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Sample records for anti-influenza virus activity

  1. Anti-Influenza Virus Activity and Constituents Characterization of Paeonia delavayi Extracts

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    Jinhua Li

    2016-08-01

    Full Text Available Paeonia delavayi, an endemic species in southwestern China, has been widely used as a traditional remedy for cardiovascular, extravasated blood, stagnated blood and female diseases in traditional Chinese medicine (TCM. However, there are no reports on the anti-influenza virus activity of this species. Here, the anti-influenza virus activity of P. delavayi root extracts was first evaluated by an influenza virus neuraminidase (NA inhibition assay. Meantime, constituents in the active extracts were identified using ultra-high performance liquid coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS and seven major identified constituents were used to further evaluate the NA inhibitory activity. The results showed that the ethyl acetate fraction (EA and the ethanol fraction (E of P. delavayi both presented strong NA inhibitory activity with IC50 values of 75.932 μg/mL and 83.550 μg/mL, respectively. Twenty-seven constituents were characterized in these two active extracts by UPLC-Q-TOF-MS analysis, and seven major identified constituents exhibited high activity against the influenza virus. Among them, Benzoylpaeoniflorin (IC50 = 143.701 µM and pentagalloylglucose (IC50 = 62.671 µM exhibited the highest activity against the influenza virus, even far stronger than oseltamivir acid (IC50 = 281.308 µM. This study indicated that P. delavayi was a strong NA inhibitor, but cell-based inhibition, anti-influenza virus activity in vivo and anti-influenza virus mechanism still need to be tested and explored.

  2. Pyrazole compound BPR1P0034 with potent and selective anti-influenza virus activity

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    Yeh Jiann-Yih

    2010-02-01

    Full Text Available Abstract Background Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1 virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals. Methods We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle. Results The 50% effective inhibitory concentration (IC50 of BPR1P0034 was 0.42 ± 0.11 μM, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1 was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption, its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest

  3. "On-Water" Facile Synthesis of Novel Pyrazolo[3,4-b]pyridinones Possessing Anti-influenza Virus Activity.

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    Zeng, Li-Yan; Liu, Teng; Yang, Jie; Yang, Yueli; Cai, Chun; Liu, Shuwen

    2017-07-10

    A facile and versatile "on-water" protocol for the synthesis of pyrazolo[3,4-b]pyridinones was developed by the unprecedented construction of two rings and five new bonds in one-pot. It was proved that water was an important promoter of the reaction and PEG2000 was found to improve the reaction in terms of yield. 32 Derivatives were newly synthesized and most of them were prepared in an hour. The scope and limitation indicated that electron withdrawing groups substituted on synthons, substituted benzoyl acetonitriles or aryl aldehydes, were helpful to construct the pyrazolo[3,4-b]pyridinones. The reaction media PEG2000/H 2 O was successfully recycled and reused at least 5 times without any obvious decrease in yield. The anti-influenza activities of the derivatives were evaluated and the screening results highlighted two derivatives, which exhibited strong inhibitory activity against H5N1 pseudovirus. These positive bioassay results implied that the library of potential anti-influenza virus agent candidates could be rapidly prepared in an eco-friendly manner, and provided a new insight into drug discovery for medicinal chemists.

  4. Bioactivity-guided fractionation and analysis of compounds with anti-influenza virus activity from Gardenia jasminoides Ellis.

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    Yang, Quanjun; Wu, Bin; Shi, Yujing; Du, Xiaowei; Fan, Mingsong; Sun, Zhaolin; Cui, Xiaolan; Huang, Chenggang

    2012-01-01

    Bioassay-guided fractionation of extracts from Fructus Gardeniae led to analysis of its bioactive natural products. After infection by influenza virus strain A/FM/1/47-MA in vivo, antiviral activity of the extracts were investigated. The target fraction was orally administered to rats and blood was collected. High-performance liquid chromatography coupled with photo diode array detector and electrospray ion trap multiple-stage tandem mass spectrometry was applied to screen the compounds absorbed into the blood. A structural characterization based on the retention time, ultraviolet spectra, parent ions and fragmentation ions was performed. Thirteen compounds were confirmed or tentatively identified. This provides an accurate profile of the composition of bioactive compounds responsible for the anti-influenza properties.

  5. Structure and anti-influenza A (H1N1) virus activity of three polysaccharides from Eucheuma denticulatum

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    Yu, Guangli; Li, Miaomiao; Wang, Wei; Liu, Xin; Zhao, Xiaoliang; Lv, Youjing; Li, Guangsheng; Jiao, Guangling; Zhao, Xia

    2012-12-01

    Three polysaccharides (EW, EH and EA) were prepared from a red alga Eucheuma denticulatum by sequential extraction with cold water, hot water and sodium hydroxide water solution. Their monosaccharide compositions, relative molecular mass and structural characterization were determined by gas chromatography, high performance 1iquid chromatography, fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy methods. EW was hybrid ı/κ/ν-carrageenan (70 ı/17κ/13ν-carrabiose), EH was mainly ı-carrageenan, and EA was mainly α-1,4-Glucan (88%) but mixed with small amount of ı-carrageenan (12%). The relative molecular mass of EW, EH and EA was 480, 580 and 510 kDa, respectively. The anti-influenza A (H1N1) virus activity of these three polysaccharides was evaluated using the Madin-Darby canine kidney cells model. EW showed good anti-H1N1 virus activity, its IC50 was 276.5 μg mL-1, and the inhibition rate to H1N1 virus was 52% when its concentration was 250 μg mL-1. The IC50 of ı-carrageenan EH was 366.4 μg mL-1, whereas EA showed lower anti-H1N1 virus activity (IC50>430 μg mL-1). Available data obtained give positive evidence that the hybrid carrageenan EW from Eucheuma denticulatum can be used as potential anti-H1N1 virus inhibitor in future.

  6. Anti-influenza A virus activity of rhein through regulating oxidative stress, TLR4, Akt, MAPK, and NF-κB signal pathways.

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    Qian-Wen Wang

    Full Text Available Rhein, an anthraquinone compound existing in many traditional herbal medicines, has anti-inflammatory, antioxidant, antitumor, antiviral, hepatoprotective, and nephroprotective activities, but its anti-influenza A virus (IAV activity is ambiguous. In the present study, through plaque inhibition assay, time-of-addition assay, antioxidant assay, qRT-PCR, ELISA, and western blotting assays, we investigated the anti-IAV effect and mechanism of action of rhein in vitro and in vivo. The results showed that rhein could significantly inhibit IAV adsorption and replication, decrease IAV-induced oxidative stress, activations of TLR4, Akt, p38, JNK MAPK, and NF-κB pathways, and production of inflammatory cytokines and matrix metalloproteinases in vitro. Oxidant H2O2 and agonists of TLR4, Akt, p38/JNK and IKK/NF-κB could significantly antagonize the inhibitory effects of rhein on IAV-induced cytopathic effect (CPE and IAV replication. Through an in vivo test in mice, we also found that rhein could significantly improve the survival rate, lung index, pulmonary cytokines, and pulmonary histopathological changes. Rhein also significantly decreased pulmonary viral load at a high dose. In conclusion, rhein can inhibit IAV adsorption and replication, and the mechanism of action to inhibit IAV replication may be due to its ability to suppress IAV-induced oxidative stress and activations of TLR4, Akt, p38, JNK MAPK, and NF-κB signal pathways.

  7. Anti-influenza activity of marchantins, macrocyclic bisbibenzyls contained in liverworts.

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    Yuma Iwai

    Full Text Available The H1N1 influenza A virus of swine-origin caused pandemics throughout the world in 2009 and the highly pathogenic H5N1 avian influenza virus has also caused epidemics in Southeast Asia in recent years. The threat of influenza A thus remains a serious global health issue and novel drugs that target these viruses are highly desirable. Influenza A possesses an endonuclease within its RNA polymerase which comprises PA, PB1 and PB2 subunits. To identify potential new anti-influenza compounds in our current study, we screened 33 different types of phytochemicals using a PA endonuclease inhibition assay in vitro and an anti-influenza A virus assay. The marchantins are macrocyclic bisbibenzyls found in liverworts, and plagiochin A and perrottetin F are marchantin-related phytochemicals. We found from our screen that marchantin A, B, E, plagiochin A and perrottetin F inhibit influenza PA endonuclease activity in vitro. These compounds have a 3,4-dihydroxyphenethyl group in common, indicating the importance of this moiety for the inhibition of PA endonuclease. Docking simulations of marchantin E with PA endonuclease suggest a putative "fitting and chelating model" as the mechanism underlying PA endonuclease inhibition. The docking amino acids are well conserved between influenza A and B. In a cultured cell system, marchantin E was further found to inhibit the growth of both H3N2 and H1N1 influenza A viruses, and marchantin A, E and perrotein F showed inhibitory properties towards the growth of influenza B. These marchantins also decreased the viral infectivity titer, with marchantin E showing the strongest activity in this assay. We additionally identified a chemical group that is conserved among different anti-influenza chemicals including marchantins, green tea catechins and dihydroxy phenethylphenylphthalimides. Our present results indicate that marchantins are candidate anti-influenza drugs and demonstrate the utility of the PA endonuclease assay in

  8. Targeting organic anion transporter 3 with probenecid as a novel anti-influenza a virus strategy.

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    Perwitasari, Olivia; Yan, Xiuzhen; Johnson, Scott; White, Caleb; Brooks, Paula; Tompkins, S Mark; Tripp, Ralph A

    2013-01-01

    Influenza A virus infection is a major global health concern causing significant mortality, morbidity, and economic loss. Antiviral chemotherapeutics that target influenza A virus are available; however, rapid emergence of drug-resistant strains has been reported. Consequently, there is a burgeoning need to identify novel anti-influenza A drugs, particularly those that target host gene products required for virus replication, to reduce the likelihood of drug resistance. In this study, a small interfering RNA (siRNA) screen was performed to identify host druggable gene targets for anti-influenza A virus therapy. The host organic anion transporter-3 gene (OAT3), a member of the SLC22 family of transporters, was validated as being required to support influenza A virus replication. Probenecid, a prototypical uricosuric agent and chemical inhibitor of organic anion transporters known to target OAT3, was shown to be effective in limiting influenza A virus infection in vitro (50% inhibitory concentration [IC(50)] of 5.0 × 10(-5) to 5.0 × 10(-4) μM; P Probenecid is widely used for treatment of gout and related hyperuricemic disorders, has been extensively studied for pharmacokinetics and safety, and represents an excellent candidate for drug repositioning as a novel anti-influenza A chemotherapeutic.

  9. Fibroblast activation protein is dispensable in the anti-influenza immune response in mice.

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    Sioh-Yang Tan

    Full Text Available Fibroblast activation protein alpha (FAP is a unique dual peptidase of the S9B serine protease family, being capable of both dipeptidyl peptidase and endopeptidase activities. FAP is expressed at low level in healthy adult organs including the pancreas, cervix, uterus, submaxillary gland and the skin, and highly upregulated in embryogenesis, chronic inflammation and tissue remodelling. It is also expressed by cancer-associated stromal fibroblasts in more than 90% of epithelial tumours. FAP has enzymatic and non-enzymatic functions in the growth, immunosuppression, invasion and cell signalling of tumour cells. FAP deficient mice are fertile and viable with no gross abnormality, but little data exist on the role of FAP in the immune system. FAP is upregulated in association with microbial stimulation and chronic inflammation, but its function in infection remains unknown. We showed that major populations of immune cells including CD4+ and CD8+ T cells, B cells, dendritic cells and neutrophils are generated and maintained normally in FAP knockout mice. Upon intranasal challenge with influenza virus, FAP mRNA was increased in the lungs and lung-draining lymph nodes. Nonetheless, FAP deficient mice showed similar pathologic kinetics to wildtype controls, and were capable of supporting normal anti-influenza T and B cell responses. There was no evidence of compensatory upregulation of other DPP4 family members in influenza-infected FAP-deficient mice. FAP appears to be dispensable in anti-influenza adaptive immunity.

