serve as a safe and effective therapeutic agent to manage influenza outbreaks, and further clinical investigation may be warranted. PMID:27067133

  4. Immunity against heterosubtypic influenza virus induced by adenovirus and MVA expressing nucleoprotein and matrix protein-1.

    PubMed

    Lambe, Teresa; Carey, John B; Li, Yuanyuan; Spencer, Alexandra J; van Laarhoven, Arjan; Mullarkey, Caitlin E; Vrdoljak, Anto; Moore, Anne C; Gilbert, Sarah C

    2013-01-01

    Alternate prime/boost vaccination regimens employing recombinant replication-deficient adenovirus or MVA, expressing Influenza A virus nucleoprotein and matrix protein 1, induced antigen-specific T cell responses in intradermally (ID) vaccinated mice; with the strongest responses resulting from Ad/MVA immunization. In BALB/C mice the immunodominant response was shifted from the previously identified immunodominant epitope to a novel epitope when the antigen was derived from A/Panama/2007/1999 rather than A/PR/8. Alternate immunization routes did not affect the magnitude of antigen-specific systemic IFN-γ response, but higher CD8(+) T-cell IFN-γ immune responses were seen in the bronchoalveolar lavage following intransal (IN) boosting after intramuscular (IM) priming, whilst higher splenic antigen-specific CD8(+) T cell IFN-γ was seen following IM boosting. Partial protection against heterologous influenza virus challenge was achieved following either IM/IM or IM/IN but not ID/ID immunization. These data may be of relevance for the design of optimal immunization regimens for human influenza vaccines, especially for influenza-naïve infants. PMID:23485942

  5. Transcriptome Analysis of Capsicum Chlorosis Virus-Induced Hypersensitive Resistance Response in Bell Capsicum

    PubMed Central

    Widana Gamage, Shirani M. K.; McGrath, Desmond J.; Persley, Denis M.

    2016-01-01

    Background Capsicum chlorosis virus (CaCV) is an emerging pathogen of capsicum, tomato and peanut crops in Australia and South-East Asia. Commercial capsicum cultivars with CaCV resistance are not yet available, but CaCV resistance identified in Capsicum chinense is being introgressed into commercial Bell capsicum. However, our knowledge of the molecular mechanisms leading to the resistance response to CaCV infection is limited. Therefore, transcriptome and expression profiling data provide an important resource to better understand CaCV resistance mechanisms. Methodology/Principal Findings We assembled capsicum transcriptomes and analysed gene expression using Illumina HiSeq platform combined with a tag-based digital gene expression system. Total RNA extracted from CaCV/mock inoculated CaCV resistant (R) and susceptible (S) capsicum at the time point when R line showed a strong hypersensitive response to CaCV infection was used in transcriptome assembly. Gene expression profiles of R and S capsicum in CaCV- and buffer-inoculated conditions were compared. None of the genes were differentially expressed (DE) between R and S cultivars when mock-inoculated, while 2484 genes were DE when inoculated with CaCV. Functional classification revealed that the most highly up-regulated DE genes in R capsicum included pathogenesis-related genes, cell death-associated genes, genes associated with hormone-mediated signalling pathways and genes encoding enzymes involved in synthesis of defense-related secondary metabolites. We selected 15 genes to confirm DE expression levels by real-time quantitative PCR. Conclusion/Significance DE transcript profiling data provided comprehensive gene expression information to gain an understanding of the underlying CaCV resistance mechanisms. Further, we identified candidate CaCV resistance genes in the CaCV-resistant C. annuum x C. chinense breeding line. This knowledge will be useful in future for fine mapping of the CaCV resistance locus and potential genetic engineering of resistance into CaCV-susceptible crops. PMID:27398596

  6. Avian influenza virus-induced regulation of duck fibroblast gene expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly pathogenic avian influenza (HPAI) H5N1 viruses have been non-pathogenic in ducks causing no disease or mild respiratory infections. However, in 2002, new viruses emerged causing systemic disease and death. To better understand the differences in pathogenicity of HPAI viruses in ducks, we in...

  7. Multiple transport systems mediate virus-induced acquired resistance to oxidative stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, we report the phenomenon of acquired cross-tolerance to oxidative (UV-C and H2O2) stress in Nicotiana benthamiana plants infected with Potato virus X (PVX) and investigate the functional expression of transport systems in mediating this phenomenon. By combining multiple approaches, we...

  8. Endomembrane Ca2+ -ATPases play significant role in virus-induced adaptation to oxidative stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In our recently published paper (Plant Cell Environ 34: 406-417) we have reported a phenomenon of Potato Virus X (PVX) - induced cross tolerance to oxidative stress in Nicotiana benthamiana plants and showed a critical role of plasma membrane Ca2+/H+ exchangers in this process. The current study fol...

  9. Protective effects of macrophage-derived interferon against encephalomyocarditis virus-induced diabetes mellitus in mice.

    PubMed

    Hirasawa, K; Ogiso, Y; Takeda, M; Lee, M J; Itagaki, S; Doi, K

    1995-12-01

    The involvement of macrophages in protection against diabetes mellitus in mice of BALB/c (susceptible) and C57BL (resistant) strains infected with the B (non-diabetogenic) or D (highly diabetogenic) variant of encephalomyocarditis (EMC) virus was examined. Pretreatment with the B variant of EMC virus (EMC-B), avirulent interferon (IFN) inducer, or Corynebacterium parvum inhibited diabetes in BALB/c mice infected with the D variant of EMC virus (EMC-D). Treatment of C57BL mice with carrageenan to compromise macrophage function rendered C57BL mice susceptible to EMC-D-induced diabetes. In macrophage culture for BALB/c mice, EMC-B induced IFN at an earlier stage than did EMC-D. The C57BL mouse-derived macrophages produced more IFN than did BALB/c mouse-derived macrophages after stimulation with EMC-D. Moreover, C. parvum increased IFN production in macrophage cultures from BALB/c mice, whereas carrageenan inhibited that in macrophage cultures from C57BL mice. These results suggest that IFN derived from macrophages may have an important role in protecting mice against EMC virus infection. PMID:8746525

  10. A generic screening platform for inhibitors of virus induced cell fusion using cellular electrical impedance

    PubMed Central

    Watterson, Daniel; Robinson, Jodie; Chappell, Keith J.; Butler, Mark S.; Edwards, David J.; Fry, Scott R.; Bermingham, Imogen M.; Cooper, Matthew A.; Young, Paul R.

    2016-01-01

    Fusion of the viral envelope with host cell membranes is an essential step in the life cycle of all enveloped viruses. Despite such a clear target for antiviral drug development, few anti-fusion drugs have progressed to market. One significant hurdle is the absence of a generic, high-throughput, reproducible fusion assay. Here we report that real time, label-free measurement of cellular electrical impedance can quantify cell-cell fusion mediated by either individually expressed recombinant viral fusion proteins, or native virus infection. We validated this approach for all three classes of viral fusion and demonstrated utility in quantifying fusion inhibition using antibodies and small molecule inhibitors specific for dengue virus and respiratory syncytial virus. PMID:26976324

  11. Hepatitis B and C virus-induced hepatitis: Apoptosis, autophagy, and unfolded protein response

    PubMed Central

    Yeganeh, Behzad; Rezaei Moghadam, Adel; Alizadeh, Javad; Wiechec, Emilia; Alavian, Seyed Moayed; Hashemi, Mohammad; Geramizadeh, Bita; Samali, Afshin; Bagheri Lankarani, Kamran; Post, Martin; Peymani, Payam; Coombs, Kevin M; Ghavami, Saeid

    2015-01-01

    AIM: To investigate the co-incidence of apoptosis, autophagy, and unfolded protein response (UPR) in hepatitis B (HBV) and C (HCV) infected hepatocytes. METHODS: We performed immunofluorescence confocal microscopy on 10 liver biopsies from HBV and HCV patients and tissue microarrays of HBV positive liver samples. We used specific antibodies for LC3β, cleaved caspase-3, BIP (GRP78), and XBP1 to detect autophagy, apoptosis and UPR, respectively. Anti-HCV NS3 and anti-HBs antibodies were also used to confirm infection. We performed triple blind counting of events to determine the co-incidence of autophagy (LC3β punctuate), apoptosis (cleaved caspase-3), and unfolded protein response (GRP78) with HBV and HCV infection in hepatocytes. All statistical analyses were performed using SPSS software for Windows (Version 16 SPSS Inc, Chicago, IL, United States). P-values < 0.05 were considered statistically significant. Statistical analyses were performed with Mann-Whitney test to compare incidence rates for autophagy, apoptosis, and UPR in HBV- and HCV-infected cells and adjacent non-infected cells. RESULTS: Our results showed that infection of hepatocytes with either HBV and HCV induces significant increase (P < 0.001) in apoptosis (cleavage of caspase-3), autophagy (LC3β punctate), and UPR (increase in GRP78 expression) in the HCV- and HBV-infected cells, as compared to non-infected cells of the same biopsy sections. Our tissue microarray immunohistochemical expression analysis of LC3β in HBVNeg and HBVPos revealed that majority of HBV-infected hepatocytes display strong positive staining for LC3β. Interestingly, although XBP splicing in HBV-infected cells was significantly higher (P < 0.05), our analyses show a slight increase of XBP splicing was in HCV-infected cells (P > 0.05). Furthermore, our evaluation of patients with HBV and HCV infection based on stage and grade of the liver diseases revealed no correlation between these pathological findings and induction of apoptosis, autophagy, and UPR. CONCLUSION: The results of this study indicate that HCV and HBV infection activates apoptosis, autophagy and UPR, but slightly differently by each virus. Further studies are warranted to elucidate the interconnections between these pathways in relation to pathology of HCV and HBV in the liver tissue. PMID:26715805

  12. Virus-induced type I IFN stimulates generation of immunoproteasomes at the site of infection

    PubMed Central

    Shin, Eui-Cheol; Seifert, Ulrike; Kato, Takanobu; Rice, Charles M.; Feinstone, Stephen M.; Kloetzel, Peter-M.; Rehermann, Barbara

    2006-01-01

    IFN-γ is known as the initial and primary inducer of immunoproteasomes during viral infections. We now report that type I IFN induced the transcription and translation of immunoproteasome subunits, their incorporation into the proteasome complex, and the generation of an immunoproteasome-dependent CD8 T cell epitope in vitro and provide in vivo evidence that this mechanism occurs prior to IFN-γ responses at the site of viral infection. Type I IFN–mediated generation of immunoproteasomes was initiated by either poly(I:C) or HCV RNA in human hepatoma cells and was inhibited by neutralization of type I IFN. In serial liver biopsies of chimpanzees with acute HCV infection, increases in immunoproteasome subunit mRNA preceded intrahepatic IFN-γ responses by several weeks, instead coinciding with intrahepatic type I IFN responses. Thus, viral RNA–induced innate immune responses regulate the antigen-processing machinery, which occurs prior to the detection of IFN-γ at the site of infection. This mechanism may contribute to the high effectiveness (95%) of type I IFN–based therapies if administered early during HCV infection. PMID:17039255

  13. Pathogenesis and prevention of hepatitis C virus-induced hepatocellular carcinoma.

    PubMed

    Hoshida, Yujin; Fuchs, Bryan C; Bardeesy, Nabeel; Baumert, Thomas F; Chung, Raymond T

    2014-11-01

    Hepatitis C virus (HCV) is one of the major aetiologic agents that causes hepatocellular carcinoma (HCC) by generating an inflammatory, fibrogenic, and carcinogenic tissue microenvironment in the liver. HCV-induced HCC is a rational target for cancer preventive intervention because of the clear-cut high-risk condition, cirrhosis, associated with high cancer incidence (1% to 7% per year). Studies have elucidated direct and indirect carcinogenic effects of HCV, which have in turn led to the identification of candidate HCC chemoprevention targets. Selective molecular targeted agents may enable personalized strategies for HCC chemoprevention. In addition, multiple experimental and epidemiological studies suggest the potential value of generic drugs or dietary supplements targeting inflammation, oxidant stress, or metabolic derangements as possible HCC chemopreventive agents. While the successful use of highly effective direct-acting antiviral agents will make important inroads into reducing long-term HCC risk, there will remain an important role for HCC chemoprevention even after viral cure, given the persistence of HCC risk in persons with advanced HCV fibrosis, as shown in recent studies. The successful development of cancer preventive therapies will be more challenging compared to cancer therapeutics because of the requirement for larger and longer clinical trials and the need for a safer toxicity profile given its use as a preventive agent. Molecular biomarkers to selectively identify high-risk population could help mitigate these challenges. Genome-wide, unbiased molecular characterization, high-throughput drug/gene screening, experimental model-based functional analysis, and systems-level in silico modelling are expected to complement each other to facilitate discovery of new HCC chemoprevention targets and therapies. PMID:25443348

  14. Pathogenesis and prevention of hepatitis C virus-induced hepatocellular carcinoma

    PubMed Central

    Hoshida, Yujin; Fuchs, Bryan C.; Bardeesy, Nabeel; Baumert, Thomas F.; Chung, Raymond T.

    2015-01-01

    Summary Hepatitis C virus (HCV) is one of the major etiologic agents that causes hepatocellular carcinoma (HCC) by generating an inflammatory, fibrogenic, and carcinogenic tissue microenvironment in the liver. HCV-induced HCC is a rational target for cancer preventive intervention because of the clear-cut high-risk condition, cirrhosis, associated with high cancer incidence (1% to 7% per year). Studies have elucidated direct and indirect carcinogenic effects of HCV, which have in turn led to identification of candidate HCC chemoprevention targets. Selective molecular targeted agents may enable personalized strategies for HCC chemoprevention. In addition, multiple experimental and epidemiological studies suggest the potential value of generic drugs or dietary supplements targeting inflammation, oxidant stress, or metabolic derangements as possible HCC chemopreventive agents. While the successful use of highly effective direct-acting antiviral agents will make important inroads into reducing long term HCC risk, there will remain an important role for HCC chemoprevention even after viral cure, given the persistence of HCC risk in persons with advanced HCV fibrosis as shown in recent studies. The successful development of cancer preventive therapies will be more challenging compared to cancer therapeutics because of the requirement for larger and longer clinical trials and the need for a safer toxicity profile given its use as a preventive agent. Molecular biomarkers to selectively identify high-risk population could help mitigate these challenges. Genome-wide, unbiased molecular characterization, high-throughput drug/gene screening, experimental model-based functional analysis, and systems-level in silico modeling are expected to complement each other to facilitate discovery of new HCC chemoprevention targets and therapies. PMID:25443348

  15. NITROTYROSINE INHIBITS RESPIRATORY SYNCTIAL VIRUS-INDUCED RANTES PRODUCTION IN HUMAN BRONCHIAL EPITHELIAL CELLS

    EPA Science Inventory

    3-Nitrotyrosine (NO2Tyr) produced during inflammation can substitute the C-terminus tyrosine of a-tubulin post-translationally altering microtubular functions. Since propagation of respiratory syncytial virus (RSV) infection may require an intact microtubular activity, we tested ...

  16. γδ T Cells Play a Protective Role in Chikungunya Virus-Induced Disease

    PubMed Central

    Ferris, Martin T.; Whitmore, Alan C.; Montgomery, Stephanie A.; Thurlow, Lance R.; McGee, Charles E.; Rodriguez, Carlos A.; Lim, Jean K.; Heise, Mark T.

    2015-01-01

    ABSTRACT Chikungunya virus (CHIKV) is an alphavirus responsible for causing epidemic outbreaks of polyarthralgia in humans. Because CHIKV is initially introduced via the skin, where γδ T cells are prevalent, we evaluated the response of these cells to CHIKV infection. CHIKV infection led to a significant increase in γδ T cells in the infected foot and draining lymph node that was associated with the production of proinflammatory cytokines and chemokines in C57BL/6J mice. γδ T cell−/− mice demonstrated exacerbated CHIKV disease characterized by less weight gain and greater foot swelling than occurred in wild-type mice, as well as a transient increase in monocytes and altered cytokine/chemokine expression in the foot. Histologically, γδ T cell−/− mice had increased inflammation-mediated oxidative damage in the ipsilateral foot and ankle joint compared to wild-type mice which was independent of differences in CHIKV replication. These results suggest that γδ T cells play a protective role in limiting the CHIKV-induced inflammatory response and subsequent tissue and joint damage. IMPORTANCE Recent epidemics, including the 2004 to 2007 outbreak and the spread of CHIKV to naive populations in the Caribbean and Central and South America with resultant cases imported into the United States, have highlighted the capacity of CHIKV to cause explosive epidemics where the virus can spread to millions of people and rapidly move into new areas. These studies identified γδ T cells as important to both recruitment of key inflammatory cell populations and dampening the tissue injury due to oxidative stress. Given the importance of these cells in the early response to CHIKV, this information may inform the development of CHIKV vaccines and therapeutics. PMID:26491151

  17. Suppressor T cell clones from patients with acute Epstein-Barr virus-induced infectious mononucleosis.

    PubMed Central

    Wang, F; Blaese, R M; Zoon, K C; Tosato, G

    1987-01-01

    Suppression and/or cytotoxicity are believed to play an important role in the defense against Epstein-Barr virus (EBV) infection. To analyze the role of suppressor T cells in relation to EBV, we sought to clone and study these T cells. Analysis of 152 T cell clones derived from the peripheral blood of two patients with acute EBV-induced infectious mononucleosis (IM) yielded 11 highly suppressive clones that had no cytotoxic activity for the natural killer sensitive K562 cell line, an autologous EBV-infected cell line, or an allogeneic EBV-infected B cell line. Four of six suppressor T cell clones also profoundly inhibited EBV-induced immunoglobulin production, and five of five clones delayed the outgrowth of immortalized cells. These results indicate that during acute IM, suppressor T cells capable of inhibiting B cell activation in the absence of cytotoxicity can be identified, and may play a key role in the control of EBV infection. Images PMID:3025263

  18. Bovine leukemia virus-induced clinical signs and morphological changes of encephalitozoonosis in rabbits.

    PubMed

    Levkut, M; Lesník, F; Bálent, P; Zajac, V; Korim, P; Sláviková, K

    1997-01-01

    Fourteen three-month-old rabbits spontaneously-infected with the microsporidium Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923 were inoculated intravenously with lymphocytes (Ly) from seropositive bovine leukemia virus infected cattle (Ly/BLV) or with fetal lamb kidney cells infected with bovine fetal leukemia (FLK/BLV). Thirteen rabbits were seropositive to BLV at least for a period of three months. Six rabbits died of pulmonary lesions. Chronic inflammatory lesions of encephalitozoonosis were found in six rabbits killed between 454 and 548 days of the observation period. Five animals bore subcutaneous granulomas. Immunohistochemically, E. cuniculi was demonstrated in the inflammatory lesions of rabbits studied. Control animals also spontaneously infected with E. cuniculi did not show clinical signs of encephalitozoonosis. Morphological changes were found incidentally in the form of small glial foci and focal interstitial nephritis in these animals. The combined action of BLV-E. cuniculi on the bodies of rabbits is proposed as a suitable model for the study of encephalitozoonosis in man with human immunodeficiency virus (HIV) infection. PMID:9437837

  19. Heliox reduces respiratory system resistance in respiratory syncytial virus induced respiratory failure

    PubMed Central

    Kneyber, Martin CJ; van Heerde, Marc; Twisk, Jos WR; Plötz, Frans B; Markhors, Dick G

    2009-01-01

    Introduction Respiratory syncytial virus (RSV) lower respiratory tract disease is characterised by narrowing of the airways resulting in increased airway resistance, air-trapping and respiratory acidosis. These problems might be overcome using helium-oxygen gas mixture. However, the effect of mechanical ventilation with heliox in these patients is unclear. The objective of this prospective cross-over study was to determine the effects of mechanical ventilation with heliox 60/40 versus conventional gas on respiratory system resistance, air-trapping and CO2 removal. Methods Mechanically ventilated, sedated and paralyzed infants with proven RSV were enrolled within 24 hours after paediatric intensive care unit (PICU)admission. At T = 0, respiratory system mechanics including respiratory system compliance and resistance, and peak expiratory flow rate were measured with the AVEA ventilator. The measurements were repeated at each interval (after 30 minutes of ventilation with heliox, after 30 minutes of ventilation with nitrox and again after 30 minutes of ventilation with heliox). Indices of gas exchange (ventilation and oxygenation index) were calculated at each interval. Air-trapping (defined by relative change in end-expiratory lung volume) was determined by electrical impedance tomography (EIT) at each interval. Results Thirteen infants were enrolled. In nine, EIT measurements were performed. Mechanical ventilation with heliox significantly decreased respiratory system resistance. This was not accompanied by an improved CO2 elimination, decreased peak expiratory flow rate or decreased end-expiratory lung volume. Importantly, oxygenation remained unaltered throughout the experimental protocol. Conclusions Respiratory system resistance is significantly decreased by mechanical ventilation with heliox (ISCRTN98152468). PMID:19450268

  20. RNA-mediated RNA degradation in transgene- and virus-induced gene silencing.

    PubMed

    Metzlaff, Michael

    2002-10-01

    In the 'RNA world' hypothesis it is postulated that RNA was the first genetic molecule. Recent discoveries in gene silencing research on plants, fungi and animals show that RNA indeed plays a key role not only in controlling invading nucleic acids, like viruses and transposable elements, but also in regulating the expression of transgenes and endogenous genes. Double-stranded RNAs were identified to be the triggering structures for the induction of a specific and highly efficient RNA silencing system, in which enzyme complexes, like Dicer and RISC, facilitate as 'molecular machines' the processing of dsRNA into characteristic small RNA species. RNA silencing can be transmitted rapidly from silenced to non-silenced cells by short and long distance signaling. There is evidence that at least one component of the signal is a specific, degradation-resistant RNA. PMID:12452426

  1. Neutral Sphingomyelinase in Physiological and Measles Virus Induced T Cell Suppression

    PubMed Central

    Collenburg, Lena; Grassmé, Heike; Schneider-Schaulies, Sibylle

    2014-01-01

    T cell paralysis is a main feature of measles virus (MV) induced immunosuppression. MV contact mediated activation of sphingomyelinases was found to contribute to MV interference with T cell actin reorganization. The role of these enzymes in MV-induced inhibition of T cell activation remained equally undefined as their general role in regulating immune synapse (IS) activity which relies on spatiotemporal membrane patterning. Our study for the first time reveals that transient activation of the neutral sphingomyelinase 2 (NSM2) occurs in physiological co-stimulation of primary T cells where ceramide accumulation is confined to the lamellum (where also NSM2 can be detected) and excluded from IS areas of high actin turnover. Genetic ablation of the enzyme is associated with T cell hyper-responsiveness as revealed by actin dynamics, tyrosine phosphorylation, Ca2+-mobilization and expansion indicating that NSM2 acts to suppress overshooting T cell responses. In line with its suppressive activity, exaggerated, prolonged NSM2 activation as occurring in co-stimulated T cells following MV exposure was associated with aberrant compartmentalization of ceramides, loss of spreading responses, interference with accumulation of tyrosine phosphorylated protein species and expansion. Altogether, this study for the first time reveals a role of NSM2 in physiological T cell stimulation which is dampening and can be abused by a virus, which promotes enhanced and prolonged NSM2 activation to cause pathological T cell suppression. PMID:25521388

  2. Venezuelan Equine Encephalitis Virus Induces Apoptosis through the Unfolded Protein Response Activation of EGR1

    PubMed Central

    Baer, Alan; Lundberg, Lindsay; Swales, Danielle; Waybright, Nicole; Pinkham, Chelsea; Dinman, Jonathan D.

