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Sample records for trigger rig-i-mediated ifn

  1. Negative regulation of RIG-I-mediated antiviral signaling by TRK-fused gene (TFG) protein

    International Nuclear Information System (INIS)

    Lee, Na-Rae; Shin, Han-Bo; Kim, Hye-In; Choi, Myung-Soo; Inn, Kyung-Soo

    2013-01-01

    Highlights: •TRK-fused gene product (TFG) interacts with TRIM25 upon viral infection. •TFG negatively regulates RIG-I mediated antiviral signaling. •TFG depletion leads to enhanced viral replication. •TFG act downstream of MAVS. -- Abstract: RIG-I (retinoic acid inducible gene I)-mediated antiviral signaling serves as the first line of defense against viral infection. Upon detection of viral RNA, RIG-I undergoes TRIM25 (tripartite motif protein 25)-mediated K63-linked ubiquitination, leading to type I interferon (IFN) production. In this study, we demonstrate that TRK-fused gene (TFG) protein, previously identified as a TRIM25-interacting protein, binds TRIM25 upon virus infection and negatively regulates RIG-I-mediated type-I IFN signaling. RIG-I-mediated IFN production and nuclear factor (NF)-κB signaling pathways were upregulated by the suppression of TFG expression. Furthermore, vesicular stomatitis virus (VSV) replication was significantly inhibited by small inhibitory hairpin RNA (shRNA)-mediated knockdown of TFG, supporting the suppressive role of TFG in RIG-I-mediated antiviral signaling. Interestingly, suppression of TFG expression increased not only RIG-I-mediated signaling but also MAVS (mitochondrial antiviral signaling protein)-induced signaling, suggesting that TFG plays a pivotal role in negative regulation of RNA-sensing, RIG-I-like receptor (RLR) family signaling pathways

  2. Duck RIG-I CARD Domain Induces the Chicken IFN-β by Activating NF-κB

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    Yang Chen

    2015-01-01

    Full Text Available Retinoic acid-inducible gene I- (RIG-I- like receptors (RLRs have recently been identified as cytoplasmic sensors for viral RNA. RIG-I, a member of RLRs family, plays an important role in innate immunity. Although previous investigations have proved that RIG-I is absent in chickens, it remains largely unknown whether the chicken can respond to RIG-I ligand. In this study, the eukaryotic expression vectors encoding duRIG-I full length (duck RIG-I, containing all domains, duRIG-I N-terminal (containing the two caspase activation and recruitment domain, CARDs, and duRIG-I C-terminal (containing helicase and regulatory domains labeled with 6*His tags were constructed successfully and detected by western blotting. Luciferase reporter assay and enzyme-linked immunosorbent assay (ELISA detected the duRIG-I significantly activated NF-κB and induced the expression of IFN-β when polyinosinic-polycytidylic acid (poly[I:C], synthetic double-stranded RNA challenges chicken embryonic fibroblasts cells (DF1 cells, while the duRIG-I was inactive in the absence of poly[I:C]. Further analysis revealed that the CARDs (duRIG-I-N induced IFN-β production regardless of the presence of poly[I:C], while the CARD-lacking duRIG-I (duRIG-I-C was not capable of activating downstream signals. These results indicate that duRIG-I CARD domain plays an important role in the induction of IFN-β and provide a basis for further studying the function of RIG-I in avian innate immunity.

  3. Toscana virus NSs protein inhibits the induction of type I interferon by interacting with RIG-I.

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    Gori-Savellini, Gianni; Valentini, Melissa; Cusi, Maria Grazia

    2013-06-01

    Toscana virus (TOSV) is a phlebovirus, of the Bunyaviridae family, that is responsible for central nervous system (CNS) injury in humans. Previous data have shown that the TOSV NSs protein is a gamma interferon (IFN-β) antagonist when transiently overexpressed in mammalian cells, inhibiting IRF-3 induction (G. Gori Savellini, F. Weber, C. Terrosi, M. Habjan, B. Martorelli, and M. G. Cusi, J. Gen. Virol. 92:71-79, 2011). In this study, we investigated whether an upstream sensor, which has a role in the signaling cascade leading to the production of type I IFN, was involved. We found a significant decrease in RIG-I protein levels in cells overexpressing TOSV NSs, suggesting that the nonstructural protein interacts with RIG-I and targets it for proteasomal degradation. In fact, the MG-132 proteasome inhibitor was able to restore IFN-β promoter activation in cells expressing NSs, demonstrating the existence of an evasion mechanism based on inhibition of the RIG-I sensor. Furthermore, a C-terminal truncated NSs protein (ΔNSs), although able to interact with RIG-I, did not affect the RIG-I-mediated IFN-β promoter activation, suggesting that the NSs domains responsible for RIG-I-mediated signaling and interaction with RIG-I are mapped on different regions. These results contribute to identify a novel mechanism for bunyaviruses by which TOSV NSs counteracts the early IFN response.

  4. Negative Role of RIG-I Serine 8 Phosphorylation in the Regulatin of Interferon-beta Production

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    E Nistal-Villan; M Gack; G Martinez-Delgado; N Maharaj; K Inn; H Yang; R Wang; A Aggarwal; J Jung; A Garcia-Sastre

    2011-12-31

    RIG-I (retinoic acid-inducible gene I) and TRIM25 (tripartite motif protein 25) have emerged as key regulatory factors to induce interferon (IFN)-mediated innate immune responses to limit viral replication. Upon recognition of viral RNA, TRIM25 E3 ligase binds the first caspase recruitment domain (CARD) of RIG-I and subsequently induces lysine 172 ubiquitination of the second CARD of RIG-I, which is essential for the interaction with downstream MAVS/IPS-1/CARDIF/VISA and, thereby, IFN-beta mRNA production. Although ubiquitination has emerged as a major factor involved in RIG-I activation, the potential contribution of other post-translational modifications, such as phosphorylation, to the regulation of RIG-I activity has not been addressed. Here, we report the identification of serine 8 phosphorylation at the first CARD of RIG-I as a negative regulatory mechanism of RIG-I-mediated IFN-beta production. Immunoblot analysis with a phosphospecific antibody showed that RIG-I serine 8 phosphorylation steady-state levels were decreased upon stimulation of cells with IFN-beta or virus infection. Substitution of serine 8 in the CARD RIG-I functional domain with phosphomimetic aspartate or glutamate results in decreased TRIM25 binding, RIG-I ubiquitination, MAVS binding, and downstream signaling. Finally, sequence comparison reveals that only primate species carry serine 8, whereas other animal species carry an asparagine, indicating that serine 8 phosphorylation may represent a primate-specific regulation of RIG-I activation. Collectively, these data suggest that the phosphorylation of RIG-I serine 8 operates as a negative switch of RIG-I activation by suppressing TRIM25 interaction, further underscoring the importance of RIG-I and TRIM25 connection in type I IFN signal transduction.

  5. Coxsackievirus cloverleaf RNA containing a 5' triphosphate triggers an antiviral response via RIG-I activation.

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    Qian Feng

    Full Text Available Upon viral infections, pattern recognition receptors (PRRs recognize pathogen-associated molecular patterns (PAMPs and stimulate an antiviral state associated with the production of type I interferons (IFNs and inflammatory markers. Type I IFNs play crucial roles in innate antiviral responses by inducing expression of interferon-stimulated genes and by activating components of the adaptive immune system. Although pegylated IFNs have been used to treat hepatitis B and C virus infections for decades, they exert substantial side effects that limit their use. Current efforts are directed toward the use of PRR agonists as an alternative approach to elicit host antiviral responses in a manner similar to that achieved in a natural infection. RIG-I is a cytosolic PRR that recognizes 5' triphosphate (5'ppp-containing RNA ligands. Due to its ubiquitous expression profile, induction of the RIG-I pathway provides a promising platform for the development of novel antiviral agents and vaccine adjuvants. In this study, we investigated whether structured RNA elements in the genome of coxsackievirus B3 (CVB3, a picornavirus that is recognized by MDA5 during infection, could activate RIG-I when supplied with 5'ppp. We show here that a 5'ppp-containing cloverleaf (CL RNA structure is a potent RIG-I inducer that elicits an extensive antiviral response that includes induction of classical interferon-stimulated genes, as well as type III IFNs and proinflammatory cytokines and chemokines. In addition, we show that prophylactic treatment with CVB3 CL provides protection against various viral infections including dengue virus, vesicular stomatitis virus and enterovirus 71, demonstrating the antiviral efficacy of this RNA ligand.

  6. RIG-I self-oligomerization is either dispensable or very transient for signal transduction.

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    Jade Louber

    Full Text Available Effective host defence against viruses depends on the rapid triggering of innate immunity through the induction of a type I interferon (IFN response. To this end, microbe-associated molecular patterns are detected by dedicated receptors. Among them, the RIG-I-like receptors RIG-I and MDA5 activate IFN gene expression upon sensing viral RNA in the cytoplasm. While MDA5 forms long filaments in vitro upon activation, RIG-I is believed to oligomerize after RNA binding in order to transduce a signal. Here, we show that in vitro binding of synthetic RNA mimicking that of Mononegavirales (Ebola, rabies and measles viruses leader sequences to purified RIG-I does not induce RIG-I oligomerization. Furthermore, in cells devoid of endogenous functional RIG-I-like receptors, after activation of exogenous Flag-RIG-I by a 62-mer-5'ppp-dsRNA or by polyinosinic:polycytidylic acid, a dsRNA analogue, or by measles virus infection, anti-Flag immunoprecipitation and specific elution with Flag peptide indicated a monomeric form of RIG-I. Accordingly, when using the Gaussia Luciferase-Based Protein Complementation Assay (PCA, a more sensitive in cellula assay, no RIG-I oligomerization could be detected upon RNA stimulation. Altogether our data indicate that the need for self-oligomerization of RIG-I for signal transduction is either dispensable or very transient.

  7. RIG-I-like receptor-induced IRF3 mediated pathway of apoptosis (RIPA: a new antiviral pathway

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    Saurabh Chattopadhyay

    2016-11-01

    Full Text Available Abstract The innate immune response is the first line of host defense to eliminate viral infection. Pattern recognition receptors in the cytosol, such as RIG-I-like receptors (RLR and Nod-like receptors (NLR, and membrane bound Toll like receptors (TLR detect viral infection and initiate transcription of a cohort of antiviral genes, including interferon (IFN and interferon stimulated genes (ISGs, which ultimately block viral replication. Another mechanism to reduce viral spread is through RIPA, the RLR-induced IRF3-mediated pathway of apoptosis, which causes infected cells to undergo premature death. The transcription factor IRF3 can mediate cellular antiviral responses by both inducing antiviral genes and triggering apoptosis through the activation of RIPA. The mechanism of IRF3 activation in RIPA is distinct from that of transcriptional activation; it requires linear polyubiquitination of specific lysine residues of IRF3. Using RIPA-active, but transcriptionally inactive, IRF3 mutants, it was shown that RIPA can prevent viral replication and pathogenesis in mice.

  8. The nucleocapsid proteins of mouse hepatitis virus and severe acute respiratory syndrome coronavirus share the same IFN-β antagonizing mechanism: attenuation of PACT-mediated RIG-I/ MDA5 activation.

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    Ding, Zhen; Fang, Liurong; Yuan, Shuangling; Zhao, Ling; Wang, Xunlei; Long, Siwen; Wang, Mohan; Wang, Dang; Foda, Mohamed Frahat; Xiao, Shaobo

    2017-07-25

    Coronaviruses (CoVs) are a huge threat to both humans and animals and have evolved elaborate mechanisms to antagonize interferons (IFNs). Nucleocapsid (N) protein is the most abundant viral protein in CoV-infected cells, and has been identified as an innate immunity antagonist in several CoVs, including mouse hepatitis virus (MHV) and severe acute respiratory syndrome (SARS)-CoV. However, the underlying molecular mechanism(s) remain unclear. In this study, we found that MHV N protein inhibited Sendai virus and poly(I:C)-induced IFN-β production by targeting a molecule upstream of retinoic acid-induced gene I (RIG-I) and melanoma differentiation gene 5 (MDA5). Further studies showed that both MHV and SARS-CoV N proteins directly interacted with protein activator of protein kinase R (PACT), a cellular dsRNA-binding protein that can bind to RIG-I and MDA5 to activate IFN production. The N-PACT interaction sequestered the association of PACT and RIG-I/MDA5, which in turn inhibited IFN-β production. However, the N proteins from porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV), which are also classified in the order Nidovirales, did not interact and counteract with PACT. Taken together, our present study confirms that both MHV and SARS-CoV N proteins can perturb the function of cellular PACT to circumvent the innate antiviral response. However, this strategy does not appear to be used by all CoVs N proteins.

  9. Modified vaccinia virus Ankara triggers type I IFN production in murine conventional dendritic cells via a cGAS/STING-mediated cytosolic DNA-sensing pathway.

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    Peihong Dai

    2014-04-01

    Full Text Available Modified vaccinia virus Ankara (MVA is an attenuated poxvirus that has been engineered as a vaccine against infectious agents and cancers. Our goal is to understand how MVA modulates innate immunity in dendritic cells (DCs, which can provide insights to vaccine design. In this study, using murine bone marrow-derived dendritic cells, we assessed type I interferon (IFN gene induction and protein secretion in response to MVA infection. We report that MVA infection elicits the production of type I IFN in murine conventional dendritic cells (cDCs, but not in plasmacytoid dendritic cells (pDCs. Transcription factors IRF3 (IFN regulatory factor 3 and IRF7, and the positive feedback loop mediated by IFNAR1 (IFN alpha/beta receptor 1, are required for the induction. MVA induction of type I IFN is fully dependent on STING (stimulator of IFN genes and the newly discovered cytosolic DNA sensor cGAS (cyclic guanosine monophosphate-adenosine monophosphate synthase. MVA infection of cDCs triggers phosphorylation of TBK1 (Tank-binding kinase 1 and IRF3, which is abolished in the absence of cGAS and STING. Furthermore, intravenous delivery of MVA induces type I IFN in wild-type mice, but not in mice lacking STING or IRF3. Treatment of cDCs with inhibitors of endosomal and lysosomal acidification or the lysosomal enzyme Cathepsin B attenuated MVA-induced type I IFN production, indicating that lysosomal enzymatic processing of virions is important for MVA sensing. Taken together, our results demonstrate a critical role of the cGAS/STING-mediated cytosolic DNA-sensing pathway for type I IFN induction in cDCs by MVA. We present evidence that vaccinia virulence factors E3 and N1 inhibit the activation of IRF3 and the induction of IFNB gene in MVA-infected cDCs.

  10. Measles Virus Suppresses RIG-I-like Receptor Activation in Dendritic Cells via DC-SIGN-Mediated Inhibition of PP1 Phosphatases

    NARCIS (Netherlands)

    Mesman, Annelies W.; Zijlstra-Willems, Esther M.; Kaptein, Tanja M.; de Swart, Rik L.; Davis, Meredith E.; Ludlow, Martin; Duprex, W. Paul; Gack, Michaela U.; Gringhuis, Sonja I.; Geijtenbeek, Teunis B. H.

    2014-01-01

    Dendritic cells (DCs) are targets of measles virus (MV) and play central roles in viral dissemination. However, DCs express the RIG-I-like receptors (RLRs) RIG-I and Mda5 that sense MV and induce type I interferon (IFN) production. Given the potency of this antiviral response, RLRs are tightly

  11. Measles virus suppresses RIG-I-like receptor activation in dendritic cells via DC-SIGN-mediated inhibition of PP1 phosphatases

    NARCIS (Netherlands)

    A.W. Mesman (Annelies ); E.M. Zijlstra-Willems (Esther); T.M. Kaptein (Tanja); R.L. de Swart (Rik); M.E. Davis (Meredith); M. Ludlow (Martin); W.P. Duprex (Paul); M.U. Gack (Michaela); S.I. Gringhuis (Sonja); T.B.H. Geijtenbeek (Teunis)

    2014-01-01

    textabstractDendritic cells (DCs) are targets of measles virus (MV) and play central roles in viral dissemination. However, DCs express the RIG-I-like receptors (RLRs) RIG-I and Mda5 that sense MV and induce type I interferon (IFN) production. Given the potency of this antiviral response, RLRs are

  12. Pigeon RIG-I Function in Innate Immunity against H9N2 IAV and IBDV

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    Wenping Xu

    2015-07-01

    Full Text Available Retinoic acid-inducible gene I (RIG-I, a cytosolic pattern recognition receptor (PRR, can sense various RNA viruses, including the avian influenza virus (AIV and infectious bursal disease virus (IBDV, and trigger the innate immune response. Previous studies have shown that mammalian RIG-I (human and mice and waterfowl RIG-I (ducks and geese are essential for type I interferon (IFN synthesis during AIV infection. Like ducks, pigeons are also susceptible to infection but are ineffective propagators and disseminators of AIVs, i.e., “dead end” hosts for AIVs and even highly pathogenic avian influenza (HPAI. Consequently, we sought to identify pigeon RIG-I and investigate its roles in the detection of A/Chicken/Shandong/ZB/2007 (H9N2 (ZB07, Gansu/Tianshui (IBDV TS and Beijing/CJ/1980 (IBDV CJ-801 strains in chicken DF-1 fibroblasts or human 293T cells. Pigeon mRNA encoding the putative pigeon RIG-I analogs was identified. The exogenous expression of enhanced green fluorescence protein (EGFP-tagged pigeon RIG-I and caspase activation and recruitment domains (CARDs, strongly induced antiviral gene (IFN-β, Mx, and PKR mRNA synthesis, decreased viral gene (M gene and VP2 mRNA expression, and reduced the viral titers of ZB07 and IBDV TS/CJ-801 virus strains in chicken DF-1 cells, but not in 293T cells. We also compared the antiviral abilities of RIG-I proteins from waterfowl (duck and goose and pigeon. Our data indicated that waterfowl RIG-I are more effective in the induction of antiviral genes and the repression of ZB07 and IBDV TS/CJ-801 strain replication than pigeon RIG-I. Furthermore, chicken melanoma differentiation associated gene 5(MDA5/ mitochondrial antiviral signaling (MAVS silencing combined with RIG-I transfection suggested that pigeon RIG-I can restore the antiviral response in MDA5-silenced DF-1 cells but not in MAVS-silenced DF-1 cells. In conclusion, these results demonstrated that pigeon RIG-I and CARDs have a strong antiviral

  13. RIG-I antiviral signaling drives interleukin-23 production and psoriasis-like skin disease.

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    Zhu, Huiyuan; Lou, Fangzhou; Yin, Qianqian; Gao, Yuanyuan; Sun, Yang; Bai, Jing; Xu, Zhenyao; Liu, Zhaoyuan; Cai, Wei; Ke, Fang; Zhang, Lingyun; Zhou, Hong; Wang, Hong; Wang, Gang; Chen, Xiang; Zhang, Hongxin; Wang, Zhugang; Ginhoux, Florent; Lu, Chuanjian; Su, Bing; Wang, Honglin

    2017-05-01

    Retinoic acid inducible-gene I (RIG-I) functions as one of the major sensors of RNA viruses. DDX58 , which encodes the RIG-I protein, has been newly identified as a susceptibility gene in psoriasis. Here, we show that the activation of RIG-I by 5'ppp-dsRNA, its synthetic ligand, directly causes the production of IL-23 and triggers psoriasis-like skin disease in mice. Repeated injections of IL-23 to the ears failed to induce IL-23 production and a full psoriasis-like skin phenotype, in either germ-free or RIG-I-deficient mice. RIG-I is also critical for a full development of skin inflammation in imiquimod (IMQ)-induced psoriasis-like mouse model. Furthermore, RIG-I-mediated endogenous IL-23 production was mainly confined to the CD11c + dendritic cells (DCs) via nuclear factor-kappa B (NF-κB) signaling, and stimulated RIG-I expression in an auto-regulatory feedback loop. Thus, our data suggest that the dysregulation in the antiviral immune responses of hosts through the innate pattern recognition receptors may trigger the skin inflammatory conditions in the pathophysiology of psoriasis. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  14. Both RIG-I and MDA5 detect alphavirus replication in concentration-dependent mode

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    Akhrymuk, Ivan; Frolov, Ilya; Frolova, Elena I., E-mail: evfrolova@UAB.edu

    2016-01-15

    Alphaviruses are a family of positive-strand RNA viruses that circulate on all continents between mosquito vectors and vertebrate hosts. Despite a significant public health threat, their biology is not sufficiently investigated, and the mechanisms of alphavirus replication and virus–host interaction are insufficiently understood. In this study, we have applied a variety of experimental systems to further understand the mechanism by which infected cells detect replicating alphaviruses. Our new data strongly suggest that activation of the antiviral response by alphavirus-infected cells is determined by the integrity of viral genes encoding proteins with nuclear functions, and by the presence of two cellular pattern recognition receptors (PRRs), RIG-I and MDA5. No type I IFN response is induced in their absence. The presence of either of these PRRs is sufficient for detecting virus replication. However, type I IFN activation in response to pathogenic alphaviruses depends on the basal levels of RIG-I or MDA5. - Highlights: • Both RIG-I and MDA5 detect alphavirus replication. • Alphavirus-induced transcriptional shutoff affects type I IFN induction. • Sensing of alphavirus replication by RIG-I and MDA5 depends on their concentrations. • High basal level of RIG-I and MDA5 allows IFN induction by pathogenic alphaviruses. • This dependence determines the discrepancy between the in vivo and in vitro data.

  15. Kinetic discrimination of self/non-self RNA by the ATPase activity of RIG-I and MDA5.

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    Louber, Jade; Brunel, Joanna; Uchikawa, Emiko; Cusack, Stephen; Gerlier, Denis

    2015-07-28

    The cytoplasmic RIG-like receptors are responsible for the early detection of viruses and other intracellular microbes by activating the innate immune response mediated by type I interferons (IFNs). RIG-I and MDA5 detect virus-specific RNA motifs with short 5'-tri/diphosphorylated, blunt-end double-stranded RNA (dsRNA) and >0.5-2 kb long dsRNA as canonical agonists, respectively. However, in vitro, they can bind to many RNA species, while in cells there is an activation threshold. As SF2 helicase/ATPase family members, ATP hydrolysis is dependent on co-operative RNA and ATP binding. Whereas simultaneous ATP and cognate RNA binding is sufficient to activate RIG-I by releasing autoinhibition of the signaling domains, the physiological role of the ATPase activity of RIG-I and MDA5 remains controversial. A cross-analysis of a rationally designed panel of RNA binding and ATPase mutants and truncated receptors, using type I IFN promoter activation as readout, allows us to refine our understanding of the structure-function relationships of RIG-I and MDA5. RNA activation of RIG-I depends on multiple critical RNA binding sites in its helicase domain as confirmed by functional evidence using novel mutations. We found that RIG-I or MDA5 mutants with low ATP hydrolysis activity exhibit constitutive activity but this was fully reverted when associated with mutations preventing RNA binding to the helicase domain. We propose that the turnover kinetics of the ATPase domain enables the discrimination of self/non-self RNA by both RIG-I and MDA5. Non-cognate, possibly self, RNA binding would lead to fast ATP turnover and RNA disassociation and thus insufficient time for the caspase activation and recruitment domains (CARDs) to promote downstream signaling, whereas tighter cognate RNA binding provides a longer time window for downstream events to be engaged. The exquisite fine-tuning of RIG-I and MDA5 RNA-dependent ATPase activity coupled to CARD release allows a robust IFN response

  16. Modulation of inflammasome-mediated pulmonary immune activation by type I IFNs protects bone marrow homeostasis during systemic responses to Pneumocystis lung infection.

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    Searles, Steve; Gauss, Katherine; Wilkison, Michelle; Hoyt, Teri R; Dobrinen, Erin; Meissner, Nicole

    2013-10-01

    Although acquired bone marrow failure (BMF) is considered a T cell-mediated autoimmune disease, possible innate immune defects as a cause for systemic immune deviations in response to otherwise innocuous infections have not been extensively explored. In this regard, we recently demonstrated an important role of type I IFNs in protecting hematopoiesis during systemic stress responses to the opportunistic fungal pathogen Pneumocystis in lymphocyte-deficient mice. Mice deficient in both lymphocytes and type I IFN receptor (IFrag(-/-) mice) develop rapidly progressing BMF due to accelerated bone marrow (BM) cell apoptosis associated with innate immune deviations in the BM in response to Pneumocystis lung infection. However, the communication pathway between lung and BM eliciting the induction of BMF in response to this strictly pulmonary infection has been unclear. In this study, we report that absence of an intact type I IFN system during Pneumocystis lung infection not only causes BMF in lymphocyte-deficient mice but also transient BM stress in lymphocyte-competent mice. This is associated with an exuberant systemic IFN-γ response. IFN-γ neutralization prevented Pneumocystis lung infection-induced BM depression in type I IFN receptor-deficient mice and prolonged neutrophil survival time in BM from IFrag(-/-) mice. IL-1β and upstream regulators of IFN-γ, IL-12, and IL-18 were also upregulated in lung and serum of IFrag(-/-) mice. In conjunction, there was exuberant inflammasome-mediated caspase-1 activation in pulmonary innate immune cells required for processing of IL-18 and IL-1β. Thus, absence of type I IFN signaling during Pneumocystis lung infection may result in deregulation of inflammasome-mediated pulmonary immune activation, causing systemic immune deviations triggering BMF in this model.

  17. Influence of type I IFN signaling on anti-MOG antibody-mediated demyelination

    DEFF Research Database (Denmark)

    Berg, Carsten Tue; Khorooshi, Reza M. H.; Asgari, Nasrin

    2017-01-01

    Background Antibodies with specificity for myelin oligodendrocyte glycoprotein (MOG) are implicated in multiple sclerosis and related diseases. The pathogenic importance of anti-MOG antibody in primary demyelinating pathology remains poorly characterized. Objective The objective of this study...... is to investigate whether administration of anti-MOG antibody would be sufficient for demyelination and to determine if type I interferon (IFN) signaling plays a similar role in anti-MOG antibody-mediated pathology, as has been shown for neuromyelitis optica-like pathology. Methods Purified IgG2a monoclonal anti...... demyelination in wild-type and IFNAR1-KO mice. Conclusions Anti-MOG antibody and complement was sufficient to induce callosal demyelination, and pathology was dependent on type I IFN. Induction of EAE in IFNAR1-KO mice overcame the dependence on type I IFN for anti-MOG and complement-mediated demyelination....

  18. Viral unmasking of cellular 5S rRNA pseudogene transcripts induces RIG-I-mediated immunity.

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    Chiang, Jessica J; Sparrer, Konstantin M J; van Gent, Michiel; Lässig, Charlotte; Huang, Teng; Osterrieder, Nikolaus; Hopfner, Karl-Peter; Gack, Michaela U

    2018-01-01

    The sensor RIG-I detects double-stranded RNA derived from RNA viruses. Although RIG-I is also known to have a role in the antiviral response to DNA viruses, physiological RNA species recognized by RIG-I during infection with a DNA virus are largely unknown. Using next-generation RNA sequencing (RNAseq), we found that host-derived RNAs, most prominently 5S ribosomal RNA pseudogene 141 (RNA5SP141), bound to RIG-I during infection with herpes simplex virus 1 (HSV-1). Infection with HSV-1 induced relocalization of RNA5SP141 from the nucleus to the cytoplasm, and virus-induced shutoff of host protein synthesis downregulated the abundance of RNA5SP141-interacting proteins, which allowed RNA5SP141 to bind RIG-I and induce the expression of type I interferons. Silencing of RNA5SP141 strongly dampened the antiviral response to HSV-1 and the related virus Epstein-Barr virus (EBV), as well as influenza A virus (IAV). Our findings reveal that antiviral immunity can be triggered by host RNAs that are unshielded following depletion of their respective binding proteins by the virus.

  19. A Promising IFN-Deficient System to Manufacture IFN-Sensitive Influenza Vaccine Virus.

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    Chen, Can; Fan, Wenhui; Li, Jing; Zheng, Weinan; Zhang, Shuang; Yang, Limin; Liu, Di; Liu, Wenjun; Sun, Lei

    2018-01-01

    Interferon (IFN)-sensitive and replication-incompetent influenza viruses are likely to be the alternatives to inactivated and attenuated virus vaccines. Some IFN-sensitive influenza vaccine candidates with modified non-structural protein 1 (NS1) are highly attenuated in IFN-competent hosts but induce robust antiviral immune responses. However, little research has been done on the manufacturability of these IFN-sensitive vaccine viruses. Here, RIG-I-knockout 293T cells were used to package the IFN-sensitive influenza A/WSN/33 (H1N1) virus expressing the mutant NS1 R38A/K41A. We found that the packaging efficiency of the NS1 R38A/K41A virus in RIG-I-knockout 293T cells was much higher than that in 293T cells. Moreover, the NS1 R38A/K41A virus almost lost its IFN antagonist activity and could no longer replicate in A549, MDCK, and Vero cells after 3-6 passages. This indicated that the replication of NS1 R38A/K41A virus is limited in conventional cells. Therefore, we further established a stable Vero cell line expressing the wild-type (WT) NS1 of the WSN virus, based on the Tet-On 3G system. The NS1 R38A/K41A virus was able to steadily propagate in this IFN-deficient cell line for at least 20 passages. In a mouse model, the NS1 R38A/K41A virus showed more than a 4-log reduction in lung virus titers compared to the WT virus at 3 and 5 days post infection. Furthermore, we observed that the NS1 R38A/K41A virus triggered high-level of IFN-α/β production in lung tissues and was eliminated from the host in a relatively short period of time. Additionally, this virus induced high-titer neutralizing antibodies against the WT WSN, A/Puerto Rico/8/1934 (PR8), or A/California/04/2009 (CA04) viruses and provided 100% protection against the WT WSN virus. Thus, we found that the replication of the NS1 R38A/K41A virus was limited in IFN-competent cells and mice. We also presented a promising IFN-deficient system, involving a RIG-I-knockout 293T cell line to package the IFN

  20. Viral Pseudo Enzymes Activate RIG-I via Deamidation to Evade Cytokine Production

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    He, Shanping; Zhao, Jun; Song, Shanshan; He, Xiaojing; Minassian, Arlet; Zhou, Yu; Zhang, Junjie; Brulois, Kevin; Wang, Yuqi; Cabo, Jackson; Zandi, Ebrahim; Liang, Chengyu; Jung, Jae U; Zhang, Xuewu; Feng, Pinghui

    2015-01-01

    SUMMARY RIG-I is a pattern recognition receptor that senses viral RNA and is crucial for host innate immune defense. Here we describe a mechanism of RIG-I activation through amidotransferase-mediated deamidation. We show that viral homologues of phosphoribosylformyglycinamide synthase (PFAS), although lacking intrinsic enzyme activity, recruit cellular PFAS to deamidate and activate RIG-I. Accordingly, depletion and biochemical inhibition of PFAS impair RIG-I deamidation and concomitant activation. Purified PFAS and viral homologue thereof deamidate RIG-I in vitro. Ultimately, herpesvirus hijacks activated RIG-I to avoid antiviral cytokine production; loss of RIG-I or inhibition of RIG-I deamidation results in elevated cytokine production. Together, these findings demonstrate a surprising mechanism of RIG-I activation that is mediated by an enzyme. PMID:25752576

  1. Distinct mechanisms of loss of IFN-gamma mediated HLA class I inducibility in two melanoma cell lines

    International Nuclear Information System (INIS)

    Rodríguez, Teresa; Méndez, Rosa; Del Campo, Ana; Jiménez, Pilar; Aptsiauri, Natalia; Garrido, Federico; Ruiz-Cabello, Francisco

    2007-01-01

    The inability of cancer cells to present antigen on the cell surface via MHC class I molecules is one of the mechanisms by which tumor cells evade anti-tumor immunity. Alterations of Jak-STAT components of interferon (IFN)-mediated signaling can contribute to the mechanism of cell resistance to IFN, leading to lack of MHC class I inducibility. Hence, the identification of IFN-γ-resistant tumors may have prognostic and/or therapeutic relevance. In the present study, we investigated a mechanism of MHC class I inducibility in response to IFN-γ treatment in human melanoma cell lines. Basal and IFN-induced expression of HLA class I antigens was analyzed by means of indirect immunofluorescence flow cytometry, Western Blot, RT-PCR, and quantitative real-time RT-PCR (TaqMan ® Gene Expression Assays). In demethylation studies cells were cultured with 5-aza-2'-deoxycytidine. Electrophoretic Mobility Shift Assay (EMSA) was used to assay whether IRF-1 promoter binding activity is induced in IFN-γ-treated cells. Altered IFNmediated HLA-class I induction was observed in two melanoma cells lines (ESTDAB-004 and ESTDAB-159) out of 57 studied, while treatment of these two cell lines with IFN-α led to normal induction of HLA class I antigen expression. Examination of STAT-1 in ESTDAB-004 after IFN-γ treatment demonstrated that the STAT-1 protein was expressed but not phosphorylated. Interestingly, IFN-α treatment induced normal STAT-1 phosphorylation and HLA class I expression. In contrast, the absence of response to IFN-γ in ESTDAB-159 was found to be associated with alterations in downstream components of the IFN-γ signaling pathway. We observed two distinct mechanisms of loss of IFN-γ inducibility of HLA class I antigens in two melanoma cell lines. Our findings suggest that loss of HLA class I induction in ESTDAB-004 cells results from a defect in the earliest steps of the IFN-γ signaling pathway due to absence of STAT-1 tyrosine-phosphorylation, while absence

  2. What Really Rigs Up RIG-I?

    Science.gov (United States)

    Barik, Sailen

    2016-01-01

    RIG-I (retinoic acid-inducible gene 1) is an archetypal member of the cytoplasmic DEAD-box dsRNA helicase family (RIG-I-like receptors or RLRs), the members of which play essential roles in the innate immune response of the metazoan cell. RIG-I functions as a pattern recognition receptor that detects nonself RNA as a pathogen-associated molecular pattern (PAMP). However, the exact molecular nature of the viral RNAs that act as a RIG-I ligand has remained a mystery and a matter of debate. In this article, we offer a critical review of the actual viral RNAs that act as PAMPs to activate RIG-I, as seen from the perspective of a virologist, including a recent report that the viral Leader-read-through transcript is a novel and effective RIG-I ligand. © 2016 S. Karger AG, Basel.

  3. Mutual antagonism between the Ebola virus VP35 protein and the RIG-I activator PACT determines infection outcome.

    Science.gov (United States)

    Luthra, Priya; Ramanan, Parameshwaran; Mire, Chad E; Weisend, Carla; Tsuda, Yoshimi; Yen, Benjamin; Liu, Gai; Leung, Daisy W; Geisbert, Thomas W; Ebihara, Hideki; Amarasinghe, Gaya K; Basler, Christopher F

    2013-07-17

    The cytoplasmic pattern recognition receptor RIG-I is activated by viral RNA and induces type I IFN responses to control viral replication. The cellular dsRNA binding protein PACT can also activate RIG-I. To counteract innate antiviral responses, some viruses, including Ebola virus (EBOV), encode proteins that antagonize RIG-I signaling. Here, we show that EBOV VP35 inhibits PACT-induced RIG-I ATPase activity in a dose-dependent manner. The interaction of PACT with RIG-I is disrupted by wild-type VP35, but not by VP35 mutants that are unable to bind PACT. In addition, PACT-VP35 interaction impairs the association between VP35 and the viral polymerase, thereby diminishing viral RNA synthesis and modulating EBOV replication. PACT-deficient cells are defective in IFN induction and are insensitive to VP35 function. These data support a model in which the VP35-PACT interaction is mutually antagonistic and plays a fundamental role in determining the outcome of EBOV infection. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Functional characterizations of RIG-I to GCRV and viral/bacterial PAMPs in grass carp Ctenopharyngodon idella.

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    Lijun Chen

    Full Text Available BACKGROUND: RIG-I (retinoic acid inducible gene-I is one of the key cytosolic pattern recognition receptors (PRRs for detecting nucleotide pathogen associated molecular patterns (PAMPs and mediating the induction of type I interferon and inflammatory cytokines in innate immune response. Though the mechanism is well characterized in mammals, the study of the accurate function of RIG-I in teleosts is still in its infancy. METHODOLOGY/PRINCIPAL FINDINGS: To clarify the functional characterizations of RIG-I in grass carp Ctenopharyngodon idella (CiRIG-I, six representative overexpression plasmids were constructed and transfected into C. idella kidney (CIK cell lines to obtain stably expressing recombinant proteins, respectively. A virus titer test and 96-well plate staining assay showed that all constructs exhibited the antiviral activity somewhat. The quantitative real-time RT-PCR (qRT-PCR demonstrated that mRNA expressions of CiIPS-1, CiIFN-I and CiMx2 were regulated by not only virus (GCRV or viral PAMP (poly(IC challenge but also bacterial PAMPs (LPS and PGN stimulation in the steadily transfected cells. The results showed that the full-length CiRIG-I played a key role in RLR pathway. The repressor domain (RD exerted an inhibitory function of the signaling channel under all utilized challenges. Caspase activation and recruitment domains (CARDs showed a positive role in GCRV and poly(I:C challenge. Helicase motifs were crucial for the signaling pathway upon LPS and PGN stimulation. Interestingly, ΔCARDs (CARDs deleted showed positive modulation in RIG-I signal transduction. CONCLUSIONS/SIGNIFICANCE: The results provided some novel insights into RIG-I sensing with a strikingly broad regulation in teleosts, responding not only to the dsRNA virus or synthetic dsRNA but also bacterial PAMPs.

  5. Endothelial RIG-I activation impairs endothelial function

    International Nuclear Information System (INIS)

    Asdonk, Tobias; Motz, Inga; Werner, Nikos; Coch, Christoph; Barchet, Winfried; Hartmann, Gunther; Nickenig, Georg; Zimmer, Sebastian

    2012-01-01

    Highlights: ► RIG-I activation impairs endothelial function in vivo. ► RIG-I activation alters HCAEC biology in vitro. ► EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 μg of the RIG-ligand 3pRNA (RNA with triphosphate at the 5′end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  6. Macrophage migration inhibitory factor triggers chemotaxis of CD74+CXCR2+ NKT cells in chemically induced IFN-γ-mediated skin inflammation.

    Science.gov (United States)

    Hsieh, Chia-Yuan; Chen, Chia-Ling; Lin, Yee-Shin; Yeh, Trai-Ming; Tsai, Tsung-Ting; Hong, Ming-Yuan; Lin, Chiou-Feng

    2014-10-01

    IFNmediates chemically induced skin inflammation; however, the mechanism by which IFN-γ-producing cells are recruited to the sites of inflammation remains undefined. Secretion of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, from damaged cells may promote immune cell recruitment. We hypothesized that MIF triggers an initial step in the chemotaxis of IFN-γ-producing cells in chemically induced skin inflammation. Using acute and chronic models of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin inflammation in mouse ears, MIF expression was examined, and its role in this process was investigated pharmacologically. The cell populations targeted by MIF, their receptor expression patterns, and the effects of MIF on cell migration were examined. TPA directly caused cytotoxicity accompanied by MIF release in mouse ear epidermal keratinocytes, as well as in human keratinocytic HaCaT cells. Treatment with the MIF antagonist (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester considerably attenuated TPA-induced ear swelling, leukocyte infiltration, epidermal cell proliferation, and dermal angiogenesis. Inhibition of MIF greatly diminished the dermal infiltration of IFN-γ(+) NKT cells, whereas the addition of exogenous TPA and MIF to NKT cells promoted their IFN-γ production and migration, respectively. MIF specifically triggered the chemotaxis of NKT cells via CD74 and CXCR2, and the resulting depletion of NKT cells abolished TPA-induced skin inflammation. In TPA-induced skin inflammation, MIF is released from damaged keratinocytes and then triggers the chemotaxis of CD74(+)CXCR2(+) NKT cells for IFN-γ production. Copyright © 2014 by The American Association of Immunologists, Inc.

  7. Endothelial RIG-I activation impairs endothelial function

    Energy Technology Data Exchange (ETDEWEB)

    Asdonk, Tobias, E-mail: tobias.asdonk@ukb.uni-bonn.de [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Motz, Inga; Werner, Nikos [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Coch, Christoph; Barchet, Winfried; Hartmann, Gunther [Institute for Clinical Chemistry and Clinical Pharmacology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Nickenig, Georg; Zimmer, Sebastian [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer RIG-I activation impairs endothelial function in vivo. Black-Right-Pointing-Pointer RIG-I activation alters HCAEC biology in vitro. Black-Right-Pointing-Pointer EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 {mu}g of the RIG-ligand 3pRNA (RNA with triphosphate at the 5 Prime end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  8. Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon Responses Mediated by Pattern Recognition Receptor Retinoic-Acid-Inducible Gene-I.

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    Seung Bum Park

    Full Text Available Hepatitis C virus (HCV actively evades host interferon (IFN responses but the mechanisms of how it does so are not completely understood. In this study, we present evidence for an HCV factor that contributes to the suppression of retinoic-acid-inducible gene-I (RIG-I-mediated IFN induction. Expression of frameshift/alternate reading frame protein (F/ARFP from HCV -2/+1 frame in Huh7 hepatoma cells suppressed type I IFN responses stimulated by HCV RNA pathogen-associated molecular pattern (PAMP and poly(IC. The suppression occurred independently of other HCV factors; and activation of interferon stimulated genes, TNFα, IFN-λ1, and IFN-λ2/3 was likewise suppressed by HCV F/ARFP. Point mutations in the full-length HCV sequence (JFH1 genotype 2a strain were made to introduce premature termination codons in the -2/+1 reading frame coding for F/ARFP while preserving the original reading frame, which enhanced IFNα and IFNβ induction by HCV. The potentiation of IFN response by the F/ARFP mutations was diminished in Huh7.5 cells, which already have a defective RIG-I, and by decreasing RIG-I expression in Huh7 cells. Furthermore, adding F/ARFP back via trans-complementation suppressed IFN induction in the F/ARFP mutant. The F/ARFP mutants, on the other hand, were not resistant to exogenous IFNα. Finally, HCV-infected human liver samples showed significant F/ARFP antibody reactivity, compared to HCV-uninfected control livers. Therefore, HCV F/ARFP likely cooperates with other viral factors to suppress type I and III IFN induction occurring through the RIG-I signaling pathway. This study identifies a novel mechanism of pattern recognition receptor modulation by HCV and suggests a biological function of the HCV alternate reading frame in the modulation of host innate immunity.

  9. Rotavirus nonstructural protein 1 antagonizes innate immune response by interacting with retinoic acid inducible gene I

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    Qin Lan

    2011-12-01

    Full Text Available Abstract Background The nonstructural protein 1 (NSP1 of rotavirus has been reported to block interferon (IFN signaling by mediating proteasome-dependent degradation of IFN-regulatory factors (IRFs and (or the β-transducin repeat containing protein (β-TrCP. However, in addition to these targets, NSP1 may subvert innate immune responses via other mechanisms. Results The NSP1 of rotavirus OSU strain as well as the IRF3 binding domain truncated NSP1 of rotavirus SA11 strain are unable to degrade IRFs, but can still inhibit host IFN response, indicating that NSP1 may target alternative host factor(s other than IRFs. Overexpression of NSP1 can block IFN-β promoter activation induced by the retinoic acid inducible gene I (RIG-I, but does not inhibit IFN-β activation induced by the mitochondrial antiviral-signaling protein (MAVS, indicating that NSP1 may target RIG-I. Immunoprecipitation experiments show that NSP1 interacts with RIG-I independent of IRF3 binding domain. In addition, NSP1 induces down-regulation of RIG-I in a proteasome-independent way. Conclusions Our findings demonstrate that inhibition of RIG-I mediated type I IFN responses by NSP1 may contribute to the immune evasion of rotavirus.

  10. Identification of Two Subgroups of Type I IFNs in Perciforme Fish Large Yellow Croaker Larimichthys crocea Provides Novel Insights into Function and Regulation of Fish Type I IFNs

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    Yang Ding

    2016-09-01

    Full Text Available Like mammals, fish possess an interferon regulatory factor 3 (IRF3/IRF7-dependent type I IFN responses, but the exact mechanism by which IRF3/IRF7 regulate the type I IFNs remains largely unknown. In this study, we identified two type I IFNs in the Perciforme fish large yellow croaker Larimichthys crocea, one of which belongs to the fish IFNd subgroup, and the other is assigned to a novel subgroup of group I IFNs in fish, tentatively termed IFNh. The two IFN genes are constitutively expressed in all examined tissues, but with varied expression levels. Both IFN genes can be rapidly induced in head kidney and spleen tissues by polyinosinic-polycytidylic acid. The recombinant IFNh was shown to be more potent to trigger a rapid induction of the antiviral genes MxA and PKR than the IFNd, suggesting that they may play distinct roles in regulating early antiviral immunity. Strikingly, IFNd, but not IFNh, could induce the gene expression of itself and IFNh through a positive feedback loop mediated by the IFNd-dependent activation of IRF3 and IRF7. Furthermore, our data demonstrate that the induction of IFNd can be enhanced by the dimeric formation of IRF3 and IRF7, while the IFNh expression mainly involves IRF3. Taken together, our findings demonstrate that the IFN responses are diverse in fish and are likely to be regulated by distinct mechanisms.

  11. Functional effects of Toll-like receptor (TLR3, 7, 9, RIG-I and MDA-5 stimulation in nasal epithelial cells.

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    Lotta Tengroth

    Full Text Available The human nasal epithelium is an important physical barrier, and a part of the innate immune defense that protect against pathogens. The epithelial cells recognize microbial components by pattern-recognition receptors (PRRs, and thereby trigger an immune response. Even though TLR3, TLR7, TLR9, RIG-I and MDA-5 are all known to respond to viral stimulation, their potential role in chronic airway inflammation triggered by local cytokine release remains to be established.mRNA and corresponding protein expression of TLR3, TLR7, TLR9, RIG-I and MDA-5 were analyzed in nasal biopsies and various upper airway epithelial cell lines using real-time reverse transcription PCR, immunohistochemistry and flow cytometry. Ligand induced, cytokine release, was evaluated with ELISA.Nasal biopsies were found to express TLR3, TLR7, TLR9, RIG-I and MDA-5, with the most abundant expression in the surface epithelium. These receptors were verified in primary human nasal epithelial cell (HNEC as well as in the airway epithelial cell lines Detroit-562 and FaDu. Poly(I:C (TLR3 and R-837 (TLR7 stimulation increased secretion of IL-6 and GM-CSF from the nasal mucosa and the epithelial cell lines. CpG (TLR9 stimulation caused release of IL-8 in the nasal mucosa and in FaDu. Poly(I:C/LyoVec (RIG-I/MDA-5 stimulation activated the secretion of IFN-β in the nasal mucosa. A corresponding release was also detected from HNEC and Detroit-562.The nasal epithelium has the ability to recognize viral intrusion through TLR and RLR receptors, and the subsequent response might have a role in exacerbation of inflammatory diseases like allergic rhinitis and chronic rhinosinusitis.

  12. The MEK1/2-ERK Pathway Inhibits Type I IFN Production in Plasmacytoid Dendritic Cells

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    Vaclav Janovec

    2018-02-01

    Full Text Available Recent studies have reported that the crosslinking of regulatory receptors (RRs, such as blood dendritic cell antigen 2 (BDCA-2 (CD303 or ILT7 (CD85g, of plasmacytoid dendritic cells (pDCs efficiently suppresses the production of type I interferons (IFN-I, α/β/ω and other cytokines in response to toll-like receptor 7 and 9 (TLR7/9 ligands. The exact mechanism of how this B cell receptor (BCR-like signaling blocks TLR7/9-mediated IFN-I production is unknown. Here, we stimulated BCR-like signaling by ligation of RRs with BDCA-2 and ILT7 mAbs, hepatitis C virus particles, or BST2 expressing cells. We compared BCR-like signaling in proliferating pDC cell line GEN2.2 and in primary pDCs from healthy donors, and addressed the question of whether pharmacological targeting of BCR-like signaling can antagonize RR-induced pDC inhibition. To this end, we tested the TLR9-mediated production of IFN-I and proinflammatory cytokines in pDCs exposed to a panel of inhibitors of signaling molecules involved in BCR-like, MAPK, NF-ĸB, and calcium signaling pathways. We found that MEK1/2 inhibitors, PD0325901 and U0126 potentiated TLR9-mediated production of IFN-I in GEN2.2 cells. More importantly, MEK1/2 inhibitors significantly increased the TLR9-mediated IFN-I production blocked in both GEN2.2 cells and primary pDCs upon stimulation of BCR-like or phorbol 12-myristate 13-acetate-induced protein kinase C (PKC signaling. Triggering of BCR-like and PKC signaling in pDCs resulted in an upregulation of the expression and phoshorylation of c-FOS, a downstream gene product of the MEK1/2-ERK pathway. We found that the total level of c-FOS was higher in proliferating GEN2.2 cells than in the resting primary pDCs. The PD0325901-facilitated restoration of the TLR9-mediated IFN-I production correlated with the abrogation of MEK1/2-ERK-c-FOS signaling. These results indicate that the MEK1/2-ERK pathway inhibits TLR9-mediated type I IFN production in pDCs and that

  13. Proteolysis of MDA5 and IPS-1 is not required for inhibition of the type I IFN response by poliovirus.

    Science.gov (United States)

    Kotla, Swathi; Gustin, Kurt E

    2015-10-06

    The type I interferon (IFN) response is a critical component of the innate immune response to infection by RNA viruses and is initiated via recognition of viral nucleic acids by RIG-like receptors (RLR). Engagement of these receptors in the cytoplasm initiates a signal transduction pathway leading to activation of the transcription factors NF-κB, ATF-2 and IRF-3 that coordinately upregulate transcription of type I IFN genes, such as that encoding IFN-β. In this study the impact of poliovirus infection on the type I interferon response has been examined. The type I IFN response was assessed by measuring IFN-β mRNA levels using qRT-PCR and normalizing to levels of β-actin mRNA. The status of host factors involved in activation of the type I IFN response was examined by immunoblot, immunofluorescence microcopy and qRT-PCR. The results show that poliovirus infection results in induction of very low levels of IFN-β mRNA despite clear activation of NF-κB and ATF-2. In contrast, analysis of IRF-3 revealed no transcriptional induction of an IRF-3-responsive promoter or homodimerization of IRF-3 indicating it is not activated in poliovirus-infected cells. Exposure of poliovirus-infected cells to poly(I:C) results in lower levels of IFN-β mRNA synthesis and IRF-3 activation compared to mock-infected cells. Analysis of MDA-5 and IPS-1 revealed that these components of the RLR pathway were largely intact at times when the type I IFN response was suppressed. Collectively, these results demonstrate that poliovirus infection actively suppresses the host type I interferon response by blocking activation of IRF-3 and suggests that this is not mediated by cleavage of MDA-5 or IPS-1.

  14. Cellular La protein shields nonsegmented negative-strand RNA viral leader RNA from RIG-I and enhances virus growth by diverse mechanisms.

    Science.gov (United States)

    Bitko, Vira; Musiyenko, Alla; Bayfield, Mark A; Maraia, Richard J; Barik, Sailen

    2008-08-01

    The La antigen (SS-B) associates with a wide variety of cellular and viral RNAs to affect gene expression in multiple systems. We show that La is the major cellular protein found to be associated with the abundant 44-nucleotide viral leader RNA (leRNA) early after infection with respiratory syncytial virus (RSV), a nonsegmented negative-strand RNA virus. Consistent with this, La redistributes from the nucleus to the cytoplasm in RSV-infected cells. Upon RNA interference knockdown of La, leRNA is redirected to associate with the RNA-binding protein RIG-I, a known activator of interferon (IFN) gene expression, and this is accompanied by the early induction of IFN mRNA. These results suggest that La shields leRNA from RIG-I, abrogating the early viral activation of type I IFN. We mapped the leRNA binding function to RNA recognition motif 1 of La and showed that while wild-type La greatly enhanced RSV growth, a La mutant defective in RSV leRNA binding also did not support RSV growth. Comparative studies of RSV and Sendai virus and the use of IFN-negative Vero cells indicated that La supports the growth of nonsegmented negative-strand RNA viruses by both IFN suppression and a potentially novel IFN-independent mechanism.

  15. TANK-Binding Kinase 1 (TBK1 Isoforms Negatively Regulate Type I Interferon Induction by Inhibiting TBK1-IRF3 Interaction and IRF3 Phosphorylation

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    Yi Wei Hu

    2018-01-01

    Full Text Available TANK-binding kinase 1 (TBK1 is an important serine/threonine-protein kinase that mediates phosphorylation and nuclear translocation of IRF3, which contributes to induction of type I interferons (IFNs in the innate antiviral response. In mammals, TBK1 spliced isoform negatively regulates the virus-triggered IFN-β signaling pathway by disrupting the interaction between retinoic acid-inducible gene I (RIG-I and mitochondria antiviral-signaling protein (MAVS. However, it is still unclear whether alternative splicing patterns and the function of TBK1 isoform(s exist in teleost fish. In this study, we identify two alternatively spliced isoforms of TBK1 from zebrafish, termed TBK1_tv1 and TBK1_tv2. Both TBK1_tv1 and TBK1_tv2 contain an incomplete STKc_TBK1 domain. Moreover, the UBL_TBK1_like domain is also missing for TBK1_tv2. TBK1_tv1 and TBK1_tv2 are expressed in zebrafish larvae. Overexpression of TBK1_tv1 and TBK1_tv2 inhibits RIG-I-, MAVS-, TBK1-, and IRF3-mediated activation of IFN promoters in response to spring viremia of carp virus infection. Also, TBK1_tv1 and TBK1_tv2 inhibit expression of IFNs and IFN-stimulated genes induced by MAVS and TBK1. Mechanistically, TBK1_tv1 and TBK1_tv2 competitively associate with TBK1 and IRF3 to disrupt the formation of a functional TBK1-IRF3 complex, impeding the phosphorylation of IRF3 mediated by TBK1. Collectively, these results demonstrate that TBK1 spliced isoforms are dominant negative regulators in the RIG-I/MAVS/TBK1/IRF3 antiviral pathway by targeting the functional TBK1-IRF3 complex formation. Identification and functional characterization of piscine TBK1 spliced isoforms may contribute to understanding the role of TBK1 expression in innate antiviral response.

  16. Triggering of the dsRNA sensors TLR3, MDA5, and RIG-I induces CD55 expression in synovial fibroblasts.

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    Olga N Karpus

    Full Text Available CD55 (decay-accelerating factor is a complement-regulatory protein highly expressed on fibroblast-like synoviocytes (FLS. CD55 is also a ligand for CD97, an adhesion-type G protein-coupled receptor abundantly present on leukocytes. Little is known regarding the regulation of CD55 expression in FLS.FLS isolated from arthritis patients were stimulated with pro-inflammatory cytokines and Toll-like receptor (TLR ligands. Transfection with polyinosinic-polycytidylic acid (poly(I:C and 5'-triphosphate RNA were used to activate the cytoplasmic double-stranded (dsRNA sensors melanoma differentiation-associated gene 5 (MDA5 and retinoic acid-inducible gene-I (RIG-I. CD55 expression, cell viability, and binding of CD97-loaded beads were quantified by flow cytometry.CD55 was expressed at equal levels on FLS isolated from patients with rheumatoid arthritis (RA, osteoarthritis, psoriatic arthritis and spondyloarthritis. CD55 expression in RA FLS was significantly induced by IL-1β and especially by the TLR3 ligand poly(I:C. Activation of MDA5 and RIG-I also enhanced CD55 expression. Notably, activation of MDA5 dose-dependently induced cell death, while triggering of TLR3 or RIG-I had a minor effect on viability. Upregulation of CD55 enhanced the binding capacity of FLS to CD97-loaded beads, which could be blocked by antibodies against CD55.Activation of dsRNA sensors enhances the expression of CD55 in cultured FLS, which increases the binding to CD97. Our findings suggest that dsRNA promotes the interaction between FLS and CD97-expressing leukocytes.

  17. Tetherin Suppresses Type I Interferon Signaling by Targeting MAVS for NDP52-Mediated Selective Autophagic Degradation in Human Cells.

    Science.gov (United States)

    Jin, Shouheng; Tian, Shuo; Luo, Man; Xie, Weihong; Liu, Tao; Duan, Tianhao; Wu, Yaoxing; Cui, Jun

    2017-10-19

    Tetherin (BST2/CD317) is an interferon-inducible antiviral factor known for its ability to block the release of enveloped viruses from infected cells. Yet its role in type I interferon (IFN) signaling remains poorly defined. Here, we demonstrate that Tetherin is a negative regulator of RIG-I like receptor (RLR)-mediated type I IFN signaling by targeting MAVS. The induction of Tetherin by type I IFN accelerates MAVS degradation via ubiquitin-dependent selective autophagy in human cells. Moreover, Tetherin recruits E3 ubiquitin ligase MARCH8 to catalyze K27-linked ubiquitin chains on MAVS at lysine 7, which serves as a recognition signal for NDP52-dependent autophagic degradation. Taken together, our findings reveal a negative feedback loop of RLR signaling generated by Tetherin-MARCH8-MAVS-NDP52 axis and provide insights into a better understanding of the crosstalk between selective autophagy and optimal deactivation of type I IFN signaling. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Coxsackievirus cloverleaf RNA containing a 5' triphosphate triggers an antiviral response via RIG-I activation

    NARCIS (Netherlands)

    Feng, Qian; Langereis, Martijn A; Olagnier, David; Chiang, Cindy; van de Winkel, Roel; van Essen, Peter; Zoll, Jan; Hiscott, John; van Kuppeveld, Frank J M

    2014-01-01

    Upon viral infections, pattern recognition receptors (PRRs) recognize pathogen-associated molecular patterns (PAMPs) and stimulate an antiviral state associated with the production of type I interferons (IFNs) and inflammatory markers. Type I IFNs play crucial roles in innate antiviral responses by

  19. Foot-and-mouth disease virus non-structural protein 3A inhibits the interferon-β signaling pathway

    Science.gov (United States)

    Li, Dan; Lei, Caoqi; Xu, Zhisheng; Yang, Fan; Liu, Huanan; Zhu, Zixiang; Li, Shu; Liu, Xiangtao; Shu, Hongbing; Zheng, Haixue

    2016-01-01

    Foot-and-mouth disease virus (FMDV) is the etiological agent of FMD, which affects cloven-hoofed animals. The pathophysiology of FMDV has not been fully understood and the evasion of host innate immune system is still unclear. Here, the FMDV non-structural protein 3A was identified as a negative regulator of virus-triggered IFN-β signaling pathway. Overexpression of the FMDV 3A inhibited Sendai virus-triggered activation of IRF3 and the expressions of RIG-I/MDA5. Transient transfection and co-immunoprecipitation experiments suggested that FMDV 3A interacts with RIG-I, MDA5 and VISA, which is dependent on the N-terminal 51 amino acids of 3A. Furthermore, 3A also inhibited the expressions of RIG-I, MDA5, and VISA by disrupting their mRNA levels. These results demonstrated that 3A inhibits the RLR-mediated IFN-β induction and uncovered a novel mechanism by which the FMDV 3A protein evades the host innate immune system. PMID:26883855

  20. Accessory factors of cytoplasmic viral RNA sensors required for antiviral innate immune response

    Directory of Open Access Journals (Sweden)

    Hiroyuki eOshiumi

    2016-05-01

    Full Text Available Type I interferon (IFN induces many antiviral factors in host cells. RIG-I-like receptors (RLRs are cytoplasmic viral RNA sensors that trigger the signal to induce the innate immune response that includes type I IFN production. RIG-I and MDA5 are RLRs that form nucleoprotein filaments along viral double-stranded RNA, resulting in the activation of MAVS adaptor molecule. The MAVS protein forms a prion-like aggregation structure, leading to type I IFN production. RIG-I and MDA5 undergo post-translational modification. TRIM25 and Riplet ubiquitin ligases deliver a K63-linked polyubiquitin moiety to the RIG-I N-terminal caspase activation and recruitment domains (CARDs and C-terminal region; the polyubiquitin chain then stabilizes the two-CARD tetramer structure required for MAVS assembly. MDA5 activation is regulated by phosphorylation. RIOK3 is a protein kinase that phosphorylates the MDA5 protein in a steady state, and PP1α/γ dephosphorylate this protein, resulting in its activation. RIG-I and MDA5 require cytoplasmic RNA helicases for their efficient activation. LGP2, another RLR, is an RNA helicase involved in RLR signaling. This protein does not possess N-terminal CARDs and thus cannot trigger downstream signaling by itself. Recent studies have revealed that this protein modulates MDA5 filament formation, resulting in enhanced type I IFN production. Several other cytoplasmic RNA helicases are involved in RLR signaling. DDX3, DHX29, DHX36, and DDX60 RNA helicases have been reported to be involved in RLR-mediated type I IFN production after viral infection. However, the underlying mechanism is largely unknown. Future studies are required to reveal the role of RNA helicases in the RLR signaling pathway.

  1. Expression and Functional Characterization of the RIG-I-Like Receptors MDA5 and LGP2 in Rainbow Trout (Oncorhynchus mykiss) ▿ †

    Science.gov (United States)

    Chang, Mingxian; Collet, Bertrand; Nie, Pin; Lester, Katherine; Campbell, Scott; Secombes, Christopher J.; Zou, Jun

    2011-01-01

    The retinoic acid-inducible gene I (RIG-I)-like receptors (RLR) comprise three homologues: RIG-I, melanoma differentiation-associated gene 5 (MDA5), and laboratory of genetics and physiology 2 (LGP2). They activate the host interferon (IFN) system upon recognition of viral RNA pathogen-associated molecular patterns (PAMPs) in the cytoplasm. Bioinformatic analysis of the sequenced vertebrate genomes suggests that the cytosolic surveillance system is conserved in lower vertebrates, and recent functional studies have confirmed that RIG-I is important to fish antiviral immunity. In this study, we have identified MDA5 and LGP2 homologues from rainbow trout Oncorhynchus mykiss and an additional LGP2 variant with an incomplete C-terminal domain of RIG-I. Trout MDA5 and LGP2 were constitutively produced in fibroblast and macrophage cell lines and upregulated by poly(I:C), recombinant IFN, or infection by RNA viruses (viral hemorrhagic septicemia virus and salmon alphavirus) with a single-stranded positive or negative genome. Overexpression of MDA5 and LGP2 but not of the LGP2 variant resulted in significant accumulation of Mx transcripts in cultured cells, which correlated with a marked enhancement of protection against viral infection. These results demonstrate that both MDA5 and LGP2 are important RLRs in host surveillance against infection of both negative and positive viruses and that the LGP2 variant with a deletion of 54 amino acids at the C terminus acts as a negative regulator for LGP2-elicited antiviral signaling by competing for the viral RNA PAMPs. Interestingly, MDA5 expression was not affected by overexpressed LGP2 in transfected cells and vice versa, suggesting that they likely act in parallel as positive regulators for IFN production. PMID:21680521

  2. Getting “Inside” Type I IFNs: Type I IFNs in Intracellular Bacterial Infections

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    Deann T. Snyder

    2017-01-01

    Full Text Available Type I interferons represent a unique and complex group of cytokines, serving many purposes during innate and adaptive immunity. Discovered in the context of viral infections, type I IFNs are now known to have myriad effects in infectious and autoimmune disease settings. Type I IFN signaling during bacterial infections is dependent on many factors including whether the infecting bacterium is intracellular or extracellular, as different signaling pathways are activated. As such, the repercussions of type I IFN induction can positively or negatively impact the disease outcome. This review focuses on type I IFN induction and downstream consequences during infection with the following intracellular bacteria: Chlamydia trachomatis, Listeria monocytogenes, Mycobacterium tuberculosis, Salmonella enterica serovar Typhimurium, Francisella tularensis, Brucella abortus, Legionella pneumophila, and Coxiella burnetii. Intracellular bacterial infections are unique because the bacteria must avoid, circumvent, and even co-opt microbial “sensing” mechanisms in order to reside and replicate within a host cell. Furthermore, life inside a host cell makes intracellular bacteria more difficult to target with antibiotics. Because type I IFNs are important immune effectors, modulating this pathway may improve disease outcomes. But first, it is critical to understand the context-dependent effects of the type I IFN pathway in intracellular bacterial infections.

  3. The E3 Ubiquitin Ligase TRIM40 Attenuates Antiviral Immune Responses by Targeting MDA5 and RIG-I

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    Chunyuan Zhao

    2017-11-01

    Full Text Available Retinoic acid-inducible gene-I (RIG-I-like receptors (RLRs, including melanoma differentiation-associated gene 5 (MDA5 and RIG-I, are crucial for host recognition of non-self RNAs, especially viral RNA. Thus, the expression and activation of RLRs play fundamental roles in eliminating the invading RNA viruses and maintaining immune homeostasis. However, how RLR expression is tightly regulated remains to be further investigated. In this study, we identified a major histocompatibility complex (MHC-encoded gene, tripartite interaction motif 40 (TRIM40, as a suppressor of RLR signaling by directly targeting MDA5 and RIG-I. TRIM40 binds to MDA5 and RIG-I and promotes their K27- and K48-linked polyubiquitination via its E3 ligase activity, leading to their proteasomal degradation. TRIM40 deficiency enhances RLR-triggered signaling. Consequently, TRIM40 deficiency greatly enhances antiviral immune responses and decreases viral replication in vivo. Thus, we demonstrate that TRIM40 limits RLR-triggered innate activation, suggesting TRIM40 as a potential therapeutic target for the control of viral infection.

  4. IRF-3, IRF-5, and IRF-7 coordinately regulate the type I IFN response in myeloid dendritic cells downstream of MAVS signaling.

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    Helen M Lazear

    2013-01-01

    Full Text Available Although the transcription factors IRF-3 and IRF-7 are considered master regulators of type I interferon (IFN induction and IFN stimulated gene (ISG expression, Irf3(-/-×Irf7(-/- double knockout (DKO myeloid dendritic cells (mDC produce relatively normal levels of IFN-β after viral infection. We generated Irf3(-/-×Irf5(-/-×Irf7(-/- triple knockout (TKO mice to test whether IRF-5 was the source of the residual induction of IFN-β and ISGs in mDCs. In pathogenesis studies with two unrelated positive-sense RNA viruses (West Nile virus (WNV and murine norovirus, TKO mice succumbed at rates greater than DKO mice and equal to or approaching those of mice lacking the type I IFN receptor (Ifnar(-/-. In ex vivo studies, after WNV infection or exposure to Toll-like receptor agonists, TKO mDCs failed to produce IFN-β or express ISGs. In contrast, this response was sustained in TKO macrophages following WNV infection. To define IRF-regulated gene signatures, we performed microarray analysis on WNV-infected mDC from wild type (WT, DKO, TKO, or Ifnar(-/- mice, as well as from mice lacking the RIG-I like receptor adaptor protein MAVS. Whereas the gene induction pattern in DKO mDC was similar to WT cells, remarkably, almost no ISG induction was detected in TKO or Mavs(-/- mDC. The relative equivalence of TKO and Mavs(-/- responses suggested that MAVS dominantly regulates ISG induction in mDC. Moreover, we showed that MAVS-dependent induction of ISGs can occur through an IRF-5-dependent yet IRF-3 and IRF-7-independent pathway. Our results establish IRF-3, -5, and -7 as the key transcription factors responsible for mediating the type I IFN and ISG response in mDC during WNV infection and suggest a novel signaling link between MAVS and IRF-5.

  5. Concanavalin A/IFN-gamma triggers autophagy-related necrotic hepatocyte death through IRGM1-mediated lysosomal membrane disruption.

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    Chih-Peng Chang

    Full Text Available Interferon-gamma (IFN-γ, a potent Th1 cytokine with multiple biological functions, can induce autophagy to enhance the clearance of the invading microorganism or cause cell death. We have reported that Concanavalin A (Con A can cause autophagic cell death in hepatocytes and induce both T cell-dependent and -independent acute hepatitis in immunocompetent and immunodeficient mice, respectively. Although IFN-γ is known to enhance liver injury in Con A-induced hepatitis, its role in autophagy-related hepatocyte death is not clear. In this study we report that IFN-γ can enhance Con A-induced autophagic flux and cell death in hepatoma cell lines. A necrotic cell death with increased lysosomal membrane permeabilization (LMP is observed in Con A-treated hepatoma cells in the presence of IFN-γ. Cathepsin B and L were released from lysosomes to cause cell death. Furthermore, IFN-γ induces immunity related GTPase family M member 1(IRGM1 translocation to lysosomes and prolongs its activity in Con A-treated hepatoma cells. Knockdown of IRGM1 inhibits the IFN-γ/Con A-induced LMP change and cell death. Furthermore, IFN-γ(-/- mice are resistant to Con A-induced autophagy-associated necrotic hepatocyte death. We conclude that IFN-γ enhances Con A-induced autophagic flux and causes an IRGM1-dependent lysosome-mediated necrotic cell death in hepatocytes.

  6. Control of HIV infection by IFN-α: implications for latency and a cure.

    Science.gov (United States)

    Bourke, Nollaig M; Napoletano, Silvia; Bannan, Ciaran; Ahmed, Suaad; Bergin, Colm; McKnight, Áine; Stevenson, Nigel J

    2018-03-01

    Viral infections, including HIV, trigger the production of type I interferons (IFNs), which in turn, activate a signalling cascade that ultimately culminates with the expression of anti-viral proteins. Mounting evidence suggests that type I IFNs, in particular IFN-α, play a pivotal role in limiting acute HIV infection. Highly active anti-retroviral treatment reduces viral load and increases life expectancy in HIV positive patients; however, it fails to fully eliminate latent HIV reservoirs. To revisit HIV as a curable disease, this article reviews a body of literature that highlights type I IFNs as mediators in the control of HIV infection, with particular focus on the anti-HIV restriction factors induced and/or activated by IFN-α. In addition, we discuss the relevance of type I IFN treatment in the context of HIV latency reversal, novel therapeutic intervention strategies and the potential for full HIV clearance.

  7. Type I IFN-related NETosis in ataxia telangiectasia and Artemis deficiency.

    Science.gov (United States)

    Gul, Ersin; Sayar, Esra Hazar; Gungor, Bilgi; Eroglu, Fehime Kara; Surucu, Naz; Keles, Sevgi; Guner, Sukru Nail; Findik, Siddika; Alpdundar, Esin; Ayanoglu, Ihsan Cihan; Kayaoglu, Basak; Geckin, Busra Nur; Sanli, Hatice Asena; Kahraman, Tamer; Yakicier, Cengiz; Muftuoglu, Meltem; Oguz, Berna; Cagdas Ayvaz, Deniz Nazire; Gursel, Ihsan; Ozen, Seza; Reisli, Ismail; Gursel, Mayda

    2017-11-16

    Pathological inflammatory syndromes of unknown etiology are commonly observed in ataxia telangiectasia (AT) and Artemis deficiency. Similar inflammatory manifestations also exist in patients with STING-associated vasculopathy in infancy (SAVI). We sought to test the hypothesis that the inflammation-associated manifestations observed in patients with AT and Artemis deficiency stem from increased type I IFN signature leading to neutrophil-mediated pathological damage. Cytokine/protein signatures were determined by ELISA, cytometric bead array, or quantitative PCR. Stat1 phosphorylation levels were determined by flow cytometry. DNA species accumulating in the cytosol of patients' cells were quantified microscopically and flow cytometrically. Propensity of isolated polymorhonuclear granulocytes to form neutrophil extracellular traps (NETs) was determined using fluorescence microscopy and picogreen assay. Neutrophil reactive oxygen species levels and mitochondrial stress were assayed using fluorogenic probes, microscopy, and flow cytometry. Type I and III IFN signatures were elevated in plasma and peripheral blood cells of patients with AT, Artemis deficiency, and SAVI. Chronic IFN production stemmed from the accumulation of DNA in the cytoplasm of AT and Artemis-deficient cells. Neutrophils isolated from patients spontaneously produced NETs and displayed indicators of oxidative and mitochondrial stress, supportive of their NETotic tendencies. A similar phenomenon was also observed in neutrophils from healthy controls exposed to patient plasma samples or exogeneous IFN-α. Type I IFN-mediated neutrophil activation and NET formation may contribute to inflammatory manifestations observed in patients with AT, Artemis deficiency, and SAVI. Thus, neutrophils represent a promising target to manage inflammatory syndromes in diseases with active type I IFN signature. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights

  8. Transfected poly(I:C) activates different dsRNA receptors, leading to apoptosis or immunoadjuvant response in androgen-independent prostate cancer cells.

    Science.gov (United States)

    Palchetti, Sara; Starace, Donatella; De Cesaris, Paola; Filippini, Antonio; Ziparo, Elio; Riccioli, Anna

    2015-02-27

    Despite the effectiveness of surgery or radiation therapy for the treatment of early-stage prostate cancer (PCa), there is currently no effective strategy for late-stage disease. New therapeutic targets are emerging; in particular, dsRNA receptors Toll-like receptor 3 (TLR3) and cytosolic helicases expressed by cancer cells, once activated, exert a pro-apoptotic effect in different tumors. We previously demonstrated that the synthetic analog of dsRNA poly(I:C) induces apoptosis in the androgen-dependent PCa cell line LNCaP in a TLR3-dependent fashion, whereas only a weak apoptotic effect is observed in the more aggressive and androgen-independent PCa cells PC3 and DU145. In this paper, we characterize the receptors and the signaling pathways involved in the remarkable apoptosis induced by poly(I:C) transfected by Lipofectamine (in-poly(I:C)) compared with the 12-fold higher free poly(I:C) concentration in PC3 and DU145 cells. By using genetic inhibition of different poly(I:C) receptors, we demonstrate the crucial role of TLR3 and Src in in-poly(I:C)-induced apoptosis. Therefore, we show that the increased in-poly(I:C) apoptotic efficacy is due to a higher binding of endosomal TLR3. On the other hand, we show that in-poly(I:C) binding to cytosolic receptors MDA5 and RIG-I triggers IRF3-mediated signaling, leading uniquely to the up-regulation of IFN-β, which likely in turn induces increased TLR3, MDA5, and RIG-I proteins. In summary, in-poly(I:C) activates two distinct antitumor pathways in PC3 and DU145 cells: one mediated by the TLR3/Src/STAT1 axis, leading to apoptosis, and the other one mediated by MDA5/RIG-I/IRF3, leading to immunoadjuvant IFN-β expression. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. The murine cytomegalovirus M35 protein antagonizes type I IFN induction downstream of pattern recognition receptors by targeting NF-κB mediated transcription.

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    Baca Chan

    2017-05-01

    Full Text Available The type I interferon (IFN response is imperative for the establishment of the early antiviral immune response. Here we report the identification of the first type I IFN antagonist encoded by murine cytomegalovirus (MCMV that shuts down signaling following pattern recognition receptor (PRR sensing. Screening of an MCMV open reading frame (ORF library identified M35 as a novel and strong negative modulator of IFNβ promoter induction following activation of both RNA and DNA cytoplasmic PRR. Additionally, M35 inhibits the proinflammatory cytokine response downstream of Toll-like receptors (TLR. Using a series of luciferase-based reporters with specific transcription factor binding sites, we determined that M35 targets NF-κB-, but not IRF-mediated, transcription. Expression of M35 upon retroviral transduction of immortalized bone marrow-derived macrophages (iBMDM led to reduced IFNβ transcription and secretion upon activation of stimulator of IFN genes (STING-dependent signaling. On the other hand, M35 does not antagonize interferon-stimulated gene (ISG 56 promoter induction or ISG transcription upon exogenous stimulation of the type I IFN receptor (IFNAR. M35 is present in the viral particle and, upon MCMV infection of fibroblasts, is immediately shuttled to the nucleus where it exerts its immunomodulatory effects. Deletion of M35 from the MCMV genome and hence from the viral particle resulted in elevated type I IFN transcription and secretion in vitro and in vivo. In the absence of M35, lower viral titers are observed during acute infection of the host, and productive infection in the salivary glands was not detected. In conclusion, the M35 protein is released by MCMV immediately upon infection in order to deftly inhibit the antiviral type I IFN response by targeting NF-κB-mediated transcription. The identification of this novel viral protein reinforces the importance of timely countermeasures in the complex relationship between virus and host.

  10. Calcium/Calmodulin-Dependent Protein Kinase IV Mediates IFN-γ-Induced Immune Behaviors in Skeletal Muscle Cells

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    RuiCai Gu

    2018-03-01

    Full Text Available Background/Aims: Whether calcium/calmodulin-dependent protein kinase IV (CaMKIV plays a role in regulating immunologic features of muscle cells in inflammatory environment, as it does for immune cells, remains mostly unknown. In this study, we investigated the influence of endogenous CaMKIV on the immunological characteristics of myoblasts and myotubes received IFN-γ stimulation. Methods: C2C12 and murine myogenic precursor cells (MPCs were cultured and differentiated in vitro, in the presence of pro-inflammatory IFN-γ. CaMKIV shRNA lentivirus transfection was performed to knockdown CaMKIV gene in C2C12 cells. pEGFP-N1-CaMKIV plasmid was delivered into knockout cells for recovering intracellular CaMKIV gene level. CREB1 antagonist KG-501 was used to block CREB signal. qPCR, immunoblot analysis, or immunofluorescence was used to detect mRNA and protein levels of CaMKIV, immuno-molecules, or pro-inflammatory cytokines and chemokines. Co-stimulatory molecules expression was assessed by FACS analysis. Results: IFN-γ induces the expression or up-regulation of MHC-I/II and TLR3, and the up-regulation of CaMKIV level in muscle cells. In contrast, CaMKIV knockdown in myoblasts and myotubes leads to expression inhibition of the above immuno-molecules. As well, CaMKIV knockdown selectively inhibits pro-inflammatory cytokines/chemokines, and co-stimulatory molecules expression in IFN-γ treated myoblasts and myotubes. Finally, CaMKIV knockdown abolishes IFN-γ induced CREB pathway molecules accumulation in differentiated myotubes. Conclusions: CaMKIV can be induced to up-regulate in muscle cells under inflammatory condition, and positively mediates intrinsic immune behaviors of muscle cells triggered by IFN-γ.