  10. [Screening based on response surface methodology of multi-fractions traditional Chinese medicine with anti-influenza virus neuraminidase activity: take shuanghuanglian injection as an example].

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    Qiu, Ling-Ling; Chen, Long-Hu; Yan, Dan; Zhang, Ping; Tan, Man-Rong; Li, Zheng-Ming; Xiao, Xiao-He

    2012-04-01

    This study aimed to establish a novel method to screen out the combined components of multi-fractions traditional Chinese medicine (TCM), so that the internal relationship between multi-ingredients could be objectively assessed and the proportioning ratio could be optimized. Taking antiviral effect on neuraminidase activity of influenza virus as the evaluating indicator and using Box-Behnken response surface methodology, the main effective ingredients of Shuanghuanglian injection (SHL) were screened. Meanwhile, the relationship between active ingredients was discussed. Taking SHL as a comparison, the optimum proportioning ratio was predicted. The results indicated that chlorogenic acid, cryptochlorogenic acid, caffeic acid and baicalin have comparatively strong antiviral activity against influenza virus. Moreover, antagonistic action existed between chlorogenic acid and cryptochlorogenic acid, whereas synergistic action between caffeic acid and other components. The optimum proportioning ratio resulted from fitted model is: chlorogenic acid, cryptochlorogenic acid, caffeic acid and baicalin (107 microg x mL(-1) : 279 microg x mL(-1) : 7.99 microg x mL(-1) : 92 microg x mL(-1)). The antiviral activity of the recombined components is stronger than that of SHL, which was consistent with the experiment results (P < 0.05). Box-Behnken response surface methodology has the advantages of general-screening, high-performance and accurate-prediction etc, which is appropriate for screening the combined components of multi-fractions TCM and the optimization of the proportioning ratio. The proposed method can serve as a technological support for the development of modern multi-fractions TCM.

  11. Characterization of the Anti-Influenza Activity of the Chinese Herbal Plant Paeonia lactiflora

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    Jin-Yuan Ho

    2014-04-01

    Full Text Available Bai Shao (BS, the root of Paeonia lactiflora Pall., a common Chinese herb in many recipes used to treat viral infection and liver diseases, is recognized for its ability to nourish menstruation, its Yin convergence, and as an antiperspirant. However, the mechanism and components for its antiviral function remain to be elucidated. In this study, an ethanolic extract of BS was further partitioned into aqueous and organic parts (EAex for in vitro functional study and in vivo efficacy testing. EAex exhibited an IC50 of 0.016 ± 0.005 mg/mL against influenza virus A/WSN/33 (H1N1, with broad-spectrum inhibitory activity against different strains of human influenza A viruses, including clinical oseltamivir-resistant isolates and an H1N1pdm strain. The synthesis of both viral RNA and protein was profoundly inhibited when the cells were treated with EAex. A time-of-addition assay demonstrated that EAex exerted its antiviral activity at various stages of the virus replication cycle. We addressed its antiviral activity at virus entry and demonstrated that EAex inhibits viral hemagglutination and viral binding to and penetration into host cells. In vivo animal testing showed that 200 mg/kg/d of EAex offered significant protection against viral infection. We conclude that BS possesses antiviral activity and has the potential for development as an anti-influenza agent.

  12. Properties of polysaccharides in several seaweeds from Atlantic Canada and their potential anti-influenza viral activities

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    Jiao, Guangling; Yu, Guangli; Wang, Wei; Zhao, Xiaoliang; Zhang, Junzeng; Ewart, Stephen H.

    2012-06-01

    To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae ( Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae ( Ascophyllum nodosum and Fucus vesiculosus), and one green alga ( Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were analyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties.

  13. Identification of traditional medicinal plant extracts with novel anti-influenza activity.

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    Dhivya Rajasekaran

    Full Text Available The emergence of drug resistant variants of the influenza virus has led to a need to identify novel and effective antiviral agents. As an alternative to synthetic drugs, the consolidation of empirical knowledge with ethnopharmacological evidence of medicinal plants offers a novel platform for the development of antiviral drugs. The aim of this study was to identify plant extracts with proven activity against the influenza virus. Extracts of fifty medicinal plants, originating from the tropical rainforests of Borneo used as herbal medicines by traditional healers to treat flu-like symptoms, were tested against the H1N1 and H3N1 subtypes of the virus. In the initial phase, in vitro micro-inhibition assays along with cytotoxicity screening were performed on MDCK cells. Most plant extracts were found to be minimally cytotoxic, indicating that the compounds linked to an ethnomedical framework were relatively innocuous, and eleven crude extracts exhibited viral inhibition against both the strains. All extracts inhibited the enzymatic activity of viral neuraminidase and four extracts were also shown to act through the hemagglutination inhibition (HI pathway. Moreover, the samples that acted through both HI and neuraminidase inhibition (NI evidenced more than 90% reduction in virus adsorption and penetration, thereby indicating potent action in the early stages of viral replication. Concurrent studies involving Receptor Destroying Enzyme treatments of HI extracts indicated the presence of sialic acid-like component(s that could be responsible for hemagglutination inhibition. The manifestation of both modes of viral inhibition in a single extract suggests that there may be a synergistic effect implicating more than one active component. Overall, our results provide substantive support for the use of Borneo traditional plants as promising sources of novel anti-influenza drug candidates. Furthermore, the pathways involving inhibition of hemagglutination

  14. A natural component from Euphorbia humifusa Willd displays novel, broad-spectrum anti-influenza activity by blocking nuclear export of viral ribonucleoprotein

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    Chang, So Young; Park, Ji Hoon [Respiratory Viruses Research Laboratory, Discovery Biology Department, Institut Pasteur Korea, 16, Daewangpangyo-ro 712 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 463-400 (Korea, Republic of); Kim, Young Ho; Kang, Jong Seong [College of Pharmacy, Chungnam National University, Daejeon, 305-764 (Korea, Republic of); Min, Ji-Young, E-mail: jiyoung.min@ip-korea.org [Respiratory Viruses Research Laboratory, Discovery Biology Department, Institut Pasteur Korea, 16, Daewangpangyo-ro 712 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 463-400 (Korea, Republic of)

    2016-03-04

    The need to develop anti-influenza drugs with novel antiviral mechanisms is urgent because of the rapid rate of antigenic mutation and the emergence of drug-resistant viruses. We identified a novel anti-influenza molecule by screening 861 plant-derived natural components using a high-throughput image-based assay that measures inhibition of the influenza virus infection. 1,3,4,6-tetra-O-galloyl-β-D-glucopyranoside (TGBG) from Euphorbia humifusa Willd showed broad-spectrum anti-influenza activity against two seasonal influenza A strains, A/California/07/2009 (H1N1) and A/Perth/16/2009 (H3N2), and seasonal influenza B strain B/Florida/04/2006. We investigated the mode of action of TGBG using neuraminidase activity inhibition and time-of-addition assays, which evaluate the viral release and entry steps, respectively. We found that TGBG exhibits a novel antiviral mechanism that differs from the FDA-approved anti-influenza drugs oseltamivir which inhibits viral release, and amantadine which inhibits viral entry. Immunofluorescence assay demonstrated that TGBG significantly inhibits nuclear export of influenza nucleoproteins (NP) during the early stages of infection causing NP to accumulate in the nucleus. In addition, influenza-induced activation of the Akt signaling pathway was suppressed by TGBG in a dose-dependent manner. These data suggest that a putative mode of action of TGBG involves inhibition of viral ribonucleoprotein (vRNP) export from the nucleus to the cytoplasm consequently disrupting the assembly of progeny virions. In summary, TGBG has potential as novel anti-influenza therapeutic with a novel mechanism of action. - Highlights: • The plant-derived natural product TGBG has broad-spectrum antiviral activity against seasonal influenza A and B viruses. • TGBG has a novel anti-viral mechanism of action that from differs from the currently available anti-influenza drugs. • TGBG hinders nuclear export of the influenza virus ribonucleoprotein (v

  15. Promising Anti-influenza Properties of Active Constituent of Withania somnifera Ayurvedic Herb in Targeting Neuraminidase of H1N1 Influenza: Computational Study.

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    Cai, Zhi; Zhang, Guoyin; Tang, Bin; Liu, Yan; Fu, Xiaojing; Zhang, Xuejin

    2015-07-01

    Neuraminidase (NA) is a membrane surface antigen which helps in the release of influenza viruses from the host cells after replication. Anti-influenza drugs such as zanamivir bind with eight highly conserved functional residues (R118, D151, R152, R224, E276, R292, R371, and Y406) in the active site of NA, thus restricting the viral release the from host cells. Binding of the drug in active site inhibits the ability of enzyme to cleave sialic acid residues on the cell membrane. Reports on the emergence of zanamivir-resistant strains of H1N1 Influenza virus necessitated a search for alternative drug candidates, preferably from plant source due to their known benefits such as less or no side effects, availability, and low cost. Withaferin A (WA), an active constituent of Withania somnifera ayurvedic herb, has been shown to have a broad range of medicinal properties including its anti-viral activity. The present study demonstrated that WA has the potential to attenuate the neuraminidase of H1N1 influenza. Our docking and simulation results predicted high binding affinity of the WA toward NA and revealed several interesting molecular interactions with the residues which are catalytically important during molecular dynamic simulations. The results presented in the article could be of high importance for further designing of target-specific anti-influenza drug candidates.

  16. Influenza A virus infection in zebrafish recapitulates mammalian infection and sensitivity to anti-influenza drug treatment

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    Kristin A. Gabor

    2014-11-01

    Full Text Available Seasonal influenza virus infections cause annual epidemics and sporadic pandemics. These present a global health concern, resulting in substantial morbidity, mortality and economic burdens. Prevention and treatment of influenza illness is difficult due to the high mutation rate of the virus, the emergence of new virus strains and increasing antiviral resistance. Animal models of influenza infection are crucial to our gaining a better understanding of the pathogenesis of and host response to influenza infection, and for screening antiviral compounds. However, the current animal models used for influenza research are not amenable to visualization of host-pathogen interactions or high-throughput drug screening. The zebrafish is widely recognized as a valuable model system for infectious disease research and therapeutic drug testing. Here, we describe a zebrafish model for human influenza A virus (IAV infection and show that zebrafish embryos are susceptible to challenge with both influenza A strains APR8 and X-31 (Aichi. Influenza-infected zebrafish show an increase in viral burden and mortality over time. The expression of innate antiviral genes, the gross pathology and the histopathology in infected zebrafish recapitulate clinical symptoms of influenza infections in humans. This is the first time that zebrafish embryos have been infected with a fluorescent IAV in order to visualize infection in a live vertebrate host, revealing a pattern of vascular endothelial infection. Treatment of infected zebrafish with a known anti-influenza compound, Zanamivir, reduced mortality and the expression of a fluorescent viral gene product, demonstrating the validity of this model to screen for potential antiviral drugs. The zebrafish model system has provided invaluable insights into host-pathogen interactions for a range of infectious diseases. Here, we demonstrate a novel use of this species for IAV research. This model has great potential to advance our

  17. Genotypes of Pestivirus RNA detected n anti influenza virus vaccines for human use

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    M. Giangaspero

    2004-02-01

    Full Text Available Nine polyvalent human influenza virus vaccines were tested by reverse transcriptase-polymerase chain reaction (RT-PCR for the presence of pestivirus RNA. Samples were selected from manufacturers in Europe and the USA. Three samples of the nine vaccines tested (33.3% gave positive results for pestivirus RNA. The 5´-untranslated genomic region sequence of the contaminant pestivirus RNA was analysed based on primary nucleotide sequence homology and on secondary sequence structures characteristic to genotypes. Two sequences belonged to Pestivirus type-1 (bovine viral diarrhoea virus [BVDV] species, genotypes BVDV-1b and BVDV-1e. These findings confirm previous reports, suggesting an improvement in preventive measures against contamination of biological products for human use.

  18. Anti-influenza activity in the Indian seaweeds - A preliminary investigation

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    Chatterji, A.; Dhargalkar, V.K.; Sreekumar, P.K.; Parameswaran, P.S.; Rodrigues, R.; Kotnala, S.