    2016-01-01

    ABSTRACT Venezuelan equine encephalitis virus (VEEV) is a previously weaponized arthropod-borne virus responsible for causing acute and fatal encephalitis in animal and human hosts. The increased circulation and spread in the Americas of VEEV and other encephalitic arboviruses, such as eastern equine encephalitis virus and West Nile virus, underscore the need for research aimed at characterizing the pathogenesis of viral encephalomyelitis for the development of novel medical countermeasures. The host-pathogen dynamics of VEEV Trinidad donkey-infected human astrocytoma U87MG cells were determined by carrying out RNA sequencing (RNA-Seq) of poly(A) and mRNAs. To identify the critical alterations that take place in the host transcriptome following VEEV infection, samples were collected at 4, 8, and 16 h postinfection and RNA-Seq data were acquired using an Ion Torrent PGM platform. Differential expression of interferon response, stress response factors, and components of the unfolded protein response (UPR) was observed. The protein kinase RNA-like endoplasmic reticulum kinase (PERK) arm of the UPR was activated, as the expression of both activating transcription factor 4 (ATF4) and CHOP (DDIT3), critical regulators of the pathway, was altered after infection. Expression of the transcription factor early growth response 1 (EGR1) was induced in a PERK-dependent manner. EGR1−/− mouse embryonic fibroblasts (MEFs) demonstrated lower susceptibility to VEEV-induced cell death than isogenic wild-type MEFs, indicating that EGR1 modulates proapoptotic pathways following VEEV infection. The influence of EGR1 is of great importance, as neuronal damage can lead to long-term sequelae in individuals who have survived VEEV infection. IMPORTANCE Alphaviruses represent a group of clinically relevant viruses transmitted by mosquitoes to humans. In severe cases, viral spread targets neuronal tissue, resulting in significant and life-threatening inflammation dependent on a combination of virus-host interactions. Currently there are no therapeutics for infections cause by encephalitic alphaviruses due to an incomplete understanding of their molecular pathogenesis. Venezuelan equine encephalitis virus (VEEV) is an alphavirus that is prevalent in the Americas and that is capable of infecting horses and humans. Here we utilized next-generation RNA sequencing to identify differential alterations in VEEV-infected astrocytes. Our results indicated that the abundance of transcripts associated with the interferon and the unfolded protein response pathways was altered following infection and demonstrated that early growth response 1 (EGR1) contributed to VEEV-induced cell death. PMID:26792742

  3. Enhancement of basophil chemotaxis in vitro by virus-induced interferon.

    PubMed Central

    Lett-Brown, M A; Aelvoet, M; Hooks, J J; Georgiades, J A; Thueson, D O; Grant, J A

    1981-01-01

    It is well established that viral infections may precipitate or worsen attacks of bronchial asthma. Furthermore, in symptomatic atopic subjects, the local accumulation of basophils and the production of a basophil chemotactic factor have been reported. We have investigated the effect of cell-free supernates from viral stimulated cultures of human mononuclear cells on the in vitro migration of human basophils. Our results show the presence of a factor in these culture supernates that enhances the migration of basophils toward two separate chemoattractants, a peptide from C5 and a lymphokine. The enhancing activity, while affecting basophil migration, did not change the response of monocytes. The enhancing activity resembled viral-induced interferon when (a) pH 2 stability, (b) heat resistance, (c) trypsin sensitivity, and (d) species-specificity were compared. Finally, the enhancing activity for basophil chemotaxis and the interferon titer were highly correlated in preparations with a 10(4)-fold difference in interferon specific activity. Our studies show that viral-induced interferon can augment the in vitro chemotactic response of basophils. Because mediators present in basophils may be involved in the pathogenesis of immediate hypersensitivity, the modulation of basophil movement by interferon suggests a possible mechanism for the association between viral infections and atopic disorders. PMID:6161946

  4. Isolation and characterization of a tobacco mosaic virus-inducible myb oncogene homolog from tobacco

    PubMed Central

    Yang, Yinong; Klessig, Daniel F.

    1996-01-01

    Salicylic acid (SA) plays an important role in signaling the activation of plant defense responses against pathogen attack including induction of pathogenesis-related (PR) proteins. To gain further insight into the SA-mediated signal transduction pathway, we have isolated and characterized a tobacco mosaic virus (TMV)-inducible myb oncogene homolog (myb1) from tobacco. The myb1 gene was induced upon TMV infection during both the hypersensitive response and development of systemic acquired resistance in the resistant tobacco cultivar following the rise of endogenous SA, but was not activated in the susceptible cultivar that fails to accumulate SA. The myb1 gene was also induced by incompatible bacterial pathogen Pseudomonas syringae pv. syringae during the hypersensitive response. Exogenous SA treatment rapidly (within 15 min) activated the expression of myb1 in both resistant and susceptible tobacco cultivars with the subsequent induction of PR genes occurring several hours later. Biologically active analogs of SA and 2,6-dichloroisonicotinic acid (a synthetic functional analog of SA), which induce PR genes and enhanced resistance, also activated the myb1 gene. In contrast, biologically inactive analogs were poor inducers of myb1 gene expression. Furthermore, the recombinant Myb1 protein was shown to specifically bind to a Myb-binding consensus sequence found in the promoter of the PR-1a gene. Taken together, these results suggest that the tobacco myb1 gene encodes a signaling component downstream of SA that may participate in transcriptional activation of PR genes and plant disease resistance. PMID:8962166

  5. Dengue Virus Induces Novel Changes in Gene Expression of Human Umbilical Vein Endothelial Cells

    PubMed Central

    Warke, Rajas V.; Xhaja, Kris; Martin, Katherine J.; Fournier, Marcia F.; Shaw, Sunil K.; Brizuela, Nathaly; de Bosch, Norma; Lapointe, David; Ennis, Francis A.; Rothman, Alan L.; Bosch, Irene

    2003-01-01

    Endothelial cells are permissive to dengue virus (DV) infection in vitro, although their importance as targets of DV infection in vivo remains a subject of debate. To analyze the virus-host interaction, we studied the effect of DV infection on gene expression in human umbilical vein endothelial cells (HUVECs) by using differential display reverse transcription-PCR (DD-RTPCR), quantitative RT-PCR, and Affymetrix oligonucleotide microarrays. DD identified eight differentially expressed cDNAs, including inhibitor of apoptosis-1, 2′-5′ oligoadenylate synthetase (OAS), a 2′-5′ OAS-like (OASL) gene, galectin-9, myxovirus protein A (MxA), regulator of G-protein signaling, endothelial and smooth muscle cell-derived neuropilin-like protein, and phospholipid scramblase 1. Microarray analysis of 22,000 human genes confirmed these findings and identified an additional 269 genes that were induced and 126 that were repressed more than fourfold after DV infection. Broad functional responses that were activated included the stress, defense, immune, cell adhesion, wounding, inflammatory, and antiviral pathways. These changes in gene expression were seen after infection of HUVECs with either laboratory-adapted virus or with virus isolated directly from plasma of DV-infected patients. Tumor necrosis factor alpha, OASL, and MxA and h-IAP1 genes were induced within the first 8 to 12 h after infection, suggesting a direct effect of DV infection. These global analyses of DV effects on cellular gene expression identify potentially novel mechanisms involved in dengue disease manifestations such as hemostatic disturbance. PMID:14557666

  6. Dysregulation of apoptotic death in the pathogenesis of virus-induced cytogenetic instability of blood lymphocytes.

    PubMed

    Ryazantseva, N V; Novitskii, V V; Zhukova, O B; Radzivil, T T; Mikheev, S L; Chechina, O E; Zima, A P; Shilov, B V

    2006-05-01

    The cytogenetic status and activity of regulatory systems for stability of the cell genome were evaluated in patients with chronic viral persistence. Hepatitis B and C viruses damage the chromosome apparatus of peripheral blood lymphocytes. Cytogenetic instability of immunocompetent cells during chronic viral infection was associated with inhibition of DNA excision repair system and dysregulation of apoptosis in target cells. PMID:17181065

  7. Human immunodeficiency virus-induced pathology favored by cellular transmission and activation

    SciTech Connect

    Lewis, D.E.; Yoffe, B.; Bosworth, C.G.; Hollinger, F.B.; Rich, R.R.

    1988-03-01

    Epidemiological data suggest that transmission of human immunodeficiency virus (HIV) occurs primarily by transference of virally infected cells. However, the efficiency of lytic productive infection induced by HIV after transmission of cell-associated virus vs. free virus is difficult to assess. The present studies compare the extent of depletion of CD4+ (helper/inducer) T cells after mixing uninfected cells with either free HIV or irradiated HIV-infected allogeneic or autologous cells in vitro. Rapid CD4+ cellular depletion occurred only in cultures containing allogeneic infected cells or after addition of a nonspecific T cell activation signal to cultures with autologous infected cells. These in vitro observations strongly support the epidemiological implication that interactions between infected and uninfected cells are the most efficient means of transmission and HIV-induced cytopathology in vivo. They also provide direct support for the concept that immunological stimulation by foreign cells infected with HIV dramatically increases the likelihood of transmission. These in vitro observations suggest a model for the acquisition of HIV in vivo and the role of cellular activation in dissemination of the virus to uninfected cells in an infected individual.

  8. Mumps Virus Induces Protein-Kinase-R-Dependent Stress Granules, Partly Suppressing Type III Interferon Production

    PubMed Central

    Hashimoto, Shin; Yamamoto, Soh; Ogasawara, Noriko; Sato, Toyotaka; Yamamoto, Keisuke; Katoh, Hiroshi; Kubota, Toru; Shiraishi, Tsukasa; Kojima, Takashi; Himi, Tetsuo; Tsutsumi, Hiroyuki; Yokota, Shin-ichi

    2016-01-01

    Stress granules (SGs) are cytoplasmic granular aggregations that are induced by cellular stress, including viral infection. SGs have opposing antiviral and proviral roles, which depend on virus species. The exact function of SGs during viral infection is not fully understood. Here, we showed that mumps virus (MuV) induced SGs depending on activation of protein kinase R (PKR). MuV infection strongly induced interferon (IFN)-λ1, 2 and 3, and IFN-β through activation of IFN regulatory factor 3 (IRF3) via retinoic acid inducible gene-I (RIG-I) and the mitochondrial antiviral signaling (MAVS) pathway. MuV-induced IFNs were strongly upregulated in PKR-knockdown cells. MuV-induced SG formation was suppressed by knockdown of PKR and SG marker proteins, Ras-GTPase-activating protein SH3-domain-binding protein 1 and T-cell-restricted intracellular antigen-1, and significantly increased the levels of MuV-induced IFN-λ1. However, viral titer was not altered by suppression of SG formation. PKR was required for induction of SGs by MuV infection and regulated type III IFN (IFN-λ1) mRNA stability. MuV-induced SGs partly suppressed type III IFN production by MuV; however, the limited suppression was not sufficient to inhibit MuV replication in cell culture. Our results provide insight into the relationship between SGs and IFN production induced by MuV infection. PMID:27560627

  9. Mumps virus-induced innate immune responses in mouse Sertoli and Leydig cells

    PubMed Central

    Wu, Han; Shi, Lili; Wang, Qing; Cheng, Lijing; Zhao, Xiang; Chen, Qiaoyuan; Jiang, Qian; Feng, Min; Li, Qihan; Han, Daishu

    2016-01-01

    Mumps virus (MuV) infection frequently causes orchitis and impairs male fertility. However, the mechanisms underlying the innate immune responses to MuV infection in the testis have yet to be investigated. This study showed that MuV induced innate immune responses in mouse Sertoli and Leydig cells through TLR2 and retinoic acid-inducible gene I (RIG-I) signaling, which result in the production of proinflammatory cytokines and chemokines, including TNF-α, IL-6, MCP-1, CXCL10, and type 1 interferons (IFN-α and IFN-β). By contrast, MuV did not induce the cytokine production in male germ cells. In response to MuV infection, Sertoli cells produced higher levels of proinflammatory cytokines and chemokines but lower levels of type 1 IFNs than Leydig cells did. The MuV-induced cytokine production by Sertoli and Leydig cells was significantly reduced by the knockout of TLR2 or the knockdown of RIG-I signaling. The local injection of MuV into the testis triggered the testicular innate immune responses in vivo. Moreover, MuV infection suppressed testosterone synthesis by Leydig cells. This is the first study examining the innate immune responses to MuV infection in testicular cells. The results provide novel insights into the mechanisms underlying the MuV-induced innate immune responses in the testis. PMID:26776505

  10. Dengue virus-induced thymus-derived suppressor cells in the spleen of mice.

    PubMed Central

    Tandon, P; Chaturvedi, U C; Mathur, A

    1979-01-01

    Adoptive transfer of spleen cells obtained from mice given three weekly i.p. doses of dengue type 2 virus (DV) suppressed DV antigen-specific antibody secretion as detected by the Jerne plaque technique. This suppression was produced by non-glass-adherent cells but not by glass-adherent cells. Immune spleen cells depleted of macrophages by carbonyl iron treatment had higher suppressor activity. Immune spleen cell homogenate could transfer the activity equally well. The immune spleen cells were separated into T and B lymphocytes by a nylon wool column. B lymphocytes had no suppressor activity; almost all the suppressor activity was present in T lymphocytes. Thus, macrophages and B lymphocytes had no suppressor activity; it was mediated by T lymphocytes through soluble factors. PMID:160396

  11. Hepatitis E Virus-Induced Cryoglobulinemic Glomerulonephritis in a Nonimmunocompromised Person.

    PubMed

    Guinault, Damien; Ribes, David; Delas, Audrey; Milongo, David; Abravanel, Florence; Puissant-Lubrano, Bénédicte; Izopet, Jacques; Kamar, Nassim

    2016-04-01

    Hepatitis E virus (HEV)-related kidney disease and symptomatic cryoglobulinemia have been observed in solid-organ transplant recipients. However, HEV RNA in the cryoprecipitate has not yet been assessed. We report what to our knowledge is the first documented case of autochthonous HEV-induced cryoglobulinemic crescentic and membranoproliferative glomerulonephritis in an immunocompetent man with no notable medical history. He presented with edema, hypertension, increased serum creatinine level, and nephrotic syndrome. Type II cryoglobulinemia with monoclonal immunoglobulin G (IgG) κ light chain was detected. Anti-HEV IgG and IgM, as well as HEV RNA, were detected in serum and cryoprecipitate. Histologic analysis of a kidney biopsy specimen revealed features of crescentic and membranoproliferative glomerulonephritis. After HEV clearance, kidney and liver parameters improved and HEV RNA and cryoglobulinemia were undetectable. Hence, we conclude that HEV can cause severe kidney disease and should be considered in cases of unexplained glomerular disease. PMID:26682764

  12. Well-tolerated Spirulina extract inhibits influenza virus replication and reduces virus-induced mortality.

    PubMed

    Chen, Yi-Hsiang; Chang, Gi-Kung; Kuo, Shu-Ming; Huang, Sheng-Yu; Hu, I-Chen; Lo, Yu-Lun; Shih, Shin-Ru

    2016-01-01

    Influenza is one of the most common human respiratory diseases, and represents a serious public health concern. However, the high mutability of influenza viruses has hampered vaccine development, and resistant strains to existing anti-viral drugs have also emerged. Novel anti-influenza therapies are urgently needed, and in this study, we describe the anti-viral properties of a Spirulina (Arthrospira platensis) cold water extract. Anti-viral effects have previously been reported for extracts and specific substances derived from Spirulina, and here we show that this Spirulina cold water extract has low cellular toxicity, and is well-tolerated in animal models at one dose as high as 5,000 mg/kg, or 3,000 mg/kg/day for 14 successive days. Anti-flu efficacy studies revealed that the Spirulina extract inhibited viral plaque formation in a broad range of influenza viruses, including oseltamivir-resistant strains. Spirulina extract was found to act at an early stage of infection to reduce virus yields in cells and improve survival in influenza-infected mice, with inhibition of influenza hemagglutination identified as one of the mechanisms involved. Together, these results suggest that the cold water extract of Spirulina might serve as a safe and effective therapeutic agent to manage influenza outbreaks, and further clinical investigation may be warranted. PMID:27067133

  13. Murine immunodeficiency virus-induced peripheral neuropathy and the associated cytokine responses.

    PubMed

    Cao, Ling; Butler, M Brady; Tan, Leonard; Draleau, Kyle S; Koh, Woon Yuen

    2012-10-01

    Distal symmetrical polyneuropathy is the most common form of HIV infection-associated peripheral neuropathy and is often associated with pain. C57BL/6 (B6) mice infected with LP-BM5, a murine retroviral isolate, develop a severe immunodeficiency syndrome similar to that in humans infected with HIV-1, hence the term murine AIDS. We investigated the induction of peripheral neuropathy after LP-BM5 infection in B6 mice. Infected B6 mice, like HIV-infected humans, exhibited behavioral (increased sensitivity to mechanical and heat stimuli) and pathological (transient loss of intraepidermal nerve fibers) signs of peripheral neuropathy. The levels of viral gag RNA were significantly increased in all tissues tested, including spleen, paw skin, lumbar dorsal root ganglia, and lumbar spinal cord, postinfection (p.i.). Correlated with the development of peripheral neuropathy, the tissue levels of several cytokines, including IFN-γ, IL-1β, IL-6, and IL-12, were significantly elevated p.i. These increases had cytokine-specific and tissue-specific profiles and kinetics. Further, treatment with the antiretroviral agent zidovudine either significantly reduced or completely reversed the aforementioned behavioral, pathologic, and cytokine changes p.i. These data suggest that LP-BM5 infection is a potential mouse model of HIV-associated distal symmetrical polyneuropathy that can be used for investigating the roles of various cytokines in infection-induced neuropathic pain. Further investigation of this model could give a better understanding of, and lead to more effective treatments for, HIV infection-associated painful peripheral neuropathy. PMID:22956581

  14. Increased levels of myelin basic protein transcripts in virus-induced demyelination.

    PubMed

    Kristensson, K; Holmes, K V; Duchala, C S; Zeller, N K; Lazzarini, R A; Dubois-Dalcq, M

    In multiple sclerosis, a demyelinating disease of young adults, there is a paucity of myelin repair in the central nervous system (CNS) which is necessary for the restoration of fast saltatory conduction in axons. Consequently, this relapsing disease often causes marked disability. In similar diseases of small rodents, however, remyelination can be quite extensive, as in the demyelinating disease caused by the A59 strain of mouse hepatitis virus (MHV-A59), a coronavirus of mice. To investigate when and where oligodendrocytes are first triggered to repair CNS myelin in such disease, we have used a complementary DNA probe specific for one major myelin protein gene, myelin basic protein (MBP), which hybridizes with the four forms of MBP messenger RNA in rodents. Using Northern blot and in situ hybridization techniques, we previously found that MBP mRNA is first detected at about 5 days after birth, peaks at 18 days and progressively decreases to 25% of the peak levels in the adult. We now report that in spinal cord sections of adult animals with active demyelination and inflammatory cells, in situ hybridization reveals a dramatic increase in probe binding to MBP-specific mRNA at 2-3 weeks after virus inoculation and before remyelination can be detected by morphological methods. This increase of MBP-specific mRNA is found at the edge of the demyelinating area and extends into surrounding areas of normal-appearing white matter. Thus, in situ hybridization with myelin-specific probes appears to be a useful method for detecting the timing, intensity and location of myelin protein gene reactivation preceding remyelination. This method could be used to elucidate whether such a reactivation occurs in multiple sclerosis brain tissue. Our results suggest that in mice, glial cells react to a demyelinating process with widespread MBP mRNA synthesis which may be triggered by a diffusible factor released in the demyelinated areas. PMID:2426599

  15. Mechanism of Shope Fibroma Virus-Induced Suppression of Host Deoxyribonucleic Acid Synthesis

    PubMed Central

    Chan, James C.; Hodes, M. E.