  11. RIG-I Like Receptors in Antiviral Immunity and Therapeutic Applications

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    Michael Gale Jr.

    2011-06-01

    Full Text Available The RNA helicase family of RIG-I-like receptors (RLRs is a key component of host defense mechanisms responsible for detecting viruses and triggering innate immune signaling cascades to control viral replication and dissemination. As cytoplasm-based sensors, RLRs recognize foreign RNA in the cell and activate a cascade of antiviral responses including the induction of type I interferons, inflammasome activation, and expression of proinflammatory cytokines and chemokines. This review provides a brief overview of RLR function, ligand interactions, and downstream signaling events with an expanded discussion on the therapeutic potential of targeting RLRs for immune stimulation and treatment of virus infection.

  12. Cyclic GMP-AMP Synthase Is the Cytosolic Sensor of Plasmodium falciparum Genomic DNA and Activates Type I IFN in Malaria.

    Science.gov (United States)

    Gallego-Marin, Carolina; Schrum, Jacob E; Andrade, Warrison A; Shaffer, Scott A; Giraldo, Lina F; Lasso, Alvaro M; Kurt-Jones, Evelyn A; Fitzgerald, Katherine A; Golenbock, Douglas T

    2018-01-15

    Innate immune receptors have a key role in the sensing of malaria and initiating immune responses. As a consequence of infection, systemic inflammation emerges and is directly related to signs and symptoms during acute disease. We have previously reported that plasmodial DNA is the primary driver of systemic inflammation in malaria, both within the phagolysosome and in the cytosol of effector cells. In this article, we demonstrate that Plasmodium falciparum genomic DNA delivered to the cytosol of human monocytes binds and activates cyclic GMP-AMP synthase (cGAS). Activated cGAS synthesizes 2'3'-cGAMP, which we subsequently can detect using liquid chromatography-tandem mass spectrometry. 2'3'-cGAMP acts as a second messenger for STING activation and triggers TBK1/IRF3 activation, resulting in type I IFN production in human cells. This induction of type I IFN was independent of IFI16. Access of DNA to the cytosolic compartment is mediated by hemozoin, because incubation of purified malaria pigment with DNase abrogated IFN-β induction. Collectively, these observations implicate cGAS as an important cytosolic sensor of P. falciparum genomic DNA and reveal the role of the cGAS/STING pathway in the induction of type I IFN in response to malaria parasites. Copyright © 2018 by The American Association of Immunologists, Inc.

  13. Nuclear export signal of PRRSV NSP1α is necessary for type I IFN inhibition

    International Nuclear Information System (INIS)

    Chen, Zhi; Liu, Shaoning; Sun, Wenbo; Chen, Lei; Yoo, Dongwan; Li, Feng; Ren, Sufang; Guo, Lihui; Cong, Xiaoyan; Li, Jun; Zhou, Shun; Wu, Jiaqiang

    2016-01-01

    The nonstructural protein 1α (NSP1α) of porcine reproductive and respiratory syndrome virus (PRRSV) is a nucleo-cytoplasmic protein that suppresses the production of type I interferon (IFN). In this study, we investigated the relationship between the subcellular distribution of NSP1α and its inhibition of type I IFN. NSP1α was found to contain the classical nuclear export signal (NES) and NSP1α nuclear export was CRM-1-mediated. NSP1α was shuttling between the nucleus and cytoplasm. We also showed that the nuclear export of NSP1α was necessary for its ability for type I IFN inhibition. NSP1α was also found to interact with CBP, which implies a possible mechanism of CBP degradation by NSP1α. Taken together, our results describe a novel mechanism of PRRSV NSP1α for type I IFN inhibition and suppression of the host innate antiviral response. - Highlights: •NSP1α contains the NES and NSP1α nuclear export was CRM-1-mediated. •NSP1α was shuttling between the nucleus and cytoplasm continuously. •The nuclear export of NSP1α was necessary for its ability for type I IFN inhibition. •NSP1α interacts with CBP, which implies the mechanism of CBP degradation by NSP1α.

  14. Nuclear export signal of PRRSV NSP1α is necessary for type I IFN inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhi [Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Sangyuan Road No. 8, Jinan 250100 (China); Liu, Shaoning [Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Sangyuan Road No. 8, Jinan 250100 (China); Shandong Institute of Veterinary Drug Quality Inspection, Shandong Key Laboratory for Quality Safety Monitoring and Risk Assessment of Animal Products, Huaicun Street No. 68, Jinan 250722, Shandong Province (China); Sun, Wenbo; Chen, Lei [Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Sangyuan Road No. 8, Jinan 250100 (China); Yoo, Dongwan [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Ave, Urbana, IL 61802 (United States); Li, Feng [Department of Biology and Microbiology, Department of Veterinary and Biomedical Sciences, South Dakota State University, Brookings, SD 57007 (United States); Ren, Sufang; Guo, Lihui; Cong, Xiaoyan; Li, Jun [Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Sangyuan Road No. 8, Jinan 250100 (China); Zhou, Shun [College of marine science and engineering, Qingdao Agricultural University, Changcheng Road No. 700, Qingdao 266109 (China); Wu, Jiaqiang, E-mail: wujiaqiang2000@sina.com [Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Sangyuan Road No. 8, Jinan 250100 (China); and others

    2016-12-15

    The nonstructural protein 1α (NSP1α) of porcine reproductive and respiratory syndrome virus (PRRSV) is a nucleo-cytoplasmic protein that suppresses the production of type I interferon (IFN). In this study, we investigated the relationship between the subcellular distribution of NSP1α and its inhibition of type I IFN. NSP1α was found to contain the classical nuclear export signal (NES) and NSP1α nuclear export was CRM-1-mediated. NSP1α was shuttling between the nucleus and cytoplasm. We also showed that the nuclear export of NSP1α was necessary for its ability for type I IFN inhibition. NSP1α was also found to interact with CBP, which implies a possible mechanism of CBP degradation by NSP1α. Taken together, our results describe a novel mechanism of PRRSV NSP1α for type I IFN inhibition and suppression of the host innate antiviral response. - Highlights: •NSP1α contains the NES and NSP1α nuclear export was CRM-1-mediated. •NSP1α was shuttling between the nucleus and cytoplasm continuously. •The nuclear export of NSP1α was necessary for its ability for type I IFN inhibition. •NSP1α interacts with CBP, which implies the mechanism of CBP degradation by NSP1α.

  15. Expression of an IRF-3 fusion protein and mouse estrogen receptor, inhibits hepatitis C viral replication in RIG-I-deficient Huh 7.5 cells

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    Liu Chen

    2011-09-01

    Full Text Available Abstract Interferon Regulatory Factor-3 (IRF-3 plays a central role in the induction of interferon (IFN production and succeeding interferon-stimulated genes (ISG expression en route for restraining hepatitis C virus (HCV infection. Here, we established a stable Huh7.5-IRF3ER cell line expressing a fusion protein of IRF-3 and mouse estrogen receptor (ER to examine IFN production and anti-HCV effects of IRF-3 in retinoic acid inducible-gene-I (RIG-I deficient Huh 7.5 cells. Homodimerization of the IRF-3ER fusion protein was detected by Western blotting after treatment with the estrogen receptor agonist 4-hydrotamoxifen (4-HT in Huh7.5-IRF3ER cells. Expression of IFN-α, IFN-β, and their inhibitory effects on HCV replication were demonstrated by real-time polymerase chain reaction (PCR. Peak expression of IFN-α and IFN-β was achieved 24-hours post 4-HT treatment, coinciding with the appearance of phosphorylated signal transducer and activator of transcription (STAT proteins. Additionally, HCV viral replication declined in time-dependent fashion. In previous studies, a novel IFN-mediated pathway regulating expression of 1-8U and heterogeneous nuclear ribonucleoprotein M (hnRNP M inhibited HCV internal ribosomal entry site (IRES-dependent translation. When expression of ISGs such as 1-8U and hnRNP M were measured in 4-HT-treated Huh7.5-IRF3ER cells, both genes were positively regulated by activation of the IRF-3ER fusion protein. In conclusion, the anti-HCV effects of IRF-3ER homodimerization inhibited HCV RNA replication as well as HCV IRES-dependent translation in Huh7.5-IRF3ER cells. The results of this study indicate that IRF-3ER homodimerization is a key step to restore IFN expression in Huh7.5-IRF3ER cells and in achieving its anti-HCV effects.

  16. The combination of IL-21 and IFN-alpha boosts STAT3 activation, cytotoxicity and experimental tumor therapy

    DEFF Research Database (Denmark)

    Eriksen, Karsten W; Søndergaard, Henrik; Woetmann, Anders

    2008-01-01

    such as IFN-alpha and IL-2 have multiple and severe side effects. Accordingly, they are generally used at sub-optimal doses, which limit their clinical efficacy. Here we hypothesized that a combination of IFN-alpha and IL-21, a novel cytokine of the IL-2 family with anti-cancer effects, will increase the anti......-cancer efficacy at sub-optimal cytokine doses. We show that the combined stimulation of target-cells with IFN-alpha and IL-21 triggers an increased STAT3 activation whereas the activation of other STATs including STAT1/2 is unaffected. In parallel, the combined stimulation with IFN-alpha and IL-21 triggers...... a selective increase in MHC class I expression and NK- and CD8(+) T-cell-mediated cytotoxicity. In an experimental in vivo model of renal carcinoma, the combined treatment of IFN-alpha and IL-21 also produces a significant anti-cancer effect as judged by an inhibition of tumor growth and an increased survival...

  17. CYLD Proteolysis Protects Macrophages from TNF-Mediated Auto-necroptosis Induced by LPS and Licensed by Type I IFN

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    Diana Legarda

    2016-06-01

    Full Text Available Tumor necrosis factor (TNF induces necroptosis, a RIPK3/MLKL-dependent form of inflammatory cell death. In response to infection by Gram-negative bacteria, multiple receptors on macrophages, including TLR4, TNF, and type I IFN receptors, are concurrently activated, but it is unclear how they crosstalk to regulate necroptosis. We report that TLR4 activates CASPASE-8 to cleave and remove the deubiquitinase cylindromatosis (CYLD in a TRIF- and RIPK1-dependent manner to disable necroptosis in macrophages. Inhibiting CASPASE-8 leads to CYLD-dependent necroptosis caused by the TNF produced in response to TLR4 ligation. While lipopolysaccharides (LPS-induced necroptosis was abrogated in Tnf−/− macrophages, a soluble TNF antagonist was not able to do so in Tnf+/+ macrophages, indicating that necroptosis occurs in a cell-autonomous manner. Surprisingly, TNF-mediated auto-necroptosis of macrophages requires type I IFN, which primes the expression of key necroptosis-signaling molecules, including TNFR2 and MLKL. Thus, the TNF necroptosis pathway is regulated by both negative and positive crosstalk.

  18. NOD1 contributes to mouse host defense against Helicobacter pylori via induction of type I IFN and activation of the ISGF3 signaling pathway

    Science.gov (United States)

    Watanabe, Tomohiro; Asano, Naoki; Fichtner-Feigl, Stefan; Gorelick, Peter L.; Tsuji, Yoshihisa; Matsumoto, Yuko; Chiba, Tsutomu; Fuss, Ivan J.; Kitani, Atsushi; Strober, Warren

    2010-01-01

    Nucleotide-binding oligomerization domain 1 (NOD1) is an intracellular epithelial cell protein known to play a role in host defense at mucosal surfaces. Here we show that a ligand specific for NOD1, a peptide derived from peptidoglycan, initiates an unexpected signaling pathway in human epithelial cell lines that results in the production of type I IFN. Detailed analysis revealed the components of the signaling pathway. NOD1 binding to its ligand triggered activation of the serine-threonine kinase RICK, which was then able to bind TNF receptor–associated factor 3 (TRAF3). This in turn led to activation of TANK-binding kinase 1 (TBK1) and IκB kinase ε (IKKε) and the subsequent activation of IFN regulatory factor 7 (IRF7). IRF7 induced IFN-β production, which led to activation of a heterotrimeric transcription factor complex known as IFN-stimulated gene factor 3 (ISGF3) and the subsequent production of CXCL10 and additional type I IFN. In vivo studies showed that mice lacking the receptor for IFN-β or subjected to gene silencing of the ISGF3 component Stat1 exhibited decreased CXCL10 responses and increased susceptibility to Helicobacter pylori infection, phenotypes observed in NOD1-deficient mice. These studies thus establish that NOD1 can activate the ISGF3 signaling pathway that is usually associated with protection against viral infection to provide mice with robust type I IFN–mediated protection from H. pylori and possibly other mucosal infections. PMID:20389019

  19. Injury-Induced Type I IFN Signaling Regulates Inflammatory Responses in the Central Nervous System

    DEFF Research Database (Denmark)

    Khorooshi, Reza; Owens, Trevor

    2010-01-01

    Innate glial response is critical for the induction of inflammatory mediators and recruitment of leukocytes to sites of the injury in the CNS. We have examined the involvement of type I IFN signaling in the mouse hippocampus following sterile injury (transection of entorhinal afferents). Type I I...

  20. The autoinhibitory CARD2-Hel2i Interface of RIG-I governs RNA selection.

    Science.gov (United States)

    Ramanathan, Anand; Devarkar, Swapnil C; Jiang, Fuguo; Miller, Matthew T; Khan, Abdul G; Marcotrigiano, Joseph; Patel, Smita S

    2016-01-29

    RIG-I (Retinoic Acid Inducible Gene-I) is a cytosolic innate immune receptor that detects atypical features in viral RNAs as foreign to initiate a Type I interferon signaling response. RIG-I is present in an autoinhibited state in the cytoplasm and activated by blunt-ended double-stranded (ds)RNAs carrying a 5' triphosphate (ppp) moiety. These features found in many pathogenic RNAs are absent in cellular RNAs due to post-transcriptional modifications of RNA ends. Although RIG-I is structurally well characterized, the mechanistic basis for RIG-I's remarkable ability to discriminate between cellular and pathogenic RNAs is not completely understood. We show that RIG-I's selectivity for blunt-ended 5'-ppp dsRNAs is ≈3000 times higher than non-blunt ended dsRNAs commonly found in cellular RNAs. Discrimination occurs at multiple stages and signaling RNAs have high affinity and ATPase turnover rate and thus a high katpase/Kd. We show that RIG-I uses its autoinhibitory CARD2-Hel2i (second CARD-helicase insertion domain) interface as a barrier to select against non-blunt ended dsRNAs. Accordingly, deletion of CARDs or point mutations in the CARD2-Hel2i interface decreases the selectivity from ≈3000 to 150 and 750, respectively. We propose that the CARD2-Hel2i interface is a 'gate' that prevents cellular RNAs from generating productive complexes that can signal. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  1. Immune cell-poor melanomas benefit from PD-1 blockade after targeted type I IFN activation.

    Science.gov (United States)

    Bald, Tobias; Landsberg, Jennifer; Lopez-Ramos, Dorys; Renn, Marcel; Glodde, Nicole; Jansen, Philipp; Gaffal, Evelyn; Steitz, Julia; Tolba, Rene; Kalinke, Ulrich; Limmer, Andreas; Jönsson, Göran; Hölzel, Michael; Tüting, Thomas

    2014-06-01

    Infiltration of human melanomas with cytotoxic immune cells correlates with spontaneous type I IFN activation and a favorable prognosis. Therapeutic blockade of immune-inhibitory receptors in patients with preexisting lymphocytic infiltrates prolongs survival, but new complementary strategies are needed to activate cellular antitumor immunity in immune cell-poor melanomas. Here, we show that primary melanomas in Hgf-Cdk4(R24C) mice, which imitate human immune cell-poor melanomas with a poor outcome, escape IFN-induced immune surveillance and editing. Peritumoral injections of immunostimulatory RNA initiated a cytotoxic inflammatory response in the tumor microenvironment and significantly impaired tumor growth. This critically required the coordinated induction of type I IFN responses by dendritic, myeloid, natural killer, and T cells. Importantly, antibody-mediated blockade of the IFN-induced immune-inhibitory interaction between PD-L1 and PD-1 receptors further prolonged the survival. These results highlight important interconnections between type I IFNs and immune-inhibitory receptors in melanoma pathogenesis, which serve as targets for combination immunotherapies. Using a genetically engineered mouse melanoma model, we demonstrate that targeted activation of the type I IFN system with immunostimulatory RNA in combination with blockade of immune-inhibitory receptors is a rational strategy to expose immune cell-poor tumors to cellular immune surveillance. ©2014 American Association for Cancer Research.

  2. Kobuvirus VP3 protein restricts the IFN-β-triggered signaling pathway by inhibiting STAT2-IRF9 and STAT2-STAT2 complex formation

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Qianqian; Lan, Xi; Wang, Chen [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046 (China); Ren, Yujie; Yue, Ningning [College of Life Sciences, Wuhan University, Wuhan 430072 (China); Wang, Junyong [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046 (China); Zhong, Bo [College of Life Sciences, Wuhan University, Wuhan 430072 (China); Medical Research Institute, School of Medicine, Wuhan University, Wuhan 430071 (China); Zhu, Qiyun, E-mail: zhuqiyun@caas.cn [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046 (China)

    2017-07-15

    Emerged porcine kobuvirus (PKV) has adversely affected the global swine industry since 2008, but the etiological biology of PKV is unclear. Screening PKV-encoded structural and non-structural proteins with a type I IFN-responsive luciferase reporter showed that PKV VP3 protein inhibited the IFN-β-triggered signaling pathway, resulting in the decrease of VSV-GFP replication. QPCR data showed that IFN-β downstream cytokine genes were suppressed without cell-type specificity as well. The results from biochemical experiments indicated that PKV VP3 associated with STAT2 and IRF9, and interfered with the formation of the STAT2-IRF9 and STAT2-STAT2 complex, impairing nuclear translocation of STAT2 and IRF9. Taken together, these data reveal a new mechanism for immune evasion of PKV. - Highlights: •PKV VP3 inhibits the IFN-β-triggered signaling pathway. •VP3 associates with STAT2 and IRF9. •VP3 blocks the STAT2-IRF9 nuclear translocation. •VP3 utilizes a novel strategy for innate immune evasion.

  3. Role of the RIG-I-like receptors in antiviral response

    Directory of Open Access Journals (Sweden)

    Agnieszka Jabłońska

    2014-01-01

    Full Text Available The innate nonspecific immunity is the first line of defense against viral infection. Toll-like receptors (TLRs and retinoic acid-inducible gene I (RIG-I-like receptors (RLRs are two main receptor families detecting viral nucleic acid. So far, three RLR family members were characterized: RIG-I, MDA5 and LGP2. RLR constitute a family of cytoplasmic helicases, which recognized intracellular single-stranded and double-stranded RNA that is introduced to cytosol during viral infection and replication. In this work we review the current knowledge about the mechanisms of viral recognition by RIG-I-like receptors and their signaling pathways for the activation of type I interferons and pro-inflammatory cytokines synthesis.

  4. Compromised virus control and augmented perforin-mediated immunopathology in IFN-gamma-deficient mice infected with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Nansen, A; Jensen, Teis; Christensen, Jan Pravsgaard

    1999-01-01

    To define the role of IFN-gamma in the control of acute infection with a noncytopathogenic virus, mice with targeted defects of the genes encoding IFN-gamma, perforin, or both were infected i.v. with two strains of lymphocytic choriomeningitis virus differing markedly in their capacity to spread...... in wild-type mice. Our results reveal that IFN-gamma is pivotal to T cell-mediated control of a rapidly invasive stain, whereas it is less important in the acute elimination of a slowly invasive strain. Moreover, the majority of mice infected with the rapidly invasive strain succumb to a wasting syndrome...... mediated by CD8+ effector cells. The primary effector mechanism underlying this disease is perforin-dependent lysis, but other mechanisms are also involved. Wasting disease can be prevented if naive CD8+ cells from mice transgenic for an MHC class I-restricted lymphocytic choriomeningitis virus...

  5. Reprogramming of murine macrophages through TLR2 confers viral resistance via TRAF3-mediated, enhanced interferon production.

    Directory of Open Access Journals (Sweden)

    Darren J Perkins

    Full Text Available The cell surface/endosomal Toll-like Receptors (TLRs are instrumental in initiating immune responses to both bacteria and viruses. With the exception of TLR2, all TLRs and cytosolic RIG-I-like receptors (RLRs with known virus-derived ligands induce type I interferons (IFNs in macrophages or dendritic cells. Herein, we report that prior ligation of TLR2, an event previously shown to induce "homo" or "hetero" tolerance, strongly "primes" macrophages for increased Type I IFN production in response to subsequent TLR/RLR signaling. This occurs by increasing activation of the transcription factor, IFN Regulatory Factor-3 (IRF-3 that, in turn, leads to enhanced induction of IFN-β, while expression of other pro-inflammatory genes are suppressed (tolerized. In vitro or in vivo "priming" of murine macrophages with TLR2 ligands increase virus-mediated IFN induction and resistance to infection. This priming effect of TLR2 is mediated by the selective upregulation of the K63 ubiquitin ligase, TRAF3. Thus, we provide a mechanistic explanation for the observed antiviral actions of MyD88-dependent TLR2 and further define the role of TRAF3 in viral innate immunity.

  6. HACE1 Negatively Regulates Virus-Triggered Type I IFN Signaling by Impeding the Formation of the MAVS-TRAF3 Complex

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    He-Ting Mao

    2016-05-01

    Full Text Available During virus infection, the cascade signaling pathway that leads to the production of proinflammatory cytokines is controlled at multiple levels to avoid detrimental overreaction. HACE1 has been characterized as an important tumor suppressor. Here, we identified HACE1 as an important negative regulator of virus-triggered type I IFN signaling. Overexpression of HACE1 inhibited Sendai virus- or poly (I:C-induced signaling and resulted in reduced IFNB1 production and enhanced virus replication. Knockdown of HACE1 expression exhibited the opposite effects. Ubiquitin E3 ligase activity of the dead mutant HACE1/C876A had a comparable inhibitory function as WT HACE1, suggesting that the suppressive function of HACE1 on virus-induced signaling is independent of its E3 ligase activity. Further study indicated that HACE1 acted downstream of MAVS and upstream of TBK1. Mechanistic studies showed that HACE1 exerts its inhibitory role on virus-induced signaling by disrupting the MAVS-TRAF3 complex. Therefore, we uncovered a novel function of HACE1 in innate immunity regulation.

  7. Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways.

    Directory of Open Access Journals (Sweden)

    Young Woo Han

    2014-09-01

    Full Text Available Japanese encephalitis (JE is major emerging neurologic disease caused by JE virus. To date, the impact of TLR molecules on JE progression has not been addressed. Here, we determined whether each TLR modulates JE, using several TLR-deficient mouse strains (TLR2, TLR3, TLR4, TLR7, TLR9. Surprisingly, among the tested TLR-deficient mice there were contrasting results in TLR3(-/- and TLR4(-/- mice, i.e. TLR3(-/- mice were highly susceptible to JE, whereas TLR4(-/- mice showed enhanced resistance to JE. TLR3 ablation induced severe CNS inflammation characterized by early infiltration of inflammatory CD11b(+Ly-6Chigh monocytes along with profoundly increased viral burden, proinflammatory cytokine/chemokine expression as well as BBB permeability. In contrast, TLR4(-/- mice showed mild CNS inflammation manifested by reduced viral burden, leukocyte infiltration and proinflammatory cytokine expression. Interestingly, TLR4 ablation provided potent in vivo systemic type I IFN innate response, as well as ex vivo type I IFN production associated with strong induction of antiviral PRRs (RIG-I, MDA5, transcription factors (IRF-3, IRF-7, and IFN-dependent (PKR, Oas1, Mx and independent ISGs (ISG49, ISG54, ISG56 by alternative activation of IRF3 and NF-κB in myeloid-derived DCs and macrophages, as compared to TLR3(-/- myeloid-derived cells which were more permissive to viral replication through impaired type I IFN innate response. TLR4 ablation also appeared to mount an enhanced type I IFN innate and humoral, CD4(+ and CD8(+ T cell responses, which were mediated by altered immune cell populations (increased number of plasmacytoid DCs and NK cells, reduced CD11b(+Ly-6C(high monocytes and CD4(+Foxp3(+ Treg number in lymphoid tissue. Thus, potent type I IFN innate and adaptive immune responses in the absence of TLR4 were closely coupled with reduced JE lethality. Collectively, these results suggest that a balanced triggering of TLR signal array by viral components

  8. Cellular sources and targets of IFN-γ-mediated protection against viral demyelination and neurological deficits

    Science.gov (United States)

    Murray, Paul D.; McGavern, Dorian B.; Pease, Larry R.; Rodriguez, Moses

    2017-01-01

    IFN-γ is an anti-viral and immunomodulatory cytokine critical for resistance to multiple pathogens. Using mice with targeted disruption of the gene for IFN-γ, we previously demonstrated that this cytokine is critical for resistance to viral persistence and demyelination in the Theiler’s virus model of multiple sclerosis. During viral infections, IFN-γ is produced by natural killer (NK) cells, CD4+ and CD8+ T cells; however, the proportions of lymphocyte subsets responding to virus infection influences the contributions to IFN-γ-mediated protection. To determine the lymphocyte subsets that produce IFN-γ to maintain resistance, we used adoptive transfer strategies to generate mice with lymphocyte-specific deficiencies in IFN-γ-production. We demonstrate that IFN-γ production by both CD4+ and CD8+ T cell subsets is critical for resistance to Theiler’s murine encephalomyelitis virus (TMEV)-induced demyelination and neurological disease, and that CD4+ T cells make a greater contribution to IFN-γ-mediated protection. To determine the cellular targets of IFN-γ-mediated responses, we used adoptive transfer studies and bone marrow chimerism to generate mice in which either hematopoietic or somatic cells lacked the ability to express IFN-γ receptor. We demonstrate that IFN-γ receptor must be present on central nervous system glia, but not bone marrow-derived lymphocytes, in order to maintain resistance to TMEV-induced demyelination. PMID:11857334

  9. DMPD: MDA5/RIG-I and virus recognition. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18272355 MDA5/RIG-I and virus recognition. Takeuchi O, Akira S. Curr Opin Immunol. ...2008 Feb;20(1):17-22. Epub 2008 Feb 12. (.png) (.svg) (.html) (.csml) Show MDA5/RIG-I and virus recognition.... PubmedID 18272355 Title MDA5/RIG-I and virus recognition. Authors Takeuchi O, Akira S. Publication Curr Opi

  10. MyD88 and STING signaling pathways are required for IRF3-mediated IFN-β induction in response to Brucella abortus infection.

    Directory of Open Access Journals (Sweden)

    Leonardo A de Almeida

    Full Text Available Type I interferons (IFNs are cytokines that orchestrate diverse immune responses to viral and bacterial infections. Although typically considered to be most important molecules in response to viruses, type I IFNs are also induced by most, if not all, bacterial pathogens. In this study, we addressed the role of type I IFN signaling during Brucella abortus infection, a facultative intracellular bacterial pathogen that causes abortion in domestic animals and undulant fever in humans. Herein, we have shown that B. abortus induced IFN-β in macrophages and splenocytes. Further, IFN-β induction by Brucella was mediated by IRF3 signaling pathway and activates IFN-stimulated genes via STAT1 phosphorylation. In addition, IFN-β expression induced by Brucella is independent of TLRs and TRIF signaling but MyD88-dependent, a pathway not yet described for Gram-negative bacteria. Furthermore, we have identified Brucella DNA as the major bacterial component to induce IFN-β and our study revealed that this molecule operates through a mechanism dependent on RNA polymerase III to be sensed probably by an unknown receptor via the adaptor molecule STING. Finally, we have demonstrated that IFN-αβR KO mice are more resistant to infection suggesting that type I IFN signaling is detrimental to host control of Brucella. This resistance phenotype is accompanied by increased IFN-γ and NO production by IFN-αβR KO spleen cells and reduced apoptosis.

  11. MyD88 and STING Signaling Pathways Are Required for IRF3-Mediated IFN-β Induction in Response to Brucella abortus Infection

    Science.gov (United States)

    de Almeida, Leonardo A.; Carvalho, Natalia B.; Oliveira, Fernanda S.; Lacerda, Thais L. S.; Vasconcelos, Anilton C.; Nogueira, Lucas; Bafica, Andre; Silva, Aristóbolo M.; Oliveira, Sergio C.

    2011-01-01

    Type I interferons (IFNs) are cytokines that orchestrate diverse immune responses to viral and bacterial infections. Although typically considered to be most important molecules in response to viruses, type I IFNs are also induced by most, if not all, bacterial pathogens. In this study, we addressed the role of type I IFN signaling during Brucella abortus infection, a facultative intracellular bacterial pathogen that causes abortion in domestic animals and undulant fever in humans. Herein, we have shown that B. abortus induced IFN-β in macrophages and splenocytes. Further, IFN-β induction by Brucella was mediated by IRF3 signaling pathway and activates IFN-stimulated genes via STAT1 phosphorylation. In addition, IFN-β expression induced by Brucella is independent of TLRs and TRIF signaling but MyD88-dependent, a pathway not yet described for Gram-negative bacteria. Furthermore, we have identified Brucella DNA as the major bacterial component to induce IFN-β and our study revealed that this molecule operates through a mechanism dependent on RNA polymerase III to be sensed probably by an unknown receptor via the adaptor molecule STING. Finally, we have demonstrated that IFN-αβR KO mice are more resistant to infection suggesting that type I IFN signaling is detrimental to host control of Brucella. This resistance phenotype is accompanied by increased IFN-γ and NO production by IFN-αβR KO spleen cells and reduced apoptosis. PMID:21829705

  12. Cell-specific type I IFN signatures in autoimmunity and viral infection: what makes the difference?

    Directory of Open Access Journals (Sweden)

    Chieko Kyogoku

    Full Text Available Gene expression profiling of peripheral blood mononuclear cells (PBMCs has revealed a crucial role for type I interferon (IFN in the pathogenesis of systemic lupus erythematosus (SLE. However, it is unclear how particular leucocyte subsets contribute to the overall type I IFN signature of PBMCs and whole blood samples.Furthermore, a detailed analysis describing the differences in the IFN signature in autoimmune diseases from that observed after viral infection has not been performed to date. Therefore, in this study, the transcriptional responses in peripheral T helper cells (CD4(+ and monocyte subsets (CD16(- inflammatory and CD16(+ resident monocytes isolated from patients with SLE, healthy donors (ND immunised with the yellow fever vaccine YFV-17Dand untreated controls were compared by global gene expression profiling.It was striking that all of the transcripts that were regulated in response to viral exposure were also found to be differentially regulated in SLE, albeit with markedly lower fold-change values. In addition to this common IFN signature, a pathogenic IFN-associated gene signature was detected in the CD4(+ T cells and monocytes from the lupus patients. IL-10, IL-9 and IL-15-mediated JAK/STAT signalling was shown to be involved in the pathological amplification of IFN responses observed in SLE. Type I IFN signatures identified were successfully applied for the monitoring of interferon responses in PBMCs of an independent cohort of SLE patients and virus-infected individuals. Moreover, these cell-type specific gene signatures allowed a correct classification of PBMCs independent from their heterogenic cellular composition. In conclusion, our data show for the first time that monocytes and CD4 cells are sensitive biosensors to monitor type I interferon response signatures in autoimmunity and viral infection and how these transriptional responses are modulated in a cell- and disease-specific manner.

  13. The IFN Response in Bats Displays Distinctive IFN-Stimulated Gene Expression Kinetics with Atypical RNASEL Induction.

    Science.gov (United States)

    De La Cruz-Rivera, Pamela C; Kanchwala, Mohammed; Liang, Hanquan; Kumar, Ashwani; Wang, Lin-Fa; Xing, Chao; Schoggins, John W

    2018-01-01

    Bats host a large number of zoonotic viruses, including several viruses that are highly pathogenic to other mammals. The mechanisms underlying this rich viral diversity are unknown, but they may be linked to unique immunological features that allow bats to act as asymptomatic viral reservoirs. Vertebrates respond to viral infection by inducing IFNs, which trigger antiviral defenses through IFN-stimulated gene (ISG) expression. Although the IFN system of several bats is characterized at the genomic level, less is known about bat IFN-mediated transcriptional responses. In this article, we show that IFN signaling in bat cells from the black flying fox ( Pteropus alecto ) consists of conserved and unique ISG expression profiles. In IFN-stimulated cells, bat ISGs comprise two unique temporal subclusters with similar early induction kinetics but distinct late-phase declines. In contrast, human ISGs lack this decline phase and remained elevated for longer periods. Notably, in unstimulated cells, bat ISGs were expressed more highly than their human counterparts. We also found that the antiviral effector 2-5A-dependent endoribonuclease, which is not an ISG in humans, is highly IFN inducible in black flying fox cells and contributes to cell-intrinsic control of viral infection. These studies reveal distinctive innate immune features that may underlie a unique virus-host relationship in bats. Copyright © 2017 by The American Association of Immunologists, Inc.

  14. IFN-γ protects from lethal IL-17 mediated viral encephalomyelitis independent of neutrophils

    Directory of Open Access Journals (Sweden)

    Savarin Carine

    2012-05-01

    Full Text Available Abstract Background The interplay between IFN-γ, IL-17 and neutrophils during CNS inflammatory disease is complex due to cross-regulatory factors affecting both positive and negative feedback loops. These interactions have hindered the ability to distinguish the relative contributions of neutrophils, Th1 and Th17 cell-derived effector molecules from secondary mediators to tissue damage and morbidity. Methods Encephalitis induced by a gliatropic murine coronavirus was used as a model to assess the direct contributions of neutrophils, IFN-γ and IL-17 to virus-induced mortality. CNS inflammatory conditions were selectively manipulated by adoptive transfer of virus-primed wild-type (WT or IFN-γ deficient (GKO memory CD4+ T cells into infected SCID mice, coupled with antibody-mediated neutrophil depletion and cytokine blockade. Results Transfer of GKO memory CD4+ T cells into infected SCID mice induced rapid mortality compared to recipients of WT memory CD4+ T cells, despite similar virus control and demyelination. In contrast to recipients of WT CD4+ T cells, extensive neutrophil infiltration and IL-17 expression within the CNS in recipients of GKO CD4+ T cells provided a model to directly assess their contribution(s to disease. Recipients of WT CD4+ T cells depleted of IFN-γ did not express IL-17 and were spared from mortality despite abundant CNS neutrophil infiltration, indicating that mortality was not mediated by excessive CNS neutrophil accumulation. By contrast, IL-17 depletion rescued recipients of GKO CD4+ T cells from rapid mortality without diminishing neutrophils or reducing GM-CSF, associated with pathogenic Th17 cells in CNS autoimmune models. Furthermore, co-transfer of WT and GKO CD4+ T cells prolonged survival in an IFN-γ dependent manner, although IL-17 transcription was not reduced. Conclusions These data demonstrate that IL-17 mediates detrimental clinical consequences in an IFN-γ-deprived environment, independent of

  15. HTLV-1 Tax protein recruitment into IKKε and TBK1 kinase complexes enhances IFN-I expression.

    Science.gov (United States)

    Diani, Erica; Avesani, Francesca; Bergamo, Elisa; Cremonese, Giorgia; Bertazzoni, Umberto; Romanelli, Maria Grazia

    2015-02-01

    The Tax protein expressed by human T-cell leukemia virus type 1 (HTLV-1) plays a pivotal role in the deregulation of cellular pathways involved in the immune response, inflammation, cell survival, and cancer. Many of these effects derive from Tax multiple interactions with host factors, including the subunits of the IKK-complex that are required for NF-κB activation. IKKɛ and TBK1 are two IKK-related kinases that allow the phosphorylation of interferon regulatory factors that trigger IFN type I gene expression. We observed that IKKɛ and TBK1 recruit Tax into cellular immunocomplexes. We also found that TRAF3, which regulates cell receptor signaling effectors, forms complexes with Tax. Transactivation analyses revealed that expression of Tax, in presence of IKKɛ and TBK1, enhances IFN-β promoter activity, whereas the activation of NF-κB promoter is not modified. We propose that Tax may be recruited into the TBK1/IKKɛ complexes as a scaffolding-adaptor protein that enhances IFN-I gene expression. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. IFN-γ Induces Mimic Extracellular Trap Cell Death in Lung Epithelial Cells Through Autophagy-Regulated DNA Damage.

    Science.gov (United States)

    Lin, Chiou-Feng; Chien, Shun-Yi; Chen, Chia-Ling; Hsieh, Chia-Yuan; Tseng, Po-Chun; Wang, Yu-Chih

    2016-02-01

    Treatment of interferon-γ (IFN-γ) causes cell growth inhibition and cytotoxicity in lung epithelial malignancies. Regarding the induction of autophagy related to IFN-γ signaling, this study investigated the link between autophagy and IFN-γ cytotoxicity. In A549 human lung cancer cells, IFN-γ treatment induced concurrent apoptotic and nonapoptotic events. Unexpectedly, the nonapoptotic cells present mimic extracellular trap cell death (ETosis), which was regulated by caspase-3 and by autophagy induction through immunity-related GTPase family M protein 1 and activating transcription factor 6. Furthermore, IFN-γ signaling controlled mimic ETosis through a mechanism involving an autophagy- and Fas-associated protein with death domain-controlled caspase-8/-3 activation. Following caspase-mediated lamin degradation, IFN-γ caused DNA damage-associated ataxia telangiectasia and Rad3-related protein (ATR)/ataxia telangiectasia mutated (ATM)-regulated mimic ETosis. Upon ATR/ATM signaling, peptidyl arginine deiminase 4 (PAD4)-mediated histone 3 citrullination promoted mimic ETosis. Such IFN-γ-induced effects were defective in PC14PE6/AS2 human lung cancer cells, which were unsusceptible to IFN-γ-induced autophagy. Due to autophagy-based caspase cascade activation, IFNtriggers unconventional caspase-mediated DNA damage, followed by ATR/ATM-regulated PAD4-mediated histone citrullination during mimic ETosis in lung epithelial malignancy.

  17. IFNMediated Control of Bovine Major Histocompatibility Complex Class I Expression and Function via the Regulation of bta-miR-148b/152 in Bovine Endometrial Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Haichong Wu

    2018-02-01

    Full Text Available IFN-τ, a type I interferon produced by the trophoblasts of ruminants, has various important immune functions, including effects on the expression of major histocompatibility complex (MHC class I (MHC-I. A previous study has reported that IFN-τ promotes the expression of MHC-I molecules on endometrial cells. However, the immunological mechanisms by which IFN-τ regulates MHC-I molecules remain unknown. Here, we investigated which microRNA (miRNAs may be involved in the regulation of MHC-I molecule expression and function in bovine endometrial epithelial cells (bEECs. By using TargetScan 6.2 and http://www.microRNA.org, two miRNAs were suggested to target the 3′UTR of the bovine MHC-I heavy chain: bta-miR-148b and bta-miR-152. Dual luciferase reporter and miRNA mimic/inhibitor assays suggested that bta-miR-148b/152 were negatively correlated with bovine MHC-I heavy chain genes. The function of the MHC-I heavy chain was then investigated using qRT-PCR, ELISA, western blotting, immunofluorescence, and RNA interference assays in primary bEECs and an endometrial epithelial cell line (BEND. The results demonstrated that bta-miR-148b/152 could promote TLR4-triggered inflammatory responses by targeting the bovine MHC-I heavy chain, and the MHC-I molecule negatively regulated TLR4-induced inflammatory reactions may through the Fps-SHP-2 pathway. Our discovery offers novel insight into negative regulation of the TLR4 pathway and elucidates the mechanism by which bovine MHC-I molecules control congenital inflammatory reactions.

  18. An accessory to the 'Trinity': SR-As are essential pathogen sensors of extracellular dsRNA, mediating entry and leading to subsequent type I IFN responses.

    Directory of Open Access Journals (Sweden)

    Stephanie J DeWitte-Orr

    2010-03-01

    Full Text Available Extracellular RNA is becoming increasingly recognized as a signaling molecule. Virally derived double stranded (dsRNA released into the extracellular space during virus induced cell lysis acts as a powerful inducer of classical type I interferon (IFN responses; however, the receptor that mediates this response has not been identified. Class A scavenger receptors (SR-As are likely candidates due to their cell surface expression and ability to bind nucleic acids. In this study, we investigated a possible role for SR-As in mediating type I IFN responses induced by extracellular dsRNA in fibroblasts, a predominant producer of IFNbeta. Fibroblasts were found to express functional SR-As, even SR-A species thought to be macrophage specific. SR-A specific competitive ligands significantly blocked extracellular dsRNA binding, entry and subsequent interferon stimulated gene (ISG induction. Candidate SR-As were systematically investigated using RNAi and the most dramatic inhibition in responses was observed when all candidate SR-As were knocked down in unison. Partial inhibition of dsRNA induced antiviral responses was observed in vivo in SR-AI/II(-/- mice compared with WT controls. The role of SR-As in mediating extracellular dsRNA entry and subsequent induced antiviral responses was observed in both murine and human fibroblasts. SR-As appear to function as 'carriers', facilitating dsRNA entry and delivery to the established dsRNA sensing receptors, specifically TLR3, RIGI and MDA-5. Identifying SR-As as gatekeepers of the cell, mediating innate antiviral responses, represents a novel function for this receptor family and provides insight into how cells recognize danger signals associated with lytic virus infections. Furthermore, the implications of a cell surface receptor capable of recognizing extracellular RNA may exceed beyond viral immunity to mediating other important innate immune functions.

  19. Critical role of IFN-gamma in CFA-mediated protection of NOD mice from diabetes development.

    Science.gov (United States)

    Mori, Yoshiko; Kodaka, Tetsuro; Kato, Takako; Kanagawa, Edith M; Kanagawa, Osami

    2009-11-01

    IFN-gamma signaling-deficient non-obese diabetic (NOD) mice develop diabetes with similar kinetics to those of wild-type NOD mice. However, the immunization of IFN-gamma signaling-deficient NOD mice with CFA failed to induce long-term protection, whereas wild-type NOD mice receiving CFA remained diabetes-free. CFA also failed to protect IFN-gamma receptor-deficient (IFN-gammaR(-/-)) NOD mice from the autoimmune rejection of transplanted islets, as it does in diabetic NOD mice, and from disease transfer by spleen cells from diabetic NOD mice. These data clearly show that the pro-inflammatory cytokine IFN-gamma is necessary for the CFA-mediated protection of NOD mice from diabetes. There is no difference in the T(h)1/T(h)17 balance between IFN-gammaR(-/-) NOD and wild-type NOD mice. There is also no difference in the total numbers and percentages of regulatory T (Treg) cells in the lymph node CD4(+) T-cell populations between IFN-gammaR(-/-) NOD and wild-type NOD mice. However, pathogenic T cells lacking IFN-gammaR are resistant to the suppressive effect of Treg cells, both in vivo and in vitro. Therefore, it is likely that CFA-mediated protection against diabetes development depends on a change in the balance between Treg cells and pathogenic T cells, and IFN-gamma signaling seems to control the susceptibility of pathogenic T cells to the inhibitory activity of Treg cells.

  20. Biodistribution analysis of 125I-albumin-IFN-alpha2b fusion protein in rats

    International Nuclear Information System (INIS)

    Zhou Yaoyuan; Zhang Rongjun; Cai Gangming; Gu Xiaobo; Jiang Mengjun; Zhang Bo; Yang Min; Cao Guoxian; Yang Jianliang

    2009-01-01

    125 I-albumin-IFN-alpha2b was prepared with the methods of Ch-T and purified with PD-10 column. The radiochemical purity was measured with TCA (trichloroacetic acid) precipitation. The antiviral activities of 125 I-albumin-IFN-alpha2b and albumin-IFN-alpha2b were compared with WISH/VSV system in vitro. SD rats were injected with 125 I-albumin-IFN-alpha2b subcutaneously and sacrificed at 0.5, 2, 6, 24, 48, 90, 180 and 300 h post-injection. Selected organs were dissected, weighed and their radioactivity was measured using γ-counter. The accumulated radioactivity in the tissues was calculated in terms of percentage of injected dose per gram organ (%ID·g -1 ). The labeling yield was 82.72%. The radiochemical purity of 125 I-albumin-IFN-alpha2b was 95.53%, and its radioactivity was 0.26 MBq/μg. The antiviral bioactivities of albumin-IFN-alpha2b and 125 I-albumin- IFN-alpha2b did not change. Biodistribution analysis of 125 I-albumin-IFN-alpha2b in rats showed that concentrated 125 I-albumin-IFN-alpha2b in blood reached maximum at 6 h post injection, and eliminated slowly. No specific accumulation was seen in other tissues. 125 I-albumin-IFN-alpha2b could maintain in peripheral blood for a long time and it meant albumin-IFN-alpha2b would be an effective long-term interferon. (authors)

  1. RIG-I-Like Receptor Signaling in Singleton-Merten Syndrome

    Directory of Open Access Journals (Sweden)

    Changming Lu

    2017-09-01

    Full Text Available Singleton-Merten syndrome (SMS is an autosomal dominant, multi-system innate immune disorder characterized by early and severe aortic and valvular calcification, dental and skeletal abnormalities, psoriasis, glaucoma, and other varying clinical findings. Recently we identified a specific gain-of-function mutation in IFIH1, interferon induced with helicase C domain 1, segregated with this disease. SMS disease without hallmark dental anomalies, termed atypical SMS, has recently been reported caused by variants in DDX58, DEXD/H-box helicase 58. IFIH1 and DDX58 encode retinoic acid-inducible gene I (RIG-I-like receptors family members melanoma differentiation-associated gene 5 and RIG-I, respectively. These cytosolic pattern recognition receptors function in viral RNA detection initiating an innate immune response through independent pathways that promote type I and type III interferon expression and proinflammatory cytokines. In this review, we focus on SMS as an innate immune disorder summarizing clinical features, molecular aspects of the pathogenetic pathway and discussing underlying mechanisms of the disease.

  2. Wild type measles virus attenuation independent of type I IFN

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    Horvat Branka

    2008-02-01

    Full Text Available Abstract Background Measles virus attenuation has been historically performed by adaptation to cell culture. The current dogma is that attenuated virus strains induce more type I IFN and are more resistant to IFN-induced protection than wild type (wt. Results The adaptation of a measles virus isolate (G954-PBL by 13 passages in Vero cells induced a strong attenuation of this strain in vivo. The adapted virus (G954-V13 differs from its parental strain by only 5 amino acids (4 in P/V/C and 1 in the M gene. While a vaccine strain, Edmonston Zagreb, could replicate equally well in various primate cells, both G954 strains exhibited restriction to the specific cell type used initially for their propagation. Surprisingly, we observed that both G954 strains induced type I IFN, the wt strain inducing even more than the attenuated ones, particularly in human plasmacytoid Dendritic Cells. Type I IFN-induced protection from the infection of both G954 strains depended on the cell type analyzed, being less efficient in the cells used to grow the viral strain. Conclusion Thus, mutations in M and P/V/C proteins can critically affect MV pathogenicity, cellular tropism and lead to virus attenuation without interfering with the α/β IFN system.

  3. Characterization of the bovine type I IFN locus: rearrangements, expansions, and novel subfamilies

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    Walker Angela M

    2009-04-01

    Full Text Available Abstract Background The Type I interferons (IFN have major roles in the innate immune response to viruses, a function that is believed to have led to expansion in the number and complexity of their genes, although these genes have remained confined to single chromosomal region in all mammals so far examined. IFNB and IFNE define the limits of the locus, with all other Type I IFN genes except IFNK distributed between these boundaries, strongly suggesting that the locus has broadened as IFN genes duplicated and then evolved into a series of distinct families. Results The Type I IFN locus in Bos taurus has undergone significant rearrangement and expansion compared to mouse and human, however, with the constituent genes separated into two sub-loci separated by >700 kb. The IFNW family is greatly expanded, comprising 24 potentially functional genes and at least 8 pseudogenes. The IFNB (n = 6, represented in human and mouse by one copy, are also present as multiple copies in Bos taurus. The IFNT, which encode a non-virally inducible, ruminant-specific IFN secreted by the pre-implantation conceptus, are represented by three genes and two pseudogenes. The latter have sequences intermediate between IFNT and IFNW. A new Type I IFN family (IFNX of four members, one of which is a pseudogene, appears to have diverged from the IFNA lineage at least 83 million years ago, but is absent in all other sequenced genomes with the possible exception of the horse, a non-ruminant herbivore. Conclusion In summary, we have provided the first comprehensive annotation of the Type I IFN locus in Bos taurus, thereby providing an insight into the functional evolution of the Type I IFN in ruminants. The diversity and global spread of the ruminant species may have required an expansion of the Type I IFN locus and its constituent genes to provide broad anti-viral protection required for foraging and foregut fermentation.

  4. HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

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    Héla Saïdi

    2016-02-01

    Full Text Available Plasmacytoid dendritic cells (pDCs are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7 and 9 (TLR9 ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN-α-mediated

  5. HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

    Science.gov (United States)

    Saïdi, Héla; Bras, Marlène; Formaglio, Pauline; Melki, Marie-Thérèse; Charbit, Bruno; Herbeuval, Jean-Philippe; Gougeon, Marie-Lise

    2016-02-01

    Plasmacytoid dendritic cells (pDCs) are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7) and 9 (TLR9) ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β) in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN-α-mediated

  6. Influenza A virus protein PB1-F2 exacerbates IFN-beta expression of human respiratory epithelial cells.

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    Le Goffic, Ronan; Bouguyon, Edwige; Chevalier, Christophe; Vidic, Jasmina; Da Costa, Bruno; Leymarie, Olivier; Bourdieu, Christiane; Decamps, Laure; Dhorne-Pollet, Sophie; Delmas, Bernard

    2010-10-15

    The PB1-F2 protein of the influenza A virus (IAV) contributes to viral pathogenesis by a mechanism that is not well understood. PB1-F2 was shown to modulate apoptosis and to be targeted by the CD8(+) T cell response. In this study, we examined the downstream effects of PB1-F2 protein during IAV infection by measuring expression of the cellular genes in response to infection with wild-type WSN/33 and PB1-F2 knockout viruses in human lung epithelial cells. Wild-type virus infection resulted in a significant induction of genes involved in innate immunity. Knocking out the PB1-F2 gene strongly decreased the magnitude of expression of cellular genes implicated in antiviral response and MHC class I Ag presentation, suggesting that PB1-F2 exacerbates innate immune response. Biological network analysis revealed the IFN pathway as a link between PB1-F2 and deregulated genes. Using quantitative RT-PCR and IFN-β gene reporter assay, we determined that PB1-F2 mediates an upregulation of IFN-β expression that is dependent on NF-κB but not on AP-1 and IFN regulatory factor-3 transcription factors. Recombinant viruses knocked out for the PB1-F2 and/or the nonstructural viral protein 1 (the viral antagonist of the IFN response) genes provide further evidence that PB1-F2 increases IFN-β expression and that nonstructural viral protein 1 strongly antagonizes the effect of PB1-F2 on the innate response. Finally, we compared the effect of PB1-F2 variants taken from several IAV strains on IFN-β expression and found that PB1-F2-mediated IFN-β induction is significantly influenced by its amino acid sequence, demonstrating its importance in the host cell response triggered by IAV infection.

  7. Inflammatory impact of IFN-γ in CD8+ T cell-mediated lung injury is mediated by both Stat1-dependent and -independent pathways

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    Ramana, Chilakamarti V.; DeBerge, Matthew P.; Kumar, Aseem; Alia, Christopher S.; Durbin, Joan E.

    2015-01-01

    Influenza infection results in considerable pulmonary pathology, a significant component of which is mediated by CD8+ T cell effector functions. To isolate the specific contribution of CD8+ T cells to lung immunopathology, we utilized a nonviral murine model in which alveolar epithelial cells express an influenza antigen and injury is initiated by adoptive transfer of influenza-specific CD8+ T cells. We report that IFN-γ production by adoptively transferred influenza-specific CD8+ T cells is a significant contributor to acute lung injury following influenza antigen recognition, in isolation from its impact on viral clearance. CD8+ T cell production of IFN-γ enhanced lung epithelial cell expression of chemokines and the subsequent recruitment of inflammatory cells into the airways. Surprisingly, Stat1 deficiency in the adoptive-transfer recipients exacerbated the lung injury that was mediated by the transferred influenza-specific CD8+ T cells but was still dependent on IFN-γ production by these cells. Loss of Stat1 resulted in sustained activation of Stat3 signaling, dysregulated chemokine expression, and increased infiltration of the airways by inflammatory cells. Taken together, these data identify important roles for IFN-γ signaling and Stat1-independent IFN-γ signaling in regulating CD8+ T cell-mediated acute lung injury. This is the first study to demonstrate an anti-inflammatory effect of Stat1 on CD8+ T cell-mediated lung immunopathology without the complication of differences in viral load. PMID:25617378

  8. Alveolar macrophage–derived type I interferons orchestrate innate immunity to RSV through recruitment of antiviral monocytes

    Science.gov (United States)

    Goritzka, Michelle; Makris, Spyridon; Kausar, Fahima; Durant, Lydia R.; Pereira, Catherine; Kumagai, Yutaro; Culley, Fiona J.; Mack, Matthias; Akira, Shizuo

    2015-01-01

    Type I interferons (IFNs) are important for host defense from viral infections, acting to restrict viral production in infected cells and to promote antiviral immune responses. However, the type I IFN system has also been associated with severe lung inflammatory disease in response to respiratory syncytial virus (RSV). Which cells produce type I IFNs upon RSV infection and how this directs immune responses to the virus, and potentially results in pathological inflammation, is unclear. Here, we show that alveolar macrophages (AMs) are the major source of type I IFNs upon RSV infection in mice. AMs detect RSV via mitochondrial antiviral signaling protein (MAVS)–coupled retinoic acid–inducible gene 1 (RIG-I)–like receptors (RLRs), and loss of MAVS greatly compromises innate immune restriction of RSV. This is largely attributable to loss of type I IFN–dependent induction of monocyte chemoattractants and subsequent reduced recruitment of inflammatory monocytes (infMo) to the lungs. Notably, the latter have potent antiviral activity and are essential to control infection and lessen disease severity. Thus, infMo recruitment constitutes an important and hitherto underappreciated, cell-extrinsic mechanism of type I IFN–mediated antiviral activity. Dysregulation of this system of host antiviral defense may underlie the development of RSV-induced severe lung inflammation. PMID:25897172

  9. Viral RNA-Unprimed Rig-I Restrains Stat3 Activation in the Modulation of Regulatory T Cell/Th17 Cell Balance.

    Science.gov (United States)

    Yang, Hui; Guo, He-Zhou; Li, Xian-Yang; Lin, Jian; Zhang, Wu; Zhao, Jun-Mei; Zhang, Hong-Xin; Chen, Sai-Juan; Chen, Zhu; Zhu, Jiang

    2017-07-01

    Innate immunity activation by viral RNA-primed retinoid acid inducible gene-I (Rig-I) in CD4 + T cells antagonizes TGFβ signaling to suppress the differentiation of regulatory T cells (Tregs). However, how viral RNA-unliganded Rig-I (apo-Rig-I) modulates Treg generation remains unclear. In this article, we show that, in the absence of viral infection, Treg differentiation of Rig-I -/- CD4 + T cells was compromised, in the presence of increased generation of Th17 cells and overactivation of Stat3, a critical regulator tilting the Treg/Th17 cell balance. Mechanistically, apo-Rig-I physically associates with Stat3, thereby inhibiting Jak1's association with Stat3 while facilitating Shp2's association to inhibit p-Stat3 levels. Interestingly, inhibition of Stat3 ameliorates the Treg/Th17 imbalance and the colitis observed in Rig-I -/- mice. Collectively, these results uncover an independent functional contribution of the apo-Rig-I/Stat3 interaction in the maintenance of Treg/Th17 cell balance. Copyright © 2017 by The American Association of Immunologists, Inc.

  10. De Novo Transcriptome Analysis Shows That SAV-3 Infection Upregulates Pattern Recognition Receptors of the Endosomal Toll-Like and RIG-I-Like Receptor Signaling Pathways in Macrophage/Dendritic Like TO-Cells

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    Cheng Xu

    2016-04-01

    Full Text Available A fundamental step in cellular defense mechanisms is the recognition of “danger signals” made of conserved pathogen associated molecular patterns (PAMPs expressed by invading pathogens, by host cell germ line coded pattern recognition receptors (PRRs. In this study, we used RNA-seq and the Kyoto encyclopedia of genes and genomes (KEGG to identify PRRs together with the network pathway of differentially expressed genes (DEGs that recognize salmonid alphavirus subtype 3 (SAV-3 infection in macrophage/dendritic like TO-cells derived from Atlantic salmon (Salmo salar L headkidney leukocytes. Our findings show that recognition of SAV-3 in TO-cells was restricted to endosomal Toll-like receptors (TLRs 3 and 8 together with RIG-I-like receptors (RLRs and not the nucleotide-binding oligomerization domain-like receptors NOD-like receptor (NLRs genes. Among the RLRs, upregulated genes included the retinoic acid inducible gene I (RIG-I, melanoma differentiation association 5 (MDA5 and laboratory of genetics and physiology 2 (LGP2. The study points to possible involvement of the tripartite motif containing 25 (TRIM25 and mitochondrial antiviral signaling protein (MAVS in modulating RIG-I signaling being the first report that links these genes to the RLR pathway in SAV-3 infection in TO-cells. Downstream signaling suggests that both the TLR and RLR pathways use interferon (IFN regulatory factors (IRFs 3 and 7 to produce IFN-a2. The validity of RNA-seq data generated in this study was confirmed by quantitative real time qRT-PCR showing that genes up- or downregulated by RNA-seq were also up- or downregulated by RT-PCR. Overall, this study shows that de novo transcriptome assembly identify key receptors of the TLR and RLR sensors engaged in host pathogen interaction at cellular level. We envisage that data presented here can open a road map for future intervention strategies in SAV infection of salmon.

  11. Suppression of type I and type III IFN signalling by NSs protein of severe fever with thrombocytopenia syndrome virus through inhibition of STAT1 phosphorylation and activation.

    Science.gov (United States)

    Chaudhary, Vidyanath; Zhang, Shuo; Yuen, Kit-San; Li, Chuan; Lui, Pak-Yin; Fung, Sin-Yee; Wang, Pei-Hui; Chan, Chi-Ping; Li, Dexin; Kok, Kin-Hang; Liang, Mifang; Jin, Dong-Yan

    2015-11-01

    Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne pathogen causing significant morbidity and mortality in Asia. NSs protein of SFTSV is known to perturb type I IFN induction and signalling, but the mechanism remains to be fully understood. Here, we showed the suppression of both type I and type III IFN signalling by SFTSV NSs protein is mediated through inhibition of STAT1 phosphorylation and activation. Infection with live SFTSV or expression of NSs potently suppressed IFN-stimulated genes but not NFkB activation. NSs was capable of counteracting the activity of IFN-α1, IFN-β, IFN-λ1 and IFN-λ2. Mechanistically, NSs associated with STAT1 and STAT2, mitigated IFN-β-induced phosphorylation of STAT1 at S727, and reduced the expression and activity of STAT1 protein in IFN-β-treated cells, resulting in the inhibition of STAT1 and STAT2 recruitment to IFNstimulated promoters. Taken together, SFTSV NSs protein is an IFN antagonist that suppresses phosphorylation and activation of STAT1.

  12. IFN-γ signaling to astrocytes protects from autoimmune mediated neurological disability.

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    Claudia Hindinger

    Full Text Available Demyelination and axonal degeneration are determinants of progressive neurological disability in patients with multiple sclerosis (MS. Cells resident within the central nervous system (CNS are active participants in development, progression and subsequent control of autoimmune disease; however, their individual contributions are not well understood. Astrocytes, the most abundant CNS cell type, are highly sensitive to environmental cues and are implicated in both detrimental and protective outcomes during autoimmune demyelination. Experimental autoimmune encephalomyelitis (EAE was induced in transgenic mice expressing signaling defective dominant-negative interferon gamma (IFN-γ receptors on astrocytes to determine the influence of inflammation on astrocyte activity. Inhibition of IFN-γ signaling to astrocytes did not influence disease incidence, onset, initial progression of symptoms, blood brain barrier (BBB integrity or the composition of the acute CNS inflammatory response. Nevertheless, increased demyelination at peak acute disease in the absence of IFN-γ signaling to astrocytes correlated with sustained clinical symptoms. Following peak disease, diminished clinical remission, increased mortality and sustained astrocyte activation within the gray matter demonstrate a critical role of IFN-γ signaling to astrocytes in neuroprotection. Diminished disease remission was associated with escalating demyelination, axonal degeneration and sustained inflammation. The CNS infiltrating leukocyte composition was not altered; however, decreased IL-10 and IL-27 correlated with sustained disease. These data indicate that astrocytes play a critical role in limiting CNS autoimmune disease dependent upon a neuroprotective signaling pathway mediated by engagement of IFN-γ receptors.

  13. Seneca Valley Virus Suppresses Host Type I Interferon Production by Targeting Adaptor Proteins MAVS, TRIF, and TANK for Cleavage.

    Science.gov (United States)

    Qian, Suhong; Fan, Wenchun; Liu, Tingting; Wu, Mengge; Zhang, Huawei; Cui, Xiaofang; Zhou, Yun; Hu, Junjie; Wei, Shaozhong; Chen, Huanchun; Li, Xiangmin; Qian, Ping

    2017-08-15

    the Toll-like receptor 3 (TLR3)-mediated and retinoic acid-inducible gene I (RIG-I)-like receptor (RLR)-mediated signaling pathway. We also found that SVV is sensitive to IFN-β. These findings increase our understanding of the interaction between SVV and host innate immunity. Copyright © 2017 American Society for Microbiology.

  14. MDA5 Detects the Double-Stranded RNA Replicative Form in Picornavirus-Infected Cells

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    Qian Feng

    2012-11-01

    Full Text Available RIG-I and MDA5 are cytosolic RNA sensors that play a critical role in innate antiviral responses. Major advances have been made in identifying RIG-I ligands, but our knowledge of the ligands for MDA5 remains restricted to data from transfection experiments mostly using poly(I:C, a synthetic dsRNA mimic. Here, we dissected the IFN-α/β-stimulatory activity of different viral RNA species produced during picornavirus infection, both by RNA transfection and in infected cells in which specific steps of viral RNA replication were inhibited. Our results show that the incoming genomic plus-strand RNA does not activate MDA5, but minus-strand RNA synthesis and production of the 7.5 kbp replicative form trigger a strong IFN-α/β response. IFN-α/β production does not rely on plus-strand RNA synthesis and thus generation of the partially double-stranded replicative intermediate. This study reports MDA5 activation by a natural RNA ligand under physiological conditions.

  15. TPL-2-ERK1/2 signaling promotes host resistance against intracellular bacterial infection by negative regulation of type I IFN production.

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    McNab, Finlay W; Ewbank, John; Rajsbaum, Ricardo; Stavropoulos, Evangelos; Martirosyan, Anna; Redford, Paul S; Wu, Xuemei; Graham, Christine M; Saraiva, Margarida; Tsichlis, Philip; Chaussabel, Damien; Ley, Steven C; O'Garra, Anne

    2013-08-15

    Tuberculosis, caused by Mycobacterium tuberculosis, remains a leading cause of mortality and morbidity worldwide, causing ≈ 1.4 million deaths per year. Key immune components for host protection during tuberculosis include the cytokines IL-12, IL-1, and TNF-α, as well as IFN-γ and CD4(+) Th1 cells. However, immune factors determining whether individuals control infection or progress to active tuberculosis are incompletely understood. Excess amounts of type I IFN have been linked to exacerbated disease during tuberculosis in mouse models and to active disease in patients, suggesting tight regulation of this family of cytokines is critical to host resistance. In addition, the immunosuppressive cytokine IL-10 is known to inhibit the immune response to M. tuberculosis in murine models through the negative regulation of key proinflammatory cytokines and the subsequent Th1 response. We show in this study, using a combination of transcriptomic analysis, genetics, and pharmacological inhibitors, that the TPL-2-ERK1/2 signaling pathway is important in mediating host resistance to tuberculosis through negative regulation of type I IFN production. The TPL-2-ERK1/2 signaling pathway regulated production by macrophages of several cytokines important in the immune response to M. tuberculosis as well as regulating induction of a large number of additional genes, many in a type I IFN-dependent manner. In the absence of TPL-2 in vivo, excess type I IFN promoted IL-10 production and exacerbated disease. These findings describe an important regulatory mechanism for controlling tuberculosis and reveal mechanisms by which type I IFN may promote susceptibility to this important disease.

  16. Pan-viral specificity of IFN-induced genes reveals new roles for cGAS in innate immunity

    Science.gov (United States)

    Schoggins, John W.; MacDuff, Donna A.; Imanaka, Naoko; Gainey, Maria D.; Shrestha, Bimmi; Eitson, Jennifer L.; Mar, Katrina B.; Richardson, R. Blake; Ratushny, Alexander V.; Litvak, Vladimir; Dabelic, Rea; Manicassamy, Balaji; Aitchison, John D.; Aderem, Alan; Elliott, Richard M.; García-Sastre, Adolfo; Racaniello, Vincent; Snijder, Eric J.; Yokoyama, Wayne M.; Diamond, Michael S.; Virgin, Herbert W.; Rice, Charles M.

    2014-01-01

    The type I interferon (IFN) response protects cells from viral infection by inducing hundreds of interferon-stimulated genes (ISGs), some of which encode direct antiviral effectors. Recent screening studies have begun to catalogue ISGs with antiviral activity against several RNA and DNA viruses. However, antiviral ISG specificity across multiple distinct classes of viruses remains largely unexplored. Here we used an ectopic expression assay to screen a library of more than 350 human ISGs for effects on 14 viruses representing 7 families and 11 genera. We show that 47 genes inhibit one or more viruses, and 25 genes enhance virus infectivity. Comparative analysis reveals that the screened ISGs target positive-sense single-stranded RNA viruses more effectively than negative-sense single-stranded RNA viruses. Gene clustering highlights the cytosolic DNA sensor cyclic GMP-AMP synthase (cGAS, also known as MB21D1) as a gene whose expression also broadly inhibits several RNA viruses. In vitro, lentiviral delivery of enzymatically active cGAS triggers a STING-dependent, IRF3-mediated antiviral program that functions independently of canonical IFN/STAT1 signalling. In vivo, genetic ablation of murine cGAS reveals its requirement in the antiviral response to two DNA viruses, and an unappreciated contribution to the innate control of an RNA virus. These studies uncover new paradigms for the preferential specificity of IFN-mediated antiviral pathways spanning several virus families.

  17. FTR83, a Member of the Large Fish-Specific finTRIM Family, Triggers IFN Pathway and Counters Viral Infection

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    Christelle Langevin

    2017-05-01

    Full Text Available Tripartite motif (TRIM proteins are involved in various cellular functions and constitute key factors of the antiviral innate immune response. TRIM proteins can bind viral particles directly, sending them to degradation by the proteasome, or ubiquitinate signaling molecules leading to upregulation of innate immunity. TRIM proteins are present in across metazoans but are particularly numerous in vertebrates where genes comprising a B30.2 domain have been often duplicated. In fish, a TRIM subset named finTRIM is highly diversified, with large gene numbers and clear signatures of positive selection in the B30.2 domain suggesting they may be involved in antiviral mechanisms. finTRIM provides a beautiful model to investigate the primordial implication of B30.2 TRIM subsets in the arsenal of vertebrate antiviral defenses. We show here that ftr83, a zebrafish fintrim gene mainly expressed in the gills, skin and pharynx, encodes a protein affording a potent antiviral activity. In vitro, overexpression of FTR83, but not of its close relative FTR82, induced IFN and IFN-stimulated gene expression and afforded protection against different enveloped and non-enveloped RNA viruses. The kinetics of IFN induction paralleled the development of the antiviral activity, which was abolished by a dominant negative IRF3 mutant. In the context of a viral infection, FTR83 potentiated the IFN response. Expression of chimeric proteins in which the B30.2 domain of FTR83 and the non-protective FTR82 had been exchanged, showed that IFN upregulation and antiviral activity requires both the Ring/BBox/Coiled coil domain (supporting E3 ubiquitin ligase and the B30.2 domain of FTR83. Finally, loss of function experiments in zebrafish embryos confirms that ftr83 mediates antiviral activity in vivo. Our results show that a member of the largest TRIM subset observed in fish upregulates type I IFN response and afford protection against viral infections, supporting that TRIMs are key

  18. IFN regulatory factor 1 restricts hepatitis E virus replication by activating STAT1 to induce antiviral IFN-stimulated genes.

    Science.gov (United States)

    Xu, Lei; Zhou, Xinying; Wang, Wenshi; Wang, Yijin; Yin, Yuebang; Laan, Luc J W van der; Sprengers, Dave; Metselaar, Herold J; Peppelenbosch, Maikel P; Pan, Qiuwei

    2016-10-01

    IFN regulatory factor 1 (IRF1) is one of the most important IFN-stimulated genes (ISGs) in cellular antiviral immunity. Although hepatitis E virus (HEV) is a leading cause of acute hepatitis worldwide, how ISGs counteract HEV infection is largely unknown. This study was conducted to investigate the effect of IRF1 on HEV replication. Multiple cell lines were used in 2 models that harbor HEV. In different HEV cell culture systems, IRF1 effectively inhibited HEV replication. IRF1 did not trigger IFN production, and chromatin immunoprecipitation sequencing data analysis revealed that IRF1 bound to the promoter region of signal transducers and activators of transcription 1 (STAT1). Functional assay confirmed that IRF1 could drive the transcription of STAT1, resulting in elevation of total and phosphorylated STAT1 proteins and further activating the transcription of a panel of downstream antiviral ISGs. By pharmacological inhibitors and RNAi-mediated gene-silencing approaches, we revealed that antiviral function of IRF1 is dependent on the JAK-STAT cascade. Furthermore, induction of ISGs and the anti-HEV effect of IRF1 overlapped that of IFNα, but was potentiated by ribavirin. We demonstrated that IRF1 effectively inhibits HEV replication through the activation of the JAK-STAT pathway, and the subsequent transcription of antiviral ISGs, but independent of IFN production.-Xu, L., Zhou, X., Wang, W., Wang, Y., Yin, Y., van der Laan, L. J. W., Sprengers, D., Metselaar, H. J., Peppelenbosch, M. P., Pan, Q. IFN regulatory factor 1 restricts hepatitis E virus replication by activating STAT1 to induce antiviral IFN-stimulated genes. © FASEB.

  19. Local therapy with CpG motifs in a murine model of allergic airway inflammation in IFN-beta knock-out mice

    DEFF Research Database (Denmark)

    Matheu, Victor; Treschow, Alexandra; Teige, Ingrid

    2005-01-01

    BACKGROUND: CpG oligodeoxynucleotides (CpG-ODN) are capable of inducing high amounts of type I IFNs with many immunomodulatory properties. Furthermore, type-I IFNs have been proposed to play a key role in mediating effects of CpG-ODN. The precise role of IFN-beta in the immunomodulatory effects o...

  20. Interferon γ-inducible protein (IFI) 16 transcriptionally regulates type i interferons and other interferon-stimulated genes and controls the interferon response to both DNA and RNA viruses.

    Science.gov (United States)

    Thompson, Mikayla R; Sharma, Shruti; Atianand, Maninjay; Jensen, Søren B; Carpenter, Susan; Knipe, David M; Fitzgerald, Katherine A; Kurt-Jones, Evelyn A

    2014-08-22

    The interferon γ-inducible protein 16 (IFI16) has recently been linked to the detection of nuclear and cytosolic DNA during infection with herpes simplex virus-1 and HIV. IFI16 binds dsDNA via HIN200 domains and activates stimulator of interferon genes (STING), leading to TANK (TRAF family member-associated NF-κB activator)-binding kinase-1 (TBK1)-dependent phosphorylation of interferon regulatory factor (IRF) 3 and transcription of type I interferons (IFNs) and related genes. To better understand the role of IFI16 in coordinating type I IFN gene regulation, we generated cell lines with stable knockdown of IFI16 and examined responses to DNA and RNA viruses as well as cyclic dinucleotides. As expected, stable knockdown of IFI16 led to a severely attenuated type I IFN response to DNA ligands and viruses. In contrast, expression of the NF-κB-regulated cytokines IL-6 and IL-1β was unaffected in IFI16 knockdown cells, suggesting that the role of IFI16 in sensing these triggers was unique to the type I IFN pathway. Surprisingly, we also found that knockdown of IFI16 led to a severe attenuation of IFN-α and the IFN-stimulated gene retinoic acid-inducible gene I (RIG-I) in response to cyclic GMP-AMP, a second messenger produced by cyclic GMP-AMP synthase (cGAS) as well as RNA ligands and viruses. Analysis of IFI16 knockdown cells revealed compromised occupancy of RNA polymerase II on the IFN-α promoter in these cells, suggesting that transcription of IFN-stimulated genes is dependent on IFI16. These results indicate a broader role for IFI16 in the regulation of the type I IFN response to RNA and DNA viruses in antiviral immunity. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. UBXN1 Interferes with Rig-I-like Receptor-Mediated Antiviral Immune Response by Targeting MAVS

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    Penghua Wang

    2013-04-01

    Full Text Available RNA viruses are sensed by RIG-I-like receptors (RLRs, which signal through a mitochondria-associated adaptor molecule, MAVS, resulting in systemic antiviral immune responses. Although RLR signaling is essential for limiting RNA virus replication, it must be stringently controlled to prevent damage from inflammation. We demonstrate here that among all tested UBX-domain-containing protein family members, UBXN1 exhibits the strongest inhibitory effect on RNA-virus-induced type I interferon response. UBXN1 potently inhibits RLR- and MAVS-induced, but not TLR3-, TLR4-, or DNA-virus-induced innate immune responses. Depletion of UBXN1 enhances virus-induced innate immune responses, including those resulting from RNA viruses such as vesicular stomatitis, Sendai, West Nile, and dengue virus infection, repressing viral replication. Following viral infection, UBXN1 is induced, binds to MAVS, interferes with intracellular MAVS oligomerization, and disrupts the MAVS/TRAF3/TRAF6 signalosome. These findings underscore a critical role of UBXN1 in the modulation of a major antiviral signaling pathway.

  2. Identification of DreI as an antiviral factor regulated by RLR signaling pathway.

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    Shun Li

    Full Text Available BACKGROUND: Retinoic acid-inducible gene I (RIG-I-like receptors (RLRs had been demonstrated to prime interferon (IFN response against viral infection via the conserved RLR signaling in fish, and a novel fish-specific gene, the grass carp reovirus (GCRV-induced gene 2 (Gig2, had been suggested to play important role in host antiviral response. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we cloned and characterized zebrafish Gig2 homolog (named Danio rerio Gig2-I, DreI, and revealed its antiviral role and expressional regulation signaling pathway. RT-PCR, Western blot and promoter activity assay indicate that DreI can be induced by poly I:C, spring viremia of carp virus (SVCV and recombinant IFN (rIFN, showing that DreI is a typical ISG. Using the pivotal signaling molecules of RLR pathway, including RIG-I, MDA5 and IRF3 from crucian carp, it is found that DreI expression is regulated by RLR cascade and IRF3 plays an important role in this regulation. Furthermore, promoter mutation assay confirms that the IFN-stimulated regulatory elements (ISRE in the 5' flanking region of DreI is essential for its induction. Finally, overexpression of DreI leads to establish a strong antiviral state against SVCV and Rana grylio virus (RGV infection in EPC (Epithelioma papulosum cyprinid cells. CONCLUSIONS/SIGNIFICANCE: These data indicate that DreI is an antiviral protein, which is regulated by RLR signaling pathway.

  3. Interferon-alpha triggers B cell effector 1 (Be1 commitment.

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    Marie-Ghislaine de Goër de Herve

    Full Text Available B-cells can contribute to the pathogenesis of autoimmune diseases not only through auto-antibody secretion but also via cytokine production. Therapeutic depletion of B-cells influences the functions and maintenance of various T-cell subsets. The mechanisms governing the functional heterogeneity of B-cell subsets as cytokine-producing cells are poorly understood. B-cells can differentiate into two functionally polarized effectors, one (B-effector-1-cells producing a Th-1-like cytokine pattern and the other (Be2 producing a Th-2-like pattern. IL-12 and IFN-γ play a key role in Be1 polarization, but the initial trigger of Be1 commitment is unclear. Type-I-interferons are produced early in the immune response and prime several processes involved in innate and adaptive responses. Here, we report that IFNtriggers a signaling cascade in resting human naive B-cells, involving STAT4 and T-bet, two key IFN-γ gene imprinting factors. IFN-α primed naive B-cells for IFN-γ production and increased IFN-γ gene responsiveness to IL-12. IFN-γ continues this polarization by re-inducing T-bet and up-regulating IL-12Rβ2 expression. IFN-α and IFN-γ therefore pave the way for the action of IL-12. These results point to a coordinated action of IFN-α, IFN-γ and IL-12 in Be1 polarization of naive B-cells, and may provide new insights into the mechanisms by which type-I-interferons favor autoimmunity.