    -allantonic membrane (CAM) of chicken eggs infected with influenza virus strains A/Mississippi/1/85 and B/Jamanashi/1/166/95 for in vitro studies. The reduction of infection was low against virus strain A/Mississippi/1/85 where maximum reduction was 45...

  19. In vitro evaluation of the antiviral activity of methylglyoxal against influenza B virus infection.

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    Charyasriwong, Siriwan; Haruyama, Takahiro; Kobayashi, Nobuyuki

    Influenza A and B virus infections are serious public health concerns globally. However, the concerns regarding influenza B infection have been underestimated. The currently used anti-influenza drugs have not provided equal efficacy for both influenza A and B viruses. Susceptibility to neuraminidase (NA) inhibitors has been observed to be lower for influenza B viruses than for influenza A viruses. Moreover, the emergence of resistance to anti-influenza drugs underscores the need to develop new drugs. Recently, we reported that methylglyoxal (MGO) suppressed influenza A virus replication in a strain-independent manner. Therefore, we hypothesize that MGO exhibits anti-influenza activity against B strains. This study aimed to evaluate the anti-influenza viral activity of MGO against influenza B strains by using Madin-Darby canine kidney (MDCK) cells. Several types of influenza B viruses were used to determine the activity of MGO. The susceptibilities of influenza A and B viruses to NA inhibitors were compared. MGO inhibited influenza B virus replication, with 50% inhibitory concentrations ranging from 23-140 μM, which indicated greater sensitivity of influenza B viruses than influenza A viruses. Our results show that MGO has potent inhibitory activity against influenza B viruses, including NA inhibitor-resistant strains.

  20. [Antibody response to trivalent anti-influenza vaccination (inactivated virus) A/Texas/1/77 H3N2), A/URSS/90/77 (H1N1), B/Hong Kong/8/73].

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    Mancini, G; Andreoni, M; Arangio-Ruiz, G; Sarrecchia, C; Donatelli, I; Resta, S; Rozera, C; Sordillo, P; Rocchi, G

    1982-05-01

    Seventy-five young recruits received an intramuscular dose of anti-influenza virus vaccine containing 300 U.I. of A/Texas/1/77 (H3N2), A/URSS/90/77 (H1N1), B/Hong Kong/8/73 strains. Antibody responses were detected by HI and SRH tests: immunogenicity of the preparation was different for the individual vaccine strain in spite of the similar amount of antigenic content, and the immunity conferred by vaccine strains did not significantly extend to new influenza virus strains which prevailed in 1979/80 winter season with the exception for A/Brazil/11/78 (H1N1).

  1. Anti-Influenza Treatment: Drugs Currently Used and Under Development.

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    Amarelle, Luciano; Lecuona, Emilia; Sznajder, Jacob I

    2017-01-01

    Influenza is a very common contagious disease that carries significant morbidity and mortality. Treatment with antiviral drugs is available, which if administered early, can reduce the risk of severe complications. However, many virus types develop resistance to those drugs, leading to a notable loss of efficacy. There has been great interest in the development of new drugs to combat this disease. A wide range of drugs has shown anti-influenza activity, but they are not yet available for use in the clinic. Many of these target viral components, which others are aimed at elements in the host cell which participate in the viral cycle. Modulating host components is a strategy which minimizes the development of resistance, since host components are not subject to the genetic variability of the virus. The main disadvantage is the risk of treatment-related side effects. The aim of this review is to describe the main pharmacological agents currently available and new drugs in the pipeline with potential benefit in the treatment of influenza. Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. T-705 (Favipiravir) suppresses tumor necrosis factor α production in response to influenza virus infection: A beneficial feature of T-705 as an anti-influenza drug.

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    Tanaka, T; Kamiyama, T; Daikoku, T; Takahashi, K; Nomura, N; Kurokawa, M; Shiraki, K

    Influenza virus infection induces the production of various cytokines, which play important roles in the pathogenesis of infection. Among the cytokines induced by influenza, tumor necrosis factor α (TNF-α) production has been correlated with the severity of lung lesions. We investigated the effects of T-705 (Favipiravir, 6-fluoro-3-hydroxy-2-pyrazinecarboxamide) on cytokine production due to influenza virus infection in vitro and in vivo, compared with oseltamivir or GS 4071, an active form of oseltamivir. TNF-α production in mouse macrophage-derived P388D1 cells infected with the influenza virus was lower following treatment with T-705 at concentrations of 0.3 to 100 µg/ml than treatment with GS 4071 at the same concentrations. The effect of treatment with T-705 on the cytokine production induced by the influenza virus infection was investigated in mouse influenza virus infection model. At 48 h post-infection (p.i.) T-705 significantly suppressed the viral load in the lungs and TNF-α production in the airways of infected mice even when viral loads were high. Furthermore, T-705 suppressed only TNF-α production from the early phase of infection. In this study, T-705 showed the antiviral activity of reducing pulmonary viral load compared with oseltamivir, thereby suppressing the TNF-α production. This feature of T-705 is benefit against severe influenza infection.

  3. Analysis of Anti-Influenza Virus Neuraminidase Antibodies in Children, Adults, and the Elderly by ELISA and Enzyme Inhibition: Evidence for Original Antigenic Sin.

    Science.gov (United States)

    Rajendran, Madhusudan; Nachbagauer, Raffael; Ermler, Megan E; Bunduc, Paul; Amanat, Fatima; Izikson, Ruvim; Cox, Manon; Palese, Peter; Eichelberger, Maryna; Krammer, Florian

    2017-03-21

    Antibody responses to influenza virus hemagglutinin provide protection against infection and are well studied. Less is known about the human antibody responses to the second surface glycoprotein, neuraminidase. Here, we assessed human antibody reactivity to a panel of N1, N2, and influenza B virus neuraminidases in different age groups, including children, adults, and the elderly. Using enzyme-linked immunosorbent assays (ELISA), we determined the breadth, magnitude, and isotype distribution of neuraminidase antibody responses to historic, current, and avian strains, as well as to recent isolates to which these individuals have not been exposed. It appears that antibody levels against N1 neuraminidases were lower than those against N2 or B neuraminidases. The anti-neuraminidase antibody levels increased with age and were, in general, highest against strains that circulated during the childhood of the tested individuals, providing evidence for "original antigenic sin." Titers measured by ELISA correlated well with titers measured by the neuraminidase inhibition assays. However, in the case of the 2009 pandemic H1N1 virus, we found evidence of interference from antibodies binding to the conserved stalk domain of the hemagglutinin. In conclusion, we found that antibodies against the neuraminidase differ in magnitude and breadth between subtypes and age groups in the human population. (This study has been registered at ClinicalTrials.gov under registration no. NCT00336453, NCT00539981, and NCT00395174.) IMPORTANCE Anti-neuraminidase antibodies can afford broad protection from influenza virus infection in animal models and humans. However, little is known about the breadth and magnitude of the anti-neuraminidase response in the human population. Here we assessed antibody levels of children, adults, and the elderly against a panel of N1, N2, and type B influenza virus neuraminidases. We demonstrated that antibody levels measured by ELISA correlate well with functional

  4. Analysis of Anti-Influenza Virus Neuraminidase Antibodies in Children, Adults, and the Elderly by ELISA and Enzyme Inhibition: Evidence for Original Antigenic Sin

    Directory of Open Access Journals (Sweden)

    Madhusudan Rajendran

    2017-03-01

    Full Text Available Antibody responses to influenza virus hemagglutinin provide protection against infection and are well studied. Less is known about the human antibody responses to the second surface glycoprotein, neuraminidase. Here, we assessed human antibody reactivity to a panel of N1, N2, and influenza B virus neuraminidases in different age groups, including children, adults, and the elderly. Using enzyme-linked immunosorbent assays (ELISA, we determined the breadth, magnitude, and isotype distribution of neuraminidase antibody responses to historic, current, and avian strains, as well as to recent isolates to which these individuals have not been exposed. It appears that antibody levels against N1 neuraminidases were lower than those against N2 or B neuraminidases. The anti-neuraminidase antibody levels increased with age and were, in general, highest against strains that circulated during the childhood of the tested individuals, providing evidence for “original antigenic sin.” Titers measured by ELISA correlated well with titers measured by the neuraminidase inhibition assays. However, in the case of the 2009 pandemic H1N1 virus, we found evidence of interference from antibodies binding to the conserved stalk domain of the hemagglutinin. In conclusion, we found that antibodies against the neuraminidase differ in magnitude and breadth between subtypes and age groups in the human population. (This study has been registered at ClinicalTrials.gov under registration no. NCT00336453, NCT00539981, and NCT00395174.

  5. Anti-influenza M2e antibody

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, Andrew M.

    2013-04-16

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  6. Anti-influenza M2e antibody

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, Andrew M [Santa Fe, NM

    2011-12-20

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  7. [Development of the anti-influenza H5N1 vaccines worldwide and in Russia].

    Science.gov (United States)

    Kiselev, O I; Tsybalova, L M; Pokrovskiĭ, V I

    2006-01-01

    Article is dedicated to analytical investigation of the problem of current technologies in construction and manufacturing of anti-influenza vaccines. Epidemiological events in July-November 2005 in Russia (mainly in Siberia) and later in Ukraine showed that Health Care system was not ready for that turn over of epidemiological situation. It was completely the same situation in other countries. There are two general questions of a readiness in pre-pandemic situation: level of a diagnostic monitoring of epidemiological situation and preparedness to fast production of actual vaccine preparations. First task can be solved by immediate production of diagnostic sets for regional branches of National WHO Centers, and a second one depends on application of a novel approaches in construction of a anti-influenza vaccines. The construction of anti-influenza vaccines is based on genetic engineering (reverse genetics) and manipulation with plasmids carried out basic viral genes. Reassortation technology for preparation of hybrid viruses is going to the past by objective reasons. Advanced technologies are safety in laboratories and in manufacturing facilities. Moreover, genetic engineering in this field allows to planing the construction of vaccines bank, when the prognoses for actual viruses include more then two strains with different antigenic properties.

  8. Detection of peramivir and laninamivir, new anti-influenza drugs, in sewage effluent and river waters in Japan.

    Directory of Open Access Journals (Sweden)

    Takashi Azuma

    Full Text Available This is the first report of the detection of two new anti-influenza drugs, peramivir (PER and laninamivir (LAN, in Japanese sewage effluent and river waters. Over about 1 year from October 2013 to July 2014, including the influenza prevalence season in January and February 2014, we monitored for five anti-influenza drugs-oseltamivir (OS, oseltamivir carboxylate (OC, zanamivir (ZAN, PER, and LAN-in river waters and in sewage effluent flowing into urban rivers of the Yodo River system in Japan. The dynamic profiles of these anti-influenza drugs were synchronized well with that of the numbers of influenza patients treated with the drugs. The highest levels in sewage effluents and river waters were, respectively, 82 and 41 ng/L (OS, 347 and 125 ng/L (OC, 110 and 35 ng/L (ZAN, 64 and 11 ng/L (PER, and 21 and 9 ng/L (LAN. However, application of ozone treatment before discharge from sewage treatment plants was effective in reducing the levels of these anti-influenza drugs in effluent. The effectiveness of the ozone treatment and the drug dependent difference in susceptibility against ozone were further evidenced by ozonation of a STP effluent in a batch reactor. These findings should help to promote further environmental risk assessment of the generation of drug-resistant influenza viruses in aquatic environments.

  9. Anti-influenza effect of Cordyceps militaris through immunomodulation in a DBA/2 mouse model.

    Science.gov (United States)

    Lee, Hwan Hee; Park, Heejin; Sung, Gi-Ho; Lee, Kanghyo; Lee, Taeho; Lee, Ilseob; Park, Man-seong; Jung, Yong Woo; Shin, Yu Su; Kang, Hyojeung; Cho, Hyosun

    2014-08-01

    The immune-modulatory as well as anti-influenza effects of Cordyceps extract were investigated using a DBA/2 mouse model. Three different concentrations of Cordyceps extract, red ginseng extract, or drinking water were orally administered to mice for seven days, and then the mice were intranasally infected with 2009 pandemic influenza H1N1 virus. Body weight changes and survival rate were measured daily post-infection. Plasma IL-12, TNF-α, and the frequency of natural killer (NK) cells were measured on day 4 post-infection. The DBA/2 strain was highly susceptible to H1N1 virus infection. We also found that Cordyceps extract had an anti-influenza effect that was associated with stable body weight and reduced mortality. The anti-viral effect of Cordyceps extract on influenza infection was mediated presumably by increased IL-12 expression and greater number of NK cells. However, high TNF-α expression after infection of H1N1 virus in mice not receiving treatment with Cordyceps extract suggested a two-sided effect of the extract on host immune regulation.