    1973-01-01

    The effects of treatment with live or inactivated Shope fibroma virus on host cell deoxyribonucleic acid (DNA) synthesis were determined. The incorporation of 3H-thymidine into nuclear DNA was suppressed by both active and inactivated virus, although live virus was more effective. During the early phase of infection, stimulation of host nuclear DNA synthesis of up to 240% of control value was observed in cells infected with active virus. Inhibition of DNA synthesis began at about the 8th h and was maximal by 12 h postinfection. Virus inactivated by ultraviolet-irradiation or heat treatment did not induce viral DNA synthesis but was, nevertheless, able to suppress host DNA synthesis. PMID:4202660

  16. Promotion of remyelination by polyclonal immunoglobulin in Theiler's virus-induced demyelination and in multiple sclerosis.

    PubMed Central

    van Engelen, B G; Miller, D J; Pavelko, K D; Hommes, O R; Rodriguez, M

    1994-01-01

    Spontaneous remyelination occurs in experimental models of demyelination and in patients with multiple sclerosis, although to a limited extent. This enables the search for factors that promote remyelination. Using the Theiler's virus model of central nervous system demyelination, promotion of remyelination was observed after passive transfer of CNS-specific antiserum and transfer of CNS-specific purified immunoglobulin. Mouse polyclonal immunoglobulin from normal non-syngeneic mice, comparable with the human immunoglobulin preparation, also promotes CNS remyelination in the Theiler's virus model of multiple sclerosis. These experimental findings further bridge the gap with a pilot study that suggests clinical improvement after polyclonal immunoglobulin administration, possibly due to remyelination, in some multiple sclerosis patients with stable, steroid-unresponsive optic neuritis. In view of these experimental and clinical data, the physiological role of myelin in demyelination and remyelination is discussed, and the role of IgG solely as a deleterious molecule in the pathophysiology of multiple sclerosis and experimental demyelination is addressed. PMID:7964859

  17. Varicella-zoster virus induces the formation of dynamic nuclear capsid aggregates

    SciTech Connect

    Lebrun, Marielle; Thelen, Nicolas; Thiry, Marc; Riva, Laura; Ote, Isabelle; Condé, Claude; Vandevenne, Patricia; Di Valentin, Emmanuel; Bontems, Sébastien; Sadzot-Delvaux, Catherine

    2014-04-15

    The first step of herpesviruses virion assembly occurs in the nucleus. However, the exact site where nucleocapsids are assembled, where the genome and the inner tegument are acquired, remains controversial. We created a recombinant VZV expressing ORF23 (homologous to HSV-1 VP26) fused to the eGFP and dually fluorescent viruses with a tegument protein additionally fused to a red tag (ORF9, ORF21 and ORF22 corresponding to HSV-1 UL49, UL37 and UL36). We identified nuclear dense structures containing the major capsid protein, the scaffold protein and maturing protease, as well as ORF21 and ORF22. Correlative microscopy demonstrated that the structures correspond to capsid aggregates and time-lapse video imaging showed that they appear prior to the accumulation of cytoplasmic capsids, presumably undergoing the secondary egress, and are highly dynamic. Our observations suggest that these structures might represent a nuclear area important for capsid assembly and/or maturation before the budding at the inner nuclear membrane. - Highlights: • We created a recombinant VZV expressing the small capsid protein fused to the eGFP. • We identified nuclear dense structures containing capsid and procapsid proteins. • Correlative microscopy showed that the structures correspond to capsid aggregates. • Procapsids and partial capsids are found within the aggregates of WT and eGFP-23 VZV. • FRAP and FLIP experiments demonstrated that they are dynamic structures.

  18. Proteomic Profiling of Human Liver Biopsies: Hepatitis C Virus-Induced Fibrosis and Mitochondrial Dysfunction

    SciTech Connect

    Diamond, Deborah L.; Jacobs, Jon M.; Paeper, Bryan; Proll, Sean; Gritsenko, Marina A.; Carithers, Jr., Robert L.; Larson , Anne M.; Yeh, Matthew M.; Camp, David G.; Smith, Richard D.; Katze, Michael G.

    2007-09-01

    Liver biopsies from HCV-infected patients offer the unique opportunity to study human liver biology and disease in vivo. However, the low protein yields associated with these small samples present a significant challenge for proteomic analysis. In this study we describe the application of an ultra-sensitive proteomics platform for performing robust quantitative proteomic studies on microgram amounts of HCV-infected human liver tissue from 15 patients at different stages of fibrosis. A high quality liver protein data base containing 5,920 unique protein identifications supported high throughput quantitative studies using 16O:18O stable isotope labeling in combination with the accurate mass and time (AMT) tag approach. A total of 1,641 liver biopsy proteins were quantified and ANOVA identified 210 proteins exhibiting statistically significant differences associated with fibrosis stage. Hierarchical clustering revealed that biopsies representative of later fibrosis stages (e.g. Batts-Ludwig stages 3-4) exhibited a distinct protein expression profile indicating an apparent down-regulation of many proteins when compared to samples from earlier fibrosis stages (e.g. Batts-Ludwig stages 0-2). Functional analysis of these signature proteins suggests that impairment of key mitochondrial processes including fatty acid oxidation and oxidative phosphorylation, and response to oxidative stress and reactive oxygen species occurs during advanced stage 3-4 fibrosis. In conclusion, the results reported here represent a significant advancement in clinical proteomics providing to our knowledge, the first demonstration of global proteomic alterations accompanying liver disease progression in patients chronically infected with HCV. Our findings contribute to a generally emerging theme associating oxidative stress and hepatic mitochondrial dysfunction with HCV pathogenesis.

  19. Models of Respiratory Infections: Virus-Induced Asthma Exacerbations and Beyond.

    PubMed

    Saturni, Sara; Contoli, Marco; Spanevello, Antonio; Papi, Alberto

    2015-11-01

    Respiratory infections are one of the main health problems worldwide. They are a challenging field of study due to an intricate relationship between the pathogenicity of microbes and the host's defenses. To better understand mechanisms of respiratory infections, different models have been developed. A model is the reproduction of a disease in a system that mimics human pathophysiology. For this reason, the best models should closely resemble real-life conditions. Thus, the human model is the best. However, human models of respiratory infections have some disadvantages that limit their role. Therefore, other models, including animal, in vitro, and mathematical ones, have been developed. We will discuss advantages and limitations of available models and focus on models of viral infections as triggers of asthma exacerbations, viral infections being one of the most frequent causes of exacerbating disease. Future studies should focus on the interrelation of various models. PMID:26333698

  20. A recombinant pseudotyped lentivirus expressing the envelope glycoprotein of Hantaan virus induced protective immunity in mice

    PubMed Central

    2013-01-01

    Background Hantaviruses cause acute hemorrhagic fever with renal syndrome (HFRS). Currently, several types of inactivated HFRS vaccines are widely used, however the limited ability of these immunogen to elicit neutralizing antibodies restricts vaccine efficacy. Development of an effective vaccine to overcome this weakness is must. Methods In the present study, a recombinant pseudotyped lentivirus bearing the hantaan virus (HTNV) envelope glycoproteins (GP), rLV-M, was constructed. C57BL/6 mice were immunized with the rLV-M and a series of immunological assays were conducted to determine the immunogenicity of the recombinant pseudotyped lentivirus. The humoral and cell-mediated immune responses induced by rLV-M were compared with those of the inactivated HFRS vaccine. Results Indirect immunofluorescence assay (IFA) showed the rLV-M expressed target proteins in HEK-293cells. In mice, the rLV-M efficiently induced GP-specific humoral responses and protection against HTNV infection. Furthermore, the rLV-M induced higher neutralizing antibody titers than the inactivated HFRS vaccine control. Conclusions The results indicated the potential of using a pseudotyped lentivirus as a delivery vector for a hantavirus vaccine immunogen. PMID:24093752

  1. 1, 8-Cineol Protect Against Influenza-Virus-Induced Pneumonia in Mice.

    PubMed

    Li, Yun; Lai, Yanni; Wang, Yao; Liu, Ni; Zhang, Fengxue; Xu, Peiping

    2016-08-01

    1,8-Cineol is a major monoterpene principally from eucalyptus essential oils and has been shown to exert anti-inflammatory, antiviral, and inhibitory of nuclear factor (NF)-kB effect. In the present study, we evaluated the effect of 1,8-cineol on mice infected with influenza A virus. We found that 1,8-cineol protects against influenza viral infection in mice. Moreover, 1,8-cineol efficiently decreased the level of IL-4, IL-5, IL-10, and MCP-1 in nasal lavage fluids and the level of IL-1β, IL-6, TNF-α, and IFN-γ in lung tissues of mice infected with influenza virus. The results also showed that 1,8-cineol reduced the expression of NF-kB p65, intercellular adhesion molecule (ICAM)-1, and vascular cell adhesion molecule (VCAM)-1 in lung tissues. Thus, 1,8-cineol appears to be able to augment protection against IFV infection in mice via attenuation of pulmonary inflammatory responses. PMID:27351430

  2. Rapid Determination of Gene Function by Virus-Induced Gene Silencing in Wheat and Barley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cereal crops are essential components to the human and animal food supply. Solutions to many of the problems challenging cereal production will require identification of genes responsible for particular traits. Unfortunately, the process of identifying gene function is very slow and complex in ...

  3. Neurovirulent simian immunodeficiency virus induces calbindin-D-28K in astrocytes.

    PubMed

    Berman, N E; Yong, C; Raghavan, R; Raymond, L A; Joag, S V; Narayan, O; Cheney, P D

    1998-05-01

    Astrocyte activation has been postulated to be a major contributor to functional changes in the brain of AIDS patients. We assessed astrocyte activation in the simian immunodeficiency virus (SIV) model. Four groups of macaque brains were examined: uninoculated controls, animals inoculated with virus that did not cause disease, animals inoculated with virus that caused AIDS but did not cause encephalitis, and animals with SIV encephalitis. We examined expression of calbindin-D-28K, a calcium binding protein that is upregulated in astrocytes during excitotoxic events, as well as glial fibrillary acidic protein (GFAP). The presence of calbindin in astrocytes was confirmed by double-labeling using confocal microscopy. Increases in calbindin staining were most apparent in the white matter, but increases in GFAP staining were most apparent in middle layers of the cerebral cortex. Six of the seven animals with SIV encephalitis had calbindin immunoreactive astrocytes in the subcortical white matter, corpus callosum, internal capsule, cerebral peduncle, pontine white matter, and cerebellar white matter. Very rarely, a few, very lightly calbindin-immunoreactive astrocytes were present in the uninoculated control brains. The increase in calbindin expression by astrocytes in SIV encephalitis suggests that these cells are subject to calcium toxicity. In uninoculated control macaques, and in macaques inoculated with virus that did not cause disease, GFAP-immunoreactive astrocytes were present throughout the subcortical white matter and in layer I, but very few were found in layers III-V of the cerebral cortex. Two animals that died of AIDS without encephalitis had somewhat higher numbers of GFAP immunoreactive astrocytes in middle cortical layers. In seven animals that received passaged neurovirulent virus and developed both AIDS and encephalitis, the number of GFAP-immunoreactive astrocytes in middle cortical layers was high, indicating widespread astrocyte activation. PMID:9778644

  4. Inhibition of Nox2 Oxidase Activity Ameliorates Influenza A Virus-Induced Lung Inflammation

    PubMed Central

    Bozinovski, Steven; Broughton, Brad R. S.; Drummond, Grant R.; Selemidis, Stavros

    2011-01-01

    Influenza A virus pandemics and emerging anti-viral resistance highlight the urgent need for novel generic pharmacological strategies that reduce both viral replication and lung inflammation. We investigated whether the primary enzymatic source of inflammatory cell ROS (reactive oxygen species), Nox2-containing NADPH oxidase, is a novel pharmacological target against the lung inflammation caused by influenza A viruses. Male WT (C57BL/6) and Nox2−/y mice were infected intranasally with low pathogenicity (X-31, H3N2) or higher pathogenicity (PR8, H1N1) influenza A virus. Viral titer, airways inflammation, superoxide and peroxynitrite production, lung histopathology, pro-inflammatory (MCP-1) and antiviral (IL-1β) cytokines/chemokines, CD8+ T cell effector function and alveolar epithelial cell apoptosis were assessed. Infection of Nox2−/y mice with X-31 virus resulted in a significant reduction in viral titers, BALF macrophages, peri-bronchial inflammation, BALF inflammatory cell superoxide and lung tissue peroxynitrite production, MCP-1 levels and alveolar epithelial cell apoptosis when compared to WT control mice. Lung levels of IL-1β were ∼3-fold higher in Nox2−/y mice. The numbers of influenza-specific CD8+DbNP366+ and DbPA224+ T cells in the BALF and spleen were comparable in WT and Nox2−/y mice. In vivo administration of the Nox2 inhibitor apocynin significantly suppressed viral titer, airways inflammation and inflammatory cell superoxide production following infection with X-31 or PR8. In conclusion, these findings indicate that Nox2 inhibitors have therapeutic potential for control of lung inflammation and damage in an influenza strain-independent manner. PMID:21304882

  5. Dermatitis herpetiformis sera or goat anti-transglutaminase-3 transferred to human skin-grafted mice mimics dermatitis herpetiformis immunopathology.

    PubMed

    Zone, John J; Schmidt, Linda A; Taylor, Ted B; Hull, Christopher M; Sotiriou, Michael C; Jaskowski, Troy D; Hill, Harry R; Meyer, Laurence J

    2011-04-01

    Dermatitis herpetiformis (DH) is characterized by deposition of IgA in the papillary dermis. However, indirect immunofluorescence is routinely negative, raising the question of the mechanism of formation of these immune deposits. Sárdy et al. (2002. J. Exp. Med. 195: 747-757) reported that transglutaminase-3 (TG3) colocalizes with the IgA. We sought to create such deposits using passive transfer of Ab to SCID mice bearing human skin grafts. IgG fraction of goat anti-TG3 or control IgG were administered i.p. to 20 mice. Separately, sera from seven DH patients and seven controls were injected intradermally. Biopsies were removed and processed for routine histology as well as direct immunofluorescence. All mice that received goat anti-TG3 produced papillary dermal immune deposits, and these deposits reacted with both rabbit anti-TG3 and DH patient sera. Three DH sera high in IgA anti-TG3 also produced deposits of granular IgA and TG3. We hypothesize that the IgA class anti-TG3 Abs are directly responsible for the immune deposits and that the TG3 is from human epidermis, as this is its only source in our model. These deposits seem to form over weeks in a process similar to an Ouchterlony immunodiffusion precipitate. This process of deposition explains the negative indirect immunofluorescence results with DH serum. PMID:21335491

  6. Clinical significance of immunopathological findings in patients with post-pericardiotomy syndrome. I. Relevance of antibody pattern

    PubMed Central

    Maisch, B.; Berg, P. A.; Kochsiek, K.

    1979-01-01

    Sera from sixty-five patients were collected before and after cardiac surgery to determine striated muscle antibodies (anti-heart and anti-skeletal), non-organ-specific antibodies, immunoglobulin and complement levels. According to the clinical features of pericarditis, fever and leucocytosis, patients were divided into three groups: (1) complete post-pericardotomy syndrome (PPS) (n = 19) with all three symptoms; (2) incomplete PPS with two symptoms (n = 18); and (3) no PPS with one or no symtpoms (n = 28). Almost all the patients with complete PPS, two thirds of the patients with incomplete PPS and one third of the patients with no PPS showed striated muscle antibodies. Anti-sarcolemmal antibodies predominated. In patients with complete PPS, antibodies persisted beyond the fourth post-operative week and correlated well with symptoms. An even better correlation with the syndrome could be obtained by including the post-operative occurrence of anti-endothelial (AEA), smooth muscle (SMA), the pre- and post-operative frequency of antinuclear antibodies (ANA) and the increase in immunoglobulin concentrations after surgery in an immunological grading system. These criteria permitted a redistribution of the nineteen patients with an incomplete PPS: fourteen were immunologically positive for a PPS. Although autoantibodies are predominantly associated with PPS, their role in the pathogenesis of the syndrome is not clear. The complementary influence of surgical and non-surgical factors, such as the degree of myocardial damage, the time of ischemia during the operation and a possible viral infection by blood transfusion, is analysed. PMID:527258

  7. Dengue encephalitis-associated immunopathology in the mouse model: Implications for vaccine developers and antigens inducer of cellular immune response.

    PubMed

    Marcos, Ernesto; Lazo, Laura; Gil, Lázaro; Izquierdo, Alienys; Suzarte, Edith; Valdés, Iris; Blanco, Aracelys; Ancizar, Julio; Alba, José Suárez; Pérez, Yusleydis de la C; Cobas, Karen; Romero, Yaremis; Guillén, Gerardo; Guzmán, María G; Hermida, Lisset

    2016-08-01

    Despite the many efforts made by the scientific community in the development of vaccine candidates against dengue virus (DENV), no vaccine has been licensed up to date. Although the immunopathogenesis associated to the disease is a key factor to take into account by vaccine developers, the lack of animal models that reproduce the clinical signs of the disease has hampered the vaccine progress. Non-human primates support viral replication, but they are very expensive and do not show signs of disease. Immunocompromised mice develop viremia and some signs of the disease; however, they are not valuable for vaccine testing. Nowadays, immunocompetent mice are the most used model to evaluate the immunogenicity of vaccine candidates. These animals are resistant to DENV infection; therefore, the intracranial inoculation with neuroadapted virus, which provokes viral encephalitis, represents an alternative to evaluate the protective capacity of vaccine candidates. Previous results have demonstrated the crucial role of cellular immune response in the protection induced by the virus and vaccine candidates in this mouse encephalitis model. However, in the present work we are proposing that the magnitude of the cell-mediated immunity and the inflammatory response generated by the vaccine can modulate the survival rate after viral challenge. We observed that the intracranial challenge of naïve mice with DENV-2 induces the recruitment of immune cells that contribute to the reduction of viral load, but does not increase the survival rate. On the contrary, animals treated with cyclophosphamide, an immunosuppressive drug that affects proliferating lymphocytes, had a higher viral load but a better survival rate than untreated animals. These results suggest that the immune system is playing an immunopathogenic role in this model and the survival rate may not be a suitable endpoint in the evaluation of vaccine candidates based on antigens that induce a strong cellular immune response. PMID:27233365

  8. Blockage of Galectin-receptor Interactions by α-lactose Exacerbates Plasmodium berghei-induced Pulmonary Immunopathology

    PubMed Central

    Liu, Jinfeng; Huang, Shiguang; Su, Xin-zhuan; Song, Jianping; Lu, Fangli

    2016-01-01

    Malaria-associated acute lung injury (ALI) is a frequent complication of severe malaria that is often caused by “excessive” immune responses. To better understand the mechanism of ALI in malaria infection, here we investigated the roles of galectin (Gal)-1, 3, 8, 9 and the receptors of Gal-9 (Tim-3, CD44, CD137, and PDI) in malaria-induced ALI. We injected alpha (α)-lactose into mice-infected with Plasmodium berghei ANKA (PbANKA) to block galectins and found significantly elevated total proteins in bronchoalveolar lavage fluid, higher parasitemia and tissue parasite burden, and increased numbers of CD68+ alveolar macrophages as well as apoptotic cells in the lungs after blockage. Additionally, mRNA levels of Gal-9, Tim-3, CD44, CD137, and PDI were significantly increased in the lungs at day 5 after infection, and the levels of CD137, IFN-α, IFN-β, IFN-γ, IL-4, and IL-10 in the lungs were also increased after α-lactose treatment. Similarly, the levels of Gal-9, Tim-3, IFN-α, IFN-β, IFN-γ, and IL-10 were all significantly increased in murine peritoneal macrophages co-cultured with PbANKA-infected red blood cells in vitro; but only IFN-α and IFN-β were significantly increased after α-lactose treatment. Our data indicate that Gal-9 interaction with its multiple receptors play an important role in murine malaria-associated ALI. PMID:27554340

  9. Type 1 reaction in leprosy: a model for a better understanding of tissue immunity under an immunopathological condition.

    PubMed

    Andrade, Priscila Ribeiro; Pinheiro, Roberta Olmo; Sales, Anna Maria; Illarramendi, Ximena; Barbosa, Mayara Garcia de Mattos; Moraes, Milton Ozório; Jardim, Marcia Rodrigues; Nery, Jose Augusto da Costa; Sampaio, Elizabeth Pereira; Sarno, Euzenir Nunes

    2015-03-01

    Type 1 reaction (T1R) or reversal reaction is the leading cause of physical disabilities and deformities in leprosy. Leprosy patients, even after being considered cured and released from treatment, may suffer from reactional episodes for long periods of time. Early diagnosis is a great challenge for effectively treating and managing T1R. There is an urgent need to identify the most significant biomarkers to prevent recurrent T1R and to differentiate late T1R from relapse. T1R continues to be treated with corticosteroids and complications due to iatrogenic treatment remain frequent. This review aims to provide a framework from which to approach the great challenges that still persist in T1R management and debate key issues in order to reduce the distance between basic research and the clinic. PMID:25666357

  10. Myxoid angioblastomatosis of bones. A case report of a rare, multifocal entity with light, ultramicroscopic, and immunopathologic correlation.