  4. Selective RNA targeting and regulated signaling by RIG-I is controlled by coordination of RNA and ATP binding.

    Science.gov (United States)

    Fitzgerald, Megan E; Rawling, David C; Potapova, Olga; Ren, Xiaoming; Kohlway, Andrew; Pyle, Anna Marie

    2017-02-17

    RIG-I is an innate immune receptor that detects and responds to infection by deadly RNA viruses such as influenza, and Hepatitis C. In the cytoplasm, RIG-I is faced with a difficult challenge: it must sensitively detect viral RNA while ignoring the abundance of host RNA. It has been suggested that RIG-I has a ‘proof-reading’ mechanism for rejecting host RNA targets, and that disruptions of this selectivity filter give rise to autoimmune diseases. Here, we directly monitor RNA proof-reading by RIG-I and we show that it is controlled by a set of conserved amino acids that couple RNA and ATP binding to the protein (Motif III). Mutations of this motif directly modulate proof-reading by eliminating or enhancing selectivity for viral RNA, with major implications for autoimmune disease and cancer. More broadly, the results provide a physical explanation for the ATP-gated behavior of SF2 RNA helicases and receptor proteins.

  5. Bioinformatics analysis of the factors controlling type I IFN gene expression in autoimmune disease and virus-induced immunity

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    Di eFeng

    2013-09-01

    Full Text Available Patients with systemic lupus erythematosus (SLE and Sjögren's syndrome (SS display increased levels of type I IFN-induced genes. Plasmacytoid dendritic cells (PDCs are natural interferon producing cells and considered to be a primary source of IFN-α in these two diseases. Differential expression patterns of type I IFN inducible transcripts can be found in different immune cell subsets and in patients with both active and inactive autoimmune disease. A type I IFN gene signature generally consists of three groups of IFN-induced genes - those regulated in response to virus-induced type I IFN, those regulated by the IFN-induced mitogen-activated protein kinase/extracellular-regulated kinase (MAPK/ERK pathway, and those by the IFN-induced phosphoinositide-3 kinase (PI-3K pathway. These three groups of type I IFN-regulated genes control important cellular processes such as apoptosis, survival, adhesion, and chemotaxis, that when dysregulated, contribute to autoimmunity. With the recent generation of large datasets in the public domain from next-generation sequencing and DNA microarray experiments, one can perform detailed analyses of cell type-specific gene signatures as well as identify distinct transcription factors that differentially regulate these gene signatures. We have performed bioinformatics analysis of data in the public domain and experimental data from our lab to gain insight into the regulation of type I IFN gene expression. We have found that the genetic landscape of the IFNA and IFNB genes are occupied by transcription factors, such as insulators CTCF and cohesin, that negatively regulate transcription, as well as IRF5 and IRF7, that positively and distinctly regulate IFNA subtypes. A detailed understanding of the factors controlling type I IFN gene transcription will significantly aid in the identification and development of new therapeutic strategies targeting the IFN pathway in autoimmune disease.

  6. TLR2-dependent inhibition of macrophage responses to IFN-gamma is mediated by distinct, gene-specific mechanisms.

    Directory of Open Access Journals (Sweden)

    Sarah A Benson

    2009-07-01

    Full Text Available Mycobacterium tuberculosis uses multiple mechanisms to avoid elimination by the immune system. We have previously shown that M. tuberculosis can inhibit selected macrophage responses to IFN-gamma through TLR2-dependent and -independent mechanisms. To specifically address the role of TLR2 signaling in mediating this inhibition, we stimulated macrophages with the specific TLR2/1 ligand Pam(3CSK(4 and assayed responses to IFN-gamma. Pam(3CSK(4 stimulation prior to IFN-gamma inhibited transcription of the unrelated IFN-gamma-inducible genes, CIITA and CXCL11. Surface expression of MHC class II and secretion of CXCL11 were greatly reduced as well, indicating that the reduction in transcripts had downstream effects. Inhibition of both genes required new protein synthesis. Using chromatin immunoprecipitation, we found that TLR2 stimulation inhibited IFN-gamma-induced RNA polymerase II binding to the CIITA and CXCL11 promoters. Furthermore, TATA binding protein was unable to bind the TATA box of the CXCL11 promoter, suggesting that assembly of transcriptional machinery was disrupted. However, TLR2 stimulation affected chromatin modifications differently at each of the inhibited promoters. Histone H3 and H4 acetylation was reduced at the CIITA promoter but unaffected at the CXCL11 promoter. In addition, NF-kappaB signaling was required for inhibition of CXCL11 transcription, but not for inhibition of CIITA. Taken together, these results indicate that TLR2-dependent inhibition of IFN-gamma-induced gene expression is mediated by distinct, gene-specific mechanisms that disrupt binding of the transcriptional machinery to the promoters.

  7. Deficiency of the AIM2-ASC Signal Uncovers the STING-Driven Overreactive Response of Type I IFN and Reciprocal Depression of Protective IFN-γ Immunity in Mycobacterial Infection.

    Science.gov (United States)

    Yan, Shanshan; Shen, Hongbo; Lian, Qiaoshi; Jin, Wenlong; Zhang, Ronghua; Lin, Xuan; Gu, Wangpeng; Sun, Xiaoyu; Meng, Guangxun; Tian, Zhigang; Chen, Zheng W; Sun, Bing

    2018-02-01

    The nucleic acids of Mycobacterium tuberculosis can be detected by intracellular DNA sensors, such as cyclic GMP-AMP synthase and absent in melanoma 2 (AIM2), which results in the release of type I IFN and the proinflammatory cytokine IL-1β. However, whether cross-talk occurs between AIM2-IL-1β and cyclic GMP-AMP synthase-type I IFN signaling upon M. tuberculosis infection in vivo is unclear. In this article, we demonstrate that mycobacterial infection of AIM2 -/- mice reciprocally induces overreactive IFN-β and depressive IFN-γ responses, leading to higher infection burdens and more severe pathology. We also describe the underlying mechanism whereby activated apoptosis-associated speck-like protein interacts with a key adaptor, known as stimulator of IFN genes (STING), and inhibits the interaction between STING and downstream TANK-binding kinase 1 in bone marrow-derived macrophages and bone marrow-derived dendritic cells, consequently reducing the induction of type I IFN. Of note, apoptosis-associated speck-like protein expression is inversely correlated with IFN-β levels in PBMCs from tuberculosis patients. These data demonstrate that the AIM2-IL-1β signaling pathway negatively regulates the STING-type I IFN signaling pathway by impeding the association between STING and TANK-binding kinase 1, which protects the host from M. tuberculosis infection. This finding has potential clinical significance. Copyright © 2018 by The American Association of Immunologists, Inc.

  8. Duox2-induced innate immune responses in the respiratory epithelium and intranasal delivery of Duox2 DNA using polymer that mediates immunization.

    Science.gov (United States)

    Jeon, Yung Jin; Kim, Hyun Jik

    2018-05-01

    Respiratory mucosa especially nasal epithelium is well known as the first-line barrier of air-borne pathogens. High levels of reactive oxygen species (ROS) are detected in in vitro cultured human epithelial cells and in vivo lung. With identification of NADPH oxidase (Nox) system of respiratory epithelium, the antimicrobial role of ROS has been studied. Duox2 is the most abundant Nox isoform and produces the regulated amount of ROS in respiratory epithelium. Duox2-derived ROS are involved in antiviral innate immune responses but more studies are needed to verify the mechanism. In respiratory epithelium, Duox2-derived ROS is critical for recognition of virus through families retinoic acid-inducible gene-I (RIG-I) and melanoma differentiation-associated protein 5 (MDA5) at the early stage of antiviral innate immune responses. Various secreted interferons (IFNs) play essential roles for antiviral host defense by downstream cell signaling, and transcription of IFN-stimulated genes is started to suppress viral replication. Type I and type III IFNs are verified more responsible for influenza A virus (IAV) infection in respiratory epithelium and Duox2 is required to regulate IFN-related immune responses. Transient overexpression of Duox2 using cationic polymer polyethylenimine (PEI) induces secretion of type I and type III IFNs and significantly attenuated IAV replication in respiratory epithelium. Here, we discuss Duox2-mediated antiviral innate immune responses and the role of Duox2 as a mucosal vaccine to resist respiratory viral infection.

  9. 39th annual Reed rig census

    International Nuclear Information System (INIS)

    Crowhurst, M.E.; Fitts, R.L.

    1991-01-01

    This paper reports on cutbacks in U.S. exploration and development drilling during the first half of 1991 which squeezed most of the optimism out of the drilling industry. Just how rough the year has been is underscored by the results of this year's rig census. The number of rotary rigs available for U.S. drilling declined by only 69 units (3%) during the past 12 months. But despite those withdrawals from competition, only 66% of the remaining rigs were working at the time the census was taken. Results of the 1991 census contrasted sharply with the stability and optimism that seemed apparent a year ago when 72% of the available rig fleet met the census definition of active. At that time, the mini-boom in horizontal drilling coupled with tax-credit- driven gas drilling led to a relatively high rig utilization rate and suggested that rig supply and demand might be close to an economically acceptable balance. However, it quickly became apparent in early 1991 that industry optimism was unjustified. Horizontal drilling began to drop and the lowest natural gas prices in 12 years triggered rapid declines in gas drilling. Although oil prices have been relatively stable and above $18 per bbl since January 1989, most major operators have concluded that a better return on investment can be had outside the U.S. and have drastically cut their domestic drilling budgets. These factors, combined with softened energy demand from the worldwide recession, further slowed U.S. drilling. The long awaited balance between rig supply and demand has seemingly slipped away. The 1991 Reed rig census describes an industry facing several more rough years. Details of this year's census include: The available U.S. fleet now stands at 2,251 rigs, down by 69 from the 2,320-unit total in 1990, and the lowest since 1976. Rigs meeting the census definition of active numbered 1,485, down 192 (11.4%) from the 1,677 active rigs counted a year earlier

  10. The Scaffolding Protein IQGAP1 Interacts with NLRC3 and Inhibits Type I IFN Production.

    Science.gov (United States)

    Tocker, Aaron M; Durocher, Emily; Jacob, Kimberly D; Trieschman, Kate E; Talento, Suzanna M; Rechnitzer, Alma A; Roberts, David M; Davis, Beckley K

    2017-10-15

    Sensing of cytosolic nucleotides is a critical initial step in the elaboration of type I IFN. One of several upstream receptors, cyclic GMP-AMP synthase, binds to cytosolic DNA and generates dicyclic nucleotides that act as secondary messengers. These secondary messengers bind directly to stimulator of IFN genes (STING). STING recruits TNFR-associated NF-κB kinase-binding kinase 1 which acts as a critical node that allows for efficient activation of IFN regulatory factors to drive the antiviral transcriptome. NLRC3 is a recently characterized nucleotide-binding domain, leucine-rich repeat containing protein (NLR) that negatively regulates the type I IFN pathway by inhibiting subcellular redistribution and effective signaling of STING, thus blunting the transcription of type I IFNs. NLRC3 is predominantly expressed in lymphoid and myeloid cells. IQGAP1 was identified as a putative interacting partner of NLRC3 through yeast two-hybrid screening. In this article, we show that IQGAP1 associates with NLRC3 and can disrupt the NLRC3-STING interaction in the cytosol of human epithelial cells. Furthermore, knockdown of IQGAP1 in THP1 and HeLa cells causes significantly more IFN-β production in response to cytosolic nucleic acids. This result phenocopies NLRC3-deficient macrophages and fibroblasts and short hairpin RNA knockdown of NLRC3 in THP1 cells. Our findings suggest that IQGAP1 is a novel regulator of type I IFN production, possibly via interacting with NLRC3 in human monocytic and epithelial cells. Copyright © 2017 by The American Association of Immunologists, Inc.

  11. Nasally administered Lactobacillus rhamnosus strains differentially modulate respiratory antiviral immune responses and induce protection against respiratory syncytial virus infection.

    Science.gov (United States)

    Tomosada, Yohsuke; Chiba, Eriko; Zelaya, Hortensia; Takahashi, Takuya; Tsukida, Kohichiro; Kitazawa, Haruki; Alvarez, Susana; Villena, Julio

    2013-08-15

    Some studies have shown that nasally administered immunobiotics had the potential to improve the outcome of influenza virus infection. However, the capacity of immunobiotics to improve protection against respiratory syncytial virus (RSV) infection was not investigated before. The aims of this study were: a) to evaluate whether the nasal administration of Lactobacillus rhamnosus CRL1505 (Lr05) and L. rhamnosus CRL1506 (Lr06) are able to improve respiratory antiviral defenses and beneficially modulate the immune response triggered by TLR3/RIG-I activation; b) to investigate whether viability of Lr05 or Lr06 is indispensable to modulate respiratory immunity and; c) to evaluate the capacity of Lr05 and Lr06 to improve the resistance of infant mice against RSV infection. Nasally administered Lr05 and Lr06 differentially modulated the TLR3/RIG-I-triggered antiviral respiratory immune response. Lr06 administration significantly modulated the production of IFN-α, IFN-β and IL-6 in the response to poly(I:C) challenge, while nasal priming with Lr05 was more effective to improve levels of IFN-γ and IL-10. Both viable Lr05 and Lr06 strains increased the resistance of infant mice to RSV infection while only heat-killed Lr05 showed a protective effect similar to those observed with viable strains. The present work demonstrated that nasal administration of immunobiotics is able to beneficially modulate the immune response triggered by TLR3/RIG-I activation in the respiratory tract and to increase the resistance of mice to the challenge with RSV. Comparative studies using two Lactobacillus rhamnosus strains of the same origin and with similar technological properties showed that each strain has an specific immunoregulatory effect in the respiratory tract and that they differentially modulate the immune response after poly(I:C) or RSV challenges, conferring different degree of protection and using distinct immune mechanisms. We also demonstrated in this work that it is possible

  12. Hepatitis E virus persists in the presence of a type III interferon response.

    Science.gov (United States)

    Yin, Xin; Li, Xinlei; Ambardekar, Charuta; Hu, Zhimin; Lhomme, Sébastien; Feng, Zongdi

    2017-05-01

    The RIG-I-like RNA helicase (RLR)-mediated interferon (IFN) response plays a pivotal role in the hepatic antiviral immunity. The hepatitis A virus (HAV) and the hepatitis C virus (HCV) counter this response by encoding a viral protease that cleaves the mitochondria antiviral signaling protein (MAVS), a common signaling adaptor for RLRs. However, a third hepatotropic RNA virus, the hepatitis E virus (HEV), does not appear to encode a functional protease yet persists in infected cells. We investigated HEV-induced IFN responses in human hepatoma cells and primary human hepatocytes. HEV infection resulted in persistent virus replication despite poor spread. This was companied by a type III IFN response that upregulated multiple IFN-stimulated genes (ISGs), but type I IFNs were barely detected. Blocking type III IFN production or signaling resulted in reduced ISG expression and enhanced HEV replication. Unlike HAV and HCV, HEV did not cleave MAVS; MAVS protein size, mitochondrial localization, and function remained unaltered in HEV-replicating cells. Depletion of MAVS or MDA5, and to a less extent RIG-I, also diminished IFN production and increased HEV replication. Furthermore, persistent activation of the JAK/STAT signaling rendered infected cells refractory to exogenous IFN treatment, and depletion of MAVS or the receptor for type III IFNs restored the IFN responsiveness. Collectively, these results indicate that unlike other hepatotropic RNA viruses, HEV does not target MAVS and its persistence is associated with continuous production of type III IFNs.

  13. Structural basis for m7G recognition and 2'-O-methyl discrimination in capped RNAs by the innate immune receptor RIG-I

    Energy Technology Data Exchange (ETDEWEB)

    Devarkar, Swapnil C.; Wang, Chen; Miller, Matthew T.; Ramanathan, Anand; Jiang, Fuguo; Khan, Abdul G.; Patel, Smita S.; Marcotrigiano, Joseph

    2016-01-05

    The cytosolic innate immune receptor Retinoic Acid Inducible Gene-I (RIG-I) is the principal detector of pathogenic RNAs carrying a 5'-triphosphate (5'ppp). Self RNAs like mRNAs evade recognition by RIG-I due to posttranscriptional modifications like 5'-end capping with 7-methyl guanosine (m7G) and 2'-O-methylation of 5'-end nucleotides. Viruses have also evolved mechanisms to mimic these modifications, which in part is believed to aid in immune evasion. Currently, it is unclear how these modifications modulate RIG-I recognition. This paper provides structural and mechanistic insights into the roles of the m7G cap and 2'-O-methylation in RIG-I evasion. We show that RIG-I accommodates the m7G base while maintaining the 5'ppp contacts and can recognize Cap-0 RNAs but not Cap-1.

  14. One big rig, two valuable functions

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2004-11-01

    A hybrid coil tubing and conventional workover rig, tailor-made for conditions on Alaska's remote North Slope is described. The dual function rig, owned by BP Exploration, towers 142 feet above the barren Arctic tundra, and weighs between 1.5 and 2 million pounds, rests on eight enormous wheels that stand 11.5 feet tall and 3.5 feet wide, and is supported by 64 smaller tires in between. The rig includes the hybrid coiled tubing rig and a conventional workover rig; it exerts less than 100 pounds per square inch of pressure on the tender Arctic surface as it moves forward at a top speed of two miles per hour. It is considered by its developers as the next-step change in providing cost-effective access to reserves in the large, mature and remote oilfields such as those of Alaska's Prudhoe Bay. The rig is the product of cooperation between Schlumberger expertise in coiled tubing drilling and Nordic-Calista's know-how of jointed pipe operations and operating rigs in an Arctic environment. It is the first time in Prudhoe Bay, and probably in the world, that a coiled tubing unit was installed on a rig to do coiled-tubing sidetracks, i.e to drill a secondary wellbore away from the original wellbore. Since the first unit was commissioned in 1996, the rig has drilled 280 wells. Rig No. 2, much improved and commissioned in 2002, drilled about 30 wells to date. Unlike Rig No, 1, Rig No. 2 can change reels without a crane, and it has a hydraulic pipe skate that moves jointed pipe to and from the rig floor without human aid. The expectation is that using this rig it will be possible to do micro-hole exploration drilling on the North Slope (i.e. drilling a small surface hole with jointed pipe and then switch to coiled tubing), substantially cutting the cost of exploration.

  15. ACTIVATION OF GENES CONTROLLING THE IMMUNE SIGNALING PATHWAYS: DIFFERENTIAL INDIVIDUAL SENSITIVITY OF HUMAN BLOOD CELLS FOR INTERFERON PREPARATIONS AND IFN INDUCERS

    Directory of Open Access Journals (Sweden)

    T. M. Sokolova

    2015-01-01

    Full Text Available We have studied dose effects of several Interferon (IFN inducers, i.e., Genfaxon (beta-1 IFN, Cycloferon and Immunomax upon expression of six genes controlling the signaling in immune pathways (TLR3, TLR4, RIG1, IRF3, IPS, B2M, by means of real-time RT-PCR, being tested with blood cells from three humans. It is revealed that individual cell samples showed different sensitivity to these drugs, probably, due to constitutive levels of TLR3 and TLR4 gene expression and possible connections with their immune pathology. Genfaxon at a dose of 104 ME produced potent stimulation of TLR3, TLR4, IRF3 and B2M genes in two persons. Immunomax, at a dose 0,5 unit, exhibited same effect in one case only (with Epstein-Barr virus infection. Cycloferon stimulated gene expression at much lower levels than Genfaxon in any cases. We have shown a reverse correlation between sensitivity of the cells to Immunomax, and constitutive TLR3 and TLR4 expression. The stimulatory effects of Immunomax were maximal in a person with very low TLR3/4 gene expression. Immunomax boosted the genes from several signaling pathways, including TLR3, TLR4, but genes of RIG/IPS pathway showed higher activation. Cycloferon induced gene transcription of IRF3 and B2M-receptor to higher degree, than expression of TLR3 and TLR4 genes. Hence, our data concerning Genfaxon, Immunomax and Cycloferon confirm their IFN-inducing effects upon human blood cells. The RT-PCR-based evaluation of gene expression related to signaling immune pathways in blood cell populations will enable rapid and highly specific quantitation of IFN and IFN-inducer drugs activities, thus avoiding their biological testing in long-term cell cultures. 

  16. Casein Kinase 1α Mediates the Degradation of Receptors for Type I and Type II Interferons Caused by Hemagglutinin of Influenza A Virus.

    Science.gov (United States)

    Xia, Chuan; Wolf, Jennifer J; Vijayan, Madhuvanthi; Studstill, Caleb J; Ma, Wenjun; Hahm, Bumsuk

    2018-04-01

    Although influenza A virus (IAV) evades cellular defense systems to effectively propagate in the host, the viral immune-evasive mechanisms are incompletely understood. Our recent data showed that hemagglutinin (HA) of IAV induces degradation of type I IFN receptor 1 (IFNAR1). Here, we demonstrate that IAV HA induces degradation of type II IFN (IFN-γ) receptor 1 (IFNGR1), as well as IFNAR1, via casein kinase 1α (CK1α), resulting in the impairment of cellular responsiveness to both type I and II IFNs. IAV infection or transient HA expression induced degradation of both IFNGR1 and IFNAR1, whereas HA gene-deficient IAV failed to downregulate the receptors. IAV HA caused the phosphorylation and ubiquitination of IFNGR1, leading to the lysosome-dependent degradation of IFNGR1. Influenza viral HA strongly decreased cellular sensitivity to type II IFNs, as it suppressed the activation of STAT1 and the induction of IFN-γ-stimulated genes in response to exogenously supplied recombinant IFN-γ. Importantly, CK1α, but not p38 MAP kinase or protein kinase D2, was proven to be critical for HA-induced degradation of both IFNGR1 and IFNAR1. Pharmacologic inhibition of CK1α or small interfering RNA (siRNA)-based knockdown of CK1α repressed the degradation processes of both IFNGR1 and IFNAR1 triggered by IAV infection. Further, CK1α was shown to be pivotal for proficient replication of IAV. Collectively, the results suggest that IAV HA induces degradation of IFN receptors via CK1α, creating conditions favorable for viral propagation. Therefore, the study uncovers a new immune-evasive pathway of influenza virus. IMPORTANCE Influenza A virus (IAV) remains a grave threat to humans, causing seasonal and pandemic influenza. Upon infection, innate and adaptive immunity, such as the interferon (IFN) response, is induced to protect hosts against IAV infection. However, IAV seems to be equipped with tactics to evade the IFN-mediated antiviral responses, although the detailed

  17. RNA-Seq Based Transcriptome Analysis of the Type I Interferon Host Response upon Vaccinia Virus Infection of Mouse Cells

    Directory of Open Access Journals (Sweden)

    Bruno Hernáez

    2017-01-01

    Full Text Available Vaccinia virus (VACV encodes the soluble type I interferon (IFN binding protein B18 that is secreted from infected cells and also attaches to the cell surface, as an immunomodulatory strategy to inhibit the host IFN response. By using next generation sequencing technologies, we performed a detailed RNA-seq study to dissect at the transcriptional level the modulation of the IFN based host response by VACV and B18. Transcriptome profiling of L929 cells after incubation with purified recombinant B18 protein showed that attachment of B18 to the cell surface does not trigger cell signalling leading to transcriptional activation. Consistent with its ability to bind type I IFN, B18 completely inhibited the IFN-mediated modulation of host gene expression. Addition of UV-inactivated virus particles to cell cultures altered the expression of a set of 53 cellular genes, including genes involved in innate immunity. Differential gene expression analyses of cells infected with replication competent VACV identified the activation of a broad range of host genes involved in multiple cellular pathways. Interestingly, we did not detect an IFN-mediated response among the transcriptional changes induced by VACV, even after the addition of IFN to cells infected with a mutant VACV lacking B18. This is consistent with additional viral mechanisms acting at different levels to block IFN responses during VACV infection.

  18. Brucella abortus Triggers a cGAS-Independent STING Pathway To Induce Host Protection That Involves Guanylate-Binding Proteins and Inflammasome Activation.

    Science.gov (United States)

    Costa Franco, Miriam M; Marim, Fernanda; Guimarães, Erika S; Assis, Natan R G; Cerqueira, Daiane M; Alves-Silva, Juliana; Harms, Jerome; Splitter, Gary; Smith, Judith; Kanneganti, Thirumala-Devi; de Queiroz, Nina M G P; Gutman, Delia; Barber, Glen N; Oliveira, Sergio C

    2018-01-15

    Immunity against microbes depends on recognition of pathogen-associated molecular patterns by innate receptors. Signaling pathways triggered by Brucella abortus DNA involves TLR9, AIM2, and stimulator of IFN genes (STING). In this study, we observed by microarray analysis that several type I IFN-associated genes, such as IFN-β and guanylate-binding proteins (GBPs), are downregulated in STING knockout (KO) macrophages infected with Brucella or transfected with DNA. Additionally, we determined that STING and cyclic GMP-AMP synthase (cGAS) are important to engage the type I IFN pathway, but only STING is required to induce IL-1β secretion, caspase-1 activation, and GBP2 and GBP3 expression. Furthermore, we determined that STING but not cGAS is critical for host protection against Brucella infection in macrophages and in vivo. This study provides evidence of a cGAS-independent mechanism of STING-mediated protection against an intracellular bacterial infection. Additionally, infected IFN regulatory factor-1 and IFNAR KO macrophages had reduced GBP2 and GBP3 expression and these cells were more permissive to Brucella replication compared with wild-type control macrophages. Because GBPs are critical to target vacuolar bacteria, we determined whether GBP2 and GBP chr3 affect Brucella control in vivo. GBP chr3 but not GBP2 KO mice were more susceptible to bacterial infection, and small interfering RNA treated-macrophages showed reduction in IL-1β secretion and caspase-1 activation. Finally, we also demonstrated that Brucella DNA colocalizes with AIM2, and AIM2 KO mice are less resistant to B. abortus infection. In conclusion, these findings suggest that the STING-dependent type I IFN pathway is critical for the GBP-mediated release of Brucella DNA into the cytosol and subsequent activation of AIM2. Copyright © 2018 by The American Association of Immunologists, Inc.

  19. Toll-like receptor 7-mediated enhancement of contextual fear memory in mice.

    Science.gov (United States)

    Kubo, Yasunori; Yanagawa, Yoshiki; Matsumoto, Machiko; Hiraide, Sachiko; Kobayashi, Masanobu; Togashi, Hiroko

    2012-10-01

    Toll-like receptor (TLR) 7 recognizes viral single-stranded RNA and triggers production of the type I interferons (IFNs) IFN-α and IFN-β. Imiquimod, a synthetic TLR7 ligand, induces production of type I IFNs and is used clinically as an antiviral and antitumor drug. In the present study, we examined the effect of imiquimod on conditioned and innate fear behaviors in mice. Imiquimod was administered 2, 4, or 15 h before contextual fear conditioning. Imiquimod treatment 4 or 15 h before fear conditioning significantly enhanced context-dependent freezing behavior. This imiquimod-induced enhancement of fear-related behaviors was observed 120 h after fear conditioning. In contrast, imiquimod failed to enhance context-dependent freezing behavior in TLR7 knockout mice. Imiquimod had no significant effect on pain threshold or on innate fear-related behavior, as measured by the elevated plus-maze. The levels of type I IFN mRNA in the brain were significantly increased at 2 h after imiquimod treatment. Imiquimod also increased interleukin (IL)-1β mRNA expression in the brain at 4 h following administration, while mRNA expression of F4/80, a macrophage marker, was unaffected by imiquimod treatment. Our findings suggest that TLR7-mediated signaling enhances contextual fear memory in mice, possibly by inducing the expression of type I IFNs and IL-1β in the brain. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Structural basis for Marburg virus VP35-mediated immune evasion mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Ramanan, Parameshwaran; Edwards, Megan R.; Shabman, Reed S.; Leung, Daisy W.; Endlich-Frazier, Ariel C.; Borek, Dominika M.; Otwinowski, Zbyszek; Liu, Gai; Huh, Juyoung; Basler, Christopher F.; Amarasinghe, Gaya K. [Sinai; (WU-MED); (UTSMC)

    2013-07-22

    Filoviruses, marburgvirus (MARV) and ebolavirus (EBOV), are causative agents of highly lethal hemorrhagic fever in humans. MARV and EBOV share a common genome organization but show important differences in replication complex formation, cell entry, host tropism, transcriptional regulation, and immune evasion. Multifunctional filoviral viral protein (VP) 35 proteins inhibit innate immune responses. Recent studies suggest double-stranded (ds)RNA sequestration is a potential mechanism that allows EBOV VP35 to antagonize retinoic-acid inducible gene-I (RIG-I) like receptors (RLRs) that are activated by viral pathogen–associated molecular patterns (PAMPs), such as double-strandedness and dsRNA blunt ends. Here, we show that MARV VP35 can inhibit IFN production at multiple steps in the signaling pathways downstream of RLRs. The crystal structure of MARV VP35 IID in complex with 18-bp dsRNA reveals that despite the similar protein fold as EBOV VP35 IID, MARV VP35 IID interacts with the dsRNA backbone and not with blunt ends. Functional studies show that MARV VP35 can inhibit dsRNA-dependent RLR activation and interferon (IFN) regulatory factor 3 (IRF3) phosphorylation by IFN kinases TRAF family member-associated NFkb activator (TANK) binding kinase-1 (TBK-1) and IFN kB kinase e (IKKe) in cell-based studies. We also show that MARV VP35 can only inhibit RIG-I and melanoma differentiation associated gene 5 (MDA5) activation by double strandedness of RNA PAMPs (coating backbone) but is unable to inhibit activation of RLRs by dsRNA blunt ends (end capping). In contrast, EBOV VP35 can inhibit activation by both PAMPs. Insights on differential PAMP recognition and inhibition of IFN induction by a similar filoviral VP35 fold, as shown here, reveal the structural and functional plasticity of a highly conserved virulence factor.

  1. Suppression of cancer growth in mice by adeno-associated virus vector-mediated IFN-beta expression driven by hTERT promoter.

    Science.gov (United States)

    He, Ling Feng; Wang, Yi Gang; Xiao, Tian; Zhang, Kang Jiang; Li, Gong Chu; Gu, Jin Fa; Chu, Liang; Tang, Wen Hao; Tan, Wen-Song; Liu, Xin Yuan

    2009-12-28

    Adeno-associated virus (AAV) has rapidly become a promising gene delivery vehicle for its excellent advantages of non-immunogenic, low pathogenicity and long-term gene expression in vivo. However, a major obstacle in development of effective AAV vector is the lack of tissue specificity, which caused low efficiency of AAV transfer to target cells. The application of human telomerase reverse transcriptase (hTERT) promoter is a prior targeting strategy for AAV in cancer gene therapy as hTERT activity is transcriptionally upregulated in most cancer cells. In the present work, we investigated whether AAV-mediated human interferon beta (IFN-beta) gene driven by hTERT promoter could specifically express in tumor cells and suppress tumor cell growth. Our data demonstrated that hTERT promoter-driven IFN-beta expression was the tumor-specific, decreased the cell viability of tumor cells but not normal cells, and induced tumor cell apoptosis via activation of caspase pathway and release of cytochrome c. AAV-mediated IFN-beta expression driven by hTERT promoter significantly suppressed the growth of colorectal cancer and lung cancer xenograft in mice and resulted in tumor cells death in vivo. These data suggested that AAVs in combination with hTERT-mediated IFN-beta expression could exert potential antitumor activity and provide a novel targeting approach to clinical gene therapy of varieties of cancers.

  2. Rig it right! Maya animation rigging concepts

    CERN Document Server

    O'Hailey, Tina

    2013-01-01

    Rigging a character can be a complicated undertaking. Move from a bi-pedal character to a quad- or poly-pedal and, well, things just got real. Where do you begin? Unlike all of those button-pushing manuals out there, Rig it Right! breaks down rigging so that you can achieve a fundamental understanding of the concept, allowing you to rig more intuitively in your own work. Veteran animation professor Tina O'Hailey will get you up and rigging in a matter of hours with step-by-step tutorials covering multiple animation control types, connection methods, interactive skinning, Blend

  3. Overexpression of the transcription factor Sp1 activates the OAS-RNAse L-RIG-I pathway.

    Directory of Open Access Journals (Sweden)

    Valéryane Dupuis-Maurin

    Full Text Available Deregulated expression of oncogenes or transcription factors such as specificity protein 1 (Sp1 is observed in many human cancers and plays a role in tumor maintenance. Paradoxically in untransformed cells, Sp1 overexpression induces late apoptosis but the early intrinsic response is poorly characterized. In the present work, we studied increased Sp1 level consequences in untransformed cells and showed that it turns on an early innate immune transcriptome. Sp1 overexpression does not activate known cellular stress pathways such as DNA damage response or endoplasmic reticulum stress, but induces the activation of the OAS-RNase L pathway and the generation of small self-RNAs, leading to the upregulation of genes of the antiviral RIG-I pathway at the transcriptional and translational levels. Finally, Sp1-induced intrinsic innate immune response leads to the production of the chemokine CXCL4 and to the recruitment of inflammatory cells in vitro and in vivo. Altogether our results showed that increased Sp1 level in untransformed cells constitutes a novel danger signal sensed by the OAS-RNase L axis leading to the activation of the RIG-I pathway. These results suggested that the OAS-RNase L-RIG-I pathway may be activated in sterile condition in absence of pathogen.

  4. Constitutive MHC class I molecules negatively regulate TLR-triggered inflammatory responses via the Fps-SHP-2 pathway.

    Science.gov (United States)

    Xu, Sheng; Liu, Xingguang; Bao, Yan; Zhu, Xuhui; Han, Chaofeng; Zhang, Peng; Zhang, Xuemin; Li, Weihua; Cao, Xuetao

    2012-04-22

    The molecular mechanisms that fine-tune Toll-like receptor (TLR)-triggered innate inflammatory responses remain to be fully elucidated. Major histocompatibility complex (MHC) molecules can mediate reverse signaling and have nonclassical functions. Here we found that constitutively expressed membrane MHC class I molecules attenuated TLR-triggered innate inflammatory responses via reverse signaling, which protected mice from sepsis. The intracellular domain of MHC class I molecules was phosphorylated by the kinase Src after TLR activation, then the tyrosine kinase Fps was recruited via its Src homology 2 domain to phosphorylated MHC class I molecules. This led to enhanced Fps activity and recruitment of the phosphatase SHP-2, which interfered with TLR signaling mediated by the signaling molecule TRAF6. Thus, constitutive MHC class I molecules engage in crosstalk with TLR signaling via the Fps-SHP-2 pathway and control TLR-triggered innate inflammatory responses.

  5. Zika Virus Antagonizes Type I Interferon Responses during Infection of Human Dendritic Cells.

    Directory of Open Access Journals (Sweden)

    James R Bowen

    2017-02-01

    Full Text Available Zika virus (ZIKV is an emerging mosquito-borne flavivirus that is causally linked to severe neonatal birth defects, including microcephaly, and is associated with Guillain-Barre syndrome in adults. Dendritic cells (DCs are an important cell type during infection by multiple mosquito-borne flaviviruses, including dengue virus, West Nile virus, Japanese encephalitis virus, and yellow fever virus. Despite this, the interplay between ZIKV and DCs remains poorly defined. Here, we found human DCs supported productive infection by a contemporary Puerto Rican isolate with considerable variability in viral replication, but not viral binding, between DCs from different donors. Historic isolates from Africa and Asia also infected DCs with distinct viral replication kinetics between strains. African lineage viruses displayed more rapid replication kinetics and infection magnitude as compared to Asian lineage viruses, and uniquely induced cell death. Infection of DCs with both contemporary and historic ZIKV isolates led to minimal up-regulation of T cell co-stimulatory and MHC molecules, along with limited secretion of inflammatory cytokines. Inhibition of type I interferon (IFN protein translation was observed during ZIKV infection, despite strong induction at the RNA transcript level and up-regulation of other host antiviral proteins. Treatment of human DCs with RIG-I agonist potently restricted ZIKV replication, while type I IFN had only modest effects. Mechanistically, we found all strains of ZIKV antagonized type I IFN-mediated phosphorylation of STAT1 and STAT2. Combined, our findings show that ZIKV subverts DC immunogenicity during infection, in part through evasion of type I IFN responses, but that the RLR signaling pathway is still capable of inducing an antiviral state, and therefore may serve as an antiviral therapeutic target.

  6. Vitamin D Is Required for IFN-γ–Mediated Antimicrobial Activity of Human Macrophages

    Science.gov (United States)

    Fabri, Mario; Stenger, Steffen; Shin, Dong-Min; Yuk, Jae-Min; Liu, Philip T.; Realegeno, Susan; Lee, Hye-Mi; Krutzik, Stephan R.; Schenk, Mirjam; Sieling, Peter A.; Teles, Rosane; Montoya, Dennis; Iyer, Shankar S.; Bruns, Heiko; Lewinsohn, David M.; Hollis, Bruce W.; Hewison, Martin; Adams, John S.; Steinmeyer, Andreas; Zügel, Ulrich; Cheng, Genhong; Jo, Eun-Kyeong; Bloom, Barry R.; Modlin, Robert L.

    2012-01-01

    Control of tuberculosis worldwide depends on our understanding of human immune mechanisms, which combat the infection. Acquired T cell responses are critical for host defense against microbial pathogens, yet the mechanisms by which they act in humans remain unclear. We report that T cells, by the release of interferon-γ (IFN-γ), induce autophagy, phagosomal maturation, the production of antimicrobial peptides such as cathelicidin, and antimicrobial activity against Mycobacterium tuberculosis in human macrophages via a vitamin D–dependent pathway. IFN-γ induced the antimicrobial pathway in human macrophages cultured in vitamin D–sufficient sera, but not in sera from African-Americans that have lower amounts of vitamin D and who are more susceptible to tuberculosis. In vitro supplementation of vitamin D–deficient serum with 25-hydroxyvitamin D3 restored IFN-γ–induced antimicrobial peptide expression, autophagy, phagosome-lysosome fusion, and antimicrobial activity. These results suggest a mechanism in which vitamin D is required for acquired immunity to overcome the ability of intracellular pathogens to evade macrophage-mediated antimicrobial responses. The present findings underscore the importance of adequate amounts of vitamin D in all human populations for sustaining both innate and acquired immunity against infection. PMID:21998409

  7. Advancing rig design: latest rig technologies improving efficiency and safety

    Energy Technology Data Exchange (ETDEWEB)

    Greenaway, R.

    1997-12-01

    Recent advances in drilling rig technologies that improve the ways for finding oil and natural gas, and are also solving some safety and transportation problems, have been reviewed. The coiled tubing drilling rig developed by joint venture TransOcean Ensign Drilling Technology was one of the innovations described. It is able to run a three-and-a-quarter inch coiled tubing, the only system capable of doing this in a land-based application. Tesco Corporation`s new casing drilling rig, which is expected to lower the cost of moving the rig, and Brinkerhoff Drilling`s new generation modular (NGM)-rig, claimed to be the most mobile rig in North America, are other new developments worthy of note. Tesco`s casing drilling rig has the potential to reduce drilling costs by as much as 30 to 40 per cent, while the NGM-rig could reduce rig mobilization time by 50 to 80 per cent, and the number of wells drilled by the same rig could increase by 20 per cent, due to the NGM-rig`s versatility and flexibility.

  8. Macrophage-expressed IFN-β contributes to apoptotic alveolar epithelial cell injury in severe influenza virus pneumonia.

    Directory of Open Access Journals (Sweden)

    Katrin Högner

    2013-02-01

    Full Text Available Influenza viruses (IV cause pneumonia in humans with progression to lung failure and fatal outcome. Dysregulated release of cytokines including type I interferons (IFNs has been attributed a crucial role in immune-mediated pulmonary injury during severe IV infection. Using ex vivo and in vivo IV infection models, we demonstrate that alveolar macrophage (AM-expressed IFN-β significantly contributes to IV-induced alveolar epithelial cell (AEC injury by autocrine induction of the pro-apoptotic factor TNF-related apoptosis-inducing ligand (TRAIL. Of note, TRAIL was highly upregulated in and released from AM of patients with pandemic H1N1 IV-induced acute lung injury. Elucidating the cell-specific underlying signalling pathways revealed that IV infection induced IFN-β release in AM in a protein kinase R- (PKR- and NF-κB-dependent way. Bone marrow chimeric mice lacking these signalling mediators in resident and lung-recruited AM and mice subjected to alveolar neutralization of IFN-β and TRAIL displayed reduced alveolar epithelial cell apoptosis and attenuated lung injury during severe IV pneumonia. Together, we demonstrate that macrophage-released type I IFNs, apart from their well-known anti-viral properties, contribute to IV-induced AEC damage and lung injury by autocrine induction of the pro-apoptotic factor TRAIL. Our data suggest that therapeutic targeting of the macrophage IFN-β-TRAIL axis might represent a promising strategy to attenuate IV-induced acute lung injury.

  9. Renal ischemia-reperfusion injury and adenosine 2A receptor-mediated tissue protection: the role of CD4+ T cells and IFN-gamma.

    Science.gov (United States)

    Day, Yuan-Ji; Huang, Liping; Ye, Hong; Li, Li; Linden, Joel; Okusa, Mark D

    2006-03-01

    A(2A) adenosine receptor (A(2A)R)-expressing bone marrow (BM)-derived cells contribute to the renal protective effect of A(2A) agonists in renal ischemia-reperfusion injury (IRI). We performed IRI in mice lacking T and B cells to determine whether A(2A)R expressed in CD4+ cells mediate protection from IRI. Rag-1 knockout (KO) mice were protected in comparison to wild-type (WT) mice when subjected to IRI. ATL146e, a selective A(2A) agonist, did not confer additional protection. IFN-gamma is an important early signal in IRI and is thought to contribute to reperfusion injury. Because IFN-gamma is produced by kidney cells and T cells we performed IRI in BM chimeras in which the BM of WT mice was reconstituted with BM from IFN-gamma KO mice (IFN-gamma KO-->WT chimera). We observed marked reduction in IRI in comparison to WT-->WT chimeras providing additional indirect support for the role of T cells. To confirm the role of CD4+ A(2A)R in mediating protection from IRI, Rag-1 KO mice were subjected to ischemia-reperfusion. The protection observed in Rag-1 KO mice was reversed in Rag-1 KO mice that were adoptively transferred WT CD4+ cells (WT CD4+-->Rag-1 KO) or A(2A) KO CD4+ cells (A(2A) KO CD4+-->Rag-1 KO). ATL146e reduced injury in WT CD4+-->Rag-1 KO mice but not in A(2A) KO CD4+-->Rag-1 KO mice. Rag-1 KO mice reconstituted with CD4+ cells derived from IFN-gamma KO mice (IFN-gamma CD4+-->Rag-1 KO) were protected from IRI; ATL146e conferred no additional protection. These studies demonstrate that CD4+ IFN-gamma contributes to IRI and that A(2A) agonists mediate protection from IRI through action on CD4+ cells.

  10. The histidine transporter SLC15A4 coordinates mTOR-dependent inflammatory responses and pathogenic antibody production.

    Science.gov (United States)

    Kobayashi, Toshihiko; Shimabukuro-Demoto, Shiho; Yoshida-Sugitani, Reiko; Furuyama-Tanaka, Kaori; Karyu, Hitomi; Sugiura, Yuki; Shimizu, Yukiko; Hosaka, Toshiaki; Goto, Motohito; Kato, Norihiro; Okamura, Tadashi; Suematsu, Makoto; Yokoyama, Shigeyuki; Toyama-Sorimachi, Noriko

    2014-09-18

    SLC15A4 is a lysosome-resident, proton-coupled amino-acid transporter that moves histidine and oligopeptides from inside the lysosome to the cytosol of eukaryotic cells. SLC15A4 is required for Toll-like receptor 7 (TLR7)- and TLR9-mediated type I interferon (IFN-I) productions in plasmacytoid dendritic cells (pDCs) and is involved in the pathogenesis of certain diseases including lupus-like autoimmunity. How SLC15A4 contributes to diseases is largely unknown. Here we have shown that B cell SLC15A4 was crucial for TLR7-triggered IFN-I and autoantibody productions in a mouse lupus model. SLC15A4 loss disturbed the endolysosomal pH regulation and probably the v-ATPase integrity, and these changes were associated with disruption of the mTOR pathway, leading to failure of the IFN regulatory factor 7 (IRF7)-IFN-I regulatory circuit. Importantly, SLC15A4's transporter activity was necessary for the TLR-triggered cytokine production. Our findings revealed that SLC15A4-mediated optimization of the endolysosomal state is integral to a TLR7-triggered, mTOR-dependent IRF7-IFN-I circuit that leads to autoantibody production. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Glycosaminoglycans mediate retention of the poxvirus type I interferon binding protein at the cell surface to locally block interferon antiviral responses

    Science.gov (United States)

    Montanuy, Imma; Alejo, Ali; Alcami, Antonio

    2011-01-01

    Eradication of smallpox was accomplished 30 yr ago, but poxviral infections still represent a public health concern due to the potential release of variola virus or the emergence of zoonotic poxviruses, such as monkeypox virus. A critical determinant of poxvirus virulence is the inhibition of interferons (IFNs) by the virus-encoded type I IFN-binding protein (IFNα/βBP). This immunomodulatory protein is secreted and has the unique property of interacting with the cell surface in order to prevent IFN-mediated antiviral responses. However, the mechanism of its attachment to the cell surface remains unknown. Using surface plasmon resonance and cell-binding assays, we report that the IFNα/βBP from vaccinia virus, the smallpox vaccine, interacts with cell surface glycosaminoglycans (GAGs). Analysis of the contribution of different regions of the protein to cell surface binding demonstrated that clusters of basic residues in the first immunoglobulin domain mediate GAG interactions. Furthermore, mutation of the GAG-interaction motifs does not affect its IFN-binding and -blocking capacity. Functional conservation of GAG-binding sites is demonstrated for the IFNα/βBP from variola and monkeypox viruses, extending our understanding of immune modulation by the most virulent human poxviruses. These results are relevant for the design of improved vaccines and intervention strategies.—Montanuy, I., Alejo, A., Alcami, A. Glycosaminoglycans mediate retention of the poxvirus type I interferon binding protein at the cell surface to locally block interferon antiviral responses. PMID:21372110

  12. DDX3 directly regulates TRAF3 ubiquitination and acts as a scaffold to co-ordinate assembly of signalling complexes downstream from MAVS.

    Science.gov (United States)

    Gu, Lili; Fullam, Anthony; McCormack, Niamh; Höhn, Yvette; Schröder, Martina

    2017-02-15

    The human DEAD-box helicase 3 (DDX3) has been shown to contribute to type I interferon (IFN) induction downstream from antiviral pattern recognition receptors. It binds to TANK-binding kinase 1 and IκB-kinase-ε (IKKε), the two key kinases mediating activation of IFN regulatory factor (IRF) 3 and IRF7. We previously demonstrated that DDX3 facilitates IKKε activation downstream from RIG-I and then links the activated kinase to IRF3. In the present study, we probed the interactions between DDX3 and other key signalling molecules in the RIG-I pathway and identified a novel direct interaction between DDX3 and TNF receptor-associated factor 3 (TRAF3) mediated by a TRAF-interaction motif in the N-terminus of DDX3, which was required for TRAF3 ubiquitination. Interestingly, we observed two waves of K63-linked TRAF3 ubiquitination following RIG-I activation by Sendai virus (SeV) infection, both of which were suppressed by DDX3 knockdown. We also investigated the spatiotemporal formation of endogenous downstream signalling complexes containing the mitochondrial antiviral signalling (MAVS) adaptor, DDX3, IκB-kinase-ε (IKKε), TRAF3 and IRF3. DDX3 was recruited to MAVS early after SeV infection, suggesting that it might mediate subsequent recruitment of other molecules. Indeed, knockdown of DDX3 prevented the formation of TRAF3-MAVS and TRAF3-IKKε complexes. Based on our data, we propose that early TRAF3 ubiquitination is required for the formation of a stable MAVS-TRAF3 complex, while the second wave of TRAF3 ubiquitination mediates IRF3 recruitment and activation. Our study characterises DDX3 as a multifunctional adaptor molecule that co-ordinates assembly of different TRAF3, IKKε and IRF3-containing signalling complexes downstream from MAVS. Additionally, it provides novel insights into the role of TRAF3 in RIG-I signalling. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  13. Akt Kinase-Mediated Checkpoint of cGAS DNA Sensing Pathway

    Directory of Open Access Journals (Sweden)

    Gil Ju Seo

    2015-10-01

    Full Text Available Upon DNA stimulation, cyclic GMP-AMP synthase (cGAS synthesizes the second messenger cyclic GMP-AMP (cGAMP that binds to the STING, triggering antiviral interferon-β (IFN-β production. However, it has remained undetermined how hosts regulate cGAS enzymatic activity after the resolution of DNA immunogen. Here, we show that Akt kinase plays a negative role in cGAS-mediated anti-viral immune response. Akt phosphorylated the S291 or S305 residue of the enzymatic domain of mouse or human cGAS, respectively, and this phosphorylation robustly suppressed its enzymatic activity. Consequently, expression of activated Akt led to the reduction of cGAMP and IFN-β production and the increase of herpes simplex virus 1 replication, whereas treatment with Akt inhibitor augmented cGAS-mediated IFN-β production. Furthermore, expression of the phosphorylation-resistant cGAS S291A mutant enhanced IFN-β production upon DNA stimulation, HSV-1 infection, and vaccinia virus infection. Our study identifies an Akt kinase-mediated checkpoint to fine-tune hosts’ immune responses to DNA stimulation.

  14. Topoisomerase II Inhibitors Induce DNA Damage-Dependent Interferon Responses Circumventing Ebola Virus Immune Evasion

    Directory of Open Access Journals (Sweden)

    Priya Luthra

    2017-04-01

    Full Text Available Ebola virus (EBOV protein VP35 inhibits production of interferon alpha/beta (IFN by blocking RIG-I-like receptor signaling pathways, thereby promoting virus replication and pathogenesis. A high-throughput screening assay, developed to identify compounds that either inhibit or bypass VP35 IFN-antagonist function, identified five DNA intercalators as reproducible hits from a library of bioactive compounds. Four, including doxorubicin and daunorubicin, are anthracycline antibiotics that inhibit topoisomerase II and are used clinically as chemotherapeutic drugs. These compounds were demonstrated to induce IFN responses in an ATM kinase-dependent manner and to also trigger the DNA-sensing cGAS-STING pathway of IFN induction. These compounds also suppress EBOV replication in vitro and induce IFN in the presence of IFN-antagonist proteins from multiple negative-sense RNA viruses. These findings provide new insights into signaling pathways activated by important chemotherapy drugs and identify a novel therapeutic approach for IFN induction that may be exploited to inhibit RNA virus replication.

  15. Functional characterization of duck LSm14A in IFN-β induction.

    Science.gov (United States)

    Hua, Kexin; Li, Huilin; Chen, Huanchun; Foda, Mohamed Frahat; Luo, Rui; Jin, Hui

    2017-11-01

    Human LSm14A is a key component of processing body (P-body) assembly that mediates interferon-β (IFN-β) production by sensing viral RNA or DNA. To the best of our knowledge, we are the first to report duck LSm14A (duLSm14A) cloning from duck embryo fibroblasts (DEFs). Full-length duLSm14A encoded 461 amino acids and was highly homologous with chicken and swan goose sequences. More interestingly, the duLSm14A mRNA was extensively expressed in all the studied tissues. In DEFs, duLSm14A was localized in the cytoplasm as P-body-like dots. Expression of duLSm14A induced IFN-β through the activation of interferon regulatory factor-1 and nuclear factor-κB in DEFs. Furthermore, knockdown of duLSm14A by small interfering RNA notably decreased poly(I:C)- or duck reovirus-induced IFN-β production. The present study results indicate that the duLSm14A is an essential sensor that mediates duck innate immunity against viral infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. KAP1 regulates type I interferon/STAT1-mediated IRF-1 gene expression

    International Nuclear Information System (INIS)

    Kamitani, Shinya; Ohbayashi, Norihiko; Ikeda, Osamu; Togi, Sumihito; Muromoto, Ryuta; Sekine, Yuichi; Ohta, Kazuhide; Ishiyama, Hironobu; Matsuda, Tadashi

    2008-01-01

    Signal transducers and activators of transcription (STATs) mediate cell proliferation, differentiation, and survival in immune responses, hematopoiesis, neurogenesis, and other biological processes. Recently, we showed that KAP1 is a novel STAT-binding partner that regulates STAT3-mediated transactivation. KAP1 is a universal co-repressor protein for the KRAB zinc finger protein superfamily of transcriptional repressors. In this study, we found KAP1-dependent repression of interferon (IFN)/STAT1-mediated signaling. We also demonstrated that endogenous KAP1 associates with endogenous STAT1 in vivo. Importantly, a small-interfering RNA-mediated reduction in KAP1 expression enhanced IFN-induced STAT1-dependent IRF-1 gene expression. These results indicate that KAP1 may act as an endogenous regulator of the IFN/STAT1 signaling pathway

  17. IL-15 Superagonist–Mediated Immunotoxicity: Role of NK Cells and IFN

    Science.gov (United States)

    Guo, Yin; Luan, Liming; Rabacal, Whitney; Bohannon, Julia K.; Fensterheim, Benjamin A.; Hernandez, Antonio

    2015-01-01

    IL-15 is currently undergoing clinical trials to assess its efficacy for treatment of advanced cancers. The combination of IL-15 with soluble IL-15Rα generates a complex termed IL-15 superagonist (IL-15 SA) that possesses greater biological activity than IL-15 alone. IL-15 SA is considered an attractive antitumor and antiviral agent because of its ability to selectively expand NK and memory CD8+ T (mCD8+ T) lymphocytes. However, the adverse consequences of IL-15 SA treatment have not been defined. In this study, the effect of IL-15 SA on physiologic and immunologic functions of mice was evaluated. IL-15 SA caused dose- and time-dependent hypothermia, weight loss, liver injury, and mortality. NK (especially the proinflammatory NK subset), NKT, and mCD8+ T cells were preferentially expanded in spleen and liver upon IL-15 SA treatment. IL-15 SA caused NK cell activation as indicated by increased CD69 expression and IFN-γ, perforin, and granzyme B production, whereas NKT and mCD8+ T cells showed minimal, if any, activation. Cell depletion and adoptive transfer studies showed that the systemic toxicity of IL-15 SA was mediated by hyperproliferation of activated NK cells. Production of the proinflammatory cytokine IFN-γ, but not TNF-α or perforin, was essential to IL-15 SA–induced immunotoxicity. The toxicity and immunological alterations shown in this study are comparable to those reported in recent clinical trials of IL-15 in patients with refractory cancers and advance current knowledge by providing mechanistic insights into IL-15 SA–mediated immunotoxicity. PMID:26216888

  18. cGAS Senses Human Cytomegalovirus and Induces Type I Interferon Responses in Human Monocyte-Derived Cells.

    Directory of Open Access Journals (Sweden)

    Jennifer Paijo

    2016-04-01

    Full Text Available Human cytomegalovirus (HCMV infections of healthy individuals are mostly unnoticed and result in viral latency. However, HCMV can also cause devastating disease, e.g., upon reactivation in immunocompromised patients. Yet, little is known about human immune cell sensing of DNA-encoded HCMV. Recent studies indicated that during viral infection the cyclic GMP/AMP synthase (cGAS senses cytosolic DNA and catalyzes formation of the cyclic di-nucleotide cGAMP, which triggers stimulator of interferon genes (STING and thus induces antiviral type I interferon (IFN-I responses. We found that plasmacytoid dendritic cells (pDC as well as monocyte-derived DC and macrophages constitutively expressed cGAS and STING. HCMV infection further induced cGAS, whereas STING expression was only moderately affected. Although pDC expressed particularly high levels of cGAS, and the cGAS/STING axis was functional down-stream of STING, as indicated by IFN-I induction upon synthetic cGAMP treatment, pDC were not susceptible to HCMV infection and mounted IFN-I responses in a TLR9-dependent manner. Conversely, HCMV infected monocyte-derived cells synthesized abundant cGAMP levels that preceded IFN-I production and that correlated with the extent of infection. CRISPR/Cas9- or siRNA-mediated cGAS ablation in monocytic THP-1 cells and primary monocyte-derived cells, respectively, impeded induction of IFN-I responses following HCMV infection. Thus, cGAS is a key sensor of HCMV for IFN-I induction in primary human monocyte-derived DC and macrophages.

  19. Independent, parallel pathways to CXCL10 induction in HCV-infected hepatocytes.

    Science.gov (United States)

    Brownell, Jessica; Wagoner, Jessica; Lovelace, Erica S; Thirstrup, Derek; Mohar, Isaac; Smith, Wesley; Giugliano, Silvia; Li, Kui; Crispe, I Nicholas; Rosen, Hugo R; Polyak, Stephen J

    2013-10-01

    The pro-inflammatory chemokine CXCL10 is induced by HCV infection in vitro and in vivo, and is associated with outcome of IFN (interferon)-based therapy. We studied how hepatocyte sensing of early HCV infection via TLR3 (Toll-like receptor 3) and RIG-I (retinoic acid inducible gene I) led to expression of CXCL10. CXCL10, type I IFN, and type III IFN mRNAs and proteins were measured in PHH (primary human hepatocytes) and hepatocyte lines harboring functional or non-functional TLR3 and RIG-I pathways following HCV infection or exposure to receptor-specific stimuli. HuH7 human hepatoma cells expressing both TLR3 and RIG-I produced maximal CXCL10 during early HCV infection. Neutralization of type I and type III IFNs had no impact on virus-induced CXCL10 expression in TLR3+/RIG-I+ HuH7 cells, but reduced CXCL10 expression in PHH. PHH cultures were positive for monocyte, macrophage, and dendritic cell mRNAs. Immunodepletion of non-parenchymal cells (NPCs) eliminated marker expression in PHH cultures, which then showed no IFN requirement for CXCL10 induction during HCV infection. Immunofluorescence studies also revealed a positive correlation between intracellular HCV Core and CXCL10 protein expression (r(2) = 0.88, p ≤ 0.001). While CXCL10 induction in hepatocytes during the initial phase of HCV infection is independent of hepatocyte-derived type I and type III IFNs, NPC-derived IFNs contribute to CXCL10 induction during HCV infection in PHH cultures. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  20. Co-incubation with IL-18 potentiates antigen-specific IFN-γ response in a whole-blood stimulation assay for measurement of cell-mediated immune responses in pigs experimentally infected with Lawsonia intracellularis

    DEFF Research Database (Denmark)

    Riber, Ulla; Boesen, Henriette Toft; Jakobsen, Jeanne Toft

    2011-01-01

    The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult to evalu......The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult...

  1. Viral Inhibition of PRR-Mediated Innate Immune Response: Learning from KSHV Evasion Strategies.

    Science.gov (United States)

    Lee, Hye-Ra; Choi, Un Yung; Hwang, Sung-Woo; Kim, Stephanie; Jung, Jae U

    2016-11-30

    The innate immune system has evolved to detect and destroy invading pathogens before they can establish systemic infection. To successfully eradicate pathogens, including viruses, host innate immunity is activated through diverse pattern recognition receptors (PRRs) which detect conserved viral signatures and trigger the production of type I interferon (IFN) and pro-inflammatory cytokines to mediate viral clearance. Viral persistence requires that viruses co-opt cellular pathways and activities for their benefit. In particular, due to the potent antiviral activities of IFN and cytokines, viruses have developed various strategies to meticulously modulate intracellular innate immune sensing mechanisms to facilitate efficient viral replication and persistence. In this review, we highlight recent advances in the study of viral immune evasion strategies with a specific focus on how Kaposi's sarcoma-associated herpesvirus (KSHV) effectively targets host PRR signaling pathways.

  2. PRMT5-Mediated Methylation of NF-κB p65 at Arg174 Is Required for Endothelial CXCL11 Gene Induction in Response to TNF-α and IFN-γ Costimulation.

    Directory of Open Access Journals (Sweden)

    Daniel P Harris

    Full Text Available Inflammatory agonists differentially activate gene expression of the chemokine family of proteins in endothelial cells (EC. TNF is a weak inducer of the chemokine CXCL11, while TNF and IFN-γ costimulation results in potent CXCL11 induction. The molecular mechanisms underlying TNF plus IFN-γ-mediated CXCL11 induction are not fully understood. We have previously reported that the protein arginine methyltransferase PRMT5 catalyzes symmetrical dimethylation of the NF-κB subunit p65 in EC at multiple arginine residues. Methylation of Arg30 and Arg35 on p65 is critical for TNF induction of CXCL10 in EC. Here we show that PRMT5-mediated methylation of p65 at Arg174 is required for induction of CXCL11 when EC are costimulated with TNF and IFN-γ. Knockdown of PRMT5 by RNAi reduced CXCL11 mRNA and protein levels in costimulated cells. Reconstitution of p65 Arg174Ala or Arg174Lys mutants into EC that were depleted of endogenous p65 blunted TNF plus IFN-γ-mediated CXCL11 induction. Mass spectrometric analyses showed that p65 Arg174 arginine methylation is enhanced by TNF plus IFN-γ costimulation, and is catalyzed by PRMT5. Chromatin immunoprecipitation assays (ChIP demonstrated that PRMT5 is necessary for p65 association with the CXCL11 promoter in response to TNF plus IFN-γ. Further, reconstitution of p65 Arg174Lys mutant in EC abrogated this p65 association with the CXCL11 promoter. Finally, ChIP and Re-ChIP assays revealed that symmetrical dimethylarginine-containing proteins complexed with the CXCL11 promoter were diminished in p65 Arg174Lys-reconstituted EC stimulated with TNF and IFN-γ. In total, these results indicate that PRMT5-mediated p65 methylation at Arg174 is essential for TNF plus IFN-γ-mediated CXCL11 gene induction. We therefore suggest that the use of recently developed small molecule inhibitors of PRMT5 may present a therapeutic approach to moderating chronic inflammatory pathologies.

  3. Hoisting and Rigging (Formerly Hoisting and Rigging Manual)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    This standard is intended as a reference document to be used by supervisors, line managers, safety personnel, equipment operators, and any other personnel responsible for safety of hoisting and rigging operations at DOE sites. It quotes or paraphrases the US OSHA and ANSI requirements. It also encompasses, under one cover,hoisting and rigging requirements, codes, standards, and regulations, eliminating the need to maintain extensive (and often incomplete) libraries of hoisting and rigging standards throughout DOE. The standard occasionally goes beyond the minimum general industry standards established by OSHA and ANSI, and also delineates the more stringent requirements necessary to accomplish the complex, diversified, critical, and often hazardous hoisting and rigging work found with the DOE complex.

  4. Akt Kinase-Mediated Checkpoint of cGAS DNA Sensing Pathway.

    Science.gov (United States)

    Seo, Gil Ju; Yang, Aerin; Tan, Brandon; Kim, Sungyoon; Liang, Qiming; Choi, Younho; Yuan, Weiming; Feng, Pinghui; Park, Hee-Sung; Jung, Jae U

    2015-10-13

    Upon DNA stimulation, cyclic GMP-AMP synthase (cGAS) synthesizes the second messenger cyclic GMP-AMP (cGAMP) that binds to the STING, triggering antiviral interferon-β (IFN-β) production. However, it has remained undetermined how hosts regulate cGAS enzymatic activity after the resolution of DNA immunogen. Here, we show that Akt kinase plays a negative role in cGAS-mediated anti-viral immune response. Akt phosphorylated the S291 or S305 residue of the enzymatic domain of mouse or human cGAS, respectively, and this phosphorylation robustly suppressed its enzymatic activity. Consequently, expression of activated Akt led to the reduction of cGAMP and IFN-β production and the increase of herpes simplex virus 1 replication, whereas treatment with Akt inhibitor augmented cGAS-mediated IFN-β production. Furthermore, expression of the phosphorylation-resistant cGAS S291A mutant enhanced IFN-β production upon DNA stimulation, HSV-1 infection, and vaccinia virus infection. Our study identifies an Akt kinase-mediated checkpoint to fine-tune hosts' immune responses to DNA stimulation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Heartland virus NSs protein disrupts host defenses by blocking the TBK1 kinase-IRF3 transcription factor interaction and signaling required for interferon induction.

    Science.gov (United States)

    Ning, Yun-Jia; Feng, Kuan; Min, Yuan-Qin; Deng, Fei; Hu, Zhihong; Wang, Hualin

    2017-10-06

    Heartland virus (HRTV) is a pathogenic phlebovirus related to the severe fever with thrombocytopenia syndrome virus (SFTSV), another phlebovirus causing life-threatening disease in humans. Previous findings have suggested that SFTSV can antagonize the host interferon (IFN) system via viral nonstructural protein (NSs)-mediated sequestration of antiviral signaling proteins into NSs-induced inclusion bodies. However, whether and how HRTV counteracts the host innate immunity is unknown. Here, we report that HRTV NSs (HNSs) also antagonizes IFN and cytokine induction and bolsters viral replication, although no noticeable inclusion body formation was observed in HNSs-expressing cells. Furthermore, HNSs inhibited the virus-triggered activation of IFN-β promoter by specifically targeting the IFN-stimulated response element but not the NF-κB response element. Consistently, HNSs blocked the phosphorylation and nuclear translocation of IFN regulatory factor 3 (IRF3, an IFN-stimulated response element-activating transcription factor). Reporter gene assays next showed that HNSs blockades the antiviral signaling mediated by RIG-I-like receptors likely at the level of TANK-binding kinase 1 (TBK1). Indeed, HNSs strongly interacts with TBK1 as indicated by confocal microscopy and pulldown analyses, and we also noted that the scaffold dimerization domain of TBK1 is required for the TBK1-HNSs interaction. Finally, pulldown assays demonstrated that HNSs expression dose-dependently diminishes a TBK1-IRF3 interaction, further explaining the mechanism for HNSs function. Collectively, these data suggest that HNSs, an antagonist of host innate immunity, interacts with TBK1 and thereby hinders the association of TBK1 with its substrate IRF3, thus blocking IRF3 activation and transcriptional induction of the cellular antiviral responses. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. IL-18 potentiated whole blood IFN-γ assay can identify cell-mediated immune responses towards Lawsonia intracellularis in experimentally infected pigs

    DEFF Research Database (Denmark)

    Riber, Ulla; Jakobsen, Jeanne Toft; Hvass, Henriette Cordes

    Lawsonia intracellularis is an obligate intracellular bacteria causing proliferative enteropathy (PE) in pigs. The infection causes diarrhoea, retarded growth and sudden death in pigs and is one of the most economically important diseases in the swine industry worldwide. The infection is one...... indications that cell-mediated immune responses (CMI) are important for the protection against infections with L. intracellularis and in mice models IFN-γ has been shown to play a key role in the host defence against experimental infections . In L. intracellularis infected pigs, IFN-γ is only sparsely...

  7. Understanding Rig Rates

    OpenAIRE

    Petter Osmundsen; Knut Einar Rosendahl; Terje Skjerpen

    2013-01-01

    We examine the largest cost component in offshore development projects, drilling rates, which have been high over the last years. To our knowledge, rig rates have not been analysed empirically before in the economic literature. By econometric analysis we examine the effects on Gulf of Mexico rig rates of gas and oil prices, rig capacity utilization, contract length and lead time, and rig specific characteristics. Having access to a unique data set containing contract information, we are able ...

  8. Prevention of bone marrow cell apoptosis and regulation of hematopoiesis by type I IFNs during systemic responses to pneumocystis lung infection.

    Science.gov (United States)

    Taylor, David; Wilkison, Michelle; Voyich, Jovanka; Meissner, Nicole

    2011-05-15

    We recently demonstrated that lack of type I IFN signaling (IFNAR knockout) in lymphocyte-deficient mice (IFrag(-/-)) results in bone marrow (BM) failure after Pneumocystis lung infection, whereas lymphocyte-deficient mice with intact IFNAR (RAG(-/-)) had normal hematopoiesis. In the current work, we performed studies to define further the mechanisms involved in the induction of BM failure in this system. BM chimera experiments revealed that IFNAR expression was required on BM-derived but not stroma-derived cells to prevent BM failure. Signals elicited after day 7 postinfection appeared critical in determining BM cell fate. We observed caspase-8- and caspase-9-mediated apoptotic cell death, beginning with neutrophils. Death of myeloid precursors was associated with secondary oxidative stress, and decreasing colony-forming activity in BM cell cultures. Treatment with N-acetylcysteine could slow the progression of, but not prevent, BM failure. Type I IFN signaling has previously been shown to expand the neutrophil life span and regulate the expression of some antiapoptotic factors. Quantitative RT-PCR demonstrated reduced mRNA abundance for the antiapoptotic factors BCL-2, IAP2, MCL-1, and others in BM cells from IFrag(-/-) compared with that in BM cells from RAG(-/-) mice at day 7. mRNA and protein for the proapoptotic cytokine TNF-α was increased, whereas mRNA for the growth factors G-CSF and GM-CSF was reduced. In vivo anti-TNF-α treatment improved precursor cell survival and activity in culture. Thus, we propose that lack of type I IFN signaling results in decreased resistance to inflammation-induced proapoptotic stressors and impaired replenishment by precursors after systemic responses to Pneumocystis lung infection. Our finding may have implications in understanding mechanisms underlying regenerative BM depression/failure during complex immune deficiencies such as AIDS.

  9. Interdependent and independent roles of type I interferons and IL-6 in innate immune, neuroinflammatory and sickness behaviour responses to systemic poly I:C.

    Science.gov (United States)

    Murray, Carol; Griffin, Éadaoin W; O'Loughlin, Elaine; Lyons, Aoife; Sherwin, Eoin; Ahmed, Suaad; Stevenson, Nigel J; Harkin, Andrew; Cunningham, Colm

    2015-08-01

    Type I interferons (IFN-I) are expressed in the brain during many inflammatory and neurodegenerative conditions and have multiple effects on CNS function. IFN-I is readily induced in the brain by systemic administration of the viral mimetic, poly I:C (synthetic double-stranded RNA). We hypothesised that IFN-I contributes to systemically administered poly I:C-induced sickness behaviour, metabolic and neuroinflammatory changes. IFN-I receptor 1 deficient mice (IFNAR1(-/-)) displayed significantly attenuated poly I:C-induced hypothermia, hypoactivity and weight loss compared to WT C57BL/6 mice. This amelioration of sickness was associated with equivalent IL-1β and TNF-α responses but much reduced IL-6 responses in plasma, hypothalamus and hippocampus of IFNAR1(-/-) mice. IFN-β injection induced trivial IL-6 production and limited behavioural change and the poly I:C-induced IFN-β response did not preceed, and would not appear to mediate, IL-6 induction. Rather, IFNAR1(-/-) mice lack basal IFN-I activity, have lower STAT1 levels and show significantly lower levels of several inflammatory transcripts, including stat1. Basal IFN-I activity appears to play a facilitatory role in the full expression of the IL-6 response and activation of the tryptophan-kynurenine metabolism pathway. The deficient IL-6 response in IFNAR1(-/-) mice partially explains the observed incomplete sickness behaviour response. Reconstitution of circulating IL-6 revealed that the role of IFNAR in burrowing activity is mediated via IL-6, while IFN-I and IL-6 have additive effects on hypoactivity, but the role of IFN-I in anorexia is independent of IL-6. Hence, we have demonstrated both interdependent and independent roles for IFN-I and IL-6 in systemic inflammation-induced changes in brain function. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  10. The Ebola virus VP35 protein binds viral immunostimulatory and host RNAs identified through deep sequencing.

    Directory of Open Access Journals (Sweden)

    Kari A Dilley

    Full Text Available Ebola virus and Marburg virus are members of the Filovirdae family and causative agents of hemorrhagic fever with high fatality rates in humans. Filovirus virulence is partially attributed to the VP35 protein, a well-characterized inhibitor of the RIG-I-like receptor pathway that triggers the antiviral interferon (IFN response. Prior work demonstrates the ability of VP35 to block potent RIG-I activators, such as Sendai virus (SeV, and this IFN-antagonist activity is directly correlated with its ability to bind RNA. Several structural studies demonstrate that VP35 binds short synthetic dsRNAs; yet, there are no data that identify viral immunostimulatory RNAs (isRNA or host RNAs bound to VP35 in cells. Utilizing a SeV infection model, we demonstrate that both viral isRNA and host RNAs are bound to Ebola and Marburg VP35s in cells. By deep sequencing the purified VP35-bound RNA, we identified the SeV copy-back defective interfering (DI RNA, previously identified as a robust RIG-I activator, as the isRNA bound by multiple filovirus VP35 proteins, including the VP35 protein from the West African outbreak strain (Makona EBOV. Moreover, RNAs isolated from a VP35 RNA-binding mutant were not immunostimulatory and did not include the SeV DI RNA. Strikingly, an analysis of host RNAs bound by wild-type, but not mutant, VP35 revealed that select host RNAs are preferentially bound by VP35 in cell culture. Taken together, these data support a model in which VP35 sequesters isRNA in virus-infected cells to avert RIG-I like receptor (RLR activation.

  11. The Ebola virus VP35 protein binds viral immunostimulatory and host RNAs identified through deep sequencing.

    Science.gov (United States)

    Dilley, Kari A; Voorhies, Alexander A; Luthra, Priya; Puri, Vinita; Stockwell, Timothy B; Lorenzi, Hernan; Basler, Christopher F; Shabman, Reed S

    2017-01-01

    Ebola virus and Marburg virus are members of the Filovirdae family and causative agents of hemorrhagic fever with high fatality rates in humans. Filovirus virulence is partially attributed to the VP35 protein, a well-characterized inhibitor of the RIG-I-like receptor pathway that triggers the antiviral interferon (IFN) response. Prior work demonstrates the ability of VP35 to block potent RIG-I activators, such as Sendai virus (SeV), and this IFN-antagonist activity is directly correlated with its ability to bind RNA. Several structural studies demonstrate that VP35 binds short synthetic dsRNAs; yet, there are no data that identify viral immunostimulatory RNAs (isRNA) or host RNAs bound to VP35 in cells. Utilizing a SeV infection model, we demonstrate that both viral isRNA and host RNAs are bound to Ebola and Marburg VP35s in cells. By deep sequencing the purified VP35-bound RNA, we identified the SeV copy-back defective interfering (DI) RNA, previously identified as a robust RIG-I activator, as the isRNA bound by multiple filovirus VP35 proteins, including the VP35 protein from the West African outbreak strain (Makona EBOV). Moreover, RNAs isolated from a VP35 RNA-binding mutant were not immunostimulatory and did not include the SeV DI RNA. Strikingly, an analysis of host RNAs bound by wild-type, but not mutant, VP35 revealed that select host RNAs are preferentially bound by VP35 in cell culture. Taken together, these data support a model in which VP35 sequesters isRNA in virus-infected cells to avert RIG-I like receptor (RLR) activation.

  12. Herpes simplex virus infection is sensed by both Toll-like receptors and retinoic acid-inducible gene- like receptors, which synergize to induce type I interferon production

    DEFF Research Database (Denmark)

    Rasmussen, Simon B; Jensen, Søren B; Nielsen, Christoffer

    2009-01-01

    The innate antiviral response is initiated by pattern recognition receptors, which recognize viral pathogen-associated molecular patterns. Here we show that retinoic acid-inducible gene (RIG)-I-like receptors (RLRs) in cooperation with Toll-like receptor (TLR) 9 is required for expression of type I...... interferons (IFNs) after infection with herpes simplex virus (HSV). Our work also identified RNase L as a critical component in IFN induction. Moreover, we found that TLR9 and RLRs activate distinct, as well as overlapping, intracellular signalling pathways. Thus, RLRs are important for recognition of HSV...

  13. Targeting the cytosolic innate immune receptors RIG-I and MDA5 effectively counteracts cancer cell heterogeneity in glioblastoma.

    Science.gov (United States)

    Glas, Martin; Coch, Christoph; Trageser, Daniel; Dassler, Juliane; Simon, Matthias; Koch, Philipp; Mertens, Jerome; Quandel, Tamara; Gorris, Raphaela; Reinartz, Roman; Wieland, Anja; Von Lehe, Marec; Pusch, Annette; Roy, Kristin; Schlee, Martin; Neumann, Harald; Fimmers, Rolf; Herrlinger, Ulrich; Brüstle, Oliver; Hartmann, Gunther; Besch, Robert; Scheffler, Björn

    2013-06-01

    Cellular heterogeneity, for example, the intratumoral coexistence of cancer cells with and without stem cell characteristics, represents a potential root of therapeutic resistance and a significant challenge for modern drug development in glioblastoma (GBM). We propose here that activation of the innate immune system by stimulation of innate immune receptors involved in antiviral and antitumor responses can similarly target different malignant populations of glioma cells. We used short-term expanded patient-specific primary human GBM cells to study the stimulation of the cytosolic nucleic acid receptors melanoma differentiation-associated gene 5 (MDA5) and retinoic acid-inducible gene I (RIG-I). Specifically, we analyzed cells from the tumor core versus "residual GBM cells" derived from the tumor resection margin as well as stem cell-enriched primary cultures versus specimens without stem cell properties. A portfolio of human, nontumor neural cells was used as a control for these studies. The expression of RIG-I and MDA5 could be induced in all of these cells. Receptor stimulation with their respective ligands, p(I:C) and 3pRNA, led to in vitro evidence for an effective activation of the innate immune system. Most intriguingly, all investigated cancer cell populations additionally responded with a pronounced induction of apoptotic signaling cascades revealing a second, direct mechanism of antitumor activity. By contrast, p(I:C) and 3pRNA induced only little toxicity in human nonmalignant neural cells. Granted that the challenge of effective central nervous system (CNS) delivery can be overcome, targeting of RIG-I and MDA5 could thus become a quintessential strategy to encounter heterogeneous cancers in the sophisticated environments of the brain. Copyright © 2013 AlphaMed Press.