  10. Peramivir analogues bearing hydrophilic side chains exhibit higher activities against H275Y mutant than wild-type influenza virus.

    Science.gov (United States)

    Chiu, Din-Chi; Lin, Tzu-Chen; Huang, Wen-I; Cheng, Ting-Jen; Tsai, Keng-Chang; Fang, Jim-Min

    2017-11-29

    Peramivir is an effective anti-influenza drug in the clinical treatment of influenza, but its efficacy toward the H275Y mutant is reduced. The previously reported cocrystal structures of inhibitors in the mutant neuraminidase (NA) suggest that the hydrophobic side chain should be at the origin of reduced binding affinity. In contrast, zanamivir having a hydrophilic glycerol side chain still possesses high affinity toward the H275Y NA. We thus designed five peramivir analogues (5-9) carrying hydrophilic glycol or glycerol side chains, and evaluated their roles in anti-influenza activity, especially for the H275Y mutant. The synthetic sequence involves a key step of (3 + 2) cycloaddition reactions between alkenes and nitrile oxides to construct the scaffold of peramivir carrying the desired hydrophilic side chains and other appropriate functional groups. The molecular docking experiments reveal that the hydrophilic side chain can provide extra hydrogen bonding with the translocated Glu-276 residue in the H275Y NA active site. Thus, the H275Y mutant may be even more sensitive than wild-type virus toward the peramivir analogues bearing hydrophilic side chains. Notably, the peramivir analogue bearing a glycerol side chain inhibits the H275Y mutant with an IC 50 value of 35 nM, which is better than the WSN virus by 9 fold.

  11. Computational screen and experimental validation of anti-influenza effects of quercetin and chlorogenic acid from traditional Chinese medicine

    Science.gov (United States)

    Liu, Zekun; Zhao, Junpeng; Li, Weichen; Shen, Li; Huang, Shengbo; Tang, Jingjing; Duan, Jie; Fang, Fang; Huang, Yuelong; Chang, Haiyan; Chen, Ze; Zhang, Ran

    2016-01-01

    The Influenza A virus is a great threat for human health, while various subtypes of the virus made it difficult to develop drugs. With the development of state-of-art computational chemistry, computational molecular docking could serve as a virtual screen of potential leading compound. In this study, we performed molecular docking for influenza A H1N1 (A/PR/8/34) with small molecules such as quercetin and chlorogenic acid, which were derived from traditional Chinese medicine. The results showed that these small molecules have strong binding abilities with neuraminidase from H1N1 (A/PR/8/34). Further details showed that the structural features of the molecules might be helpful for further drug design and development. The experiments in vitro, in vivo have validated the anti-influenza effect of quercetin and chlorogenic acid, which indicating comparable protection effects as zanamivir. Taken together, it was proposed that chlorogenic acid and quercetin could be employed as the effective lead compounds for anti-influenza A H1N1.

  12. A qualitative analysis of the beliefs of Japanese anti-influenza vaccination website authors

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Okuhara

    2018-04-01

    Full Text Available Background: Influenza vaccine coverage among the Japanese population is less than optimal. Anti-vaccination sentiment exists worldwide, and Japan is no exception. Anti-influenza vaccination activists argue on the internet that influenza vaccine has little or no efficacy and a high risk of side effects, and they warn that people should forgo vaccination. We conducted a qualitative analysis to explore beliefs underlying the messages of anti-influenza vaccination websites, by focusing on the perceived value these beliefs provide to those who hold them. Methods: We conducted online searches in January 2017 using two major Japanese search engines (Google Japan and Yahoo! Japan. Targeted websites were classified as “pro”, “anti”, or “neutral” depending on their claims. We applied a dual analytic approach—inductive thematic analysis and deductive interpretative analysis—to textual data of the anti websites. Results: Of the 113 anti websites, we identified two themes that correspond to beliefs: it is necessary to 1 protect others against risks and exploitation related to influenza vaccination, and 2 educate others about hidden truths and self-determination. Authors of anti websites ascribed two values (people's “safety” and one's own “self-esteem” to their beliefs. Discussion: Website authors may engage in anti-vaccination activities because they want to feel they are virtuous, saving people from harm caused by vaccination, and to boost their self-esteem, thinking “I am enlightening uninformed people.” The anti-vaccination beliefs of website authors were considered to be strong. In promoting vaccination, it would be better not to target outright vaccine refusers, such as the authors of anti-vaccination websites; it is preferable to target vaccine-hesitant people who are more amenable to changing their attitudes toward vaccination. We discuss possible means of promoting vaccination in that target population. Keywords

  13. Design, synthesis and biological evaluation of novel L-ascorbic acid-conjugated pentacyclic triterpene derivatives as potential influenza virus entry inhibitors.

    Science.gov (United States)

    Wang, Han; Xu, Renyang; Shi, Yongying; Si, Longlong; Jiao, Pingxuan; Fan, Zibo; Han, Xu; Wu, Xingyu; Zhou, Xiaoshu; Yu, Fei; Zhang, Yongmin; Zhang, Liangren; Zhang, Lihe; Zhou, Demin; Xiao, Sulong

    2016-03-03

    Since the influenza viruses can rapidly evolve, it is urgently required to develop novel anti-influenza agents possessing a novel mechanism of action. In our previous study, two pentacyclic triterpene derivatives (Q8 and Y3) have been found to have anti-influenza virus entry activities. Keeping the potential synergy of biological activity of pentacyclic triterpenes and l-ascorbic acid in mind, we synthesized a series of novel l-ascorbic acid-conjugated pentacyclic triterpene derivatives (18-26, 29-31, 35-40 and 42-43). Moreover, we evaluated these novel compounds for their anti-influenza activities against A/WSN/33 virus in MDCK cells. Among all evaluated compounds, the 2,3-O,O-dibenzyl-6-deoxy-l-ascorbic acid-betulinic acid conjugate (30) showed the most significant anti-influenza activity with an EC50 of 8.7 μM, and no cytotoxic effects on MDCK cells were observed. Time-of-addition assay indicated that compound 30 acted at an early stage of the influenza life cycle. Further analyses revealed that influenza virus-induced hemagglutination of chicken red blood cells was inhibited by treatment of compound 30, and the interaction between the influenza hemagglutinin (HA) and compound 30 was determined by surface plasmon resonance (SPR) with a dissociation constant of KD = 3.76 μM. Finally, silico docking studies indicated that compound 30 and its derivative 31 were able to occupy the binding pocket of HA for sialic acid receptor. Collectively, these results suggested that l-ascorbic acid-conjugated pentacyclic triterpenes were promising anti-influenza entry inhibitors, and HA protein associated with viral entry was a promising drug target. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. A dual character of flavonoids in influenza A virus replication and spread through modulating cell-autonomous immunity by MAPK signaling pathways

    Science.gov (United States)

    Dong, Wenjuan; Wei, Xiuli; Zhang, Fayun; Hao, Junfeng; Huang, Feng; Zhang, Chunling; Liang, Wei

    2014-01-01

    Flavonoids are well known as a large class of polyphenolic compounds, which have a variety of physiological activities, including anti-influenza virus activity. The influenza A/WSN/33 infected A549 cells have been used to screen anti-influenza virus drugs from natural flavonoid compounds library. Unexpectedly, some flavonoid compounds significantly inhibited virus replication, while the others dramatically promoted virus replication. In this study, we attempted to understand these differences between flavonoid compounds in their antivirus mechanisms. Hesperidin and kaempferol were chosen as representatives of both sides, each of which exhibited the opposite effects on influenza virus replication. Our investigation revealed that the opposite effects produced by hesperidin and kaempferol on influenza virus were due to inducing the opposite cell-autonomous immune responses by selectively modulating MAP kinase pathways: hesperidin up-regulated P38 and JNK expression and activation, thus resulting in the enhanced cell-autonomous immunity; while kaempferol dramatically down-regulated p38 and JNK expression and activation, thereby suppressing cell-autonomous immunity. In addition, hesperidin restricted RNPs export from nucleus by down-regulating ERK activation, but kaempferol promoted RNPs export by up-regulating ERK activation. Our findings demonstrate that a new generation of anti-influenza virus drugs could be developed based on selective modulation of MAP kinase pathways to stimulate cell-autonomous immunity. PMID:25429875

  15. Salivary agglutinin and lung scavenger receptor cysteine-rich glycoprotein 340 have broad anti-influenza activities and interactions with surfactant protein D that vary according to donor source and sialylation

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L.; Ligtenberg, Antoon; White, Mitchell R.

    2006-01-01

    from this donor as compared with salivary gp-340 from another donor or several preparations of lung gp-340. Hence, the specificity of sialic acid linkages on gp-340 is an important determinant of anti-IAV activity. Gp-340 binds to SP-D (surfactant protein D), and we previously showed that lung gp-340...... has co-operative interactions with SP-D in viral neutralization and aggregation assays. We now report that salivary gp-340 can, in some cases, strongly antagonize certain antiviral activities of SP-D. This effect was associated with greater binding of salivary gp-340 to the carbohydrate recognition...

  16. Inhibitory Effect and Possible Mechanism of Action of Patchouli Alcohol against Influenza A (H2N2 Virus

    Directory of Open Access Journals (Sweden)

    Xue Wang

    2011-08-01

    Full Text Available In the present study, the anti-influenza A (H2N2 virus activity of patchouli alcohol was studied in vitro, in vivo and in silico. The CC50 of patchouli alcohol was above 20 µM. Patchouli alcohol could inhibit influenza virus with an IC50 of 4.03 ± 0.23 µM. MTT assay showed that the inhibition by patchouli alcohol appears strongly after penetration of the virus into the cell. In the influenza mouse model, patchouli alcohol showed obvious protection against the viral infection at a dose of 5 mg/kg/day. Flexible docking and molecular dynamic simulations indicated that patchouli alcohol was bound to the neuraminidase protein of influenza virus, with an interaction energy of –40.38 kcal mol–1. The invariant key active-site residues Asp151, Arg152, Glu119, Glu276 and Tyr406 played important roles during the binding process. Based on spatial and energetic criteria, patchouli alcohol interfered with the NA functions. Results presented here suggest that patchouli alcohol possesses anti-influenza A (H2N2 virus properties, and therefore is a potential source of anti-influenza agents for the pharmaceutical industry.

  17. Salivary agglutinin and lung scavenger receptor cysteine-rich glycoprotein 340 have broad anti-influenza activities and interactions with surfactant protein D that vary according to donor source and sialylation

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L.; Ligtenberg, Antoon; White, Mitchell R.

    2006-01-01

    from this donor as compared with salivary gp-340 from another donor or several preparations of lung gp-340. Hence, the specificity of sialic acid linkages on gp-340 is an important determinant of anti-IAV activity. Gp-340 binds to SP-D (surfactant protein D), and we previously showed that lung gp-340...... has co-operative interactions with SP-D in viral neutralization and aggregation assays. We now report that salivary gp-340 can, in some cases, strongly antagonize certain antiviral activities of SP-D. This effect was associated with greater binding of salivary gp-340 to the carbohydrate recognition...... domain of SP-D as compared with the binding of lung gp-340. These findings may relate to inter-individual variations in innate defence against highly pathogenic IAV and to effects of aspiration of oral contents on SP-D-mediated lung functions....