    PubMed

    Mirra, J M; Kameda, N

    1985-06-01

    An example of multicentric, skeletal, myxoid angioblastomas in a Japanese woman is reported. The disease was symptomatic at age 12 years and was characterized by slowly progressive, multiple, lytic bone defects. In addition the patient had juvenile hypertension, and, at age 20 years, had focal brain infarction. The primitive vascular nature of the process was supported by the following observations: occasional erythrocytes within cytoplasmic lumina and capillary-like cellular tubes; Weibel-Palade bodies, numerous pinocytotic vesicles, prominent microvilli, elaborate intercellular contacts, desmosomes, and numerous arrays of fine intracytoplasmic filaments by electron microscopy; and, in addition, Factor VIII positivity. The clinical findings in this case are more consistent with a multicentric, rather than a metastatic process. The name myxoid angioblastomatosis of bones is appropriate. PMID:4091181

  11. Blockage of Galectin-receptor Interactions by α-lactose Exacerbates Plasmodium berghei-induced Pulmonary Immunopathology.

    PubMed

    Liu, Jinfeng; Huang, Shiguang; Su, Xin-Zhuan; Song, Jianping; Lu, Fangli

    2016-01-01

    Malaria-associated acute lung injury (ALI) is a frequent complication of severe malaria that is often caused by "excessive" immune responses. To better understand the mechanism of ALI in malaria infection, here we investigated the roles of galectin (Gal)-1, 3, 8, 9 and the receptors of Gal-9 (Tim-3, CD44, CD137, and PDI) in malaria-induced ALI. We injected alpha (α)-lactose into mice-infected with Plasmodium berghei ANKA (PbANKA) to block galectins and found significantly elevated total proteins in bronchoalveolar lavage fluid, higher parasitemia and tissue parasite burden, and increased numbers of CD68(+) alveolar macrophages as well as apoptotic cells in the lungs after blockage. Additionally, mRNA levels of Gal-9, Tim-3, CD44, CD137, and PDI were significantly increased in the lungs at day 5 after infection, and the levels of CD137, IFN-α, IFN-β, IFN-γ, IL-4, and IL-10 in the lungs were also increased after α-lactose treatment. Similarly, the levels of Gal-9, Tim-3, IFN-α, IFN-β, IFN-γ, and IL-10 were all significantly increased in murine peritoneal macrophages co-cultured with PbANKA-infected red blood cells in vitro; but only IFN-α and IFN-β were significantly increased after α-lactose treatment. Our data indicate that Gal-9 interaction with its multiple receptors play an important role in murine malaria-associated ALI. PMID:27554340

  12. The Th1/Th2 cytokine balance changes with the progress of the immunopathological lesion of Sjogren’s syndrome

    PubMed Central

    MITSIAS, D I; TZIOUFAS, A G; VEIOPOULOU, C; ZINTZARAS, E; TASSIOS, I K; KOGOPOULOU, O; MOUTSOPOULOS, H M; THYPHRONITIS, G

    2002-01-01

    Expression of type-1 and type-2 cytokines at the mRNA level in labial salivary glands (LSG) of patients with Sjogren’s syndrome (SS), as reported by several groups, have generated conflicting results. In the present study we have directly examined the production of IL-4, IL-13 and IFN-γ by lymphocytes infiltrating the LSG of 44 consecutive patients referred for SS evaluation. Cytokines production was evaluated following in vitro culture of LSG in the presence of IL-2. IFN-γ and IL-13 were detected in the majority of SN (24/44 and 26/44, respectively) while IL-4 was present in 5/44 SN. The presence of IFN-γ was significantly higher in SS patients, as opposed to patients who did not fulfil the criteria for SS (P < 0·01). In addition, almost all cultured lymphocytes expressed mRNA for IFN-γ (17/19 cultures) and IL-13 (18/19) while IL-4 mRNA was also expressed at high frequency (14/19 cultures). Interestingly, the IFN-γ mRNA copies in cultured lymphocytes correlated significantly with the intensity of lymphocytic infiltration as evaluated by Chisholm’s score (P < 0·01). Furthermore, RT-PCR of RNA extracted from whole LSG from 14 SS patients also demonstrated the presence of all cytokines in the majority of the cases and the prevalence of IFN-γ in LSG with high-grade infiltration. Because IL-13 was produced by the majority of the cultured LSG, IgE production was also evaluated. Interestingly, IgE was detected in 21/44 LSG culture SN and mainly in those biopsies that had Chisholm’s score less than 0·5 (P < 0·05). We conclude that lymphocytes infiltrating the LSG are capable of producing both Th1 and Th2 cytokines and that the balance between them shifts in favour of Th1 in LSG with high infiltration score and in patients with SS. PMID:12067313

  13. Killer Cell Immunoglobulin-like Receptors and Their HLA Ligands are Related with the Immunopathology of Chagas Disease

    PubMed Central

    Ayo, Christiane Maria; Reis, Pâmela Guimarães; Dalalio, Márcia Machado de Oliveira; Visentainer, Jeane Eliete Laguila; Oliveira, Camila de Freitas; de Araújo, Silvana Marques; de Oliveira Marques, Divina Seila; Sell, Ana Maria

    2015-01-01

    The aim of this study was to investigate the influence of killer cell immunoglobulin-like receptor (KIR) genes and their human leucocyte antigen (HLA) ligands in the susceptibility of chronic Chagas disease. This case-control study enrolled 131 serologically-diagnosed Chagas disease patients (59 men and 72 women, mean age of 60.4 ± 9.8 years) treated at the University Hospital of Londrina and the Chagas Disease Laboratory of the State University of Maringa. A control group was formed of 165 healthy individuals - spouses of patients or blood donors from the Regional Blood Bank in Maringa (84 men and 81 women, with a mean age of 59.0 ± 11.4 years). Genotyping of HLA and KIR was performed by PCR-SSOP. KIR2DS2-C1 in the absence of KIR2DL2 (KIR2DS2+/2DL2-/C1+) was more frequent in Chagas patients (P = 0.020; Pc = 0.040; OR = 2.14) and, in particular, those who manifested chronic chagasic cardiopathy—CCC (P = 0.0002; Pc = 0.0004; OR = 6.64; 95% CI = 2.30–18.60) when compared to the control group, and when CCC group was compared to the patients without heart involvement (P = 0.010; Pc = 0.020; OR = 3.97). The combination pair KIR2DS2+/2DL2-/KIR2DL3+/C1+ was also positively associated with chronic chagasic cardiopathy. KIR2DL2 and KIR2DS2 were related to immunopathogenesis in Chagas disease. The combination of KIR2DS2 activating receptor with C1 ligand, in the absence of KIR2DL2, may be related to a risk factor in the chronic Chagas disease and chronic chagasic cardiopathy. PMID:25978047

  14. [Influence of GABA derivatives on some indices of lipid peroxidation in immunocompetent organs under experimental immunopathology conditions].

    PubMed

    Samotrueva, M A; Magomedov, M M; Khlebtsova, E B; Tiurenkov, I N

    2011-01-01

    The effects of GABA derivatives phenotropil (25 mg/kg), phenibut (25 mg/kg), and baclofen (2 mg/kg) on the process of lipid peroxidation (LPO), as manifested by the initial level of malonic dialdehyde, velocity of spontaneous and ascorbate-dependent LPO, and the catalase activity in the homogenates of thymus and spleen, have been studied on rats of the Wistar line with cyclophosphamide (CPHA) immunodepression and lipopolysacharide (LPS) immune stress. It is established that, under the action of CPHA and LPS, activation of the LPO processes takes place in the immune organs. Under these conditions, changes of the catalase activity exhibited some specific features: in the animals under LPS action, the catalase activity increased in the spleen, while being decreased in the thymus; under the influence of CPHA, the activity of this enzyme decreased in both organs. An analysis of the antioxidant activity of GABA derivatives under the conditions of CPHA-induced immunodepression showed that all substances upon intraperitoneal introduction for 5 days favored the elimination of disturbances by suppressing the LPO processes and increasing the antioxidant protection activity. On the background of LPS-induced immune stress, all the tested substances showed a correcting action with respect to indicated biochemical processes in the thymus, while only phenibut activated the antioxidant system in the spleen. PMID:22232912

  15. Focal Nodular Hyperplasia and Hepatocellular Adenoma around the World Viewed through the Scope of the Immunopathological Classification

    PubMed Central

    Al-Rabih, Wesal R.; Chen, Pei-Jer; Evason, Kimberley; Ferrell, Linda; Hernandez-Prera, Juan C.; Huang, Shiu-Feng; Longerich, Thomas; Park, Young Nyun; Quaglia, Alberto; Schirmacher, Peter; Sempoux, Christine; Thung, Swan N.; Torbenson, Michael; Wee, Aileen; Yeh, Matthew M.; Yeh, Shiou-Hwei; Le Bail, Brigitte; Zucman-Rossi, Jessica; Bioulac-Sage, Paulette

    2013-01-01

    Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are benign hepatocellular tumors. The risk of bleeding and malignant transformation of HCA are strong arguments to differentiate HCA from FNH. Despite great progress that has been made in the differential radiological diagnosis of the 2 types of nodules, liver biopsy is sometimes necessary to separate the 2 entities. Identification of HCA subtypes using immunohistochemical techniques, namely, HNF1A-inactivated HCA (35–40%), inflammatory HCA (IHCA), and beta-catenin-mutated inflammatory HCA (b-IHCA) (50–55%), beta-catenin-activated HCA (5–10%), and unclassified HCA (10%) has greatly improved the diagnostic accuracy of benign hepatocellular nodules. If HCA malignant transformation occurs in all HCA subgroups, the risk is by far the highest in the β-catenin-mutated subgroups (b-HCA, b-IHCA). In the coming decade the management of HCA will be more dependent on the identification of HCA subtypes, particularly for smaller nodules (<5 cm) in terms of imaging, follow-up, and resection. PMID:23691331

  16. Immuno-pathological studies on broiler chicken experimentally infected with Escherichia coli and supplemented with neem (Azadirachta indica) leaf extract

    PubMed Central

    Sharma, Vikash; Jakhar, K. K.; Dahiya, Swati

    2016-01-01

    Aim: The present study was conducted to evaluate the effects of neem leaf extract (NLE) supplementation on immunological response and pathology of different lymphoid organs in experimentally Escherichia coli challenged broiler chickens. Materials and Methods: For this study, we procured 192-day-old broiler chicks from local hatchery and divided them into Groups A and Group B containing 96 birds each on the first day. Chicks of Group A were supplemented with 10% NLE in water, whereas chicks of Group B were not supplemented with NLE throughout the experiment. At 7th day of age, chicks of Group A were divided into A1 and A2 and Group B into B1 and B2 with 54 and 42 chicks, respectively, and chicks of Groups A1 and B1 were injected with E. coli O78 at 107 colony-forming units/0.5 ml intraperitoneally. Six chicks from each group were sacrificed at 0, 2, 4, 7, 14, 21, and 28 days post infection; blood was collected and thorough post-mortem examination was conducted. Tissue pieces of spleen and bursa of Fabricius were collected in 10% buffered formalin for histopathological examination. Serum was separated for immunological studies. Result: E. coli specific antibody titer was significantly higher in Group A1 in comparison to Group B1. Delayed-type hypersensitivity response against 2,4 dinirochlorobenzene (DNCB) antigen was significantly higher in Group A1 as compared to Group B1. Pathological studies revealed that E. coli infection caused depletion of lymphocytes in bursa of Fabricius and spleen. Severity of lesions in Group A1 was significantly lower in comparison to Group B1. Conclusion: 10% NLE supplementation enhanced the humoral as well as cellular immune responses attributed to its immunomodulatory property in experimentally E. coli infected broiler chicken. PMID:27536035

  17. Alcohol intake alters immune responses and promotes CNS viral persistence in mice.

    PubMed

    Loftis, Jennifer M; Taylor, Jonathan; Raué, Hans-Peter; Slifka, Mark K; Huang, Elaine

    2016-10-01

    Chronic hepatitis C virus (HCV) infection leads to progressive liver disease and is associated with a variety of extrahepatic effects, including central nervous system (CNS) damage and neuropsychiatric impairments. Alcohol abuse can exacerbate these adverse effects on brain and behavior, but the molecular mechanisms are not well understood. This study investigated the role of alcohol in regulating viral persistence and CNS immunopathology in mice infected with lymphocytic choriomeningitis virus (LCMV), a model for HCV infections in humans. Female and male BALB/c mice (n=94) were exposed to alcohol (ethanol; EtOH) and water (or water only) using a two-bottle choice paradigm, followed one week later by infection with either LCMV clone 13 (causes chronic infection similar to chronic HCV), LCMV Armstrong (causes acute infection), or vehicle. Mice were monitored for 60days post-infection and continued to receive 24-h access to EtOH and water. Animals infected with LCMV clone 13 drank more EtOH, as compared to those with an acute or no viral infection. Six weeks after infection with LCMV clone 13, mice with EtOH exposure evidenced higher serum viral titers, as compared to mice without EtOH exposure. EtOH intake was also associated with reductions in virus-specific CD8(+) T cell frequencies (particularly CD11a(hi) subsets) and evidence of persistent CNS viremia in chronically infected mice. These findings support the hypothesis that EtOH use and chronic viral infection can result in combined toxic effects accelerating CNS damage and neuropsychiatric dysfunction and suggest that examining the role of EtOH in regulating viral persistence and CNS immunopathology in mice infected with LCMV can lead to a more comprehensive understanding of comorbid alcohol use disorder and chronic viral infection. PMID:27269869

  18. Programmed death 1 protects from fatal circulatory failure during systemic virus infection of mice

    PubMed Central

    Frebel, Helge; Nindl, Veronika; Schuepbach, Reto A.; Braunschweiler, Thomas; Richter, Kirsten; Vogel, Johannes; Wagner, Carsten A.; Loffing-Cueni, Dominique; Kurrer, Michael; Ludewig, Burkhard

    2012-01-01

    The inhibitory programmed death 1 (PD-1)–programmed death ligand 1 (PD-L1) pathway contributes to the functional down-regulation of T cell responses during persistent systemic and local virus infections. The blockade of PD-1–PD-L1–mediated inhibition is considered as a therapeutic approach to reinvigorate antiviral T cell responses. Yet previous studies reported that PD-L1–deficient mice develop fatal pathology during early systemic lymphocytic choriomeningitis virus (LCMV) infection, suggesting a host protective role of T cell down-regulation. As the exact mechanisms of pathology development remained unclear, we set out to delineate in detail the underlying pathogenesis. Mice deficient in PD-1–PD-L1 signaling or lacking PD-1 signaling in CD8 T cells succumbed to fatal CD8 T cell–mediated immunopathology early after systemic LCMV infection. In the absence of regulation via PD-1, CD8 T cells killed infected vascular endothelial cells via perforin-mediated cytolysis, thereby severely compromising vascular integrity. This resulted in systemic vascular leakage and a consequential collapse of the circulatory system. Our results indicate that the PD-1–PD-L1 pathway protects the vascular system from severe CD8 T cell–mediated damage during early systemic LCMV infection, highlighting a pivotal physiological role of T cell down-regulation and suggesting the potential development of immunopathological side effects when interfering with the PD-1–PD-L1 pathway during systemic virus infections. PMID:23230000

  19. Inoculation of swine with foot-and-mouth disease SAP-mutant virus induces early protection against disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foot-and-mouth disease virus (FMDV) leader proteinase (L^pro) cleaves itself from the viral polyprotein and cleaves the translation initiation factor eIF4G. As a result, host cell translation is inhibited, affecting the host innate immune response. We have demonstrated that L^pro is also associated ...

  20. The Role of B Cells for in Vivo T Cell Responses to a Friend Virus-Induced Leukemia

    NASA Astrophysics Data System (ADS)

    Schultz, Kirk R.; Klarnet, Jay P.; Gieni, Randall S.; Hayglass, Kent T.; Greenberg, Philip D.

    1990-08-01

    B cells can function as antigen-presenting cells and accessory cells for T cell responses. This study evaluated the role of B cells in the induction of protective T cell immunity to a Friend murine leukemia virus (F-MuLV)-induced leukemia (FBL). B cell-deficient mice exhibited significantly reduced tumor-specific CD4^+ helper and CD8^+ cytotoxic T cell responses after priming with FBL or a recombinant vaccinia virus containing F-MuLV antigens. Moreover, these mice had diminished T cell responses to the vaccinia viral antigens. Tumor-primed T cells transferred into B cell-deficient mice effectively eradicated disseminated FBL. Thus, B cells appear necessary for efficient priming but not expression of tumor and viral T cell immunity.

  1. Canarypox Virus-Induced Maturation of Dendritic Cells Is Mediated by Apoptotic Cell Death and Tumor Necrosis Factor Alpha Secretion

    PubMed Central

    Ignatius, Ralf; Marovich, Mary; Mehlhop, Erin; Villamide, Loreley; Mahnke, Karsten; Cox, William I.; Isdell, Frank; Frankel, Sarah S.; Mascola, John R.; Steinman, Ralph M.; Pope, Melissa

    2000-01-01

    Recombinant avipox viruses are being widely evaluated as vaccines. To address how these viruses, which replicate poorly in mammalian cells, might be immunogenic, we studied how canarypox virus (ALVAC) interacts with primate antigen-presenting dendritic cells (DCs). When human and rhesus macaque monocyte-derived DCs were exposed to recombinant ALVAC, immature DCs were most susceptible to infection. However, many of the infected cells underwent apoptotic cell death, and dying infected cells were engulfed by uninfected DCs. Furthermore, a subset of DCs matured in the ALVAC-exposed DC cultures. DC maturation coincided with tumor necrosis factor alpha (TNF-α) secretion and was significantly blocked in the presence of anti-TNF-α antibodies. Interestingly, inhibition of apoptosis with a caspase 3 inhibitor also reduced some of the maturation induced by exposure to ALVAC. This indicates that both TNF-α and the presence of primarily apoptotic cells contributed to DC maturation. Therefore, infection of immature primate DCs with ALVAC results in apoptotic death of infected cells, which can be internalized by noninfected DCs driving DC maturation in the presence of the TNF-α secreted concomitantly by exposed cells. This suggests an important mechanism that may influence the immunogenicity of avipox virus vectors. PMID:11070033

  2. Virus-induced gene silencing of WRKY53 and an inducible phenylalanine ammonia-lyase in wheat reduces aphid resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although several wheat genes differentially expressed during the Russian wheat aphid resistance response have recently been identified, their requirement for and specific role in resistance remain unclear. Progress in wheat-aphid interaction research is hampered by inadequate collections of mutant g...

  3. Exome capture sequencing reveals new insights into hepatitis B virus-induced hepatocellular carcinoma at the early stage of tumorigenesis.

    PubMed

    Chen, Yong; Wang, Lijuan; Xu, Hexiang; Liu, Xingxiang; Zhao, Yingren

    2013-10-01

    Hepatocellular carcinoma (HCC), the most common type of liver cancer, is the third primary cause of cancer-related mortality worldwide. The molecular mechanisms underlying the initiation and formation of HCC remain obscure. In the present study, we performed exome sequencing using tumor and normal tissues from 3 hepatitis B virus (HBV)-positive BCLC stage A HCC patients. Bioinformatic analysis was performed to find candidate protein-altering somatic mutations. Eighty damaging mutations were validated and 59 genes were reported to be mutated in HBV-related HCCs for the first time here. Further analysis using whole genome sequencing (WGS) data of 88 HBV-related HCC patients from the European Genome-phenome Archive database showed that mutations in 33 of the 59 genes were also detected in other samples. Variants of two newly found genes, ZNF717 and PARP4, were detected in more than 10% of the WGS samples. Several other genes, such as FLNA and CNTN2, are also noteworthy. Thus, the exome sequencing analysis of three BCLC stage A patients provides new insights into the molecular events governing the early steps of HBV-induced HCC tumorigenesis. PMID:23912677

  4. Apocynin and ebselen reduce influenza A virus-induced lung inflammation in cigarette smoke-exposed mice

    PubMed Central

    Oostwoud, L. C.; Gunasinghe, P.; Seow, H. J.; Ye, J. M.; Selemidis, S.; Bozinovski, S.; Vlahos, R.