  14. Differential expression of viral PAMP receptors mRNA in peripheral blood of patients with chronic hepatitis C infection

    Directory of Open Access Journals (Sweden)

    Riñón Marta

    2007-11-01

    Full Text Available Abstract Background Pathogen-associated molecular patterns (PAMP receptors play a key role in the early host response to viruses. In this work, we determined mRNA levels of two members of the Toll-like Receptors family, (TLR3 and TLR7 and the helicase RIG-I, all of three recognizing viral RNA products, in peripheral blood of healthy donors and hepatitis C virus (HCV patients, to observe if their transcripts are altered in this disease. Methods IFN-α, TLR3, TLR7 and RIG-I levels in peripheral blood from healthy controls (n = 18 and chronic HCV patients (n = 18 were quantified by real-time polymerase chain reaction. Results Our results show that IFN-α, TLR3, TLR7 and RIG-I mRNA levels are significantly down-regulated in patients with chronic HCV infection when compared with healthy controls. We also found that the measured levels of TLR3 and TLR7, but not RIG-I, correlated significantly with those of IFN-α Conclusion Monitoring the expression of RNA-sensing receptors like TLR3, TLR7 and RIG-I during the different clinical stages of infection could bring a new source of data about the prognosis of disease.

  15. Respiratory Syncytial Virus Nonstructural Proteins Upregulate SOCS1 and SOCS3 in the Different Manner from Endogenous IFN Signaling

    Directory of Open Access Journals (Sweden)

    Junwen Zheng

    2015-01-01

    Full Text Available Respiratory syncytial virus (RSV infection upregulates genes of the suppressor of cytokine signaling (SOCS family, which utilize a feedback loop to inhibit type I interferon dependent antiviral signaling pathway. Here, we reconstituted RSV nonstructural (NS protein expression plasmids (pNS1, pNS2, and pNS1/2 and tested whether NS1 or NS2 would trigger SOCS1 and SOCS3 protein expression. These NS proteins inhibited interferon- (IFN- α signaling through a mechanism involving the induction of SOCS1 and SOCS3, which appeared to be different from autocrine IFN dependent. NS1 induced both SOCS1 and SOCS3 upregulation, while NS2 only induced SOCS1 expression. The induced expression of SOCS1 and SOCS3 preceded endogenous IFN-signaling activation and inhibited the IFN-inducible antiviral response as well as chemokine induction. Treatments with INF-α and NS proteins both induced SOCS1 expression; however, they had opposing effects on IFN-α-dependent antiviral gene expression. Our results indicate that NS1 and NS2, which induce the expression of SOCS1 or SOCS3, might represent an independent pathway of stimulating endogenous IFN signaling.

  16. The art of rigging

    CERN Document Server

    Biddlecombe, George

    1990-01-01

    The best manual ever produced on rigging a sailing ship, based on extensively revised and updated 1848 edition prepared by Biddlecombe, Master in the Royal Navy. Complete definition of terms, on-shore operations, process of rigging ships, reeving the running rigging and bending sails, rigging brigs, yachts and small vessels, more. 17 plates.

  17. Investigating the Role of TNF-α and IFN-γ Activation on the Dynamics of iNOS Gene Expression in LPS Stimulated Macrophages.

    Directory of Open Access Journals (Sweden)

    Taha Salim

    Full Text Available Macrophage produced inducible nitric oxide synthase (iNOS is known to play a critical role in the proinflammatory response against intracellular pathogens by promoting the generation of bactericidal reactive nitrogen species. Robust and timely production of nitric oxide (NO by iNOS and analogous production of reactive oxygen species are critical components of an effective immune response. In addition to pathogen associated lipopolysaccharides (LPS, iNOS gene expression is dependent on numerous proinflammatory cytokines in the cellular microenvironment of the macrophage, two of which include interferon gamma (IFN-γ and tumor necrosis factor alpha (TNF-α. To understand the synergistic effect of IFN-γ and TNF-α activation, and LPS stimulation on iNOS expression dynamics and NO production, we developed a systems biology based mathematical model. Using our model, we investigated the impact of pre-infection cytokine exposure, or priming, on the system. We explored the essentiality of IFN-γ priming to the robustness of initial proinflammatory response with respect to the ability of macrophages to produce reactive species needed for pathogen clearance. Results from our theoretical studies indicated that IFN-γ and subsequent activation of IRF1 are essential in consequential production of iNOS upon LPS stimulation. We showed that IFN-γ priming at low concentrations greatly increases the effector response of macrophages against intracellular pathogens. Ultimately the model demonstrated that although TNF-α contributed towards a more rapid response time, measured as time to reach maximum iNOS production, IFN-γ stimulation was significantly more significant in terms of the maximum expression of iNOS and the concentration of NO produced.

  18. Investigating the Role of TNF-α and IFN-γ Activation on the Dynamics of iNOS Gene Expression in LPS Stimulated Macrophages.

    Science.gov (United States)

    Salim, Taha; Sershen, Cheryl L; May, Elebeoba E

    2016-01-01

    Macrophage produced inducible nitric oxide synthase (iNOS) is known to play a critical role in the proinflammatory response against intracellular pathogens by promoting the generation of bactericidal reactive nitrogen species. Robust and timely production of nitric oxide (NO) by iNOS and analogous production of reactive oxygen species are critical components of an effective immune response. In addition to pathogen associated lipopolysaccharides (LPS), iNOS gene expression is dependent on numerous proinflammatory cytokines in the cellular microenvironment of the macrophage, two of which include interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α). To understand the synergistic effect of IFN-γ and TNF-α activation, and LPS stimulation on iNOS expression dynamics and NO production, we developed a systems biology based mathematical model. Using our model, we investigated the impact of pre-infection cytokine exposure, or priming, on the system. We explored the essentiality of IFN-γ priming to the robustness of initial proinflammatory response with respect to the ability of macrophages to produce reactive species needed for pathogen clearance. Results from our theoretical studies indicated that IFN-γ and subsequent activation of IRF1 are essential in consequential production of iNOS upon LPS stimulation. We showed that IFN-γ priming at low concentrations greatly increases the effector response of macrophages against intracellular pathogens. Ultimately the model demonstrated that although TNF-α contributed towards a more rapid response time, measured as time to reach maximum iNOS production, IFN-γ stimulation was significantly more significant in terms of the maximum expression of iNOS and the concentration of NO produced.

  19. We Can Still Be Friends: IFN-γ Breaks Up Macrophage Enhancers.

    Science.gov (United States)

    Novakovic, Boris; Wang, Cheng; Logie, Colin

    2017-08-15

    Interferon (IFN)-γ can prime macrophages for inflammatory responses by several mechanisms, including enhancer establishment and gene activation. In this issue of Immunity, Kang et al. (2017) provide insight into the mechanisms of IFN-γ-mediated gene repression as they show that IFN-γ promotes the disassembly of select active enhancers by interfering with enhancer-binding transcription factor MAF. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Type I interferons in tuberculosis: Foe and occasionally friend.

    Science.gov (United States)

    Moreira-Teixeira, Lúcia; Mayer-Barber, Katrin; Sher, Alan; O'Garra, Anne

    2018-05-07

    Tuberculosis remains one of the leading causes of mortality worldwide, and, despite its clinical significance, there are still significant gaps in our understanding of pathogenic and protective mechanisms triggered by Mycobacterium tuberculosis infection. Type I interferons (IFN) regulate a broad family of genes that either stimulate or inhibit immune function, having both host-protective and detrimental effects, and exhibit well-characterized antiviral activity. Transcriptional studies have uncovered a potential deleterious role for type I IFN in active tuberculosis. Since then, additional studies in human tuberculosis and experimental mouse models of M. tuberculosis infection support the concept that type I IFN promotes both bacterial expansion and disease pathogenesis. More recently, studies in a different setting have suggested a putative protective role for type I IFN. In this study, we discuss the mechanistic and contextual factors that determine the detrimental versus beneficial outcomes of type I IFN induction during M. tuberculosis infection, from human disease to experimental mouse models of tuberculosis. © 2018 Moreira-Teixeira et al.

  1. Antiviral Efficacy and Host Innate Immunity Associated with SB 9200 Treatment in the Woodchuck Model of Chronic Hepatitis B.

    Directory of Open Access Journals (Sweden)

    Kyle E Korolowicz

    Full Text Available SB 9200, an oral prodrug of the dinucleotide SB 9000, is being developed for the treatment of chronic hepatitis B virus (HBV infection and represents a novel class of antivirals. SB 9200 is thought to activate the viral sensor proteins, retinoic acid-inducible gene 1 (RIG-I and nucleotide-binding oligomerization domain-containing protein 2 (NOD2 resulting in interferon (IFN mediated antiviral immune responses in virus-infected cells. Additionally, the binding of SB 9200 to these sensor proteins could also sterically block the ability of the viral polymerase to access pre-genomic RNA for nucleic acid synthesis. The immune stimulating and direct antiviral properties of SB 9200 were evaluated in woodchucks chronically infected with woodchuck hepatitis virus (WHV by daily, oral dosing at 15 and 30 mg/kg for 12 weeks. Prolonged treatment resulted in 2.2 and 3.7 log10 reductions in serum WHV DNA and in 0.5 and 1.6 log10 declines in serum WHV surface antigen from pretreatment level with the lower or higher dose of SB 9200, respectively. SB 9200 treatment also resulted in lower hepatic levels of WHV nucleic acids and antigen and reduced liver inflammation. Following treatment cessation, recrudescence of viral replication was observed but with dose-dependent delays in viral relapse. The antiviral effects were associated with dose-dependent and long-lasting induction of IFN-α, IFN-β and IFN-stimulated genes in blood and liver, which correlated with the prolonged activation of the RIG-I/NOD2 pathway and hepatic presence of elevated RIG-I protein levels. These results suggest that in addition to a direct antiviral activity, SB 9200 induces antiviral immunity during chronic hepadnaviral infection via activation of the viral sensor pathway.

  2. The Absent in Melanoma 2-Like Receptor IFN-Inducible Protein 16 as an Inflammasome Regulator in Systemic Lupus Erythematosus: The Dark Side of Sensing Microbes

    Directory of Open Access Journals (Sweden)

    Valeria Caneparo

    2018-05-01

    Full Text Available Absent in melanoma 2 (AIM2-like receptors (ALRs are a newly characterized class of pathogen recognition receptors (PRRs involved in cytosolic and nuclear pathogen DNA recognition. In recent years, two ALR family members, the interferon (IFN-inducible protein 16 (IFI16 and AIM2, have been linked to the pathogenesis of various autoimmune diseases, among which systemic lupus erythematosus (SLE has recently gained increasing attention. SLE patients are indeed often characterized by constitutively high serum IFN levels and increased expression of IFN-stimulated genes due to an abnormal response to pathogens and/or incorrect self-DNA recognition process. Consistently, we and others have shown that IFI16 is overexpressed in a wide range of autoimmune diseases where it triggers production of specific autoantibodies. In addition, evidence from mouse models supports a model whereby ALRs are required for IFN-mediated host response to both exogenous and endogenous DNA. Following interaction with cytoplasmic or nuclear nucleic acids, ALRs can form a functional inflammasome through association with the adaptor ASC [apoptosis-associated speck-like protein containing a caspase recruitment domain (CARD] and with procaspase-1. Importantly, inflammasome-mediated upregulation of IL-1β and IL-18 production positively correlates with SLE disease severity. Therefore, targeting ALR sensors and their downstream pathways represents a promising alternative therapeutic approach for SLE and other systemic autoimmune diseases.

  3. Influenza A virus inhibits type I IFN signaling via NF-kappaB-dependent induction of SOCS-3 expression.

    Directory of Open Access Journals (Sweden)

    Eva-K Pauli

    2008-11-01

    Full Text Available The type I interferon (IFN system is a first line of defense against viral infections. Viruses have developed various mechanisms to counteract this response. So far, the interferon antagonistic activity of influenza A viruses was mainly observed on the level of IFNbeta gene induction via action of the viral non-structural protein 1 (NS1. Here we present data indicating that influenza A viruses not only suppress IFNbeta gene induction but also inhibit type I IFN signaling through a mechanism involving induction of the suppressor of cytokine signaling-3 (SOCS-3 protein. Our study was based on the observation that in cells that were infected with influenza A virus and subsequently stimulated with IFNalpha/beta, phosphorylation of the signal transducer and activator of transcription protein 1 (STAT1 was strongly reduced. This impaired STAT1 activation was not due to the action of viral proteins but rather appeared to be induced by accumulation of viral 5' triphosphate RNA in the cell. SOCS proteins are potent endogenous inhibitors of Janus kinase (JAK/STAT signaling. Closer examination revealed that SOCS-3 but not SOCS-1 mRNA levels increase in an RNA- and nuclear factor kappa B (NF-kappaB-dependent but type I IFN-independent manner early in the viral replication cycle. This direct viral induction of SOCS-3 mRNA and protein expression appears to be relevant for suppression of the antiviral response since in SOCS-3 deficient cells a sustained phosphorylation of STAT1 correlated with elevated expression of type I IFN-dependent genes. As a consequence, progeny virus titers were reduced in SOCS-3 deficient cells or in cells were SOCS-3 expression was knocked-down by siRNA. These data provide the first evidence that influenza A viruses suppress type I IFN signaling on the level of JAK/STAT activation. The inhibitory effect is at least in part due to the induction of SOCS-3 gene expression, which results in an impaired antiviral response.

  4. Central Role of ULK1 in Type I Interferon Signaling

    Directory of Open Access Journals (Sweden)

    Diana Saleiro

    2015-04-01

    Full Text Available We provide evidence that the Unc-51-like kinase 1 (ULK1 is activated during engagement of the type I interferon (IFN receptor (IFNR. Our studies demonstrate that the function of ULK1 is required for gene transcription mediated via IFN-stimulated response elements (ISRE and IFNγ activation site (GAS elements and controls expression of key IFN-stimulated genes (ISGs. We identify ULK1 as an upstream regulator of p38α mitogen-activated protein kinase (MAPK and establish that the regulatory effects of ULK1 on ISG expression are mediated possibly by engagement of the p38 MAPK pathway. Importantly, we demonstrate that ULK1 is essential for antiproliferative responses and type I IFN-induced antineoplastic effects against malignant erythroid precursors from patients with myeloproliferative neoplasms. Together, these data reveal a role for ULK1 as a key mediator of type I IFNR-generated signals that control gene transcription and induction of antineoplastic responses.

  5. Mobile Digital Recording: Adequacy of the iRig and iOS Device for Acoustic and Perceptual Analysis of Normal Voice.

    Science.gov (United States)

    Oliveira, Gisele; Fava, Gaetano; Baglione, Melody; Pimpinella, Michael

    2017-03-01

    To determine whether the iRig and iOS device recording system is comparable with a standard computer recording system for digital voice recording. Thirty-seven vocally healthy adults, between ages 20 and 62, with a mean age of 33.9 years, 13 males and 24 females, were recruited. Recordings were simultaneously digitalized in an iPad and iPhone using a unidirectional condenser microphone for smartphones/tablets (iRig Mic, IK Multimedia) and in a computer laptop (Dell-Inspiron) using a unidirectional condenser microphone (Samson-CL5) connected to a preamplifier with phantom power. Both microphones were lined up at an equal fixed distance from the subject's mouth. Speech tasks consisted of a sustained vowel "ah" at comfortable pitch/loudness, counting from 1 to 10, and a glissando "ah" from a low to a high note. The samples captured on the iOS devices were transferred via SoundCloud in WAV format, and analyzed using the Praat software. The acoustic parameters measured were mean, min, and max F0, SD F0, jitter local, jitter rap, jitter ppq5, jitter ddp, shimmer local, shimmer local-dB, shimmer apq3, shimmer apq5, shimmer apq11, shimmer dda, NHR, and HNR. There were no statistically significant differences for any parameter and speech task analyzed for both iOS devices as compared with the gold standard computer/preamp system (all P values > 0.050). In addition, there were no statistical differences in the perceptual identification of the recordings among devices (P device may provide reliable digital recording of normal voices. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  6. Reversible assembly of protein-DNA nanostructures triggered by mediated electron transfer

    International Nuclear Information System (INIS)

    Vogt, Stephan; Wenderhold-Reeb, Sabine; Nöll, Gilbert

    2017-01-01

    Stable protein-DNA nanostructures have been assembled by reconstitution of the multi-ligand binding flavoprotein dodecin on top of flavin-terminated dsDNA monolayers on gold electrodes. These structures could be disassembled by electrochemical flavin reduction via mediated electron transfer. For this purpose a negative potential was applied at the Au working electrode in the presence of the redox mediator bis-(ammoniumethyl)-4,4′-bipyridinium tetrabromide. The stepwise formation of the flavin-terminated dsDNA monolayers as well as the binding and electrochemically triggered release of apododecin were monitored by surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) measurements. The assembly and disassembly of the protein-DNA nanostructures were fully reversible processes, which could be carried out multiple times at the same flavin-dsDNA modified surface. When a negative potential was applied in the absence of a redox mediator apododecin could not be released, i.e. direct electron transfer was not possible. As alternative redox mediators also methylene blue and phenosafranine were studied, but in the presence of these molecules apododecin was released without applying a potential, probably because the tricyclic aromatic compounds are able to replace the flavins at the binding sites.

  7. Critical role of constitutive type I interferon response in bronchial epithelial cell to influenza infection.

    Directory of Open Access Journals (Sweden)

    Alan C-Y Hsu

    Full Text Available Innate antiviral responses in bronchial epithelial cells (BECs provide the first line of defense against respiratory viral infection and the effectiveness of this response is critically dependent on the type I interferons (IFNs. However the importance of the antiviral responses in BECs during influenza infection is not well understood. We profiled the innate immune response to infection with H3N2 and H5N1 virus using Calu-3 cells and primary BECs to model proximal airway cells. The susceptibility of BECs to influenza infection was not solely dependent on the sialic acid-bearing glycoprotein, and antiviral responses that occurred after viral endocytosis was more important in limiting viral replication. The early antiviral response and apoptosis correlated with the ability to limit viral replication. Both viruses reduced RIG-I associated antiviral responses and subsequent induction of IFN-β. However it was found that there was constitutive release of IFN-β by BECs and this was critical in inducing late antiviral signaling via type I IFN receptors, and was crucial in limiting viral infection. This study characterizes anti-influenza virus responses in airway epithelial cells and shows that constitutive IFN-β release plays a more important role in initiating protective late IFN-stimulated responses during human influenza infection in bronchial epithelial cells.

  8. STING-Dependent Cytosolic DNA Sensing Promotes Radiation-Induced Type I Interferon-Dependent Antitumor Immunity in Immunogenic Tumors.

    Science.gov (United States)

    Deng, Liufu; Liang, Hua; Xu, Meng; Yang, Xuanming; Burnette, Byron; Arina, Ainhoa; Li, Xiao-Dong; Mauceri, Helena; Beckett, Michael; Darga, Thomas; Huang, Xiaona; Gajewski, Thomas F; Chen, Zhijian J; Fu, Yang-Xin; Weichselbaum, Ralph R

    2014-11-20

    Ionizing radiation-mediated tumor regression depends on type I interferon (IFN) and the adaptive immune response, but several pathways control I IFN induction. Here, we demonstrate that adaptor protein STING, but not MyD88, is required for type I IFN-dependent antitumor effects of radiation. In dendritic cells (DCs), STING was required for IFN-? induction in response to irradiated-tumor cells. The cytosolic DNA sensor cyclic GMP-AMP (cGAMP) synthase (cGAS) mediated sensing of irradiated-tumor cells in DCs. Moreover, STING was essential for radiation-induced adaptive immune responses, which relied on type I IFN signaling on DCs. Exogenous IFN-? treatment rescued the cross-priming by cGAS or STING-deficient DCs. Accordingly, activation of STING by a second messenger cGAMP administration enhanced antitumor immunity induced by radiation. Thus radiation-mediated antitumor immunity in immunogenic tumors requires a functional cytosolic DNA-sensing pathway and suggests that cGAMP treatment might provide a new strategy to improve radiotherapy. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Disruption of TLR3 signaling due to cleavage of TRIF by the hepatitis A virus protease-polymerase processing intermediate, 3CD.

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    Lin Qu

    2011-09-01

    Full Text Available Toll-like receptor 3 (TLR3 and cytosolic RIG-I-like helicases (RIG-I and MDA5 sense viral RNAs and activate innate immune signaling pathways that induce expression of interferon (IFN through specific adaptor proteins, TIR domain-containing adaptor inducing interferon-β (TRIF, and mitochondrial antiviral signaling protein (MAVS, respectively. Previously, we demonstrated that hepatitis A virus (HAV, a unique hepatotropic human picornavirus, disrupts RIG-I/MDA5 signaling by targeting MAVS for cleavage by 3ABC, a precursor of the sole HAV protease, 3C(pro, that is derived by auto-processing of the P3 (3ABCD segment of the viral polyprotein. Here, we show that HAV also disrupts TLR3 signaling, inhibiting poly(I:C-stimulated dimerization of IFN regulatory factor 3 (IRF-3, IRF-3 translocation to the nucleus, and IFN-β promoter activation, by targeting TRIF for degradation by a distinct 3ABCD processing intermediate, the 3CD protease-polymerase precursor. TRIF is proteolytically cleaved by 3CD, but not by the mature 3C(pro protease or the 3ABC precursor that degrades MAVS. 3CD-mediated degradation of TRIF depends on both the cysteine protease activity of 3C(pro and downstream 3D(pol sequence, but not 3D(pol polymerase activity. Cleavage occurs at two non-canonical 3C(pro recognition sequences in TRIF, and involves a hierarchical process in which primary cleavage at Gln-554 is a prerequisite for scission at Gln-190. The results of mutational studies indicate that 3D(pol sequence modulates the substrate specificity of the upstream 3C(pro protease when fused to it in cis in 3CD, allowing 3CD to target cleavage sites not normally recognized by 3C(pro. HAV thus disrupts both RIG-I/MDA5 and TLR3 signaling pathways through cleavage of essential adaptor proteins by two distinct protease precursors derived from the common 3ABCD polyprotein processing intermediate.

  10. To achieve an earlier IFN-γ response is not sufficient to control Mycobacterium tuberculosis infection in mice.

    Science.gov (United States)

    Vilaplana, Cristina; Prats, Clara; Marzo, Elena; Barril, Carles; Vegué, Marina; Diaz, Jorge; Valls, Joaquim; López, Daniel; Cardona, Pere-Joan

    2014-01-01

    The temporo-spatial relationship between the three organs (lung, spleen and lymph node) involved during the initial stages of Mycobacterium tuberculosis infection has been poorly studied. As such, we performed an experimental study to evaluate the bacillary load in each organ after aerosol or intravenous infection and developed a mathematical approach using the data obtained in order to extract conclusions. The results showed that higher bacillary doses result in an earlier IFN-γ response, that a certain bacillary load (BL) needs to be reached to trigger the IFN-γ response, and that control of the BL is not immediate after onset of the IFN-γ response, which might be a consequence of the spatial dimension. This study may have an important impact when it comes to designing new vaccine candidates as it suggests that triggering an earlier IFN-γ response might not guarantee good infection control, and therefore that additional properties should be considered for these candidates.

  11. IFN-γ extends the immune functions of Guanylate Binding Proteins to inflammasome-independent antibacterial activities during Francisella novicida infection.

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    Pierre Wallet

    2017-10-01

    Full Text Available Guanylate binding proteins (GBPs are interferon-inducible proteins involved in the cell-intrinsic immunity against numerous intracellular pathogens. The molecular mechanisms underlying the potent antibacterial activity of GBPs are still unclear. GBPs have been functionally linked to the NLRP3, the AIM2 and the caspase-11 inflammasomes. Two opposing models are currently proposed to explain the GBPs-inflammasome link: i GBPs would target intracellular bacteria or bacteria-containing vacuoles to increase cytosolic PAMPs release ii GBPs would directly facilitate inflammasome complex assembly. Using Francisella novicida infection, we investigated the functional interactions between GBPs and the inflammasome. GBPs, induced in a type I IFN-dependent manner, are required for the F. novicida-mediated AIM2-inflammasome pathway. Here, we demonstrate that GBPs action is not restricted to the AIM2 inflammasome, but controls in a hierarchical manner the activation of different inflammasomes complexes and apoptotic caspases. IFN-γ induces a quantitative switch in GBPs levels and redirects pyroptotic and apoptotic pathways under the control of GBPs. Furthermore, upon IFN-γ priming, F. novicida-infected macrophages restrict cytosolic bacterial replication in a GBP-dependent and inflammasome-independent manner. Finally, in a mouse model of tularemia, we demonstrate that the inflammasome and the GBPs are two key immune pathways functioning largely independently to control F. novicida infection. Altogether, our results indicate that GBPs are the master effectors of IFN-γ-mediated responses against F. novicida to control antibacterial immune responses in inflammasome-dependent and independent manners.

  12. Ribavirin enhances IFN-α signalling and MxA expression: a novel immune modulation mechanism during treatment of HCV.

    Directory of Open Access Journals (Sweden)

    Nigel J Stevenson

    Full Text Available The nucleoside analogue Ribavirin significantly increases patient response to IFN-α treatment of HCV, by directly inhibiting viral replication. Recent studies indicate that Ribavirin also regulates immunity and we propose that Ribavirin enhances specific interferon sensitive gene (ISG expression by amplifying the IFN-α-JAK/STAT pathway. We found that IFN-α-induced STAT1 and STAT3 phosphorylation was increased in hepatocytes co-treated with Ribavirin and IFN-α, compared to IFN-α alone. Ribavirin specifically enhanced IFN-α induced mRNA and protein of the anti-viral mediator MxA, which co-localised with HCV core protein. These novel findings indicate for the first time that Ribavirin, in addition to its viral incorporation, also enhances IFN-α-JAK/STAT signalling, leading to a novel MxA-mediated immuno-modulatory mechanism that may enhance IFN-α anti-viral activity against HCV.

  13. SH2 modified STAT1 induces HLA-I expression and improves IFN-γ signaling in IFN-α resistant HCV replicon cells.

    Directory of Open Access Journals (Sweden)

    Bret Poat

    2010-09-01

    Full Text Available We have developed multiple stable cell lines containing subgenomic HCV RNA that are resistant to treatment with interferon alpha (IFN-α. Characterization of these IFN-α resistant replicon cells showed defects in the phosphorylation and nuclear translocation of STAT1 and STAT2 proteins due to a defective Jak-STAT pathway.In this study, we have developed an alternative strategy to overcome interferon resistance in a cell culture model by improving intracellular STAT1 signaling. An engineered STAT1-CC molecule with double cysteine substitutions in the Src-homology 2 (SH2 domains of STAT1 (at Ala-656 and Asn-658 efficiently phosphorylates and translocates to the nucleus of IFN-resistant cells in an IFN-γ dependent manner. Transfection of a plasmid clone containing STAT1-CC significantly activated the GAS promoter compared to wild type STAT1 and STAT3. The activity of the engineered STAT1-CC is dependent upon the phosphorylation of tyrosine residue 701, since the construct with a substituted phenylalanine residue at position 701 (STAT1-CC-Y701F failed to activate GAS promoter in the replicon cells. Intracellular expression of STAT1-CC protein showed phosphorylation and nuclear translocation in the resistant cell line after IFN-γ treatment. Transient transfection of STAT1-CC plasmid clone into an interferon resistant cell line resulted in inhibition of viral replication and viral clearance in an IFN-γ dependent manner. Furthermore, the resistant replicon cells transfected with STAT1-CC constructs significantly up regulated surface HLA-1 expression when compared to the wild type and Y to F mutant controls.These results suggest that modification of the SH2 domain of the STAT1 molecule allows for improved IFN-γ signaling through increased STAT1 phosphorylation, nuclear translocation, HLA-1 surface expression, and prolonged interferon antiviral gene activation.

  14. TREX1 deficiency triggers cell-autonomous immunity in a cGAS-dependent manner.

    Science.gov (United States)

    Ablasser, Andrea; Hemmerling, Inga; Schmid-Burgk, Jonathan L; Behrendt, Rayk; Roers, Axel; Hornung, Veit

    2014-06-15

    Cytosolic detection of DNA is crucial for the initiation of antiviral immunity but can also cause autoimmunity in the context of endogenous nucleic acids being sensed. Mutations in the human 3' repair exonuclease 1 (TREX1) have been linked to the type I IFN-associated autoimmune disease Aicardi-Goutières syndrome. The exact mechanisms driving unabated type I IFN responses in the absence of TREX1 are only partly understood, but it appears likely that accumulation of endogenous DNA species triggers a cell-autonomous immune response by activating a cytosolic DNA receptor. In this article, we demonstrate that knocking out the DNA sensor cyclic GMP-AMP synthase completely abrogates spontaneous induction of IFN-stimulated genes in TREX1-deficient cells. These findings indicate a key role of cyclic GMP-AMP synthase for the initiation of self-DNA-induced autoimmune disorders, thus providing important implications for novel therapeutic approaches. Copyright © 2014 by The American Association of Immunologists, Inc.

  15. Ebi3 Prevents Trypanosoma cruzi-Induced Myocarditis by Dampening IFN-γ-Driven Inflammation

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    Tiago Silva Medina

    2017-09-01

    Full Text Available The identification of anti-inflammatory mediators can reveal important targetable molecules capable of counterbalancing Trypanosoma cruzi-induced myocarditis. Composed of Ebi3 and IL-27p28 subunits, IL-27 is produced by myeloid cells and is able to suppress inflammation by inducing IL-10-producing Tr1 cells, thus emerging as a potential candidate to ameliorate cardiac inflammation induced by T. cruzi. Although IL-27 has been extensively characterized as a suppressive cytokine that prevents liver immunopathogenesis after T. cruzi infection, the mechanisms underlying its effects on T. cruzi-induced myocarditis remain largely unknown. Here, wild-type (WT and Ebi3-deficient animals were intraperitoneally infected with trypomastigotes of T. cruzi Y strain and used to evaluate the potential anti-inflammatory properties of Ebi3 during T. cruzi infection. The survival rates of mice were daily recorded, the frequency of inflammatory cells was analyzed by flow cytometry and inflammatory mediators were measured by ELISA, real-time PCR and PCR array. We reported that T. cruzi-induced myocarditis was prevented by Ebi3. Stressors mainly recognized by TLR2 and TLR4 receptors on myeloid cells were essential to trigger IL-27p28 production. In addition, Ebi3 regulated IFN-γ-mediated myocarditis by promoting an anti-inflammatory environment through IL-10, which was most likely produced by Tr1 cells rather than classical regulatory T cells (Tregs, in the heart tissue of T. cruzi-infected animals. Furthermore, in vivo IFN-γ blockade ameliorated the host survival without compromising the parasite control in the bloodstream. In humans, IL-27p28 was correlated with cardiac protection during Chagas disease. Patients with mild clinical forms of the disease produced high levels of IL-27p28, whereas lower levels were found in those with severe forms. In addition, polymorphic sites at Ebi3 gene were associated with severe cardiomyopathy in patients with Chagas disease

  16. Ebi3 Prevents Trypanosoma cruzi-Induced Myocarditis by Dampening IFN-γ-Driven Inflammation

    Science.gov (United States)

    Medina, Tiago Silva; Oliveira, Gabriela Gonçalves; Silva, Maria Cláudia; David, Bruna Araújo; Silva, Grace Kelly; Fonseca, Denise Morais; Sesti-Costa, Renata; Frade, Amanda Farage; Baron, Monique Andrade; Ianni, Barbara; Pereira, Alexandre Costa; Chevillard, Christophe; Cunha-Neto, Edécio; Marin-Neto, José Antonio; Silva, João Santana

    2017-01-01

    The identification of anti-inflammatory mediators can reveal important targetable molecules capable of counterbalancing Trypanosoma cruzi-induced myocarditis. Composed of Ebi3 and IL-27p28 subunits, IL-27 is produced by myeloid cells and is able to suppress inflammation by inducing IL-10-producing Tr1 cells, thus emerging as a potential candidate to ameliorate cardiac inflammation induced by T. cruzi. Although IL-27 has been extensively characterized as a suppressive cytokine that prevents liver immunopathogenesis after T. cruzi infection, the mechanisms underlying its effects on T. cruzi-induced myocarditis remain largely unknown. Here, wild-type (WT) and Ebi3-deficient animals were intraperitoneally infected with trypomastigotes of T. cruzi Y strain and used to evaluate the potential anti-inflammatory properties of Ebi3 during T. cruzi infection. The survival rates of mice were daily recorded, the frequency of inflammatory cells was analyzed by flow cytometry and inflammatory mediators were measured by ELISA, real-time PCR and PCR array. We reported that T. cruzi-induced myocarditis was prevented by Ebi3. Stressors mainly recognized by TLR2 and TLR4 receptors on myeloid cells were essential to trigger IL-27p28 production. In addition, Ebi3 regulated IFN-γ-mediated myocarditis by promoting an anti-inflammatory environment through IL-10, which was most likely produced by Tr1 cells rather than classical regulatory T cells (Tregs), in the heart tissue of T. cruzi-infected animals. Furthermore, in vivo IFN-γ blockade ameliorated the host survival without compromising the parasite control in the bloodstream. In humans, IL-27p28 was correlated with cardiac protection during Chagas disease. Patients with mild clinical forms of the disease produced high levels of IL-27p28, whereas lower levels were found in those with severe forms. In addition, polymorphic sites at Ebi3 gene were associated with severe cardiomyopathy in patients with Chagas disease. Collectively, we

  17. Contact inhibition and interferon (IFN)-modulated gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Kulesh, D.A.

    1986-01-01

    The relationship between cell morphology, proliferation and contact inhibition was studied in normal and malignant human cells which varied in their sensitivity to contact inhibition. Their ability to proliferate was examined under conditions where the cells were constrained into different shapes. Cell proliferation was quantitated by labeling indices, which were inferred by autoradiography, and by total cell counts. The normal cells (JHU-1, IMR-90) were dependent on cell shape for proliferation capability while the transformed cells (RT4, HT1080) were shape-dependent for proliferation. Interferon (IFN) induced shape-dependent proliferation and contact inhibition in the transformed cells when used at subantiproliferative concentrations. This ability of B-IFN to confer a level of proliferation control which is characteristic of normal fibroblasts suggests a possible relationship between gene expression mediated by IFN and those genes involved in the maintenance of regulated cell proliferation. To evaluate this possibility, cDNA libraries were constructed from IFN-treated and untreated HT1080 cells. The resulting 10 IFN-induced and 11 IFN-repressed sequences were then differentially rescreened using /sup 32/P-cDNA probes. This screening resulted in the identification of at least four cDNA sequences which appeared to be proliferation regulated as well as IFN-modulated. These cloned, regulated cDNA sequences were then used as /sup 32/P-labeled probes to study both the gene expression at the mRNA level employing Northern blotting and slot blotting techniques.

  18. AHP 47: A RIG RGAD PO VISITS LHA SA

    Directory of Open Access Journals (Sweden)

    Pad ma skyid པདྨ་སྐྱིད།

    2017-04-01

    Full Text Available My name is Pad ma skyid. I was born in 1981 in Pan yag Community, 'Bo spa Township, Pad ma County, Mgo log Tibetan Autonomous Prefecture, Mtsho sngon (Qinghai Province. I have eight siblings. Growing up in a black yak-hair tent, we spent our days playing with lambs, foals, and calves. We told all sorts of stories when everyone was in bed - stories about King Ge sar, ghosts, marriages, and tricksters. It was a time for my whole family to relax and share. I heard many A rig rgad po stories from my parents, siblings, and guests. A rig rgad po became part of my childhood. These stories bring back many beautiful memories. ...

  19. Type I Interferon in the Pathogenesis of Lupus

    Science.gov (United States)

    Crow, Mary K.

    2014-01-01

    Investigations of patients with systemic lupus erythematosus (SLE) have applied insights from studies of the innate immune response to define type I interferon (IFN-I), with IFN-α the dominant mediator, as central to the pathogenesis of this prototype systemic autoimmune disease. Genetic association data identify regulators of nucleic acid degradation and components of TLR-independent, endosomal TLR-dependent, and IFN-I signaling pathways as contributors to lupus disease susceptibility. Together with a gene expression signature characterized by IFNI-induced gene transcripts in lupus blood and tissue, those data support the conclusion that many of the immunologic and pathologic features of this disease are a consequence of a persistent self-directed immune reaction driven by IFN-I and mimicking a sustained anti-virus response. This expanding knowledge of the role of IFN-I and the innate immune response suggests candidate therapeutic targets that are being tested in lupus patients. PMID:24907379

  20. cGAS-Mediated Innate Immunity Spreads Intercellularly through HIV-1 Env-Induced Membrane Fusion Sites.

    Science.gov (United States)

    Xu, Shuting; Ducroux, Aurélie; Ponnurangam, Aparna; Vieyres, Gabrielle; Franz, Sergej; Müsken, Mathias; Zillinger, Thomas; Malassa, Angelina; Ewald, Ellen; Hornung, Veit; Barchet, Winfried; Häussler, Susanne; Pietschmann, Thomas; Goffinet, Christine

    2016-10-12

    Upon sensing cytoplasmic retroviral DNA in infected cells, cyclic GMP-AMP (cGAMP) synthase (cGAS) produces the cyclic dinucleotide cGAMP, which activates STING to trigger a type I interferon (IFN) response. We find that membrane fusion-inducing contact between donor cells expressing the HIV envelope (Env) and primary macrophages endogenously expressing the HIV receptor CD4 and coreceptor enable intercellular transfer of cGAMP. This cGAMP exchange results in STING-dependent antiviral IFN responses in target macrophages and protection from HIV infection. Furthermore, under conditions allowing cell-to-cell transmission of HIV-1, infected primary T cells, but not cell-free virions, deliver cGAMP to autologous macrophages through HIV-1 Env and CD4/coreceptor-mediated membrane fusion sites and induce a STING-dependent, but cGAS-independent, IFN response in target cells. Collectively, these findings identify an infection-specific mode of horizontal transfer of cGAMP between primary immune cells that may boost antiviral responses, particularly in infected tissues in which cell-to-cell transmission of virions exceeds cell-free infection. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. PDL1 Signals through Conserved Sequence Motifs to Overcome Interferon-Mediated Cytotoxicity

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    Maria Gato-Cañas

    2017-08-01

    Full Text Available PDL1 blockade produces remarkable clinical responses, thought to occur by T cell reactivation through prevention of PDL1-PD1 T cell inhibitory interactions. Here, we find that PDL1 cell-intrinsic signaling protects cancer cells from interferon (IFN cytotoxicity and accelerates tumor progression. PDL1 inhibited IFN signal transduction through a conserved class of sequence motifs that mediate crosstalk with IFN signaling. Abrogation of PDL1 expression or antibody-mediated PDL1 blockade strongly sensitized cancer cells to IFN cytotoxicity through a STAT3/caspase-7-dependent pathway. Moreover, somatic mutations found in human carcinomas within these PDL1 sequence motifs disrupted motif regulation, resulting in PDL1 molecules with enhanced protective activities from type I and type II IFN cytotoxicity. Overall, our results reveal a mode of action of PDL1 in cancer cells as a first line of defense against IFN cytotoxicity.

  2. Impaired IFN-α-mediated signal in dendritic cells differentiates active from latent tuberculosis.

    Directory of Open Access Journals (Sweden)

    Stefania Parlato

    Full Text Available Individuals exposed to Mycobacterium tuberculosis (Mtb may be infected and remain for the entire life in this condition defined as latent tuberculosis infection (LTBI or develop active tuberculosis (TB. Among the multiple factors governing the outcome of the infection, dendritic cells (DCs play a major role in dictating antibacterial immunity. However, current knowledge on the role of the diverse components of human DCs in shaping specific T-cell response during Mtb infection is limited. In this study, we performed a comparative evaluation of peripheral blood circulating DC subsets as well as of monocyte-derived Interferon-α DCs (IFN-DCs from patients with active TB, subjects with LTBI and healthy donors (HD. The proportion of circulating myeloid BDCA3+ DCs (mDC2 and plasmacytoid CD123+ DCs (pDCs declined significantly in active TB patients compared to HD, whereas the same subsets displayed a remarkable activation in LTBI subjects. Simultaneously, the differentiation of IFN-DCs from active TB patients resulted profoundly impaired compared to those from LTBI and HD individuals. Importantly, the altered developmental trait of IFN-DCs from active TB patients was associated with down-modulation of IFN-linked genes, marked changes in molecular signaling conveying antigen (Ag presentation and full inability to induce Ag-specific T cell response. Thus, these data reveal an important role of IFN-α in determining the induction of Mtb-specific immunity.

  3. ORF7-encoded accessory protein 7a of feline infectious peritonitis virus as a counteragent against IFN-α-induced antiviral response.

    Science.gov (United States)

    Dedeurwaerder, Annelike; Olyslaegers, Dominique A J; Desmarets, Lowiese M B; Roukaerts, Inge D M; Theuns, Sebastiaan; Nauwynck, Hans J

    2014-02-01

    The type I IFN-mediated immune response is the first line of antiviral defence. Coronaviruses, like many other viruses, have evolved mechanisms to evade this innate response, ensuring their survival. Several coronavirus accessory genes play a central role in these pathways, but for feline coronaviruses this has never to our knowledge been studied. As it has been demonstrated previously that ORF7 is essential for efficient replication in vitro and virulence in vivo of feline infectious peritonitis virus (FIPV), the role of this ORF in the evasion of the IFN-α antiviral response was investigated. Deletion of ORF7 from FIPV strain 79-1146 (FIPV-Δ7) rendered the virus more susceptible to IFN-α treatment. Given that ORF7 encodes two proteins, 7a and 7b, it was further explored which of these proteins is active in this mechanism. Providing 7a protein in trans rescued the mutant FIPV-Δ7 from IFN sensitivity, which was not achieved by addition of 7b protein. Nevertheless, addition of protein 7a to FIPV-Δ3Δ7, a FIPV mutant deleted in both ORF3 and ORF7, could no longer increase the replication capacity of this mutant in the presence of IFN. These results indicate that FIPV 7a protein is a type I IFN antagonist and protects the virus from the antiviral state induced by IFN, but it needs the presence of ORF3-encoded proteins to exert its antagonistic function.

  4. Unique nonstructural proteins of Pneumonia Virus of Mice (PVM) promote degradation of interferon (IFN) pathway components and IFN-stimulated gene proteins.

    Science.gov (United States)

    Dhar, Jayeeta; Barik, Sailen

    2016-12-01

    Pneumonia Virus of Mice (PVM) is the only virus that shares the Pneumovirus genus of the Paramyxoviridae family with Respiratory Syncytial Virus (RSV). A deadly mouse pathogen, PVM has the potential to serve as a robust animal model of RSV infection, since human RSV does not fully replicate the human pathology in mice. Like RSV, PVM also encodes two nonstructural proteins that have been implicated to suppress the IFN pathway, but surprisingly, they exhibit no sequence similarity with their RSV equivalents. The molecular mechanism of PVM NS function, therefore, remains unknown. Here, we show that recombinant PVM NS proteins degrade the mouse counterparts of the IFN pathway components. Proteasomal degradation appears to be mediated by ubiquitination promoted by PVM NS proteins. Interestingly, NS proteins of PVM lowered the levels of several ISG (IFN-stimulated gene) proteins as well. These results provide a molecular foundation for the mechanisms by which PVM efficiently subverts the IFN response of the murine cell. They also reveal that in spite of their high sequence dissimilarity, the two pneumoviral NS proteins are functionally and mechanistically similar.

  5. Melanoma NOS1 expression promotes dysfunctional IFN signaling.

    Science.gov (United States)

    Liu, Qiuzhen; Tomei, Sara; Ascierto, Maria Libera; De Giorgi, Valeria; Bedognetti, Davide; Dai, Cuilian; Uccellini, Lorenzo; Spivey, Tara; Pos, Zoltan; Thomas, Jaime; Reinboth, Jennifer; Murtas, Daniela; Zhang, Qianbing; Chouchane, Lotfi; Weiss, Geoffrey R; Slingluff, Craig L; Lee, Peter P; Rosenberg, Steven A; Alter, Harvey; Yao, Kaitai; Wang, Ena; Marincola, Francesco M

    2014-05-01

    In multiple forms of cancer, constitutive activation of type I IFN signaling is a critical consequence of immune surveillance against cancer; however, PBMCs isolated from cancer patients exhibit depressed STAT1 phosphorylation in response to IFN-α, suggesting IFN signaling dysfunction. Here, we demonstrated in a coculture system that melanoma cells differentially impairs the IFN-α response in PBMCs and that the inhibitory potential of a particular melanoma cell correlates with NOS1 expression. Comparison of gene transcription and array comparative genomic hybridization (aCGH) between melanoma cells from different patients indicated that suppression of IFN-α signaling correlates with an amplification of the NOS1 locus within segment 12q22-24. Evaluation of NOS1 levels in melanomas and IFN responsiveness of purified PBMCs from patients indicated a negative correlation between NOS1 expression in melanomas and the responsiveness of PBMCs to IFN-α. Furthermore, in an explorative study, NOS1 expression in melanoma metastases was negatively associated with patient response to adoptive T cell therapy. This study provides a link between cancer cell phenotype and IFN signal dysfunction in circulating immune cells.

  6. Equipment available for automating rig operations

    International Nuclear Information System (INIS)

    McNair, W.L.

    1990-01-01

    Several manufacturers are producing automated rig equipment, from complete systems to individual functions for existing drilling rigs. Significant improvements in well site time, costs of operations, and improved drilling performance have led drilling contractors to install this equipment on their rigs. This paper details some of the equipment available for automating rigs

  7. Characterization of the binding of radioiodinated hybrid recombinant IFN-alpha A/D to murine and human lymphoid cell lines

    International Nuclear Information System (INIS)

    Faltynek, C.R.; Princler, G.L.; Schwabe, M.; Shata, M.T.; Lewis, G.K.; Kamin-Lewis, R.M.

    1990-01-01

    The hybrid recombinant human interferon (IFN) rIFN-alpha A/D was radioiodinated. Specific binding of [125I]rIFN-alpha A/D was observed with both human and murine cell lines. The binding of [125I]rIFN-alpha A/D to human Daudi cells had similar characteristics to the previously described binding of [125I]rIFN-alpha A or -alpha 2. The following lines of evidence demonstrated that [125I]rIFN-alpha A/D bound with high affinity to the same receptor on murine cells as murine IFN-alpha and -beta: (i) the binding of [125I]rIFN-alpha A/D to murine LBRM cells was inhibited to a similar extent by natural murine IFN-alpha, natural murine IFN-beta, and rIFN-A/D; (ii) the Kd (approximately 2 X 10(-10) M) obtained from both competition experiments and saturation binding experiments with [125I]rIFN-alpha A/D was comparable to the previously reported Kd for the binding of natural murine IFN-alpha and -beta to other murine cell lines; (iii) the size of the cross-linked [125I]rIFN-alpha A/D receptor complex formed on murine LBRM cells was similar to the previously reported cross-linked complex formed after binding radioiodinated natural murine IFN-beta to other murine cell lines. Due to the current lack of readily available recombinant murine IFN-alpha or -beta for radiolabeling and the previously demonstrated biological activity of rIFN-alpha A/D on murine cells, [125I]rIFN-alpha A/D should prove to be a useful reagent for further studies of murine IFN receptors

  8. Highly pathogenic avian influenza virus H5N1 controls type I IFN induction in chicken macrophage HD-11 cells: a polygenic trait that involves NS1 and the polymerase complex

    Science.gov (United States)

    2012-01-01

    Background Influenza A viruses are well characterized to antagonize type I IFN induction in infected mammalian cells. However, limited information is available for avian cells. It was hypothesised that avian influenza viruses (AIV) with distinct virulence may interact differently with the avian innate immune system. Therefore, the type I IFN responses induced by highly virulent and low virulent H5N1 AIV and reassortants thereof were analysed in chicken cells. Results The highly pathogenic (HP) AIV A/chicken/Yamaguchi/7/04 (H5N1) (Yama) did not induce type I IFN in infected chicken HD-11 macrophage-like cells. This contrasted with an NS1 mutant Yama virus (Yama-NS1A144V) and with the attenuated H5N1 AIV A/duck/Hokkaido/Vac-1/04 (Vac) carrying the haemagglutinin (HA) of the Yama virus (Vac-Yama/HA), that both induced type I IFN in these cells. The substitution of the NS segment from Yama with that from Vac in the Yama backbone resulted in induction of type I IFN secretion in HD-11 cells. However, vice versa, the Yama NS segment did not prevent type I IFN induction by the Vac-Yama/HA virus. This was different with the PB1/PB2/PA segment reassortant Yama and Vac-Yama/HA viruses. Whereas the Yama virus with the Vac PB1/PB2/PA segments induced type I IFN in HD-11 cells, the Vac-Yama/HA virus with the Yama PB1/PB2/PA segments did not. As reported for mammalian cells, the expression of H5N1 PB2 inhibited the activation of the IFN-β promoter in chicken DF-1 fibroblast cells. Importantly, the Yama PB2 was more potent at inhibiting the IFN-β promoter than the Vac PB2. Conclusions The present study demonstrates that the NS1 protein and the polymerase complex of the HPAIV Yama act in concert to antagonize chicken type I IFN secretion in HD-11 cells. PB2 alone can also exert a partial inhibitory effect on type I IFN induction. In conclusion, the control of type I IFN induction by H5N1 HPAIV represents a complex phenotype that involves a particular viral gene constellation

  9. Anandamide attenuates Th-17 cell-mediated delayed-type hypersensitivity response by triggering IL-10 production and consequent microRNA induction.

    Directory of Open Access Journals (Sweden)

    Austin R Jackson

    Full Text Available Endogenous cannabinoids [endocannabinoids] are lipid signaling molecules that have been shown to modulate immune functions. However, their role in the regulation of Th17 cells has not been studied previously. In the current study, we used methylated Bovine Serum Albumin [mBSA]-induced delayed type hypersensitivity [DTH] response in C57BL/6 mice, mediated by Th17 cells, as a model to test the anti-inflammatory effects of endocannabinoids. Administration of anandamide [AEA], a member of the endocannabinoid family, into mice resulted in significant mitigation of mBSA-induced inflammation, including foot pad swelling, cell infiltration, and cell proliferation in the draining lymph nodes [LN]. AEA treatment significantly reduced IL-17 and IFN-γ production, as well as decreased RORγt expression while causing significant induction of IL-10 in the draining LNs. IL-10 was critical for the AEA-induced mitigation of DTH response inasmuch as neutralization of IL-10 reversed the effects of AEA. We next analyzed miRNA from the LN cells and found that 100 out of 609 miRNA species were differentially regulated in AEA-treated mice when compared to controls. Several of these miRNAs targeted proinflammatory mediators. Interestingly, many of these miRNA were also upregulated upon in vitro treatment of LN cells with IL-10. Together, the current study demonstrates that AEA may suppress Th-17 cell-mediated DTH response by inducing IL-10 which in turn triggers miRNA that target proinflammatory pathways.

  10. Regulation of IFN regulatory factor 4 expression in human T cell leukemia virus-I-transformed T cells.

    Science.gov (United States)

    Sharma, Sonia; Grandvaux, Nathalie; Mamane, Yael; Genin, Pierre; Azimi, Nazli; Waldmann, Thomas; Hiscott, John

    2002-09-15

    IFN regulatory factor (IRF)-4 is a lymphoid/myeloid-restricted member of the IRF transcription factor family that plays an essential role in the homeostasis and function of mature lymphocytes. IRF-4 expression is tightly regulated in resting primary T cells and is transiently induced at the mRNA and protein levels after activation by Ag-mimetic stimuli such as TCR cross-linking or treatment with phorbol ester and calcium ionophore (PMA/ionomycin). However, IRF-4 is constitutively upregulated in human T cell leukemia virus type I (HTLV-I) infected T cells as a direct gene target for the HTLV-I Tax oncoprotein. In this study we demonstrate that chronic IRF-4 expression in HTLV-I-infected T lymphocytes is associated with a leukemic phenotype, and we examine the mechanisms by which continuous production of IRF-4 is achieved in HTLV-I-transformed T cells. IRF-4 expression in HTLV-1-infected cells is driven through activation of the NF-kappaB and NF-AT pathways, resulting in the binding of p50, p65, and c-Rel to the kappaB1 element and p50, c-Rel, and NF-ATp to the CD28RE element within the -617 to -209 region of the IRF-4 promoter. Furthermore, mutation of either the kappaB1 or CD28RE sites blocks Tax-mediated transactivation of the human IRF-4 promoter in T cells. These experiments constitute the first detailed analysis of human IRF-4 transcriptional regulation within the context of HTLV-I infection and transformation of CD4(+) T lymphocytes.

  11. Type I interferons instigate fetal demise after Zika virus infection.

    Science.gov (United States)

    Yockey, Laura J; Jurado, Kellie A; Arora, Nitin; Millet, Alon; Rakib, Tasfia; Milano, Kristin M; Hastings, Andrew K; Fikrig, Erol; Kong, Yong; Horvath, Tamas L; Weatherbee, Scott; Kliman, Harvey J; Coyne, Carolyn B; Iwasaki, Akiko

    2018-01-05

    Zika virus (ZIKV) infection during pregnancy is associated with adverse fetal outcomes, including microcephaly, growth restriction, and fetal demise. Type I interferons (IFNs) are essential for host resistance against ZIKV, and IFN-α/β receptor (IFNAR)-deficient mice are highly susceptible to ZIKV infection. Severe fetal growth restriction with placental damage and fetal resorption is observed after ZIKV infection of type I IFN receptor knockout ( Ifnar1 -/- ) dams mated with wild-type sires, resulting in fetuses with functional type I IFN signaling. The role of type I IFNs in limiting or mediating ZIKV disease within this congenital infection model remains unknown. In this study, we challenged Ifnar1 -/- dams mated with Ifnar1 +/- sires with ZIKV. This breeding scheme enabled us to examine pregnant dams that carry a mixture of fetuses that express ( Ifnar1 +/- ) or do not express IFNAR ( Ifnar1 -/- ) within the same uterus. Virus replicated to a higher titer in the placenta of Ifnar1 -/- than within the Ifnar1 +/- concepti. Yet, rather unexpectedly, we found that only Ifnar1 +/- fetuses were resorbed after ZIKV infection during early pregnancy, whereas their Ifnar1 -/- littermates continue to develop. Analyses of the fetus and placenta revealed that, after ZIKV infection, IFNAR signaling in the conceptus inhibits development of the placental labyrinth, resulting in abnormal architecture of the maternal-fetal barrier. Exposure of midgestation human chorionic villous explants to type I IFN, but not type III IFNs, altered placental morphology and induced cytoskeletal rearrangements within the villous core. Our results implicate type I IFNs as a possible mediator of pregnancy complications, including spontaneous abortions and growth restriction, in the context of congenital viral infections. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  12. Silencing of IFN-stimulated gene transcription is regulated by histone H1 and its chaperone TAF-I.

    Science.gov (United States)

    Kadota, Shinichi; Nagata, Kyosuke

    2014-07-01

    Chromatin structure and its alteration play critical roles in the regulation of transcription. However, the transcriptional silencing mechanism with regard to the chromatin structure at an unstimulated state of the interferon (IFN)-stimulated gene (ISG) remains unclear. Here we investigated the role of template activating factor-I (TAF-I, also known as SET) in ISG transcription. Knockdown (KD) of TAF-I increased ISG transcript and simultaneously reduced the histone H1 level on the ISG promoters during the early stages of transcription after IFN stimulation from the unstimulated state. The transcription factor levels on the ISG promoters were increased in TAF-I KD cells only during the early stages of transcription. Furthermore, histone H1 KD also increased ISG transcript. TAF-I and histone H1 double KD did not show the additive effect in ISG transcription, suggesting that TAF-I and histone H1 may act on the same regulatory pathway to control ISG transcription. In addition, TAF-I KD and histone H1 KD affected the chromatin structure near the ISG promoters. On the basis of these findings, we propose that TAF-I and its target histone H1 are key regulators of the chromatin structure at the ISG promoter to maintain the silent state of ISG transcription. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  13. {open_quote}Nintendo Rig{close_quote} lets two men do work of three on traditional servicing rig

    Energy Technology Data Exchange (ETDEWEB)

    Rintoul, B.

    1996-01-01

    New well servicing rig saves costs and increases safety by using a robot derrickman. The rigs is called the Nintendo Rig, taking the name from the joystick that controls the robot on the racking board 25 feet above the ground. An automated tong/slip package permanently mounted on the front of the rig handles pipe and rods on the ground.

  14. Oxidative Stress Facilitates IFN-γ-Induced Mimic Extracellular Trap Cell Death in A549 Lung Epithelial Cancer Cells.

    Science.gov (United States)

    Lin, Chiou-Feng; Chen, Chia-Ling; Chien, Shun-Yi; Tseng, Po-Chun; Wang, Yu-Chih; Tsai, Tsung-Ting

    2016-01-01

    We previously demonstrated that IFN-γ induces an autophagy-regulated mimic extracellular trap cell death (ETosis) in A549 human lung cancer cells. Regarding reactive oxygen species (ROS) are involved in ETosis, this study investigated the role of oxidative stress. After IFN-γ stimulation, a necrosis-like cell death mimic ETosis occurred accompanied by the inhibition of cell growth, aberrant nuclear staining, and nucleosome release. ROS were generated in a time-dependent manner with an increase in NADPH oxidase component protein expression. STAT1-mediated IFN regulatory factor-1 activation was essential for upregulating ROS production. By genetically silencing p47phox, IFN-γ-induced ROS and mimic ETosis were significantly attenuated. This mechanistic study indicated that ROS may mediate DNA damage followed by histone H3 citrullination. Furthermore, ROS promoted IFN-γ-induced mimic ETosis in cooperation with autophagy. These findings further demonstrate that ROS regulates IFN-γ-induced mimic ETosis in lung epithelial malignancy.

  15. The mobile rig industry

    International Nuclear Information System (INIS)

    Karlsen, J.K.

    1992-08-01

    This study is part of the project ''A competitive Norway'', based on the theories and methods presented in the book ''The competitive advantage of nations'', by Michael E. Porter. The rig market may be segmented according to the type of service, the geographical market and the type of equipment. The focus of the report is exploration and appraisal drilling using jackup rigs and semi-submersible rigs in the Northwestern European market. Market shares of Norwegian, other European and US suppliers in the jackup and semi-submerisible market segments on the Norwegian continental shelf and the entire Northwestern market are presented. The main driving force behind the rig demand is the price of oil, but technological trends and changes in relative importance of the various geographical markets are also important. The industry is fairly fragmented on the supplier side, while the oil companies as customers have substantial bargaining power. There are high exit barriers because of the high capital intensity of the business. Combined with a highly volatile demand, this forces the industry through cycles of low capacity utilization and depressed rig day rates. 8 refs., 19 figs., 2 tabs

  16. ISG15 Inhibits IFN-α-Resistant Liver Cancer Cell Growth

    Directory of Open Access Journals (Sweden)

    Xin-xing Wan

    2013-01-01

    Full Text Available Hepatocellular carcinoma (HCC is one of the most prevalent tumors worldwide. Interferon-α (IFN-α has been widely used in the treatment of HCC, but patients eventually develop resistance. ISG15 ubiquitin-like modifier (ISG15 is a ubiquitin-like protein transcriptionally regulated by IFN-α which shows antivirus and antitumor activities. However, the exact role of ISG15 is unknown. In the present study, we showed that IFN-α significantly induced ISG15 expression but failed to induce HepG2 cell apoptosis, whereas transient overexpression of ISG15 dramatically increased HepG2 cell apoptosis. ISG15 overexpression increased overall protein ubiquitination, which was not observed in cells with IFN-α-induced ISG15 expression, suggesting that IFN-α treatment not only induced the expression of ISG15 but also inhibited ISG15-mediated ubiquitination. The tumor suppressor p53 and p21 proteins are the key regulators of cell survival and death in response to stress signals such as DNA damage. We showed that p53 or p21 is only up regulated in HepG2 cells ectopically expressing ISG15, but not in the presence of IFN-α-induced ISG15. Our results suggest that ISG15 overexpression could be developed into a powerful gene-therapeutic tool for treating IFN-α-resistant HCC.

  17. Trastuzumab triggers phagocytic killing of high HER2 cancer cells in vitro and in vivo by interaction with Fcγ receptors on macrophages.

    Science.gov (United States)

    Shi, Yun; Fan, Xuejun; Deng, Hui; Brezski, Randall J; Rycyzyn, Michael; Jordan, Robert E; Strohl, William R; Zou, Quanming; Zhang, Ningyan; An, Zhiqiang

    2015-05-01

    Trastuzumab has been used for the treatment of HER2-overexpressing breast cancer for more than a decade, but the mechanisms of action for the therapy are still being actively investigated. Ab-dependent cell-mediated cytotoxicity mediated by NK cells is well recognized as one of the key mechanisms of action for trastuzumab, but trastuzumab-mediated Ab-dependent cellular phagocytosis (ADCP) has not been established. In this study, we demonstrate that macrophages, by way of phagocytic engulfment, can mediate ADCP and cancer cell killing in the presence of trastuzumab. Increased infiltration of macrophages in the tumor tissue was associated with enhanced efficacy of trastuzumab whereas depletion of macrophages resulted in reduced antitumor efficacy in mouse xenograft tumor models. Among the four mouse FcγRs, FcγRIV exhibits the strongest binding affinity to trastuzumab. Knockdown of FcγRIV in mouse macrophages reduced cancer cell killing and ADCP activity triggered by trastuzumab. Consistently, an upregulation of FcγRIV expression by IFNtriggered an increased ADCP activity by trastuzumab. In an analogous fashion, IFN-γ priming of human macrophages increased the expression of FcγRIII, the ortholog of murine FcγRIV, and increased trastuzumab-mediated cancer cell killing. Thus, in two independent systems, the results indicated that activation of macrophages in combination with trastuzumab can serve as a therapeutic strategy for treating high HER2 breast cancer by boosting ADCP killing of cancer cells. Copyright © 2015 by The American Association of Immunologists, Inc.

  18. 40th annual Reed rig census

    International Nuclear Information System (INIS)

    Fitts, R.L.; Stokes, T.A.

    1992-01-01

    This paper reports that declines characterize the 1992 rig census-in the number of available drilling rigs, in the number of active rigs, in rig utilization rate, in the number of rig owners and in industry optimism. The number of rotary rigs available for U.S. drilling fell by 255 units (11.3%) during the past 12 months, an attrition rate almost four times greater than in 1991. But despite the high attrition, only 59.7% of remaining rigs were working during the time the census was taken. Results of the 1992 census bring emphasis to an industry trend that became apparent in early 1991. The major oil companies, and many independents, continued their exodus form the U.S., and the remaining independents, which were hurt by low natural gas prices and unfavorable tax treatment of intangible drilling costs, were not able to pick u the drilling slack. Consequently, the past year has been disastrous for many U.S. drilling contractors, and the outlook for this industry segment remains bleak

  19. Rig`s electricity to power top drive drilling system

    Energy Technology Data Exchange (ETDEWEB)

    Liderth, D.

    1996-05-01

    Permanent magnet brushless electric motors to supply torque to more space-efficient top drive drilling assemblies was the solution designed by Kaman Electromagnetic Corporation, working hand-in-hand with Calgary-based Tesco Drilling Technology, to remedy problems created by the bulkiness of standard hydraulic top drive systems. The biggest advantage of using electric over hydraulic top drive systems is the ability to tap into the rig`s existing power source, which lowers both cost and effort. A better power to weight ratio and reduced maintenance requirements are other desirable advantages.

  20. Dose dependent activation of retinoic acid-inducible gene-I promotes both proliferation and apoptosis signals in human head and neck squamous cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Jingzhou Hu

    Full Text Available The retinoic-acid-inducible gene (RIG-like receptor (RLR family proteins are major pathogen reorganization receptors (PRR responsible for detection of viral RNA, which initiates antiviral response. Here, we evaluated the functional role of one RLR family member, RIG-I, in human head and neck squamous cell carcinoma (HNSCC. RIG-I is abundantly expressed both in poorly-differentiated primary cancer and lymph node metastasis, but not in normal adjacent tissues. Activation of RIG-I by transfection with low dose of 5'-triphosphate RNA (3p-RNA induces low levels of interferon and proinflammatory cytokines and promotes NF-κB- and Akt-dependent cell proliferation, migration and invasion. In contrast, activation of RIG-I by a high dose of 3p-RNA induces robust mitochondria-derived apoptosis accompanied by decreased activation of Akt, which is independent of the interferon and TNFα receptor, but can be rescued by over-expression of constitutively active Akt. Furthermore, co-immunoprecipitation experiments indicate that the CARD domain of RIG-I is essential for inducing apoptosis by interacting with caspase-9. Together, our results reveal a dual role of RIG-I in HNSCC through regulating activation of Akt, in which RIG-I activation by low-dose viral dsRNA increases host cell survival, whereas higher level of RIG-I activation leads to apoptosis. These findings highlight the therapeutic potential of dsRNA mediated RIG-I activation in the treatment of HNSCC.

  1. HPV18 Persistence Impairs Basal and DNA Ligand-Mediated IFN-β and IFN-λ1 Production through Transcriptional Repression of Multiple Downstream Effectors of Pattern Recognition Receptor Signaling.

    Science.gov (United States)

    Albertini, Silvia; Lo Cigno, Irene; Calati, Federica; De Andrea, Marco; Borgogna, Cinzia; Dell'Oste, Valentina; Landolfo, Santo; Gariglio, Marisa

    2018-03-15

    Although it is clear that high-risk human papillomaviruses (HPVs) can selectively infect keratinocytes and persist in the host, it still remains to be unequivocally determined whether they can escape antiviral innate immunity by interfering with pattern recognition receptor (PRR) signaling. In this study, we have assessed the innate immune response in monolayer and organotypic raft cultures of NIKS cells harboring multiple copies of episomal HPV18 (NIKSmcHPV18), which fully recapitulates the persistent state of infection. We show for the first time, to our knowledge, that NIKSmcHPV18, as well as HeLa cells (a cervical carcinoma-derived cell line harboring integrated HPV18 DNA), display marked downregulation of several PRRs, as well as other PRR downstream effectors, such as the adaptor protein stimulator of IFN genes and the transcription factors IRF1 and 7. Importantly, we provide evidence that downregulation of stimulator of IFN genes, cyclic GMP-AMP synthase, and retinoic acid-inducible gene I mRNA levels occurs at the transcriptional level through a novel epigenetic silencing mechanism, as documented by the accumulation of repressive heterochromatin markers seen at the promoter region of these genes. Furthermore, stimulation of NIKSmcHPV18 cells with salmon sperm DNA or poly(deoxyadenylic-deoxythymidylic) acid, two potent inducers of PRR signaling, only partially restored PRR protein expression. Accordingly, the production of IFN-β and IFN-λ 1 was significantly reduced in comparison with the parental NIKS cells, indicating that HPV18 exerts its immunosuppressive activity through downregulation of PRR signaling. Altogether, our findings indicate that high-risk human papillomaviruses have evolved broad-spectrum mechanisms that allow simultaneous depletion of multiple effectors of the innate immunity network, thereby creating an unreactive cellular milieu suitable for viral persistence. Copyright © 2018 by The American Association of Immunologists, Inc.

  2. Lambda Interferon (IFN-gamma), a Type III IFN, is induced by viruses and IFNs and displays potent antiviral activity against select virus infections in vivo

    DEFF Research Database (Denmark)

    Ank, Nina; West, Hans; Bartholdy, C.

    2006-01-01

    Type III interferons (IFNs) (interleukin-28/29 or lambda interferon [IFN-lambda]) are cytokines with IFN-like activities. Here we show that several classes of viruses induce expression of IFN-lambda1 and -lambda2/3 in similar patterns. The IFN-lambdas were-unlike alpha/beta interferon (IFN......-alpha/beta)-induced directly by stimulation with IFN-alpha or -lambda, thus identifying type III IFNs as IFN-stimulated genes. In vitro assays revealed that IFN-lambdas have appreciable antiviral activity against encephalomyocarditis virus (EMCV) but limited activity against herpes simplex virus type 2 (HSV-2), whereas IFN......-alpha potently restricted both viruses. Using three murine models for generalized virus infections, we found that while recombinant IFN-alpha reduced the viral load after infection with EMCV, lymphocytic choriomeningitis virus (LCMV), and HSV-2, treatment with recombinant IFN-lambda in vivo did not affect viral...

  3. Lambda interferon (IFN-lambda), a type III IFN, is induced by viruses and IFNs and displays potent antiviral activity against select virus infections in vivo

    DEFF Research Database (Denmark)

    Ank, Nina; West, Hans; Bartholdy, Christina

    2006-01-01

    Type III interferons (IFNs) (interleukin-28/29 or lambda interferon [IFN-lambda]) are cytokines with IFN-like activities. Here we show that several classes of viruses induce expression of IFN-lambda1 and -lambda2/3 in similar patterns. The IFN-lambdas were-unlike alpha/beta interferon (IFN......-alpha/beta)-induced directly by stimulation with IFN-alpha or -lambda, thus identifying type III IFNs as IFN-stimulated genes. In vitro assays revealed that IFN-lambdas have appreciable antiviral activity against encephalomyocarditis virus (EMCV) but limited activity against herpes simplex virus type 2 (HSV-2), whereas IFN......-alpha potently restricted both viruses. Using three murine models for generalized virus infections, we found that while recombinant IFN-alpha reduced the viral load after infection with EMCV, lymphocytic choriomeningitis virus (LCMV), and HSV-2, treatment with recombinant IFN-lambda in vivo did not affect viral...

  4. Protein A from orange-spotted nervous necrosis virus triggers type I interferon production in fish cell.

    Science.gov (United States)

    Huang, Runqing; Zhou, Qiong; Shi, Yan; Zhang, Jing; He, Jianguo; Xie, Junfeng

    2018-05-04

    Family Nodaviridae consists of two genera: Alphanodavirus and Betanodavirus, and the latter is classified into four genotypes, including red-spotted grouper nervous necrosis virus, tiger puffer nervous necrosis virus, striped jack nervous necrosis virus, and barfin flounder nervous necrosis virus. Type I interferons (IFNs) play a central role in the innate immune system and antiviral responses, and the interactions between IFN and NNV have been investigated in this study. We have found that the RNA-dependent RNA polymerase (RdRp) from orange-spotted nervous necrosis virus (OGNNV), named protein A, was capable of activating IFN promoter in fathead minnow (FHM) cells. Transient expression of protein A was found to induce IFN expression and secretion, endowing FHM cells with anti-tiger frog virus ability. Protein A from SJNNV can also induce IFN expression in FHM cells but that from Flock House virus (FHV), a well-studied representative species of genus Alphanodavirus, cannot. RdRp activity and mitochondrial localization were shown to be required for protein A to induce IFN expression by means of activating IRF3 but not NFκB. Furthermore, DsRNA synthesized in vitro transcription and poly I:C activated IFN promoter activity when transfected into FHM cells, and dsRNA were also detected in NNV-infected cells. We postulated that dsRNA, a PAMP, was produced by protein A, leading to activation of innate immune response. These results suggest that protein As from NNV are the agonists of innate immune response. This is the first work to demonstrate the interaction between NNV protein A and innate immune system, and may help to understand pathogenesis of NNV. Copyright © 2018. Published by Elsevier Ltd.

  5. Drilling rig mast

    Energy Technology Data Exchange (ETDEWEB)

    Bulgakov, E.S.; Barashkov, V.A.; Lebedev, A.I.; Panin, N.M.; Sirotkin, N.V.

    1981-01-07

    A drilling rig mast is proposed that contains a portal with a carrier shaft hinged to it and struts with stays. In order to decrease the time expended in the assembly and dessembly of the drilling rig, the portal is constructed from mobile and immobile parts that are connected together by a ball pivot; the immobile section of the portal has a T-shaped recess for directing the mobile section.

  6. Replacement team of mining drilling rigs

    OpenAIRE

    Hamodi, Hussan; Lundberg, Jan

    2014-01-01

    This paper presents a practical model to calculate the optimal replacement time (ORT) of drilling rigs used in underground mining. As a case study, cost data for drilling rig were collected over four years from a Swedish mine. The cost data include acquisition, operating, maintenance and downtime costs when using a redundant rig. A discount rate is used to determine the value of these costs over time. The study develops an optimisation model to identify the ORT of a mining drilling rig which ...

  7. Autophagy Facilitates IFN-γ-induced Jak2-STAT1 Activation and Cellular Inflammation*

    Science.gov (United States)

    Chang, Yu-Ping; Tsai, Cheng-Chieh; Huang, Wei-Ching; Wang, Chi-Yun; Chen, Chia-Ling; Lin, Yee-Shin; Kai, Jui-In; Hsieh, Chia-Yuan; Cheng, Yi-Lin; Choi, Pui-Ching; Chen, Shun-Hua; Chang, Shih-Ping; Liu, Hsiao-Sheng; Lin, Chiou-Feng

    2010-01-01

    Autophagy is regulated for IFN-γ-mediated antimicrobial efficacy; however, its molecular effects for IFN-γ signaling are largely unknown. Here, we show that autophagy facilitates IFN-γ-activated Jak2-STAT1. IFN-γ induces autophagy in wild-type but not in autophagy protein 5 (Atg5−/−)-deficient mouse embryonic fibroblasts (MEFs), and, autophagy-dependently, IFN-γ induces IFN regulatory factor 1 and cellular inflammatory responses. Pharmacologically inhibiting autophagy using 3-methyladenine, a known inhibitor of class III phosphatidylinositol 3-kinase, confirms these effects. Either Atg5−/− or Atg7−/− MEFs are, independent of changes in IFN-γ receptor expression, resistant to IFN-γ-activated Jak2-STAT1, which suggests that autophagy is important for IFN-γ signal transduction. Lentivirus-based short hairpin RNA for Atg5 knockdown confirmed the importance of autophagy for IFN-γ-activated STAT1. Without autophagy, reactive oxygen species increase and cause SHP2 (Src homology-2 domain-containing phosphatase 2)-regulated STAT1 inactivation. Inhibiting SHP2 reversed both cellular inflammation and the IFN-γ-induced activation of STAT1 in Atg5−/− MEFs. Our study provides evidence that there is a link between autophagy and both IFN-γ signaling and cellular inflammation and that autophagy, because it inhibits the expression of reactive oxygen species and SHP2, is pivotal for Jak2-STAT1 activation. PMID:20592027

  8. IFN-γ-producing Th1-like regulatory T cells may limit acute cellular renal allograft rejection: Paradoxical post-transplantation effects of IFN-γ.

    Science.gov (United States)

    Xu, Xiaoguang; Huang, Haiyan; Wang, Qiang; Cai, Ming; Qian, Yeyong; Han, Yong; Wang, Xinying; Gao, Yu; Yuan, Ming; Xu, Liang; Yao, Chen; Xiao, Li; Shi, Bingyi

    2017-02-01

    IFN-γ is a protypical proinflammatory cytokine that plays a central role in inflammation and acute graft rejection. Accumulating evidence indicates that IFN-γ can exert previously unexpected immunoregulatory activities. However, little is known about the role of IFN-γ secreted by Th1-like regulatory T cells in human kidney transplantation. To determine the function of IFN-γ in acute T cell-mediated renal allograft rejection (ACR), we examined serum cytokine expression profiles in ACR patients by human cytokine multiplex immunoassay and analyzed the cellular origins of IFN-γ in peripheral blood and renal allograft biopsies from ACR cases and controls by flow cytometry and immunohistochemistry, respectively. The results showed significant reduction in serum concentrations of Th1-inducing cytokines IL-12p70 and IFN-γ as well as Th2-related cytokine IL-4 in ACR patients compared with stable controls. However, levels of several Th1-, Th2- and Th17-related cytokines, such as IL-2, TNF-α, TNF-β, IL-12 (p40), IL-10, IL-15, IL-17, IL-21, and IL-23, as well as the frequencies of Th1 and Th17 cell, did not differ between ACR cases and stable controls. Moreover, we found the levels of IFN-γ were correlated with those of the anti-inflammatory factor, IL-1 receptor antagonist (IL-1Ra) in ACR. Notably, the Th1-like Treg cell-to-Foxp3 - Th1 cell ratio was significantly lower in ACR patients compared with that in stable controls. In graft biopsies from ACR patients, Treg cells and Th1-like Treg cells were less abundant than those without ACR. Our study indicates that IFN-γ secreted from Th1-like Treg cells negatively modulates ACR. Copyright © 2016 Elsevier GmbH. All rights reserved.

  9. Interferon-τ increases BoLA-I for implantation during early pregnancy in dairy cows.

    Science.gov (United States)

    Zhu, Zhe; Li, Binbin; Wu, Yue; Wang, Xiao; Deng, GanZhen

    2017-11-10

    Interferon-τ (IFN-τ) signals pregnancy recognition in ruminants. We investigated the effects of IFN-τ produced by embryo trophoblastic cells (ETCs) on expression of bovine leukocyte antigen-I (BoLA-I), a bovine analogue of human MHC-I, in endometrial luminal epithelial cells (EECs) during early pregnancy in dairy cows. Expression of IFN-τ and BoLA-I was increased in endometrial tissues during early pregnancy. Expression of the anti-inflammatory cytokine IL-10 was increased in endometrial tissues, while expression of the pro-inflammatory cytokine IL-6 was decreased, indicating immunosuppression. Progesterone increased IFN-τ expression in EECs. IFN-τ increased p-STAT1 and p-STAT3 levels in EECs, but reduced TRAF3 levels. In addition, IFN-τ increased expression of BoLA-I and IL-10, but decreased expression of IL-6 in EECs. These results indicate that IFN-τ enables stable implantation in dairy cows by increasing expression of BoLA-I, and by immunosuppression mediated by increased IL-10 and decreased IL-6 expression.