  18. Chinese herbal medicine compound Yi-Zhi-Hao pellet inhibits replication of influenza virus infection through activation of heme oxygenase-1

    Directory of Open Access Journals (Sweden)

    Jinqiu Yin

    2017-11-01

    Full Text Available As a leading cause of respiratory disease, influenza A virus (IAV presents a pandemic threat in annual seasonal outbreaks. Given the limitation of existing anti-influenza therapies, there remains to be a requirement for new drugs. Compound Yi-Zhi-Hao pellet (CYZH is a famous traditional Chinese medicine (TCM used in the clinic, whose formula has been recorded in Complication of National Standard for Traditional Chinese Medicine to treat common cold. In this study, we found that CYZH exhibited a broad-spectrum anti-influenza activity and inhibited the expression of viral RNA and proteins in vitro. Mechanistically, CYZH had no inhibitory activities against viral protein hemagglutinin and IAV RNA-dependent RNA polymerase. Instead, it induced activation of erythroid 2-related factor 2 (Nrf2 and nuclear factor kappa B (NF-κB, which subsequently upregulated heme oxygenase-1 (HO-1 expression. Also, CYZH protected cells from oxidative damage induced by reactive oxygen series. In conclusions, CYZH inhibits IAV replication in vitro, at least partly by activating expression of the Nrf2/HO-1 pathway.

  19. The susceptibility of circulating human influenza viruses to tizoxanide, the active metabolite of nitazoxanide.

    Science.gov (United States)

    Tilmanis, Danielle; van Baalen, Carel; Oh, Ding Yuan; Rossignol, Jean-Francois; Hurt, Aeron C

    2017-11-01

    Nitazoxanide is a thiazolide compound that was originally developed as an anti-parasitic agent, but has recently been repurposed for the treatment of influenza virus infections. Thought to exert its anti-influenza activity via the inhibition of hemagglutinin maturation and intracellular trafficking in infected cells, the effectiveness of nitazoxanide in treating patients with non-complicated influenza is currently being assessed in phase III clinical trials. Here, we describe the susceptibility of 210 seasonal influenza viruses to tizoxanide, the active circulating metabolite of nitazoxanide. An optimised cell culture-based focus reduction assay was used to determine the susceptibility of A(H1N1)pdm09, A(H3N2), and influenza B viruses circulating in the southern hemisphere from the period March 2014 to August 2016. Tizoxanide showed potent in vitro antiviral activity against all influenza viruses tested, including neuraminidase inhibitor-resistant viruses, allowing the establishment of a baseline level of susceptibility for each subtype. Median EC 50 values (±IQR) of 0.48 μM (0.33-0.71), 0.62 μM (0.56-0.75), 0.66 μM (0.62-0.69), and 0.60 μM (0.51-0.67) were obtained for A(H1N1)pdm09, A(H3N2), B(Victoria lineage), and B(Yamagata lineage) influenza viruses respectively. There was no significant difference in the median baseline tizoxanide susceptibility for each influenza subtype tested. This is the first report on the susceptibility of circulating viruses to tizoxanide. The focus reduction assay format described is sensitive, robust, and less laborious than traditional cell based antiviral assays, making it highly suitable for the surveillance of tizoxanide susceptibility in circulating seasonal influenza viruses. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Antiviral Activities of Several Oral Traditional Chinese Medicines against Influenza Viruses.

    Science.gov (United States)

    Ma, Lin-Lin; Ge, Miao; Wang, Hui-Qiang; Yin, Jin-Qiu; Jiang, Jian-Dong; Li, Yu-Huan

    2015-01-01

    Influenza is still a serious threat to human health with significant morbidity and mortality. The emergence of drug-resistant influenza viruses poses a great challenge to existing antiviral drugs. Traditional Chinese medicines (TCMs) may be an alternative to overcome the challenge. Here, 10 oral proprietary Chinese medicines were selected to evaluate their anti-influenza activities. These drugs exhibit potent inhibitory effects against influenza A H1N1, influenza A H3N2, and influenza B virus. Importantly, they demonstrate potent antiviral activities against drug-resistant strains. In the study of mechanisms, we found that Xiaoqinglong mixture could increase antiviral interferon production by activating p38 MAPK, JNK/SAPK pathway, and relative nuclear transcription factors. Lastly, our studies also indicate that some of these medicines show inhibitory activities against EV71 and CVB strains. In conclusion, the 10 traditional Chinese medicines, as kind of compound combination medicines, show broad-spectrum antiviral activities, possibly also including inhibitory activities against strains resistant to available antiviral drugs.

  1. A novel anti-influenza copper oxide containing respiratory face mask.

    Directory of Open Access Journals (Sweden)

    Gadi Borkow

    Full Text Available BACKGROUND: Protective respiratory face masks protect the nose and mouth of the wearer from vapor drops carrying viruses or other infectious pathogens. However, incorrect use and disposal may actually increase the risk of pathogen transmission, rather than reduce it, especially when masks are used by non-professionals such as the lay public. Copper oxide displays potent antiviral properties. A platform technology has been developed that permanently introduces copper oxide into polymeric materials, conferring them with potent biocidal properties. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that impregnation of copper oxide into respiratory protective face masks endows them with potent biocidal properties in addition to their inherent filtration properties. Both control and copper oxide impregnated masks filtered above 99.85% of aerosolized viruses when challenged with 5.66+/-0.51 and 6.17+/-0.37 log(10TCID(50 of human influenza A virus (H1N1 and avian influenza virus (H9N2, respectively, under simulated breathing conditions (28.3 L/min. Importantly, no infectious human influenza A viral titers were recovered from the copper oxide containing masks within 30 minutes (< or = 0.88 log(10TCID(50, while 4.67+/-1.35 log(10TCID(50 were recovered from the control masks. Similarly, the infectious avian influenza titers recovered from the copper oxide containing masks were < or = 0.97+/-0.01 log(10TCID(50 and from the control masks 5.03+/-0.54 log(10TCID(50. The copper oxide containing masks successfully passed Bacterial Filtration Efficacy, Differential Pressure, Latex Particle Challenge, and Resistance to Penetration by Synthetic Blood tests designed to test the filtration properties of face masks in accordance with the European EN 14683:2005 and NIOSH N95 standards. CONCLUSIONS/SIGNIFICANCE: Impregnation of copper oxide into respiratory protective face masks endows them with potent anti-influenza biocidal properties without altering their physical

  2. Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Yutaka; Kakisaka, Michinori; Chutiwitoonchai, Nopporn [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tajima, Shigeru [Department of Virology I, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo 162-8640 (Japan); Hikono, Hirokazu; Saito, Takehiko [Influenza and Prion Disease Research Center, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan); Aida, Yoko, E-mail: aida@riken.jp [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2014-07-18

    Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified a novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC{sub 50} values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets.

  3. Synthesis and biological evaluation of 12N-substituted tricyclic matrinic derivatives as a novel family of anti-influenza agents.

    Science.gov (United States)

    Tang, Sheng; Li, Yu-Huan; Cheng, Xin-Yue; Yin, Jin-Qiu; Li, Ying-Hong; Song, Dan-Qing; Wang, Yan-Xiang; Liu, Zhan-Dong

    2018-02-21

    Influenza is still a serious threat to human health with significant morbidity and mortality, so it is desirable to develop novel anti-flu drug agents with novel structures. The main purpose of this research was to explore broad-spectrum anti-flu agents and provide antiviral stockpiles in response to potential future influenza pandemics. Fifteen novel 12N-substituted tricyclic matrinic derivatives were synthesized and evaluated for their anti-influenza activities against H1N1 subtype taking 12N-p-cyanobenzenesulfonyl matrinane (1) as the lead. All prepared compounds were characterized by 1H NMR, 13C NMR and ESI-HRMS. The pharmacokinetics (PK) profile of the key compound was also examined in this study. The structure-activity relationship study indicated that a suitable benzyl groups on 12N atom might be beneficial for the activity. Among them, 12N-p-carboxybenzyl matrinic butane (17g) exhibited the most promising activity with an IC50 value of 16.2 μM and a selective index (SI) value of over 33.4. In addition, compound 17g displayed a good in vivo pharmacokinetic profile with area under the curve (AUC0-∞) value of 9.89 μM•h. We consider tricyclic matrinic butane derivatives to be a new class of anti-influenza agents and this study provided useful information on further optimization. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. Inability of NS1 protein from an H5N1 influenza virus to activate PI3K/Akt signaling pathway correlates to the enhanced virus replication upon PI3K inhibition

    Directory of Open Access Journals (Sweden)

    Li Weizhong

    2012-04-01

    Full Text Available Abstract Background Phosphatidylinositol 3-kinase (PI3K/Akt signaling pathway, activated during influenza A virus infection, can promote viral replication via multiple mechanisms. Direct binding of NS1 protein to p85β subunit of PI3K is required for activation of PI3K/Akt signaling. Binding and subsequent activation of PI3K is believed to be a conserved character of influenza A virus NS1 protein. Sequence variation of NS1 proteins in different influenza A viruses led us to investigate possible deviation from the conservativeness. Results In the present study, NS1 proteins from four different influenza A virus subtypes/strains were tested for their ability to bind p85β subunit of PI3K and to activate PI3K/Akt. All NS1 proteins efficiently bound to p85β and activated PI3K/Akt, with the exception of NS1 protein from an H5N1 virus (A/Chicken/Guangdong/1/05, abbreviated as GD05, which bound to p85β but failed to activate PI3K/Akt, implying that as-yet-unidentified domain(s in NS1 may alternatively mediate the activation of PI3K. Moreover, PI3K inhibitor, LY294002, did not suppress but significantly increased the replication of GD05 virus. Conclusions Our study indicates that activation of PI3K/Akt by NS1 protein is not highly conserved among influenza A viruses and inhibition of the PI3K/Akt pathway as an anti-influenza strategy may not work for all influenza A viruses.

  5. Structure-activity relationships of 3-O-β-chacotriosyl oleanic acid derivatives as entry inhibitors for highly pathogenic H5N1 influenza virus.

    Science.gov (United States)

    Li, Sumei; Jia, Xiuhua; Shen, Xintian; Wei, Zhuwen; Jiang, Zhiyan; Liao, Yixian; Guo, Yiming; Zheng, Xiaojun; Zhong, Guohua; Song, Gaopeng

    2017-08-15

    Highly pathogenic H5N1 virus (H5N1) entry is a key target for the development of novel anti-influenza agents with new mechanisms of action. In our continuing efforts to identify novel potential anti-H5N1 entry inhibitors, a series of 3-O-β-chacotriosyl oleanolic acid analogs have been designed, synthesized and evaluated as H5N1 entry inhibitors based on two small molecule inhibitors 1 and 2 previously discovered by us. The anti-H5N1 entry activities were determined based on HA/HIV and VSVG/HIV entry assays. Compound 15 displayed the most promising anti-H5N1 entry activities with average IC 50 values of 4.05μM and good selective index (22.9). Detailed structure-activity relationships (SARs) studies suggested that either the introduction of an additional oxo group to position 11 at OA or alteration of the C-3 configuration of OA from 3β- to 3α-forms can significantly enhance the selective index while maintaining their antiviral activities in vitro. Molecular simulation analysis confirmed that the compounds exert their inhibitory activity through binding tightly to hemagglutinin (HA2) protein near the fusion peptide and prevent virus entry. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Modes of Antiviral Action of Chemical Portions and Constituents from Woad Root Extract against Influenza Virus A FM1

    Directory of Open Access Journals (Sweden)

    Jia-Hang Su

    2016-01-01

    Full Text Available Woad root has been used for the prevention of influenza for hundreds of years in many Asian countries. In this study, the antiviral modes of clemastanin B (CB, epigoitrin, phenylpropanoid portion (PEP, and the mixture of phenylpropanoids, alkaloids, and organic acid portions (PEP + ALK + OA from wood root extract against influenza virus A FM1 were investigated. The results revealed that CB, epigoitrin, PEP, and PEP + ALK + OA exert their anti-influenza activity via inhibiting the virus multiplication, prophylaxis, and blocking the virus attachment. The primary mode of action of PEP and PEP + ALK + OA is the inhibition of virus replication. The inhibitory effect on virus attachment and multiplication is the main modes for epigoitrin. All the compounds or chemical portions from woad root extract tested in this study do not have direct virucidal activity. Our results provided the comprehensive analysis of the antiviral mechanism of wood root extract.