    2016-01-01

    Influenza A virus (IAV) infections are a common cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Oxidative stress is increased in COPD, IAV-induced lung inflammation and AECOPD. Therefore, we investigated whether targeting oxidative stress with the Nox2 oxidase inhibitors and ROS scavengers, apocynin and ebselen could ameliorate lung inflammation in a mouse model of AECOPD. Male BALB/c mice were exposed to cigarette smoke (CS) generated from 9 cigarettes per day for 4 days. On day 5, mice were infected with 1 × 104.5 PFUs of the IAV Mem71 (H3N1). BALF inflammation, viral titers, superoxide production and whole lung cytokine, chemokine and protease mRNA expression were assessed 3 and 7 days post infection. IAV infection resulted in a greater increase in BALF inflammation in mice that had been exposed to CS compared to non-smoking mice. This increase in BALF inflammation in CS-exposed mice caused by IAV infection was associated with elevated gene expression of pro-inflammatory cytokines, chemokines and proteases, compared to CS alone mice. Apocynin and ebselen significantly reduced the exacerbated BALF inflammation and pro-inflammatory cytokine, chemokine and protease expression caused by IAV infection in CS mice. Targeting oxidative stress using apocynin and ebselen reduces IAV-induced lung inflammation in CS-exposed mice and may be therapeutically exploited to alleviate AECOPD. PMID:26877172

  5. Conserved peptides within the E2 region of Hepatitis C virus induce humoral and cellular responses in goats

    PubMed Central

    El-Awady, Mostafa K; Tabll, Ashraf A; El-Abd, Yasmine S; Yousif, Hassan; Hegab, Mohsen; Reda, Mohamed; El Shenawy, Reem; Moustafa, Rehab I; Degheidy, Nabila; El Din, Noha G Bader

    2009-01-01

    The reason(s) why human antibodies raised against hepatitis C virus (HCV) E2 epitopes do not offer protection against multiple viral infections may be related to either genetic variations among viral strains particularly within the hypervariable region-1 (HVR-1), low titers of anti E2 antibodies or interference of non neutralizing antibodies with the function of neutralizing antibodies. This study was designed to assess the immunogenic properties of genetically conserved peptides derived from the C-terminal region of HVR-1 as potential therapeutic and/or prophylactic vaccines against HCV infection. Goats immunized with E2-conserved synthetic peptides termed p36 (a.a 430–446), p37(a.a 517–531) and p38 (a.a 412–419) generated high titers of anti-p36, anti-p37 and anti-P38 antibody responses of which only anti- p37 and anti- p38 were neutralizing to HCV particles in sera from patients infected predominantly with genotype 4a. On the other hand anti-p36 exhibited weak viral neutralization capacity on the same samples. Animals super-immunized with single epitopes generated 2 to 4.5 fold higher titers than similar antibodies produced in chronic HCV patients. Also the studied peptides elicited approximately 3 fold increase in cell proliferation of specific antibody-secreting peripheral blood mononuclear cells (PBMC) from immunized goats. These results indicate that, besides E1 derived peptide p35 (a.a 315–323) described previously by this laboratory, E2 conserved peptides p37 and p38 represent essential components of a candidate peptide vaccine against HCV infection. PMID:19473491

  6. Molecular Biology, Epidemiology, and Pathogenesis of Progressive Multifocal Leukoencephalopathy, the JC Virus-Induced Demyelinating Disease of the Human Brain

    PubMed Central

    Ferenczy, Michael W.; Marshall, Leslie J.; Nelson, Christian D. S.; Atwood, Walter J.; Nath, Avindra; Khalili, Kamel

    2012-01-01

    Summary: Progressive multifocal leukoencephalopathy (PML) is a debilitating and frequently fatal central nervous system (CNS) demyelinating disease caused by JC virus (JCV), for which there is currently no effective treatment. Lytic infection of oligodendrocytes in the brain leads to their eventual destruction and progressive demyelination, resulting in multiple foci of lesions in the white matter of the brain. Before the mid-1980s, PML was a relatively rare disease, reported to occur primarily in those with underlying neoplastic conditions affecting immune function and, more rarely, in allograft recipients receiving immunosuppressive drugs. However, with the onset of the AIDS pandemic, the incidence of PML has increased dramatically. Approximately 3 to 5% of HIV-infected individuals will develop PML, which is classified as an AIDS-defining illness. In addition, the recent advent of humanized monoclonal antibody therapy for the treatment of autoimmune inflammatory diseases such as multiple sclerosis (MS) and Crohn's disease has also led to an increased risk of PML as a side effect of immunotherapy. Thus, the study of JCV and the elucidation of the underlying causes of PML are important and active areas of research that may lead to new insights into immune function and host antiviral defense, as well as to potential new therapies. PMID:22763635

  7. Virus-Neutralizing Monoclonal Antibody Expressed in Milk of Transgenic Mice Provides Full Protection against Virus-Induced Encephalitis

    PubMed Central

    Kolb, Andreas F.; Pewe, Lecia; Webster, John; Perlman, Stanley; Whitelaw, C. Bruce A.; Siddell, Stuart G.

    2001-01-01

    Neutralizing antibodies represent a major host defense mechanism against viral infections. In mammals, passive immunity is provided by neutralizing antibodies passed to the offspring via the placenta or the milk as immunoglobulin G and secreted immunoglobulin A. With the long-term goal of producing virus-resistant livestock, we have generated mice carrying transgenes that encode the light and heavy chains of an antibody that is able to neutralize the neurotropic JHM strain of murine hepatitis virus (MHV-JHM). MHV-JHM causes acute encephalitis and acute and chronic demyelination in susceptible strains of mice and rats. Transgene expression was targeted to the lactating mammary gland by using the ovine β-lactoglobulin promoter. Milk from these transgenic mice contained up to 0.7 mg of recombinant antibody/ml. In vitro analysis of milk derived from different transgenic lines revealed a linear correlation between antibody expression and virus-neutralizing activity, indicating that the recombinant antibody is the major determinant of MHV-JHM neutralization in murine milk. Offspring of transgenic and control mice were challenged with a lethal dose of MHV-JHM. Litters suckling nontransgenic dams succumbed to fatal encephalitis, whereas litters suckling transgenic dams were fully protected against challenge, irrespective of whether they were transgenic. This demonstrates that a single neutralizing antibody expressed in the milk of transgenic mice is sufficient to completely protect suckling offspring against MHV-JHM-induced encephalitis. PMID:11222704

  8. Genetic mapping of quantitative trait loci affecting susceptibility to Marek's disease virus induced tumors in F2 intercross chickens.

    PubMed Central

    Vallejo, R L; Bacon, L D; Liu, H C; Witter, R L; Groenen, M A; Hillel, J; Cheng, H H

    1998-01-01

    Marek's disease (MD) is a lymphoproliferative disease caused by the MD virus (MDV), which costs the poultry industry nearly $1 billion annually. To identify quantitative trait loci (QTL) affecting MD susceptibility, the inbred lines 6(3) (MD resistant) and 7(2) (MD susceptible) were mated to create more than 300 F2 chickens. The F2 chickens were challenged with MDV JM strain, moderately virulent) at 1 wk of age and assessed for MD susceptibility. The QTL analysis was divided into three stages. In stage 1, 65 DNA markers selected from the chicken genetic maps were typed on the 40 most MD-susceptible and the 40 most MD-resistant F2 chickens, and 21 markers residing near suggestive QTL were revealed by analysis of variance (ANOVA). In stage 2, the suggestive markers plus available flanking markers were typed on 272 F2 chickens, and three suggestive QTL were identified by ANOVA. In stage 3, using the interval mapping program Map Manager and permutation tests, two significant and two suggestive MD QTL were identified on four chromosomal subregions. Three to five loci collected explained between 11 and 23% of the phenotypic MD variation, or 32-68% of the genetic variance. This study constitutes the first report in the domestic chicken on the mapping of non-major histocompatibility complex QTL affecting MD susceptibility. PMID:9475745

  9. Pulmonary infection with influenza A virus induces site-specific germinal center and T follicular helper cell responses.

    PubMed

    Boyden, Alexander W; Legge, Kevin L; Waldschmidt, Thomas J

    2012-01-01

    Protection from influenza A virus (IAV) challenge requires switched, high affinity Abs derived from long-lived memory B cells and plasma cells. These B cell subsets are generated in germinal centers (GCs), hallmark structures of T helper cell-driven B cell immunity. A full understanding of the GC reaction after respiratory IAV infection is lacking, as is the characterization of T follicular helper (T(FH)) cells that support GCs. Here, GC B cell and T(FH) cell responses were studied in mice following pulmonary challenge with IAV. Marked GC reactions were induced in draining lymph nodes (dLNs), lung, spleen and nasal-associated lymphoid tissue (NALT), although the magnitude and kinetics of the response was site-specific. Examination of switching within GCs demonstrated IgG2(+) cells to compose the largest fraction in dLNs, lung and spleen. IgA(+) GC B cells were infrequent in these sites, but composed a significant subset of the switched GC population in NALT. Further experiments demonstrated splenectomized mice to withstand a lethal recall challenge, suggesting the spleen to be unnecessary for long-term protection in spite of strong GC responses in this organ. Final studies showed that T(FH) cell numbers were highest in dLNs and spleen, and peaked in all sites prior to the height of the GC reaction. T(FH) cells purified from dLNs generated IL-21 and IFNγ upon activation, although CD4(+)CXCR5(-) T effector cells produced higher levels of all cytokines. Collectively, these findings reveal respiratory IAV infection to induce strong T helper cell-driven B cell responses in various organs, with each site displaying unique attributes. PMID:22792401

  10. Porcine reproductive and respiratory syndrome virus-induced immunosuppression exacerbates the inflammatory response to porcine respiratory coronavirus in pigs.

    PubMed

    Renukaradhya, Gourapura J; Alekseev, Konstantin; Jung, Kwonil; Fang, Ying; Saif, Linda J

    2010-10-01

    We performed a comprehensive analysis of innate and adaptive immune responses in dual-virus infected pigs to understand whether a pre-existing immunomodulatory respiratory viral infection affects the overall immunity to a subsequent porcine respiratory coronavirus (PRCV) infection in pigs. Pigs were either mock-infected or infected with porcine reproductive and respiratory syndrome virus (PRRSV), a virus known to cause immunosuppressive respiratory disease, and then pigs were co-infected with PRCV, which normally causes subclinical respiratory infection. We collected samples for six independent experiments from 178 pigs that were also used for pathological studies. We detected a significant reduction in innate NK-cell-mediated cytotoxic function in PRRSV-infected pigs, which was synergistically further decreased in pigs co-infected with PRCV. Subsequently, in association with clinical signs we observed elevated levels of proinflammatory (IL-6), Th-1 (IL-12), and regulatory (IL-10 and TGF-β) cytokines. Increased frequencies of CD4CD8 double-positive T lymphocytes and myeloid cells, in addition to the elevated Th-1 and proinflammatory cytokines in dual-infected pigs, contributed to the severity of lung disease in pigs. The results of our study clarify how each virus modulates the host innate and adaptive immune responses, leading to inflammatory reactions and lung pathology. Thus measurements of cytokines and frequencies of immune cells may serve as indicators of the progression of respiratory viral co-infections, and provide more definitive approaches for treatment. PMID:20883160

  11. In Vitro Infection with Dengue Virus Induces Changes in the Structure and Function of the Mouse Brain Endothelium

    PubMed Central

    Castellanos, Jaime E.

    2016-01-01

    Background The neurological manifestations of dengue disease are occurring with greater frequency, and currently, no information is available regarding the reasons for this phenomenon. Some viruses infect and/or alter the function of endothelial organs, which results in changes in cellular function, including permeability of the blood-brain barrier (BBB), which allows the entry of infected cells or free viral particles into the nervous system. Methods In the present study, we standardized two in vitro models, a polarized monolayer of mouse brain endothelial cells (MBECs) and an organized co-culture containing MBECs and astrocytes. Using these cell models, we assessed whether DENV-4 or the neuro-adapted dengue virus (D4MB-6) variant infects cells or induces changes in the structure or function of the endothelial barrier. Results The results showed that MBECs, but not astrocytes, were susceptible to infection with both viruses, although the percentage of infected cells was higher when the neuro-adapted virus variant was used. In both culture systems, DENV infection changed the localization of the tight junction proteins Zonula occludens (ZO-1) and Claudin-1 (Cln1), and this process was associated with a decrease in transendothelial resistance, an increase in macromolecule permeability and an increase in the paracellular passing of free virus particles. MBEC infection led to transcriptional up-regulation of adhesion molecules (VCAM-1 and PECAM) and immune mediators (MCP-1 and TNF- α) that are associated with immune cell transmigration, mainly in D4MB-6-infected cells. Conclusion These results indicate that DENV infection in MBECs altered the structure and function of the BBB and activated the endothelium, affecting its transcellular and paracellular permeability and favoring the passage of viruses and the transmigration of immune cells. This phenomenon can be harnessed for neurotropic and neurovirulent strains to infect and induce alterations in the CNS. PMID:27336851

  12. Conformational changes in Sindbis virus induced by decreased pH revealed by small-angle neutron scattering

    SciTech Connect

    Hernandez, Raquel; He, Lilin; Piper, Amanda; Meilleur, Flora; Brown, Dennis; Heller, William T

    2012-01-01

    Alphaviruses, such as Sindbis virus, undergo dramatic changes in three-dimensional structure upon exposure to low pH, and such exposure can establish conditions allowing fusion of the virus membrane with a cell plasma membrane upon return to neutral pH. While exposure to low pH is not required for entry of Sindbis virus into vertebrate or invertebrate cells, the conformational changes occurring at low pH may mimic those occurring upon virus-receptor interaction. Here, we employed small-angle neutron scattering with contrast variation to probe how the structure of a mammalian-grown Sindbis virus responds to moderately acidic pH. Several changes took place throughout the virion structure when the pH decreased from 7.2 to 6.4. Specifically, the RNA in the virion core underwent a conformational change. Additionally, the protein was redistributed. A significant amount of protein moved from the layer containing the lipid bilayer to the exterior of the virion. The results improve our understanding of the pH-driven alteration of Sindbis virus structure.

  13. Two and three dimensional characterization of Zucchini Yellow Mosaic Virus induced structural alterations in Cucurbita pepo L. plants.

    PubMed

    Zellnig, Günther; Pöckl, Michael Herbert; Möstl, Stefan; Zechmann, Bernd

    2014-05-01

    Infection of plants by Zucchini Yellow Mosaic Virus (ZYMV) induces severe ultrastructural changes. The aim of this study was to investigate ultrastructural changes during ZYMV-infection in Cucurbita pepo L. plants on the two and three dimensional (2D and 3D) level and to correlate these changes with the spread of ZYMV throughout the plant by transmission electron microscopy (TEM) and image analysis. This study revealed that after inoculation of the cotyledons ZYMV moved into roots [3 days post inoculation (dpi)], then moved upwards into the stem and apical meristem (5 dpi), then into the first true leaf (7 dpi) and could finally be found in all plant parts (9 dpi). ZYMV-infected cells contained viral inclusion bodies in the form of cylindrical inclusions (CIs). These CIs occurred in four different forms throughout the cytosol of roots and leaves: scrolls and pinwheels when cut transversely and long tubular structures and bundles of filaments when cut longitudinally. 3D reconstruction of ZYMV-infected cells containing scrolls revealed that they form long tubes throughout the cytosol. The majority has a preferred orientation and an average length and width of 3 μm and 120 nm, respectively. Image analysis revealed an increased size of cells and vacuoles (107% and 447%, respectively) in younger ZYMV-infected leaves leading to a similar ratio of cytoplasm to vacuole (about 1:1) in older and younger ZYMV-infected leaves which indicates advanced cell growth in younger tissues. The collected data advances the current knowledge about ZYMV-induced ultrastructural changes in Cucurbita pepo. PMID:24631670

  14. Nuclear receptor REV-ERBα mediates circadian sensitivity to mortality in murine vesicular stomatitis virus-induced encephalitis.

    PubMed

    Gagnidze, Khatuna; Hajdarovic, Kaitlyn H; Moskalenko, Marina; Karatsoreos, Ilia N; McEwen, Bruce S; Bulloch, Karen

    2016-05-17

    Certain components and functions of the immune system, most notably cytokine production and immune cell migration, are under circadian regulation. Such regulation suggests that circadian rhythms may have an effect on disease onset, progression, and resolution. In the vesicular stomatitis virus (VSV)-induced encephalitis model, the replication, caudal penetration, and survivability of intranasally applied VSV depends on both innate and adaptive immune mechanisms. In the current study, we investigated the effect of circadian time of infection on the progression and outcome of VSV-induced encephalitis and demonstrated a significant decrease in the survival rate in mice infected at the start of the rest cycle, zeitgeber time 0 (ZT0). The lower survival rate in these mice was associated with higher levels of circulating chemokine (C-C motif) ligand 2 (CCL2), a greater number of peripherally derived immune cells accumulating in the olfactory bulb (OB), and increased production of proinflammatory cytokines, indicating an immune-mediated pathology. We also found that the acrophase of molecular circadian clock component REV-ERBα mRNA expression in the OB coincides with the start of the active cycle, ZT12, when VSV infection results in a more favorable outcome. This result led us to hypothesize that REV-ERBα may mediate the circadian effect on survival following VSV infection. Blocking REV-ERBα activity before VSV administration resulted in a significant increase in the expression of CCL2 and decreased survival in mice infected at the start of the active cycle. These data demonstrate that REV-ERBα-mediated inhibition of CCL2 expression during viral-induced encephalitis may have a protective effect. PMID:27143721

  15. Immunotherapy of murine leukemia. Efficacy of passive serum therapy of Friend leukemia virus-induced disease in immunocompromised mice

    SciTech Connect

    Genovesi, E.V.; Livnat, D.; Collins, J.J.

    1983-02-01

    Previous studies have demonstrated that the passive therapy of Friend murine leukemia virus (F-MuLV)-induced disease with chimpanzee anti-F-MuLV serum is accompanied by the development of host antiviral humoral and cellular immunity, the latter measurable in adoptive transfer protocols and by the ability of serum-protected mice to resist virus rechallenge. The present study was designed to further examine the contribution of various compartments of the host immune system to serum therapy itself, as well as to the acquired antiviral immunity that develops in serum-protected mice, through the use of naturally immunocompromised animals (e.g., nude athymic mice and natural killer (NK)-deficient beige mutant mice) or mice treated with immunoabrogating agents such as sublethal irradiation, cyclophosphamide (Cytoxan (Cy)), cortisone, and /sup 89/Sr. The studies in nude mice indicate that while mature T-cells are not needed for effective serum therapy, they do appear to be necessary for the long-term resistance of serum-protected mice to virus rechallenge and for the generation of the cell population(s) responsible for adoptive transfer of antiviral immunity. Furthermore, this acquired resistance is not due to virus neutralization by serum antibodies since antibody-negative, Cy-treated, serum-protected mice still reject the secondary virus infection. Lastly, while the immunocompromise systems examined did effect various host antiviral immune responses, none of them, including the NK-deficient beige mutation, significantly diminished the efficacy of the passive serum therapy of F-MuLV-induced disease.

  16. Pathogenesis and molecular biology of progressive multifocal leukoencephalopathy, the JC virus-induced demyelinating disease of the human brain.

    PubMed Central

    Major, E O; Amemiya, K; Tornatore, C S; Houff, S A; Berger, J R

    1992-01-01

    Studies of the pathogenesis and molecular biology of JC virus infection over the last two decades have significantly changed our understanding of progressive multifocal leukoencephalopathy, which can be described as a subacute viral infection of neuroglial cells that probably follows reactivation of latent infection rather than being the consequence of prolonged JC virus replication in the brain. There is now sufficient evidence to suggest that JC virus latency occurs in kidney and B cells. However, JC virus isolates from brain or kidney differ in the regulatory regions of their viral genomes which are controlled by host cell factors for viral gene expression and replication. DNA sequences of noncoding regions of the viral genome display a certain heterogeneity among isolates from brain and kidney. These data suggest that an archetypal strain of JC virus exists whose sequence is altered during replication in different cell types. The JC virus regulatory region likely plays a significant role in establishing viral latency and must be acted upon for reactivation of the virus. A developing hypothesis is that reactivation takes place from latently infected B lymphocytes that are activated as a result of immune suppression. JC virus enters the brain in the activated B cell. Evidence for this mechanism is the detection of JC virus DNA in peripheral blood lymphocytes and infected B cells in the brains of patients with progressive multifocal leukoencephalopathy. Once virus enters the brain, astrocytes as well as oligodendrocytes support JC virus multiplication. Therefore, JC virus infection of neuroglial cells may impair other neuroglial functions besides the production and maintenance of myelin. Consequently our increased understanding of the pathogenesis of progressive multifocal leukoencephalopathy suggests new ways to intervene in JC virus infection with immunomodulation therapies. Perhaps along with trials of nucleoside analogs or interferon administration, this fatal disease, for which no consensus of antiviral therapy exists, may yield to innovative treatment protocols. Images PMID:1310438

  17. Immunity to Mexican H5N2 avian influenza viruses induced by a fowl pox-H5 recombinant.

    PubMed

    Webster, R G; Taylor, J; Pearson, J; Rivera, E; Paoletti, E

    1996-01-01

    The presence of highly pathogenic H5N2 avian influenza in domestic poultry in Mexico that is not being eradicated by conventional depopulation methods constitutes an imminent problem for poultry producers and agricultural authorities in the United States. The present report considers the candidate vaccines available to H5N2 influenza virus and establishes that a fowl pox-H5 recombinant can provide protection from lethal Mexican H5N2, and prevent shedding in the feces and transmission to contact birds. Inactivated and recombinant vaccines may be useful adjuncts to eradication if the H5N2 influenza virus spreads to the United States or the countries in Central America. PMID:8790900

  18. Chemoprevention of mammary tumor virus-induced and chemical carcinogen-induced rodent mammary tumors by natural plant products.