  10. Interferon lambda (IFN-λ) efficiently blocks norovirus transmission in a mouse model.

    Science.gov (United States)

    Rocha-Pereira, Joana; Jacobs, Sophie; Noppen, Sam; Verbeken, Eric; Michiels, Thomas; Neyts, Johan

    2018-01-01

    Human noroviruses are highly efficient in person to person transmission thus associated with explosive outbreaks of acute gastroenteritis. Outbreak control is limited to disinfection and isolation measures. Strategies to control the spread of noroviruses should be developed and models to study norovirus transmission will greatly facilitate this. Here, a mouse-to-mouse transmission model, in which mice develop acute murine norovirus (MNV)-induced diarrhea, was used to explore the role of interferon lambda (IFN-λ) in the control of a norovirus infection. Sentinel AG129 mice [deficient in IFN-α/β and IFN-γ receptors] that were co-housed with MNV-infected mice shedding high amounts of virus in their stool, developed a MNV-infection with associated diarrhea. Inoculation of such sentinel mice with an IFN-λ expression plasmid resulted in the production of circulating IFN-λ and upregulation of the expression of IFN-stimulated genes (ISGs) of the gut. Injection of the IFN-λ-expressing plasmid to sentinels prevents MNV-induced disease upon exposure to MNV-infected mice, as well as MNV replication in the small intestine, the associated signs of inflammation and the mounting of a specific IgG-based immune response. This demonstrates that IFN-λ can alone mediate protection against transmission of norovirus. The development of a simple delivery method for IFN-λ could be explored as a strategy to control norovirus outbreaks and protect vulnerable populations such as the elderly and immunocompromised. Copyright © 2017. Published by Elsevier B.V.

  11. Nucleic acid-induced antiviral immunity in invertebrates: an evolutionary perspective.

    Science.gov (United States)

    Wang, Pei-Hui; Weng, Shao-Ping; He, Jian-Guo

    2015-02-01

    Nucleic acids derived from viral pathogens are typical pathogen associated molecular patterns (PAMPs). In mammals, the recognition of viral nucleic acids by pattern recognition receptors (PRRs), which include Toll-like receptors (TLRs) and retinoic acid-inducible gene (RIG)-I-like receptors (RLRs), induces the release of inflammatory cytokines and type I interferons (IFNs) through the activation of nuclear factor κB (NF-κB) and interferon regulatory factor (IRF) 3/7 pathways, triggering the host antiviral state. However, whether nucleic acids can induce similar antiviral immunity in invertebrates remains ambiguous. Several studies have reported that nucleic acid mimics, especially dsRNA mimic poly(I:C), can strongly induce non-specific antiviral immune responses in insects, shrimp, and oyster. This behavior shows multiple similarities to the hallmarks of mammalian IFN responses. In this review, we highlight the current understanding of nucleic acid-induced antiviral immunity in invertebrates. We also discuss the potential recognition and regulatory mechanisms that confer non-specific antiviral immunity on invertebrate hosts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Noncanonical Effects of IRF9 in Intestinal Inflammation: More than Type I and Type III Interferons.

    Science.gov (United States)

    Rauch, Isabella; Rosebrock, Felix; Hainzl, Eva; Heider, Susanne; Majoros, Andrea; Wienerroither, Sebastian; Strobl, Birgit; Stockinger, Silvia; Kenner, Lukas; Müller, Mathias; Decker, Thomas

    2015-07-01

    The interferon (IFN)-stimulated gene factor 3 (ISGF3) transcription factor with its Stat1, Stat2, and interferon regulatory factor 9 (IRF9) subunits is employed for transcriptional responses downstream of receptors for type I interferons (IFN-I) that include IFN-α and IFN-β and type III interferons (IFN-III), also called IFN-λ. Here, we show in a murine model of dextran sodium sulfate (DSS)-induced colitis that IRF9 deficiency protects animals, whereas the combined loss of IFN-I and IFN-III receptors worsens their condition. We explain the different phenotypes by demonstrating a function of IRF9 in a noncanonical transcriptional complex with Stat1, apart from IFN-I and IFN-III signaling. Together, Stat1 and IRF9 produce a proinflammatory activity that overrides the benefits of the IFN-III response on intestinal epithelial cells. Our results further suggest that the CXCL10 chemokine gene is an important mediator of this proinflammatory activity. We thus establish IFN-λ as a potentially anticolitogenic cytokine and propose an important role for IRF9 as a component of noncanonical Stat complexes in the development of colitis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. IFN-γ-producing NKT cells exacerbate sepsis by enhancing C5a generation via IL-10-mediated inhibition of CD55 expression on neutrophils.

    Science.gov (United States)

    Kim, Ji Hyung; Oh, Sae Jin; Ahn, Sehee; Chung, Doo Hyun

    2014-07-01

    A role for NKT cells has been implicated in sepsis, but the mechanism by which NKT cells contribute to sepsis remains unclear. Here, we examined WT and NKT-cell-deficient mice of C57BL/6 background during cecal ligation and puncture-induced sepsis. The levels of C5a, IFN-γ, and IL-10 were higher in the serum and peritoneal fluid of WT mice than in those of CD1d(-/-) mice, while the mortality rate was lower in CD1d(-/-) mice than in WT mice. C5a blockade decreased mortality of WT mice during sepsis, whereas it did not alter that of CD1d(-/-) mice. As assessed by intracellular staining, NKT cells expressed IFN-γ, while neutrophils expressed IL-10. Upon coculture, IL-10-deficient NKT cells enhanced IL-10 production by WT, but not IFN-γR-deficient, neutrophils. Meanwhile, CD1d(-/-) mice exhibited high CD55 expression on neutrophils during sepsis, whereas those cells from WT mice expressed minimal levels of CD55. Recombinant IL-10 administration into CD1d(-/-) mice reduced CD55 expression on neutrophils. Furthermore, adoptive transfer of sorted WT, but not IFN-γ-deficient, NKT cells into CD1d(-/-) mice suppressed CD55 expression on neutrophils, but increased IL-10 and C5a levels. Taken together, IFN-γ-producing NKT cells enhance C5a generation via IL-10-mediated inhibition of CD55 expression on neutrophils, thereby exacerbating sepsis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Hoisting and rigging manual: Uncontrolled document

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-05-01

    This document is a draft copy of a Hoisting and Rigging Manual for the Department of Energy. The manual is divided into ten chapters. The chapter titles follow: terminology and definitions; operator training and qualification; overhead and gantry cranes; mobile cranes; forklift trucks; hoists; hooks; wire rope, slings, and rigging accessories; construction hoisting and rigging equipment requirements; references.

  15. A rigged market

    International Nuclear Information System (INIS)

    Thomas, M.

    2000-01-01

    The mobile rig market remains a unique sector of the global upstream oil and gas industry. Big oil is continuing to emerge blinking from the darkness of its recent cash-starved existence to bask in the glory of a resurgent oil price. But the rig sector is once again lagging behind the pace being set by operators as they open up their wallets for new or delayed exploration and production projects. This paper gives statistics on worldwide count and contracts

  16. Vaccinia Virus Protein C6 Inhibits Type I IFN Signalling in the Nucleus and Binds to the Transactivation Domain of STAT2.

    Directory of Open Access Journals (Sweden)

    Jennifer H Stuart

    2016-12-01

    Full Text Available The type I interferon (IFN response is a crucial innate immune signalling pathway required for defense against viral infection. Accordingly, the great majority of mammalian viruses possess means to inhibit this important host immune response. Here we show that vaccinia virus (VACV strain Western Reserve protein C6, is a dual function protein that inhibits the cellular response to type I IFNs in addition to its published function as an inhibitor of IRF-3 activation, thereby restricting type I IFN production from infected cells. Ectopic expression of C6 inhibits the induction of interferon stimulated genes (ISGs in response to IFNα treatment at both the mRNA and protein level. C6 inhibits the IFNα-induced Janus kinase/signal transducer and activator of transcription (JAK/STAT signalling pathway at a late stage, downstream of STAT1 and STAT2 phosphorylation, nuclear translocation and binding of the interferon stimulated gene factor 3 (ISGF3 complex to the interferon stimulated response element (ISRE. Mechanistically, C6 associates with the transactivation domain of STAT2 and this might explain how C6 inhibits the type I IFN signalling very late in the pathway. During virus infection C6 reduces ISRE-dependent gene expression despite the presence of the viral protein phosphatase VH1 that dephosphorylates STAT1 and STAT2. The ability of a cytoplasmic replicating virus to dampen the immune response within the nucleus, and the ability of viral immunomodulators such as C6 to inhibit multiple stages of the innate immune response by distinct mechanisms, emphasizes the intricacies of host-pathogen interactions and viral immune evasion.

  17. Role of reactive oxygen intermediates in the interferon-mediated depression of hepatic drug metabolism and protective effect of N-acetylcysteine in mice.

    Science.gov (United States)

    Ghezzi, P; Bianchi, M; Gianera, L; Landolfo, S; Salmona, M

    1985-08-01

    Interferon (IFN) and IFN inducers are known to depress hepatic microsomal cytochrome P-450 levels, and the liver toxicity of IFN was reported to be lethal in newborn mice. We have observed that administration to mice of IFN and IFN inducers caused a marked increase in liver xanthine oxidase activity. Because this enzyme is well known to produce reactive oxygen intermediates and cytochrome P-450 was reported to be sensitive to the oxidative damage, we have tested the hypothesis that a free radical mechanism could mediate the depression of cytochrome P-450 levels by IFN. Administration to mice of the IFN inducer polyinosinic-polycytidylic acid (2 mg/kg i.p.) caused a 29 to 52% decrease in liver cytochrome P-450. Concomitant p.o. administration of the free radical scavenger, N-acetylcysteine (as a 2.5% solution in drinking water), or the xanthine oxidase inhibitor, allopurinol (100 mg/kg), protected against the IFN-mediated depression of P-450 kg), protected against the IFN-mediated depression of P-450 levels. The results suggest that an increased endogenous generation of free radicals, possibly due to the induction of xanthine oxidase, is implicated in the IFN-mediated depression of liver drug metabolism. The relevance of these data also extends to cases in which this side effect is observed in pathological situations (e.g., viral diseases and administration of vaccines) associated with an induction of IFN.

  18. Alveolar macrophages and type I IFN in airway homeostasis and immunity.

    Science.gov (United States)

    Divangahi, Maziar; King, Irah L; Pernet, Erwan

    2015-05-01

    Globally, respiratory infections cause more than 4 million deaths per year, with influenza and tuberculosis (TB) in particular being major causes of mortality and morbidity. Although immune cell activation is critical for killing respiratory pathogens, this response must be tightly regulated to effectively control and eliminate invading microorganisms while minimizing immunopathology and maintaining pulmonary function. The distinct microenvironment of the lung is constantly patrolled by alveolar macrophages (Mφ), which are essential for tissue homeostasis, early pathogen recognition, initiation of the local immune response, and resolution of inflammation. Here, we focus on recent advances that have provided insight into the relation between pulmonary Mφ, type I interferon (IFN) signaling, and the delicate balance between protective and pathological immune responses in the lung. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Immunobiotic Bifidobacteria Strains Modulate Rotavirus Immune Response in Porcine Intestinal Epitheliocytes via Pattern Recognition Receptor Signaling.

    Directory of Open Access Journals (Sweden)

    Takamasa Ishizuka

    Full Text Available In this work, we aimed to characterize the antiviral response of an originally established porcine intestinal epithelial cell line (PIE cells by evaluating the molecular innate immune response to rotavirus (RVs. In addition, we aimed to select immunomodulatory bacteria with antiviral capabilities. PIE cells were inoculated with RVs isolated from different host species and the infective titers and the molecular innate immune response were evaluated. In addition, the protection against RVs infection and the modulation of immune response by different lactic acid bacteria (LAB strains was studied. The RVs strains OSU (porcine and UK (bovine effectively infected PIE cells. Our results also showed that RVs infection in PIE cells triggered TLR3-, RIG-I- and MDA-5-mediated immune responses with activation of IRF3 and NF-κB, induction of IFN-β and up-regulation of the interferon stimulated genes MxA and RNase L. Among the LAB strains tested, Bifidobacterium infantis MCC12 and B. breve MCC1274 significantly reduced RVs titers in infected PIE cells. The beneficial effects of both bifidobacteria were associated with reduction of A20 expression, and improvements of IRF-3 activation, IFN-β production, and MxA and RNase L expressions. These results indicate the value of PIE cells for studying RVs molecular innate immune response in pigs and for the selection of beneficial bacteria with antiviral capabilities.

  20. Kallikrein–Kinin System Suppresses Type I Interferon Responses: A Novel Pathway of Interferon Regulation

    Directory of Open Access Journals (Sweden)

    Alecia Seliga

    2018-02-01

    Full Text Available The Kallikrein–Kinin System (KKS, comprised of kallikreins (klks, bradykinins (BKs angiotensin-converting enzyme (ACE, and many other molecules, regulates a number of physiological processes, including inflammation, coagulation, angiogenesis, and control of blood pressure. In this report, we show that KKS regulates Type I IFN responses, thought to be important in lupus pathogenesis. We used CpG (TLR9 ligand, R848 (TLR7 ligand, or recombinant IFN-α to induce interferon-stimulated genes (ISGs and proteins, and observed that this response was markedly diminished by BKs, klk1 (tissue kallikrein, or captopril (an ACE inhibitor. BKs significantly decreased the ISGs induced by TLRs in vitro and in vivo (in normal and lupus-prone mice, and in human PBMCs, especially the induction of Irf7 gene (p < 0.05, the master regulator of Type I IFNs. ISGs induced by IFN-α were also suppressed by the KKS. MHC Class I upregulation, a classic response to Type I IFNs, was reduced by BKs in murine dendritic cells (DCs. BKs decreased phosphorylation of STAT2 molecules that mediate IFN signaling. Among the secreted pro-inflammatory cytokines/chemokines analyzed (IL-6, IL12p70, and CXCL10, the strongest suppressive effect was on CXCL10, a highly Type I IFN-dependent cytokine, upon CpG stimulation, both in normal and lupus-prone DCs. klks that break down into BKs, also suppressed CpG-induced ISGs in murine DCs. Captopril, a drug that inhibits ACE and increases BK, suppressed ISGs, both in mouse DCs and human PBMCs. The effects of BK were reversed with indomethacin (compound that inhibits production of PGE2, suggesting that BK suppression of IFN responses may be mediated via prostaglandins. These results highlight a novel regulatory mechanism in which members of the KKS control the Type I IFN response and suggest a role for modulators of IFNs in the pathogenesis of lupus and interferonopathies.

  1. Aging-related renal injury and inflammation are associated with downregulation of Klotho and induction of RIG-I/NF-κB signaling pathway in senescence-accelerated mice.

    Science.gov (United States)

    Zeng, Yi; Wang, Ping-Han; Zhang, Mao; Du, Jun-Rong

    2016-02-01

    The predominant distribution of the antiaging Klotho protein in both the kidneys and brain may point to its essential role in protecting against dysfunction of the kidney-brain axis during the aging process. Our previous study showed that the downregulation of Klotho was involved in aging-related cognitive impairment in aged senescence-accelerated mouse prone-8 (SAMP8) mice. The present study investigated the potential role of Klotho in aging-associated inflammation and renal injury. Age- and gender-matched groups of SAMP8 mice and their corresponding normal control senescence-accelerated mouse resistant-1 (SAMR1) were used to investigate the potential role of Klotho in aging-associated inflammation and renal injury. Compared with aged SAMR1 controls, early-stage chronic kidney disease (CKD), which is associated with an increase in the urinary albumin-to-creatinine ratio, inflammatory cell infiltration, glomerulosclerosis, and tubulointerstitial fibrosis, was observed in aged SAMP8 mice. Furthermore, the aging-related loss of Klotho-induced activation of the retinoic acid-inducible gene 1/nuclear factor-κB (RIG-I/NF-κB) signaling pathway and subsequent production of the proinflammatory mediators tumor necrosis factor α, interleukin-6, and inducible nitric oxide synthase in the kidneys of aged SAMP8 mice compared with SAMR1 controls. The present results suggest that aging-related inflammation and the development of early-stage CKD are likely associated with the downregulation of Klotho and induction of the RIG-I/NF-κB signaling pathway in 12-month-old SAMP8 mice. Moreover, aged SAMP8 mice with cognitive deficits and renal damage may be a potential mouse model for investigating the kidney-brain axis in the aging process.

  2. Dietary apigenin potentiates the inhibitory effect of interferon-α on cancer cell viability through inhibition of 26S proteasome-mediated interferon receptor degradation

    Directory of Open Access Journals (Sweden)

    Sheng Li

    2016-06-01

    Full Text Available Background: Type I interferons (IFN-α/β have broad and potent immunoregulatory and antiproliferative activities. However, it is still known whether the dietary flavonoids exhibit their antiviral and anticancer properties by modulating the function of type I IFNs. Objective: This study aimed at determining the role of apigenin, a dietary plant flavonoid abundant in common fruits and vegetables, on the type I IFN-mediated inhibition of cancer cell viability. Design: Inhibitory effect of apigenin on human 26S proteasome, a known negative regulator of type I IFN signaling, was evaluated in vitro. Molecular docking was conducted to know the interaction between apigenin and subunits of 26S proteasome. Effects of apigenin on JAK/STAT pathway, 26S proteasome-mediated interferon receptor stability, and cancer cells viability were also investigated. Results: Apigenin was identified to be a potent inhibitor of human 26S proteasome in a cell-based assay. Apigenin inhibited the chymotrypsin-like, caspase-like, and trypsin-like activities of the human 26S proteasome and increased the ubiquitination of endogenous proteins in cells. Results from computational modeling of the potential interactions of apigenin with the chymotrypsin site (β5 subunit, caspase site (β1 subunit, and trypsin site (β2 subunit of the proteasome were consistent with the observed proteasome inhibitory activity. Apigenin enhanced the phosphorylation of signal transducer and activator of transcription proteins (STAT1 and STAT2 and promoted the endogenous IFN-α-regulated gene expression. Apigenin inhibited the IFN-α-stimulated ubiquitination and degradation of type I interferon receptor 1 (IFNAR1. Apigenin also sensitized the inhibitory effect of IFN-α on viability of cervical carcinoma HeLa cells. Conclusion: These results suggest that apigenin potentiates the inhibitory effect of IFN-α on cancer cell viability by activating JAK/STAT signaling pathway through inhibition of 26S

  3. Distinct Upstream Role of Type I IFN Signaling in Hematopoietic Stem Cell-Derived and Epithelial Resident Cells for Concerted Recruitment of Ly-6Chi Monocytes and NK Cells via CCL2-CCL3 Cascade.

    Directory of Open Access Journals (Sweden)

    Erdenebileg Uyangaa

    Full Text Available Type I interferon (IFN-I-dependent orchestrated mobilization of innate cells in inflamed tissues is believed to play a critical role in controlling replication and CNS-invasion of herpes simplex virus (HSV. However, the crucial regulators and cell populations that are affected by IFN-I to establish the early environment of innate cells in HSV-infected mucosal tissues are largely unknown. Here, we found that IFN-I signaling promoted the differentiation of CCL2-producing Ly-6Chi monocytes and IFN-γ/granzyme B-producing NK cells, whereas deficiency of IFN-I signaling induced Ly-6Clo monocytes producing CXCL1 and CXCL2. More interestingly, recruitment of Ly-6Chi monocytes preceded that of NK cells with the levels peaked at 24 h post-infection in IFN-I-dependent manner, which was kinetically associated with the CCL2-CCL3 cascade response. Early Ly-6Chi monocyte recruitment was governed by CCL2 produced from hematopoietic stem cell (HSC-derived leukocytes, whereas NK cell recruitment predominantly depended on CC chemokines produced by resident epithelial cells. Also, IFN-I signaling in HSC-derived leukocytes appeared to suppress Ly-6Ghi neutrophil recruitment to ameliorate immunopathology. Finally, tissue resident CD11bhiF4/80hi macrophages and CD11chiEpCAM+ dendritic cells appeared to produce initial CCL2 for migration-based self-amplification of early infiltrated Ly-6Chi monocytes upon stimulation by IFN-I produced from infected epithelial cells. Ultimately, these results decipher a detailed IFN-I-dependent pathway that establishes orchestrated mobilization of Ly-6Chi monocytes and NK cells through CCL2-CCL3 cascade response of HSC-derived leukocytes and epithelium-resident cells. Therefore, this cascade response of resident-to-hematopoietic-to-resident cells that drives cytokine-to-chemokine-to-cytokine production to recruit orchestrated innate cells is critical for attenuation of HSV replication in inflamed tissues.

  4. Genetic Control of Lyme Arthritis by Borrelia burgdorferi Arthritis-Associated Locus 1 Is Dependent on Localized Differential Production of IFN-β and Requires Upregulation of Myostatin.

    Science.gov (United States)

    Paquette, Jackie K; Ma, Ying; Fisher, Colleen; Li, Jinze; Lee, Sang Beum; Zachary, James F; Kim, Yong Soo; Teuscher, Cory; Weis, Janis J

    2017-11-15

    Previously, using a forward genetic approach, we identified differential expression of type I IFN as a positional candidate for an expression quantitative trait locus underlying Borrelia burgdorferi arthritis-associated locus 1 ( Bbaa1 ). In this study, we show that mAb blockade revealed a unique role for IFN-β in Lyme arthritis development in B6.C3- Bbaa1 mice. Genetic control of IFN-β expression was also identified in bone marrow-derived macrophages stimulated with B. burgdorferi , and it was responsible for feed-forward amplification of IFN-stimulated genes. Reciprocal radiation chimeras between B6.C3- Bbaa1 and C57BL/6 mice revealed that arthritis is initiated by radiation-sensitive cells, but orchestrated by radiation-resistant components of joint tissue. Advanced congenic lines were developed to reduce the physical size of the Bbaa1 interval, and confirmed the contribution of type I IFN genes to Lyme arthritis. RNA sequencing of resident CD45 - joint cells from advanced interval-specific recombinant congenic lines identified myostatin as uniquely upregulated in association with Bbaa1 arthritis development, and myostatin expression was linked to IFN-β production. Inhibition of myostatin in vivo suppressed Lyme arthritis in the reduced interval Bbaa1 congenic mice, formally implicating myostatin as a novel downstream mediator of the joint-specific inflammatory response to B. burgdorferi . Copyright © 2017 by The American Association of Immunologists, Inc.

  5. Development of irradiation rig in HTTR and dosimetry method. I-I type irradiation equipment

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Taiju; Kikuchi, Takayuki [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Miyamoto, Satoshi; Ogura, Kazutomo [Japan Atomic Power Co., Tokyo (Japan)

    2002-12-01

    The High Temperature Engineering Test Reactor (HTTR) is a graphite-moderated, helium gas-cooled test reactor with a maximum power of 30 MW. The HTTR aims not only to establish and upgrade the technological basis for the HTGRs but also to perform the innovative basic research on high temperature engineering with high temperature irradiation fields. It is planned that the HTTR is used to perform various engineering tests such as the safety demonstration test, high temperature test operation and irradiation test with large irradiation fields at high temperatures. This paper describes the design of the I-I type irradiation equipment developed as the first irradiation rig for the HTTR and does the planned dosimetry method at the first irradiation test. It was developed to perform in-pile creep test on a stainless steel with large standard size specimens in the HTTR. It can give great loads on the specimens stably and can control the irradiation temperature precisely. The in-core creep properties on the specimens are measured by newly developed differential transformers and the irradiation condition in the core is monitored by thermocouples and self-powered neutron detectors (SPNDs), continuously. The irradiated neutron fluence is assessed by neutron fluence monitors of small metallic wires after the irradiation. The obtained data at the first irradiation test can strongly be contributed to upgrade the technological basis for the HTGRs, since it is the first direct measurement of the in-core irradiation environments of the HTTR. (author)

  6. Evolution of the DEAD box helicase family in chicken: chickens have no DHX9 ortholog.

    Science.gov (United States)

    Sato, Haruko; Oshiumi, Hiroyuki; Takaki, Hiromi; Hikono, Hirokazu; Seya, Tsukasa

    2015-10-01

    Viral RNA represents a pattern molecule that can be recognized by RNA sensors in innate immunity. Humans and mice possess cytoplasmic DNA/RNA sensors for detecting viral replication. There are a number of DEAD (Asp-Glu-Ala-Asp; DExD/H) box-type helicases in mammals, among which retinoic acid-inducible gene 1 (RIG-I) and melanoma differentiation-associated protein 5 (MDA50) are indispensable for RNA sensing; however, they are functionally supported by a number of sensors that directly bind viral RNA or replicative RNA intermediates to convey signals to RIG-I and MDA5. Some DEAD box helicase members recognize DNA irrespective of the origin. These sensors transmit IFN-inducing signals through adaptors, including mitochondrial antiviral signaling. Viral double-stranded RNAs are reportedly sensed by the helicases DDX1, DDX21, DHX36, DHX9, DDX3, DDX41, LGP2 and DDX60, in addition to RIG-I and MDA5, and induce type I IFNs, thereby blocking viral replication. Humans and mice have all nucleic acid sensors listed here. In the RNA sensing system in chicken, it was found in the present study that most DEAD box helicases are conserved; however, DHX9 is genetically deficient in addition to reported RIG-I. Based on the current genome databases, similar DHX9 deficiency was observed in ducks and several other bird species. Because chicken, but not duck, was found to be deficient in RIG-I, the RNA-sensing system of chicken lacks RIG-I and DHX9 and is thus more fragile than that of duck or mammal. DHX9 may generally compensate for the function of RIG-I and deficiency of DHX9 possibly participates in exacerbations of viral infection such as influenza in chickens. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

  7. Effects of IFN-β1a and IFN-β1b treatment on the expression of cytokines, inducible NOS (NOS type II), and myelin proteins in animal model of multiple sclerosis.

    Science.gov (United States)

    Lubina-Dąbrowska, Natalia; Stepień, Adam; Sulkowski, Grzegorz; Dąbrowska-Bouta, Beata; Langfort, Józef; Chalimoniuk, Małgorzata

    2017-08-01

    The aim of this study was to investigate the effects of interferon (IFN)-β1a and IFN-β1b treatment on inflammatory factors and myelin protein levels in the brain cortex of the Lewis rat experimental autoimmune encephalomyelitis (EAE), animal model of multiple sclerosis. To induce EAE, rat were immunized with inoculums containing spinal cord guinea pig homogenized in phosphate-buffered saline and emulsified in Freund's complete adjuvant containing 110 µg of the appropriate antigen in 100 µl of an emulsion and additionally 4-mg/ml Mycobacterium tuberculosis (H37Ra). The rats were treated three times per week with subcutaneous applications of 300,000 units IFN-β1a or IFN-β1b. The treatments were started 8 days prior to immunization and continued until day 14 after immunization. The rats were killed on the 14th day of the experiment. EAE induced dramatic increase in interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-concentrations and inducible nitric oxide synthase (iNOS) expression in the brain, which closely corresponded to the course of neurological symptoms and the loss of weight. Both IFN-β1b and IFN-β1a treatments inhibited the pro-inflammatory cytokines (IL-6, IL-1β, TNF-α and IFN-γ), decreased the activation of astrocytes, increased the myelin protein level in the brain cortex, and improved the neurological status of EAE rats by different mechanisms; IFN-β1a reduced iNOS expression, at least in part, by the enhancement of IL-10, while IFN-β1b diminished IL-10 concentration and did not decrease EAE-induced iNOS expression.

  8. Evasion of IFN-γ signaling by Francisella novicida is dependent upon Francisella outer membrane protein C.

    Directory of Open Access Journals (Sweden)

    Kalyan C Nallaparaju

    2011-03-01

    Full Text Available Francisella tularensis is a Gram-negative facultative intracellular bacterium and the causative agent of the lethal disease tularemia. An outer membrane protein (FTT0918 of F. tularensis subsp. tularensis has been identified as a virulence factor. We generated a F. novicida (F. tularensis subsp. novicida FTN_0444 (homolog of FTT0918 fopC mutant to study the virulence-associated mechanism(s of FTT0918.The ΔfopC strain phenotype was characterized using immunological and biochemical assays. Attenuated virulence via the pulmonary route in wildtype C57BL/6 and BALB/c mice, as well as in knockout (KO mice, including MHC I, MHC II, and µmT (B cell deficient, but not in IFN-γ or IFN-γR KO mice was observed. Primary bone marrow derived macrophages (BMDM prepared from C57BL/6 mice treated with rIFN-γ exhibited greater inhibition of intracellular ΔfopC than wildtype U112 strain replication; whereas, IFN-γR KO macrophages showed no IFN-γ-dependent inhibition of ΔfopC replication. Moreover, phosphorylation of STAT1 was downregulated by the wildtype strain, but not the fopC mutant, in rIFN-γ treated macrophages. Addition of NG-monomethyl-L-arginine, an NOS inhibitor, led to an increase of ΔfopC replication to that seen in the BMDM unstimulated with rIFN-γ. Enzymatic screening of ΔfopC revealed aberrant acid phosphatase activity and localization. Furthermore, a greater abundance of different proteins in the culture supernatants of ΔfopC than that in the wildtype U112 strain was observed.F. novicida FopC protein facilitates evasion of IFN-γ-mediated immune defense(s by down-regulation of STAT1 phosphorylation and nitric oxide production, thereby promoting virulence. Additionally, the FopC protein also may play a role in maintaining outer membrane stability (integrity facilitating the activity and localization of acid phosphatases and other F. novicida cell components.

  9. New World hantaviruses activate IFNlambda production in type I IFN-deficient vero E6 cells.

    Directory of Open Access Journals (Sweden)

    Joseph Prescott

    Full Text Available Hantaviruses indigenous to the New World are the etiologic agents of hantavirus cardiopulmonary syndrome (HCPS. These viruses induce a strong interferon-stimulated gene (ISG response in human endothelial cells. African green monkey-derived Vero E6 cells are used to propagate hantaviruses as well as many other viruses. The utility of the Vero E6 cell line for virus production is thought to owe to their lack of genes encoding type I interferons (IFN, rendering them unable to mount an efficient innate immune response to virus infection. Interferon lambda, a more recently characterized type III IFN, is transcriptionally controlled much like the type I IFNs, and activates the innate immune system in a similar manner.We show that Vero E6 cells respond to hantavirus infection by secreting abundant IFNlambda. Three New World hantaviruses were similarly able to induce IFNlambda expression in this cell line. The IFNlambda contained within virus preparations generated with Vero E6 cells independently activates ISGs when used to infect several non-endothelial cell lines, whereas innate immune responses by endothelial cells are specifically due to viral infection. We show further that Sin Nombre virus replicates to high titer in human hepatoma cells (Huh7 without inducing ISGs.Herein we report that Vero E6 cells respond to viral infection with a highly active antiviral response, including secretion of abundant IFNlambda. This cytokine is biologically active, and when contained within viral preparations and presented to human epithelioid cell lines, results in the robust activation of innate immune responses. We also show that both Huh7 and A549 cell lines do not respond to hantavirus infection, confirming that the cytoplasmic RNA helicase pathways possessed by these cells are not involved in hantavirus recognition. We demonstrate that Vero E6 actively respond to virus infection and inhibiting IFNlambda production in these cells might increase their utility

  10. Technology trends, energy prices affect worldwide rig activity

    International Nuclear Information System (INIS)

    Rappold, K.

    1995-01-01

    The major worldwide offshore rig markets have improved slightly this year, while the onshore markets generally lagged slightly. Offshore rig utilization rates have remained strong worldwide, with some areas reaching nearly 100%. Total worldwide offshore rig (jack ups, semisubmersible, drillships, submersibles, and barges) utilization was about 86%. Offshore drilling activity is driven primarily by oil and natural gas price expectations. Natural gas prices tend to drive North American offshore drilling activity, including the shallow waters in the Gulf of Mexico. International offshore drilling activity and deepwater projects in the Gulf of Mexico are more closely tied to oil prices. The paper discusses US rig count, directional drilling activity, jack up rig demand, semisubmersibles demand, rig replacement costs, and new construction

  11. Biogenesis of non-structural protein 1 (nsp1) and nsp1-mediated type I interferon modulation in arteriviruses

    Energy Technology Data Exchange (ETDEWEB)

    Han, Mingyuan; Kim, Chi Yong [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Avenue, Urbana, IL 61802 (United States); Rowland, Raymond R.R.; Fang, Ying [Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, KS 66506 (United States); Kim, Daewoo [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Avenue, Urbana, IL 61802 (United States); Yoo, Dongwan, E-mail: dyoo@illinois.edu [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Avenue, Urbana, IL 61802 (United States)

    2014-06-15

    Type I interferons (IFNs-α/β) play a key role for the antiviral state of host, and the porcine arterivirus; porcine reproductive and respiratory syndrome virus (PRRSV), has been shown to down-regulate the production of IFNs during infection. Non-structural protein (nsp) 1 of PRRSV has been identified as a viral IFN antagonist, and the nsp1α subunit of nsp1 has been shown to degrade the CREB-binding protein (CBP) and to inhibit the formation of enhanceosome thus resulting in the suppression of IFN production. The study was expanded to other member viruses in the family Arteriviridae: equine arteritis virus (EAV), murine lactate dehydrogenase-elevating virus (LDV), and simian hemorrhagic fever virus (SHFV). While PRRSV–nsp1 and LDV–nsp1 were auto-cleaved to produce the nsp1α and nsp1β subunits, EAV–nsp1 remained uncleaved. SHFV–nsp1 was initially predicted to be cleaved to generate three subunits (nsp1α, nsp1β, and nsp1γ), but only two subunits were generated as SHFV–nsp1αβ and SHFV–nsp1γ. The papain-like cysteine protease (PLP) 1α motif in nsp1α remained inactive for SHFV, and only the PLP1β motif of nsp1β was functional to generate SHFV–nsp1γ subunit. All subunits of arterivirus nsp1 were localized in the both nucleus and cytoplasm, but PRRSV–nsp1β, LDV–nsp1β, EAV–nsp1, and SHFV–nsp1γ were predominantly found in the nucleus. All subunits of arterivirus nsp1 contained the IFN suppressive activity and inhibited both interferon regulatory factor 3 (IRF3) and NF-κB mediated IFN promoter activities. Similar to PRRSV–nsp1α, CBP degradation was evident in cells expressing LDV–nsp1α and SHFV–nsp1γ, but no such degradation was observed for EAV–nsp1. Regardless of CBP degradation, all subunits of arterivirus nsp1 suppressed the IFN-sensitive response element (ISRE)-promoter activities. Our data show that the nsp1-mediated IFN modulation is a common strategy for all arteriviruses but their mechanism of action may differ

  12. Interferon Induction by RNA Viruses and Antagonism by Viral Pathogens

    Directory of Open Access Journals (Sweden)

    Yuchen Nan

    2014-12-01

    Full Text Available Interferons are a group of small proteins that play key roles in host antiviral innate immunity. Their induction mainly relies on host pattern recognition receptors (PRR. Host PRR for RNA viruses include Toll-like receptors (TLR and retinoic acid-inducible gene I (RIG-I like receptors (RLR. Activation of both TLR and RLR pathways can eventually lead to the secretion of type I IFNs, which can modulate both innate and adaptive immune responses against viral pathogens. Because of the important roles of interferons, viruses have evolved multiple strategies to evade host TLR and RLR mediated signaling. This review focuses on the mechanisms of interferon induction and antagonism of the antiviral strategy by RNA viruses.

  13. Ultrasound-mediated interferon β gene transfection inhibits growth of malignant melanoma

    International Nuclear Information System (INIS)

    Yamaguchi, Kazuki; Feril, Loreto B.; Tachibana, Katsuro; Takahashi, Akira; Matsuo, Miki; Endo, Hitomi; Harada, Yoshimi; Nakayama, Juichiro

    2011-01-01

    Highlights: → Successful ultrasound-mediated transfection of melanoma (C32) cells with IFN-β genes both in vitro and in vivo. → Ultrasound-mediated IFN-β transfection inhibited proliferation of melanoma cells in vitro. → Ultrasound-mediated IFN-β transfection inhibited melanoma tumor growth in vivo. -- Abstract: We investigated the effects of ultrasound-mediated transfection (sonotransfection) of interferon β (IFN-β) gene on melanoma (C32) both in vitro and in vivo. C32 cells were sonotransfected with IFN-β in vitro. Subcutaneous C32 tumors in mice were sonicated weekly immediately after intra-tumor injection with IFN-β genes mixed with microbubbles. Successful sonotransfection with IFN-β gene in vitro was confirmed by ELISA, which resulted in C32 growth inhibition. In vivo, the growth ratio of tumors transfected with IFN-β gene was significantly lower than the other experimental groups. These results may lead to a new method of treatment against melanoma and other hard-to-treat cancers.

  14. Type I and Type III Interferons Display Different Dependency on Mitogen-Activated Protein Kinases to Mount an Antiviral State in the Human Gut.

    Science.gov (United States)

    Pervolaraki, Kalliopi; Stanifer, Megan L; Münchau, Stephanie; Renn, Lynnsey A; Albrecht, Dorothee; Kurzhals, Stefan; Senís, Elena; Grimm, Dirk; Schröder-Braunstein, Jutta; Rabin, Ronald L; Boulant, Steeve

    2017-01-01

    Intestinal epithelial cells (IECs) are constantly exposed to commensal flora and pathogen challenges. How IECs regulate their innate immune response to maintain gut homeostasis remains unclear. Interferons (IFNs) are cytokines produced during infections. While type I IFN receptors are ubiquitously expressed, type III IFN receptors are expressed only on epithelial cells. This epithelium specificity strongly suggests exclusive functions at epithelial surfaces, but the relative roles of type I and III IFNs in the establishment of an antiviral innate immune response in human IECs are not clearly defined. Here, we used mini-gut organoids to define the functions of types I and III IFNs to protect the human gut against viral infection. We show that primary non-transformed human IECs, upon viral challenge, upregulate the expression of both type I and type III IFNs at the transcriptional level but only secrete type III IFN in the supernatant. However, human IECs respond to both type I and type III IFNs by producing IFN-stimulated genes that in turn induce an antiviral state. Using genetic ablation of either type I or type III IFN receptors, we show that either IFN can independently restrict virus infection in human IECs. Importantly, we report, for the first time, differences in the mechanisms by which each IFN establishes the antiviral state. Contrary to type I IFN, the antiviral activity induced by type III IFN is strongly dependent on the mitogen-activated protein kinases signaling pathway, suggesting a pathway used by type III IFNs that non-redundantly contributes to the antiviral state. In conclusion, we demonstrate that human intestinal epithelial cells specifically regulate their innate immune response favoring type III IFN-mediated signaling, which allows for efficient protection against pathogens without producing excessive inflammation. Our results strongly suggest that type III IFN constitutes the frontline of antiviral response in the human gut. We propose that

  15. Rigged Hilbert spaces for chaotic dynamical systems

    International Nuclear Information System (INIS)

    Suchanecki, Z.; Antoniou, I.; Bandtlow, O.F.

    1996-01-01

    We consider the problem of rigging for the Koopman operators of the Renyi and the baker maps. We show that the rigged Hilbert space for the Renyi maps has some of the properties of a strict inductive limit and give a detailed description of the rigged Hilbert space for the baker maps. copyright 1996 American Institute of Physics

  16. Learning Inverse Rig Mappings by Nonlinear Regression.

    Science.gov (United States)

    Holden, Daniel; Saito, Jun; Komura, Taku

    2017-03-01

    We present a framework to design inverse rig-functions-functions that map low level representations of a character's pose such as joint positions or surface geometry to the representation used by animators called the animation rig. Animators design scenes using an animation rig, a framework widely adopted in animation production which allows animators to design character poses and geometry via intuitive parameters and interfaces. Yet most state-of-the-art computer animation techniques control characters through raw, low level representations such as joint angles, joint positions, or vertex coordinates. This difference often stops the adoption of state-of-the-art techniques in animation production. Our framework solves this issue by learning a mapping between the low level representations of the pose and the animation rig. We use nonlinear regression techniques, learning from example animation sequences designed by the animators. When new motions are provided in the skeleton space, the learned mapping is used to estimate the rig controls that reproduce such a motion. We introduce two nonlinear functions for producing such a mapping: Gaussian process regression and feedforward neural networks. The appropriate solution depends on the nature of the rig and the amount of data available for training. We show our framework applied to various examples including articulated biped characters, quadruped characters, facial animation rigs, and deformable characters. With our system, animators have the freedom to apply any motion synthesis algorithm to arbitrary rigging and animation pipelines for immediate editing. This greatly improves the productivity of 3D animation, while retaining the flexibility and creativity of artistic input.

  17. Endurance test on IR rig for RI production

    International Nuclear Information System (INIS)

    Chung, Heung June; Youn, Y. J.; Han, H. S.; Hong, S. B.; Cho, Y. G.; Ryu, J. S.

    2000-12-01

    This report presents the pressure drop, vibration and endurance test results for IR rig for RI production which were desigened and fabricated by KAERI. From the pressure drop test results, it is noted that the flow rate through the IR rig corresponding to the pressure drop of 200 kPa is measured to be about 3.12 kg/sec. Vibration frequency for the IR rig ranges from 13 to 17 Hz. RMS(Root Mean Square) displacement for the IR rig is less than 30 μm, and the maximum displacement is less than 110μm. These experimental results show that the design criteria of IR rig meet the HANARO limit conditions. Endurance test results show that the appreciable fretting wear for the IR rig does not occur, however tiny trace of wear between contact points is observed

  18. Type I Interferon Induction by Neisseria gonorrhoeae: Dual Requirement of Cyclic GMP-AMP Synthase and Toll-like Receptor 4.

    Science.gov (United States)

    Andrade, Warrison A; Agarwal, Sarika; Mo, Shunyan; Shaffer, Scott A; Dillard, Joseph P; Schmidt, Tobias; Hornung, Veit; Fitzgerald, Katherine A; Kurt-Jones, Evelyn A; Golenbock, Douglas T

    2016-06-14

    The innate immune system is the first line of defense against Neisseria gonorrhoeae (GC). Exposure of cells to GC lipooligosaccharides induces a strong immune response, leading to type I interferon (IFN) production via TLR4/MD-2. In addition to living freely in the extracellular space, GC can invade the cytoplasm to evade detection and elimination. Double-stranded DNA introduced into the cytosol binds and activates the enzyme cyclic-GMP-AMP synthase (cGAS), which produces 2'3'-cGAMP and triggers STING/TBK-1/IRF3 activation, resulting in type I IFN expression. Here, we reveal a cytosolic response to GC DNA that also contributes to type I IFN induction. We demonstrate that complete IFN-β induction by live GC depends on both cGAS and TLR4. Type I IFN is detrimental to the host, and dysregulation of iron homeostasis genes may explain lower bacteria survival in cGAS(-/-) and TLR4(-/-) cells. Collectively, these observations reveal cooperation between TLRs and cGAS in immunity to GC infection. Copyright © 2016. Published by Elsevier Inc.

  19. Type I Interferon Induction by Neisseria gonorrhoeae: Dual Requirement of Cyclic GMP-AMP Synthase and Toll-like Receptor 4

    Directory of Open Access Journals (Sweden)

    Warrison A. Andrade

    2016-06-01

    Full Text Available The innate immune system is the first line of defense against Neisseria gonorrhoeae (GC. Exposure of cells to GC lipooligosaccharides induces a strong immune response, leading to type I interferon (IFN production via TLR4/MD-2. In addition to living freely in the extracellular space, GC can invade the cytoplasm to evade detection and elimination. Double-stranded DNA introduced into the cytosol binds and activates the enzyme cyclic-GMP-AMP synthase (cGAS, which produces 2′3′-cGAMP and triggers STING/TBK-1/IRF3 activation, resulting in type I IFN expression. Here, we reveal a cytosolic response to GC DNA that also contributes to type I IFN induction. We demonstrate that complete IFN-β induction by live GC depends on both cGAS and TLR4. Type I IFN is detrimental to the host, and dysregulation of iron homeostasis genes may explain lower bacteria survival in cGAS−/− and TLR4−/− cells. Collectively, these observations reveal cooperation between TLRs and cGAS in immunity to GC infection.

  20. Adenovirus Vector-Derived VA-RNA-Mediated Innate Immune Responses

    Directory of Open Access Journals (Sweden)

    Hiroyuki Mizuguchi

    2011-07-01

    Full Text Available The major limitation of the clinical use of replication-incompetent adenovirus (Ad vectors is the interference by innate immune responses, including induction of inflammatory cytokines and interferons (IFN, following in vivo application of Ad vectors. Ad vector-induced production of inflammatory cytokines and IFNs also results in severe organ damage and efficient induction of acquired immune responses against Ad proteins and transgene products. Ad vector-induced innate immune responses are triggered by the recognition of Ad components by pattern recognition receptors (PRRs. In order to reduce the side effects by Ad vector-induced innate immune responses and to develop safer Ad vectors, it is crucial to clarify which PRRs and which Ad components are involved in Ad vector-induced innate immune responses. Our group previously demonstrated that myeloid differentiating factor 88 (MyD88 and toll-like receptor 9 (TLR9 play crucial roles in the Ad vector-induced inflammatory cytokine production in mouse bone marrow-derived dendritic cells. Furthermore, our group recently found that virus associated-RNAs (VA-RNAs, which are about 160 nucleotide-long non-coding small RNAs encoded in the Ad genome, are involved in IFN production through the IFN-β promoter stimulator-1 (IPS-1-mediated signaling pathway following Ad vector transduction. The aim of this review is to highlight the Ad vector-induced innate immune responses following transduction, especially VA-RNA-mediated innate immune responses. Our findings on the mechanism of Ad vector-induced innate immune responses should make an important contribution to the development of safer Ad vectors, such as an Ad vector lacking expression of VA-RNAs.

  1. Apoptotic-cell-derived membrane microparticles and IFN-α induce an inflammatory immune response.

    Science.gov (United States)

    Niessen, Anna; Heyder, Petra; Krienke, Stefan; Blank, Norbert; Tykocinski, Lars-Oliver; Lorenz, Hanns-Martin; Schiller, Martin

    2015-07-15

    A dysregulation in the clearance of apoptotic material is considered a major pathogenetic factor for the emergence of autoimmune diseases. Apoptotic-cell-derived membrane microparticles (AdMPs), which are released from the cell surface during apoptosis, have been implicated in the pathogenesis of autoimmunity. Also of importance are cytokines, such as interferon-α (IFN-α), which is known to be a major player in patients with systemic lupus erythematosus (SLE). This study investigates the combined effect of AdMPs and IFN-α on professional phagocytes. In the presence of IFN-α, phagocytosis of AdMPs by human monocytes was significantly increased in a dose-dependent manner. The combination of AdMPs and raised IFN-α concentrations resulted in an increase in the secretion of pro-inflammatory cytokines and an upregulation of surface molecule expression involved in antigen uptake. In addition, macrophage polarisation was shifted towards a more inflammatory type of cell. The synergism between IFN-α and AdMPs seemed to be mediated by an upregulation of phosphorylated STAT1. Our results indicate that IFN-α, together with AdMPs, amplify the initiation and maintenance of inflammation. This mechanism might especially play a crucial role in disorders with a defective clearance of apoptotic material. © 2015. Published by The Company of Biologists Ltd.

  2. Role of type I interferon receptor signaling on NK cell development and functions.

    Directory of Open Access Journals (Sweden)

    Jean Guan

    Full Text Available Type I interferons (IFN are unique cytokines transcribed from intronless genes. They have been extensively studied because of their anti-viral functions. The anti-viral effects of type I IFN are mediated in part by natural killer (NK cells. However, the exact contribution of type I IFN on NK cell development, maturation and activation has been somewhat difficult to assess. In this study, we used a variety of approaches to define the consequences of the lack of type I interferon receptor (IFNAR signaling on NK cells. Using IFNAR deficient mice, we found that type I IFN affect NK cell development at the pre-pro NK stage. We also found that systemic absence of IFNAR signaling impacts NK cell maturation with a significant increase in the CD27+CD11b+ double positive (DP compartment in all organs. However, there is tissue specificity, and only in liver and bone marrow is the maturation defect strictly dependent on cell intrinsic IFNAR signaling. Finally, using adoptive transfer and mixed bone marrow approaches, we also show that cell intrinsic IFNAR signaling is not required for NK cell IFN-γ production in the context of MCMV infection. Taken together, our studies provide novel insights on how type I IFN receptor signaling regulates NK cell development and functions.

  3. Lol p I-induced IL-4 and IFN-gamma production by peripheral blood mononuclear cells of atopic and nonatopic subjects during and out of the pollen season.

    Science.gov (United States)

    Gagnon, R; Akoum, A; Hébert, J

    1993-04-01

    The reciprocal effects of IL-4 and IFN-gamma on IgE synthesis have been well established. It has also been shown that these two lymphokines are secreted by different subsets of CD4+ T cells (TH1 and TH2), and that TH2 helper T lymphocytes could be involved in the pathophysiology of allergic diseases. But little is known about the effects of an allergen on the profile of lymphokine synthesis by human peripheral blood mononuclear cells (PBMCs) of allergic and nonallergic subjects. We studied the production of IL-4 and IFN-gamma by PBMCs of atopic and nonatopic donors after in vitro stimulation by the group 1 allergen from Lolium perenne pollen (Lol p I), during and out of the grass pollen season. On natural exposure to pollen, Lol p I-induced IL-4 production was observed only with atopic donors (6 of 8), whereas the synthesis of IFN-gamma was observed for all nonatopic donors (7 of 7) and most allergic patients (5 of 7). At the time of the study, higher amounts of IFN-gamma were produced by PBMCs of nonatopic donors than by PBMCs of atopic patients. Out of the pollen season the production of IL-4 was not observed either by atopic (n = 11) or by nonatopic subjects (n = 5). On the other hand, IFN-gamma was produced by PBMCs of most subjects (atopic, 10 of 11; nonatopic, 5 of 5), but at the time of the study no difference was observed between the two groups. These results show that Lol p I induces different profiles of IL-4 and IFN-gamma production by PBMCs of atopic and nonatopic subjects. In atopic subjects this profile of lymphokine synthesis is influenced by the natural exposure to pollen, which is in keeping with the seasonal rise of IgE antibodies.

  4. Injecting rabies immunoglobulin (RIG) into wounds only: A significant saving of lives and costly RIG.

    Science.gov (United States)

    Bharti, Omesh Kumar; Madhusudana, Shampur Narayan; Wilde, Henry

    2017-04-03

    An increasing number of dog bite victims were being presented to public hospitals in Himachal Pradesh in 2014 amidst virtual non availability of any rabies immunoglobulin (RIG). Only a small quantity of equine rabies immunoglobulin (eRIG) was available from the government owned Central Research Institute (CRI) Kasauli. This available eRIG was used in 269 patients as an emergency response and only for local infiltration of severe bite wounds by suspected rabid dogs. This was followed by rabies vaccination, using the WHO approved intra-dermal Thai Red Cross Society vaccination schedule. A subgroup of 26 patients were later identified who had been severely bitten by laboratory confirmed rabid dogs. They were followed for more than one year and all were found to be alive.

  5. IFN-γ priming of macrophages represses a part of the inflammatory program and attenuates neutrophil recruitment

    NARCIS (Netherlands)

    Hoeksema, Marten A.; Scicluna, Brendon P.; Boshuizen, Marieke C. S.; van der Velden, Saskia; Neele, Annette E.; van den Bossche, Jan; Matlung, Hanke L.; van den Berg, Timo K.; Goossens, Pieter; de Winther, Menno P. J.

    2015-01-01

    Macrophages form a heterogeneous population of immune cells, which is critical for both the initiation and resolution of inflammation. They can be skewed to a proinflammatory subtype by the Th1 cytokine IFN-γ and further activated with TLR triggers, such as LPS. In this work, we investigated the

  6. IFN signaling: how a non-canonical model led to the development of IFN mimetics

    Directory of Open Access Journals (Sweden)

    Howard M Johnson

    2013-07-01

    Full Text Available The classical model of cytokine signaling dominates our view of specific gene activation by cytokines such as the interferons (IFNs. The importance of the model extends beyond cytokines and applies to hormones such as growth hormone (GH and insulin, and growth factors such as epidermal growth factor (EGF and fibroblast growth factor (FGF. According to this model, ligand activates the cell via interaction with the extracellular domain of the receptor. This results in activation of receptor or receptor-associated tyrosine kinases, primarily of the Janus kinase (JAK family, phosphorylation and dimerization of the STAT transcription factors, which dissociate from the receptor cytoplasmic domain and translocate to the nucleus. This view ascribes no further role to the ligand, JAK kinase, or receptor in either specific gene activation or the associated epigenetic events. The presence of dimeric STATs in the nucleus essentially explains it all. Our studies have resulted in the development of a non-canonical, more complex model of IFNγ signaling that is akin to that of steroid hormone/steroid receptor signaling. We have shown that ligand, receptor, activated JAKs and STATs are associated with specific gene activation, where the receptor subunit IFNGR1 functions as a co-transcription factor and the JAKs are involved in associated epigenetic events. We found that the type I IFN system functions similarly. The fact that GH receptor, insulin receptor, EGF receptor, and FGF receptor undergo nuclear translocation upon ligand binding suggests that they may also function similarly. The steroid hormone/steroid receptor nature of type I and II IFN signaling provides insight into the specificity of signaling by members of cytokine families. The non-canonical model could also provide better understanding to more complex cytokine families such as those of IL-2 and IL-12, whose members often use the same JAKs and STATs, but also have different functions and

  7. Differential Regulation of Interferon Responses by Ebola and Marburg Virus VP35 Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Megan R.; Liu, Gai; Mire, Chad E.; Sureshchandra, Suhas; Luthra, Priya; Yen, Benjamin; Shabman, Reed S.; Leung, Daisy W.; Messaoudi, Ilhem; Geisbert, Thomas W.; Amarasinghe, Gaya K.; Basler, Christopher F.

    2016-02-11

    Suppression of innate immune responses during filoviral infection contributes to disease severity. Ebola (EBOV) and Marburg (MARV) viruses each encode a VP35 protein that suppresses RIG-I-like receptor signaling and interferon-α/β (IFN-α/β) production by several mechanisms, including direct binding to double stranded RNA (dsRNA). Here, we demonstrate that in cell culture, MARV infection results in a greater upregulation of IFN responses as compared to EBOV infection. This correlates with differences in the efficiencies by which EBOV and MARV VP35s antagonize RIG-I signaling. Furthermore, structural and biochemical studies suggest that differential recognition of RNA elements by the respective VP35 C-terminal IFN inhibitory domain (IID) rather than affinity for RNA by the respective VP35s is critical for this observation. Our studies reveal functional differences in EBOV versus MARV VP35 RNA binding that result in unexpected differences in the host response to deadly viral pathogens.

  8. A bacterial cyclic dinucleotide activates the cytosolic surveillance pathway and mediates innate resistance to tuberculosis.

    Science.gov (United States)

    Dey, Bappaditya; Dey, Ruchi Jain; Cheung, Laurene S; Pokkali, Supriya; Guo, Haidan; Lee, Jong-Hee; Bishai, William R

    2015-04-01

    Detection of cyclic-di-adenosine monophosphate (c-di-AMP), a bacterial second messenger, by the host cytoplasmic surveillance pathway (CSP) is known to elicit type I interferon (IFN) responses, which are crucial to antimicrobial defense. However, the mechanisms and role of c-di-AMP signaling in Mycobacterium tuberculosis virulence remain unclear. Here we show that resistance to tuberculosis requires CSP-mediated detection of c-di-AMP produced by M. tuberculosis and that levels of c-di-AMP modulate the fate of infection. We found that a di-adenylate cyclase (disA or dacA)-overexpressing M. tuberculosis strain that secretes excess c-di-AMP activates the interferon regulatory factor (IRF) pathway with enhanced levels of IFN-β, elicits increased macrophage autophagy, and exhibits substantial virulence attenuation in mice. We show that c-di-AMP-mediated IFN-β induction during M. tuberculosis infection requires stimulator of interferon genes (STING)-signaling. We observed that c-di-AMP induction of IFN-β is independent of the cytosolic nucleic acid receptor cyclic GMP-AMP (cGAMP) synthase (cGAS), but cGAS nevertheless contributes substantially to the overall IFN-β response to M. tuberculosis infection. In sum, our results reveal c-di-AMP to be a key mycobacterial pathogen-associated molecular pattern (PAMP) driving host type I IFN responses and autophagy. These findings suggest that modulating the levels of this small molecule may lead to novel immunotherapeutic strategies against tuberculosis.

  9. Loss of PTEN causes SHP2 activation, making lung cancer cells unresponsive to IFN

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chia-Ling [Translational Research Center, Taipei Medical University, Taipei 110, Taiwan (China); Chiang, Tzu-Hui; Tseng, Po-Chun [Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Wang, Yu-Chih [Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Lin, Chiou-Feng, E-mail: cflin2014@tmu.edu.tw [Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China)

    2015-10-23

    Src homology-2 domain-containing phosphatase (SHP) 2, an oncogenic phosphatase, inhibits type II immune interferon (IFN)-γ signaling by subverting signal transducers and activators of transcription 1 tyrosine phosphorylation and activation. For cancer immunoediting, this study aimed to investigate the decrease of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), a tumor suppressor protein, leading to cellular impairment of IFN-γ signaling. In comparison with human lung adenocarcinoma A549 cells, the natural PTEN loss in another human lung adenocarcinoma line, PC14PE6/AS2 cells, presents reduced responsiveness in IFN-γ-induced IFN regulatory factor 1 activation and CD54 expression. Artificially silencing PTEN expression in A549 cells also caused cells to be unresponsive to IFN-γ without affecting IFN-γ receptor expression. IFN-γ-induced inhibition of cell proliferation and cytotoxicity were demonstrated in A549 cells but were defective in PC14PE6/AS2 cells and in PTEN-deficient A549 cells. Aberrant activation of SHP2 by ROS was specifically shown in PC14PE6/AS2 cells and PTEN-deficient A549 cells. Inhibiting ROS and SHP2 rescued cellular responses to IFN-γ-induced cytotoxicity and inhibition of cell proliferation in PC14PE6/AS2 cells. These results demonstrate that a decrease in PTEN facilitates ROS/SHP2 signaling, causing lung cancer cells to become unresponsive to IFN-γ. - Highlights: • This study demonstrates that PTEN decrease causes cellular unresponsive to IFN-γ. • Lung cancer cells with PTEN deficiency show unresponsive to IFN-γ signaling. • PTEN decrease inhibits IFN-γ-induced CD54, cell proliferation inhibition, and cytotoxicity. • ROS-mediated SHP2 activation makes PTEN-deficient cells unresponsive to IFN-γ.

  10. Experimental Neuromyelitis Optica Induces a Type I Interferon Signature in the Spinal Cord

    Science.gov (United States)

    Kaufmann, Nathalie; Zeka, Bleranda; Schanda, Kathrin; Fujihara, Kazuo; Illes, Zsolt; Dahle, Charlotte; Reindl, Markus; Lassmann, Hans; Bradl, Monika

    2016-01-01

    Neuromyelitis optica (NMO) is an acute inflammatory disease of the central nervous system (CNS) which predominantly affects spinal cord and optic nerves. Most patients harbor pathogenic autoantibodies, the so-called NMO-IgGs, which are directed against the water channel aquaporin 4 (AQP4) on astrocytes. When these antibodies gain access to the CNS, they mediate astrocyte destruction by complement-dependent and by antibody-dependent cellular cytotoxicity. In contrast to multiple sclerosis (MS) patients who benefit from therapies involving type I interferons (I-IFN), NMO patients typically do not profit from such treatments. How is I-IFN involved in NMO pathogenesis? To address this question, we made gene expression profiles of spinal cords from Lewis rat models of experimental neuromyelitis optica (ENMO) and experimental autoimmune encephalomyelitis (EAE). We found an upregulation of I-IFN signature genes in EAE spinal cords, and a further upregulation of these genes in ENMO. To learn whether the local I-IFN signature is harmful or beneficial, we induced ENMO by transfer of CNS antigen-specific T cells and NMO-IgG, and treated the animals with I-IFN at the very onset of clinical symptoms, when the blood-brain barrier was open. With this treatment regimen, we could amplify possible effects of the I-IFN induced genes on the transmigration of infiltrating cells through the blood brain barrier, and on lesion formation and expansion, but could avoid effects of I-IFN on the differentiation of pathogenic T and B cells in the lymph nodes. We observed that I-IFN treated ENMO rats had spinal cord lesions with fewer T cells, macrophages/activated microglia and activated neutrophils, and less astrocyte damage than their vehicle treated counterparts, suggesting beneficial effects of I-IFN. PMID:26990978

  11. ROLLER RIG TESTING AT THE CZECH TECHNICAL UNIVERSITY

    Directory of Open Access Journals (Sweden)

    J. Kalivoda

    2016-08-01

    Full Text Available Purpose. Although the advancements in computer simulation technology have paved way to provide very reliable simulation results, track tests still play an essential role during the process of development and homologation of any railway vehicle. On the other hand, track tests depend on weather conditions, are difficult to organize and are not suitable for testing vehicles in critical situations. On a roller rig, the tested vehicle is longitudinally fixed and a track is replaced by rotating rollers. Such device offer testing of railway vehicle running dynamics in safe and stable laboratory environment. The purpose of an article is to investigate and describe roller rig testing at the Czech technical university in Prague (CTU. Methodology. In the paper it is shown the history of development of the scaled CTU roller rig from the earlier stages until the current projects for which the CTU roller rig is utilized for. The current design of the experimental bogie, roller rig, sensors instrumentation and types of experiments conducted at the CTU roller rig are described in more detail. Findings. Although the differences in vehicle behaviour on a track and a scaled model on a roller rig are not negligible, scaled roller rig experiments are found as a relatively inexpensive way for verification and demonstration of computer simulations results. They are especially useful for verification of multibody system simulations (MBS of entirely new running gear concepts. Originality. The CTU roller rig is currently used for the experiments with active controlled wheelset guidance. According to simulations results published in many papers such systems offer, in principle, better performance compared to conventional passive vehicles. However, utilization and testing of active controlled wheelset guidance on vehicles is still rare. CTU roller rig serves as a tool to verify computer simulations and demonstrate benefits of active wheelset guidance. Practical value

  12. Maternal Antibody-Mediated Disease Enhancement in Type I Interferon-Deficient Mice Leads to Lethal Disease Associated with Liver Damage.

    Directory of Open Access Journals (Sweden)

    Julia María Martínez Gómez

    2016-03-01

    Full Text Available Epidemiological studies have reported that most of the severe dengue cases occur upon a secondary heterologous infection. Furthermore, babies born to dengue immune mothers are at greater risk of developing severe disease upon primary infection with a heterologous or homologous dengue virus (DENV serotype when maternal antibodies reach sub-neutralizing concentrations. These observations have been explained by the antibody mediated disease enhancement (ADE phenomenon whereby heterologous antibodies or sub-neutralizing homologous antibodies bind to but fail to neutralize DENV particles, allowing Fc-receptor mediated entry of the virus-antibody complexes into host cells. This eventually results in enhanced viral replication and heightened inflammatory responses. In an attempt to replicate this ADE phenomenon in a mouse model, we previously reported that upon DENV2 infection 5-week old type I and II interferon (IFN receptors-deficient mice (AG129 born to DENV1-immune mothers displayed enhancement of disease severity characterized by increased virus titers and extensive vascular leakage which eventually led to the animals' death. However, as dengue occurs in immune competent individuals, we sought to reproduce this mouse model in a less immunocompromised background. Here, we report an ADE model that is mediated by maternal antibodies in type I IFN receptor-deficient A129 mice. We show that 5-week old A129 mice born to DENV1-immune mothers succumbed to a DENV2 infection within 4 days that was sub-lethal in mice born to naïve mothers. Clinical manifestations included extensive hepatocyte vacuolation, moderate vascular leakage, lymphopenia, and thrombocytopenia. Anti-TNFα therapy totally protected the mice and correlated with healthy hepatocytes. In contrast, blocking IL-6 did not impact the virus titers or disease outcome. This A129 mouse model of ADE may help dissecting the mechanisms involved in dengue pathogenesis and evaluate the efficacy of

  13. Neurotransmitter-Triggered Transfer of Exosomes Mediates Oligodendrocyte–Neuron Communication

    Science.gov (United States)

    Kuo, Wen Ping; Amphornrat, Jesa; Thilemann, Sebastian; Saab, Aiman S.; Kirchhoff, Frank; Möbius, Wiebke; Goebbels, Sandra; Nave, Klaus-Armin; Schneider, Anja; Simons, Mikael; Klugmann, Matthias; Trotter, Jacqueline; Krämer-Albers, Eva-Maria

    2013-01-01

    Reciprocal interactions between neurons and oligodendrocytes are not only crucial for myelination, but also for long-term survival of axons. Degeneration of axons occurs in several human myelin diseases, however the molecular mechanisms of axon-glia communication maintaining axon integrity are poorly understood. Here, we describe the signal-mediated transfer of exosomes from oligodendrocytes to neurons. These endosome-derived vesicles are secreted by oligodendrocytes and carry specific protein and RNA cargo. We show that activity-dependent release of the neurotransmitter glutamate triggers oligodendroglial exosome secretion mediated by Ca2+ entry through oligodendroglial NMDA and AMPA receptors. In turn, neurons internalize the released exosomes by endocytosis. Injection of oligodendroglia-derived exosomes into the mouse brain results in functional retrieval of exosome cargo in neurons. Supply of cultured neurons with oligodendroglial exosomes improves neuronal viability under conditions of cell stress. These findings indicate that oligodendroglial exosomes participate in a novel mode of bidirectional neuron-glia communication contributing to neuronal integrity. PMID:23874151

  14. Neurotransmitter-triggered transfer of exosomes mediates oligodendrocyte-neuron communication.

    Science.gov (United States)

    Frühbeis, Carsten; Fröhlich, Dominik; Kuo, Wen Ping; Amphornrat, Jesa; Thilemann, Sebastian; Saab, Aiman S; Kirchhoff, Frank; Möbius, Wiebke; Goebbels, Sandra; Nave, Klaus-Armin; Schneider, Anja; Simons, Mikael; Klugmann, Matthias; Trotter, Jacqueline; Krämer-Albers, Eva-Maria

    2013-07-01

    Reciprocal interactions between neurons and oligodendrocytes are not only crucial for myelination, but also for long-term survival of axons. Degeneration of axons occurs in several human myelin diseases, however the molecular mechanisms of axon-glia communication maintaining axon integrity are poorly understood. Here, we describe the signal-mediated transfer of exosomes from oligodendrocytes to neurons. These endosome-derived vesicles are secreted by oligodendrocytes and carry specific protein and RNA cargo. We show that activity-dependent release of the neurotransmitter glutamate triggers oligodendroglial exosome secretion mediated by Ca²⁺ entry through oligodendroglial NMDA and AMPA receptors. In turn, neurons internalize the released exosomes by endocytosis. Injection of oligodendroglia-derived exosomes into the mouse brain results in functional retrieval of exosome cargo in neurons. Supply of cultured neurons with oligodendroglial exosomes improves neuronal viability under conditions of cell stress. These findings indicate that oligodendroglial exosomes participate in a novel mode of bidirectional neuron-glia communication contributing to neuronal integrity.

  15. IFN-β: A Contentious Player in Host–Pathogen Interaction in Tuberculosis

    Science.gov (United States)

    Sabir, Naveed; Hussain, Tariq; Shah, Syed Zahid Ali; Zhao, Deming; Zhou, Xiangmei

    2017-01-01

    Tuberculosis (TB) is a major health threat to the human population worldwide. The etiology of the disease is Mycobacterium tuberculosis (Mtb), a highly successful intracellular pathogen. It has the ability to manipulate the host immune response and to make the intracellular environment suitable for its survival. Many studies have addressed the interactions between the bacteria and the host immune cells as involving many immune mediators and other cellular players. Interferon-β (IFN-β) signaling is crucial for inducing the host innate immune response and it is an important determinant in the fate of mycobacterial infection. The role of IFN-β in protection against viral infections is well established and has been studied for decades, but its role in mycobacterial infections remains much more complicated and debatable. The involvement of IFN-β in immune evasion mechanisms adopted by Mtb has been an important area of investigation in recent years. These advances have widened our understanding of the pro-bacterial role of IFN-β in host–pathogen interactions. This pro-bacterial activity of IFN-β appears to be correlated with its anti-inflammatory characteristics, primarily by antagonizing the production and function of interleukin 1β (IL-1β) and interleukin 18 (IL-18) through increased interleukin 10 (IL-10) production and by inhibiting the nucleotide-binding domain and leucine-rich repeat protein-3 (NLRP3) inflammasome. Furthermore, it also fails to provoke a proper T helper 1 (Th1) response and reduces the expression of major histocompatibility complex II (MHC-II) and interferon-γ receptors (IFNGRs). Here we will review some studies to provide a paradigm for the induction, regulation, and role of IFN-β in mycobacterial infection. Indeed, recent studies suggest that IFN-β plays a role in Mtb survival in host cells and its downregulation may be a useful therapeutic strategy to control Mtb infection. PMID:29258190

  16. Dengue Virus Infection Differentially Regulates Endothelial Barrier Function over Time through Type I Interferon Effects

    Science.gov (United States)

    Liu, Ping; Woda, Marcia; Ennis, Francis A.; Libraty, Daniel H.

    2013-01-01

    Background The morbidity and mortality resulting from dengue hemorrhagic fever (DHF) are largely caused by endothelial barrier dysfunction and a unique vascular leakage syndrome. The mechanisms that lead to the location and timing of vascular leakage in DHF are poorly understood. We hypothesized that direct viral effects on endothelial responsiveness to inflammatory and angiogenesis mediators can explain the DHF vascular leakage syndrome. Methods We used an in vitro model of human endothelium to study the combined effects of dengue virus (DENV) type 2 (DENV2) infection and inflammatory mediators on paracellular macromolecule permeability over time. Results Over the initial 72 h after infection, DENV2 suppressed tumor necrosis factor (TNF)–α–mediated hyperpermeability in human umbilical vein endothelial cell (HUVEC) monolayers. This suppressive effect was mediated by type I interferon (IFN). By 1 week, TNF-α stimulation of DENV2-infected HUVECs synergistically increased cell cycling, angiogenic changes, and macromolecule permeability. This late effect could be prevented by the addition of exogenous type I IFN. Conclusions DENV infection of primary human endothelial cells differentially modulates TNF-α–driven angiogenesis and hyperpermeability over time. Type I IFN plays a central role in this process. Our findings suggest a rational model for the DHF vascular leakage syndrome. PMID:19530939

  17. The Winfrith 9MW heat transfer rig

    International Nuclear Information System (INIS)

    Obertelli, J.D.

    1976-01-01

    The Winfrith 9MW Rig is used for studying heat transfer and flow resistance in a variety of test sections at system pressures up to 68 bar. The basic rig and its instrumentation are discussed together with the characteristics of the test section design. The rig has been used in studies involving the full scale simulation of Steam Generating Heavy Water (SGHW) fuel assemblies and the paper discusses the measurements made in this type of study. (author)

  18. Rig supervisors

    International Nuclear Information System (INIS)

    Nordt, D.P.; Stone, M.S.

    1992-01-01

    This paper helps prepare the inexperienced rig supervisor to manage a drilling operation. It outlines operational-knowledge requirements and optimization concepts for improving drilling performance and lowering drilling costs. It gives guidelines on safety and environmental responsibilities, and provides recommendations on work tools, leadership, and communication

  19. Experimental rigs for MHD studies

    International Nuclear Information System (INIS)

    Venkataramani, N.; Jayakumar, R.; Iyer, D.R.; Dixit, N.S.

    1976-01-01

    An MHD experimental rig is a miniature MHD installation consisting of basic equipments necessary for specific investigations. Some of the experimental rigs used in the investigations being carried out at the Bhabha Atomic Research Centre, Bombay (India) are dealt with. The experiments included diagnostics and evaluation of materials in seeded combustion plasmas and argon plasmas. The design specifications, schematics and some of the results of the investigations are also mentioned. (author)

  20. In vivo IFN-γ secretion by NK cells in response to Salmonella typhimurium requires NLRC4 inflammasomes.

    Directory of Open Access Journals (Sweden)

    Andreas Kupz

    Full Text Available Natural killer (NK cells are a critical part of the innate immune defense against viral infections and for the control of tumors. Much less is known about how NK cells contribute to anti-bacterial immunity. NK cell-produced interferon gamma (IFN-γ contributes to the control of early exponential replication of bacterial pathogens, however the regulation of these events remains poorly resolved. Using a mouse model of invasive Salmonellosis, here we report that the activation of the intracellular danger sensor NLRC4 by Salmonella-derived flagellin within CD11c+ cells regulates early IFN-γ secretion by NK cells through the provision of interleukin 18 (IL-18, independently of Toll-like receptor (TLR-signaling. Although IL18-signalling deficient NK cells improved host protection during S. Typhimurium infection, this increased resistance was inferior to that provided by wild-type NK cells. These findings suggest that although NLRC4 inflammasome-driven secretion of IL18 serves as a potent activator of NK cell mediated IFN-γ secretion, IL18-independent NK cell-mediated mechanisms of IFN-γ secretion contribute to in vivo control of Salmonella replication.

  1. Borna disease virus nucleoprotein inhibits type I interferon induction through the interferon regulatory factor 7 pathway

    International Nuclear Information System (INIS)

    Song, Wuqi; Kao, Wenping; Zhai, Aixia; Qian, Jun; Li, Yujun; Zhang, Qingmeng; Zhao, Hong; Hu, Yunlong; Li, Hui; Zhang, Fengmin

    2013-01-01

    Highlights: •IRF7 nuclear localisation was inhibited by BDV persistently infected. •BDV N protein resistant to IFN induction both in BDV infected OL cell and N protein plasmid transfected OL cell. •BDV N protein is related to the inhibition of IRF7 nuclear localisation. -- Abstract: The expression of type I interferon (IFN) is one of the most potent innate defences against viral infection in higher vertebrates. Borna disease virus (BDV) establishes persistent, noncytolytic infections in animals and in cultured cells. Early studies have shown that the BDV phosphoprotein can inhibit the activation of type I IFN through the TBK1–IRF3 pathway. The function of the BDV nucleoprotein in the inhibition of IFN activity is not yet clear. In this study, we demonstrated IRF7 activation and increased IFN-α/β expression in a BDV-persistently infected human oligodendroglia cell line following RNA interference-mediated BDV nucleoprotein silencing. Furthermore, we showed that BDV nucleoprotein prevented the nuclear localisation of IRF7 and inhibited endogenous IFN induction by poly(I:C), coxsackie virus B3 and IFN-β. Our findings provide evidence for a previously undescribed mechanism by which the BDV nucleoprotein inhibits type I IFN expression by interfering with the IRF7 pathway

  2. Type I Interferon-Mediated Skewing of the Serotonin Synthesis Is Associated with Severe Disease in Systemic Lupus Erythematosus

    Science.gov (United States)

    Lood, Christian; Tydén, Helena; Gullstrand, Birgitta; Klint, Cecilia; Wenglén, Christina; Nielsen, Christoffer T.; Heegaard, Niels H. H.; Jönsen, Andreas; Kahn, Robin; Bengtsson, Anders A.

    2015-01-01

    Serotonin, a highly pro-inflammatory molecule released by activated platelets, is formed by tryptophan. Tryptophan is also needed in the production of kynurenine, a process mediated by the type I interferon (IFN)-regulated rate-limiting enzyme indoleamine 2,3-dioxygenase (IDO). The aim of this study was to investigate levels of serotonin in patients with the autoimmune disease systemic lupus erythematosus (SLE), association to clinical phenotype and possible involvement of IDO in regulation of serotonin synthesis. Serotonin levels were measured in serum and plasma from patients with SLE (n=148) and healthy volunteers (n=79) by liquid chromatography and ELISA, as well as intracellularly in platelets by flow cytometry. We found that SLE patients had decreased serotonin levels in serum (p=0.01) and platelets (pserotonin (p=0.0008) as well as increased IDO activity (pserotonin levels in platelets and serum (pserotonin levels were associated with severe SLE with presence of anti-dsDNA antibodies and nephritis. In all, reduced serum serotonin levels in SLE patients were related to severe disease phenotype, including nephritis, suggesting involvement of important immunopathological processes. Further, our data suggest that type I IFNs, present in SLE sera, are able to up-regulate IDO expression, which may lead to decreased serum serotonin levels. PMID:25897671

  3. 29 CFR 1918.54 - Rigging gear.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Rigging gear. 1918.54 Section 1918.54 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Vessel's Cargo Handling Gear § 1918.54 Rigging gear. (a... other alternate device shall be provided to allow trimming of the gear and to prevent employees from...

  4. Ubiquilin 1 Promotes IFN-γ-Induced Xenophagy of Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Erik T Sakowski

    2015-07-01

    Full Text Available The success of Mycobacterium tuberculosis (Mtb as a pathogen rests upon its ability to grow intracellularly in macrophages. Interferon-gamma (IFN-γ is critical in host defense against Mtb and stimulates macrophage clearance of Mtb through an autophagy pathway. Here we show that the host protein ubiquilin 1 (UBQLN1 promotes IFN-γ-mediated autophagic clearance of Mtb. Ubiquilin family members have previously been shown to recognize proteins that aggregate in neurodegenerative disorders. We find that UBQLN1 can interact with Mtb surface proteins and associates with the bacilli in vitro. In IFN-γ activated macrophages, UBQLN1 co-localizes with Mtb and promotes the anti-mycobacterial activity of IFN-γ. The association of UBQLN1 with Mtb depends upon the secreted bacterial protein, EsxA, which is involved in permeabilizing host phagosomes. In autophagy-deficient macrophages, UBQLN1 accumulates around Mtb, consistent with the idea that it marks bacilli that traffic through the autophagy pathway. Moreover, UBQLN1 promotes ubiquitin, p62, and LC3 accumulation around Mtb, acting independently of the E3 ligase parkin. In summary, we propose a model in which UBQLN1 recognizes Mtb and in turn recruits the autophagy machinery thereby promoting intracellular control of Mtb. Thus, polymorphisms in ubiquilins, which are known to influence susceptibility to neurodegenerative illnesses, might also play a role in host defense against Mtb.