  7. Reverse Genetics of Influenza B Viruses.

    Science.gov (United States)

    Nogales, Aitor; Perez, Daniel R; Santos, Jefferson; Finch, Courtney; Martínez-Sobrido, Luis

    2017-01-01

    Annual influenza epidemics are caused not only by influenza A viruses but also by influenza B viruses. Initially established for the generation of recombinant influenza A viruses, plasmid-based reverse genetics techniques have allowed researchers the generation of wild type and mutant viruses from full-length cDNA copies of the influenza viral genome. These reverse genetics approaches have allowed researchers to answer important questions on the biology of influenza viruses by genetically engineering infectious recombinant viruses. This has resulted in a better understanding of the molecular biology of influenza viruses, including both viral and host factors required for genome replication and transcription. With the ability to generate recombinant viruses containing specific mutations in the viral genome, these reverse genetics tools have also allowed the identification of viral and host factors involved in influenza pathogenesis, transmissibility, host-range interactions and restrictions, and virulence. Likewise, reverse genetics techniques have been used for the implementation of inactivated or live-attenuated influenza vaccines and the identification of anti-influenza drugs and their mechanism of antiviral activity. In 2002, these reverse genetics approaches allowed also the recovery of recombinant influenza B viruses entirely from plasmid DNA. In this chapter we describe the cloning of influenza B/Brisbane/60/2008 viral RNAs into the ambisense pDP-2002 plasmid and the experimental procedures for the successful generation of recombinant influenza B viruses.

  8. In Vitro inhibitory activity of Alpinia katsumadai extracts against influenza virus infection and hemagglutination

    Directory of Open Access Journals (Sweden)

    Park Su-Jin

    2010-11-01

    Full Text Available Abstract Background Alpinia katsumadai (AK extracts and fractions were tested for in vitro antiviral activities against influenza virus type A, specially human A/PR/8/34 (H1N1 and avian A/Chicken/Korea/MS96/96 (H9N2, by means of time-of-addition experiments; pre-treatment, simultaneous treatment, and post treatment. Results In pre-treatment assay, the AK extracts and AK fractions did not show significant antiviral activity. During the simultaneous treatment assay, one AK extract and five AK fractions designated as AK-1 to AK-3, AK-5, AK-10, and AK-11 showed complete inhibition of virus infectivity against A/PR/8/34 (H1N1 and A/Chicken/Korea/MS96/96 (H9N2. The 50% effective inhibitory concentrations (EC50 of these one AK extracts and five AK fractions with exception of the AK-9 were from 0.8 ± 1.4 to 16.4 ± 4.5 μg/mL against A/PR/8/34 (H1N1. The two AK extracts and three AK fractions had EC50 values ranging from μg/mL against A/Chicken/Korea/MS96/96 (H9N2. By the hemagglutination inhibition (HI assay, the two AK extracts and five AK fractions completely inhibited viral adsorption onto chicken RBCs at less than 100 μg/mL against both A/PR/8/34 (H1N1 and A/Chicken/Korea/MS96/96 (H9N2. Interestingly, only AK-3 was found with inhibition for both viral attachment and viral replication after showing extended antiviral activity during the post treatment assay and quantitative real-time PCR. Conclusions These results suggest that AK extracts and fractions had strong anti-influenza virus activity that can inhibit viral attachment and/or viral replication, and may be used as viral prophylaxis.

  9. Wide prevalence of heterosubtypic broadly neutralizing human anti-influenza A antibodies.

    Science.gov (United States)

    Sui, Jianhua; Sheehan, Jared; Hwang, William C; Bankston, Laurie A; Burchett, Sandra K; Huang, Chiung-Yu; Liddington, Robert C; Beigel, John H; Marasco, Wayne A

    2011-04-15

    Lack of life-long immunity against influenza viruses represents a major global health care problem with profound medical and economic consequences. A greater understanding of the broad-spectrum "heterosubtypic" neutralizing human antibody (BnAb) response to influenza should bring us closer toward a universal influenza vaccine. Serum samples obtained from 77 volunteers in an H5N1 vaccine study were analyzed for cross-reactive antibodies (Abs) against both subtype hemagglutinins (HAs) and a highly conserved pocket on the HA stem of Group 1 viruses. Cross-reactive Abs in commercial intravenous immunoglobulin were affinity purified using H5-coupled beads followed by step-wise monoclonal antibody competition or acid elution. Enzyme-linked immunosorbent assays were used to quantify cross-binding, and neutralization activity was determined with HA-pseudotyped viruses. Prevaccination serum samples have detectable levels of heterosubtypic HA binding activity to both Group 1 and 2 influenza A viruses, including subtypes H5 and H7, respectively, to which study subjects had not been vaccinated. Two different populations of Broadly neutralizing Abs (BnAbs) were purified from intravenous immunoglobulin by H5 beads: ~0.01% of total immunoglobulin G can bind to HAs from both Group 1 and 2 and neutralize H1N1 and H5N1 viruses; ~0.001% is F10-like Abs directed against the HA stem pocket on Group 1 viruses. These data--to our knowledge, for the first time--quantitatively show the presence, albeit at low levels, of two populations of heterosubtypic BnAbs against influenza A in human serum. These observations warrant further investigation to determine their origin, host polymorphism(s) that may affect their expression levels and how to boost these BnAb responses by vaccination to reach sustainable protective levels.

  10. Antiviral Activity of Some Plants Used in Nepalese Traditional Medicine

    Directory of Open Access Journals (Sweden)

    M. Rajbhandari

    2009-01-01

    Full Text Available Methanolic extracts of 41 plant species belonging to 27 families used in the traditional medicine in Nepal have been investigated for in vitro antiviral activity against Herpes simplex virus type 1 (HSV-1 and influenza virus A by dye uptake assay in the systems HSV-1/Vero cells and influenza virus A/MDCK cells. The extracts of Astilbe rivularis, Bergenia ciliata, Cassiope fastigiata and Thymus linearis showed potent anti-herpes viral activity. The extracts of Allium oreoprasum, Androsace strigilosa, Asparagus filicinus, Astilbe rivularis, Bergenia ciliata and Verbascum thapsus exhibited strong anti-influenza viral activity. Only the extracts of A. rivularis and B. ciliata demonstrated remarkable activity against both viruses.

  11. Xanthones from Polygala karensium inhibit neuraminidases from influenza A viruses

    DEFF Research Database (Denmark)

    Dao, Trong Tuan; Dang, Thai Trung; Nguyen, Phi Hung

    2012-01-01

    The emergence of the H1N1 swine flu pandemic has the possibility to develop the occurrence of disaster- or drug-resistant viruses by additional reassortments in novel influenza A virus. In the course of an anti-influenza screening program for natural products, 10 xanthone derivatives (1-10) were...

  12. The C-Terminal Tail of TRIM56 Dictates Antiviral Restriction of Influenza A and B Viruses by Impeding Viral RNA Synthesis.

    Science.gov (United States)

    Liu, Baoming; Li, Nan L; Shen, Yang; Bao, Xiaoyong; Fabrizio, Thomas; Elbahesh, Husni; Webby, Richard J; Li, Kui

    2016-05-01

    Accumulating data suggest that tripartite-motif-containing (TRIM) proteins participate in host responses to viral infections, either by acting as direct antiviral restriction factors or through regulating innate immune signaling of the host. Of >70 TRIMs, TRIM56 is a restriction factor of several positive-strand RNA viruses, including three members of the family Flaviviridae(yellow fever virus, dengue virus, and bovine viral diarrhea virus) and a human coronavirus (OC43), and this ability invariably depends upon the E3 ligase activity of TRIM56. However, the impact of TRIM56 on negative-strand RNA viruses remains unclear. Here, we show that TRIM56 puts a check on replication of influenza A and B viruses in cell culture but does not inhibit Sendai virus or human metapneumovirus, two paramyxoviruses. Interestingly, the anti-influenza virus activity was independent of the E3 ligase activity, B-box, or coiled-coil domain. Rather, deletion of a 63-residue-long C-terminal-tail portion of TRIM56 abrogated the antiviral function. Moreover, expression of this short C-terminal segment curtailed the replication of influenza viruses as effectively as that of full-length TRIM56. Mechanistically, TRIM56 was found to specifically impede intracellular influenza virus RNA synthesis. Together, these data reveal a novel antiviral activity of TRIM56 against influenza A and B viruses and provide insights into the mechanism by which TRIM56 restricts these medically important orthomyxoviruses. Options to treat influenza are limited, and drug-resistant influenza virus strains can emerge through minor genetic changes. Understanding novel virus-host interactions that alter influenza virus fitness may reveal new targets/approaches for therapeutic interventions. We show here that TRIM56, a tripartite-motif protein, is an intrinsic host restriction factor of influenza A and B viruses. Unlike its antiviral actions against positive-strand RNA viruses, the anti-influenza virus activity of TRIM56

  13. Autophagic machinery activated by dengue virus enhances virus replication

    International Nuclear Information System (INIS)

    Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

    2008-01-01

    Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication

  14. Influenza virus neutralizing antibodies and IgG isotype profiles after immunization of mice with influenza A subunit vaccine using various adjuvants

    NARCIS (Netherlands)

    Benne, CA; Harmsen, M; vanderGraaff, W; Verheul, AFM; Snippe, H; Kraaijeveld, CA

    The influence of various adjuvants on the development of influenza virus neutralizing antibodies and distribution of anti-influenza virus IgG isotypes after immunization of mice with influenza A (H3N2) subunit vaccine was investigated. Serum titres of influenza virus neutralizing antibodies and

  15. Patients with humoral primary immunodeficiency do not develop protective anti-influenza antibody titers after vaccination with trivalent subunit influenza vaccine

    NARCIS (Netherlands)

    van Assen, Sander; Holvast, Albert; Telgt, Denise S.C.; Benne, Cornelis A.; de Haan, Aalzen; Westra, Johanna; Kallenberg, Cornelis; Bijl, Marc

    Yearly influenza vaccination is recommended for patients with humoral primary immunodeficiency (hPID). However, humoral responses following vaccination can be expected to be reduced in these patients.The efficacy of influenza vaccination in patients with hPID, anti-influenza antibody responses was

  16. Activity of andrographolide against dengue virus.

    Science.gov (United States)

    Panraksa, Patcharee; Ramphan, Suwipa; Khongwichit, Sarawut; Smith, Duncan R

    2017-03-01

    Dengue is the most prevalent arthropod-transmitted viral illness of humans, with an estimated 100 million symptomatic infections occurring each year and more than 2.5 billion people living at risk of infection. There are no approved antiviral agents against dengue virus, and there is only limited introduction of a dengue vaccine in some countries. Andrographolide is derived from Andrographis paniculata, a medicinal plant traditionally used to treat a number of conditions including infections. The antiviral activity of andrographolide against dengue virus (DENV) serotype 2 was evaluated in two cell lines (HepG2 and HeLa) while the activity against DENV 4 was evaluated in one cell line (HepG2). Results showed that andrographolide had significant anti-DENV activity in both cell lines, reducing both the levels of cellular infection and virus output, with 50% effective concentrations (EC 50 ) for DENV 2 of 21.304 μM and 22.739 μM for HepG2 and HeLa respectively. Time of addition studies showed that the activity of andrographolide was confined to a post-infection stage. These results suggest that andrographolide has the potential for further development as an anti-viral agent for dengue virus infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Molecular structures of viruses from Raman optical activity

    DEFF Research Database (Denmark)

    Blanch, Ewan W.; Hecht, Lutz; Syme, Christopher D.

    2002-01-01

    A vibrational Raman optical activity (ROA) study of a range of different structural types of virus exemplified by filamentous bacteriophage fd, tobacco mosaic virus, satellite tobacco mosaic virus, bacteriophage MS2 and cowpea mosaic virus has revealed that, on account of its sensitivity to chira...

  18. Activation of human immunodeficiency virus by radiation

    International Nuclear Information System (INIS)

    Beer, J.Z.; Zmudzka, B.Z.