    PubMed

    Bhide, S V; Azuine, M A; Lahiri, M; Telang, N T

    1994-01-01

    The natural plant products turmeric, beta-carotene, catechin, and betel leaf extract were evaluated for their antitumor effects on mammary tumorigenesis in murine mammary tumor expressing C3H (Jax) mice and in Wistar rats treated with the chemical carcinogen 7-12-dimethylbenz(a)anthracene (DMBA). Administration of turmeric through the diet and of beta-carotene, catechin, and betel leaf extract through the drinking water to virgin female C3H mice resulted in decreased tumor incidence and tumor burden. Administering 5% turmeric in the diet from 2 months of age showed suppression of mammary tumor virus-related reverse transcriptase activity and of preneoplastic changes in the mammary glands. Furthermore, feeding turmeric from 6 months of age resulted in a 100% inhibition of mammary tumors. In the DMBA model of rat mammary tumorigenesis, administration of turmeric, catechin, and betel leaf extract resulted in decreased tumor burden and tumor incidence, and a delay in the onset of mammary tumors. PMID:7526904

  19. Latent Membrane Protein 1 of Epstein-Barr Virus Induces CD83 by the NF-κB Signaling Pathway

    PubMed Central

    Dudziak, Diana; Kieser, Arnd; Dirmeier, Ulrike; Nimmerjahn, Falk; Berchtold, Susanne; Steinkasserer, Alexander; Marschall, Gabriele; Hammerschmidt, Wolfgang; Laux, Gerhard; Bornkamm, Georg W.

    2003-01-01

    Epstein-Barr virus (EBV) infects human resting B cells and transforms them in vitro into continuously growing lymphoblastoid cell lines (LCLs). EBV nuclear antigen 2 (EBNA2) is one of the first viral proteins expressed after infection. It is able to transactivate viral as well as cellular target genes by interaction with cellular transcription factors. EBNA2 target genes can be studied easily by using an LCL (ER/EB2-5) in which wild-type EBNA2 is replaced by an estrogen-inducible EBNA2. Since the cell surface molecule CD83, a member of the immunoglobulin superfamily and a marker for mature dendritic cells, appeared on the surface of ER/EB2-5 cells within 3 h after the addition of estrogen, we analyzed the regulation of CD83 induction by EBV in more detail. Despite its rapid induction, CD83 turned out to be an indirect target gene of EBNA2. We could show that the viral latent membrane protein 1 (LMP1) is responsible for the induction of CD83 by using an LCL expressing a ligand- or antibody-inducible recombinant nerve growth factor receptor-LMP1 fusion protein. The inducibility of the CD83 promoter by LMP1 was mediated by the activation of NF-κB, as seen by use of luciferase reporter assays using the CD83 promoter and LMP1 mutants. Additionally, fusion constructs of the transmembrane domain of LMP1 and the intracellular signaling domain of CD40, TNF-R1, and TNF-R2 likewise transactivated the CD83 promoter via NF-κB. Our studies show that CD83 is also a target of the NF-κB signaling pathway in B cells. PMID:12857898

  20. Latent membrane protein 1 of Epstein-Barr virus induces CD83 by the NF-kappaB signaling pathway.

    PubMed

    Dudziak, Diana; Kieser, Arnd; Dirmeier, Ulrike; Nimmerjahn, Falk; Berchtold, Susanne; Steinkasserer, Alexander; Marschall, Gabriele; Hammerschmidt, Wolfgang; Laux, Gerhard; Bornkamm, Georg W

    2003-08-01

    Epstein-Barr virus (EBV) infects human resting B cells and transforms them in vitro into continuously growing lymphoblastoid cell lines (LCLs). EBV nuclear antigen 2 (EBNA2) is one of the first viral proteins expressed after infection. It is able to transactivate viral as well as cellular target genes by interaction with cellular transcription factors. EBNA2 target genes can be studied easily by using an LCL (ER/EB2-5) in which wild-type EBNA2 is replaced by an estrogen-inducible EBNA2. Since the cell surface molecule CD83, a member of the immunoglobulin superfamily and a marker for mature dendritic cells, appeared on the surface of ER/EB2-5 cells within 3 h after the addition of estrogen, we analyzed the regulation of CD83 induction by EBV in more detail. Despite its rapid induction, CD83 turned out to be an indirect target gene of EBNA2. We could show that the viral latent membrane protein 1 (LMP1) is responsible for the induction of CD83 by using an LCL expressing a ligand- or antibody-inducible recombinant nerve growth factor receptor-LMP1 fusion protein. The inducibility of the CD83 promoter by LMP1 was mediated by the activation of NF-kappaB, as seen by use of luciferase reporter assays using the CD83 promoter and LMP1 mutants. Additionally, fusion constructs of the transmembrane domain of LMP1 and the intracellular signaling domain of CD40, TNF-R1, and TNF-R2 likewise transactivated the CD83 promoter via NF-kappaB. Our studies show that CD83 is also a target of the NF-kappaB signaling pathway in B cells. PMID:12857898

  1. Inducible viral inoculation system with cultured plant cells facilitates a biochemical approach for virus-induced RNA silencing.

    PubMed

    Tamai, Atsushi; Dohi, Koji; Mori, Masasi; Meshi, Tetsuo; Ishikawa, Masayuki

    2010-03-01

    An inducible virus infection system was demonstrated to be an efficient protein expression system for inducing synchronous virus vector multiplication in suspension-cultured plant cells. A GFP-tagged tomato mosaic virus (ToMV-GFP) derivative that has a defect in its 130 K protein, a silencing suppressor of ToMV, was synchronously infected to tobacco BY2 cultured cells using this system. In the infection-induced cells, viral RNA was degraded rapidly, and a cytosol extract prepared from the infected cells showed RNA degradation activity specific for ToMV- or GFP-related sequences. In lysate prepared from cells infected by ToMV-GFP carrying the wild-type 130 K protein, sequence-specific RNA degradation activity was suppressed, although siRNA derived from the virus was generated. Furthermore, the 130 K protein interfered with 3'-end methylation of siRNA. The inducible virus infection system may provide a method for biochemical analysis of antiviral RNA silencing and silencing suppression by ToMV. PMID:20035436

  2. The three subtypes of tick-borne encephalitis virus induce encephalitis in a natural host, the bank vole (Myodes glareolus).

    PubMed

    Tonteri, Elina; Kipar, Anja; Voutilainen, Liina; Vene, Sirkka; Vaheri, Antti; Vapalahti, Olli; Lundkvist, Åke

    2013-01-01

    Tick-borne encephalitis virus (TBEV) infects bank voles (Myodes glareolus) in nature, but the relevance of rodents for TBEV transmission and maintenance is unclear. We infected colonized bank voles subcutaneously to study and compare the infection kinetics, acute infection, and potential viral persistence of the three known TBEV subtypes: European (TBEV-Eur), Siberian (TBEV-Sib) and Far Eastern (TBEV-FE). All strains representing the three subtypes were infective and highly neurotropic. They induced (meningo)encephalitis in some of the animals, however most of the cases did not present with apparent clinical symptoms. TBEV-RNA was cleared significantly slower from the brain as compared to other organs studied. Supporting our earlier findings in natural rodent populations, TBEV-RNA could be detected in the brain for up to 168 days post infection, but we could not demonstrate infectivity by cell culture isolation. Throughout all time points post infection, RNA of the TBEV-FE was detected significantly more often than RNA of the other two strains in all organs studied. TBEV-FE also induced prolonged viremia, indicating distinctive kinetics in rodents in comparison to the other two subtypes. This study shows that bank voles can develop a neuroinvasive TBEV infection with persistence of viral RNA in brain, and mount an anti-TBEV IgG response. The findings also provide further evidence that bank voles can serve as sentinels for TBEV endemicity. PMID:24349041

  3. The Three Subtypes of Tick-Borne Encephalitis Virus Induce Encephalitis in a Natural Host, the Bank Vole (Myodes glareolus)

    PubMed Central

    Tonteri, Elina; Kipar, Anja; Voutilainen, Liina; Vene, Sirkka; Vaheri, Antti; Vapalahti, Olli; Lundkvist, Åke

    2013-01-01

    Tick-borne encephalitis virus (TBEV) infects bank voles (Myodes glareolus) in nature, but the relevance of rodents for TBEV transmission and maintenance is unclear. We infected colonized bank voles subcutaneously to study and compare the infection kinetics, acute infection, and potential viral persistence of the three known TBEV subtypes: European (TBEV-Eur), Siberian (TBEV-Sib) and Far Eastern (TBEV-FE). All strains representing the three subtypes were infective and highly neurotropic. They induced (meningo)encephalitis in some of the animals, however most of the cases did not present with apparent clinical symptoms. TBEV-RNA was cleared significantly slower from the brain as compared to other organs studied. Supporting our earlier findings in natural rodent populations, TBEV-RNA could be detected in the brain for up to 168 days post infection, but we could not demonstrate infectivity by cell culture isolation. Throughout all time points post infection, RNA of the TBEV-FE was detected significantly more often than RNA of the other two strains in all organs studied. TBEV-FE also induced prolonged viremia, indicating distinctive kinetics in rodents in comparison to the other two subtypes. This study shows that bank voles can develop a neuroinvasive TBEV infection with persistence of viral RNA in brain, and mount an anti-TBEV IgG response. The findings also provide further evidence that bank voles can serve as sentinels for TBEV endemicity. PMID:24349041

  4. Borna disease virus-induced neuronal degeneration dependent on host genetic background and prevented by soluble factors

    PubMed Central

    Wu, Yuan-Ju; Schulz, Herbert; Lin, Chia-Ching; Saar, Kathrin; Patone, Giannino; Fischer, Heike; Hübner, Norbert; Heimrich, Bernd; Schwemmle, Martin

    2013-01-01

    Infection of newborn rats with Borne disease virus (BDV) results in selective degeneration of granule cell neurons of the dentate gyrus (DG). To study cellular countermechanisms that might prevent this pathology, we screened for rat strains resistant to this BDV-induced neuronal degeneration. To this end, we infected hippocampal slice cultures of different rat strains with BDV and analyzed for the preservation of the DG. Whereas infected cultures of five rat strains, including Lewis (LEW) rats, exhibited a disrupted DG cytoarchitecture, slices of three other rat strains, including Sprague–Dawley (SD), were unaffected. However, efficiency of viral replication was comparable in susceptible and resistant cultures. Moreover, these rat strain–dependent differences in vulnerability were replicated in vivo in neonatally infected LEW and SD rats. Intriguingly, conditioned media from uninfected cultures of both LEW and SD rats could prevent BDV-induced DG damage in infected LEW hippocampal cultures, whereas infection with BDV suppressed the availability of these factors from LEW but not in SD hippocampal cultures. To gain further insights into the genetic basis for this rat strain–dependent susceptibility, we analyzed DG granule cell survival in BDV-infected cultures of hippocampal neurons derived from the F1 and F2 offspring of the crossing of SD and LEW rats. Genome-wide association analysis revealed one resistance locus on chromosome (chr) 6q16 in SD rats and, surprisingly, a locus on chr3q21-23 that was associated with susceptibility. Thus, BDV-induced neuronal degeneration is dependent on the host genetic background and is prevented by soluble protective factors in the disease-resistant SD rat strain. PMID:23319640

  5. In ovo delivery of CpG DNA reduces avian infectious laryngotracheitis virus induced mortality and morbidity.

    PubMed

    Thapa, Simrika; Cader, Mohamed Sarjoon Abdul; Murugananthan, Kalamathy; Nagy, Eva; Sharif, Shayan; Czub, Markus; Abdul-Careem, Mohamed Faizal

    2015-04-01

    Endosomal toll-like receptor-21 and -9 sense CpG DNA activating production of pro-inflammatory mediators with antimicrobial effects. Here, we investigated the induction of antiviral response of in ovo delivered CpG DNA against infectious laryngotracheitis virus (ILTV) infection. We found that in ovo delivered CpG DNA significantly reduces ILTV infection pre-hatch correlating with the expression of IL-1β and increase of macrophages in lungs. As assessed in vitro, CpG DNA stimulated avian macrophages could be a potential source of IL-1β and other pro-inflammatory mediators. Since we also found that in ovo CpG DNA delivery maintains increased macrophages in the lungs post-hatch, we infected the chickens on the day of hatch with ILTV. We found that in ovo delivered CpG DNA significantly reduces mortality and morbidity resulting from ILTV infection encountered post-hatch. Thus, CpG DNA can be a candidate innate immune stimulant worthy of further investigation for the control of ILTV infection in chickens. PMID:25856635

  6. Virus-induced gene silencing reveals signal transduction components required for the Pvr9-mediated hypersensitive response in Nicotiana benthamiana.

    PubMed

    Tran, Phu-Tri; Choi, Hoseong; Choi, Doil; Kim, Kook-Hyung

    2016-08-01

    Resistance to pathogens mediated by plant resistance (R) proteins requires different signaling transduction components and pathways. Our previous studies revealed that a potyvirus resistance gene in pepper, Pvr9, confers a hypersensitive response (HR) to pepper mottle virus in Nicotiana benthamiana. Our results show that the Pvr9-mediated HR against pepper mottle virus infection requires HSP90, SGT1, NDR1, but not EDS1. These results suggest that the Pvr9-mediated HR is possibly related to the SA pathway but not the ET, JA, ROS or NO pathways. PMID:27236305

  7. Virus-Induced Alterations in Primary Metabolism Modulate Susceptibility to Tobacco rattle virus in Arabidopsis1[C][W

    PubMed Central

    Fernández-Calvino, Lourdes; Osorio, Sonia; Hernández, M. Luisa; Hamada, Ignacio B.; del Toro, Francisco J.; Donaire, Livia; Yu, Agnés; Bustos, Regla; Fernie, Alisdair R.; Martínez-Rivas, José M.; Llave, César

    2014-01-01

    During compatible virus infections, plants respond by reprogramming gene expression and metabolite content. While gene expression studies are profuse, our knowledge of the metabolic changes that occur in the presence of the virus is limited. Here, we combine gene expression and metabolite profiling in Arabidopsis (Arabidopsis thaliana) infected with Tobacco rattle virus (TRV) in order to investigate the influence of primary metabolism on virus infection. Our results revealed that primary metabolism is reconfigured in many ways during TRV infection, as reflected by significant changes in the levels of sugars and amino acids. Multivariate data analysis revealed that these alterations were particularly conspicuous at the time points of maximal accumulation of TRV, although infection time was the dominant source of variance during the process. Furthermore, TRV caused changes in lipid and fatty acid composition in infected leaves. We found that several Arabidopsis mutants deficient in branched-chain amino acid catabolism or fatty acid metabolism possessed altered susceptibility to TRV. Finally, we showed that increments in the putrescine content in TRV-infected plants correlated with enhanced tolerance to freezing stress in TRV-infected plants and that impairment of putrescine biosynthesis promoted virus multiplication. Our results thus provide an interesting overview for a better understanding of the relationship between primary metabolism and virus infection. PMID:25358898

  8. Histopathology and immunohistochemistry of canine distemper virus-induced footpad hyperkeratosis (hard Pad disease) in dogs with natural canine distemper.

    PubMed

    Koutinas, A F; Baumgärtner, W; Tontis, D; Polizopoulou, Z; Saridomichelakis, M N; Lekkas, S

    2004-01-01

    Hard pad disease represents an uncommon manifestation of canine distemper virus (CDV) infection with a still uncertain pathogenesis. To study the pathogenesis of this uncommon, virally induced cutaneous lesion, the footpads of 19 dogs with naturally occurring distemper were investigated for histologic changes and distribution pattern of CDV antigen. All dogs displayed clinical signs of distemper, which had lasted from 10 to 75 days. Overt digital hyperkeratosis was observed in 12 animals (group A), whereas the footpads of the remaining seven dogs appeared normal macroscopically (group B). Orthokeratotic hyperkeratosis (12/12; 100%), irregular acanthosis (11/12; 92%), thickened rete ridges (10/12; 83%), and mild mononuclear perivascular (10/ 12; 83%) and periadnexal (7/12; 58%) dermatitis were the most common findings in dogs with hard pad disease. Surprisingly, orthokeratotic hyperkeratosis (5/7; 71%), irregular acanthosis (5/7; 71%), and thickened rete ridges (4/7; 57%) were also seen in the dogs without clinical evidence of digital hyperkeratosis. CDV-specific inclusion bodies and ballooning degeneration were not observed in the footpad epidermis of the 19 dogs. Immunohis-tochemistry revealed that CDV antigen was most frequently found in the stratum spinosum and granulosum and in the epithelial cells of the eccrine sweat glands and only rarely in the basal layer. Fibroblasts, pericytes, endothelial cells, and hair follicles were also positive in some animals. Despite the obvious difference regarding the macroscopic picture, the microscopic changes were less prominent between the animal groups. The selective infection of keratinocytes in the stratum spinosum might be the key event for the development of hard pad disease in the dog. PMID:14715962

  9. Mir-302c mediates influenza A virus-induced IFNβ expression by targeting NF-κB inducing kinase.

    PubMed

    Gui, Shulin; Chen, Xueyuan; Zhang, Mo; Zhao, Fanpeng; Wan, Yushun; Wang, Li; Xu, Gang; Zhou, Li; Yue, Xin; Zhu, Ying; Liu, Shi

    2015-12-21

    Little is known about the role of microRNA during influenza A virus (IAV) infection. We observed that NIK 3'UTR luciferase activity was elevated during IAV infection. Further studies demonstrated that miR-302c reduced NIK expression, resulting in the reduction of IFNβ mRNA expression. We found that miR-302c prevented the translocation of NF-κB from the cytosol to the nucleus. Furthermore, IAV infection downregulated miR-302c expression, leading to the activation of IFNβ expression and the inhibition of viral replication. Compared to miR-302c, miR-520e cannot promote viral replication and production, although the two microRNAs target the same site of the NIK 3'UTR. Collectively, our work defines a novel signaling pathway implicated in the control of IFNβ mRNA expression during IAV infection. PMID:26602079

  10. The influence of CD4 and CXCR4 on maedi-visna virus-induced syncytium formation.

    PubMed

    Hovden, Arnt-Ove; Sommerfelt, Maja A

    2002-10-01

    CD4 is the principal binding site for human and simian immunodeficiency virus (HIV/SIV) receptor interactions and the a chemokine receptor CXCR4 has been implicated as a primordial lentivirus receptor. This study sought to determine the relevance of CD4 and CXCR4 in virus-receptor interactions for the prototype lentivirus, maedi-visna virus (MVV) of sheep. Neither CD4 nor alpha/beta chemokine receptors represent principal receptors for MVV since human osteosarcoma cells devoid of these molecules were susceptible to productive infection. Interestingly, the presence of either CD4 and/or CXCR4 on indicator cells dramatically enhanced MVV-induced cell fusion (syncytium formation) for three independent virus strains. Syncytium formation results from virus-receptor interactions and can be inhibited by receptor ligands. However, neither SDF-la that binds CXCR4 nor recombinant gp120 (rgp120) that binds CD4 could specifically inhibit the observed enhancement of MVV-induced cell fusion under conditions that significantly reduced HIV-1-induced cell fusion. Our observations suggest that CD4 and CXCR4 may represent optional auxiliary components of an MVV receptor (or receptor complex) that facilitate MVV-mediated membrane fusion events, a feature important for virus entry. This potential accessory role for CXCR4 in MW receptor interactions may reflect the distant relationship between the ovine (MVV) and the human/feline lentiviruses (HIV/FIV). PMID:12583436

  11. Vaccination against H5 avian influenza virus induces long-term humoral immune responses in flamingoes (Phoenicopterus spp.).

    PubMed

    Fernández-Bellon, Hugo; Vergara-Alert, Júlia; Almagro, Vanessa; Rivas, Raquel; Sánchez, Azucena; Martínez, María Carmen; Majó, Natàlia; Busquets, Núria; Ramis, Antonio

    2016-06-01

    Avian influenza (AI) can represent a threat to endangered wild birds, as demonstrated with the H5N1 highly pathogenic AI (HPAI) outbreaks. Vaccination against AI using inactivated H5-vaccines has been shown to induce humoral immune response in zoo bird species. In this study, the long-term efficacy of H5-vaccination was evaluated in flamingoes from Barcelona Zoo. Specific H5-antibody titres were maintained at high levels (geometric mean titres ≥32) for over 7 years after vaccination, both against the H5N9 and H5N3 vaccine strains, as well as H5N3 and H5N1 reference strains. In addition the breadth of the immune response was also studied by testing antibody production against H1-, H3-, H4-, H7-, and H10-subtypes. It was observed that most flamingoes presented specific antibodies against H1 virus subtypes, but titres to the other HA-subtypes were rarely detected. We show that AI-vaccines can induce immunity lasting seven years in flamingoes, which suggests that vaccination can provide long term protection from HPAI outbreaks in zoo birds. PMID:27151883

  12. Hepatitis B virus induces hypoxia-inducible factor-2α expression through hepatitis B virus X protein.

    PubMed

    Hu, Jian-Li; Liu, Li-Ping; Yang, Sheng-Li; Fang, Xiefan; Wen, Lu; Ren, Quan-Guang; Yu, Chao

    2016-03-01

    A growing number of studies suggest that the hepatitis B virus X protein (HBx) enhances the protein stability of the hypoxia-inducible factor-1α (HIF-1α). However, the relationship between hepatitis B virus (HBV), HBx and hypoxia-inducible factor-2α (HIF-2α) has not yet been fully elucidated. Immunohistochemical analysis was employed to detect the expression of HIF-2α in normal liver, HBV-related chronic hepatitis, and HBV-related and non-HBV-related hepatocellular carcinoma (HCC) tissues. Quantitative real‑time PCR (qPCR) and western blotting were used to investigate the impact of HBV and HBx on the expression of HIF‑2α. Immunoprecipitation and immunofluorescence were applied to explore the underlying mechanisms. The HIF‑2α expression was found to be higher in HBV‑related chronic hepatitis tissues than in normal liver tissues. Furthermore, it was higher in HBV‑related HCC tissues and HBV‑integrated HepG2 cells than in the corresponding non‑HBV‑related HCC tissues and HepG2 cells. Both HBV and HBx enhanced the protein stability of HIF‑2α. HBx‑mediated upregulation of HIF‑2α resulted mainly from an inhibition of the degradation of HIF‑2α due to the binding of HBx to the von Hippel‑Lindau protein (pVHL). In addition, HBx upregulated the expression of HIF‑2α by activating the NF‑κB signaling pathway. Thus, the present study identified that HBV induces the HIF‑2α expression through its encoded protein HBx. This upregulates the HIF-2α expression by binding to the pVHL activating the NF-κB signaling pathway. PMID:26647960

  13. Infection of Murine Macrophages by Salmonella enterica Serovar Heidelberg Blocks Murine Norovirus Infectivity and Virus-induced Apoptosis.