  5. Severe fever with thrombocytopenia syndrome virus inhibits exogenous Type I IFN signaling pathway through its NSs invitro.

    Science.gov (United States)

    Chen, Xu; Ye, Haiyan; Li, Shilin; Jiao, Baihai; Wu, Jianqin; Zeng, Peibin; Chen, Limin

    2017-01-01

    Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a novel bunyavirus (SFTS virus, SFTSV). At present there is still no specific antiviral treatment for SFTSV; To understand which cells support SFTSV life cycle and whether SFTSV infection activates host innate immunity, four different cell lines (Vero, Hela, Huh7.5.1, and Huh7.0) were infected with SFTSV. Intracellular/extracellular viral RNA and expression of IFNα, and IFNß were detected by real-time RT- PCR following infection. To confirm the role of non-structural protein (NSs) of SFTSV in exogenous IFNα-induced Jak/STAT signaling, p-STAT1 (Western Blot), ISRE activity (Luciferase assay) and ISG expression (real-time PCR) were examined following IFNα stimulation in the presence or absence of over-expression of NSs in Hela cells. Our study showed that all the four cell lines supported SFTSV life cycle and SFTSV activated host innate immunity to produce type I IFNs in Hela cells but not in Huh7.0, Huh7.5.1 or Vero cells. NSs inhibited exogenous IFNα-induced Jak/STAT signaling as shown by decreased p-STAT1 level, suppressed ISRE activity and down-regulated ISG expression. Suppression of the exogenous Type I IFN-induced Jak/STAT signaling by NSs might be one of the mechanisms of SFTSV to evade host immune surveillance.

  6. Endurance test of DUPIC irradiation test rig-003

    Energy Technology Data Exchange (ETDEWEB)

    Moon, J.S; Yang, M.S.; Lee, C.Y.; Ryu, J.S.; Jeon, H.G

    2001-04-01

    This report presents the pressure drop, vibration and endurance test results for DUPIC Irradiation Test Rig-003 which was design and fabricated by KAERI. From the pressure drop and vibration test results, it is verified that DUPIC Irradiation Test Rig-003 satisfied the limit conditions of HANARO. And, remarkable wear is not observed in DUPIC Irradiation Test Rig-003 during 40 endurance test days.

  7. Field Demonstraton of Existing Microhole Coiled Tubing Rig (MCTR) Technology

    Energy Technology Data Exchange (ETDEWEB)

    Kent Perry; Samih Batarseh; Sheriff Gowelly; Thomas Hayes

    2006-05-09

    The performance of an advanced Microhole Coiled Tubing Rig (MCTR) has been measured in the field during the drilling of 25 test wells in the Niobrara formation of Western Kansas and Eastern Colorado. The coiled tubing (CT) rig designed, built and operated by Advanced Drilling Technologies (ADT), was documented in its performance by GTI staff in the course of drilling wells ranging in depth from 500 to nearly 3,000 feet. Access to well sites in the Niobrara for documenting CT rig performance was provided by Rosewood Resources of Arlington, VA. The ADT CT rig was selected for field performance evaluation because it is one of the most advanced commercial CT rig designs that demonstrate a high degree of process integration and ease of set-up and operation. Employing an information collection protocol, data was collected from the ADT CT rig during 25 drilling events that encompassed a wide range of depths and drilling conditions in the Niobrara. Information collected included time-function data, selected parametric information indicating CT rig operational conditions, staffing levels, and field observations of the CT rig in each phase of operation, from rig up to rig down. The data obtained in this field evaluation indicates that the ADT CT rig exhibited excellent performance in the drilling and completion of more than 25 wells in the Niobrara under varied drilling depths and formation conditions. In the majority of the 25 project well drilling events, ROP values ranged between 300 and 620 feet per hour. For all but the lowest 2 wells, ROP values averaged approximately 400 feet per hour, representing an excellent drilling capability. Most wells of depths between 500 and 2,000 feet were drilled at a total functional rig time of less than 16 hours; for wells as deep at 2,500 to 3,000 feet, the total rig time for the CT unit is usually well under one day. About 40-55 percent of the functional rig time is divided evenly between drilling and casing/cementing. The balance of

  8. Persistent interferon transgene expression by RNA interference-mediated silencing of interferon receptors.

    Science.gov (United States)

    Takahashi, Yuki; Vikman, Elin; Nishikawa, Makiya; Ando, Mitsuru; Watanabe, Yoshihiko; Takakura, Yoshinobu

    2010-09-01

    The in vivo half-life of interferons (IFNs) is very short, and its extension would produce a better therapeutic outcome in IFN-based therapy. Delivery of IFN genes is one solution for providing a sustained supply. IFNs have a variety of functions, including the suppression of transgene expression, through interaction with IFN receptors (IFNRs). This suppression could prevent IFNs from being expressed from vectors delivered. Silencing the expression of IFNAR and IFNGR, the receptors for type I and II IFNs, respectively, in cells expressing IFNs may prolong transgene expression of IFNs. Mouse melanoma B16-BL6 cells or mouse liver were selected as a site expressing IFNs (not a target for IFN gene therapy) and IFN-expressing plasmid DNA was delivered with or without small interfering RNA (siRNA) targeting IFNRs. Transfection of B16-BL6 cells with siRNA targeting IFNAR1 subunit (IFNAR1) resulted in the reduced expression of IFNAR on the cell surface. This silencing significantly increased the IFN-beta production in cells that were transfected with IFN-beta-expressing plasmid DNA. Similar results were obtained with the combination of IFN-gamma and IFNGR. Co-injection of IFN-beta-expressing plasmid DNA with siRNA targeting IFNAR1 into mice resulted in sustained plasma concentration of IFN-beta. These results provide experimental evidence that the RNAi-mediated silencing of IFNRs in cells expressing IFN, such as hepatocytes, is an effective approach for improving transgene expression of IFNs when their therapeutic target comprises cells other than those expressing IFNs.

  9. Type I interferon production during herpes simplex virus infection is controlled by cell-type-specific viral recognition through Toll-like receptor 9, the mitochondrial antiviral signaling protein pathway, and novel recognition systems

    DEFF Research Database (Denmark)

    Rasmussen, Simon Brandtoft; Sørensen, Louise Nørgaard; Malmgaard, Lene

    2007-01-01

    Recognition of viruses by germ line-encoded pattern recognition receptors of the innate immune system is essential for rapid production of type I interferon (IFN) and early antiviral defense. We investigated the mechanisms of viral recognition governing production of type I IFN during herpes...... simplex virus (HSV) infection. We show that early production of IFN in vivo is mediated through Toll-like receptor 9 (TLR9) and plasmacytoid dendritic cells, whereas the subsequent alpha/beta IFN (IFN-alpha/beta) response is derived from several cell types and induced independently of TLR9...

  10. A new generation drilling rig: hydraulically powered and computer controlled

    Energy Technology Data Exchange (ETDEWEB)

    Laurent, M.; Angman, P.; Oveson, D. [Tesco Corp., Calgary, AB, (Canada)

    1999-11-01

    Development, testing and operation of a new generation of hydraulically powered and computer controlled drilling rig that incorporates a number of features that enhance functionality and productivity, is described. The rig features modular construction, a large heated common drilling machinery room, permanently-mounted draw works which, along with the permanently installed top drive, significantly reduces rig-up/rig-down time. Also featured are closed and open hydraulic systems and a unique hydraulic distribution manifold. All functions are controlled through a programmable logic controller (PLC), providing almost unlimited interlocks and calculations to increase rig safety and efficiency. Simplified diagnostic routines, remote monitoring and troubleshooting are also part of the system. To date, two rigs are in operation. Performance of both rigs has been rated as `very good`. Little or no operational problems have been experienced; downtime has averaged 0.61 per cent since August 1998 when the the first of the two rigs went into operation. The most important future application for this rig is for use with the casing drilling process which eliminates the need for drill pipe and tripping. It also reduces the drilling time lost due to unscheduled events such as reaming, fishing and taking kicks while tripping. 1 tab., 6 figs.

  11. Advanced control strategies for a drill rig

    International Nuclear Information System (INIS)

    Banerjee, A.; Hiller, M.; Fink, B.

    1996-01-01

    The construction of tunnels is usually undertaken using a combination of blasting and drilling to achieve rock excavation. Easy handling and high accuracy, and thus greater efficiency, in drilling rigs is an essential ingredient of successful competition in the market place. This article describes a cartesian control concept used for a twin boom drill rig. This simplifies the handling of a drilling boom, reduces the duration of a working cycle and increases security. A remote control system has been added to the drill rig to support the operator working in complicated environments. (UK)

  12. Body Language Advanced 3D Character Rigging

    CERN Document Server

    Allen, Eric; Fong, Jared; Sidwell, Adam G

    2011-01-01

    Whether you're a professional Character TD or just like to create 3D characters, this detailed guide reveals the techniques you need to create sophisticated 3D character rigs that range from basic to breathtaking. Packed with step-by-step instructions and full-color illustrations, Body Language walks you through rigging techniques for all the body parts to help you create realistic and believable movements in every character you design. You'll learn advanced rigging concepts that involve MEL scripting and advanced deformation techniques and even how to set up a character pipeline.

  13. Gulf of Mexico rig activity up, international lags

    International Nuclear Information System (INIS)

    Rappold, K.

    1994-01-01

    Demand for jack up and semisubmersible rigs has improved in the Gulf of Mexico following a decline in activity earlier this year. International drilling activity, however, has shown slight declines in several regions. Relatively firm natural gas prices have helped buoy rig activity in North America. Rig day rates have not followed suit, mainly because of the influx of rigs from weaker international markets. Day rates in the US may not increase until international activity picks up and the world-wide drilling market tightens. Oil prices have hit almost $20/bbl, mainly because of the recent oil worker' strike in Nigeria and good demand. Natural gas prices in the US have hovered around $2.00/MMBTU, and many industry analysts expect gas prices to remain strong over the next few years. This paper gives data on drilling rig counts and crude oil and gas prices in the Gulf of Mexico and onshore

  14. Genome-Derived Cytosolic DNA Mediates Type I Interferon-Dependent Rejection of B Cell Lymphoma Cells

    Directory of Open Access Journals (Sweden)

    Yu J. Shen

    2015-04-01

    Full Text Available The DNA damage response (DDR induces the expression of type I interferons (IFNs, but the underlying mechanisms are poorly understood. Here, we show the presence of cytosolic DNA in different mouse and human tumor cells. Treatment of cells with genotoxic agents increased the levels of cytosolic DNA in a DDR-dependent manner. Cloning of cytosolic DNA molecules from mouse lymphoma cells suggests that cytosolic DNA is derived from unique genomic loci and has the potential to form non-B DNA structures, including R-loops. Overexpression of Rnaseh1, which resolves R-loops, reduced the levels of cytosolic DNA, type I Ifn transcripts, and type I IFN-dependent rejection of lymphoma cells. Live-cell imaging showed a dynamic contact of cytosolic DNA with mitochondria, an important organelle for innate immune recognition of cytosolic nucleotides. In summary, we found that cytosolic DNA is present in many tumor cells and contributes to the immunogenicity of tumor cells.

  15. Enhanced Dendritic Cell-Mediated Antigen-Specific CD4+ T Cell Responses: IFN-Gamma Aids TLR Stimulation

    Directory of Open Access Journals (Sweden)

    Kuo-Ching Sheng

    2013-01-01

    Full Text Available Phenotypic maturation and T cell stimulation are two functional attributes of DCs critical for immune induction. The combination of antigens, including those from cancer, with Toll-like receptor (TLR ligands induces far superior cellular immune responses compared to antigen alone. In this study, IFN-gamma treatment of bone marrow-derived DC, followed by incubation with the TLR2, TLR4, or TLR9 agonists, enhanced DC activation compared to TLR ligation alone. Most notably, the upregulation of CD40 with LPS stimulation and CD86 with CpG stimulation was observed in in vitro cultures. Similarly, IFN-gamma coinjected with TLR ligands was able to promote DC activation in vivo, with DCs migrating from the site of immunization to the popliteal lymph nodes demonstrating increased expression of CD80 and CD86. The heightened DC activation translated to a drastic increase in T cell stimulatory capacity in both antigen independent and antigen dependent fashions. This is the first time that IFN-gamma has been shown to have a combined effect with TLR ligation to enhance DC activation and function. The results demonstrate the novel use of IFN-gamma together with TLR agonists to enhance antigen-specific T cell responses, for applications in the development of enhanced vaccines and drug targets against diseases including cancer.

  16. The ATLAS Muon Trigger Performance in Run I and Initial Run II Performance

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00437899; The ATLAS collaboration

    2016-01-01

    Events with muons in the final state are an important signature for many physics topics at the Large Hadron Collider. An efficient trigger on muons and a detailed understanding of its performance are required. In 2012, the last year of Run I, the instantaneous luminosity reached $7.7\\times10^{33}$ cm$^{-2}$s$^{-1}$ and the average number of interactions that occur in the same bunch crossing was 25. The ATLAS muon trigger has successfully adapted to this challenging environment by making use of isolation requirements, combined trigger signatures with electron and jet trigger objects, and by using so-called full-scan triggers, which make use of the full event information to search for di-lepton signatures, seeded by single lepton objects. A stable and highly efficient muon trigger was vital in the discovery of the Higgs boson in 2012 and for many searches for new physics. The performance of muon triggers during the Large Hadron Collider Run I data-taking campaigns is presented, together with an overview and pre...

  17. Type I interferons as stimulators of DC-mediated cross-priming: impact on anti-tumor response

    Directory of Open Access Journals (Sweden)

    Giovanna eSchiavoni

    2013-12-01

    Full Text Available Induction of potent tumor-specific cytotoxic T-cell responses is a fundamental objective in anticancer therapeutic strategies. This event requires that antigen-presenting cells (APC present tumor-associated antigens (Ag on their MHC class-I molecule, in a process termed cross-presentation. Dendritic cells (DC are particularly keen on this task and can induce the cross-priming of CD8+ T cells, when exposed to danger or inflammatory signals that stimulate their activation. Type I interferons (IFN-I, a family of long-known immunostimulatory cytokines, have been proven to produce optimal activation signal for DC-induced cross-priming. Recent in vitro and in vivo evidences have suggested that IFN-I -stimulated cross-priming by DC against tumor-associated Ag is a key mechanism for cancer immunosurveillance and may be usefully exploited to boost anti-tumor CD8+ T-cell responses. Here, we will review the cross-presentation properties of different DC subsets, with special focus on cell-associated and tumor Ag, and discuss how IFN-I can modify this function, with the aim of identifying more specific and effective strategies for improving anticancer responses.

  18. Type I interferon induction is detrimental during infection with the Whipple's disease bacterium, Tropheryma whipplei.

    Directory of Open Access Journals (Sweden)

    Khatoun Al Moussawi

    2010-01-01

    Full Text Available Macrophages are the first line of defense against pathogens. Upon infection macrophages usually produce high levels of proinflammatory mediators. However, macrophages can undergo an alternate polarization leading to a permissive state. In assessing global macrophage responses to the bacterial agent of Whipple's disease, Tropheryma whipplei, we found that T. whipplei induced M2 macrophage polarization which was compatible with bacterial replication. Surprisingly, this M2 polarization of infected macrophages was associated with apoptosis induction and a functional type I interferon (IFN response, through IRF3 activation and STAT1 phosphorylation. Using macrophages from mice deficient for the type I IFN receptor, we found that this type I IFN response was required for T. whipplei-induced macrophage apoptosis in a JNK-dependent manner and was associated with the intracellular replication of T. whipplei independently of JNK. This study underscores the role of macrophage polarization in host responses and highlights the detrimental role of type I IFN during T. whipplei infection.

  19. Human B cells fail to secrete type I interferons upon cytoplasmic DNA exposure.

    Science.gov (United States)

    Gram, Anna M; Sun, Chenglong; Landman, Sanne L; Oosenbrug, Timo; Koppejan, Hester J; Kwakkenbos, Mark J; Hoeben, Rob C; Paludan, Søren R; Ressing, Maaike E

    2017-11-01

    Most cells are believed to be capable of producing type I interferons (IFN I) as part of an innate immune response against, for instance, viral infections. In macrophages, IFN I is potently induced upon cytoplasmic exposure to foreign nucleic acids. Infection of these cells with herpesviruses leads to triggering of the DNA sensors interferon-inducible protein 16 (IFI16) and cyclic GMP-AMP (cGAMP) synthase (cGAS). Thereby, the stimulator of interferon genes (STING) and the downstream molecules TANK-binding kinase 1 (TBK1) and interferon regulatory factor 3 (IRF3) are sequentially activated culminating in IFN I secretion. Human gamma-herpesviruses, such as Epstein-Barr virus (EBV), exploit B cells as a reservoir for persistent infection. In this study, we investigated whether human B cells, similar to macrophages, engage the cytoplasmic DNA sensing pathway to induce an innate immune response. We found that the B cells fail to secrete IFN I upon cytoplasmic DNA exposure, although they express the DNA sensors cGAS and IFI16 and the signaling components TBK1 and IRF3. In primary human B lymphocytes and EBV-negative B cell lines, this deficiency is explained by a lack of detectable levels of the central adaptor protein STING. In contrast, EBV-transformed B cell lines did express STING, yet both these lines as well as STING-reconstituted EBV-negative B cells did not produce IFN I upon dsDNA or cGAMP stimulation. Our combined data show that the cytoplasmic DNA sensing pathway is dysfunctional in human B cells. This exemplifies that certain cell types cannot induce IFN I in response to cytoplasmic DNA exposure providing a potential niche for viral persistence. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. HIV-1 Promotes the Degradation of Components of the Type 1 IFN JAK/STAT Pathway and Blocks Anti-viral ISG Induction.

    Science.gov (United States)

    Gargan, Siobhan; Ahmed, Suaad; Mahony, Rebecca; Bannan, Ciaran; Napoletano, Silvia; O'Farrelly, Cliona; Borrow, Persephone; Bergin, Colm; Stevenson, Nigel J

    2018-04-01

    Anti-retroviral therapy successfully suppresses HIV-1 infection, but fails to provide a cure. During infection Type 1 IFNs normally play an essential role in viral clearance, but in vivo IFN-α only has a modest impact on HIV-1 infection, suggesting its possible targeting by HIV. Here, we report that the HIV protein, Vif, inhibits effective IFN-α signalling via degradation of essential JAK/STAT pathway components. We found that STAT1 and STAT3 are specifically reduced in HEK293T cells expressing Vif and that full length, infectious HIV-1 IIIB strain promotes their degradation in a Vif-dependent manner. HIV-1 IIIB infection of myeloid ThP-1 cells also reduced the IFN-α-mediated induction of the anti-viral gene, ISG15, but not MxA, revealing a functional consequence of this HIV-1-mediated immune evasion strategy. Interestingly, while total STAT levels were not reduced upon in vitro IIIB infection of primary human PBMCs, IFN-α-mediated phosphorylation of STAT1 and STAT3 and ISG induction were starkly reduced, with removal of Vif (IIIBΔVif), partially restoring pSTATs, ISG15 and MxB induction. Similarly, pSTAT1 and pSTAT3 expression and IFN-α-induced ISG15 were reduced in PBMCs from HIV-infected patients, compared to healthy controls. Furthermore, IFN-α pre-treatment of a CEM T lymphoblast cells significantly inhibited HIV infection/replication (measured by cellular p24), only in the absence of Vif (IIIBΔVif), but was unable to suppress full length IIIB infection. When analysing the mechanism by which Vif might target the JAK/STAT pathway, we found Vif interacts with both STAT1 and STAT3, (but not STAT2), and its expression promotes ubiquitination and MG132-sensitive, proteosomal degradation of both proteins. Vif's Elongin-Cullin-SOCS-box binding motif enables the formation of an active E3 ligase complex, which we found to be required for Vif's degradation of STAT1 and STAT3. In fact, the E3 ligase scaffold proteins, Cul5 and Rbx2, were also found to be

  1. Altered IFN-γ-mediated immunity and transcriptional expression patterns in N-Ethyl-N-nitrosourea-induced STAT4 mutants confer susceptibility to acute typhoid-like disease.

    Science.gov (United States)

    Eva, Megan M; Yuki, Kyoko E; Dauphinee, Shauna M; Schwartzentruber, Jeremy A; Pyzik, Michal; Paquet, Marilène; Lathrop, Mark; Majewski, Jacek; Vidal, Silvia M; Malo, Danielle

    2014-01-01

    Salmonella enterica is a ubiquitous Gram-negative intracellular bacterium that continues to pose a global challenge to human health. The etiology of Salmonella pathogenesis is complex and controlled by pathogen, environmental, and host genetic factors. In fact, patients immunodeficient in genes in the IL-12, IL-23/IFN-γ pathway are predisposed to invasive nontyphoidal Salmonella infection. Using a forward genomics approach by N-ethyl-N-nitrosourea (ENU) germline mutagenesis in mice, we identified the Ity14 (Immunity to Typhimurium locus 14) pedigree exhibiting increased susceptibility following in vivo Salmonella challenge. A DNA-binding domain mutation (p.G418_E445) in Stat4 (Signal Transducer and Activator of Transcription Factor 4) was the causative mutation. STAT4 signals downstream of IL-12 to mediate transcriptional regulation of inflammatory immune responses. In mutant Ity14 mice, the increased splenic and hepatic bacterial load resulted from an intrinsic defect in innate cell function, IFN-γ-mediated immunity, and disorganized granuloma formation. We further show that NK and NKT cells play an important role in mediating control of Salmonella in Stat4(Ity14/Ity14) mice. Stat4(Ity14/Ity14) mice had increased expression of genes involved in cell-cell interactions and communication, as well as increased CD11b expression on a subset of splenic myeloid dendritic cells, resulting in compromised recruitment of inflammatory cells to the spleen during Salmonella infection. Stat4(Ity14/Ity14) presented upregulated compensatory mechanisms, although inefficient and ultimately Stat4(Ity14/Ity14) mice develop fatal bacteremia. The following study further elucidates the pathophysiological impact of STAT4 during Salmonella infection.

  2. Customization creates more efficient, cleaner rigs

    Energy Technology Data Exchange (ETDEWEB)

    Budd, G.

    2002-08-01

    Technological advances in drilling equipment are essential to improving efficiency in the oilpatch; getting the technological upper hand on the competition is no less important for drilling equipment manufacturers than for actors in other sectors of the industry. While off-the-shelf uniformity that reduces unit cost has been the trend in fabricating field gas compression modules, custom manufacturing has become very popular in the rig manufacturing sector. Examples from Crown Energy Technologies and Tesco Corporation, both of Calgary, Aecon Industrial's Edmonton operations, PCL Industrial Construction Ltd of Nisku, and Toromont Process Systems of Houston and Calgary are described to illustrate the widespread demand for customized drilling rigs, including the growing preference for electric drives. Top drive systems, as opposed to rotary drives also have become very popular; six out of ten rigs are sold with electric top drives today compared with fewer than 10 rigs a decade ago. At the same time, Tesco has recently signed a deal with Conoco Inc to construct three revolutionary drilling rigs using Tesco's proprietary Casing Drilling Technology, which uses standard oilfield casing instead of drill pipe, allowing operators to simultaneously drill, case and evaluate oil and gas wells. Aecon and PCL Industrial Construction have had much demand for customized spools and modules particularly from the oil sands industry, while Toromont Process Systems is also expanding its Calgary facilities to meet the demand for its dual gas compression equipment used by power stations for gas compression and co-generation, natural gas refrigeration and specialty gas processing.

  3. JAK inhibitor has the amelioration effect in lupus-prone mice: the involvement of IFN signature gene downregulation.

    Science.gov (United States)

    Ikeda, Keigo; Hayakawa, Kunihiro; Fujishiro, Maki; Kawasaki, Mikiko; Hirai, Takuya; Tsushima, Hiroshi; Miyashita, Tomoko; Suzuki, Satoshi; Morimoto, Shinji; Tamura, Naoto; Takamori, Kenji; Ogawa, Hideoki; Sekigawa, Iwao

    2017-08-22

    We previously reported that JAK-STAT-pathway mediated regulation of IFN-regulatory factor genes could play an important role in SLE pathogenesis. Here, we evaluated the efficacy of the JAK inhibitor tofacitinib (TOFA) for controlling IFN signalling via the JAK-STAT pathway and as a therapeutic for SLE. We treated NZB/NZW F1 mice with TOFA and assessed alterations in their disease, pathological, and immunological conditions. Gene-expression results obtained from CD4 + T cells (SLE mice) and CD3 + T cells (human SLE patients) were measured by DNA microarray and qRT-PCR. TOFA treatment resulted in reduced levels of anti-dsDNA antibodies, decreased proteinuria, and amelioration of nephritis as compared with those observed in control animals. Moreover, we observed the rebalance in the populations of naïve CD4 + T cells and effector/memory cells in TOFA-treated mice; however, treatment with a combination of TOFA and dexamethasone (DEXA) elicited a stronger inhibitory effect toward the effector/memory cells than did TOFA or DEXA monotherapy. We also detected decreased expression of several IFN-signature genes Ifit3 and Isg15 in CD4 + from SLE-prone mice following TOFA and DEXA treatment, and IFIT3 in CD3 + T cells from human patients following immunosuppressant therapy including steroid, respectively. Modulation of type I IFN signalling via JAK-STAT inhibition may exert a beneficial effect in SLE patients, and our results suggest that TOFA could be utilised for the development of new SLE-specific therapeutic strategies.

  4. Deep water challenges for drilling rig design

    Energy Technology Data Exchange (ETDEWEB)

    Roth, M [Transocean Sedco Forex, Houston, TX (United States)

    2001-07-01

    Drilling rigs designed for deep water must meet specific design considerations for harsh environments. The early lessons for rig design came from experiences in the North Sea. Rig efficiency and safety considerations must include structural integrity, isolated/redundant ballast controls, triple redundant DP systems, enclosed heated work spaces, and automated equipment such as bridge cranes, pipe handling gear, offline capabilities, subsea tree handling, and computerized drill floors. All components must be designed to harmonize man and machine. Some challenges which are unique to Eastern Canada include frequent storms and fog, cold temperature, icebergs, rig ice, and difficult logistics. This power point presentation described station keeping and mooring issues in terms of dynamic positioning issues. The environmental influence on riser management during forced disconnects was also described. Design issues for connected deep water risers must insure elastic stability, and control deflected shape. The design must also keep stresses within acceptable limits. Codes and standards for stress limits, flex joints and tension were also presented. tabs., figs.

  5. [Knockdown of STAT3 inhibits proliferation and migration of HepG2 hepatoma cells induced by IFN1].

    Science.gov (United States)

    Li, Xiaofang; Wang, Yuqi; Yan, Ben; Fang, Peipei; Ma, Chao; Xu, Ning; Fu, Xiaoyan; Liang, Shujuan

    2018-02-01

    Objective To prepare lentiviruses expressing shRNA sequences targeting human signal transducer and activator of transcription 3 (STAT3) and detect the effect of STAT3 knockdown on type I interferon (IFN1)-induced proliferation and migration in HepG2 cells. Methods Four STAT3-targeting shRNA sequences (shRNA1-shRNA4) and one control sequence (Ctrl shRNA) were selected and cloned respectively into pLKO.1-sp6-pgk-GFP to construct shRNA-expressing vectors. Along with backbone psPAX2 and pMD2.G vectors, they were separately transfected into HEK293T cells to prepare lentiviruses. HepG2 cells were infected with the lentiviruses. Cytoplastic STAT3 level was detected by Western blotting to screen effective shRNA sequence(s) targeting STAT3. Proliferation and migration of HepG2 cells were analyzed by CCK-8 assay and Transwell TM migration and scratching assay, respectively. To detect the effect of IFN1 on cell proliferation and migration of HepG2 cells, the cells were treated with 2000 U/mL IFNα2b for indicated time and the activation of IFN-triggered STAT1 signal transduction was assayed by Western blotting. Results Two most effective STAT3-targeting shRNA sequences shRNA1 and shRNA2 were selected, and the expression of both STAT3 shRNA significantly decreased proliferation and migration of HepG2 cells. When treated with IFNα2b, 2000 U/mL of IFN1 showed more competent in attenuating growth and migration of HepG2 cells. Our data further proved that knockdown of STAT3 increased the phosphorylation of STAT1, and IFNα2b further enhanced the activation of STAT1 signaling in HepG2 cells. Conclusion Knockdown of STAT3 inhibits cell migration and growth, and rescues IFN response through up-regulating STAT1 signal transduction in HepG2 hepatoma cells.

  6. Phase-I Trigger Readout Electronics Upgrade for the ATLAS Liquid-Argon Calorimeters

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00452211; The ATLAS collaboration

    2017-01-01

    The upgrade of the Large Hadron Collider (LHC) scheduled for the Long Shut-down period of 2019-2020 (LS2), referred to as Phase-I upgrade, will increase the instantaneous luminosity to about three times the design value. Since the current ATLAS trigger system does not allow sucient increase of the trigger rate, an improvement of the trigger system is required. The Liquid Argon (LAr) Calorimeter read-out will therefore be modi ed to use digital trigger signals with a higher spatial granularity in order to improve the identi cation effciencies of electrons, photons, tau, jets and missing energy, at high background rejection rates at the Level-1 trigger.

  7. IFN-ε is constitutively expressed by cells of the reproductive tract and is inefficiently secreted by fibroblasts and cell lines.

    Directory of Open Access Journals (Sweden)

    Pascale Hermant

    Full Text Available Type-I interferons (IFNs form a large family of cytokines that primarily act to control the early development of viral infections. Typical type-I IFN genes, such as those encoding IFN-α or IFN-β are upregulated by viral infection in many cell types. In contrast, the gene encoding IFN-ε was reported to be constitutively expressed by cells of the female reproductive tract and to contribute to the protection against vaginal infections with herpes simplex virus 2 and Chlamydia muridarum. Our data confirm the lack of induction of IFN-ε expression after viral infection and the constitutive expression of IFN-ε by cells of the female but also of the male reproductive organs. Interestingly, when expressed from transfected expression plasmids in 293T, HeLa or Neuro2A cells, the mouse and human IFN-ε precursors were inefficiently processed and secretion of IFN-ε was minimal. Analysis of chimeric constructs produced between IFN-ε and limitin (IFN-ζ showed that both the signal peptide and the mature moiety of IFN-ε contribute to poor processing of the precursor. Immunofluorescent detection of FLAG-tagged IFN-ε in transfected cells suggested that IFN-ε and chimeric proteins were defective for progression through the secretory pathway. IFN-ε did not, however, act intracellularly and impart an antiviral state to producing cells. Given the constitutive expression of IFN-ε in specialized cells and the poor processing of IFN-ε precursor in fibroblasts and cell lines, we hypothesize that IFN-ε secretion may require a co-factor specifically expressed in cells of the reproductive organs, that might secure the system against aberrant release of this IFN.

  8. Innovative technology for a cost-effective land rig

    Energy Technology Data Exchange (ETDEWEB)

    Mehra, S.; Bryce, T.

    1996-05-01

    Sedco Forex has recently completed a new land drilling rig, currently deployed in Gabon, that integrates well construction activities with multiskilling to create cost savings across the board in drilling operations. Historically, operators have produced a comprehensive tender package specifying strictly the type and size of individual rig components and the number of personnel required to drill. In this case, the drilling contractor provides a fit-for-purpose rig, consistent with field location, well profile, operator`s priorities, and local constraints.

  9. Innovative technology for a cost-effective land rig

    International Nuclear Information System (INIS)

    Mehra, S.; Bryce, T.

    1996-01-01

    Sedco Forex has recently completed a new land drilling rig, currently deployed in Gabon, that integrates well construction activities with multiskilling to create cost savings across the board in drilling operations. Historically, operators have produced a comprehensive tender package specifying strictly the type and size of individual rig components and the number of personnel required to drill. In this case, the drilling contractor provides a fit-for-purpose rig, consistent with field location, well profile, operator's priorities, and local constraints

  10. Reversible silencing of cytomegalovirus genomes by type I interferon governs virus latency.

    Directory of Open Access Journals (Sweden)

    Franziska Dağ

    2014-02-01

    Full Text Available Herpesviruses establish a lifelong latent infection posing the risk for virus reactivation and disease. In cytomegalovirus infection, expression of the major immediate early (IE genes is a critical checkpoint, driving the lytic replication cycle upon primary infection or reactivation from latency. While it is known that type I interferon (IFN limits lytic CMV replication, its role in latency and reactivation has not been explored. In the model of mouse CMV infection, we show here that IFNβ blocks mouse CMV replication at the level of IE transcription in IFN-responding endothelial cells and fibroblasts. The IFN-mediated inhibition of IE genes was entirely reversible, arguing that the IFN-effect may be consistent with viral latency. Importantly, the response to IFNβ is stochastic, and MCMV IE transcription and replication were repressed only in IFN-responsive cells, while the IFN-unresponsive cells remained permissive for lytic MCMV infection. IFN blocked the viral lytic replication cycle by upregulating the nuclear domain 10 (ND10 components, PML, Sp100 and Daxx, and their knockdown by shRNA rescued viral replication in the presence of IFNβ. Finally, IFNβ prevented MCMV reactivation from endothelial cells derived from latently infected mice, validating our results in a biologically relevant setting. Therefore, our data do not only define for the first time the molecular mechanism of IFN-mediated control of CMV infection, but also indicate that the reversible inhibition of the virus lytic cycle by IFNβ is consistent with the establishment of CMV latency.

  11. Computer gaming comes to service rig training

    Energy Technology Data Exchange (ETDEWEB)

    Mowers, J.

    2007-05-15

    This article addressed the challenge of providing service rig workers with a good understanding of the tasks and risks involved in the job before they even step out into the field. The product, SimuLynx was presented. SimuLynx is based on video and gaming technology to immerse the user in the service rig work environment with other crew members. The user tries to perform the different steps of a junior floorhand's job while a coach gives directions. The article discussed how the system works. For example, when faced with a task, the user chooses from several options. The coach informs the virtual junior floorhand if the decision was right or wrong. He will also give warnings and let the user realize the consequences of a wrong action. The benefits of the system were also presented. For example, instead of 30 days of on-the-job training, an employee may only need several days after going through the program. Other benefits that were reviewed included reduced accident risk-levels for new workers; higher rig efficiency; and, lower training costs. In addition, a potential recruit can decide if the job is right for him before signing up for an expensive course or starting off with a service rig company. As well, the rig company can decide if someone is suitable before hiring that person. 3 figs.

  12. Mullerian Inhibiting Substances (MIS) Augments IFN-gamma Mediated Inhibition of Breast Cancer Cell Growth

    National Research Council Canada - National Science Library

    Gupta, Vandana

    2006-01-01

    MIS is a member of the TGF family. The purpose of this study is to test the hypothesis that MIS and IFN-gamma might be more effective in the inhibition of breast cancer cell growth than either agent alone...

  13. Impaired chromatin remodelling at STAT1-regulated promoters leads to global unresponsiveness of Toxoplasma gondii-infected macrophages to IFN-γ.

    Directory of Open Access Journals (Sweden)

    Christine Lang

    2012-01-01

    Full Text Available Intracellular pathogens including the apicomplexan and opportunistic parasite Toxoplasma gondii profoundly modify their host cells in order to establish infection. We have shown previously that intracellular T. gondii inhibit up-regulation of regulatory and effector functions in murine macrophages (MΦ stimulated with interferon (IFN-γ, which is the cytokine crucial for controlling the parasites' replication. Using genome-wide transcriptome analysis we show herein that infection with T. gondii leads to global unresponsiveness of murine macrophages to IFN-γ. More than 61% and 89% of the transcripts, which were induced or repressed by IFN-γ in non-infected MΦ, respectively, were not altered after stimulation of T. gondii-infected cells with IFN-γ. These genes are involved in a variety of biological processes, which are mostly but not exclusively related to immune responses. Analyses of the underlying mechanisms revealed that IFN-γ-triggered nuclear translocation of STAT1 still occurred in Toxoplasma-infected MΦ. However, STAT1 bound aberrantly to oligonucleotides containing the IFN-γ-responsive gamma-activated site (GAS consensus sequence. Conversely, IFN-γ did not induce formation of active GAS-STAT1 complexes in nuclear extracts from infected MΦ. Mass spectrometry of protein complexes bound to GAS oligonucleotides showed that T. gondii-infected MΦ are unable to recruit non-muscle actin to IFN-γ-responsive DNA sequences, which appeared to be independent of stimulation with IFN-γ and of STAT1 binding. IFN-γ-induced recruitment of BRG-1 and acetylation of core histones at the IFN-γ-regulated CIITA promoter IV, but not β-actin was diminished by >90% in Toxoplasma-infected MΦ as compared to non-infected control cells. Remarkably, treatment with histone deacetylase inhibitors restored the ability of infected macrophages to express the IFN-γ regulated genes H2-A/E and CIITA. Taken together, these results indicate that Toxoplasma

  14. Exogenous IFN-beta regulates the RANKL-c-Fos-IFN-beta signaling pathway in the collagen antibody-induced arthritis model.

    Science.gov (United States)

    Zhao, Rong; Chen, Ni-Nan; Zhou, Xiao-Wei; Miao, Ping; Hu, Chao-Ying; Qian, Liu; Yu, Qi-Wen; Zhang, Ji-Ying; Nie, Hong; Chen, Xue-hua; Li, Pu; Xu, Rong; Xiao, Lian-Bo; Zhang, Xin; Liu, Jian-Ren; Zhang, Dong-Qing

    2014-12-10

    Although a variety of drugs have been used to treat the symptoms of rheumatoid arthritis (RA), none of them are able to cure the disease. Interferon β (IFN-β) has pleiotropic effects on RA, but whether it can be used to treat RA remains globally controversial. Thus, in this study we tested the effects of IFN-β on RA patients and on collagen antibody-induced arthritis (CAIA) model mice. The cytokine and auto-antibody expression profiles in the serum and synovial fluid (SF) from RA patients were assessed using enzyme-linked immunosorbent assay (ELISA) and compared with the results from osteoarthritis (OA) patients. Exogenous IFN-β was administered to RA patients and CAIA model mice, and the therapeutic effects were evaluated. Endogenous IFN-β expression in the joint bones of CAIA model mice was evaluated by quantitative real-time PCR (qRT-PCR). The effects of exogenous IFN-β on CAIA model mice were assessed using a clinical scoring system, hematoxylin eosin and safranin-O with fast green counterstain histology, molybdenum target X-ray, and tartrate-resistant acid phosphatase (TRAP) staining. The RANKL-RANK signaling pathway was analyzed using qRT-PCR. The RAW 264.7 cell line was differentiated into osteoclasts with RANKL stimulation and then treated with exogenous IFN-β. The expression of inflammatory cytokines (IFN-γ, IL-17, MMP-3, and RANKL) and auto-antibodies (CII antibodies, RF-IgM, and anti-CCP/GPI) were significantly higher in RA compared with OA patients. After IFN-β intervention, some clinical symptoms in RA patients were partially alleviated, and the expression of IFN-γ, IL-17, MMP-3, and OPG) returned to normal levels. In the CAIA model, the expression of endogenous IFN-β in the joint bones was decreased. After IFN-β administration, the arthritis scores were decreased; synovial inflammation, cartilage, and bone destruction were clearly attenuated; and the expression of c-Fos and NFATc1 were reduced, while RANKL and TRAF6 expression was

  15. Preassembly and ligand-induced restructuring of the chains of the IFN-gamma receptor complex: the roles of Jak kinases, Stat1 and the receptor chains.

    Science.gov (United States)

    Krause, Christopher D; Lavnikova, Natasha; Xie, Junxia; Mei, Erwen; Mirochnitchenko, Olga V; Jia, Yiwei; Hochstrasser, Robin M; Pestka, Sidney

    2006-01-01

    We previously demonstrated using noninvasive technologies that the interferon-gamma (IFN-gamma) receptor complex is preassembled (1). In this report we determined how the receptor complex is preassembled and how the ligand-mediated conformational changes occur. The interaction of Stat1 with IFN-gammaR1 results in a conformational change localized to IFN-gammaR1. Jak1 but not Jak2 is required for the two chains of the IFN-gamma receptor complex (IFN-gammaR1 and IFN-gammaR2) to interact; however, the presence of both Jak1 and Jak2 is required to see any ligand-dependant conformational change. Two IFN-gammaR2 chains interact through species-specific determinants in their extracellular domains. Finally, these determinants also participate in the interaction of IFN-gammaR2 with IFN-gammaR1. These results agree with a detailed model of the IFN-gamma receptor that requires the receptor chains to be pre-associated constitutively for the receptor to be active.

  16. CD4(+) T cell-mediated protection against a lethal outcome of systemic infection with vesicular stomatitis virus requires CD40 ligand expression, but not IFN-gamma or IL-4

    DEFF Research Database (Denmark)

    Andersen, C; Jensen, T; Nansen, A

    1999-01-01

    experiments using B cell- and T cell-deficient recipients revealed that no protection could be obtained in the absence of B cells, whereas treatment with virus-specific immune (IgG) serum controlled viral spreading to the central nervous system (CNS), but did not necessarily accomplish virus elimination......To investigate the mechanism(s) whereby T cells protect against a lethal outcome of systemic infection with vesicular stomatitis virus, mice with targeted defects in genes central to T cell function were tested for resistance to i.v. infection with this virus. Our results show that mice lacking...... the capacity to secrete both IFN-gamma and perforin completely resisted disease. Similar results were obtained using IL-4 knockout mice, indicating that neither cell-mediated nor T(h)2-dependent effector systems were required. In contrast, mice deficient in expression of CD40 ligand were more susceptible than...

  17. Type III Interferon-Mediated Signaling Is Critical for Controlling Live Attenuated Yellow Fever Virus Infection In Vivo.

    Science.gov (United States)

    Douam, Florian; Soto Albrecht, Yentli E; Hrebikova, Gabriela; Sadimin, Evita; Davidson, Christian; Kotenko, Sergei V; Ploss, Alexander

    2017-08-15

    Yellow fever virus (YFV) is an arthropod-borne flavivirus, infecting ~200,000 people worldwide annually and causing about 30,000 deaths. The live attenuated vaccine strain, YFV-17D, has significantly contributed in controlling the global burden of yellow fever worldwide. However, the viral and host contributions to YFV-17D attenuation remain elusive. Type I interferon (IFN-α/β) signaling and type II interferon (IFN-γ) signaling have been shown to be mutually supportive in controlling YFV-17D infection despite distinct mechanisms of action in viral infection. However, it remains unclear how type III IFN (IFN-λ) integrates into this antiviral system. Here, we report that while wild-type (WT) and IFN-λ receptor knockout (λR -/- ) mice were largely resistant to YFV-17D, deficiency in type I IFN signaling resulted in robust infection. Although IFN-α/β receptor knockout (α/βR -/- ) mice survived the infection, mice with combined deficiencies in both type I signaling and type III IFN signaling were hypersusceptible to YFV-17D and succumbed to the infection. Mortality was associated with viral neuroinvasion and increased permeability of the blood-brain barrier (BBB). α/βR -/- λR -/- mice also exhibited distinct changes in the frequencies of multiple immune cell lineages, impaired T-cell activation, and severe perturbation of the proinflammatory cytokine balance. Taken together, our data highlight that type III IFN has critical immunomodulatory and neuroprotective functions that prevent viral neuroinvasion during active YFV-17D replication. Type III IFN thus likely represents a safeguard mechanism crucial for controlling YFV-17D infection and contributing to shaping vaccine immunogenicity. IMPORTANCE YFV-17D is a live attenuated flavivirus vaccine strain recognized as one of the most effective vaccines ever developed. However, the host and viral determinants governing YFV-17D attenuation and its potent immunogenicity are still unknown. Here, we analyzed the

  18. Phase-I Trigger Readout Electronics Upgrade for the ATLAS Liquid-Argon Calorimeters

    CERN Document Server

    Camplani, Alessandra; The ATLAS collaboration

    2017-01-01

    The upgrade of the Large Hadron Collider (LHC) scheduled for shut-down period of 2018-2019, referred to as Phase-I upgrade, will increase the instantaneous luminosity to about three times the design value. Since the current ATLAS trigger system does not allow sufficient increase of the trigger rate, an improvement of the trigger system is required. The Liquid Argon (LAr) Calorimeter read-out will therefore be modified to use digital trigger signals with a higher spatial granularity in order to improve the identification efficiencies of electrons, photons, tau, jets and missing energy, at high background rejection rates at the Level-1 trigger. The new trigger signals will be arranged in 34000 so-called Super Cells which achieves 5-10 times better granularity than the trigger towers currently used and allows an improved background rejection. The readout of the trigger signals will process the signal of the Super Cells at every LHC bunch-crossing at 12-bit precision and a frequency of 40 MHz. The data will be tr...

  19. Phase - I Trigger Readout Electronics upgrade for the ATLAS Liquid Argon Calorimeters

    CERN Document Server

    Dinkespiler, Bernard; The ATLAS collaboration

    2017-01-01

    The upgrade of the Large Hadron Collider (LHC) scheduled for shut-down period of 2018-2019, referred to as Phase-I upgrade, will increase the instantaneous luminosity to about three times the design value. Since the current ATLAS trigger system does not allow sufficient increase of the trigger rate, an improvement of the trigger system is required. The Liquid Argon (LAr) Calorimeter read-out will therefore be modified to use digital trigger signals with a higher spatial granularity in order to improve the identification efficiencies of electrons, photons, tau, jets and missing energy, at high background rejection rates at the Level-1 trigger. The new trigger signals will be arranged in 34000 so-called Super Cells which achieves 5-10 times better granularity than the trigger towers currently used and allows an improved background rejection. The readout of the trigger signals will process the signal of the Super Cells at every LHC bunch-crossing at 12-bit precision and a frequency of 40 MHz. The data will be tr...

  20. Thymoquinone Suppresses IRF-3-Mediated Expression of Type I Interferons via Suppression of TBK1

    Directory of Open Access Journals (Sweden)

    Nur Aziz

    2018-05-01

    Full Text Available Interferon regulatory factor (IRF-3 is known to have a critical role in viral and bacterial innate immune responses by regulating the production of type I interferon (IFN. Thymoquinone (TQ is a compound derived from black cumin (Nigella sativa L. and is known to regulate immune responses by affecting transcription factors associated with inflammation, including nuclear factor-κB (NF-κB and activator protein-1 (AP-1. However, the role of TQ in the IRF-3 signaling pathway has not been elucidated. In this study, we explored the molecular mechanism of TQ-dependent regulation of enzymes in IRF-3 signaling pathways using the lipopolysaccharide (LPS-stimulated murine macrophage-like RAW264.7 cell line. TQ decreased mRNA expression of the interferon genes IFN-α and IFN-β in these cells. This inhibition was due to its suppression of the transcriptional activation of IRF-3, as shown by inhibition of IRF-3 PRD (III-I luciferase activity as well as the phosphorylation pattern of IRF-3 in the immunoblotting experiment. Moreover, TQ targeted the autophosphorylation of TANK-binding kinase 1 (TBK1, an upstream key enzyme responsible for IRF-3 activation. Taken together, these findings suggest that TQ can downregulate IRF-3 activation via inhibition of TBK1, which would subsequently decrease the production of type I IFN. TQ also regulated IRF-3, one of the inflammatory transcription factors, providing a novel insight into its anti-inflammatory activities.

  1. Analysis of IL-12 p40 subunit gene and IFN-γ G5644A polymorphisms in Idiopathic Pulmonary Fibrosis

    Directory of Open Access Journals (Sweden)

    Welsh Kenneth I

    2003-06-01

    Full Text Available Abstract Background Genes encoding cytokine mediators are prime candidates for genetic analysis in conditions with T-helper (Th cell disease driven imbalance. Idiopathic Pulmonary Fibrosis (IPF is a predominantly Th2 mediated disease associated with a paucity of interferon-gamma (IFN-γ. The paucity of IFN-γ may favor the development of progressive fibrosis in IPF. Interleukin-12 (IL-12 plays a key role in inducing IFN-γ production. The aim of the current study was to assess whether the 1188 (A/C 3'UTR single nucleotide polymorphism (SNP in the IL-12 p40 subunit gene which was recently found to be functional and the 5644 (G/A 3' UTR SNP of the IFN-γ gene were associated with susceptibility to IPF. Methods We investigated the allelic distribution in these loci in UK white Caucasoid subjects comprising 73 patients with IPF and 157 healthy controls. The SNPs were determined using the polymerase chain reaction in association with sequence-specific primers incorporating mismatches at the 3'-end. Results Our results showed that these polymorphisms were distributed similarly in the IPF and control groups Conclusion We conclude that these two potentially important candidate gene single nucleotide polymorphisms are not associated with susceptibility to IPF.

  2. Type I Interferons Direct Gammaherpesvirus Host Colonization.

    Directory of Open Access Journals (Sweden)

    Cindy S E Tan

    2016-05-01

    Full Text Available Gamma-herpesviruses colonise lymphocytes. Murid Herpesvirus-4 (MuHV-4 infects B cells via epithelial to myeloid to lymphoid transfer. This indirect route entails exposure to host defences, and type I interferons (IFN-I limit infection while viral evasion promotes it. To understand how IFN-I and its evasion both control infection outcomes, we used Mx1-cre mice to tag floxed viral genomes in IFN-I responding cells. Epithelial-derived MuHV-4 showed low IFN-I exposure, and neither disrupting viral evasion nor blocking IFN-I signalling markedly affected acute viral replication in the lungs. Maximising IFN-I induction with poly(I:C increased virus tagging in lung macrophages, but the tagged virus spread poorly. Lymphoid-derived MuHV-4 showed contrastingly high IFN-I exposure. This occurred mainly in B cells. IFN-I induction increased tagging without reducing viral loads; disrupting viral evasion caused marked attenuation; and blocking IFN-I signalling opened up new lytic spread between macrophages. Thus, the impact of IFN-I on viral replication was strongly cell type-dependent: epithelial infection induced little response; IFN-I largely suppressed macrophage infection; and viral evasion allowed passage through B cells despite IFN-I responses. As a result, IFN-I and its evasion promoted a switch in infection from acutely lytic in myeloid cells to chronically latent in B cells. Murine cytomegalovirus also showed a capacity to pass through IFN-I-responding cells, arguing that this is a core feature of herpesvirus host colonization.

  3. CA1 Pyramidal Cell Theta-Burst Firing Triggers Endocannabinoid-Mediated Long-Term Depression at Both Somatic and Dendritic Inhibitory Synapses

    Science.gov (United States)

    Younts, Thomas J.; Chevaleyre, Vivien

    2013-01-01

    Endocannabinoids (eCBs) are retrograde lipid messengers that, by targeting presynaptic type 1 cannabinoid receptors (CB1Rs), mediate short- and long-term synaptic depression of neurotransmitter release throughout the brain. Short-term depression is typically triggered by postsynaptic, depolarization-induced calcium rises, whereas long-term depression is induced by synaptic activation of Gq/11 protein-coupled receptors. Here we report that a physiologically relevant pattern of postsynaptic activity, in the form of theta-burst firing (TBF) of hippocampal CA1 pyramidal neurons, can trigger long-term depression of inhibitory transmission (iLTD) in rat hippocampal slices. Paired recordings between CA1 interneurons and pyramidal cells, followed by post hoc morphological reconstructions of the interneurons' axon, revealed that somatic and dendritic inhibitory synaptic inputs equally expressed TBF-induced iLTD. Simultaneous recordings from neighboring pyramidal cells demonstrated that eCB signaling triggered by TBF was highly restricted to only a single, active cell. Furthermore, pairing submaximal endogenous activation of metabotropic glutamate or muscarinic acetylcholine receptors with submaximal TBF unmasked associative iLTD. Although CB1Rs are also expressed at Schaffer-collateral excitatory terminals, long-term plasticity under various recording conditions was spared at these synapses. Consistent with this observation, TBF also shifted the balance of excitation and inhibition in favor of excitatory throughput, thereby altering information flow through the CA1 circuit. Given the near ubiquity of burst-firing activity patterns and CB1R expression in the brain, the properties described here may be a general means by which neurons fine tune the strength of their inputs in a cell-wide and cell-specific manner. PMID:23966696

  4. Suppression of the toll-like receptor 7-dependent type I interferon production pathway by autophagy resulting from enterovirus 71 and coxsackievirus A16 infections facilitates their replication.

    Science.gov (United States)

    Song, Jie; Hu, Yajie; Li, Jiaqi; Zheng, Huiwen; Wang, Jingjing; Guo, Lei; Shi, Haijng; Liu, Longding

    2018-01-01

    Toll-like receptors (TLRs) act as molecular sentinels, detecting invading viral pathogens and triggering host innate immune responses, including autophagy. However, many viruses have evolved a series of strategies to manipulate autophagy for their own benefit. Enterovirus 71 (EV71) and coxsackievirus A16 (CA16), as the primary agents causing hand, foot and mouth disease (HFMD), can induce autophagy leading to their replication. Therefore, the objective of this study was to investigate whether enhanced viral replication caused by autophagy in EV71 and CA16 infections was associated with a TLR-related signaling pathway. Our results demonstrate that complete autophagy and incomplete autophagy were observed in human bronchial epithelial (16HBE) cells infected with EV71 and CA16. Moreover, suppression of autophagy by the pharmacological modulator 3-MA significantly and clearly decreased the survival rates and viral replication of EV71 and CA16 in 16HBE cells. Inhibition of autophagy also enhanced the expression of molecules related to the TLR7-dependent type I interferon (IFN-I) production pathway, such as TLR7, MyD88, IRF7 and IFN-α/β. Finally, immunofluorescence staining demonstrated that TLR7 endosome marker M6PR levels were clearly reduced in EV71- and CA16-infected cells, while they were markedly elevated in infected cells treated with 3-MA. These findings suggest that increased EV71 and CA16 replication meditated by autophagy in 16HBE cells might promote degradation of the endosome, leading to suppression of the TLR7-mediated IFN-I signaling pathway.

  5. Role of IFN-gamma and LPS on Neuron/Glial Co-Cultures Infected by Neospora caninum

    Directory of Open Access Journals (Sweden)

    Erica Etelvina Viana De Jesus

    2014-10-01

    Full Text Available Neospora caninum causes cattle abortion and neurological symptoms in dogs. Although infection is usually asymptomatic, classical neurological symptoms of neosporosis may be associated with encephalitis. This parasite can grow in brain endothelial cells without markedly damages, but it can modulate the cellular environment to promote its survival in the brain. In previous studies, we described that IFN-γ decreased the parasite proliferation and down regulated nitric oxide production in astrocyte/microglia cultures. However, it remains unclear how glial cells respond to N. caninum in the presence of neurons. Therefore, we evaluated the effect of 300 IU/mL IFN-γ or 1.0 μg/mL of LPS on infected rat neuron/glial co-cultures. After 72 hours of infection, LPS did not affect the mitochondrial dehydrogenase activity. However, IFN-γ decreased this parameter by 15.5 and 12.0% in uninfected and infected cells, respectively. The number of tachyzoites decreased 54.1 and 44.3% in cells stimulated with IFN-γ and LPS, respectively. Infection or LPS treatment did not change NO production. On the other hand, IFN-γ induced increased nitrite release in 55.7%, but the infection reverted this induction. IL-10 levels increased only in infected cultures (treated or not, meanwhile PGE2 release was improved in IFN-γ/infected or LPS/infected cells. Although IFN-γ significantly reduced the neurite length in uninfected cultures (42.64%; p < 0.001, this inflammatory cytokine reverted the impairment of neurite outgrowth induced by the infection (81.39%. The results suggest a neuroprotective potential response of glia to N. caninum infection under IFN-γ stimulus. This observation contributes to understand the immune mediated mechanisms of neosporosis in CNS

  6. The role of the rigged Hilbert space in quantum mechanics

    International Nuclear Information System (INIS)

    Madrid, Rafael de la

    2005-01-01

    There is compelling evidence that, when a continuous spectrum is present, the natural mathematical setting for quantum mechanics is the rigged Hilbert space rather than just the Hilbert space. In particular, Dirac's braket formalism is fully implemented by the rigged Hilbert space rather than just by the Hilbert space. In this paper, we provide a pedestrian introduction to the role the rigged Hilbert space plays in quantum mechanics, by way of a simple, exactly solvable example. The procedure will be constructive and based on a recent publication. We also provide a thorough discussion on the physical significance of the rigged Hilbert space

  7. IFN-alpha antibodies in patients with age-related macular degeneration treated with recombinant human IFN-alpha2a

    DEFF Research Database (Denmark)

    Ross, Christian; Engler, Claus Bødker; Sander, Birgit

    2002-01-01

    We tested for development of binding and neutralizing antibodies to interferon-alpha (IFN-alpha) during IFN-alpha2a therapy of patients with age-related macular degeneration (AMD) of the eyes. Antibodies were investigated retrospectively in sera of 34 patients treated with 3 x 10(6) IU IFN-alpha2...

  8. IFN-alpha antibodies in patients with age-related macular degeneration treated with recombinant human IFN-alpha2a

    DEFF Research Database (Denmark)

    Ross, Christian; Engler, Claus Bødker; Sander, Birgit

    2002-01-01

    We tested for development of binding and neutralizing antibodies to interferon-alpha (IFN-alpha) during IFN-alpha2a therapy of patients with age-related macular degeneration (AMD) of the eyes. Antibodies were investigated retrospectively in sera of 34 patients treated with 3 x 10(6) IU IFN-alpha2a...

  9. 21. century drilling rigs -- Tesco introduces new modular design

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-10-01

    Development of a modular, hydraulic, self-elevating drilling rig, dubbed the `21. century drilling rig` was announced by the Tesco Corporation. The rig equipment is housed in 8 by 20 by 8.5 feet high sea containers that can be handled by a 20-ton oilfield picker. These containers, weighing about 15,000 to 20,000 pounds on average, eliminate the need for heavy and bulky standard oilfield skid buildings, besides avoiding costly over-width and over-weight permits. The containers can be easily shipped around the world at a fraction of the cost of shipping standard oilfield skid buildings. Time for shipping on land is comparable to conventional rigs, but with the added advantage of smaller and lighter loads, promising fewer transportation problems during spring breakup. Tesco also designed and built an 85-foot long, triple-axle, 24-wheel catwalk trailer to transport the top drive, drawworks and double telescoping mast as one unit. Another novel characteristic of this unit is that the hydraulic system is capable of selectable distribution of power to the main functions such as the top drive, drawworks, or mud pump, similar to the electric SCR rig. The rig also features a computerized control system managed by programmable logic controllers. The split crown and split block to facilitate wireline work, are other innovative features worthy of note.

  10. Statistikeren skiftede spor som 49-årig

    DEFF Research Database (Denmark)

    Sølund, Sune; Rootzén, Helle

    2010-01-01

    En uddannelse til coach har ændret Helle Rototzens liv. Som 49-årig forlod hun et forskerliv på deltid til fordel for en karriere som DTU's eneste kvindelige institutdirektør.......En uddannelse til coach har ændret Helle Rototzens liv. Som 49-årig forlod hun et forskerliv på deltid til fordel for en karriere som DTU's eneste kvindelige institutdirektør....

  11. Minimal disturbance : Ensign's ADR-1000-CT rig aimed at CBM market

    International Nuclear Information System (INIS)

    Roche, P.

    2005-01-01

    Ensign Resource Services Group Inc. has recently designed a light, mobile rig aimed at Western Canada's coalbed methane (CBM) market. With a 1000 metre depth rating, the automated ADR-1000-CT rig can drill with either jointed pipe or 3 and a half-inch coil. Tractor units are used to move the rig to avoid the extra traffic generated by third-party trucks. The rig's self-levelling capability creates less environmental disturbance. Each component works on sites with as much as 2 metres difference in elevation, which reduces the need for earth-moving equipment. As drilling moves closer to farms and acreages, minimal environmental disturbance is crucial to the CBM industry. The rig won a 2005 Alberta government award for innovations in workplace health and safety as the design eliminates many of the tasks where injuries occur on conventional rigs. On conventional rigs, drill-strings are suspended from a travelling block which is suspended from the crown of a large, heavy derrick. With the ADR, hydraulic cylinders bear the weight of the drill string, and the derrick serves mainly to guide the top drive. When drilling only with jointed pipe, the coiled-tubing reel is a separate load so that drilling crews don't have to transport it around on programs requiring only jointed pipe. If coil is needed, the reel can be trucked to the site and plugged in to the rest of the rig. Tubing is expected to last 3 times as long as on a regular coiled-tubing rig, as the reel is positioned directly over the rotary table. The rigs have been used for various drilling projects and have performed satisfactorily with high penetration rates due to their large mud pumps. It was concluded that the ADR-1000-CT rig's hydraulic self-levelling capability and agility are helpful features when drilling in a minimal disturbance environment. 3 figs

  12. A study of natural circulation cooling using a flow visualization rig

    International Nuclear Information System (INIS)

    Bowman, W.C.; Ferch, R.L.; Omar, A.M.

    1985-01-01

    A flow visualization rig has been built at Monserco Limited to provide visual insight into the thermalhydraulic phenomena which occur during single phase and two phase thermosyphoning in a figure-of-eight heat transport loop. Tests performed with the rig have provided design information for the scaling and instrumentation of a high pressure rig being investigated for simulating CANDU reactor conditions during natural circulation cooling. A videotape was produced, for viewing at this presentation, to show important thermalhydraulic features of the thermosyphoning process. The rig is a standard figure-of-eight loop with two steam generators and three heated channels per pass. An elevated surge tank open to atmosphere was used for pressure control. Two variable speed pumps provided forced circulation for warming up the rig, and for establishing the desired initial conditions for testing. Test rig power could be varied between 0 and 15 kW

  13. In Vivo Visualizing the IFN-β Response Required for Tumor Growth Control in a Therapeutic Model of Polyadenylic-Polyuridylic Acid Administration.

    Science.gov (United States)

    Nocera, David Andrés; Roselli, Emiliano; Araya, Paula; Nuñez, Nicolás Gonzalo; Lienenklaus, Stefan; Jablonska, Jadwiga; Weiss, Siegfried; Gatti, Gerardo; Brinkmann, Melanie M; Kröger, Andrea; Morón, Gabriel; Maccioni, Mariana

    2016-03-15

    The crucial role that endogenously produced IFN-β plays in eliciting an immune response against cancer has recently started to be elucidated. Endogenous IFN-β has an important role in immune surveillance and control of tumor development. Accordingly, the role of TLR agonists as cancer therapeutic agents is being revisited via the strategy of intra/peritumoral injection with the idea of stimulating the production of endogenous type I IFN inside the tumor. Polyadenylic-polyuridylic acid (poly A:U) is a dsRNA mimetic explored empirically in cancer immunotherapy a long time ago with little knowledge regarding its mechanisms of action. In this work, we have in vivo visualized the IFN-β required for the antitumor immune response elicited in a therapeutic model of poly A:U administration. In this study, we have identified the role of host type I IFNs, cell populations that are sources of IFN-β in the tumor microenvironment, and other host requirements for tumor control in this model. One single peritumoral dose of poly A:U was sufficient to induce IFN-β, readily visualized in vivo. IFN-β production relied mainly on the activation of the transcription factor IFN regulatory factor 3 and the molecule UNC93B1, indicating that TLR3 is required for recognizing poly A:U. CD11c(+) cells were an important, but not the only source of IFN-β. Host type I IFN signaling was absolutely required for the reduced tumor growth, prolonged mice survival, and the strong antitumor-specific immune response elicited upon poly A:U administration. These findings add new perspectives to the use of IFN-β-inducing compounds in tumor therapy. Copyright © 2016 by The American Association of Immunologists, Inc.

  14. Low-visibility light-intensity laser-triggered release of entrapped calcein from 1,2-bis (tricosa-10,12-diynoyl-sn-glycero-3-phosphocholine liposomes is mediated through a type I photoactivation pathway

    Directory of Open Access Journals (Sweden)

    Yavlovich A

    2013-07-01

    only the Cal-G loaded photo-triggerable liposomes but not from Cal-B-loaded liposomes (≤10 µM H2O2. The Cal-G release from photo-triggerable liposomes was found to be significantly inhibited by ascorbic acid (AA, resulting in a 70%–80% reduction in Cal-G release. The extent of AA-mediated inhibition of Cal-G release from the liposomes also correlated with the consumption of AA. No AA consumption was detected in the 514 nm laser-exposed Cal B-loaded liposomes, thus confirming a role of photoactivation of Cal-G in liposome destabilization. Inclusion of 100 mM K3Fe(CN6 (a blocker of electron transfer in the liposomes substantially inhibited Cal-G release, whereas inclusion of 10 mM sodium azide (a blocker of singlet oxygen of type II photoreaction in the liposomes failed to block 514 nm laser-triggered Cal-G release. Taken together, we conclude that low-intensity 514 nm laser-triggered release of Cal-G from photo-triggerable liposomes involves the type I photoreaction pathway.Keywords: visible laser-triggered payload release, photo-agents, photopolymerizable phospholipids, photodynamic actions, reactive oxygen species

  15. Malarial pigment haemozoin, IFN-gamma, TNF-alpha, IL-1beta and LPS do not stimulate expression of inducible nitric oxide synthase and production of nitric oxide in immuno-purified human monocytes

    Directory of Open Access Journals (Sweden)

    Ceretto Monica

    2007-06-01

    unable to express iNOS and generate NOS metabolites even after stimulation with IFN-gamma or a cytokine-LSP mix that were very active on HZ-fed murine phagocytic lines. Present data do not support the hypothesis that monocytes are mediators of anti-parasitic defence in clinical malaria via activation of iNOS and production of NO, and suggest caution in extrapolating data obtained with murine or hybrid systems to human malaria.

  16. IFN-gamma-induced chemokines synergize with pertussis toxin to promote T cell entry to the central nervous system

    DEFF Research Database (Denmark)

    Millward, Jason M; Caruso, Maria; Campbell, Iain L

    2007-01-01

    Inflammation of the CNS, which occurs during multiple sclerosis and experimental autoimmune encephalomyelitis, is characterized by increased levels of IFN-gamma, a cytokine not normally expressed in the CNS. To investigate the role of IFN-gamma in CNS, we used intrathecal injection of a replication......-defective adenovirus encoding murine IFN-gamma (AdIFNgamma) to IFN-gamma-deficient (GKO) mice. This method resulted in stable, long-lived expression of IFN-gamma that could be detected in cerebrospinal fluid using ELISA and Luminex bead immunoassay. IFN-gamma induced expression in the CNS of message and protein...... was predominantly localized to meningeal and ependymal cells, and was also seen in astrocytes and microglia. IFN-gamma-induced chemokine expression did not lead to inflammation. However, when pertussis toxin was given i.p. to mice infected with the IFN-gamma vector, there was a dramatic increase in the number of T...

  17. Interferon alpha treatment stimulates interferon gamma expression in type I NKT cells and enhances their antiviral effect against hepatitis C virus.

    Science.gov (United States)

    Miyaki, Eisuke; Hiraga, Nobuhiko; Imamura, Michio; Uchida, Takuro; Kan, Hiromi; Tsuge, Masataka; Abe-Chayama, Hiromi; Hayes, C Nelson; Makokha, Grace Naswa; Serikawa, Masahiro; Aikata, Hiroshi; Ochi, Hidenori; Ishida, Yuji; Tateno, Chise; Ohdan, Hideki; Chayama, Kazuaki

    2017-01-01

    Interferon (IFN) inhibits hepatitis C virus (HCV) replication through up-regulation of intrahepatic IFN-stimulated gene expression but also through activation of host immune cells. In the present study, we analyzed the immune cell-mediated antiviral effects of IFN-α using HCV-infected mice. Urokinase-type plasminogen activator (uPA)-severe combined immunodeficiency (SCID) mice with transplanted human hepatocytes were infected with genotype 1b HCV and injected with human peripheral blood mononuclear cells (PBMCs). IFN-α treatment following human PBMC transplantation resulted in a significant reduction in serum HCV RNA titers and a higher human CD45-positive mononuclear cell chimerism compared to mice without human PBMC transplantation. In mice with human PBMCs treated with IFN-α, serum concentrations of IFN-γ increased, and natural killer T (NKT) cells, especially type I NKT cells, produced IFN-γ. Mice in which IFN-γ signaling was blocked using antibody or in which transplanted PBMCs were depleted for type I NKT cells showed similar levels of anti-HCV effect compared with mice treated only with IFN-α. These results show that IFN-α stimulates IFN-γ expression in type 1 NKT cells and enhances the inhibition of HCV replication. We propose that type 1 NKT cells might represent a new therapeutic target for chronic hepatitis C patients.

  18. Coordinate induction of IFN-α and -γ by SARS-CoV also in the absence of virus replication

    International Nuclear Information System (INIS)

    Castilletti, Concetta; Bordi, Licia; Lalle, Eleonora; Rozera, Gabriella; Poccia, Fabrizio; Agrati, Chiara; Abbate, Isabella; Capobianchi, Maria R.

    2005-01-01

    Background:: Severe acute respiratory syndrome (SARS) is an emerging infection caused by a novel coronavirus known as SARS-CoV, characterized by an over-exuberant immune response with lung lymphomononuclear cells infiltration and proliferation that may account for tissue damage more than the direct effect of viral replication. This study is aimed at investigating the capability of SARS-CoV to activate IFN-α and -γ expression in lymphomonocytes (PBMC) from healthy donors, evaluating whether viral replication is necessary for this activation. Results:: SARS-CoV virus is able to induce both IFN-α and -γ mRNA accumulation and protein release in a dose-dependent manner, MOI 10 being the most effective. The time course curve indicated that IFN-α mRNA induction peaked at 24 h.p.i,. whereas IFN-γ mRNA was still increasing at 48 h.p.i. Released IFN (both types) reached a plateau after 24-48 h.p.i. and remained rather stable over a 5-day period. A transient peak of negative strand viral RNA was detected after 1-2 days of infection, but neither infectious virus progeny yield nor newly produced viral genomic RNA could be evidenced in infected cultures, even after prolonged observation time (up to 13 days). Cocultivation of PBMC with fixed SARS-CoV-infected Vero cells was even more efficient than exposure to live virus in eliciting IFN-α and -γ induction. A combination of IFN-α and -γ strongly inhibited SARS-CoV replication in Vero cells, while the single cytokines were much less effective. Conclusions:: This study provides evidence that SARS-CoV is able to induce in normal PBMC a coordinate induction of IFN-α and -γ gene expression. Virus replication is not necessary for IFN induction since efficient IFN expression could be obtained also by the cocultivation of normal PBMC with fixed SARS-CoV-infected cells. Concomitant activation of IFN-α and -γ gene expression by SARS-CoV in vivo may be relevant for the pathogenesis of the disease, both for the possible

  19. Changes of serum IL-2, IL-4, IL-10 and IFN-γ levels after treatment with 131I-17-allylamino-17-demethoxygeldanamycin in VX2 rabbit models

    International Nuclear Information System (INIS)

    Gao Wen; Liu Lu; Zhou Yun

    2007-01-01

    Objective: To study the influence of 131 I-17-allylamino-17-demethoxygeldanamycin( 131 I-17-AAG) therapy on immune function in VX2 rabbit models with transplanted liver cancer. Methods: Serum IL-2, IL-4, IL-10 and IFN-γ levels were measured with RIA in 8 VX2 rabbit models with transplanted liver cancer 1-2 weeks after 10mCi 131 I-17-AAG treatment as well as in 8 controls rabbits (models with tumor but without treatment). Results: 1 week after 10mCi 131 I treatment, the serum IL - 2 and IFN-γ levels were significantly lower in the treated rabbits than those in controls (P 0.05). Serum IL-4 and IL-10 levels in the treated rabbits (both at 1 and 2 week) were not significantly different from those in controls (P>0.05). Conclusion: 131 I-17-AAG treatment had transient effects on cellular immunity with no influence on humoral immunity. As a whole, it is a safe to treat VX2 rabbit models with this preparation. (authors)

  20. Species-independent bioassay for sensitive quantification of antiviral type I interferons

    Directory of Open Access Journals (Sweden)

    Penski Nicola

    2010-02-01

    Full Text Available Abstract Background Studies of the host response to infection often require quantitative measurement of the antiviral type I interferons (IFN-α/β in biological samples. The amount of IFN is either determined via its ability to suppress a sensitive indicator virus, by an IFN-responding reporter cell line, or by ELISA. These assays however are either time-consuming and lack convenient readouts, or they are rather insensitive and restricted to IFN from a particular host species. Results An IFN-sensitive, Renilla luciferase-expressing Rift Valley fever virus (RVFV-Ren was generated using reverse genetics. Human, murine and avian cells were tested for their susceptibility to RVFV-Ren after treatment with species-specific IFNs. RVFV-Ren was able to infect cells of all three species, and IFN-mediated inhibition of viral reporter activity occurred in a dose-dependent manner. The sensitivity limit was found to be 1 U/ml IFN, and comparison with a standard curve allowed to determine the activity of an unknown sample. Conclusions RVFV-Ren replicates in cells of several species and is highly sensitive to pre-treatment with IFN. These properties allowed the development of a rapid, sensitive, and species-independent antiviral assay with a convenient luciferase-based readout.

  1. LWR primary coolant pipe rupture test rig

    International Nuclear Information System (INIS)

    Yoshitoshi, Shyoji

    1978-01-01

    The rupture test rig for primary coolant pipes is constructed in the Japan Atomic Energy Research Institute to verify the reliability of the primary coolant pipes for both PWRs and BWRs. The planned test items consisted of reaction force test, restraint test, whip test, jet test and continuous release test. A pressure vessel of about 4 m 3 volume, a circulating pump, a pressurizer, a heater, an air cooler and the related instrumentation and control system are included in this test rig. The coolant test condition is 160 kg/cm 2 g, 325 deg C for PWR test, and 70 kg/cm 2 g, saturated water and steam for BWR test, 100 ton of test load for the ruptured pipe bore of 8B Schedule 160, and 20 lit/min. discharge during 20 h for continuous release of coolant. The maximum pit internal pressure was estimated for various pipe diameters and time under the PWR and BWR conditions. The spark rupturing device was adopted for the rupture mechanics in this test rig. The computer PANAFACOM U-300 is used for the data processing. This test rig is expected to operate in 1978 effectively for the improvement of reliability of LWR primary coolant pipes. (Nakai, Y.)

  2. Argentina's YPF outlines plan for sale of rigs

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports that state owned Yacimientos Petroliferos Fiscales (YPF) has unveiled the schedule it plans to follow to privatize oil and gas contract drilling in Argentine. YPF proposes to exit the drilling business by selling state owned drilling rigs, drill pipe, and accessories in a series of auctions beginning next month and lasting through first quarter 1993. YPF intends to open bids Dec. 16 for a completion unit and 30 drilling rigs, several working under contract. Bids will be opened during first quarter 1993 for new and used YPF drill pipe and collars, spare equipment and accessories, and an inventory of fishing tools said to be one of the largest in South America. Winners are to be notified immediately after each auction. YPF plans to hand over by Feb. 1, 1993, the rigs sold in December. Companies buying YPF drilling assets in first quarter 1993, the rigs sold in December. Companies buying YPF drilling assets in first quarter 1993 are to assume ownership by Mar. 24, 1993

  3. Essays on bid rigging

    NARCIS (Netherlands)

    Seres, Gyula

    2016-01-01

    Manipulating prices in auctions raises antitrust concerns. Collusion lowers the revenue of the auctioneer and creates information rents. Bid rigging is a prevalent phenomenon and the affected market is enormous. Public procurement amounts to between 10 and 25 percent of national GDP in

  4. Neutrophils responsive to endogenous IFN-beta regulate tumor angiogenesis and growth in a mouse tumor model.

    Science.gov (United States)

    Jablonska, Jadwiga; Leschner, Sara; Westphal, Kathrin; Lienenklaus, Stefan; Weiss, Siegfried

    2010-04-01

    Angiogenesis is a hallmark of malignant neoplasias, as the formation of new blood vessels is required for tumors to acquire oxygen and nutrients essential for their continued growth and metastasis. However, the signaling pathways leading to tumor vascularization are not fully understood. Here, using a transplantable mouse tumor model, we have demonstrated that endogenous IFN-beta inhibits tumor angiogenesis through repression of genes encoding proangiogenic and homing factors in tumor-infiltrating neutrophils. We determined that IFN-beta-deficient mice injected with B16F10 melanoma or MCA205 fibrosarcoma cells developed faster-growing tumors with better-developed blood vessels than did syngeneic control mice. These tumors displayed enhanced infiltration by CD11b+Gr1+ neutrophils expressing elevated levels of the genes encoding the proangiogenic factors VEGF and MMP9 and the homing receptor CXCR4. They also expressed higher levels of the transcription factors c-myc and STAT3, known regulators of VEGF, MMP9, and CXCR4. In vitro, treatment of these tumor-infiltrating neutrophils with low levels of IFN-beta restored expression of proangiogenic factors to control levels. Moreover, depletion of these neutrophils inhibited tumor growth in both control and IFN-beta-deficient mice. We therefore suggest that constitutively produced endogenous IFN-beta is an important mediator of innate tumor surveillance. Further, we believe our data help to explain the therapeutic effect of IFN treatment during the early stages of cancer development.