    1991-01-01

    It was recently demonstrated that ultraviolet radiation (UVR) can induce the HIV promoter as well as activate the complete virus in cultured cells (Valerie et al., 1988). This and subsequent observations, reviewed in this article, suggest a possibility that radiation exposure may accelerate development of AIDS in HIV-infected individuals. They also indicate that studies on HIV activation by stressors, including radiation, may advance our understanding of some phenomena that follow HIV infection. (author)

  19. Construction of Eukaryotic Expression Vector with mBD1-mBD3 Fusion Genes and Exploring Its Activity against Influenza A Virus

    Directory of Open Access Journals (Sweden)

    Wanyi Li

    2014-03-01

    Full Text Available Influenza (flu pandemics have exhibited a great threat to human health throughout history. With the emergence of drug-resistant strains of influenza A virus (IAV, it is necessary to look for new agents for treatment and transmission prevention of the flu. Defensins are small (2–6 kDa cationic peptides known for their broad-spectrum antimicrobial activity. Beta-defensins (β-defensins are mainly produced by barrier epithelial cells and play an important role in attacking microbe invasion by epithelium. In this study, we focused on the anti-influenza A virus activity of mouse β-defensin 1 (mBD1 and β defensin-3 (mBD3 by synthesizing their fusion peptide with standard recombinant methods. The eukaryotic expression vectors pcDNA3.1(+/mBD1-mBD3 were constructed successfully by overlap-PCR and transfected into Madin-Darby canine kidney (MDCK cells. The MDCK cells transfected by pcDNA3.1(+/mBD1-mBD3 were obtained by G418 screening, and the mBD1-mBD3 stable expression pattern was confirmed in MDCK cells by RT-PCR and immunofluorescence assay. The acquired stable transfected MDCK cells were infected with IAV (A/PR/8/34, H1N1, 0.1 MOI subsequently and the virus titers in cell culture supernatants were analyzed by TCID50 72 h later. The TCID50 titer of the experimental group was clearly lower than that of the control group (p < 0.001. Furthermore, BALB/C mice were injected with liposome-encapsulated pcDNA3.1(+/mBD1-mBD3 through muscle and then challenged with the A/PR/8/34 virus. Results showed the survival rate of 100% and lung index inhibitory rate of 32.6% in pcDNA3.1(+/mBD1-mBD3group; the TCID50 titer of lung homogenates was clearly lower than that of the control group (p < 0.001. This study demonstrates that mBD1-mBD3 expressed by the recombinant plasmid pcDNA3.1(+/mBD1-mBD3 could inhibit influenza A virus replication both in vitro and in vivo. These observations suggested that the recombinant mBD1-mBD3 might be developed into an agent for

  20. Invasive pneumococcal and meningococcal disease : association with influenza virus and respiratory syncytial virus activity?

    NARCIS (Netherlands)

    Jansen, A G S C; Sanders, E A M; VAN DER Ende, A; VAN Loon, A M; Hoes, A W; Hak, E

    2008-01-01

    Few studies have examined the relationship between viral activity and bacterial invasive disease, considering both influenza virus and respiratory syncytial virus (RSV). This study aimed to assess the potential relationship between invasive pneumococcal disease (IPD), meningococcal disease (MD), and

  1. Activity of andrographolide against chikungunya virus infection.

    Science.gov (United States)

    Wintachai, Phitchayapak; Kaur, Parveen; Lee, Regina Ching Hua; Ramphan, Suwipa; Kuadkitkan, Atichat; Wikan, Nitwara; Ubol, Sukathida; Roytrakul, Sittiruk; Chu, Justin Jang Hann; Smith, Duncan R

    2015-09-18

    Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This study sought to determine the potential of andrographolide as an inhibitor of CHIKV infection. Andrographolide showed good inhibition of CHIKV infection and reduced virus production by approximately 3log10 with a 50% effective concentration (EC50) of 77 μM without cytotoxicity. Time-of-addition and RNA transfection studies showed that andrographolide affected CHIKV replication and the activity of andrographolide was shown to be cell type independent. This study suggests that andrographolide has the potential to be developed further as an anti-CHIKV therapeutic agent.

  2. Activity of andrographolide against chikungunya virus infection

    OpenAIRE

    Phitchayapak Wintachai; Parveen Kaur; Regina Ching Hua Lee; Suwipa Ramphan; Atichat Kuadkitkan; Nitwara Wikan; Sukathida Ubol; Sittiruk Roytrakul; Justin Jang Hann Chu; Duncan R. Smith

    2015-01-01

    Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This stud...

  3. Investigation of the salicylaldehyde thiosemicarbazone scaffold for inhibition of influenza virus PA endonuclease.

    Science.gov (United States)

    Rogolino, Dominga; Bacchi, Alessia; De Luca, Laura; Rispoli, Gabriele; Sechi, Mario; Stevaert, Annelies; Naesens, Lieve; Carcelli, Mauro

    2015-10-01

    The influenza virus PA endonuclease is an attractive target for the development of novel anti-influenza virus therapeutics, which are urgently needed because of the emergence of drug-resistant viral strains. Reported PA inhibitors are assumed to chelate the divalent metal ion(s) (Mg²⁺ or Mn²⁺) in the enzyme's catalytic site, which is located in the N-terminal part of PA (PA-Nter). In the present work, a series of salicylaldehyde thiosemicarbazone derivatives have been synthesized and evaluated for their ability to inhibit the PA-Nter catalytic activity. Compounds 1-6 have been evaluated against influenza virus, both in enzymatic assays with influenza virus PA-Nter and in virus yield assays in MDCK cells. In order to establish a structure-activity relationship, the hydrazone analogue of the most active thiosemicarbazone has also been evaluated. Since chelation may represent a mode of action of such class of molecules, we studied the interaction of two of them, one with and one without biological activity versus the PA enzyme, towards Mg²⁺, the ion that is probably involved in the endonuclease activity of the heterotrimeric influenza polymerase complex. The crystal structure of the magnesium complex of the o-vanillin thiosemicarbazone ligand 1 is also described. Moreover, docking studies of PA endonuclease with compounds 1 and 2 were performed, to further analyse the possible mechanism of action of this class of inhibitors.

  4. Mielitis transversa relacionada con vacunación anti-influenza A(H1N1

    Directory of Open Access Journals (Sweden)

    María Florencia Arcondo

    2011-04-01

    Full Text Available La mielitis transversa es una enfermedad inflamatoria que se caracteriza por disfunción de la médula espinal. Las causas reconocidas de mielitis transversa son autoinmunes, enfermedades desmielinizantes, post infecciosas y post vacunales, aunque hasta el 50% de los casos son idiopáticas. Las vacunas contra la rubéola, paperas, rabia y gripe estacional han sido asociadas a diversos trastornos neurológicos, como el Síndrome de Guillain Barré, la encefalomielitis diseminada aguda (ADEM y la mielitis transversa. Como mecanismo preventivo luego de la pandemia de 2009, en febrero del año 2010 se inició en nuestro país la campaña de vacunación contra la Influenza A (H1N1. Se presenta el caso de una paciente con hipoestesias que aparecieron cuatro días después de haber recibido la vacuna monovalente anti-influenza A (H1N1 y progresaron con evidente nivel sensitivo. La paciente cumplía criterios diagnósticos de mielitis transversa, según el Transverse Myelitis Consortium Working Group. Tuvo remisión de las imágenes de la resonancia magnética y estabilidad clínica sin tratamiento con corticoides. Se discuten aspectos diagnósticos, pronósticos y terapéuticos de esta entidad clínica.

  5. Influenza virus activity in Papua New Guinea.

    Science.gov (United States)

    Sungu, M; Sanders, R

    1991-09-01

    Influenza viruses remain a major cause of respiratory disease in both developed and developing countries. A great deal of information concerning the structure, pathology and modes of transmission of these viruses has been accumulated, but no means of successfully combating them have, as yet, been devised. The most appropriate strategy for limiting the effects of influenza is to monitor the emergence and spread of new strains carefully and warn the public and at-risk groups of impending epidemics. In Papua New Guinea, as in most other developing countries, the major at-risk groups are the very young and the elderly. In the past, influenza epidemics were rare and affected the whole community, but with modern development and increased mobility the transmission dynamics of influenza have changed. The only influenza surveillance centre in Papua New Guinea is at the Papua New Guinea Institute of Medical Research in Goroka, and the surveillance activities of this centre are limited to the immediately surrounding areas. There is a need to establish a national influenza surveillance network, to provide nation-wide monitoring of influenza activity, and to provide a central repository of current information on influenza infections in the country.

  6. Efficient production of infectious viruses requires enzymatic activity of Epstein-Barr virus protein kinase.

    Science.gov (United States)

    Murata, Takayuki; Isomura, Hiroki; Yamashita, Yoriko; Toyama, Shigenori; Sato, Yoshitaka; Nakayama, Sanae; Kudoh, Ayumi; Iwahori, Satoko; Kanda, Teru; Tsurumi, Tatsuya

    2009-06-20

    The Epstein-Barr virus (EBV) BGLF4 gene product is the only protein kinase encoded by the virus genome. In order to elucidate its physiological roles in viral productive replication, we here established a BGLF4-knockout mutant and a revertant virus. While the levels of viral DNA replication of the deficient mutant were equivalent to those of the wild-type and the revertant, virus production was significantly impaired. Expression of the BGLF4 protein in trans fully complemented the low yield of the mutant virus, while expression of a kinase-dead (K102I) form of the protein failed to restore the virus titer. These results demonstrate that BGLF4 plays a significant role in production of infectious viruses and that the kinase activity is crucial.

  7. Antiviral activities of streptomycetes against tobacco mosaic virus ...

    African Journals Online (AJOL)

    Antiviral activities of streptomycetes against tobacco mosaic virus (TMV) in Datura plant: Evaluation of different organic compounds in their metabolites. ... of different compounds. Key words: Antiviral activity, tobacco mosaic virus, actinomycetes, Streptomyces, Datura metel, GC-MS analysis, human pathogenic bacteria.

  8. Arginine-rich histones have strong antiviral activity for influenza A viruses.

    Science.gov (United States)

    Hoeksema, Marloes; Tripathi, Shweta; White, Mitchell; Qi, Li; Taubenberger, Jeffery; van Eijk, Martin; Haagsman, Henk; Hartshorn, Kevan L

    2015-10-01

    While histones are best known for DNA binding and transcription-regulating properties, they also have antimicrobial activity against a broad range of potentially pathogenic organisms. Histones are abundant in neutrophil extracellular traps, where they play an important role in NET-mediated antimicrobial killing. Here, we show anti-influenza activity of histones against both seasonal H3N2 and H1N1, but not pandemic H1N1. The arginine rich histones, H3 and H4, had greater neutralizing and viral aggregating activity than the lysine rich histones, H2A and H2B. Of all core histones, histone H4 is most potent in neutralizing IAV, and incubation with IAV with histone H4 results in a decrease in uptake and viral replication by epithelial cells when measured by qRT-PCR. The antiviral activity of histone H4 is mediated principally by direct effects on viral particles. Histone H4 binds to IAV as assessed by ELISA and co-sedimentation of H4 with IAV. H4 also induces aggregation, as assessed by confocal microscopy and light transmission assays. Despite strong antiviral activity against the seasonal IAV strains, H4 was inactive against pandemic H1N1. These findings indicate a possible role for histones in the innate immune response against IAV. © The Author(s) 2015.