    PubMed

    Agnihothram, Sudhakar S; Basco, Maria D S; Mullis, Lisa; Foley, Steven L; Hart, Mark E; Sung, Kidon; Azevedo, Marli P

    2015-01-01

    Gastroenteritis caused by bacterial and viral pathogens constitutes a major public health threat in the United States accounting for 35% of hospitalizations. In particular, Salmonella enterica and noroviruses cause the majority of gastroenteritis infections, with emergence of sporadic outbreaks and incidence of increased infections. Although mechanisms underlying infections by these pathogens have been individually studied, little is known about the mechanisms regulating co-infection by these pathogens. In this study, we utilized RAW 264.7 murine macrophage cells to investigate the mechanisms governing co-infection with S. enterica serovar Heidelberg and murine norovirus (MNV). We demonstrate that infection of RAW 264.7 cells with S. enterica reduces the replication of MNV, in part by blocking virus entry early in the virus life cycle, and inducing antiviral cytokines later in the infection cycle. In particular, bacterial infection prior to, or during MNV infection affected virus entry, whereas MNV entry remained unaltered when the virus infection preceded bacterial invasion. This block in virus entry resulted in reduced virus replication, with the highest impact on replication observed during conditions of co-infection. In contrast, bacterial replication showed a threefold increase in MNV-infected cells, despite the presence of antibiotic in the medium. Most importantly, we present evidence that the infection of MNV-infected macrophages by S. enterica blocked MNV-induced apoptosis, despite allowing efficient virus replication. This apoptosis blockade was evidenced by reduction in DNA fragmentation and absence of poly-ADP ribose polymerase (PARP), caspase 3 and caspase 9 cleavage events. Our study suggests a novel mechanism of pathogenesis whereby initial co-infection with these pathogens could result in prolonged infection by either of these pathogens or both together. PMID:26658916

  14. Dengue Virus-Induced Inflammation of the Endothelium and the Potential Roles of Sphingosine Kinase-1 and MicroRNAs

    PubMed Central

    Aloia, Amanda L.; Abraham, Alexander M.; Bonder, Claudine S.; Pitson, Stuart M.; Carr, Jillian M.

    2015-01-01

    One of the main pathogenic effects of severe dengue virus (DENV) infection is a vascular leak syndrome. There are no available antivirals or specific DENV treatments and without hospital support severe DENV infection can be life-threatening. The cause of the vascular leakage is permeability changes in the endothelial cells lining the vasculature that are brought about by elevated vasoactive cytokine and chemokines induced following DENV infection. The source of these altered cytokine and chemokines is traditionally believed to be from DENV-infected cells such as monocyte/macrophages and dendritic cells. Herein we discuss the evidence for the endothelium as an additional contributor to inflammatory and innate responses during DENV infection which may affect endothelial cell function, in particular the ability to maintain vascular integrity. Furthermore, we hypothesise roles for two factors, sphingosine kinase-1 and microRNAs (miRNAs), with a focus on several candidate miRNAs, which are known to control normal vascular function and inflammatory responses. Both of these factors may be potential therapeutic targets to regulate inflammation of the endothelium during DENV infection. PMID:26609198

  15. Hepatitis C Virus Induces Epidermal Growth Factor Receptor Activation via CD81 Binding for Viral Internalization and Entry

    PubMed Central

    Diao, Jingyu; Pantua, Homer; Ngu, Hai; Komuves, Laszlo; Diehl, Lauri; Schaefer, Gabriele

    2012-01-01

    While epidermal growth factor receptor (EGFR) has been shown to be important in the entry process for multiple viruses, including hepatitis C virus (HCV), the molecular mechanisms by which EGFR facilitates HCV entry are not well understood. Using the infectious cell culture HCV model (HCVcc), we demonstrate that the binding of HCVcc particles to human hepatocyte cells induces EGFR activation that is dependent on interactions between HCV and CD81 but not claudin 1. EGFR activation can also be induced by antibody mediated cross-linking of CD81. In addition, EGFR ligands that enhance the kinetics of HCV entry induce EGFR internalization and colocalization with CD81. While EGFR kinase inhibitors inhibit HCV infection primarily by preventing EGFR endocytosis, antibodies that block EGFR ligand binding or inhibitors of EGFR downstream signaling have no effect on HCV entry. These data demonstrate that EGFR internalization is critical for HCV entry and identify a hitherto-unknown association between CD81 and EGFR. PMID:22855500

  16. A highly conserved epitope-vaccine candidate against varicella-zoster virus induces neutralizing antibodies in mice.

    PubMed

    Zhu, Rui; Liu, Jian; Chen, Chunye; Ye, Xiangzhong; Xu, Longfa; Wang, Wei; Zhao, Qinjian; Zhu, Hua; Cheng, Tong; Xia, Ningshao

    2016-03-18

    Varicella-zoster virus (VZV) is a highly infectious agent of varicella and herpes zoster (HZ). Vaccination is by far the most effective way to prevent these diseases. More safe, stable and efficient vaccines, such as epitope-based vaccines, now have been increasingly investigated by many researchers. However, only a few VZV neutralizing epitopes have been identified to date. We have previously identified a linear epitope between amino acid residues 121 and 135 of gE. In this study, we validated that this epitope is highly conserved amongst different VZV strains that covered five existing phylogenetic clades with an identity of 100%. We evaluated the immunogenicity of the recombinant hepatitis B virus core (HBc) virus-like particles (VLPs) which included amino acids (121-135). VZV-gE-specific antibodies were detected in immunized mouse serum using ELISA. The anti-peptide antiserum positively detected VZV via Western blot and immunofluorescent staining assays. More importantly, these peptides could neutralize VZV, indicating that these peptides represented neutralizing epitopes. These findings have important implications for the development of epitope-based protective VZV vaccines. PMID:26873057

  17. Measles virus C protein suppresses gamma-activated factor formation and virus-induced cell growth arrest

    SciTech Connect

    Yokota, Shin-ichi; Okabayashi, Tamaki; Fujii, Nobuhiro

    2011-05-25

    Measles virus (MeV) produces two accessory proteins, V and C, from the P gene. These accessory proteins have been reported to contribute to efficient virus proliferation through the modulation of host cell events. Our previous paper described that Vero cell-adapted strains of MeV led host cells to growth arrest through the upregulation of interferon regulatory factor 1 (IRF-1), and wild strains did not. In the present study, we found that C protein expression levels varied among MeV strains in infected SiHa cells. C protein levels were inversely correlated with IRF-1 expression levels and with cell growth arrest. Forced expression of C protein released cells from growth arrest. C-deficient recombinant virus efficiently upregulated IRF-1 and caused growth arrest more efficiently than the wild-type virus. C protein preferentially bound to phosphorylated STAT1 and suppressed STAT1 dimer formation. We conclude that MeV C protein suppresses IFN-{gamma} signaling pathway via inhibition of phosphorylated STAT1 dimerization.

  18. Central Nervous System Stromal Cells Control Local CD8(+) T Cell Responses during Virus-Induced Neuroinflammation.

    PubMed

    Cupovic, Jovana; Onder, Lucas; Gil-Cruz, Cristina; Weiler, Elke; Caviezel-Firner, Sonja; Perez-Shibayama, Christian; Rülicke, Thomas; Bechmann, Ingo; Ludewig, Burkhard

    2016-03-15

    Stromal cells generate a complex cellular scaffold that provides specialized microenvironments for lymphocyte activation in secondary lymphoid organs. Here, we assessed whether local activation of stromal cells in the central nervous system (CNS) is mandatory to transfer immune recognition from secondary lymphoid organs into the infected tissue. We report that neurotropic virus infection in mice triggered the establishment of such stromal cell niches in the CNS. CNS stromal cell activation was dominated by a rapid and vigorous production of CC-motif chemokine receptor (CCR) 7 ligands CCL19 and CCL21 by vascular endothelial cells and adjacent fibroblastic reticular cell (FRC)-like cells in the perivascular space. Moreover, CCR7 ligands produced by CNS stromal cells were crucial to support recruitment and local re-activation of antiviral CD8(+) T cells and to protect the host from lethal neuroinflammatory disease, indicating that CNS stromal cells generate confined microenvironments that control protective T cell immunity. PMID:26921107

  19. The Hemagglutinin Stem-Binding Monoclonal Antibody VIS410 Controls Influenza Virus-Induced Acute Respiratory Distress Syndrome.

    PubMed

    Baranovich, Tatiana; Jones, Jeremy C; Russier, Marion; Vogel, Peter; Szretter, Kristy J; Sloan, Susan E; Seiler, Patrick; Trevejo, Jose M; Webby, Richard J; Govorkova, Elena A

    2016-04-01

    Most cases of severe influenza are associated with pulmonary complications, such as acute respiratory distress syndrome (ARDS), and no antiviral drugs of proven value for treating such complications are currently available. The use of monoclonal antibodies targeting the stem of the influenza virus surface hemagglutinin (HA) is a rapidly developing strategy for the control of viruses of multiple HA subtypes. However, the mechanisms of action of these antibodies are not fully understood, and their ability to mitigate severe complications of influenza has been poorly studied. We evaluated the effect of treatment with VIS410, a human monoclonal antibody targeting the HA stem region, on the development of ARDS in BALB/c mice after infection with influenza A(H7N9) viruses. Prophylactic administration of VIS410 resulted in the complete protection of mice against lethal A(H7N9) virus challenge. A single therapeutic dose of VIS410 given 24 h after virus inoculation resulted in dose-dependent protection of up to 100% of mice inoculated with neuraminidase inhibitor-susceptible or -resistant A(H7N9) viruses. Compared to the outcomes in mock-treated controls, a single administration of VIS410 improved viral clearance from the lungs, reduced virus spread in lungs in a dose-dependent manner, resulting in a lower lung injury score, reduced the extent of the alteration in lung vascular permeability and protein accumulation in bronchoalveolar lavage fluid, and improved lung physiologic function. Thus, antibodies targeting the HA stem can reduce the severity of ARDS and show promise as agents for controlling pulmonary complications in influenza. PMID:26787699

  20. Immunity to herpes simplex virus type 2. Suppression of virus-induced immune responses in ultraviolet B-irradiated mice

    SciTech Connect

    Yasumoto, S.; Hayashi, Y.; Aurelian, L.

    1987-10-15

    Ultraviolet B irradiation (280 to 320 nm) of mice at the site of intradermal infection with herpes simplex virus type 2 increased the severity of the herpes simplex virus type 2 disease and decreased delayed-type hypersensitivity (DTH) responses to viral antigen. Decrease in DTH resulted from the induction of suppressor T cells, as evidenced by the ability of spleen cells from UV-irradiated mice to inhibit DTH and proliferative responses after adoptive transfer. Lymph node cells from UV-irradiated animals did not transfer suppression. DTH was suppressed at the induction but not the expression phase. Suppressor T cells were Lyt-1+, L3T4+, and their activity was antigen-specific. However, after in vitro culture of spleen cells from UV-irradiated mice with herpes simplex virus type 2 antigen, suppressor activity was mediated by Lyt-2+ cells. Culture supernatants contained soluble nonantigen-specific suppressive factors.

  1. Neonatal testicular cell transplantation restores murine spermatogenesis damaged in the course of herpes simplex virus-induced orchitis.

    PubMed

    Malolina, Ekaterina A; Kulibin, Andrey Yu; Kushch, Alla A

    2016-04-01

    Genital tract infection and inflammation may affect male fertility, causing germ and Sertoli cell loss. We determined if testicular cell transplantation is effective at repairing testicular injury induced by herpes simplex virus (HSV) orchitis. ROSA26 mice were used as donors and the recipients were C57BL/6 mice after HSV testicular inoculation; some of the recipients were treated with the antiviral drug acyclovir (ACV). ACV reduced the amount of HSV antigen in testes on Day 3 after transplantation and enhanced the efficacy of transplantation at Day 30. In recipient testes, donor Sertoli cells formed new seminiferous tubules; significantly more new tubules were observed in the testes of ACV-treated mice compared with mice not treated with ACV (17.8% vs 3.6%). Over half (50.4%) of new tubules in ACV-treated testes contained germ cells and round spermatids were detected in 14.2% of new tubules compared with 15.9% and 5.3% in testes not treated with ACV, respectively. At Day 150 the seminiferous epithelium was completely recovered in some donor tubules and elongated spermatids were observed inside it. Thus, our findings reveal the effectiveness of the combination of antiviral therapy with neonatal testis-cell transplantation for the restoration of spermatogenesis damaged by viral infection. PMID:25399480

  2. Influenza Virus Induces Cholesterol-Enriched Endocytic Recycling Compartments for Budozone Formation via Cell Cycle-Independent Centrosome Maturation

    PubMed Central

    Harada, Yoshimi; Osari, Suguru; Nagata, Kyosuke

    2015-01-01

    Influenza virus particles are assembled at the plasma membrane in concert with incorporation of the virus genome, but the details of its spatio-temporal regulation are not understood. Here we showed that influenza virus infection induces the assembly of pericentrosomal endocytic recycling compartment (ERC) through the activation of Rab11a GTPase and cell cycle-independent maturation of centrosome by YB-1, a multifunctional protein that is involved in mitotic division, RNA metabolism and tumorigenesis. YB-1 is recruited to the centrosome in infected cells and is required for anchoring microtubules to the centrosome. We also found that viral infection accumulates cholesterol in ERC and is dependent on YB-1. Depletion of YB-1 shows reduced cholesterol-enriched ERC and prevented budozone formation at the plasma membrane. These results suggest that cholesterol in recycling endosomes, which are emanated from ERC, may trigger the virus assembly concomitantly with the packaging of the virus genome. We propose that the virus genome is transported to the plasma membrane by cholesterol-enriched recycling endosomes through cell cycle-independent activation of the centrosome by YB-1. PMID:26575487

  3. Organ-Specific Protective Role of NKT Cells in Virus-Induced Inflammatory Demyelination and Myocarditis Depends on Mouse Strain

    PubMed Central

    Kawai, Eiichiro; Sato, Fumitaka; Omura, Seiichi; Martinez, Nicholas E.; Reddy, Pratap C.; Taniguchi, Masaru; Tsunoda, Ikuo

    2014-01-01

    Theiler’s murine encephalomyelitis virus (TMEV) can induce demyelination or myocarditis in susceptible mouse strains. A deficiency of NKT cells exacerbated TMEV-induced demyelinating disease (TMEV-IDD) in SJL/J and BALB/c mice. In C57BL/6 background, however, NKT-cell-deficient Jαt 18 KO mice remained as resistant to TMEV-IDD as wild-type mice. Echocardiography and histology showed that Jα18 KO mice developed more severe myocarditis (greater T cell infiltration and fibrosis) than wild-type mice, suggesting a protective role of NKT cells in myocarditis in C57BL/6 mice. Jα18 KO mice had higher cardiac viral RNA and anti-viral antibody titers, but had lower lymphoproliferation and IL-4 and IL-10 production. PMID:25434008

  4. Roles of the PI3K/Akt pathway in Epstein-Barr virus-induced cancers and therapeutic implications.

    PubMed

    Chen, Jiezhong

    2012-12-12

    Viruses have been shown to be responsible for 10%-15% of cancer cases. Epstein-Barr virus (EBV) is the first virus to be associated with human malignancies. EBV can cause many cancers, including Burkett's lymphoma, Hodgkin's lymphoma, post-transplant lymphoproliferative disorders, nasopharyngeal carcinoma and gastric cancer. Evidence shows that phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) plays a key role in EBV-induced malignancies. The main EBV oncoproteins latent membrane proteins (LMP) 1 and LMP2A can activate the PI3K/Akt pathway, which, in turn, affects cell survival, apoptosis, proliferation and genomic instability via its downstream target proteins to cause cancer. It has also been demonstrated that the activation of the PI3K/Akt pathway can result in drug resistance to chemotherapy. Thus, the inhibition of this pathway can increase the therapeutic efficacy of EBV-associated cancers. For example, PI3K inhibitor Ly294002 has been shown to increase the effect of 5-fluorouracil in an EBV-associated gastric cancer cell line. At present, dual inhibitors of PI3K and its downstream target mammalian target of rapamycin have been used in clinical trials and may be included in treatment regimens for EBV-associated cancers. PMID:24175221

  5. Epstein-Barr virus induces cellular transcription factors to allow active expression of EBER genes by RNA polymerase III.

    PubMed

    Felton-Edkins, Zoë A; Kondrashov, Alexander; Karali, Dimitra; Fairley, Jennifer A; Dawson, Christopher W; Arrand, John R; Young, Lawrence S; White, Robert J

    2006-11-10

    The EBER genes of Epstein-Barr virus (EBV) are transcribed by RNA polymerase (pol) III to produce untranslated RNAs that are implicated in oncogenesis. These EBER transcripts are the most highly expressed viral gene products in EBV-transformed cells. We have identified changes to the cellular transcription machinery that may contribute to the high levels of EBER RNA. These include phosphorylation of ATF2, which interacts with EBER promoters. A second is induction of TFIIIC, a pol III-specific factor that activates EBER genes; all five subunits of TFIIIC are overexpressed in EBV-positive cells. In addition, EBV induces BDP1, a subunit of the pol III-specific factor TFIIIB. Although BDP1 is the only TFIIIB subunit induced by EBV, its induction is sufficient to stimulate EBER expression in vivo, implying a limiting function. The elevated levels of BDP1 and TFIIIC in EBV-positive cells stimulate production of tRNA, 7SL, and 5S rRNA. Abnormally high expression of these cellular pol III products may contribute to the ability of EBV to enhance growth potential. PMID:16956891

  6. Measles virus-induced immune suppression in the cotton rat (Sigmodon hispidus) model depends on viral glycoproteins.

    PubMed Central

    Niewiesk, S; Eisenhuth, I; Fooks, A; Clegg, J C; Schnorr, J J; Schneider-Schaulies, S; ter Meulen, V

    1997-01-01

    Immune suppression during measles accounts for most of the morbidity and mortality associated with the virus infection. Experimental study of this phenomenon has been hampered by the lack of a suitable animal model. We have used the cotton rat to demonstrate that mitogen-induced proliferation of spleen cells from measles virus-infected animals is impaired. Proliferation inhibition is seen in all lymphocyte subsets and is not dependent on viral replication. Cells which express the viral glycoproteins (hemagglutinin and fusion protein) transiently by transfection induce proliferation inhibition after intraperitoneal inoculation, whereas application of a recombinant measles virus in which measles virus glycoproteins are replaced with the vesicular stomatitis virus G protein does not have an antiproliferative effect. Therefore, in vivo expression of measles virus glycoproteins is sufficient and necessary to induce inhibition of lymphocyte proliferation. PMID:9311794

  7. Sirtuin 1 regulates dendritic cell activation and autophagy during Respiratory Syncytial Virus-induced immune responses1

    PubMed Central

    Owczarczyk, Anna B.; Schaller, Matthew A.; Reed, Michelle; Rasky, Andrew J.; Lombard, David B.; Lukacs, Nicholas W.

    2015-01-01

    Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infection in children worldwide. Sirtuin 1 (SIRT1), an NAD+ dependent deacetylase, has been associated with the induction of autophagy and the regulation of inflammatory mediators. We found that Sirt1 was upregulated in mouse lung after RSV infection. Infected animals that received EX-527, a selective SIRT1 inhibitor, displayed exacerbated lung pathology, with increased mucus production, elevated viral load, and enhanced Th2 cytokine production. Gene expression analysis of isolated cell populations revealed that Sirt1 was most highly upregulated in RSV-treated dendritic cells (DCs). Upon RSV infection, EX-527-treated DCs, Sirt1 siRNA-treated DCs, or DCs from conditional knockout (Sirt1f/f-CD11c–Cre+) mice showed downregulated inflammatory cytokine gene expression and attenuated autophagy. Finally, RSV infection of Sirt1f/f-CD11c–Cre+ mice resulted in altered lung and lymph node cytokine responses, leading to exacerbated pathology. These data indicate that SIRT1 promotes DC activation associated with autophagy-mediated processes during RSV infection, thereby directing efficient antiviral immune responses. PMID:26157176

  8. Role of hepatitis C virus induced osteopontin in epithelial to mesenchymal transition, migration and invasion of hepatocytes.