  5. The DNA sensor, cyclic GMP-AMP synthase, is essential for induction of IFN-β during Chlamydia trachomatis infection.

    Science.gov (United States)

    Zhang, Yugen; Yeruva, Laxmi; Marinov, Anthony; Prantner, Daniel; Wyrick, Priscilla B; Lupashin, Vladimir; Nagarajan, Uma M

    2014-09-01

    IFN-β has been implicated as an effector of oviduct pathology resulting from genital chlamydial infection in the mouse model. In this study, we investigated the role of cytosolic DNA and engagement of DNA sensors in IFN-β expression during chlamydial infection. We determined that three-prime repair exonuclease-1, a host 3' to 5' exonuclease, reduced IFN-β expression significantly during chlamydial infection using small interfering RNA and gene knockout fibroblasts, implicating cytosolic DNA as a ligand for this response. The DNA sensor cyclic GMP-AMP synthase (cGAS) has been shown to bind cytosolic DNA to generate cyclic GMP-AMP, which binds to the signaling adaptor stimulator of IFN genes (STING) to induce IFN-β expression. We determined that cGAS is required for IFN-β expression during chlamydial infection in multiple cell types. Interestingly, although infected cells deficient for STING or cGAS alone failed to induce IFN-β, coculture of cells depleted for either STING or cGAS rescued IFN-β expression. These data demonstrate that cyclic GMP-AMP produced in infected cGAS(+)STING(-) cells can migrate into adjacent cells via gap junctions to function in trans in cGAS(-)STING(+) cells. Furthermore, we observed cGAS localized in punctate regions on the cytosolic side of the chlamydial inclusion membrane in association with STING, indicating that chlamydial DNA is most likely recognized outside the inclusion as infection progresses. These novel findings provide evidence that cGAS-mediated DNA sensing directs IFN-β expression during Chlamydia trachomatis infection and suggest that effectors from infected cells can directly upregulate IFN-β expression in adjacent uninfected cells during in vivo infection, contributing to pathogenesis. Copyright © 2014 by The American Association of Immunologists, Inc.

  6. The development of fuel pins and material specimens mixed loading irradiation test rig in the experimental fast reactor Joyo. The development of the fuel-material hybrid rig

    International Nuclear Information System (INIS)

    Oyamatsu, Yasuko; Someya, Hiroyuki

    2013-02-01

    In the experimental fast reactor Joyo, there were many tests using the irradiation rigs that it was possible to be set irradiation conditions for each compartment independently. In case of no alternative fuel element to irradiate after unloading the irradiated compartments, the irradiation test was restarted with the dummy compartment which the fuel elements was not mounted. If the material specimens are mounted in this space, it is possible to use the irradiation space effectively. For these reasons, the irradiation rig (hybrid rig) is developed that is consolidated with material specimens compartment and fuel elements compartment. Fuel elements and material specimens differ greatly with heat generation, so that the most important issue in developing of hybrid rig is being able to distribute appropriately the coolant flow which satisfies irradiation conditions. The following is described by this report. (1) It was confirmed that the flow distribution of loading the same irradiation rig with the compartment from which a flow demand differs could be satisfied. (2) It was confirmed that temperature setting range of hybrid rig could be equivalent to that of irradiation condition. (3) By standardizing the coolant entrance structure of the compartment lower part, the prospect which can perform easily recombination of the compartment from which a type differs between irradiation rigs was acquired. (author)

  7. Enhanced targeted integration mediated by translocated I-SceI during the Agrobacterium mediated transformation of yeast.

    Science.gov (United States)

    Rolloos, Martijn; Hooykaas, Paul J J; van der Zaal, Bert J

    2015-02-09

    Agrobacterium mediated transformation (AMT) has been embraced by biotechnologists as the technology of choice to introduce or alter genetic traits of plants. However, in plants it is virtually impossible to predetermine the integration site of the transferred T-strand unless one is able to generate a double stranded break (DSB) in the DNA at the site of interest. In this study, we used the model organism Saccharomyces cerevisiae to investigate whether the Agrobacterium mediated translocation of site-specific endonucleases via the type IV secretion system (T4SS), concomitantly with T-DNA transfer is possible and whether this can improve the gene targeting efficiency. In addition to that, the effect of different chromatin states on targeted integration, was investigated. It was found that Agrobacterium mediated translocation of the homing endonuclease I-SceI has a positive effect on the integration of T-DNA via the homologous repair (HR) pathway. Furthermore, we obtained evidence that nucleosome removal has a positive effect on I-SceI facilitated T-DNA integration by HR. Reversely; inducing nucleosome formation at the site of integration removes the positive effect of translocated I-SceI on T-DNA integration.

  8. Interferon-gamma (IFN-γ-mediated retinal ganglion cell death in human tyrosinase T cell receptor transgenic mouse.

    Directory of Open Access Journals (Sweden)

    Shahid Husain

    Full Text Available We have recently demonstrated the characterization of human tyrosinase TCR bearing h3T-A2 transgenic mouse model, which exhibits spontaneous autoimmune vitiligo and retinal dysfunction. The purpose of current study was to determine the role of T cells and IFN-γ in retina dysfunction and retinal ganglion cell (RGC death using this model. RGC function was measured by pattern electroretinograms (ERGs in response to contrast reversal of patterned visual stimuli. RGCs were visualized by fluorogold retrograde-labeling. Expression of CD3, IFN-γ, GFAP, and caspases was measured by immunohistochemistry and Western blotting. All functional and structural changes were measured in 12-month-old h3T-A2 mice and compared with age-matched HLA-A2 wild-type mice. Both pattern-ERGs (42%, p = 0.03 and RGC numbers (37%, p = 0.0001 were reduced in h3T-A2 mice when compared with wild-type mice. The level of CD3 expression was increased in h3T-A2 mice (h3T-A2: 174 ± 27% vs. HLA-A2: 100%; p = 0.04. The levels of effector cytokine IFN-γ were also increased significantly in h3T-A2 mice (h3T-A2: 189 ± 11% vs. HLA-A2: 100%; p = 0.023. Both CD3 and IFN-γ immunostaining were increased in nerve fiber (NF and RGC layers of h3T-A2 mice. In addition, we have seen a robust increase in GFAP staining in h3T-A2 mice (mainly localized to NF layer, which was substantially reduced in IFN-γ ((-/- knockout h3T-A2 mice. We also have seen an up-regulation of caspase-3 and -9 in h3T-A2 mice. Based on our data we conclude that h3T-A2 transgenic mice exhibit visual defects that are mostly associated with the inner retinal layers and RGC function. This novel h3T-A2 transgenic mouse model provides opportunity to understand RGC pathology and test neuroprotective strategies to rescue RGCs.

  9. Role of 4-1BB receptor in the control played by CD8(+ T cells on IFN-gamma production by Mycobacterium tuberculosis antigen-specific CD4(+ T Cells.

    Directory of Open Access Journals (Sweden)

    Carla Palma

    Full Text Available BACKGROUND: Antigen-specific IFN-gamma producing CD4(+ T cells are the main mediators of protection against Mycobacterium tuberculosis infection both under natural conditions and following vaccination. However these cells are responsible for lung damage and poor vaccine efficacy when not tightly controlled. Discovering new tools to control nonprotective antigen-specific IFN-gamma production without affecting protective IFN-gamma is a challenge in tuberculosis research. METHODS AND FINDINGS: Immunization with DNA encoding Ag85B, a candidate vaccine antigen of Mycobacterium tuberculosis, elicited in mice a low but protective CD4(+ T cell-mediated IFN-gamma response, while in mice primed with DNA and boosted with Ag85B protein a massive increase in IFN-gamma response was associated with loss of protection. Both protective and non-protective Ag85B-immunization generated antigen-specific CD8(+ T cells which suppressed IFN-gamma-secreting CD4(+ T cells. However, ex vivo ligation of 4-1BB, a member of TNF-receptor super-family, reduced the massive, non-protective IFN-gamma responses by CD4(+ T cells in protein-boosted mice without affecting the low protective IFN-gamma-secretion in mice immunized with DNA. This selective inhibition was due to the induction of 4-1BB exclusively on CD8(+ T cells of DNA-primed and protein-boosted mice following Ag85B protein stimulation. The 4-1BB-mediated IFN-gamma inhibition did not require soluble IL-10, TGF-beta, XCL-1 and MIP-1beta. In vivo Ag85B stimulation induced 4-1BB expression on CD8(+ T cells and in vivo 4-1BB ligation reduced the activation, IFN-gamma production and expansion of Ag85B-specific CD4(+ T cells of DNA-primed and protein-boosted mice. CONCLUSION/SIGNIFICANCE: Antigen-specific suppressor CD8(+ T cells are elicited through immunization with the mycobacterial antigen Ag85B. Ligation of 4-1BB receptor further enhanced their suppressive activity on IFN-gamma-secreting CD4(+ T cells. The selective

  10. RIG-I Helicase-Independent Pathway in Sendai Virus-Activated Dendritic Cells Is Critical for Preventing Lung Metastasis of AT6.3 Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Tomonori Kato

    2010-11-01

    Full Text Available We recently demonstrated highly efficient antitumor immunity against dermal tumors of B16F10 murine melanoma with the use of dendritic cells (DCs activated by replication-competent, as well as nontransmissible-type, recombinant Sendai viruses (rSeV, and proposed a new concept, “immunostimulatory virotherapy,” for cancer immunotherapy. However, there has been little information on the efficacies of thismethod: 1 inmore clinically relevant situations including metastatic diseases, 2 on other tumor types and other animal species, and 3 on the related molecular/cellular mechanisms. In this study, therefore, we investigated the efficacy of vaccinating DCs activated by fusion gene-deleted nontransmissible rSeV on a rat model of lung metastasis using a highly malignant subline of Dunning R-3327 prostate cancer, AT6.3. rSeV/dF-green fluorescent protein (GFP-activated bone marrow-derived DCs (rSeV/dF-GFP-DC, consistent with results previously observed in murine DCs. Vaccination of rSeV/dF-GFP-DC was highly effective at preventing lung metastasis after intravenous loading of R-3327 tumor cells, compared with the effects observed with immature DCs or lipopolysaccharide-activated DCs. Interestingly, neither CTL activity nor DC trafficking showed any apparent difference among groups. Notably, rSeV/dF-DCs expressing a dominant-negative mutant of retinoic acid-inducible gene I (RIG-I (rSeV/dF-RIGIC-DC, an RNA helicase that recognizes the rSeV genome for inducing type I interferons, largely lost the expression of proinflammatory cytokines without any impairment of antitumor activity. These results indicate the essential role of RIG-I-independent signaling on antimetastatic effect induced by rSeV-activated DCs and may provide important insights to DC-based immunotherapy for advanced malignancies.

  11. Lapland longspur mortality at an oil well drilling rig site, Laramie County, Wyoming

    Science.gov (United States)

    Ramirez, Pedro; Dickerson, Kimberly K.; Lindstrom, Jim; Meteyer, Carol U.; Darrah, Scott

    2015-01-01

    Two hundred fifty-one Lapland longspur (Calcarius lapponicus) carcasses were recovered around an oil well drilling rig in Laramie County, Wyoming, USA, on December 13–14, 2010, apparent victims of a winter storm and “light entrapment” from the lights on the drilling rig during foggy conditions. We found Lapland longspur carcasses distributed around the drilling rig from 33 m to 171 m. Investigators did not find evidence of bird carcasses on the drilling rig deck or equipment immediately adjacent to the drilling rig. We ruled out chemical toxins and disease as a cause of mortality. Weather conditions, the circular depositional pattern of carcasses around the drilling rig, and bird necropsy results led investigators to conclude that the Lapland longspur mortality was the result of the migrating birds entering the area illuminated by the drilling rig lights in freezing fog and the birds repeatedly circling the drilling rig until they fell to the ground in exhaustion and dying from subsequent trauma. Further research is needed to understand how to most effectively adjust lighting of onshore drilling rigs to reduce the potential for avian light entrapment. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  12. Professional development of new rig supervisors a must

    International Nuclear Information System (INIS)

    Nordt, D.P.; Stone, M.S.

    1992-01-01

    This paper reports that because the number of drilling personnel has dropped dramatically over the last decade, many operators now face a shortage of competent rig supervisors. To be effective, the rig supervisor must develop a knowledge of drilling operations, apply optimization techniques to improve drilling performance, demand safe work practices, and protect the environment. Petroleum engineering degree programs and industry training programs can teach the rig supervisor specific technical and management skills; however, traditionally, the supervisor trainee shadows an experienced company man to learn how to direct a drilling operation. The success of this method depends not only on the skills and learning capabilities of the trainee but also on the trainer's time, motivation, knowledge, and ability to teach the skills necessary to direct drilling activities

  13. Drilling rig

    Energy Technology Data Exchange (ETDEWEB)

    Galiopa, A A; Yegorov, E K

    1981-01-04

    A drilling rig is proposed which contains a tower, lifter in the form of n infinite chain, and mobile rotator with holding device connected to the chain, and pipe holder. In order to accelerate the auxiliary operations to move the drilling string and unloaded rotator, the rotator is equipped with a clamp with means for transverse connection of it to both branches of the chain, while the pipe holders equipped with a clamp with means of connecting it to one of the branches of the chain.

  14. Identification and function analysis of canine stimulator of interferon gene (STING).

    Science.gov (United States)

    Zhang, Yuxiang; Zhu, Mengyan; Li, Gairu; Liu, Jie; Zhai, Xiaofeng; Wang, Ruyi; Zhang, Junyan; Xing, Gang; Gu, Jinyan; Yan, Liping; Lei, Jing; Sun, Haifeng; Shi, Zhiyu; Liu, Fei; Hu, Boli; Su, Shuo; Zhou, Jiyong

    2017-12-01

    Stimulator of interferon gene (STING) plays an important role in the cyclic GMP-AMP synthase (cGAS)-mediated activation of type I IFN responses. In this study, we identified and cloned canine STING gene. Full-length STING encodes a 375 amino acid product that shares the highest similarity with feline STING. Highest levels of mRNA of canine STING were detected in the spleen and lungs while the lowest levels in the heart and muscle. Analysis of its cellular localization showed that STING is localizes to the endoplasmic reticulum. STING overexpression induced the IFN response via the IRF3 and NF-κB pathways and up-regulated the expression of ISG15 and viperin. However, knockdown of STING did not inhibit the IFN-β response triggered by poly(dA:dT), poly(I:C), or SeV. Finally, overexpression of STING significantly inhibited the replication of canine influenza virus H3N2. Collectively, our findings indicate that STING is involved in the regulation of the IFN-β pathway in canine. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Flow Rate Measurement in Multiphase Flow Rig: Radiotracer and Conventional

    International Nuclear Information System (INIS)

    Nazrul Hizam Yusoff; Noraishah Othman; Nurliyana Abdullah; Amirul Syafiq Mohd Yunos; Rasif Mohd Zain; Roslan Yahya

    2015-01-01

    Applications of radiotracer technology are prevalent throughout oil refineries worldwide, and this industry is one of the main users and beneficiaries of the technology. Radioactive tracers have been used to a great extent in many applications i.e. flow rate measurement, RTD, plant integrity evaluation and enhancing oil production in oil fields. Chemical and petrochemical plants are generally continuously operating and technically complex where the radiotracer techniques are very competitive and largely applied for troubleshooting inspection and process analysis. Flow rate measurement is a typical application of radiotracers. For flow measurements, tracer data are important, rather than the RTD models. Research is going on in refining the existing methods for single phase flow measurement, and in developing new methods for multiphase flow without sampling. The tracer techniques for single phase flow measurements are recognized as ISO standards. This paper presents technical aspect of laboratory experiments, which have been carried out using Molybdenum-99 - Mo99 (radiotracer) to study and determine the flow rate of liquid in multiphase flow rig. The multiphase flow rig consists of 58.7 m long and 20 cm diameter pipeline that can accommodate about 0.296 m 3 of liquid. Tap water was used as liquid flow in pipeline and conventional flow meters were also installed at the flow rig. The flow rate results; radiotracer and conventional flow meter were compared. The total count method was applied for radiotracer technique and showed the comparable results with conventional flow meter. (author)

  16. Hot corrosion testing of Ni-based alloys and coatings in a modified Dean rig

    Science.gov (United States)

    Steward, Jason Reid

    Gas turbine blades are designed to withstand a variety of harsh operating conditions. Although material and coating improvements are constantly administered to increase the mean time before turbine refurbishment or replacement, hot corrosion is still considered as the major life-limiting factor in many industrial and marine gas turbines. A modified Dean rig was designed and manufactured at Tennessee Technological University to simulate the accelerated hot corrosion conditions and to conduct screening tests on the new coatings on Ni-based superalloys. Uncoated Ni-based superalloys, Rene 142 and Rene 80, were tested in the modified Dean rig to establish a testing procedure for Type I hot corrosion. The influence of surface treatments on the hot corrosion resistance was then investigated. It was found that grit-blasted specimens showed inferior hot corrosion resistance than that of the polished counterpart. The Dean rig was also used to test model MCrAlY alloys, pack cementation NiAl coatings, and electro-codeposited MCrAlY coatings. Furthermore, the hot corrosion attack on the coated-specimens were also assessed using a statistical analysis approach.

  17. Challenges associated with pre-border management of biofouling on oil rigs.

    Science.gov (United States)

    Hopkins, Grant A; Forrest, Barrie M

    2010-11-01

    The potential for oil rigs to transport diverse, reef-like communities around the globe makes them high risk vectors for the inadvertent spread of non-indigenous species (NIS). This paper describes two case studies where a suite of pre-border management approaches was applied to semi-submersible drilling rigs. In the first case study, a drilling rig was defouled in-water prior to departure from New Zealand to Australia. Risk mitigation measures were successful in reducing biosecurity risks to the recipient region, but they resulted in the unintentional introduction of the non-indigenous brown mussel (Perna perna) to New Zealand when the rig was defouled in-water by divers. In the second case study, lessons learned from this high-profile incursion resulted in a more structured approach to pre-border management, and this serves as a useful template for future rig transfers. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Study in flow rig by using radiotracer

    International Nuclear Information System (INIS)

    Widatalla, R. K.

    2012-06-01

    Application of radioisotope technology have proved itself to be effective techniques for troubleshooting and optimizing industrial process in petrochemical industry In this study gamma scanning technique has been employed for better understanding of malfunctions by using the flow rig system. The scanning were carried out using 9 9mT C gamma radiation source with activity of 1 mCi and quantity of 5 ml to measure the flow rate for the water flow rig The experiment was repeated by reducing the data interval time to get more precise result. The investigations were also carried out using 5 ml of 9 9mT C with activity of 0.3 mCi for measuring the Residence Time Distribution (RTD) inside the flow rig tank which enables calculating the effective volume for the operating tank and its dead volume. The results proved that the technique is sensitive, reliable and can be adopted to investigate industrial reactors. (Author)

  19. A constructive presentation of rigged Hilbert spaces

    International Nuclear Information System (INIS)

    Celeghini, Enrico

    2015-01-01

    We construct a rigged Hilbert space for the square integrable functions on the line L2(R) adding to the generators of the Weyl-Heisenberg algebra a new discrete operator, related to the degree of the Hermite polynomials. All together, continuous and discrete operators, constitute the generators of the projective algebra io(2). L 2 (R) and the vector space of the line R are shown to be isomorphic representations of such an algebra and, as both these representations are irreducible, all operators defined on the rigged Hilbert spaces L 2 (R) or R are shown to belong to the universal enveloping algebra of io(2). The procedure can be extended to orthogonal and pseudo-orthogonal spaces of arbitrary dimension by tensorialization.Circumventing all formal problems the paper proposes a kind of toy model, well defined from a mathematical point of view, of rigged Hilbert spaces where, in contrast with the Hilbert spaces, operators with different cardinality are allowed. (paper)

  20. IFN-γ and TNF-α producing CD4+ T-cells in the blood after Mycoplasma hyosynoviae challenge of vaccinated pigs

    DEFF Research Database (Denmark)

    Riber, Ulla; Hansen, Mette Sif; Lauritsen, Klara Tølbøll

    In a vaccine trial against Mycoplasma hyosynoviae infection, pigs were vaccinated with formalin fixed whole-cell-antigen formulated with adjuvant DDA/TDB (SSI). Placebo pigs received adjuvant with saline. Vaccinations were performed at five and eight weeks of age, followed by an intranasal M....... hyosynoviae challenge inoculation three weeks later. Vaccination induced both antibodies and a cell-mediated immune response (CMI) in vaccinated pigs compared to placebo pigs as shown by M. hyosynoviae antigen (Ag) specific IFN-γ response in an IL-18 potentiated whole-blood IFN-γ stimulation assay (mean IFN......-γ level 1936 pg/ml vs. 82 pg/ml (p=0.0001)). A central memory T cell phenotype with polyfunctional capacity to produce all three cytokines IFN-γ, TNF-α and IL-2 has recently been linked to development of vaccine induced protection in several infections. In a subset of seven vaccinated pigs and four...

  1. The ATLAS Muon Trigger Performance in Run I and Initial Run II Performance

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00437899; The ATLAS collaboration

    2015-01-01

    Events with muons in the final state are an important signature for many physics topics at the Large Hadron Collider (LHC). An efficient trigger on muons and a detailed understanding of its performance are required. In 2012, the last year of Run I, the instantaneous luminosity of the LHC reached 7.7x1033 cm-2s-1 and the average number of events that occur in a same bunch crossing was 25. The ATLAS Muon trigger has successfully adapted to this changing environment by making use of isolation requirements, combined trigger signatures with electron and jet trigger objects, and by using so-called full-scan triggers, which make use of the full event information to search for di-lepton signatures, seeded by single lepton objects. A stable and highly efficient muon trigger was vital in the discovery of Higgs boson in 2012 and for many searches for new physics. The performance of muon triggers during the LHC Run 1 data-taking campaigns is presented, together with an overview and preliminary results of the new muon str...

  2. Melanoma cells treated with GGTI and IFN-gamma allow murine vaccination and enhance cytotoxic response against human melanoma cells.

    Directory of Open Access Journals (Sweden)

    Guillaume Sarrabayrouse

    Full Text Available BACKGROUND: Suboptimal activation of T lymphocytes by melanoma cells is often due to the defective expression of class I major histocompatibility antigens (MHC-I and costimulatory molecules. We have previously shown that geranylgeranyl transferase inhibition (done with GGTI-298 stimulates anti-melanoma immune response through MHC-I and costimulatory molecule expression in the B16F10 murine model [1]. METHODOLOGY/PRINCIPAL FINDINGS: In this study, it is shown that vaccination with mIFN-gand GGTI-298 pretreated B16F10 cells induces a protection against untreated tumor growth and pulmonary metastases implantation. Furthermore, using a human melanoma model (LB1319-MEL, we demonstrated that in vitro treatment with hIFN-gamma and GGTI-298 led to the up regulation of MHC-I and a costimulatory molecule CD86 and down regulation of an inhibitory molecule PD-1L. Co-culture experiments with peripheral blood mononuclear cells (PBMC revealed that modifications induced by hIFN-gamma and GGTI-298 on the selected melanoma cells, enables the stimulation of lymphocytes from HLA compatible healthy donors. Indeed, as compared with untreated melanoma cells, pretreatment with hIFN-gamma and GGTI-298 together rendered the melanoma cells more efficient at inducing the: i activation of CD8 T lymphocytes (CD8+/CD69+; ii proliferation of tumor-specific CD8 T cells (MelanA-MART1/TCR+; iii secretion of hIFN-gamma; and iv anti-melanoma specific cytotoxic cells. CONCLUSIONS/SIGNIFICANCE: These data indicate that pharmacological treatment of melanoma cell lines with IFN-gamma and GGTI-298 stimulates their immunogenicity and could be a novel approach to produce tumor cells suitable for vaccination and for stimulation of anti-melanoma effector cells.

  3. Type I interferons are associated with subclinical markers of cardiovascular disease in a cohort of systemic lupus erythematosus patients.

    Directory of Open Access Journals (Sweden)

    Emily C Somers

    Full Text Available Systemic lupus erythematosus (SLE patients have a striking increase in cardiovascular (CV comorbidity not fully explained by the Framingham risk score. Recent evidence from in vitro studies suggests that type I interferons (IFN could promote premature CV disease (CVD in SLE. We assessed the association of type I IFN signatures with functional and anatomical evidence of vascular damage, and with biomarkers of CV risk in a cohort of lupus patients without overt CVD.Serum type I IFN activity (induction of five IFN-inducible genes; IFIGs from 95 SLE patient and 38 controls was quantified by real-time PCR. Flow mediated dilatation (FMD of the brachial artery and carotid intima media thickness (CIMT were quantified by ultrasound, and coronary calcification by computed tomography. Serum vascular biomarkers were measured by ELISA. We evaluated the effect of type I IFNs on FMD, CIMT and coronary calcification by first applying principal components analysis to combine data from five IFIGs into summary components that could be simultaneously modeled. Three components were derived explaining 97.1% of the total IFIG variation. Multivariable linear regression was utilized to investigate the association between the three components and other covariates, with the outcomes of FMD and CIMT; zero-inflated Poisson regression was used for modeling of coronary calcification. After controlling for traditional CV risk factors, enhanced serum IFN activity was significantly associated with decreased endothelial function in SLE patients and controls (p<0.05 for component 3, increased CIMT among SLE patients (p<0.01 for components 1 and 2, and severity of coronary calcification among SLE patients (p<0.001 for component 3.Type I IFNs are independently associated with atherosclerosis development in lupus patients without history of overt CVD and after controlling for Framingham risk factors. This study further supports the hypothesis that type I IFNs promote premature

  4. Operating experience of a sodium rig following the ingress of oil

    Energy Technology Data Exchange (ETDEWEB)

    Bell, A C; Mehew, R D; Robertson, C M [UKAEA, Dounreay, Thurso, Caithness, Scotland (United Kingdom)

    1980-05-01

    The experience of operating the Small Water Leak Rig at Dounreay in the two years following the ingress into the sodium of silicone oil from the pump is reported. The carbon penetration into the rig pipework has been monitored and has been found to agree with a diffusion model. The predictions based on this model have enabled an operating strategy to be determined to allow continued operation of the rig. (author)

  5. Operating experience of a sodium rig following the ingress of oil

    International Nuclear Information System (INIS)

    Bell, A.C.; Mehew, R.D.; Robertson, C.M.

    1980-01-01

    The experience of operating the Small Water Leak Rig at Dounreay in the two years following the ingress into the sodium of silicone oil from the pump is reported. The carbon penetration into the rig pipework has been monitored and has been found to agree with a diffusion model. The predictions based on this model have enabled an operating strategy to be determined to allow continued operation of the rig. (author)

  6. Cytokines affecting CD4+T regulatory cells in transplant tolerance. II. Interferon gamma (IFN-γ) promotes survival of alloantigen-specific CD4+T regulatory cells.

    Science.gov (United States)

    Nomura, Masaru; Hodgkinson, Suzanne J; Tran, Giang T; Verma, Nirupama D; Robinson, Catherine; Plain, Karren M; Boyd, Rochelle; Hall, Bruce M

    2017-06-01

    CD4 + T cells that transfer alloantigen-specific transplant tolerance are short lived in culture unless stimulated with specific-donor alloantigen and lymphocyte derived cytokines. Here, we examined if IFN-γ maintained survival of tolerance transferring CD4 + T cells. Alloantigen-specific transplant tolerance was induced in DA rats with heterotopic adult PVG heart allografts by a short course of immunosuppression and these grafts functioned for >100days with no further immunosuppression. In previous studies, we found the CD4 + T cells from tolerant rats that transfer tolerance to an irradiated DA host grafted with a PVG heart, lose their tolerance transferring ability after 3days of culture, either with or without donor alloantigen, and effect rejection of specific-donor grafts. If cultures with specific-donor alloantigen are supplemented by supernatant from ConA activated lymphocytes the tolerance transferring cells survive, suggesting these cells depend on cytokines for their survival. In this study, we found addition of rIFN-γ to MLC with specific-donor alloantigen maintained the capacity of tolerant CD4 + T cells to transfer alloantigen-specific tolerance and their ability to suppress PVG allograft rejection mediated by co-administered naïve CD4 + T cells. IFN-γ suppressed the in vitro proliferation of tolerant CD4 + T cells. Tolerant CD4 + CD25 + T cells did not proliferate in MLC to PVG stimulator cells with no cytokine added, but did when IFN-γ was present. IFN-γ did not alter proliferation of tolerant CD4 + CD25 + T cells to third-party Lewis. Tolerant CD4 + CD25 + T cells' expression of IFN-γ receptor (IFNGR) was maintained in culture when IFN-γ was present. This study suggested that IFN-γ maintained tolerance mediating alloantigen-specific CD4 + CD25 + T cells. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  7. Transmission of HBV DNA Mediated by Ceramide-Triggered Extracellular Vesicles.

    Science.gov (United States)

    Sanada, Takahiro; Hirata, Yuichi; Naito, Yutaka; Yamamoto, Naoki; Kikkawa, Yoshiaki; Ishida, Yuji; Yamasaki, Chihiro; Tateno, Chise; Ochiya, Takahiro; Kohara, Michinori

    2017-03-01

    An extracellular vesicle (EV) is a nanovesicle that shuttles proteins, nucleic acids, and lipids, thereby influencing cell behavior. A recent crop of reports have shown that EVs are involved in infectious biology, influencing host immunity and playing a role in the viral life cycle. In the present work, we investigated the EV-mediated transmission of hepatitis B virus (HBV) infection. We investigated the EV-mediated transmission of HBV infection by using a HBV infectious culture system that uses primary human hepatocytes derived from humanized chimeric mice (PXB-cells). Purified EVs were isolated by ultracentrifugation. To analyze the EVs and virions, we used stimulated emission depletion microscopy. Purified EVs from HBV-infected PXB-cells were shown to contain HBV DNA and to be capable of transmitting HBV DNA to naive PXB-cells. These HBV-DNA-transmitting EVs were shown to be generated through a ceramide-triggered EV production pathway. Furthermore, we showed that these HBV-DNA-transmitting EVs were resistant to antibody neutralization; stimulated emission depletion microscopy showed that EVs lacked hepatitis B surface antigen, the target of neutralizing antibodies. These findings suggest that EVs harbor a DNA cargo capable of transmitting viral DNA into hepatocytes during HBV infection, representing an additional antibody-neutralization-resistant route of HBV infection.

  8. Learning from the Messengers: Innate Sensing of Viruses and Cytokine Regulation of Immunity — Clues for Treatments and Vaccines

    Directory of Open Access Journals (Sweden)

    Jesper Melchjorsen

    2013-01-01

    Full Text Available Virus infections are a major global public health concern, and only via substantial knowledge of virus pathogenesis and antiviral immune responses can we develop and improve medical treatments, and preventive and therapeutic vaccines. Innate immunity and the shaping of efficient early immune responses are essential for control of viral infections. In order to trigger an efficient antiviral defense, the host senses the invading microbe via pattern recognition receptors (PRRs, recognizing distinct conserved pathogen-associated molecular patterns (PAMPs. The innate sensing of the invading virus results in intracellular signal transduction and subsequent production of interferons (IFNs and proinflammatory cytokines. Cytokines, including IFNs and chemokines, are vital molecules of antiviral defense regulating cell activation, differentiation of cells, and, not least, exerting direct antiviral effects. Cytokines shape and modulate the immune response and IFNs are principle antiviral mediators initiating antiviral response through induction of antiviral proteins. In the present review, I describe and discuss the current knowledge on early virus–host interactions, focusing on early recognition of virus infection and the resulting expression of type I and type III IFNs, proinflammatory cytokines, and intracellular antiviral mediators. In addition, the review elucidates how targeted stimulation of innate sensors, such as toll-like receptors (TLRs and intracellular RNA and DNA sensors, may be used therapeutically. Moreover, I present and discuss data showing how current antimicrobial therapies, including antibiotics and antiviral medication, may interfere with, or improve, immune response.

  9. Andrographolide Restores Steroid Sensitivity To Block Lipopolysaccharide/IFN-γ-Induced IL-27 and Airway Hyperresponsiveness in Mice.

    Science.gov (United States)

    Liao, Wupeng; Tan, W S Daniel; Wong, W S Fred

    2016-06-01

    LPS and IFN-γ alone or in combination have been implicated in the development of steroid resistance. Combined LPS/IFN-γ strongly upregulates IL-27 production, which has been linked to steroid-resistant airway hyperresponsiveness (AHR). Andrographolide, a bioactive molecule isolated from the plant Andrographis paniculata, has demonstrated anti-inflammatory and antioxidant properties. The present study investigated whether andrographolide could restore steroid sensitivity to block LPS/IFN-γ-induced IL-27 production and AHR via its antioxidative property. The mouse macrophage cell line Raw 264.7, mouse primary lung monocytes/macrophages, and BALB/c mice were treated with LPS/IFN-γ, in the presence and absence of dexamethasone and/or andrographolide. Levels of IL-27 in vitro and in vivo were examined and mouse AHR was assessed. Dexamethasone alone failed to inhibit LPS/IFN-γ-induced IL-27 production and AHR in mice. Andrographolide significantly restored the suppressive effect of dexamethasone on LPS/IFN-γ-induced IL-27 mRNA and protein levels in the macrophage cell line and primary lung monocytes/macrophages, mouse bronchoalveolar lavage fluid and lung tissues, and AHR in mice. LPS/IFN-γ markedly reduced the nuclear level of histone deacetylase (HDAC)2, an essential epigenetic enzyme that mediates steroid anti-inflammatory action. LPS/IFN-γ also decreased total HDAC activity but increased the total histone acetyltransferase/HDAC activity ratio in mouse lungs. Andrographolide significantly restored nuclear HDAC2 protein levels and total HDAC activity, and it diminished the total histone acetyltransferase/HDAC activity ratio in mouse lungs exposed to LPS/IFN-γ, possibly via suppression of PI3K/Akt/HDAC2 phosphorylation, and upregulation of the antioxidant transcription factor NF erythroid-2-related factor 2 level and DNA binding activity. Our data suggest that andrographolide may have therapeutic value in resensitizing steroid action in respiratory disorders

  10. Role of interferon-gamma in the pathogenesis of LCMV-induced meningitis: unimpaired leucocyte recruitment, but deficient macrophage activation in interferon-gamma knock-out mice

    DEFF Research Database (Denmark)

    Nansen, A; Christensen, Jan Pravsgaard; Röpke, C

    1998-01-01

    , a viral peptide could also elicit a T cell mediated inflammatory response in virus-primed IFN-gamma knock-out mice, indicating that redundancy of this cytokine as a proinflammatory mediator is not restricted to inflammatory reactions triggered by an active infection. Thus, T cell mediated inflammation may...

  11. Recombinant IFN-γ from the bank vole Myodes glareolus: a novel tool for research on rodent reservoirs of zoonotic pathogens.

    Science.gov (United States)

    Torelli, Francesca; Zander, Steffen; Ellerbrok, Heinz; Kochs, Georg; Ulrich, Rainer G; Klotz, Christian; Seeber, Frank

    2018-02-12

    Rodent species like Myodes glareolus and Microtus spp. are natural reservoirs for many zoonotic pathogens causing human diseases and are gaining increasing interest in the field of eco-immunology as candidate animal models. Despite their importance the lack of immunological reagents has hampered research in these animal species. Here we report the recombinant production and functional characterization of IFN-γ, a central mediator of host's innate and adaptive immune responses, from the bank vole M. glareolus. Soluble dimeric recMgIFN-γ was purified in high yield from Escherichia coli. Its activity on M. glareolus and Microtus arvalis kidney cell lines was assessed by immunofluorescent detection of nuclear translocation and phosphorylation of the transcription factor STAT1. RecMgIFN-γ also induced expression of an IFN-γ-regulated innate immunity gene. Inhibition of vesicular stomatitis virus replication in vole cells upon recMgIFN-γ treatment provided further evidence of its biological activity. Finally, we established a recMgIFN-γ-responsive bank vole reporter cell line that allows the sensitive titration of the cytokine activity via a bioluminescence reporter assay. Taken together, we report valuable tools for future investigations on the immune response against zoonotic pathogens in their natural animal hosts, which might foster the development of novel animal models.

  12. Early endonuclease-mediated evasion of RNA sensing ensures efficient coronavirus replication.

    Directory of Open Access Journals (Sweden)

    Eveline Kindler

    2017-02-01

    Full Text Available Coronaviruses are of veterinary and medical importance and include highly pathogenic zoonotic viruses, such as SARS-CoV and MERS-CoV. They are known to efficiently evade early innate immune responses, manifesting in almost negligible expression of type-I interferons (IFN-I. This evasion strategy suggests an evolutionary conserved viral function that has evolved to prevent RNA-based sensing of infection in vertebrate hosts. Here we show that the coronavirus endonuclease (EndoU activity is key to prevent early induction of double-stranded RNA (dsRNA host cell responses. Replication of EndoU-deficient coronaviruses is greatly attenuated in vivo and severely restricted in primary cells even during the early phase of the infection. In macrophages we found immediate induction of IFN-I expression and RNase L-mediated breakdown of ribosomal RNA. Accordingly, EndoU-deficient viruses can retain replication only in cells that are deficient in IFN-I expression or sensing, and in cells lacking both RNase L and PKR. Collectively our results demonstrate that the coronavirus EndoU efficiently prevents simultaneous activation of host cell dsRNA sensors, such as Mda5, OAS and PKR. The localization of the EndoU activity at the site of viral RNA synthesis-within the replicase complex-suggests that coronaviruses have evolved a viral RNA decay pathway to evade early innate and intrinsic antiviral host cell responses.

  13. Advantages and limitations of remotely operated sea floor drill rigs

    Science.gov (United States)

    Freudenthal, T.; Smith, D. J.; Wefer, G.

    2009-04-01

    A variety of research targets in marine sciences including the investigation of gas hydrates, slope stability, alteration of oceanic crust, ore formation and palaeoclimate can be addressed by shallow drilling. However, drill ships are mostly used for deep drillings, both because the effort of building up a drill string from a drill ship to the deep sea floor is tremendous and control on drill bit pressure from a movable platform and a vibrating drill string is poor especially in the upper hundred meters. During the last decade a variety of remotely operated drill rigs have been developed, that are deployed on the sea bed and operated from standard research vessels. These developments include the BMS (Bentic Multicoring System, developed by Williamson and Associates, operated by the Japanese Mining Agency), the PROD (Portable Remotely Operated Drill, developed and operated by Benthic Geotech), the Rockdrill 2 (developed and operated by the British geological Survey) and the MeBo (German abbreviation for sea floor drill rig, developed and operated by Marum, University of Bremen). These drill rigs reach drilling depths between 15 and 100 m. For shallow drillings remotely operated drill rigs are a cost effective alternative to the services of drill ships and have the major advantage that the drilling operations are performed from a stable platform independent of any ship movements due to waves, wind or currents. Sea floor drill rigs can be deployed both in shallow waters and the deep sea. A careful site survey is required before deploying the sea floor drill rig. Slope gradient, small scale topography and soil strength are important factors when planning the deployment. The choice of drill bits and core catcher depend on the expected geology. The required drill tools are stored on one or two magazines on the drill rig. The MeBo is the only remotely operated drill rig world wide that can use wire line coring technique. This method is much faster than conventional

  14. Exogenous HIV-1 Nef upsets the IFN-γ-induced impairment of human intestinal epithelial integrity.

    Directory of Open Access Journals (Sweden)

    Maria Giovanna Quaranta

    Full Text Available The mucosal tissues play a central role in the transmission of HIV-1 infection as well as in the pathogenesis of AIDS. Despite several clinical studies reported intestinal dysfunction during HIV infection, the mechanisms underlying HIV-induced impairments of mucosal epithelial barrier are still unclear. It has been postulated that HIV-1 alters enterocytic function and HIV-1 proteins have been detected in several cell types of the intestinal mucosa. In the present study, we analyzed the effect of the accessory HIV-1 Nef protein on human epithelial cell line.We used unstimulated or IFN-γ-stimulated Caco-2 cells, as a model for homeostatic and inflamed gastrointestinal tracts, respectively. We investigated the effect of exogenous recombinant Nef on monolayer integrity analyzing its uptake, transepithelial electrical resistance, permeability to FITC-dextran and the expression of tight junction proteins. Moreover, we measured the induction of proinflammatory mediators. Exogenous Nef was taken up by Caco-2 cells, increased intestinal epithelial permeability and upset the IFN-γ-induced reduction of transepithelial resistance, interfering with tight junction protein expression. Moreover, Nef inhibited IFN-γ-induced apoptosis and up-regulated TNF-α, IL-6 and MIP-3α production by Caco-2 cells while down-regulated IL-10 production. The simultaneous exposure of Caco-2 cells to Nef and IFN-γ did not affect cytokine secretion respect to untreated cells. Finally, we found that Nef counteracted the IFN-γ induced arachidonic acid cascade.Our findings suggest that exogenous Nef, perturbing the IFN-γ-induced impairment of intestinal epithelial cells, could prolong cell survival, thus allowing for accumulation of viral particles. Our results may improve the understanding of AIDS pathogenesis, supporting the discovery of new therapeutic interventions.

  15. Computers make rig life extension an option

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The worldwide semisubmersible drilling rig fleet is approaching retirement. But replacement is not an attractive option even though dayrates are reaching record highs. In 1991, Schlumberger Sedco Forex managers decided that an alternative might exist if regulators and insurers could be convinced to extend rig life expectancy through restoration. Sedco Forex chose their No. 704 semisubmersible, an 18-year North Sea veteran, to test their process. The first step was to determine what required restoration, meaning fatigue life analysis of each weld on the huge vessel. If inspected, the task would be unacceptably time-consuming and of questionable accuracy. Instead a suite of computer programs modeled the stress seen by each weld, statistically estimated the sea states seen by the rig throughout its North Sea service and calibrated a beam-element model on which to run their computer simulations. The elastic stiffness of the structure and detailed stress analysis of each weld was performed with ANSYS, a commercially available finite-element analysis program. The use of computer codes to evaluate service life extension is described.

  16. Virus Infection Triggers MAVS Polymers of Distinct Molecular Weight

    Directory of Open Access Journals (Sweden)

    Natalia Zamorano Cuervo

    2018-01-01

    Full Text Available The mitochondrial antiviral signaling (MAVS adaptor protein is a central signaling hub required for cells to mount an antiviral response following virus sensing by retinoic acid-inducible gene I (RIG-I-like receptors. MAVS localizes in the membrane of mitochondria and peroxisomes and in mitochondrial-associated endoplasmic reticulum membranes. Structural and functional studies have revealed that MAVS activity relies on the formation of functional high molecular weight prion-like aggregates. The formation of protein aggregates typically relies on a dynamic transition between oligomerization and aggregation states. The existence of intermediate state(s of MAVS polymers, other than aggregates, has not yet been documented. Here, we used a combination of non-reducing SDS-PAGE and semi-denaturing detergent agarose gel electrophoresis (SDD-AGE to resolve whole cell extract preparations to distinguish MAVS polymerization states. While SDD-AGE analysis of whole cell extracts revealed the formation of previously described high molecular weight prion-like aggregates upon constitutively active RIG-I ectopic expression and virus infection, non-reducing SDS-PAGE allowed us to demonstrate the induction of lower molecular weight oligomers. Cleavage of MAVS using the NS3/4A protease revealed that anchoring to intracellular membranes is required for the appropriate polymerization into active high molecular weight aggregates. Altogether, our data suggest that RIG-I-dependent MAVS activation involves the coexistence of MAVS polymers with distinct molecular weights.

  17. Developmental test report, assessment of XT-70E percussion drill rig operation in tank farms

    International Nuclear Information System (INIS)

    Dougherty, L.F.

    1996-01-01

    The following report documents the testing of the XT-70E percussion drill rig for use in the 241-SX Tank Farm. The test is necessary to support evaluation of the safety and authorization level of the proposed activity of installing up to three new drywells in the 241- SX Tank Farm. The proposed activity plans to install drywells by percussion drilling 7 inch O.D./6 inch I.D. pipe in close proximity of underground storage tanks and associated equipment. The load transmitted from the drill rig's percussion hammer through the ground to the tank structure and equipment is not known and therefore testing is required to ensure the activity is safe and authorized

  18. Spontaneous focal activation of invariant natural killer T (iNKT cells in mouse liver and kidney

    Directory of Open Access Journals (Sweden)

    Zeng Jia

    2010-11-01

    Full Text Available Abstract Background Invariant natural killer T (iNKT cells differ from other T cells by their hyperactive effector T-cell status, in addition to the expression of NK lineage receptors and semi-invariant T-cell receptors. It is generally agreed that the immune phenotype of iNKT cells is maintained by repeated activation in peripheral tissues although no explicit evidence for such iNKT cell activity in vivo has so far been reported. Results We used an interferon (IFN-γ-inducible cytoplasmic protein, Irga6, as a histological marker for local IFN-γ production. Irga6 was intensely expressed in small foci of liver parenchymal cells and kidney tubular epithelium. Focal Irga6 expression was unaffected by germ-free status or loss of TLR signalling and was totally dependent on IFN-γ secreted by T cells in the centres of expression foci. These were shown to be iNKT cells by diagnostic T cell receptor usage and their activity was lost in both CD1 d and Jα-deficient mice. Conclusions This is the first report that supplies direct evidence for explicit activation events of NKT cells in vivo and raises issues about the triggering mechanism and consequences for immune functions in liver and kidney.

  19. The laboratory test rig with miniature jet engine to research aviation fuels combustion process

    Directory of Open Access Journals (Sweden)

    Gawron Bartosz

    2015-12-01

    Full Text Available This article presents laboratory test rig with a miniature turbojet engine (MiniJETRig – Miniature Jet Engine Test Rig, that was built in the Air Force Institute of Technology. The test rig has been developed for research and development works aimed at modelling and investigating processes and phenomena occurring in full scale jet engines. In the article construction of a test rig is described, with a brief discussion on the functionality of each of its main components. Additionally examples of measurement results obtained during the realization of the initial tests have been included, presenting the capabilities of the test rig.

  20. IT that works on the rig floor : computers on drilling rigs need to be certified and built with features that can handle the environment

    Energy Technology Data Exchange (ETDEWEB)

    Balsaver, N.

    2010-07-15

    This article discussed the design challenges faced in developing hazardous-location computers for rig-floor use and other recently introduced products from Laversab. Rig-floor computers must not only be certified as Zone-1 or Zone-2 compliant but must also have features that make them work dependably in an extreme environment, including a wide operating temperature range, an ability to withstand severe vibration, immunity to salt fog, a viewable display in bright daylight, networking capability, USB and serial interfaces, and touch screens. Size and weight has been a major obstacle, but recent innovations have made Zone-1 computers intrinsically safe (IS), making them much smaller and lighter. Wireless networking eliminates the need for installing copper and fibre-optic cabling, but the wireless interface must be strong enough to overcome the many obstructions that are typically present on oil rigs. The computer models described, including a Driller's Display designed to be IS for Zone-1 applications and a Directional MWD Surface System designed for Zone-2 applications, provide solutions to the challenges of a working rig-floor environment. 3 figs.

  1. Macrophage-mediated gliadin degradation and concomitant IL-27 production drive IL-10- and IFN-γ-secreting Tr1-like-cell differentiation in a murine model for gluten tolerance.

    Science.gov (United States)

    van Leeuwen, M A; Costes, L M M; van Berkel, L A; Simons-Oosterhuis, Y; du Pré, M F; Kozijn, A E; Raatgeep, H C; Lindenbergh-Kortleve, D J; van Rooijen, N; Koning, F; Samsom, J N

    2017-05-01

    Celiac disease is caused by inflammatory T-cell responses against the insoluble dietary protein gliadin. We have shown that, in humanized mice, oral tolerance to deamidated chymotrypsin-digested gliadin (CT-TG2-gliadin) is driven by tolerogenic interferon (IFN)-γ- and interleukin (IL)-10-secreting type 1 regulatory T-like cells (Tr1-like cells) generated in the spleen but not in the mesenteric lymph nodes. We aimed to uncover the mechanisms underlying gliadin-specific Tr1-like-cell differentiation and hypothesized that proteolytic gliadin degradation by splenic macrophages is a decisive step in this process. In vivo depletion of macrophages caused reduced differentiation of splenic IFN-γ- and IL-10-producing Tr1-like cells after CT-TG2-gliadin but not gliadin peptide feed. Splenic macrophages, rather than dendritic cells, constitutively expressed increased mRNA levels of the endopeptidase Cathepsin D; macrophage depletion significantly reduced splenic Cathepsin D expression in vivo and Cathepsin D efficiently degraded recombinant γ-gliadin in vitro. In response to CT-TG2-gliadin uptake, macrophages enhanced the expression of Il27p28, a cytokine that favored differentiation of gliadin-specific Tr1-like cells in vitro, and was previously reported to increase Cathepsin D activity. Conversely, IL-27 neutralization in vivo inhibited splenic IFN-γ- and IL-10-secreting Tr1-like-cell differentiation after CT-TG2-gliadin feed. Our data infer that endopeptidase mediated gliadin degradation by macrophages and concomitant IL-27 production drive differentiation of splenic gliadin-specific Tr1-like cells.

  2. Local IFN-gamma therapy of HPV16-associated tumours

    Czech Academy of Sciences Publication Activity Database

    Mikyšková, Romana; Bieblová, Jana; Šímová, Jana; Indrová, Marie; Jandlová, Táňa; Vonka, V.; Šmahel, M.; Bubeník, Jan; Mendoza, Luis

    2003-01-01

    Roč. 49, č. 1 (2003), s. 26-32 ISSN 0015-5500 R&D Projects: GA MZd NC7148; GA MZd NC5900; GA ČR GA301/01/0985 Grant - others:GA CZ(CZ) Liga proti rakovině Institutional research plan: CEZ:AV0Z5052915 Keywords : MHC class I * IFN-gamma * HPV16 Subject RIV: FD - Oncology ; Hematology Impact factor: 0.527, year: 2003

  3. A Universal Rig for Supporting Large Hammer Drills: Reduced Injury Risk and Improved Productivity.

    Science.gov (United States)

    Rempel, David; Barr, Alan

    2015-10-01

    Drilling holes into concrete with heavy hammer and rock drills is one of the most physically demanding tasks performed in commercial construction and poses risks for musculoskeletal disorders, noise induced hearing loss, hand arm vibration syndrome and silicosis. The aim of this study was to (1) use a participatory process to develop a rig to support pneumatic rock drills or large electric hammer drills in order to reduce the health risks and (2) evaluate the usability of the rig. Seven prototype rigs for supporting large hammer drills were developed and modified with feedback from commercial contractors and construction workers. The final design was evaluated by laborers and electricians (N=29) who performed their usual concrete drilling with the usual method and the new rig. Subjective regional fatigue was significantly less in the neck, shoulders, hands and arms, and lower back) when using the universal rig compared to the usual manual method. Usability ratings for the rig were significantly better than the usual method on stability, control, drilling, accuracy, and vibration. Drilling time was reduced by approximately 50% with the rig. Commercial construction contractors, laborers and electricians who use large hammer drills for drilling many holes should consider using such a rig to prevent musculoskeletal disorders, fatigue, and silicosis.

  4. Systemic Activation of the IFN System by Exposure of Natural Epithelia to Physiologic (Low Dose) Levels of IFN

    Science.gov (United States)

    1990-06-20

    possibility that epithelial surfaces of the upper alimentary and/or respiratory mucosa exposed to lymphocytes treated with low concentrations of IFN or with IFN... Biotechnology Program Office of Naval Research Office of Naval Research 800 N. Quincy Street Code 1213 Arlington, VA 22217-5000 800 N. Quincy Street Arlington

  5. A Potent In Vivo Antitumor Efficacy of Novel Recombinant Type I Interferon.

    Science.gov (United States)

    Zhang, Kang-Jian; Yin, Xiao-Fei; Yang, Yuan-Qin; Li, Hui-Ling; Xu, Yan-Ni; Chen, Lie-Yang; Liu, Xi-Jun; Yuan, Su-Jing; Fang, Xian-Long; Xiao, Jing; Wu, Shuai; Xu, Hai-Neng; Chu, Liang; Katlinski, Kanstantsin V; Katlinskaya, Yuliya V; Guo, Rong-Bing; Wei, Guang-Wen; Wang, Da-Cheng; Liu, Xin-Yuan; Fuchs, Serge Y

    2017-04-15

    Purpose: Antiproliferative, antiviral, and immunomodulatory activities of endogenous type I IFNs (IFN1) prompt the design of recombinant IFN1 for therapeutic purposes. However, most of the designed IFNs exhibited suboptimal therapeutic efficacies against solid tumors. Here, we report evaluation of the in vitro and in vivo antitumorigenic activities of a novel recombinant IFN termed sIFN-I. Experimental Design: We compared primary and tertiary structures of sIFN-I with its parental human IFNα-2b, as well as affinities of these ligands for IFN1 receptor chains and pharmacokinetics. These IFN1 species were also compared for their ability to induce JAK-STAT signaling and expression of the IFN1-stimulated genes and to elicit antitumorigenic effects. Effects of sIFN-I on tumor angiogenesis and immune infiltration were also tested in transplanted and genetically engineered immunocompetent mouse models. Results: sIFN-I displayed greater affinity for IFNAR1 (over IFNAR2) chain of the IFN1 receptor and elicited a greater extent of IFN1 signaling and expression of IFN-inducible genes in human cells. Unlike IFNα-2b, sIFN-I induced JAK-STAT signaling in mouse cells and exhibited an extended half-life in mice. Treatment with sIFN-I inhibited intratumoral angiogenesis, increased CD8 + T-cell infiltration, and robustly suppressed growth of transplantable and genetically engineered tumors in immunodeficient and immunocompetent mice. Conclusions: These findings define sIFN-I as a novel recombinant IFN1 with potent preclinical antitumorigenic effects against solid tumor, thereby prompting the assessment of sIFN-I clinical efficacy in humans. Clin Cancer Res; 23(8); 2038-49. ©2016 AACR . ©2016 American Association for Cancer Research.

  6. The cytosolic exonuclease TREX1 inhibits the innate immune response to HIV-1

    Science.gov (United States)

    Yan, Nan; Regalado-Magdos, Ashton D.; Stiggelbout, Bart; Lee-Kirsch, Min Ae; Lieberman, Judy

    2010-01-01

    Viral infection triggers innate immune sensors to produce type I interferons (IFN). However, HIV infection of T cells and macrophages does not trip these alarms. How HIV avoids activating nucleic acid sensors is unknown. The cytosolic exonuclease TREX1 suppressed IFN triggered by HIV. In Trex1−/− mouse cells and human CD4+ T cells and macrophages in which TREX1 was inhibited by RNA interference, cytosolic HIV DNA accumulated, and HIV infection induced type I IFN that inhibited HIV replication and spreading. TREX1 bound to cytosolic HIV DNA and digested excess HIV DNA that would otherwise activate IFN expression via a TBK1, STING and IRF3 dependent pathway. HIV-stimulated IFN production in cells deficient in TREX1 did not involve known nucleic acid sensors. PMID:20871604

  7. Endurance test for IR rig for RI production assembly (test procedure)

    International Nuclear Information System (INIS)

    Chung, Heung June; Ryu, Jeong Soo

    2000-08-01

    This test procedure details the test loop, test method, and test procedure for pressure drop, vibration and endurance test of IR Rig for RI production. From the pressure drop test, the hydraulic design requirements of the capsule are verified. HANARO limit condition is checked and the compatibility with HANARO core is verified. From flow induced vibration test vibration frequency and displacement are investigated. The wear of IR Rig is investigated through endurance test, and these data are used to evaluate the expected wear at maximum resident time of the IR Rig for RI production

  8. IFN-γ and IP-10 in tracheal aspirates from premature infants: relationship with bronchopulmonary dysplasia.

    Science.gov (United States)

    Aghai, Zubair H; Saslow, Judy G; Mody, Kartik; Eydelman, Riva; Bhat, Vishwanath; Stahl, Gary; Pyon, Kee; Bhandari, Vineet

    2013-01-01

    Interferon-gamma (IFN-γ) and interferon-inducible protein of 10 kDa (IP-10) are potent inflammatory mediators and contribute to acute lung injury in adults. Recently, a potential role for IFN-γ and IP-10 in the pathogenesis of bronchopulmonary dysplasia (BPD) has been reported in animal models. To study the association between IFN-γ and IP-10 in tracheal aspirate (TA) and the development of BPD in premature infants. TA samples collected within 48 hr after birth from 79 mechanically ventilated premature neonates [gestational age (GA) IP-10 was determined using a commercially available ELISA kit. Total protein in TA was measured by Bradford assay to correct for sampling related dilution. BPD was defined as the need of supplemental oxygen at 36 weeks postmenstrual age (PMA). Twenty infants (GA 26.4 ± 1.9w, BW 860 ± 201 g) survived without BPD at 36 weeks PMA and 59 infants (GA 25.5 ± 1.5w, BW 751 ± 163 g) died before 36 weeks PMA or developed BPD. The mean IFN-γ level was higher in infants who died or developed BPD (9.7 ± 2.8 vs. 3.1 ± 1.1 pg/ml, P = 0.03). Similarly, the mean IP-10 level was higher in infants who died or developed BPD (63.4 ± 17.5 pg/ml) compared to those who survived without BPD (18.5 ± 7.5 pg/ml, P = 0.02). Higher IFN-γ and IP-10 levels in TA samples are associated with the development of BPD or death in premature infants. Copyright © 2012 Wiley Periodicals, Inc.

  9. IFN-Alpha receptor-1 upregulation in PBMC from HCV naïve patients carrying cc genotype. possible role of IFN-lambda.

    Directory of Open Access Journals (Sweden)

    Eleonora Lalle

    Full Text Available IL-28B gene polymorphisms predict better therapeutic response and spontaneous clearance of HCV. Moreover, higher expression of IFN-lambda has been reported in patients with the rs12979860 CC favourable genotype. The study aim was to establish possible relationships between IL-28B rs12979860 genotypes and expression of IFN-alpha receptor-1 (IFNAR-1 in naïve HCV patients, and to explore the possible role of IFN-lambda.IFNAR-1 mRNA levels were measured in PBMC from naïve patients with chronic hepatitis C with different IL-28 genotypes. The ability of IFN-lambda to up-regulate the expression of IFNAR-1 was established in PBMC from healthy donors carrying different IL-28B genotypes.Lower IFNAR-1 mRNA levels were observed in PBMC from HCV-infected naïve patients as compared to healthy donors. In healthy donors, IFNAR-1 mRNA levels were independent from IL-28B genotype, while in HCV patients, an increasing gradient was observed in TT vs CT vs CC carriers. In the latter group, a direct correlation between IFNAR-1 and endogenous IL-28B expression was observed. Moreover, IFN-lambda up-regulated IFNAR-1 expression in normal PBMC in a time-and dose-dependent manner, with a more effective response in CC vs TT carriers.Endogenous levels of IFN-lambda may be responsible for partial restoration of IFNAR-1 expression in HCV patients with favourable IL-28 genotype. This, in turn, may confer to CC carriers a response advantage to either endogenous or exogenous IFN-alpha, representing the biological basis for the observed association between CC genotype and favourable outcome of either natural infection (clearance vs chronicization or IFN therapy.

  10. The Phase-I Trigger Readout Electronics Upgrade of the ATLAS Liquid Argon Calorimeters

    CERN Document Server

    Yang, Yi-lin; The ATLAS collaboration

    2018-01-01

    The Super Cell has been proposed in the Phase-I LAr upgrade to replace the existing trigger system "Trigger Tower" due to higher luminosity environments in Run 3 at LHC. The higher granularity of the Super Cell trigger systems requires higher data transmission and processing rate. The new system is also needed to be compatible with the existing trigger system. To fulfill these requirements, the new electronics including frond end and back end are developed. In the front-end part, the new LSB sums the LAr cell signals into Super Cell signals. The new baseplane distributes analog signals among FEBs, LTDB and TBB. The LTDB sums Super Cell signals to Trigger Tower signals and redirected the signals to TBB. The Analog signals are also digitized in LTDB and then sent to back end electronics. In the back-end part, the architecture is based on ATCA. The LAr carrier is used for monitoring and controlling. The LATOMEs inserted into the LAr carrier provide energy calculation from the digitized signals. So far, the demon...

  11. Development and Validation of a Novel Dual Luciferase Reporter Gene Assay to Quantify Ebola Virus VP24 Inhibition of IFN Signaling

    Directory of Open Access Journals (Sweden)

    Elisa Fanunza

    2018-02-01

    Full Text Available The interferon (IFN system is the first line of defense against viral infections. Evasion of IFN signaling by Ebola viral protein 24 (VP24 is a critical event in the pathogenesis of the infection and, hence, VP24 is a potential target for drug development. Since no drugs target VP24, the identification of molecules able to inhibit VP24, restoring and possibly enhancing the IFN response, is a goal of concern. Accordingly, we developed a dual signal firefly and Renilla luciferase cell-based drug screening assay able to quantify IFN-mediated induction of Interferon Stimulated Genes (ISGs and its inhibition by VP24. Human Embryonic Kidney 293T (HEK293T cells were transiently transfected with a luciferase reporter gene construct driven by the promoter of ISGs, Interferon-Stimulated Response Element (ISRE. Stimulation of cells with IFN-α activated the IFN cascade leading to the expression of ISRE. Cotransfection of cells with a plasmid expressing VP24 cloned from a virus isolated during the last 2014 outbreak led to the inhibition of ISRE transcription, quantified by a luminescent signal. To adapt this system to test a large number of compounds, we performed it in 96-well plates; optimized the assay analyzing different parameters; and validated the system by calculating the Z′- and Z-factor, which showed values of 0.62 and 0.53 for IFN-α stimulation assay and VP24 inhibition assay, respectively, indicative of robust assay performance.

  12. The economics and related factors involved in the replacement of land drilling rigs

    International Nuclear Information System (INIS)

    Holm, D.W.

    1992-01-01

    The principal purpose of this paper is to evaluate the construction cost of a medium depth land rig made from all NEW components and the resulting effect on drilling contractor economics. This evaluation will include an inventory of the proposed NEW rig, with a comparison of the costs of a similar rig built in 1981-1982, and a similar rig built from existing UNUSED equipment in manufacturer's current inventory. The paper discusses the problems encountered in obtaining quotations for NEW equipment from manufacturers, the current attitudes of equipment manufacturers, the potential for problems from the use of existing UNUSED equipment in manufacturers inventory, and finally the possible effect on the day rates needed to justify the construction of NEW land rigs. Probable reasons for the attitudes of the manufacturing industry and alternatives for the drilling contractor will be reviewed

  13. A power recirculating test rig for ball screw endurance tests

    Directory of Open Access Journals (Sweden)

    Giberti Hermes

    2016-01-01

    Full Text Available A conceptual design of an innovative test rig for endurance tests of ball screws is presented in this paper. The test rig layout is based on the power recirculating principle and it also allows to overtake the main critical issues of the ball screw endurance tests. Among these there are the high power required to make the test, the lengthy duration of the same and the high loads between the screw and the frame that holds it. The article describes the test rig designed scheme, the kinematic expedients to be adopted in order to obtain the required performance and functionality and the sizing procedure to choose the actuation system.

  14. Human Cytomegalovirus Encoded miR-US25-1-5p Attenuates CD147/EMMPRIN-Mediated Early Antiviral Response

    Directory of Open Access Journals (Sweden)

    Jun Chen

    2017-12-01

    Full Text Available Cellular receptor-mediated signaling pathways play critical roles during the initial immune response to Human Cytomegalovirus (HCMV infection. However, the involvement of type-I transmembrane glycoprotein CD147/EMMPRIN (extracellular matrix metalloproteinase inducer in the antiviral response to HCMV infection is still unknown. Here, we demonstrated the specific knockdown of CD147 significantly decreased HCMV-induced activation of NF-κB and Interferon-beta (IFN-β, which contribute to the cellular antiviral responses. Next, we confirmed that HCMV-encoded miR-US25-1-5p could target the 3′ UTR (Untranslated Region of CD147 mRNA, and thus facilitate HCMV lytic propagation at a low multiplicity of infection (MOI. The expression and secretion of Cyclophilin A (sCyPA, as a ligand for CD147 and a proinflammatory cytokine, were up-regulated in response to HCMV stimuli. Finally, we confirmed that CD147 mediated HCMV-triggered antiviral signaling via the sCyPA-CD147-ERK (extracellular regulated protein kinases/NF-κB axis signaling pathway. These findings reveal an important HCMV mechanism for evading antiviral innate immunity through its encoded microRNA by targeting transmembrane glycoprotein CD147, and a potential cause of HCMV inflammatory disorders due to the secretion of proinflammatory cytokine CyPA.

  15. Pig but not Human Interferon-γ Initiates Human Cell-Mediated Rejection of Pig Tissue in vivo

    Science.gov (United States)

    Sultan, Parvez; Murray, Allan G.; McNiff, Jennifer M.; Lorber, Marc I.; Askenase, Philip W.; Bothwell, Alfred L. M.; Pober, Jordan S.

    1997-08-01

    Split-thickness pig skin was transplanted on severe combined immunodeficient mice so that pig dermal microvessels spontaneously inosculated with mouse microvessels and functioned to perfuse the grafts. Pig endothelial cells in the healed grafts constitutively expressed class I and class II major histocompatibility complex molecules. Major histocompatibility complex molecule expression could be further increased by intradermal injection of pig interferon-γ (IFN-γ ) but not human IFN-γ or tumor necrosis factor. Grafts injected with pig IFN-γ also developed a sparse infiltrate of mouse neutrophils and eosinophils without evidence of injury. Introduction of human peripheral blood mononuclear cells into the animals by intraperitoneal inoculation resulted in sparse perivascular mononuclear cell infiltrates in the grafts confined to the pig dermis. Injection of pig skin grafts on mice that received human peripheral blood mononuclear cells with pig IFN-γ (but not human IFN-γ or heat-inactivated pig IFN-γ ) induced human CD4+ and CD8+ T cells and macrophages to more extensively infiltrate the pig skin grafts and injure pig dermal microvessels. These findings suggest that human T cell-mediated rejection of xenotransplanted pig organs may be prevented if cellular sources of pig interferon (e.g., passenger lymphocytes) are eliminated from the graft.

  16. Saving money on rig refurbishments through foreign trade zones or duty-drawback

    International Nuclear Information System (INIS)

    Ward, R.J. Jr.

    1997-01-01

    The recent boom in day rates for rigs capable of drilling in deep water and harsh environments has created a frenzy of rig refurbishment activity in shipyards located in US Gulf states. In most instances, the destination for the rigs upon completion is the US Outer Continental Shelf (USOCS) in the Gulf of Mexico. The problem faced by contractors/operators planning to use US shipyards is that this circumstance has caused difficulty in shielding rigs and their foreign-sourced components from US Customs duties. Under US Customs law, a bona fide exportation requires severance from US commerce and joining to the commerce of some foreign country or, in the case of a vessel supply, a qualifying international voyage. The USOCS does not qualify as an exportation, nor do movements to drilling sites located on it qualify as an international voyage. Described here are two possible solutions to this economic dilemma and an example of how the foreign trade zone solution was applied by Global marine in its plans for upgrading some of its semisubmersible drilling rigs for deepwater USOCS work

  17. RNase L mediated protection from virus induced demyelination.

    Directory of Open Access Journals (Sweden)

    Derek D C Ireland

    2009-10-01

    Full Text Available IFN-alpha/beta plays a critical role in limiting viral spread, restricting viral tropism and protecting mice from neurotropic coronavirus infection. However, the IFN-alpha/beta dependent mechanisms underlying innate anti-viral functions within the CNS are poorly understood. The role of RNase L in viral encephalomyelitis was explored based on its functions in inhibiting translation, inducing apoptosis, and propagating the IFN-alpha/beta pathway through RNA degradation intermediates. Infection of RNase L deficient (RL(-/- mice with a sub-lethal, demyelinating mouse hepatitis virus variant revealed that the majority of mice succumbed to infection by day 12 p.i. However, RNase L deficiency did not affect overall control of infectious virus, or diminish IFN-alpha/beta expression in the CNS. Furthermore, increased morbidity and mortality could not be attributed to altered proinflammatory signals or composition of cells infiltrating the CNS. The unique phenotype of infected RL(-/- mice was rather manifested in earlier onset and increased severity of demyelination and axonal damage in brain stem and spinal cord without evidence for enhanced neuronal infection. Increased tissue damage coincided with sustained brain stem infection, foci of microglia infection in grey matter, and increased apoptotic cells. These data demonstrate a novel protective role for RNase L in viral induced CNS encephalomyelitis, which is not reflected in overall viral control or propagation of IFN-alpha/beta mediated signals. Protective function is rather associated with cell type specific and regional restriction of viral replication in grey matter and ameliorated neurodegeneration and demyelination.

  18. TITAN - a 9 MW, 179 bar pressurised water rig

    International Nuclear Information System (INIS)

    Mogford, D.J.; Lee, D.H.

    1987-02-01

    The report describes the TITAN rig built at Winfrith for thermal hydraulic experiments with water at up to 179 bar pressure. A power supply of 9 MW is available. The report describes three typical experiments that show the versatility of the rig. The first is a 25 rod pressurized water reactor fuel bundle critical heat flux experiment, the second is a parallel channel evaporator test and the third is a model jet pump test. (author)

  19. cGAMP Quantification in Virus-Infected Human Monocyte-Derived Cells by HPLC-Coupled Tandem Mass Spectrometry.

    Science.gov (United States)

    Paijo, Jennifer; Kaever, Volkhard; Kalinke, Ulrich

    2017-01-01

    Upon virus infection, cells of the innate immune system such as dendritic cells and macrophages can mount type I interferon (IFN-I) responses that restrict viral dissemination. To inform host cells of virus infection, detection of cytosolic DNA is one important mechanism. Inappropriate sensing of endogenous DNA and subsequent induction of IFN-I responses can also cause autoimmunity, highlighting the need to tightly regulate DNA sensing. The cyclic GMP-AMP synthase (cGAS) was recently identified to be the major sensor of cytosolic DNA that triggers IFN-I expression. Upon DNA binding, cGAS synthesizes the second messenger cyclic guanosine-adenosine monophosphate (cGAMP) that induces IFN-I expression by the activation of the stimulator of interferon genes (STING). Notably, cGAMP does not only act in infected cells, but can also be relocated to noninfected bystander cells to there trigger IFN-I expression. Thus, direct quantification of cGAMP in cells of the innate immune system is an important approach to study where, when, and how DNA is sensed and IFN-I responses are induced. Here, we describe a method that allows specific quantification of cGAMP from extracts of virus-infected human myeloid cells by HPLC-coupled tandem mass spectrometry.

  20. Interferons and interferon (IFN)-inducible protein 10 during highly active anti-retroviral therapy (HAART)-possible immunosuppressive role of IFN-alpha in HIV infection

    DEFF Research Database (Denmark)

    Stylianou, E; Aukrust, P; Bendtzen, K

    2000-01-01

    -infected patients had raised levels of both IP-10 and IFN-alpha compared with healthy controls (n = 19), with particularly high levels in advanced disease. HAART induced a marked decrease in levels of both IFN-alpha, neopterin and IP-10, though not to normal concentrations. In contrast, IFN-gamma levels were low...

  1. Speeding up : new Atlas Copco rig meant to cut non-drilling time

    Energy Technology Data Exchange (ETDEWEB)

    Roche, P.

    2009-06-15

    Automation has significantly reduced the time needed to drill shallow to medium-depth wells. The time it takes for a drill to reach the production zone is decreasing because newly developed hydraulic systems are able to maintain a constant pace. However, a great deal of time is still consumed by demobilization, transportation and setting up to drill the next well. Atlas Copco Drilling Solutions, a Swedish-based global maker of industrial equipment such as mining and mineral exploration rigs, designed a new Predator drilling system that consists of a mobile rig, a substructure and a pipe-handling skate. The Predator drilling system reduces non-drilling time and the associated costs. This article described the design of this new drilling system with particular reference to how it combines the mobile rig, the substructure and the pipe-handling skate into a three-load package. In order to reduce rig weight and improve mobility, the system is designed so that the table, master bushing, hydraulic slips and iron roughneck are part of the substructure that travel together. The rig has a working hook load capacity of 200,000 pounds, translating into a nominal depth capacity of 8,000 to 10,000 feet. The article also described the mounting of the rig, maneuverability, hydraulic control, and pipe-handling safety. Its various components were also described. 1 ref., 1 fig.

  2. Robotics Test Rig

    International Nuclear Information System (INIS)

    Schuurmans, P.

    2007-01-01

    The experimental Accelerator Driven System XT-ADS is being developed within the European 6th framework programme EUROTRANS using the MYRRHA DRAFT-2 as starting point. The aim for the XT-ADS is to demonstrate the feasibility of the ADS concept at reasonable power levels and to serve as a high performance, multi-purpose experimental irradiation device. One of the fundamental design options that has been taken is to do all maintenance and in-service inspection and repair duties by remote handling. Outside the XT-ADS vessel in a controlled though radio-active environment, remote handling concepts as those already in use at e.g. the Joint European Torus (JET) can be used. Extrapolation to remote handling inside the lead-bismuth eutectic filled main vessel of the XT-ADS is in principle feasible as was shown in a 2003 study performed by Oxford Technologies ltd for the case of MYRRHA. Nevertheless, it is clear that all critical remote handling components need to be qualified for use in liquid LBE. Thus, as a first step, a proof of principle (POP) experimental test rig is require. The principal goal of this work is to identify the critical technological issues that must be resolved to allow operation of remote handling manipulators inside the LBE filled main vessel of the XT-ADS and to propose a concept design and specification catalogue for a proof of principle test rig that is able to experimentally verify the main aspects of manipulator design

  3. HCV-specific immune responses induced by CIGB-230 in combination with IFN-α plus ribavirin

    Science.gov (United States)

    Amador-Cañizares, Yalena; Martínez-Donato, Gillian; Álvarez-Lajonchere, Liz; Vasallo, Claudia; Dausá, Mariacarla; Aguilar-Noriega, Daylen; Valenzuela, Carmen; Raíces, Ivette; Dubuisson, Jean; Wychowski, Czeslaw; Cinza-Estévez, Zurina; Castellanos, Marlén; Núñez, Magdalys; Armas, Anny; González, Yaimé; Revé, Ismariley; Guerra, Ivis; Pérez Aguiar, Ángel; Dueñas-Carrera, Santiago

    2014-01-01

    AIM: To analyze hepatitis C virus (HCV)-specific immune responses in chronically infected patients under triple therapy with interferon-α (IFN-α) plus ribavirin and CIGB-230. METHODS: CIGB-230 was administered in different schedules with respect to IFN-α plus ribavirin therapy. Paired serum and peripheral blood mononuclear cells (PBMC) samples from baseline and end of treatment were analyzed. The HCV-specific humoral response was tested by enzyme-linked immunosorbent assay, neutralizing antibodies were evaluated by cell culture HCV neutralization assays, PBMC proliferation was assayed by carboxyfluorescein succinimidyl ester staining and IFN-γ secretion was assessed by enzyme-linked immunospot. Data on virological and histological response and their association with immune variables are also provided. RESULTS: From week 12 to week 48, all groups of patients showed a significant reduction in mean leukocyte counts. Statistically significant reductions in antibody titers were frequent, but only individuals immunized with CIGB-230 as early add-on treatment sustained the core-IgG response, and the neutralizing antibody response was enhanced only in patients receiving CIGB-230. Cell-mediated immune responses also tended to decline, but significant reductions in IFN-γ secretion and total absence of core-specific lymphoproliferation were exclusive of the control group. Only CIGB-230-immunized individuals showed de novo induced lymphoproliferative responses against the structural antigens. Importantly, it was demonstrated that the quality of the CIGB-230-induced immune response depended on the number of doses and timing of administration in relation to the antiviral therapy. Specifically, the administration of 6 doses of CIGB-230 as late add-on to therapy increased the neutralizing antibody activity and the de novo core-specific IFN-γ secretion, both of which were associated with the sustained virological response. CONCLUSION: CIGB-230, combined with IFN

  4. Testing of elastomer seals using small-size rigs

    International Nuclear Information System (INIS)

    Leeks, C.W.E.; Dunford, B.; Barnfield, J.H.; Gray, I.L.S.

    1997-01-01

    This paper looks at the use of small size seal leakage test rigs to demonstrate the compliance of full size container seals against the IAEA Transport Regulation's limits for activity release for normal transport and accident conditions. The detailed requirements of the regulations are discussed and it is concluded that an appropriate test programme to meet these requirements using only small size test rigs, can normally be set up and carried out on a relatively short time scale. It is important that any small test rigs should be designed to represent the relevant features of the seal arrangement and the overall test programme should cover all of the conditions, specified by the regulations, for the type, classification and contents of the container under consideration. The parameters of elastomer O-rings, which affect their sealing ability, are considered and those which are amenable to small scale testing or have to be modelled at full size are identified. Generally, the seals used in leakage tests have to be modelled with a full size cross-section but can have a reduced peripheral length. (Author)

  5. Dendritic Cell Stimulation by IFN-β Alters T Cell Function via Modulation of Cytokine Secretion in Diabetes Type 1

    Directory of Open Access Journals (Sweden)

    Abediankenari Saeid

    2009-10-01

    Full Text Available During antigen capture and processing, mature dendritic cells (DC express large amounts of peptide-MHC complexes and accessory molecules on their surface. We investigated the role of IFN-β in induction HLA-G expression on the monocyte derived DC and cytokine profile in diabetes type 1. We accomplished secretary pattern and total cytokine production of the Th1 cytokine (IL-2, γIFN and Th2 cytokines (IL-4, IL-10 before and after mixed leukocyte reaction (MLR of 30 diabetic patients and 30 normal subjects.   In this study a significant increase of IL-10 and γIFN reduction after IFN-β Therapy in culture in presence of HLA-G bearing DC as compared to control were seen. It is seen that dendritic cell causes IL-10 production of T cell in vitro that reduce T cell activation from diabetes patients and normal subjects resulted to the production and expression of HLA-G on these cells from both groups. Using mixed leukocyte reaction, it was found that IFN-β-treated dendritic cell mediated the inhibition of autologous T cell activation via IL-10 production and level of HLA-G on dendritic cell may be correlated to disease activity in diabetes patients and it could also serve as a useful marker for disease progress and treatment.