    PubMed

    Iqbal, Jawed; McRae, Steven; Mai, Thi; Banaudha, Krishna; Sarkar-Dutta, Mehuli; Waris, Gulam

    2014-01-01

    Osteopontin (OPN) is a secreted phosphoprotein which has been linked to tumor progression and metastasis in a variety of cancers including hepatocellular carcinoma (HCC). Previous studies have shown that OPN is upregulated during liver injury and inflammation. However, the role of OPN in hepatitis C virus (HCV)-induced liver disease pathogenesis is not known. In this study, we determined the induction of OPN, and then investigated the effect of secreted forms of OPN in epithelial to mesenchymal transition (EMT), migration and invasion of hepatocytes. We show the induction of OPN mRNA and protein expression by HCV-infection. Our results also demonstrate the processing of precursor OPN (75 kDa) into 55 kDa, 42 kDa and 36 kDa forms of OPN in HCV-infected cells. Furthermore, we show the binding of secreted OPN to integrin αVβ3 and CD44 at the cell surface, leading to the activation of downstream cellular kinases such as focal adhesion kinase (FAK), Src, and Akt. Importantly, our results show the reduced expression of epithelial marker (E-cadherin) and induction of mesenchymal marker (N-cadherin) in HCV-infected cells. We also show the migration and invasion of HCV-infected cells using wound healing assay and matrigel coated Boyden chamber. In addition, we demonstrate the activation of above EMT markers, and the critical players involved in OPN-mediated cell signaling cascade using primary human hepatocytes infected with Japanese fulminant hepatitis (JFH)-1 HCV. Taken together, these studies suggest a potential role of OPN in inducing chronic liver disease and HCC associated with chronic HCV infection. PMID:24498111

  9. Evidence for possible role of toll-like receptor 3 mediating virus-induced progression of pituitary adenomas.

    PubMed

    Zheng, Xin; Li, Song; Zang, Zhenle; Hu, Jintao; An, Jiayin; Pei, Xiangdong; Zhu, Feng; Zhang, Weihua; Yang, Hui

    2016-05-01

    Tumor-related viruses are known to be involved in initiation and progression of certain tumors. However, the relationship between virus and pituitary adenomas (PAs) remains unknown. Here, we investigated infection status of three types of viruses (HPV16, HHV6B and HSV1) and expression level of toll-like receptor 3 (TLR3) in 60 human PA samples. We also determined the role of TLR3 signaling pathway on a PA cell line (GH3). We firstly found that positive rates of HPV16 and HHV6B infection were significantly higher in invasive PA samples than in noninvasive samples (P < 0.01). Similarly, TLR3 mRNA and protein expression also increased in invasive PA samples (P < 0.01). In vitro analysis indicated that GH3 cell proliferation and survival were enhanced by TLR3 activation, which was accompanied by NF-κB activation. Our data indicate that HPV16 and HHV6B viruses may be involved in promoting the progression of PA by activating the TLR3 signaling pathway. PMID:26891958

  10. P-glycoprotein activity in the blood-brain barrier is affected by virus-induced neuroinflammation and antipsychotic treatment.

    PubMed

    Doorduin, Janine; de Vries, Erik F J; Dierckx, Rudi A; Klein, Hans C

    2014-10-01

    A large percentage of schizophrenic patients respond poorly to antipsychotic treatment. This could be explained by inefficient drug transport across the blood-brain barrier due to P-glycoprotein mediated efflux. P-glycoprotein activity and expression in the blood-brain barrier can be affected by inflammation and pharmacotherapy. We therefore investigated the effect of herpes simplex virus type-1 (HSV-1) induced neuroinflammation and antipsychotic treatment on P-glycoprotein activity. Rats were inoculated with HSV-1 or PBS (control) on day 0 and treated with saline, clozapine or risperidone from day 0 up until day 4 post-inoculation. Positron emission tomography with the P-glycoprotein substrate [11C]verapamil was used to assess P-glycoprotein activity at day 6 post-inoculation. Disease symptoms in HSV-1 inoculated rats increased over time and were not significantly affected by treatment. The volume of distribution (VT) of [11C]verapamil was significantly lower (10-22%) in HSV-1 inoculated rats than in control rats. In addition, antipsychotic treatment significantly affected the VT of [11C]verapamil in all brain regions, although this effect was drug dependent. In fact, VT of [11C]verapamil was significantly increased (22-39%) in risperidone treated rats in most brain regions when compared to clozapine treated rats and in midbrain when compared to saline treated rats. No interaction between HSV-1 inoculation and antipsychotic treatment on VT of [11C]verapamil was found. In this study we demonstrated that HSV-1 induced neuroinflammation increased and risperidone treatment decreased P-glycoprotein activity. This finding is of importance for the understanding of treatment resistance in schizophrenia, and warrants further investigation of the underlying mechanism and the importance in clinical practice. PMID:24973705

  11. Use of serologic tests to predict resistance to Canine distemper virus-induced disease in vaccinated dogs.

    PubMed

    Jensen, Wayne A; Totten, Janet S; Lappin, Michael R; Schultz, Ronald D

    2015-09-01

    The objective of the current study was to determine whether detection of Canine distemper virus (CDV)-specific serum antibodies correlates with resistance to challenge with virulent virus. Virus neutralization (VN) assay results were compared with resistance to viral challenge in 2 unvaccinated Beagle puppies, 9 unvaccinated Beagle dogs (4.4-7.2 years of age), and 9 vaccinated Beagle dogs (3.7-4.7 years of age). Eight of 9 (89%) unvaccinated adult dogs exhibited clinical signs after virus challenge, and 1 (13%) dog died. As compared to adult dogs, the 2 unvaccinated puppies developed more severe clinical signs and either died or were euthanized after challenge. In contrast, no clinical signs were detected after challenge of the 9 adult vaccinated dogs with post-vaccination intervals of up to 4.4 years. In vaccinated dogs, the positive and negative predictive values of VN assay results for resistance to challenge were 100% and 0%, respectively. Results indicate that dogs vaccinated with modified live CDV can be protected from challenge for ≤4.4 years postvaccination and that detection of virus-specific antibodies is predictive of whether dogs are resistant to challenge with virulent virus. Results also indicate that CDV infection in unvaccinated dogs results in age-dependent morbidity and mortality. Knowledge of age-dependent morbidity and mortality, duration of vaccine-induced immunity, and the positive and negative predictive values of detection of virus-specific serum antibodies are useful in development of rational booster vaccination intervals for the prevention of CDV-mediated disease in adult dogs. PMID:26330396

  12. Ultrastructural Characterization of Turnip Mosaic Virus-Induced Cellular Rearrangements Reveals Membrane-Bound Viral Particles Accumulating in Vacuoles

    PubMed Central

    Wan, Juan; Basu, Kaustuv; Mui, Jeannie; Vali, Hojatollah; Zheng, Huanquan

    2015-01-01

    ABSTRACT Positive-strand RNA [(+) RNA] viruses remodel cellular membranes to facilitate virus replication and assembly. In the case of turnip mosaic virus (TuMV), the viral membrane protein 6K2 plays an essential role in endomembrane alterations. Although 6K2-induced membrane dynamics have been widely studied by confocal microscopy, the ultrastructure of this remodeling has not been extensively examined. In this study, we investigated the formation of TuMV-induced membrane changes by chemical fixation and high-pressure freezing/freeze substitution (HPF/FS) for transmission electron microscopy at different times of infection. We observed the formation of convoluted membranes connected to rough endoplasmic reticulum (rER) early in the infection process, followed by the production of single-membrane vesicle-like (SMVL) structures at the midstage of infection. Both SMVL and double-membrane vesicle-like structures with electron-dense cores, as well as electron-dense bodies, were found late in the infection process. Immunogold labeling results showed that the vesicle-like structures were 6K2 tagged and suggested that only the SMVL structures were viral RNA replication sites. Electron tomography (ET) was used to regenerate a three-dimensional model of these vesicle-like structures, which showed that they were, in fact, tubules. Late in infection, we observed filamentous particle bundles associated with electron-dense bodies, which suggests that these are sites for viral particle assembly. In addition, TuMV particles were observed to accumulate in the central vacuole as membrane-associated linear arrays. Our work thus unravels the sequential appearance of distinct TuMV-induced membrane structures for viral RNA replication, viral particle assembly, and accumulation. IMPORTANCE Positive-strand RNA viruses remodel cellular membranes for different stages of the infection process, such as protein translation and processing, viral RNA synthesis, particle assembly, and virus transmission. The ultrastructure of turnip mosaic virus (TuMV)-induced membrane remodeling was investigated over several days of infection. The first change that was observed involved endoplasmic reticulum-connected convoluted membrane accumulation. This was followed by the formation of single-membrane tubules, which were shown to be viral RNA replication sites. Later in the infection process, double-membrane tubular structures were observed and were associated with viral particle bundles. In addition, TuMV particles were observed to accumulate in the central vacuole as membrane-associated linear arrays. This work thus unravels the sequential appearance of distinct TuMV-induced membrane structures for viral RNA replication, viral particle assembly, and accumulation. PMID:26423955

  13. Heat shock 70 protein interaction with Turnip mosaic virus RNA-dependent RNA polymerase within virus-induced membrane vesicles

    SciTech Connect

    Dufresne, Philippe J.; Thivierge, Karine; Cotton, Sophie; Beauchemin, Chantal; Ide, Christine; Ubalijoro, Eliane; Laliberte, Jean-Francois Fortin, Marc G.

    2008-04-25

    Tandem affinity purification was used in Arabidopsis thaliana to identify cellular interactors of Turnip mosaic virus (TuMV) RNA-dependent RNA polymerase (RdRp). The heat shock cognate 70-3 (Hsc70-3) and poly(A)-binding (PABP) host proteins were recovered and shown to interact with the RdRp in vitro. As previously shown for PABP, Hsc70-3 was redistributed to nuclear and membranous fractions in infected plants and both RdRp interactors were co-immunoprecipitated from a membrane-enriched extract using RdRp-specific antibodies. Fluorescently tagged RdRp and Hsc70-3 localized to the cytoplasm and the nucleus when expressed alone or in combination in Nicotiana benthamiana. However, they were redistributed to large perinuclear ER-derived vesicles when co-expressed with the membrane binding 6K-VPg-Pro protein of TuMV. The association of Hsc70-3 with the RdRp could possibly take place in membrane-derived replication complexes. Thus, Hsc70-3 and PABP2 are potentially integral components of the replicase complex and could have important roles to play in the regulation of potyviral RdRp functions.

  14. Infection of Murine Macrophages by Salmonella enterica Serovar Heidelberg Blocks Murine Norovirus Infectivity and Virus-induced Apoptosis

    PubMed Central

    Agnihothram, Sudhakar S.; Basco, Maria D. S.; Mullis, Lisa; Foley, Steven L.; Hart, Mark E.; Sung, Kidon; Azevedo, Marli P.

    2015-01-01

    Gastroenteritis caused by bacterial and viral pathogens constitutes a major public health threat in the United States accounting for 35% of hospitalizations. In particular, Salmonella enterica and noroviruses cause the majority of gastroenteritis infections, with emergence of sporadic outbreaks and incidence of increased infections. Although mechanisms underlying infections by these pathogens have been individually studied, little is known about the mechanisms regulating co-infection by these pathogens. In this study, we utilized RAW 264.7 murine macrophage cells to investigate the mechanisms governing co-infection with S. enterica serovar Heidelberg and murine norovirus (MNV). We demonstrate that infection of RAW 264.7 cells with S. enterica reduces the replication of MNV, in part by blocking virus entry early in the virus life cycle, and inducing antiviral cytokines later in the infection cycle. In particular, bacterial infection prior to, or during MNV infection affected virus entry, whereas MNV entry remained unaltered when the virus infection preceded bacterial invasion. This block in virus entry resulted in reduced virus replication, with the highest impact on replication observed during conditions of co-infection. In contrast, bacterial replication showed a threefold increase in MNV-infected cells, despite the presence of antibiotic in the medium. Most importantly, we present evidence that the infection of MNV-infected macrophages by S. enterica blocked MNV-induced apoptosis, despite allowing efficient virus replication. This apoptosis blockade was evidenced by reduction in DNA fragmentation and absence of poly-ADP ribose polymerase (PARP), caspase 3 and caspase 9 cleavage events. Our study suggests a novel mechanism of pathogenesis whereby initial co-infection with these pathogens could result in prolonged infection by either of these pathogens or both together. PMID:26658916

  15. Three-Dimensional Analysis of a Viral RNA Replication Complex Reveals a Virus-Induced Mini-Organelle

    PubMed Central

    Kopek, Benjamin G; Perkins, Guy; Miller, David J; Ellisman, Mark H; Ahlquist, Paul

    2007-01-01

    Positive-strand RNA viruses are the largest genetic class of viruses and include many serious human pathogens. All positive-strand RNA viruses replicate their genomes in association with intracellular membrane rearrangements such as single- or double-membrane vesicles. However, the exact sites of RNA synthesis and crucial topological relationships between relevant membranes, vesicle interiors, surrounding lumens, and cytoplasm generally are poorly defined. We applied electron microscope tomography and complementary approaches to flock house virus (FHV)–infected Drosophila cells to provide the first 3-D analysis of such replication complexes. The sole FHV RNA replication factor, protein A, and FHV-specific 5-bromouridine 5'-triphosphate incorporation localized between inner and outer mitochondrial membranes inside ∼50-nm vesicles (spherules), which thus are FHV-induced compartments for viral RNA synthesis. All such FHV spherules were outer mitochondrial membrane invaginations with interiors connected to the cytoplasm by a necked channel of ∼10-nm diameter, which is sufficient for ribonucleotide import and product RNA export. Tomographic, biochemical, and other results imply that FHV spherules contain, on average, three RNA replication intermediates and an interior shell of ∼100 membrane-spanning, self-interacting protein As. The results identify spherules as the site of protein A and nascent RNA accumulation and define spherule topology, dimensions, and stoichiometry to reveal the nature and many details of the organization and function of the FHV RNA replication complex. The resulting insights appear relevant to many other positive-strand RNA viruses and support recently proposed structural and likely evolutionary parallels with retrovirus and double-stranded RNA virus virions. PMID:17696647

  16. Protection Against Chikungunya Virus Induced Arthralgia Following Prophylactic Treatment with Adenovirus Vectored Interferon (mDEF201)

    PubMed Central

    Dagley, Ashley; Ennis, Jane; Turner, Jeffrey D.; Rood, Kerry A.; Van Wettere, Arnaud J.; Gowen, Brian B.; Julander, Justin G.

    2014-01-01

    Recent outbreaks of Chikungunya virus (CHIKV) infection have resulted in millions of cases of disease with significant morbidity. No approved antiviral treatments exist for the prevention or treatment of this viral disease. Infection with CHIKV results in a high rate of symptomatic disease that primarily includes a debilitating arthralgia. To model this cardinal disease manifestation, adult DBA/1J mice were challenged with CHIKV by footpad injection. Viremia and hind limb virus titers increased ~100-fold while spleen virus increased >1,000-fold within 1 day post-virus infection (dpi). Footpad swelling was measured over a 10-day period, with peak swelling observed between 6 and 7 dpi. Histology of the hind leg at the site of virus challenge showed evidence of myositis and synovitis starting on 5 dpi. Cytokine profiling of the hind limb at the site of inoculation revealed a biphasic inflammatory response represented by an increase in IL-6, MCP-1, IFN-γ, MIP-1α, RANTES, and IL-17. To investigate the prophylactic capacity of IFN, mice were treated with mDEF201, an adenovirus-vectored IFN-α. Intranasal administration of a single 107 pfu/ml dose of mDEF201 administered 21 days to 24 h prior to infection, significantly reduced footpad swelling, virus titers in the hind leg and spleen, and several inflammatory cytokines. Efficacy was not observed when treatment was initiated 24 h after virus challenge. This arthralgia model of CHIKV recapitulates relevant disease features commonly observed in human disease making it applicable to preclinical testing of therapies that target both viral replication and the associated joint disease. PMID:24833276

  17. The nucleoprotein of influenza A virus induces p53 signaling and apoptosis via attenuation of host ubiquitin ligase RNF43

    PubMed Central

    Nailwal, H; Sharma, S; Mayank, A K; Lal, S K

    2015-01-01

    The interplay between influenza virus and host factors to support the viral life cycle is well documented. Influenza A virus (IAV) proteins interact with an array of cellular proteins and hijack host pathways which are at the helm of cellular responses to facilitate virus invasion. The multifaceted nature of the ubiquitination pathway for protein regulation makes it a vulnerable target of many viruses including IAV. To this end we conducted a yeast two-hybrid screen to search for cellular ubiquitin ligases important for influenza virus replication. We identified host protein, RING finger protein 43 (RNF43), a RING-type E3 ubiquitin ligase, as a novel interactor of nucleoprotein (NP) of IAV and an essential partner to induce NP-driven p53-mediated apoptosis in IAV-infected cells. In this study, we demonstrate that IAV leads to attenuation of RNF43 transcripts and hence its respective protein levels in the cellular milieu whereas in RNF43 depleted cells, viral replication was escalated several folds. Moreover, RNF43 polyubiquitinates p53 which further leads to its destabilization resulting in a decrease in induction of the p53 apoptotic pathway, a hitherto unknown process targeted by NP for p53 stabilization and accumulation. Collectively, these results conclude that NP targets RNF43 to modulate p53 ubiquitination levels and hence causes p53 stabilization which is conducive to an enhanced apoptosis level in the host cells. In conclusion, our study unravels a novel strategy adopted by IAV for utilizing the much conserved ubiquitin proteasomal pathway. PMID:25996295

  18. In Ovo Delivery of CpG DNA Reduces Avian Infectious Laryngotracheitis Virus Induced Mortality and Morbidity

    PubMed Central

    Thapa, Simrika; Abdul Cader, Mohamed Sarjoon; Murugananthan, Kalamathy; Nagy, Eva; Sharif, Shayan; Czub, Markus; Abdul-Careem, Mohamed Faizal

    2015-01-01

    Endosomal toll-like receptor-21 and -9 sense CpG DNA activating production of pro-inflammatory mediators with antimicrobial effects. Here, we investigated the induction of antiviral response of in ovo delivered CpG DNA against infectious laryngotracheitis virus (ILTV) infection. We found that in ovo delivered CpG DNA significantly reduces ILTV infection pre-hatch correlating with the expression of IL-1β and increase of macrophages in lungs. As assessed in vitro, CpG DNA stimulated avian macrophages could be a potential source of IL-1β and other pro-inflammatory mediators. Since we also found that in ovo CpG DNA delivery maintains increased macrophages in the lungs post-hatch, we infected the chickens on the day of hatch with ILTV. We found that in ovo delivered CpG DNA significantly reduces mortality and morbidity resulting from ILTV infection encountered post-hatch. Thus, CpG DNA can be a candidate innate immune stimulant worthy of further investigation for the control of ILTV infection in chickens. PMID:25856635

  19. Prevention of immunodeficiency virus induced CD4+ T-cell depletion by prior infection with a non-pathogenic virus

    SciTech Connect

    TerWee, Julie A.; Carlson, Jennifer K.; Sprague, Wendy S.; Sondgeroth, Kerry S.; Shropshire, Sarah B.; Troyer, Jennifer L.; VandeWoude, Sue

    2008-07-20

    Immune dysregulation initiated by a profound loss of CD4+ T-cells is fundamental to HIV-induced pathogenesis. Infection of domestic cats with a non-pathogenic lentivirus prevalent in the puma (puma lentivirus, PLV or FIV{sub PCO}) prevented peripheral blood CD4+ T-cell depletion caused by subsequent virulent FIV infection. Maintenance of this critical population was not associated with a significant decrease in FIV viremia, lending support to the hypothesis that direct viral cytopathic effect is not the primary cause of immunodeficiency. Although this approach was analogous to immunization with a modified live vaccine, correlates of immunity such as a serum-neutralizing antibody or virus-specific T-cell proliferative response were not found in protected animals. Differences in cytokine transcription profile, most notably in interferon gamma, were observed between the protected and unprotected groups. These data provide support for the importance of non-adaptive enhancement of the immune response in the prevention of CD4+ T-cell loss.

  20. Hepatitis B virus induced coupling of deadhesion and migration of HepG2 cells on thermo-responsive polymer.

    PubMed

    Li, Xi; Feng, Huixing; Chen, Wei Ning; Chan, Vincent

    2010-03-01

    The unique physical property of thermo-responsive polymer (TRP) has recently prompted its increasing applications in tissue engineering. On the other hand, TRP has not been exploited for potential applications in quantitative cell screening against external stimulations. In this study, TRP is applied as a model system for elucidating the effect of HBV replication on the biophysical responses of HepG2 cells transfected by wild type HBV genome. Moreover, mutant HBV genome is designed to assess the specific activity of the SH3-binding domain of HBx during HBV replication. The adhesion contact recession and geometry transformation of HepG2 cells transfected with empty vector (pcDNA3.1 cells), wild type HBV (wtHBV cells) and mutant HBV genome (mHBV cells) are probed during the thermal transformation across lower solution critical temperature of TRP. In comparison with pcDNA3.1 cells and mHBV cells, the initial rate of reduction in degree of deformation and average adhesion energy for wtHBV cells is significantly increased. Interestingly, migration speed and persistence time of cells are found to be correlated with the cell deadhesion kinetics. Immuno-fluorescence microscopy demonstrates that HBV replication reduces the actin concentration and focal adhesions at cell periphery during the initial 30 min cell deadhesion. The results strongly suggested that HBV infection triggers the dynamic responses of HepG2 cells through the cytoskeleton remodeling and subsequent mechanochemical transduction. Overall, it is shown that TRP provides a convenient platform for quantifying biological stimulations on adherent cells. PMID:19944459