  6. Automatic X-ray television rig for high-speed radiography of polycrystals

    International Nuclear Information System (INIS)

    Bezbakh, V.D.; Garasim, Yu.A.; Oshkaderov, S.P.; Pet'kov, V.V.

    1993-01-01

    The high-speed radiography method is used for studying the phase and structural transformation in metals and alloys during rapid changes in temperature. In order to improve the effectiveness of this method the Institute of Metal Physics, Ukrainian Academy of Sciences, has developed an automatic rig for high-speed radiography of polycrystalline materials using a television method for recording the x-ray diffraction patterns. The rig, described here, consists of an x-ray block, a vacuum chamber, a device for programmed electro-contact heating of specimens, a system for imaging and scanning x-ray diffraction patterns, and a system for collecting and analyzing the data. Focusing is carried out by the Zeeman-Bolin method. The new rig helps to significantly reduce the recording time and ensures adequate quality and reliability of the recorded diffraction image over a wide range of temperatures. Data using the rig is presented for high-speed radiography for cooling a specimen of G20 steel. 4 refs., 4 figs

  7. Ester alkaloids from Cephalotaxus interfere with the 2'3'-cGAMP-induced type I interferon pathway in vitro.

    Directory of Open Access Journals (Sweden)

    Gayoung Park

    Full Text Available Dysregulated activation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING pathway by self-DNA contributes to interferonopathy and promotes autoimmune diseases. To identify potential suppressors of STING-induced type I interferon (IFN induction, ethanol extracts of medicinal plants were screened for inhibitory activity against IFN-ß promoter activation. Notably, 70% ethanol extract of Cephalotaxus koreana specifically down-regulated STING-induced, but not TBK1- or IRF3-induced, IFN-ß promoter activity. The compounds exerting inhibitory activity specifically against STING-mediated IFN-ß promoter activation were identified as ester alkaloids isolated from the genus, Cephalotaxus, homoharringtonine and harringtonine. Furthermore, these two compounds inhibited 2'3'-cGAMP-induced IFN-stimulated gene expression and interaction between STING and TBK1. These suppressive effects were not observed with cephalotaxine devoid of the ester side-chain. Our data support the potential utility of homoharringtonine and harringtonine to treat STING-associated interferonopathy and autoimmune diseases.

  8. Experimental Analysis of Mast Lifting and Bending Forces on Vibration Patterns Before and After Pinion Reinstallation in an OH-58 Transmission Test Rig

    Science.gov (United States)

    Huff, Edward M.; Lewicki, David G.; Tumer, Irem Y.; Decker, Harry; Barszez, Eric; Zakrajsek, James J.; Norvig, Peter (Technical Monitor)

    2000-01-01

    As part of a collaborative research program between NASA Ames Research Center (ARC), NASA Glenn Research Center (GRC), and the US Army Laboratory, a series of experiments is being performed in GRC's 500 HP OH-58 Transmission Test Rig facility and ARC's AH-I Cobra and OH-58c helicopters. The findings reported in this paper were drawn from Phase-I of a two-phase test-rig experiment, and are focused on the vibration response of an undamaged pinion gear operating in the transmission test rig. To simulate actual flight conditions, the transmission system was run at three torque levels, as well as two mast lifting and two mast bending levels. The test rig was also subjected to disassembly and reassembly of the main pinion housing to simulate the effect of maintenance operations. An analysis of variance based on the total power of the spectral distribution indicates the relative effect of each experimental factor, including Wong interactions with torque. Reinstallation of the main pinion assembly is shown to introduce changes in the vibration signature, suggesting the possibility of a strong effect of maintenance on HUMS design and use. Based on these results, further research will be conducted to compare these vibration responses with actual OH58c helicopter transmission vibration patterns.

  9. Cutting edge: Antimalarial drugs inhibit IFN-β production through blockade of cyclic GMP-AMP synthase-DNA interaction.

    Science.gov (United States)

    An, Jie; Woodward, Joshua J; Sasaki, Tomikazu; Minie, Mark; Elkon, Keith B

    2015-05-01

    Type I IFN is strongly implicated in the pathogenesis of systemic autoimmune diseases, such as lupus, and rare monogenic IFNopathies, including Aicardi-Goutières syndrome. Recently, a new DNA-activated pathway involving the enzyme cyclic GMP-AMP synthase (cGAS) was described and potentially linked to Aicardi-Goutières syndrome. To identify drugs that could potentially inhibit cGAS activity, we performed in silico screening of drug libraries. By computational analysis, we identified several antimalarial drugs (AMDs) that were predicted to interact with the cGAS/dsDNA complex. Our studies validated that several AMDs were effective inhibitors of IFN-β production and that they functioned by inhibiting dsDNA stimulation of cGAS. Because AMDs have been widely used in human diseases and have an excellent safety profile, our findings suggest new therapeutic strategies for the treatment of severe debilitating diseases associated with type I IFNs due to cGAS activation. Copyright © 2015 by The American Association of Immunologists, Inc.

  10. Comprehensive Antiretroviral Restriction Factor Profiling Reveals the Evolutionary Imprint of the ex Vivo and in Vivo IFN-β Response in HTLV-1-Associated Neuroinflammation.

    Science.gov (United States)

    Leal, Fabio E; Menezes, Soraya Maria; Costa, Emanuela A S; Brailey, Phillip M; Gama, Lucio; Segurado, Aluisio C; Kallas, Esper G; Nixon, Douglas F; Dierckx, Tim; Khouri, Ricardo; Vercauteren, Jurgen; Galvão-Castro, Bernardo; Saraiva Raposo, Rui Andre; Van Weyenbergh, Johan

    2018-01-01

    HTLV-1-Associated Myelopathy (HAM/TSP) is a progressive neuroinflammatory disorder for which no disease-modifying treatment exists. Modest clinical benefit from type I interferons (IFN-α/β) in HAM/TSP contrasts with its recently identified IFN-inducible gene signature. In addition, IFN-α treatment in vivo decreases proviral load and immune activation in HAM/TSP, whereas IFN-β therapy decreases tax mRNA and lymphoproliferation. We hypothesize this "IFN paradox" in HAM/TSP might be explained by both cell type- and gene-specific effects of type I IFN in HTLV-1-associated pathogenesis. Therefore, we analyzed ex vivo transcriptomes of CD4 + T cells, PBMCs and whole blood in healthy controls, HTLV-1-infected individuals, and HAM/TSP patients. First, we used a targeted approach, simultaneously quantifying HTLV-1 mRNA (HBZ, Tax), proviral load and 42 host genes with known antiretroviral (anti-HIV) activity in purified CD4 + T cells. This revealed two major clusters ("antiviral/protective" vs. "proviral/deleterious"), as evidenced by significant negative (TRIM5/TRIM22/BST2) vs. positive correlation (ISG15/PAF1/CDKN1A) with HTLV-1 viral markers and clinical status. Surprisingly, we found a significant inversion of antiretroviral activity of host restriction factors, as evidenced by opposite correlation to in vivo HIV-1 vs. HTLV-1 RNA levels. The anti-HTLV-1 effect of antiviral cluster genes was significantly correlated to their adaptive chimp/human evolution score, for both Tax mRNA and PVL. Six genes of the proposed antiviral cluster underwent lentivirus-driven purifying selection during primate evolution (TRIM5/TRIM22/BST2/APOBEC3F-G-H), underscoring the cross-retroviral evolutionary imprint. Secondly, we examined the genome-wide type I IFN response in HAM/TSP patients, following short-term ex vivo culture of PBMCs with either IFN-α or IFN-β. Microarray analysis evidenced 12 antiretroviral genes (including TRIM5α/TRIM22/BST2) were significantly up-regulated by IFN

  11. PNNL Hoisting and Rigging Manual

    Energy Technology Data Exchange (ETDEWEB)

    Haynie, Todd O.; Fullmer, Michael W.

    2008-12-29

    This manual describes the safe and cost effective operation, inspection, maintenance, and repair requirements for cranes, hoists, fork trucks, slings, rigging hardware, and hoisting equipment. It is intended to be a user's guide to requirements, codes, laws, regulations, standards, and practices that apply to Pacific Northwest National Laboratory (PNNL) and its subcontractors.

  12. A Dynamic Behavior of the Nuclear Test Rig with Coolant using the Fluid-Structural interaction Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tae-Ho; Hong, Jintae; Ahn, Sung-Ho; Joung, Chang-Young; Jang, Seo-Yun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yeon, Kon-Whi [Chungnam National University, Daejeon (Korea, Republic of)

    2016-10-15

    In this paper, the dynamic behavior of the test rig in the coolant flow simulator is evaluated by using the 2-way fluid-structural interaction analysis. The maximum value and location of the deformation and equivalent stress in the test rig is confirmed. The fluid-structural interaction analysis is applied to perform the fluid and structural analysis A fluid-structure interaction analysis is used to simulate the relationship between the deformation and hydraulic pressure. There are two types of fluid-structural interaction analysis. One is a 1-way direction analysis in which the hydraulic pressure is calculated by a CFD and transmitted to the surface of the structure, and a structural analysis is then performed. The other is a 2-way direction analysis that is performed by changing the data between the deformation of the structural and pressure of the coolant water for every time step. The location of the maximum deformation of the test rig is the bottom parts of the test rig. It is expected that the equivalent stress of the test rig is occurred. The maximum equivalent stress in the test rig under the circulation of the coolant is 90.1 MPa. The location of the maximum stress in the test rig is the connect part between the fuel rod and flow divider. A safety factor on the test rig is 3, approximately. The deformation motion of the test rig at the bottom part of the test rig is caused about the fluid-induced vibration. A test on the fluid-induced vibration of the test rig will be performed and compared with results of the analysis in further paper.

  13. Constitutively Active MAVS Inhibits HIV-1 Replication via Type I Interferon Secretion and Induction of HIV-1 Restriction Factors.

    Directory of Open Access Journals (Sweden)

    Sachin Gupta

    Full Text Available Type I interferon is known to inhibit HIV-1 replication through the induction of interferon stimulated genes (ISG, including a number of HIV-1 restriction factors. To better understand interferon-mediated HIV-1 restriction, we constructed a constitutively active form of the RIG-I adapter protein MAVS. Constitutive MAVS was generated by fusion of full length MAVS to a truncated form of the Epstein Barr virus protein LMP1 (ΔLMP1. Supernatant from ΔLMP1-MAVS-transfected 293T cells contained high levels of type I interferons and inhibited HIV replication in both TZM-bl and primary human CD4+ T cells. Supernatant from ΔLMP1-MAVS-transfected 293T cells also inhibited replication of VSV-G pseudotyped single cycle SIV in TZM-bl cells, suggesting restriction was post-entry and common to both HIV and SIV. Gene array analysis of ΔLMP1-MAVS-transfected 293T cells and trans-activated CD4+ T cells showed significant upregulation of ISG, including previously characterized HIV restriction factors Viperin, Tetherin, MxB, and ISG56. Interferon blockade studies implicated interferon-beta in this response. In addition to direct viral inhibition, ΔLMP1-MAVS markedly enhanced secretion of IFN-β and IL-12p70 by dendritic cells and the activation and maturation of dendritic cells. Based on this immunostimulatory activity, an adenoviral vector (Ad5 expressing ΔLMP1-MAVS was tested as a molecular adjuvant in an HIV vaccine mouse model. Ad5-Gag antigen combined with Ad5-ΔLMP1-MAVS enhanced control of vaccinia-gag replication in a mouse challenge model, with 4/5 animals showing undetectable virus following challenge. Overall, ΔLMP1-MAVS is a promising reagent to inhibit HIV-1 replication in infected tissues and enhance vaccine-mediated immune responses, while avoiding toxicity associated with systemic type I interferon administration.

  14. A crucial role for plasmacytoid dendritic cells in antiviral protection by CpG ODN–based vaginal microbicide

    Science.gov (United States)

    Shen, Hong; Iwasaki, Akiko

    2006-01-01

    Topical microbicides represent a promising new approach to preventing HIV and other sexually transmitted infections. TLR agonists are ideal candidates for microbicides, as they trigger a multitude of antiviral genes effective against a broad range of viruses. Although vaginal application of CpG oligodeoxynucleotides (ODNs) and poly I:C has been shown to protect mice from genital herpes infection, the mechanism by which these agents provide protection remains unclear. Here, we show that plasmacytoid DCs (pDCs) are required for CpG ODN–mediated protection against lethal vaginal challenge with herpes simplex virus type 2 (HSV-2). Moreover, we demonstrate that cells of both the hematopoietic and stromal compartments must respond to CpG ODN via TLR9 and to type I IFNs through IFN-αβ receptor (IFN-αβR) for protection. Thus, crosstalk between pDCs and vaginal stromal cells provides for optimal microbicide efficacy. Our results imply that temporally and spatially controlled targeting of CpG ODN to pDCs and epithelial cells can potentially maximize their effectiveness as microbicides while minimizing the associated inflammatory responses. PMID:16878177

  15. Technical and economic evaluation of selected compact drill rigs for drilling 10,000 foot geothermal production wells

    Energy Technology Data Exchange (ETDEWEB)

    Huttrer, G.W. [Geothermal Management Company, Inc., Frisco, CO (United States)

    1997-11-01

    This report summarizes the investigation and evaluation of several {open_quotes}compact{close_quotes} drill rigs which could be used for drilling geothermal production wells. Use of these smaller rigs would save money by reducing mobilization costs, fuel consumption, crew sizes, and environmental impact. Advantages and disadvantages of currently-manufactured rigs are identified, and desirable characteristics for the {open_quotes}ideal{close_quotes} compact rig are defined. The report includes a detailed cost estimate of a specific rig, and an evaluation of the cost/benefit ratio of using this rig. Industry contacts for further information are given.

  16. Influenza A virus does not encode a tetherin antagonist with Vpu-like activity and induces IFN-dependent tetherin expression in infected cells.

    Directory of Open Access Journals (Sweden)

    Michael Winkler

    Full Text Available The interferon-induced host cell factor tetherin inhibits release of human immunodeficiency virus (HIV from the plasma membrane of infected cells and is counteracted by the HIV-1 protein Vpu. Influenza A virus (FLUAV also buds from the plasma membrane and is not inhibited by tetherin. Here, we investigated if FLUAV encodes a functional equivalent of Vpu for tetherin antagonism. We found that expression of the FLUAV protein NS1, which antagonizes the interferon (IFN response, did not block the tetherin-mediated restriction of HIV release, which was rescued by Vpu. Similarly, tetherin-mediated inhibition of HIV release was not rescued by FLUAV infection. In contrast, FLUAV infection induced tetherin expression on target cells in an IFN-dependent manner. These results suggest that FLUAV escapes the antiviral effects of tetherin without encoding a tetherin antagonist with Vpu-like activity.

  17. BURNER RIG TESTING OF A500 C/SiC

    Science.gov (United States)

    2018-03-17

    AFRL-RX-WP-TR-2018-0071 BURNER RIG TESTING OF A500® C /SiC Larry P. Zawada Universal Technology Corporation Jennifer Pierce UDRI...TITLE AND SUBTITLE BURNER RIG TESTING OF A500® C /SiC 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62102F 6...test program characterized the durability behavior of A500® C /SiC ceramic matrix composite material at room and elevated temperature. Specimens were

  18. Design and Checkout of a High Speed Research Nozzle Evaluation Rig

    Science.gov (United States)

    Castner, Raymond S.; Wolter, John D.

    1997-01-01

    The High Flow Jet Exit Rig (HFJER) was designed to provide simulated mixed flow turbojet engine exhaust for one- seventh scale models of advanced High Speed Research test nozzles. The new rig was designed to be used at NASA Lewis Research Center in the Nozzle Acoustic Test Rig and the 8x6 Supersonic Wind Tunnel. Capabilities were also designed to collect nozzle thrust measurement, aerodynamic measurements, and acoustic measurements when installed at the Nozzle Acoustic Test Rig. Simulated engine exhaust can be supplied from a high pressure air source at 33 pounds of air per second at 530 degrees Rankine and nozzle pressure ratios of 4.0. In addition, a combustion unit was designed from a J-58 aircraft engine burner to provide 20 pounds of air per second at 2000 degrees Rankine, also at nozzle pressure ratios of 4.0. These airflow capacities were designed to test High Speed Research nozzles with exhaust areas from eighteen square inches to twenty-two square inches. Nozzle inlet flow measurement is available through pressure and temperature sensors installed in the rig. Research instrumentation on High Speed Research nozzles is available with a maximum of 200 individual pressure and 100 individual temperature measurements. Checkout testing was performed in May 1997 with a 22 square inch ASME long radius flow nozzle. Checkout test results will be summarized and compared to the stated design goals.

  19. Involvement of activation of PKR in HBx-siRNA-mediated innate immune effects on HBV inhibition.

    Directory of Open Access Journals (Sweden)

    Qiuju Han

    Full Text Available RNA interference (RNAi of virus-specific genes offers the possibility of developing a new anti-hepatitis B virus (anti-HBV therapy. Recent studies have revealed that siRNAs can induce an innate immune response in vitro and in vivo. Here, HBVx (HBx mRNA expression and HBV replication were significantly inhibited, followed by the enhancement of expression of type I interferons (IFNs, IFN-stimulated genes (ISG15 and ISG56 and proinflammatory cytokines after HepG2.2.15 cells were transfected with chemically synthesized HBx-siRNAs. Transfection with HBx-siRNAs also significantly increased expression of dsRNA-dependent protein kinase R (PKR in HepG2.2.15 cells, followed by activation of downstream signaling events such as eukaryotic initiation factor 2α (eIF2-α. In PKR-over-expressing HepG2.2.15 cells, HBx-siRNAs exerted more potent inhibitory effects on HBV replication and greater production of type I IFNs. By contrast, the inhibitory effect of HBx-siRNAs on HBV replication was attenuated when PKR was inhibited or silenced, demonstrating that HBx-siRNAs greatly promoted PKR activation, leading to the higher production of type I IFN. Therefore, we concluded that PKR is involved in the innate immune effects mediated by HBx-siRNAs and further contributes to HBV inhibition. The bifunctional siRNAs with both gene silencing and innate immune activation properties may represent a new potential strategy for treatment of HBV.

  20. The Phase-I Trigger Readout Electronics Upgrade for the ATLAS Liquid-Argon Calorimeters

    CERN Document Server

    Ochoa, Ines; The ATLAS collaboration

    2017-01-01

    Electronics developments are pursued for the trigger readout of the ATLAS Liquid-Argon Calorimeter towards the Phase-I upgrade scheduled in the LHC shut-down period of 2019-2020. The LAr Trigger Digitizer system will digitize 34000 channels at a 40 MHz sampling with 12 bit precision after the bipolar shaper at the front-end system, and transmit to the LAr Digital Processing system in the back-end to extract the transverse energies. Results of ASIC developments including QA and radiation hardness evaluations, and performances on prototypes will presented with the overall system design.

  1. Upregulation of B7 molecules (CD80 and CD86) and exacerbated eosinophilic pulmonary inflammatory response in mice lacking the IFN-beta gene

    DEFF Research Database (Denmark)

    Matheu, Victor; Treschow, Alexandra; Navikas, Vaidrius

    2003-01-01

    . OBJECTIVE: We sought to define the differential role of endogenous IFN-beta in controlling the development of allergic inflammation. METHODS: We assessed whether deletion of the gene encoding IFN-beta (IFNB) with knockout mice participated in the development of allergic response in ovalbumin (OVA......BACKGROUND: IFN-beta has been shown to be effective as therapy for multiple sclerosis. Some reports attributed its beneficial effects to the capacity to induce a T(H)2 response. However, other studies have suggested that endogenous type I IFN might downregulate the allergic response in mice...

  2. Jet Exit Rig Six Component Force Balance

    Science.gov (United States)

    Castner, Raymond; Wolter, John; Woike, Mark; Booth, Dennis

    2012-01-01

    A new six axis air balance was delivered to the NASA Glenn Research Center. This air balance has an axial force capability of 800 pounds, primary airflow of 10 pounds per second, and a secondary airflow of 3 pounds per second. Its primary use was for the NASA Glenn Jet Exit Rig, a wind tunnel model used to test both low-speed, and high-speed nozzle concepts in a wind tunnel. This report outlines the installation of the balance in the Jet Exit Rig, and the results from an ASME calibration nozzle with an exit area of 8 square-inches. The results demonstrated the stability of the force balance for axial measurements and the repeatability of measurements better than 0.20 percent.

  3. Viral degradasome hijacks mitochondria to suppress innate immunity

    Science.gov (United States)

    Goswami, Ramansu; Majumdar, Tanmay; Dhar, Jayeeta; Chattopadhyay, Saurabh; Bandyopadhyay, Sudip K; Verbovetskaya, Valentina; Sen, Ganes C; Barik, Sailen

    2013-01-01

    The balance between the innate immunity of the host and the ability of a pathogen to evade it strongly influences pathogenesis and virulence. The two nonstructural (NS) proteins, NS1 and NS2, of respiratory syncytial virus (RSV) are critically required for RSV virulence. Together, they strongly suppress the type I interferon (IFN)-mediated innate immunity of the host cells by degrading or inhibiting multiple cellular factors required for either IFN induction or response pathways, including RIG-I, IRF3, IRF7, TBK1 and STAT2. Here, we provide evidence for the existence of a large and heterogeneous degradative complex assembled by the NS proteins, which we named “NS-degradasome” (NSD). The NSD is roughly ∼300-750 kD in size, and its degradative activity was enhanced by the addition of purified mitochondria in vitro. Inside the cell, the majority of the NS proteins and the substrates of the NSD translocated to the mitochondria upon RSV infection. Genetic and pharmacological evidence shows that optimal suppression of innate immunity requires mitochondrial MAVS and mitochondrial motility. Together, we propose a novel paradigm in which the mitochondria, known to be important for the innate immune activation of the host, are also important for viral suppression of the innate immunity. PMID:23877405

  4. IFN-λ and microRNAs are important modulators of the pulmonary innate immune response against influenza A (H1N2) infection in pigs

    DEFF Research Database (Denmark)

    Brogaard, Louise; Larsen, Lars E.; Heegaard, Peter Mikael Helweg

    2018-01-01

    the expression of miRNAs and protein coding genes in the lungs of pigs 1, 3, and 14 days after challenge with swine IAV (H1N2). Through RT-qPCR we observed a 400-fold relative increase in IFN-lambda 3 gene expression on day 1 after challenge, and a strong interferon-mediated antiviral response was observed......The innate immune system is paramount in the response to and clearance of influenza A virus (IAV) infection in non-immune individuals. Known factors include type I and III interferons and antiviral pathogen recognition receptors, and the cascades of antiviral and pro- and anti-inflammatory gene...

  5. The evaluation of secondary system oxygen-scavenging chemicals using a water-circulating rig

    Energy Technology Data Exchange (ETDEWEB)

    Collins, M.W. [Nuclear Dept., HMS Sultan (United Kingdom)

    2002-07-01

    To assess the efficiency, mode of action and possible by-products of chemical dosing agents, e.g. oxygen scavengers, a circulating water rig was constructed. The rig uses a demineralized water supply as a source of make-up water to fill a recirculating loop of approx. 10 litres volume. The rig pipework is made of polythene with standard off-the shelf pipe fittings and connectors. The following parameters can be measured within the rig: pH and conductivity measured by in-line monitor, dissolved oxygen level, temperature. The system has already been used for some preliminary testing. The following oxygen scavengers have been used for tests: ascorbic acid (vitamin C), N,N-diethyl-hydroxylamine (DEHA), Hydroquinone, hydrazine hydrate and anhydrous sodium sulfite. (authors)

  6. The evaluation of secondary system oxygen-scavenging chemicals using a water-circulating rig

    International Nuclear Information System (INIS)

    Collins, M.W.

    2002-01-01

    To assess the efficiency, mode of action and possible by-products of chemical dosing agents, e.g. oxygen scavengers, a circulating water rig was constructed. The rig uses a demineralized water supply as a source of make-up water to fill a recirculating loop of approx. 10 litres volume. The rig pipework is made of polythene with standard off-the shelf pipe fittings and connectors. The following parameters can be measured within the rig: pH and conductivity measured by in-line monitor, dissolved oxygen level, temperature. The system has already been used for some preliminary testing. The following oxygen scavengers have been used for tests: ascorbic acid (vitamin C), N,N-diethyl-hydroxylamine (DEHA), Hydroquinone, hydrazine hydrate and anhydrous sodium sulfite. (authors)

  7. Anti-inflammatory mechanisms of IFN-γ studied in experimental autoimmune encephalomyelitis reveal neutrophils as a potential target in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Nichole M Miller

    2015-08-01

    Full Text Available Multiple sclerosis (MS is an autoimmune disease of the central nervous system (CNS mediated by T helper (h1 and/or Th17 CD4 T cells that drive inflammatory lesion development along with demyelination and neuronal damage. Defects in immune regulatory mechanisms are thought to play a role in the pathogenesis of MS. While an early clinical trial indicated that IFN-γ administration was detrimental to MS, studies in the mouse model of MS, experimental autoimmune encephalomyelitis (EAE, indicated that IFN-γ exhibits a number of anti-inflammatory properties within the CNS. These mechanisms include inhibition of IL-17 production, induction of regulatory T cells, T cell apoptosis and regulation of chemokine production. Mice deficient in IFN-γ or its receptor were instrumental in deciphering the anti-inflammatory properties of IFN-γ in the CNS. In particular, they revealed that IFN-γ is a major regulator of neutrophil recruitment into the CNS, which by a variety of mechanisms including disruption of the blood-brain-barrier (BBB and production of reactive oxygen species are thought to contribute to the onset and progression of EAE. Neutrophils were also shown to be instrumental in EAE relapses. To date neutrophils have not been appreciated as a driver of MS, but more recently based largely on the strong EAE data this view is being reevaluated by some investigators in the field.

  8. Identification of novel macrolides with antibacterial, anti-inflammatory and type I and III IFN-augmenting activity in airway epithelium.

    Science.gov (United States)

    Porter, James D; Watson, Jennifer; Roberts, Lee R; Gill, Simren K; Groves, Helen; Dhariwal, Jaideep; Almond, Mark H; Wong, Ernie; Walton, Ross P; Jones, Lyn H; Tregoning, John; Kilty, Iain; Johnston, Sebastian L; Edwards, Michael R

    2016-10-01

    Exacerbations of asthma and COPD are triggered by rhinoviruses. Uncontrolled inflammatory pathways, pathogenic bacterial burden and impaired antiviral immunity are thought to be important factors in disease severity and duration. Macrolides including azithromycin are often used to treat the above diseases, but exhibit variable levels of efficacy. Inhaled corticosteroids are also readily used in treatment, but may lack specificity. Ideally, new treatment alternatives should suppress unwanted inflammation, but spare beneficial antiviral immunity. In the present study, we screened 225 novel macrolides and tested them for enhanced antiviral activity against rhinovirus, as well as anti-inflammatory activity and activity against Gram-positive and Gram-negative bacteria. Primary bronchial epithelial cells were grown from 10 asthmatic individuals and the effects of macrolides on rhinovirus replication were also examined. Another 30 structurally similar macrolides were also examined. The oleandomycin derivative Mac5, compared with azithromycin, showed superior induction (up to 5-fold, EC50 = 5-11 μM) of rhinovirus-induced type I IFNβ, type III IFNλ1 and type III IFNλ2/3 mRNA and the IFN-stimulated genes viperin and MxA, yet had no effect on IL-6 and IL-8 mRNA. Mac5 also suppressed rhinovirus replication at 48 h, proving antiviral activity. Mac5 showed antibacterial activity against Gram-positive Streptococcus pneumoniae; however, it did not have any antibacterial properties compared with azithromycin when used against Gram-negative Escherichia coli (as a model organism) and also the respiratory pathogens Pseudomonas aeruginosa and non-typeable Haemophilus influenzae. Further non-toxic Mac5 derivatives were identified with various anti-inflammatory, antiviral and antibacterial activities. The data support the idea that macrolides have antiviral properties through a mechanism that is yet to be ascertained. We also provide evidence that macrolides can be developed with

  9. Stochastic programming of drilling rigs supplies; Programacao estocastica de suprimentos de sondas

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Bruno Ferreira; Ferreira Filho, Virgilio Jose Martins [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil)

    2012-07-01

    The goal of this work is to use techniques of stochastic programming to reduce logistic costs regarding offshore drilling rigs. This theme is of great interest to Brazilian oil industry since there is an increasing number of wells that need to be perforated so that Brazilian oil production can reach its expected growth over the next ten years (PETROBRAS in particular has an ambitious strategy in this respect). Proper treatment of the uncertainties involved in the deliveries of supplies to offshore drilling rigs is essential, namely, these uncertainties need to be included in the models used in logistic models. Delays in the deliveries of products such as chemicals, perforation fluids and tubes may force drilling rigs to stop their operations what highly increases costs. The daily hiring rates of drilling rigs represent the highest cost in the perforation and completion of a well. (author)

  10. CD4(+) T cell-mediated control of a gamma-herpesvirus in B cell-deficient mice is mediated by IFN-gamma

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Cardin, R D; Branum, K C

    1999-01-01

    The lack of B cells and antibody does not prevent mice from dealing effectively with a pathogenic gamma-herpesvirus. Both CD4(+) and CD8(+) T cells contribute to the control of virus replication in the respiratory tract, with the depletion of either lymphocyte subset leading to increased titers...... for direct interaction with virus-infected targets expressing MHC class II glycoproteins, suggesting that the IFN-gamma produced by these lymphocytes is functioning at short range. The numbers of latently infected cells in the spleens of carrier mice are also significantly increased by the concurrent...

  11. Substantial Fatigue Similarity of a New Small-Scale Test Rig to Actual Wheel-Rail System

    NARCIS (Netherlands)

    Naeimi, M.; Li, Z.; Petrov, R.H.; Dollevoet, R.P.B.J.; Sietsma, J.; Wu, J.

    2014-01-01

    The substantial similarity of fatigue mechanism in a new test rig for rolling contact fatigue (RCF) has been investigated. A new reduced-scale test rig is designed to perform controlled RCF tests in wheel-rail materials. The fatigue mechanism of the rig is evaluated in this study using a combined

  12. Lessons from (triggered) tremor

    Science.gov (United States)

    Gomberg, Joan

    2010-01-01

    I test a “clock-advance” model that implies triggered tremor is ambient tremor that occurs at a sped-up rate as a result of loading from passing seismic waves. This proposed model predicts that triggering probability is proportional to the product of the ambient tremor rate and a function describing the efficacy of the triggering wave to initiate a tremor event. Using data mostly from Cascadia, I have compared qualitatively a suite of teleseismic waves that did and did not trigger tremor with ambient tremor rates. Many of the observations are consistent with the model if the efficacy of the triggering wave depends on wave amplitude. One triggered tremor observation clearly violates the clock-advance model. The model prediction that larger triggering waves result in larger triggered tremor signals also appears inconsistent with the measurements. I conclude that the tremor source process is a more complex system than that described by the clock-advance model predictions tested. Results of this and previous studies also demonstrate that (1) conditions suitable for tremor generation exist in many tectonic environments, but, within each, only occur at particular spots whose locations change with time; (2) any fluid flow must be restricted to less than a meter; (3) the degree to which delayed failure and secondary triggering occurs is likely insignificant; and 4) both shear and dilatational deformations may trigger tremor. Triggered and ambient tremor rates correlate more strongly with stress than stressing rate, suggesting tremor sources result from time-dependent weakening processes rather than simple Coulomb failure.

  13. Alcohol Enhances HIV Infection of Cord Blood Monocyte-Derived Macrophages

    Science.gov (United States)

    Mastrogiannis, Dimitrios S.; Wang, Xu; Dai, Min; Li, Jieliang; Wang, Yizhong; Zhou, Yu; Sakarcan, Selin; Peña, Juliet Crystal; Ho, Wenzhe

    2014-01-01

    Alcohol consumption or alcohol abuse is common among pregnant HIV+ women and has been identified as a potential behavioral risk factor for the transmission of HIV. In this study, we examined the impact of alcohol on HIV infection of cord blood monocyte-derived macrophages (CBMDM). We demonstrated that alcohol treatment of CBMDM significantly enhanced HIV infection of CBMDM. Investigation of the mechanisms of alcohol action on HIV demonstrated that alcohol inhibited the expression of several HIV restriction factors, including anti-HIV microRNAs, APOBEC3G and APOBEC3H. Additionally, alcohol also suppressed the expression of IFN regulatory factor 7 (IRF-7) and retinoic acid-inducible gene I (RIG-I), an intracellular sensor of viral infection. The suppression of these IFN regulatory factors was associated with reduced expression of type I IFN. These experimental findings suggest that maternal alcohol consumption may facilitate HIV infection, promoting vertical transmission of HIV. PMID:25053361

  14. Work over rig itinerary optimization; Otimizacao do itinerario de sondas de intervencao

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Ronaldo Oliveira de

    1997-07-01

    The costs of work over and the loss of revenue in wells waiting work over rigs are very high. This work proposes methods to prioritize these wells in order to minimize the total cost. To determine the work over sequence it is necessary to compare the rig expense with the wells losses. For calculating the wells losses, it is necessary to analyze the monetary influence of the well shutdown in the production curves. In this work, this analysis is made by using a numerical reservoir simulator. Simplified calculation procedures are also presented. The priority of the wells is based on the reduction of the total cost, which consists of the rig costs plus the revenue losses due to work over waiting. There are many algorithms able to determine the ideal rig path. Simple and intuitive algorithms are implemented and compared. The Simulated Annealing algorithm is recommended. This algorithm was implemented to optimize work over rig routes in a brazilian production region. Optimization of the work over sequence carried out in that region in 1996 identified a potential economy of 15% in the production losses, equivalent to 4.000m{sup 3}/year of oil (25.000 b bl/year). (author)

  15. Development of TIG Welding System for a Nuclear Fuel Test Rig

    Energy Technology Data Exchange (ETDEWEB)

    Joung, Changyoung; Ahn, Sungho; Hong, Jintae; Kim, Kahye [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    The welding process is one of the most important among the instrumentation processes of the nuclear fuel test rig and rods. To manufacture the nuclear fuel test rig, a precision welding system needs to be fabricated to develop various welding technologies of the fuel test rig and rods jointing the various sensors and end caps on a fuel cladding tube, which is charged with fuel pellets and component parts. Thus, we designed and fabricated the precision welding system consisting of an orbital TIG welder, a low-pressure chamber, and a high-pressure chamber. Using this system, the performance tests were performed with the round and seal spot welds for each welding condition. This paper describes not only the contents for the fabrication of precision TIG welding system but also some results from weld tests using the low-pressure and high-pressure chambers to verify the performance of this system. The TIG welding system was developed to manufacture the nuclear fuel test rig and rods. It has been configured to be able to weld the nuclear fuel test rigs and rods by applying the TIG welder using a low-pressure chamber and a high-pressure chamber. The performance tests using this system were performed with the round and seal spot welds for the welding conditions. The soundness of the orbital TIG welding system was confirmed through performance tests in the low-pressure and high-pressure chambers.

  16. Development of TIG Welding System for a Nuclear Fuel Test Rig

    International Nuclear Information System (INIS)

    Joung, Changyoung; Ahn, Sungho; Hong, Jintae; Kim, Kahye

    2013-01-01

    The welding process is one of the most important among the instrumentation processes of the nuclear fuel test rig and rods. To manufacture the nuclear fuel test rig, a precision welding system needs to be fabricated to develop various welding technologies of the fuel test rig and rods jointing the various sensors and end caps on a fuel cladding tube, which is charged with fuel pellets and component parts. Thus, we designed and fabricated the precision welding system consisting of an orbital TIG welder, a low-pressure chamber, and a high-pressure chamber. Using this system, the performance tests were performed with the round and seal spot welds for each welding condition. This paper describes not only the contents for the fabrication of precision TIG welding system but also some results from weld tests using the low-pressure and high-pressure chambers to verify the performance of this system. The TIG welding system was developed to manufacture the nuclear fuel test rig and rods. It has been configured to be able to weld the nuclear fuel test rigs and rods by applying the TIG welder using a low-pressure chamber and a high-pressure chamber. The performance tests using this system were performed with the round and seal spot welds for the welding conditions. The soundness of the orbital TIG welding system was confirmed through performance tests in the low-pressure and high-pressure chambers

  17. Comprehensive Antiretroviral Restriction Factor Profiling Reveals the Evolutionary Imprint of the ex Vivo and in Vivo IFN-β Response in HTLV-1-Associated Neuroinflammation

    Directory of Open Access Journals (Sweden)

    Fabio E. Leal

    2018-05-01

    Full Text Available HTLV-1-Associated Myelopathy (HAM/TSP is a progressive neuroinflammatory disorder for which no disease-modifying treatment exists. Modest clinical benefit from type I interferons (IFN-α/β in HAM/TSP contrasts with its recently identified IFN-inducible gene signature. In addition, IFN-α treatment in vivo decreases proviral load and immune activation in HAM/TSP, whereas IFN-β therapy decreases tax mRNA and lymphoproliferation. We hypothesize this “IFN paradox” in HAM/TSP might be explained by both cell type- and gene-specific effects of type I IFN in HTLV-1-associated pathogenesis. Therefore, we analyzed ex vivo transcriptomes of CD4+ T cells, PBMCs and whole blood in healthy controls, HTLV-1-infected individuals, and HAM/TSP patients. First, we used a targeted approach, simultaneously quantifying HTLV-1 mRNA (HBZ, Tax, proviral load and 42 host genes with known antiretroviral (anti-HIV activity in purified CD4+ T cells. This revealed two major clusters (“antiviral/protective” vs. “proviral/deleterious”, as evidenced by significant negative (TRIM5/TRIM22/BST2 vs. positive correlation (ISG15/PAF1/CDKN1A with HTLV-1 viral markers and clinical status. Surprisingly, we found a significant inversion of antiretroviral activity of host restriction factors, as evidenced by opposite correlation to in vivo HIV-1 vs. HTLV-1 RNA levels. The anti-HTLV-1 effect of antiviral cluster genes was significantly correlated to their adaptive chimp/human evolution score, for both Tax mRNA and PVL. Six genes of the proposed antiviral cluster underwent lentivirus-driven purifying selection during primate evolution (TRIM5/TRIM22/BST2/APOBEC3F-G-H, underscoring the cross-retroviral evolutionary imprint. Secondly, we examined the genome-wide type I IFN response in HAM/TSP patients, following short-term ex vivo culture of PBMCs with either IFN-α or IFN-β. Microarray analysis evidenced 12 antiretroviral genes (including TRIM5α/TRIM22/BST2 were significantly

  18. Type I and type II interferons upregulate functional type I interleukin-1 receptor in a human fibroblast cell line TIG-1.

    Science.gov (United States)

    Takii, T; Niki, N; Yang, D; Kimura, H; Ito, A; Hayashi, H; Onozaki, K

    1995-12-01

    The regulation of type I interleukin-1 receptor (IL-1R) expression by type I, interferon (IFN)-alpha A/D, and type II IFN, IFN-gamma, in a human fibroblast cell line TIG-1 was investigated. After 2 h stimulation with human IFN-alpha A/D or IFN-gamma, the levels of type I IL-1R mRNA increased. We previously reported that IL-1 upregulates transcription and cell surface molecules of type I IL-1R in TIG-1 cells through induction of prostaglandin (PG) E2 and cAMP accumulation. However, indomethacin was unable to inhibit the effect of IFNs, indicating that IFNs augment IL-1R expression through a pathway distinct from that of IL-1. The augmentation was also observed in other fibroblast cell lines. Nuclear run-on assays and studies of the stability of mRNA suggested that the increase in IL-1R mRNA was a result of the enhanced transcription of IL-1R gene. Binding studies using 125I-IL-1 alpha revealed that the number of cell surface IL-1R increased with no change in binding affinity by treatment with these IFNs. Pretreatment of the cells with IFNs enhanced IL-1-induced IL-6 production, indicating that IFNs upregulate functional IL-1R. IL-1 and IFNs are produced by the same cell types, as well as by the adjacent different cell types, and are concomitantly present in lesions of immune and inflammatory reactions. These results therefore suggest that IFNs exhibit synergistic effects with IL-1 through upregulation of IL-1R. Augmented production of IL-6 may also contribute to the reactions.

  19. Characteristics of alpha/beta interferon induction after infection of murine fibroblasts with wild-type and mutant alphaviruses

    International Nuclear Information System (INIS)

    Burke, Crystal W.; Gardner, Christina L.; Steffan, Joshua J.; Ryman, Kate D.; Klimstra, William B.

    2009-01-01

    We examined the characteristics of interferon alpha/beta (IFN-α/β) induction after alphavirus or control Sendai virus (SeV) infection of murine fibroblasts (MEFs). As expected, SeV infection of wild-type (wt) MEFs resulted in strong dimerization of IRF3 and the production of high levels of IFN-α/β. In contrast, infection of MEFs with multiple alphaviruses failed to elicit detectable IFN-α/β. In more detailed studies, Sindbis virus (SINV) infection caused dimerization and nuclear migration of IRF3, but minimal IFN-β promoter activity, although surprisingly, the infected cells were competent for IFN production by other stimuli early after infection. A SINV mutant defective in host macromolecular synthesis shutoff induced IFN-α/β in the MEF cultures dependent upon the activities of the TBK1 IRF3 activating kinase and host pattern recognition receptors (PRRs) PKR and MDA5 but not RIG-I. These results suggest that wild-type alphaviruses antagonize IFN induction after IRF3 activation but also may avoid detection by host PRRs early after infection.

  20. Re-rigging Othering: Subversive Infantilisation in Contemporary Bosnian-Herzegovinian Prose

    Directory of Open Access Journals (Sweden)

    Fedja Borčak

    2014-12-01

    Full Text Available In this article I put forward the concept of subversive infantilisation to designate a phenomenon in contemporary Bosnian literature, which by using a certain kind of childish outlook on the world undermines paternalistic and balkanist Western discourse on Bosnia and Herzegovina. By analysing primarily the portrayal of the role of mass media in a few literary texts, principally books by Nenad Veličkovié and Miljenko Jergovié, I highlight the way in which these texts 're-rig' and by means of irony and exaggeration illuminate the problematic logic inherent in the subject position from which one represents the other. Textual characteristics of subversive infantilisation are contextualised further and seen as a discursive continuation of experiences of the 1990s war in Bosnia and Herzegovina.

  1. Role of IFN-gamma and IL-6 in a protective immune response to Yersinia enterocolitica in mice

    Directory of Open Access Journals (Sweden)

    Autenrieth Ingo B

    2008-09-01

    Full Text Available Abstract Background Yersinia outer protein (Yop H is a secreted virulence factor of Yersinia enterocolitica (Ye, which inhibits phagocytosis of Ye and contributes to the virulence of Ye in mice. The aim of this study was to address whether and how YopH affects the innate immune response to Ye in mice. Results For this purpose, mice were infected with wild type Ye (pYV+ or a YopH-deficient Ye mutant strain (ΔyopH. CD11b+ cells were isolated from the infected spleen and subjected to gene expression analysis using microarrays. Despite the attenuation of ΔyopH in vivo, by variation of infection doses we were able to achieve conditions that allow comparison of gene expression in pYV+ and ΔyopH infection, using either comparable infection courses or splenic bacterial burden. Gene expression analysis provided evidence that expression levels of several immune response genes, including IFN-γ and IL-6, are high after pYV+ infection but low after sublethal ΔyopH infection. In line with these findings, infection of IFN-γR-/- and IL-6-/- mice with pYV+ or ΔyopH revealed that these cytokines are not necessarily required for control of ΔyopH, but are essential for defense against infection with the more virulent pYV+. Consistently, IFN-γ pretreatment of bone marrow derived macrophages (BMDM strongly enhanced their ability in killing intracellular Ye bacteria. Conclusion In conclusion, this data suggests that IFN-γ-mediated effector mechanisms can partially compensate virulence exerted by YopH. These results shed new light on the protective role of IFN-γ in Ye wild type infections.

  2. Intra-abdominal recurrence of colorectal cancer detected by radioimmunoguided surgery (RIGS system)

    International Nuclear Information System (INIS)

    Sardi, A.; Workman, M.; Mojzisik, C.; Hinkle, G.; Nieroda, C.; Martin, E.W. Jr.

    1989-01-01

    Since 1986, 32 patients with metastatic colorectal cancer have undergone second-look radioimmunoguided surgery (RIGS system). The primary tumor was located in the right and transverse colon in 11 patients, left and sigmoid colon in 16, and rectum in five. The carcinoembryonic antigen level was elevated in 30 patients (94%); all patients underwent a computed tomographic scan of the abdomen and pelvis. The overall sensitivity of the computed tomographic scan was 41% (abdomen other than liver, 27%; liver, 58%; and pelvis, 22%). The RIGS system identified recurrent tumor in 81% of the patients. The most common site of metastasis was the liver (41%), independent of the primary location. Local/regional recurrences alone accounted for 40% of all recurrences. In six patients (18%), recurrent tumor was found only with the RIGS system. The RIGS system is more dependable in localizing clinically obscure metastases than other methods, and carcinoembryonic antigen testing remains the most accurate preoperative method to indicate suspected recurrences

  3. The Phase-I Trigger Readout Electronics Upgrade of the ATLAS Liquid Argon Calorimeters

    CERN Document Server

    Enari, Yuji; The ATLAS collaboration

    2018-01-01

    Electronics developments are pursued for the trigger readout of the ATLAS Liquid-Argon Calorimeter towards the Phase-I upgrade scheduled in the LHC shut-down period of 2019-2020. The LAr Trigger Digitizer system will digitize 34000 channels at a 40 MHz sampling with 12 bit precision after the bipolar shaper at the front-end system, and transmit to the LAr Digital Processing system in the back-end to extract the transverse energies. Results of ASIC developments including QA and radiation hardness evaluations, performances of the final prototypes and results of the system integration tests will presented along with the overall system design.

  4. Increased Bone Marrow (BM) Plasma Level of Soluble CD30 and Correlations with BM Plasma Level of Interferon (IFN)-γ, CD4/CD8 T-Cell Ratio and Disease Severity in Aplastic Anemia

    Science.gov (United States)

    Shi, Jun; Ge, Meili; Li, Xingxin; Shao, Yingqi; Yao, Jianfeng; Zheng, Yizhou

    2014-01-01

    Idiopathic aplastic anemia (AA) is an immune-mediated bone marrow failure syndrome. Immune abnormalities such as decreased lymphocyte counts, inverted CD4/CD8 T-cell ratio and increased IFN-γ-producing T cells have been found in AA. CD30, a surface protein belonging to the tumor necrosis factor receptor family and releasing from cell surface as a soluble form (sCD30) after activation, marks a subset of activated T cells secreting IFN-γ when exposed to allogeneic antigens. Our study found elevated BM plasma levels of sCD30 in patients with SAA, which were closely correlated with disease severity, including absolute lymphocyte count (ALC) and absolute netrophil count (ANC). We also noted that sCD30 levels were positively correlated with plasma IFN-γ levels and CD4/CD8 T-cell ratio in patients with SAA. In order to explain these phenomena, we stimulated T cells with alloantigen in vitro and found that CD30+ T cells were the major source of IFN-γ, and induced CD30+ T cells from patients with SAA produced significantly more IFN-γ than that from healthy individuals. In addition, increased proportion of CD8+ T cells in AA showed enhanced allogeneic response by the fact that they expressed more CD30 during allogeneic stimulation. sCD30 levels decreased in patients responded to immunosuppressive therapy. In conclusion, elevated BM plasma levels of sCD30 reflected the enhanced CD30+ T cell-mediated immune response in SAA. CD30 as a molecular marker that transiently expresses on IFN-γ-producing T cells, may participate in mediating bone marrow failure in AA, which also can facilitate our understanding of AA pathogenesis to identify new therapeutic targets. PMID:25383872

  5. Computer aided extractor design for the RIG 10 high intensity ion source

    International Nuclear Information System (INIS)

    Tanzer, F.; Haeuser, J.; Eppel, D.

    1980-01-01

    The paper discusses recent progress of the rf-ion source RIG 10, and describes a computer code for the simulation of the ion trajectories. The RIG 10 is designed for current densities of some 300 mA/cm 2 , and will be used for the production of neutral. (orig.)

  6. Environmental triggers of thyroiditis: hepatitis C and interferon-α.

    Science.gov (United States)

    Menconi, F; Hasham, A; Tomer, Y

    2011-01-01

    Autoimmune thyroid diseases (AITD) are postulated to develop as a result of a complex interplay between several genetic and environmental influences. The pathogenesis of AITD is still not clearly defined. However, among the implicated triggers (e.g. iodine, infections, medications), more recent data confirmed strong associations of AITD with the hepatitis C virus (HCV) infection and interferon-α (IFNα) therapy. Moreover, it is likely that HCV and IFN act in synergism to trigger AITD in patients. Indeed, approximately 40% of HCV patients develop either clinical or subclinical disease while receiving IFNα. Interferon induced thyroiditis (IIT) can manifest as non-autoimmune thyroiditis (presenting as destructive thyroiditis, or non-autoimmune hypothyroidism), or autoimmune thyroiditis [presenting with clinical features of Graves' disease (GD) or Hashimoto's thyroiditis (HT)]. Although not yet clearly understood, it is thought that IFNα can induce thyroiditis via both immune stimulatory and direct toxic effects on the thyroid. In view of the high frequency of IIT, routine screening and surveillance of HCV patients receiving IFNα is recommended to avoid the complications, such as cardiac arrhythmias, associated with thyrotoxicosis. In summary, IIT is a common clinical problem that can be readily diagnosed with routine thyroid function screening of HCV patients receiving IFN. The treatment of IIT consists of the standard therapy for differing clinical manifestations of IIT such as GD, HT, or destructive thyroiditis. However, anti-thyroid medications are not recommended in this setting since they can potentially be hepatotoxic.

  7. This immortal coil? New CT rigs duel against singles

    Energy Technology Data Exchange (ETDEWEB)

    Creighton, J.

    1998-12-01

    New competition to conventional single rigs that have changed little in the last four decades face new competition from next-generation coiled tubing (CT) units which have multi-function capabilities, ranging from driving onto leases, drilling and setting surface case to cementing. Several of these new units are ready to challenge the conventional single rigs. Their ability to perform at high penetration rates (up to twice what single rigs can do) is expected to significantly cut drill time, with corresponding cost savings for both contractors and operators. Serval Corporation and Fleet Coiled Services are just two of the drilling service companies that have launched new shallow grass roots coiled tubing drilling units recently, gambling that the new technology will win over conventional methods hands down. Some major companies, like Fracmaster Ltd. and NOWSCO Well Service Ltd., have targeted the re-entry and horizontal markets, a much more difficult technical challenge, sinking billions of dollars of research and development money into advancing the most technically difficult applications of coil technology.

  8. IFN-gamma-inducible Irga6 mediates host resistance against Chlamydia trachomatis via autophagy.

    Directory of Open Access Journals (Sweden)

    Munir A Al-Zeer

    Full Text Available Chlamydial infection of the host cell induces Gamma interferon (IFNgamma, a central immunoprotector for humans and mice. The primary defense against Chlamydia infection in the mouse involves the IFNgamma-inducible family of IRG proteins; however, the precise mechanisms mediating the pathogen's elimination are unknown. In this study, we identify Irga6 as an important resistance factor against C. trachomatis, but not C. muridarum, infection in IFNgamma-stimulated mouse embryonic fibroblasts (MEFs. We show that Irga6, Irgd, Irgm2 and Irgm3 accumulate at bacterial inclusions in MEFs upon stimulation with IFNgamma, whereas Irgb6 colocalized in the presence or absence of the cytokine. This accumulation triggers a rerouting of bacterial inclusions to autophagosomes that subsequently fuse to lysosomes for elimination. Autophagy-deficient Atg5-/- MEFs and lysosomal acidification impaired cells surrender to infection. Irgm2, Irgm3 and Irgd still localize to inclusions in IFNgamma-induced Atg5-/- cells, but Irga6 localization is disrupted indicating its pivotal role in pathogen resistance. Irga6-deficient (Irga6-/- MEFs, in which chlamydial growth is enhanced, do not respond to IFNgamma even though Irgb6, Irgd, Irgm2 and Irgm3 still localize to inclusions. Taken together, we identify Irga6 as a necessary factor in conferring host resistance by remodelling a classically nonfusogenic intracellular pathogen to stimulate fusion with autophagosomes, thereby rerouting the intruder to the lysosomal compartment for destruction.

  9. CMS Calorimeter Trigger Phase I upgrade

    International Nuclear Information System (INIS)

    Klabbers, P; Gorski, T; Bachtis, M; Dasu, S; Fobes, R; Grothe, M; Ross, I; Smith, W H; Compton, K; Farmahini-Farahani, A; Gregerson, A; Seemuth, D; Schulte, M

    2012-01-01

    We present a design for the Phase-1 upgrade of the Compact Muon Solenoid (CMS) calorimeter trigger system composed of FPGAs and Multi-GBit/sec links that adhere to the μTCA crate Telecom standard. The upgrade calorimeter trigger will implement algorithms that create collections of isolated and non-isolated electromagnetic objects, isolated and non-isolated tau objects and jet objects. The algorithms are organized in several steps with progressive data reduction. These include a particle cluster finder that reconstructs overlapping clusters of 2x2 calorimeter towers and applies electron identification, a cluster overlap filter, particle isolation determination, jet reconstruction, particle separation and sorting.

  10. Interferon-lambda contributes to innate immunity of mice against influenza A virus but not against hepatotropic viruses

    DEFF Research Database (Denmark)

    Mordstein, M; Kochs, G; Dumoutier, L

    2008-01-01

    Virus-infected cells secrete a broad range of interferon (IFN) subtypes which in turn trigger the synthesis of antiviral factors that confer host resistance. IFN-alpha, IFN-beta and other type I IFNs signal through a common universally expressed cell surface receptor, whereas IFN-lambda uses....... Mice lacking functional IFN-lambda receptors were only slightly more susceptible to influenza virus than wild-type mice. However, mice lacking functional receptors for both IFN-alpha/beta and IFN-lambda were hypersensitive and even failed to restrict usually non-pathogenic influenza virus mutants...

  11. TRIGGER

    CERN Multimedia

    by Wesley Smith

    2011-01-01

    Level-1 Trigger Hardware and Software After the winter shutdown minor hardware problems in several subsystems appeared and were corrected. A reassessment of the overall latency has been made. In the TTC system shorter cables between TTCci and TTCex have been installed, which saved one bunch crossing, but which may have required an adjustment of the RPC timing. In order to tackle Pixel out-of-syncs without influencing other subsystems, a special hardware/firmware re-sync protocol has been introduced in the Global Trigger. The link between the Global Calorimeter Trigger and the Global Trigger with the new optical Global Trigger Interface and optical receiver daughterboards has been successfully tested in the Electronics Integration Centre in building 904. New firmware in the GCT now allows a setting to remove the HF towers from energy sums. The HF sleeves have been replaced, which should lead to reduced rates of anomalous signals, which may allow their inclusion after this is validated. For ECAL, improvements i...

  12. Highly Pathogenic H5N1 Influenza A Virus Strains Provoke Heterogeneous IFN-α/β Responses That Distinctively Affect Viral Propagation in Human Cells

    Science.gov (United States)

    Matthaei, Markus; Budt, Matthias; Wolff, Thorsten

    2013-01-01

    The fatal transmissions of highly pathogenic avian influenza A viruses (IAV) of the H5N1 subtype to humans and high titer replication in the respiratory tract indicate that these pathogens can overcome the bird-to-human species barrier. While type I interferons (IFN-α/β) are well described to contribute to the species barrier of many zoonotic viruses, current data to the role of these antiviral cytokines during human H5N1 IAV infections is limited and contradictory. We hypothesized an important role for the IFN system in limiting productive infection of avian H5N1 strains in human cells. Hence, we examined IFN-α/β gene activation by different avian and human H5N1 isolates, if the IFN-α/β response restricts H5N1 growth and whether the different strains were equally capable to regulate the IFN-α/β system via their IFN-antagonistic NS1 proteins. Two human H5N1 isolates and a seasonal H3N2 strain propagated efficiently in human respiratory cells and induced little IFN-β, whereas three purely avian H5N1 strains were attenuated for replication and provoked higher IFN secretion. Replication of avian viruses was significantly enhanced on interferon-deficient cells, and exogenous IFN potently limited the growth of all strains in human cells. Moreover, IFN-α/β activation by all strains depended on retinoic acid-inducible gene I excluding principal differences in receptor activation between the different viruses. Interestingly, all H5N1 NS1 proteins suppressed IFN-α/β induction comparably well to the NS1 of seasonal IAV. Thus, our study shows that H5N1 strains are heterogeneous in their capacity to activate human cells in an NS1-independent manner. Our findings also suggest that H5N1 viruses need to acquire adaptive changes to circumvent strong IFN-α/β activation in human host cells. Since no single amino acid polymorphism could be associated with a respective high- or low induction phenotype we propose that the necessary adaptations to overcome the human IFN

  13. Highly pathogenic H5N1 influenza A virus strains provoke heterogeneous IFN-α/β responses that distinctively affect viral propagation in human cells.

    Directory of Open Access Journals (Sweden)

    Markus Matthaei

    Full Text Available The fatal transmissions of highly pathogenic avian influenza A viruses (IAV of the H5N1 subtype to humans and high titer replication in the respiratory tract indicate that these pathogens can overcome the bird-to-human species barrier. While type I interferons (IFN-α/β are well described to contribute to the species barrier of many zoonotic viruses, current data to the role of these antiviral cytokines during human H5N1 IAV infections is limited and contradictory. We hypothesized an important role for the IFN system in limiting productive infection of avian H5N1 strains in human cells. Hence, we examined IFN-α/β gene activation by different avian and human H5N1 isolates, if the IFN-α/β response restricts H5N1 growth and whether the different strains were equally capable to regulate the IFN-α/β system via their IFN-antagonistic NS1 proteins. Two human H5N1 isolates and a seasonal H3N2 strain propagated efficiently in human respiratory cells and induced little IFN-β, whereas three purely avian H5N1 strains were attenuated for replication and provoked higher IFN secretion. Replication of avian viruses was significantly enhanced on interferon-deficient cells, and exogenous IFN potently limited the growth of all strains in human cells. Moreover, IFN-α/β activation by all strains depended on retinoic acid-inducible gene I excluding principal differences in receptor activation between the different viruses. Interestingly, all H5N1 NS1 proteins suppressed IFN-α/β induction comparably well to the NS1 of seasonal IAV. Thus, our study shows that H5N1 strains are heterogeneous in their capacity to activate human cells in an NS1-independent manner. Our findings also suggest that H5N1 viruses need to acquire adaptive changes to circumvent strong IFN-α/β activation in human host cells. Since no single amino acid polymorphism could be associated with a respective high- or low induction phenotype we propose that the necessary adaptations to

  14. Systemic Virus Infections Differentially Modulate Cell Cycle State and Functionality of Long-Term Hematopoietic Stem Cells In Vivo

    Directory of Open Access Journals (Sweden)

    Christoph Hirche

    2017-06-01

    Full Text Available Quiescent long-term hematopoietic stem cells (LT-HSCs are efficiently activated by type I interferon (IFN-I. However, this effect remains poorly investigated in the context of IFN-I-inducing virus infections. Here we report that both vesicular stomatitis virus (VSV and murine cytomegalovirus (MCMV infection induce LT-HSC activation that substantially differs from the effects triggered upon injection of synthetic IFN-I-inducing agents. In both infections, inflammatory responses had to exceed local thresholds within the bone marrow to confer LT-HSC cell cycle entry, and IFN-I receptor triggering was not critical for this activation. After resolution of acute MCMV infection, LT-HSCs returned to phenotypic quiescence. However, non-acute MCMV infection induced a sustained inflammatory milieu within the bone marrow that was associated with long-lasting impairment of LT-HSC function. In conclusion, our results show that systemic virus infections fundamentally affect LT-HSCs and that also non-acute inflammatory stimuli in bone marrow donors can affect the reconstitution potential of bone marrow transplants.

  15. Systemic Virus Infections Differentially Modulate Cell Cycle State and Functionality of Long-Term Hematopoietic Stem Cells In Vivo.

    Science.gov (United States)

    Hirche, Christoph; Frenz, Theresa; Haas, Simon F; Döring, Marius; Borst, Katharina; Tegtmeyer, Pia-K; Brizic, Ilija; Jordan, Stefan; Keyser, Kirsten; Chhatbar, Chintan; Pronk, Eline; Lin, Shuiping; Messerle, Martin; Jonjic, Stipan; Falk, Christine S; Trumpp, Andreas; Essers, Marieke A G; Kalinke, Ulrich

    2017-06-13

    Quiescent long-term hematopoietic stem cells (LT-HSCs) are efficiently activated by type I interferon (IFN-I). However, this effect remains poorly investigated in the context of IFN-I-inducing virus infections. Here we report that both vesicular stomatitis virus (VSV) and murine cytomegalovirus (MCMV) infection induce LT-HSC activation that substantially differs from the effects triggered upon injection of synthetic IFN-I-inducing agents. In both infections, inflammatory responses had to exceed local thresholds within the bone marrow to confer LT-HSC cell cycle entry, and IFN-I receptor triggering was not critical for this activation. After resolution of acute MCMV infection, LT-HSCs returned to phenotypic quiescence. However, non-acute MCMV infection induced a sustained inflammatory milieu within the bone marrow that was associated with long-lasting impairment of LT-HSC function. In conclusion, our results show that systemic virus infections fundamentally affect LT-HSCs and that also non-acute inflammatory stimuli in bone marrow donors can affect the reconstitution potential of bone marrow transplants. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. The CXC chemokines gamma interferon (IFN-gamma)-inducible protein 10 and monokine induced by IFN-gamma are released during severe melioidosis

    NARCIS (Netherlands)

    Lauw, F. N.; Simpson, A. J.; Prins, J. M.; van Deventer, S. J.; Chaowagul, W.; White, N. J.; van der Poll, T.

    2000-01-01

    Gamma interferon (IFN-gamma)-inducible protein 10 (IP-10) and monokine induced by IFN-gamma (Mig) are related CXC chemokines which bind to the CXCR3 receptor and specifically target activated T lymphocytes and natural killer (NK) cells. The production of IP-10 and Mig by various cell types in vitro

  17. Transmission of HBV DNA Mediated by Ceramide-Triggered Extracellular VesiclesSummary

    Directory of Open Access Journals (Sweden)

    Takahiro Sanada

    2017-03-01

    Full Text Available Background & Aims: An extracellular vesicle (EV is a nanovesicle that shuttles proteins, nucleic acids, and lipids, thereby influencing cell behavior. A recent crop of reports have shown that EVs are involved in infectious biology, influencing host immunity and playing a role in the viral life cycle. In the present work, we investigated the EV-mediated transmission of hepatitis B virus (HBV infection. Methods: We investigated the EV-mediated transmission of HBV infection by using a HBV infectious culture system that uses primary human hepatocytes derived from humanized chimeric mice (PXB-cells. Purified EVs were isolated by ultracentrifugation. To analyze the EVs and virions, we used stimulated emission depletion microscopy. Results: Purified EVs from HBV-infected PXB-cells were shown to contain HBV DNA and to be capable of transmitting HBV DNA to naive PXB-cells. These HBV-DNA–transmitting EVs were shown to be generated through a ceramide-triggered EV production pathway. Furthermore, we showed that these HBV-DNA–transmitting EVs were resistant to antibody neutralization; stimulated emission depletion microscopy showed that EVs lacked hepatitis B surface antigen, the target of neutralizing antibodies. Conclusions: These findings suggest that EVs harbor a DNA cargo capable of transmitting viral DNA into hepatocytes during HBV infection, representing an additional antibody-neutralization–resistant route of HBV infection. Keywords: HBV, Extracellular Vesicles, Transmission Pathway

  18. Role of IL-12 and IFN-γ in immune response to toxoplasma gondii infection

    International Nuclear Information System (INIS)

    Moawad, M.A.F.; ElGawish, M.A.M.

    2004-01-01

    Interlenkin 12 (IL-12) is a potent immunoregulatory molecule that is critically involved in a wide range of diseases. In several murine models of intracellular infection, endogenous IL-12 has been shown to be crucial for the generation of a protective Th1 response in a primary infection for a intracellular pathogens. Interferon-gamma (IFN-γ) is also an important mediator of cellular immunity against microbial pathogens and tumor cells due to its potent capacity to activate macrophages for enhanced cytotoxicity. The aim of the present study is to evaluate the immune response to toxoplasma gondii after primary inflection (infected groups and secondary infection (re-infected groups for over 19 weeks (the time of the experiment). the evaluation was assessed by measurements of levels of IL-12 and IFN-γ using ELISA technique in the sera of these infected rats. The results demonstrated that the primary immune response induced a fluctuation in the levels of IL-12 in the sera of infected rats, which reached maximum value of 122.6 ±1.4 pg/ml after 15 weeks of primary infection. While, in the challenged groups (secondary immune response, re-infected groups) the levels of IL-12 were generally lower than that of the primary immune response. On the other hand, IFN-γ levels increased significantly in the secondary immune response (re-infected groups) as compared to primary immune response 9 infected groups) In conclusion, the results suggest that IL-12 might have a role in the defense mechanism against intracellular infection with T-gondii especially in primary immune response than in the secondary immune response. This is in contrast to IFN-γ that takes the up-hand in secondary immune response to T-gondii infection

  19. Triggering at high luminosity: fake triggers from pile-up

    International Nuclear Information System (INIS)

    Johnson, R.

    1983-01-01

    Triggers based on a cut in transverse momentum (p/sub t/) have proved to be useful in high energy physics both because they indicte that a hard constituent scattering has occurred and because they can be made quickly enough to gate electronics. These triggers will continue to be useful at high luminosities if overlapping events do not cause an excessive number of fake triggers. In this paper, I determine if this is indeed a problem at high luminosity machines

  20. Identification of amino-acid residues in the V protein of peste des petits ruminants essential for interference and suppression of STAT-mediated interferon signaling

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xusheng, E-mail: maxushengtt@163.com [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730030 (China); Yang, Xing [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730030 (China); Nian, Xiaofeng [Institute of Pathogen Biology and Immunology, Hebei North University, Zhangjiakou 07500 (China); Zhang, Zhidong; Dou, Yongxi [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730030 (China); Zhang, Xuehu [Gansu Agricultural University, Lanzhou (China); Luo, Xuenong; Su, Junhong; Zhu, Qiyun [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730030 (China); Cai, Xuepeng, E-mail: caixp@vip.163.com [State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730030 (China)

    2015-09-15

    Peste des petits ruminants virus (PPRV) causes a fatal disease in small ruminants. V protein of PPRV plays a pivotal role in interfering with host innate immunity by blocking IFNs signaling through interacting with STAT1 and STAT2. In the present study, the results demonstrated that PPRV V protein blocks IFN actions in a dose dependent manner and restrains the translocation of STAT1/2 proteins. We speculate that the translocation inhibition might be caused by the interfering of the downstream of STAT protein. Mutagenesis defines that Cys cluster and Trp motif of PPRV V protein are essential for STAT-mediated IFN signaling. These findings give a new sight for the further studies to understand the delicate mechanism of PPRV to escape the IFN signaling. - Highlights: • PPRV V protein inhibits type I IFN production and blocks its activation. • PPRV V protein negatively regulates activation of ISRE and GAS promoter. • PPRV V protein inhibits nuclear translocation of STAT protein by non-degradation. • PNT and VCT domain of PPRV V protein inhibit IFN transduction. • PPRV V protein binds with STAT protein via some conserved motifs.

  1. The cost of successful antiviral therapy in hepatitis C patients: a comparison of IFN-free versus IFN-based regimens at an individual patient level in Australia

    Directory of Open Access Journals (Sweden)

    Lee AS

    2017-10-01

    Full Text Available Allister Sebastian Lee,1 Mieke L van Driel,2 Darrell HG Crawford3,4 1Faculty of Medicine, 2Primary Care Clinical Unit, Faculty of Medicine, 3School of Clinical Medicine, Faculty of Medicine, University of Queensland, 4Gallipoli Medical Research Foundation, Greenslopes Private Hospital, Brisbane, Australia Background: Chronic hepatitis C remains a major global health burden with serious long-term consequences if left untreated. Recently the treatment standard of care has shifted to new interferon (IFN-free drug regimens, which have been shown to be safe and effective. The aim of our study was to assess and compare medical resource utilization and costs of successfully treating patients with IFN-based and IFN-free therapies in Australia. Methods: We performed a retrospective chart review of 30 HCV-infected patients successfully treated with IFN-based therapy between 2013 and 2015. We also generated a model for a virtual group of 100 genotype 1 (GT1 and 100 genotype 3 (GT3 patients treated with IFN-free therapy derived from national guidelines and clinical trial data. Results: In comparison to virtual patients receiving IFN-free therapy, our IFN-treated patients on average had distinctively more liver clinic visits and blood tests. However, mean total cost per patient was $19,164 and $85,300 (AUD more for GT1 and GT3 patients receiving IFN-free therapy, respectively. This difference was largely accounted for by higher antiviral drug costs. Of our 30 patients treated with IFN, total mean cost per patient during the study period was $33,595. Conclusion: Resource utilization is lower with IFN-free treatment, which reflects the reduced need for patient monitoring and improved side-effect profile of these new drugs. However, total costs are still largely dominated by antiviral drug costs, representing a huge burden on national budgets. Our insight into resource utilization and costs associated with both types of treatment can serve as a reference for

  2. Exosomes mediate hepatitis B virus (HBV) transmission and NK-cell dysfunction

    Science.gov (United States)

    Yang, Yinli; Han, Qiuju; Hou, Zhaohua; Zhang, Cai; Tian, Zhigang; Zhang, Jian

    2017-01-01

    Evidence suggests that exosomes can transfer genetic material between cells. However, their roles in hepatitis B virus (HBV) infection remain unclear. Here, we report that exosomes present in the sera of chronic hepatitis B (CHB) patients contained both HBV nucleic acids and HBV proteins, and transferred HBV to hepatocytes in an active manner. Notably, HBV nucleic acids were detected in natural killer (NK) cells from both CHB patients and healthy donors after exposure to HBV-positive exosomes. Through real-time fluorescence microscopy and flow cytometry, 1,1'-dioctadecyl-3,3,3',3',-tetramethylindodicarbocyanine, 4-chlorobenzenesulfnate salt (DiD)-labeled exosomes were observed to interact with NK cells and to be taken up by NK cells, which was enhanced by transforming growth factor-β treatment. Furthermore, HBV-positive exosomes impaired NK-cell functions, including interferon (IFN)-γ production, cytolytic activity, NK-cell proliferation and survival, as well as the responsiveness of the cells to poly (I:C) stimulation. HBV infection suppressed the expression of pattern-recognition receptors, especially retinoic acid inducible gene I (RIG-I), on NK cells, resulting in the dampening of the nuclear factor κB(NF-κB) and p38 mitogen-activated protein kinase pathways. Our results highlight a previously unappreciated role of exosomes in HBV transmission and NK-cell dysfunction during CHB infection. PMID:27238466

  3. Biomodulation with sequential intravenous IFN-alpha2b and 5-fluorouracil as second-line treatment in patients with advanced colorectal cancer.

    Science.gov (United States)

    Pérez, J E; Lacava, J A; Domínguez, M E; Rodríguez, R; Barbieri, M R; Romero Acuña, L A; Romero Acuña, J M; Langhi, M J; Amato, S; Marrone, N; Ortiz, E H; Leone, B A; Vallejo, C T; Machiavelli, M R; Romero, A O

    1998-08-01

    A phase II trial was carried out by the Grupo Oncologico Cooperativo del Sur (G.O.C.S.) to assess the efficacy and toxicity of a biochemical modulation of 5-fluorouracil (5-FU) by i.v. pretreatment with interferon (IFN)-alpha2b in patients with advanced colorectal carcinoma refractory to previous therapy with 5-FU modulated by methotrexate (MTX) or leucovorin (LV) or both. Between January 1993 and October 1995, 34 patients were entered on the study. The treatment was IFN-alpha2b 5 x 10(6)/m2 IU in a 1-h i.v. infusion, followed immediately by 5-FU 600 mg/m2 i.v. bolus injection. Courses were repeated weekly until observation of progressive disease or severe toxicity. One patient could not be assessed for response. Objective regression was observed in 2 of 33 patients (6%, 95% confidence interval, 0%-14%). No patient achieved a complete response. Two patients had partial responses (6%). No change was recorded in 14 patients (41%), and progressive disease occurred in 17 (52%). The median time to treatment failure was 3 months, and the median survival was 5 months. Toxicity was within acceptable limits. The main side effects were mucositis and diarrhea. Four episodes of grade 2 stomatitis were observed, causing dosage modifications. The most frequent toxic effects attributable to IFN-alpha2b were mild fatigue and fever. In conclusion, second-line therapy with i.v. IFN-alpha2b preceding 5-FU has shown an interesting profile of activity in a patient population with clearly unfavorable characteristics. From this perspective, further appropriately designed studies are needed to identify the greatest potential of IFN-alpha2b as a modulator of 5-FU.

  4. Modelling and simulation of dynamic wheel-rail interaction using a roller rig

    International Nuclear Information System (INIS)

    Anyakwo, A; Pislaru, C; Ball, A; Gu, F

    2012-01-01

    The interaction between the wheel and rail greatly influences the dynamic response of railway vehicles on the track. A roller rig facility can be used to study and monitor real time parameters that influence wheel-rail interaction such as wear, adhesion, friction and corrugation without actual field tests being carried out. This paper presents the development of the mathematical models for full scale roller rig and 1/5 scale roller rig and the wear prediction model based on KTH wear function. The simulated critical speed for the 1/5 scale roller rig is about one-fifth of the critical speed for the full scale model so the simulated results compare well with the theory related to wheel-rail contact and dynamics. Also the differences between the simulated rolling radii for the full scale model with and without wear function are analysed. This paper presents the initial stage of a large scale research project where the influence of wear on the wheel-rail performance will be studied in more depth.

  5. RIG-1 expression is associated with sexual malfunctions of female type 2 diabetic patients

    Directory of Open Access Journals (Sweden)

    Batool Hajebrahimi

    2017-03-01

    Full Text Available Introduction: The patients with type 2 diabetes (T2D suffer from the malfunctions of the sexual behaviors, and several mechanisms have been proposed to describe these disorders. The innate immunity may be involved in the malfunctions of T2D patients. Melanoma differentiation-associated protein 5 (MDA5 and retinoic acid (RA-inducible gene 1 (RIG-1, as the innate immunity receptors, are the responsible molecules for the activation of some intracellular signaling pathways and the induction of inflammation. Thus, this study aimed to examine the molecules which may participate in the induction/stimulation of sexual malfunctions in the female T2D patients. Methods: Sexual functions were evaluated in 41 female T2D patients using the Female Sexual Function Index (FSFI questionnaire. Real-time polymerase chain reaction (PCR technique was used to quantify MDA5 and RIG-1 mRNA levels. Results: Results showed that increased RIG-1 mRNA levels were significantly associated with the bad orgasm in the female T2D patients compared to the female patients with good orgasm. Expression of RIG-1 and MDA5 levels were not associated with other sexual functions’ criteria. Conclusion: The findings of this study demonstrated that bad orgasm is associated with the increased RIG-1 expression. Consequently, the correlation between inflammation and bad orgasm in a RIG-1 dependent manner is suggested.

  6. MicroRNA-Attenuated Clone of Virulent Semliki Forest Virus Overcomes Antiviral Type I Interferon in Resistant Mouse CT-2A Glioma.

    Science.gov (United States)

    Martikainen, Miika; Niittykoski, Minna; von und zu Fraunberg, Mikael; Immonen, Arto; Koponen, Susanna; van Geenen, Maartje; Vähä-Koskela, Markus; Ylösmäki, Erkko; Jääskeläinen, Juha E; Saksela, Kalle; Hinkkanen, Ari

    2015-10-01

    Glioblastoma is a terminal disease with no effective treatment currently available. Among the new therapy candidates are oncolytic viruses capable of selectively replicating in cancer cells, causing tumor lysis and inducing adaptive immune responses against the tumor. However, tumor antiviral responses, primarily mediated by type I interferon (IFN-I), remain a key problem that severely restricts viral replication and oncolysis. We show here that the Semliki Forest virus (SFV) strain SFV4, which causes lethal encephalitis in mice, is able to infect and replicate independent of the IFN-I defense in mouse glioblastoma cells and cell lines originating from primary human glioblastoma patient samples. The ability to tolerate IFN-I was retained in SFV4-miRT124 cells, a derivative cell line of strain SFV4 with a restricted capacity to replicate in neurons due to insertion of target sites for neuronal microRNA 124. The IFN-I tolerance was associated with the viral nsp3-nsp4 gene region and distinct from the genetic loci responsible for SFV neurovirulence. In contrast to the naturally attenuated strain SFV A7(74) and its derivatives, SFV4-miRT124 displayed increased oncolytic potency in CT-2A murine astrocytoma cells and in the human glioblastoma cell lines pretreated with IFN-I. Followi