  9. Mielitis transversa relacionada con vacunación anti-influenza A(H1N1 Transverse myelitis associated with anti-influenza A (H1N1 vaccination

    Directory of Open Access Journals (Sweden)

    María Florencia Arcondo

    2011-04-01

    Full Text Available La mielitis transversa es una enfermedad inflamatoria que se caracteriza por disfunción de la médula espinal. Las causas reconocidas de mielitis transversa son autoinmunes, enfermedades desmielinizantes, post infecciosas y post vacunales, aunque hasta el 50% de los casos son idiopáticas. Las vacunas contra la rubéola, paperas, rabia y gripe estacional han sido asociadas a diversos trastornos neurológicos, como el Síndrome de Guillain Barré, la encefalomielitis diseminada aguda (ADEM y la mielitis transversa. Como mecanismo preventivo luego de la pandemia de 2009, en febrero del año 2010 se inició en nuestro país la campaña de vacunación contra la Influenza A (H1N1. Se presenta el caso de una paciente con hipoestesias que aparecieron cuatro días después de haber recibido la vacuna monovalente anti-influenza A (H1N1 y progresaron con evidente nivel sensitivo. La paciente cumplía criterios diagnósticos de mielitis transversa, según el Transverse Myelitis Consortium Working Group. Tuvo remisión de las imágenes de la resonancia magnética y estabilidad clínica sin tratamiento con corticoides. Se discuten aspectos diagnósticos, pronósticos y terapéuticos de esta entidad clínica.Transverse myelitis is an inflammatory disorder characterized by spinal cord dysfunction. Infectious, autoimmune, postinfectious and postvaccination diseases are the most common recognized causes of transverse myelitis, but near 50% of the cases are finally assumed as idiopathic. Rubeolla, mumps, rabies and influenza vaccines were associated with many neurologic complications, such as Guillain Barré Syndrome, acute disseminated encephalomyelitis (ADEM and transverse myelitis. As a prevention measure after the 2009 pandemia, in February 2010 a National Campaigne of Vaccination against the Influenza A (H1N1 was started in our country. We report a case of a woman who received a monovalent Influenza A (H1N1 vaccine and four days after, began with sensory

  10. Neuraminidase and hemagglutinin matching patterns of a highly pathogenic avian and two pandemic H1N1 influenza A viruses.

    Directory of Open Access Journals (Sweden)

    Yonghui Zhang

    Full Text Available BACKGROUND: Influenza A virus displays strong reassortment characteristics, which enable it to achieve adaptation in human infection. Surveying the reassortment and virulence of novel viruses is important in the prevention and control of an influenza pandemic. Meanwhile, studying the mechanism of reassortment may accelerate the development of anti-influenza strategies. METHODOLOGY/PRINCIPAL FINDINGS: The hemagglutinin (HA and neuraminidase (NA matching patterns of two pandemic H1N1 viruses (the 1918 and current 2009 strains and a highly pathogenic avian influenza A virus (H5N1 were studied using a pseudotyped particle (pp system. Our data showed that four of the six chimeric HA/NA combinations could produce infectious pps, and that some of the chimeric pps had greater infectivity than did their ancestors, raising the possibility of reassortment among these viruses. The NA of H5N1 (A/Anhui/1/2005 could hardly reassort with the HAs of the two H1N1 viruses. Many biological characteristics of HA and NA, including infectivity, hemagglutinating ability, and NA activity, are dependent on their matching pattern. CONCLUSIONS/SIGNIFICANCE: Our data suggest the existence of an interaction between HA and NA, and the HA NA matching pattern is critical for valid viral reassortment.

  11. Pterodontic Acid Isolated from Laggera pterodonta Inhibits Viral Replication and Inflammation Induced by Influenza A Virus

    Directory of Open Access Journals (Sweden)

    Wenda Guan

    2017-10-01

    Full Text Available Laggera pterodonta (DC. Benth. is a traditional Chinese medicine. The previous study revealed that the crude extracts of this herb could inhibit influenza virus infection, but its anti-influenza components and underlying mechanism of action remain unknown. Column chromatography was performed to isolate components from the plant. Activity against influenza virus of the compound was determined by CPE inhibition assay. Neuraminidase (NA inhibition was measured by chemiluminescence assay. The anti-virus and anti-inflammation effects were determined using dual-luciferase reporter assay, immunofluorescence, quantitative real-time PCR and luminex assay. Pterodontic acid was isolated from L. pterodonta, which showed selective anti-viral activities to H1 subtype of human influenza A virus. Meanwhile, the NA activity was not obviously inhibited by the compound. Further experiments exhibited that the compound can suppress the activation of NF-κB signal pathway and export of viral RNP complexes from the nucleus. In addition, it can significantly attenuate expression of the pro-inflammatory molecules IL-6, MIP-1β, MCP-1, and IP-10 induced by human influenza A virus (H1N1 and similarly downregulate expression of cytokines and chemokines induced by avian influenza A virus (H9N2. This study showed that in vitro antiviral activity of pterodontic acid is most probably associated with inhibiting the replication of influenza A virus by blocking nuclear export of viral RNP complexes, and attenuating the inflammatory response by inhibiting activation of the NF-κB pathway. Pterodontic acid might be a potential antiviral agent against influenza A virus.

  12. Solution structures of potato virus X and narcissus mosaic virus from Raman optical activity

    DEFF Research Database (Denmark)

    Blanch, Ewan W.; Robinson, David J.; Hecht, Lutz

    2002-01-01

    Potato virus X (PVX) and narcissus mosaic virus (NMV) were studied using vibrational Raman optical activity (ROA) in order to obtain new information on the structures of their coat protein subunits. The ROA spectra of the two intact virions are very similar to each other and similar to that of to......Potato virus X (PVX) and narcissus mosaic virus (NMV) were studied using vibrational Raman optical activity (ROA) in order to obtain new information on the structures of their coat protein subunits. The ROA spectra of the two intact virions are very similar to each other and similar......, suggesting that TMV contains less hydrated alpha-helix. Small differences in other spectral regions reflect differences in some loop, turn and side-chain compositions and conformations among the three viruses. A pattern recognition program based on principal component analysis of ROA spectra indicates...

  13. Antimicrobial and antiviral activities against Newcastle disease virus ...

    African Journals Online (AJOL)

    Antimicrobial and antiviral activities against Newcastle disease virus (NDV) from marine algae isolated from Qusier and Marsa-Alam Seashore (Red Sea), Egypt. ... and two filamentous fungi (Aspergillus flavus and Fusarium oxysporum) and against the Newcastle sense Virus (NDV)-(Paramyxoviridae) which is responsible ...

  14. Active Surveillance for Avian Influenza Virus, Egypt, 2010–2012

    Science.gov (United States)

    Kandeil, Ahmed; El-Shesheny, Rabeh; Kayed, Ahmed S.; Gomaa, Mokhtar M.; Maatouq, Asmaa M.; Shehata, Mahmoud M.; Moatasim, Yassmin; Bagato, Ola; Cai, Zhipeng; Rubrum, Adam; Kutkat, Mohamed A.; McKenzie, Pamela P.; Webster, Robert G.; Webby, Richard J.; Ali, Mohamed A.

    2014-01-01

    Continuous circulation of influenza A(H5N1) virus among poultry in Egypt has created an epicenter in which the viruses evolve into newer subclades and continue to cause disease in humans. To detect influenza viruses in Egypt, since 2009 we have actively surveyed various regions and poultry production sectors. From August 2010 through January 2013, >11,000 swab samples were collected; 10% were positive by matrix gene reverse transcription PCR. During this period, subtype H9N2 viruses emerged, cocirculated with subtype H5N1 viruses, and frequently co-infected the same avian host. Genetic and antigenic analyses of viruses revealed that influenza A(H5N1) clade 2.2.1 viruses are dominant and that all subtype H9N2 viruses are G1-like. Cocirculation of different subtypes poses concern for potential reassortment. Avian influenza continues to threaten public and animal health in Egypt, and continuous surveillance for avian influenza virus is needed. PMID:24655395

  15. Enzymes and Enzyme Activity Encoded by Nonenveloped Viruses.

    Science.gov (United States)

    Azad, Kimi; Banerjee, Manidipa; Johnson, John E

    2017-09-29

    Viruses are obligate intracellular parasites that rely on host cell machineries for their replication and survival. Although viruses tend to make optimal use of the host cell protein repertoire, they need to encode essential enzymatic or effector functions that may not be available or accessible in the host cellular milieu. The enzymes encoded by nonenveloped viruses-a group of viruses that lack any lipid coating or envelope-play vital roles in all the stages of the viral life cycle. This review summarizes the structural, biochemical, and mechanistic information available for several classes of enzymes and autocatalytic activity encoded by nonenveloped viruses. Advances in research and development of antiviral inhibitors targeting specific viral enzymes are also highlighted.

  16. Hepatitis A virus: a test method for virucidal activity.

    Science.gov (United States)

    Wolff, M H; Schmitt, J; Rahaus, M; König, A

    2001-08-01

    Hepatitis A virus (HAV) is closely related to the genus enterovirus. HAV is very stable and resistant to acid pH and elevated temperature, as well as to chemicals and environmental influences. Human poliovirus is still one of the model viruses for testing disinfectants but there are discussions about changing to hepatitis A virus. The purpose of this study was to develop a method for using adapted hepatitis A virus to test hand disinfectants. Using HAV strains HM175/24a and FRhK-4 cytopathic effects were visible rarely, and not before 14 days. To verify virus growth in cells a RT-PCR was developed. Two disinfectants tested did not show the required virucidal activity to satisfy current German guidelines.

  17. Antiviral activity of lanatoside C against dengue virus infection.

    Science.gov (United States)

    Cheung, Yan Yi; Chen, Karen Caiyun; Chen, Huixin; Seng, Eng Khuan; Chu, Justin Jang Hann

    2014-11-01

    Dengue infection poses a serious threat globally due to its recent rapid spread and rise in incidence. Currently, there is no approved vaccine or effective antiviral drug for dengue virus infection. In response to the urgent need for the development of an effective antiviral for dengue virus, the US Drug Collection library was screened in this study to identify compounds with anti-dengue activities. Lanatoside C, an FDA approved cardiac glycoside was identified as a candidate anti-dengue compound. Our data revealed that lanatoside C has an IC50 of 0.19μM for dengue virus infection in HuH-7 cells. Dose-dependent reduction in dengue viral RNA and viral proteins synthesis were also observed upon treatment with increasing concentrations of lanatoside C. Time of addition study indicated that lanatoside C inhibits the early processes of the dengue virus replication cycle. Furthermore, lanatoside C can effectively inhibit all four serotypes of dengue virus, flavivirus Kunjin, alphavirus Chikungunya and Sindbis virus as well as the human enterovirus 71. These findings suggest that lanatoside C possesses broad spectrum antiviral activity against several groups of positive-sense RNA viruses. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Passive immunization and active vaccination against Hendra and Nipah viruses.

    Science.gov (United States)

    Broder, C C

    2013-01-01

    Hendra virus and Nipah virus are viral zoonoses first recognized in the mid and late 1990's and are now categorized as the type species of the genus Henipavirus within the family Paramyxoviridae. Their broad species tropism together with their capacity to cause severe and often fatal disease in both humans and animals make Hendra and Nipah "overlap agents" and significant biosecurity threats. The development of effective vaccination strategies to prevent or treat henipavirus infection and disease has been an important area of research. Here, henipavirus active and passive vaccination strategies that have been examined in animal challenge models of Hendra and Nipah virus disease are summarized and discussed.

  19. Heat Shock Protein 70 Modulates Influenza A Virus Polymerase Activity*

    Science.gov (United States)

    Manzoor, Rashid; Kuroda, Kazumichi; Yoshida, Reiko; Tsuda, Yoshimi; Fujikura, Daisuke; Miyamoto, Hiroko; Kajihara, Masahiro; Kida, Hiroshi; Takada, Ayato

    2014-01-01

    The role of heat shock protein 70 (Hsp70) in virus replication has been discussed for many viruses. The known suppressive role of Hsp70 in influenza virus replication is based on studies conducted in cells with various Hsp70 expression levels. In this study, we determined the role of Hsp70 in influenza virus replication in HeLa and HEK293T cells, which express Hsp70 constitutively. Co-immunoprecipitation and immunofluorescence studies revealed that Hsp70 interacted with PB2 or PB1 monomers and PB2/PB1 heterodimer but not with the PB1/PA heterodimer or PB2/PB1/PA heterotrimer and translocated into the nucleus with PB2 monomers or PB2/PB1 heterodimers. Knocking down Hsp70 resulted in reduced virus transcription and replication activities. Reporter gene assay, immunofluorescence assay, and Western blot analysis of nuclear and cytoplasmic fractions from infected cells demonstrated that the increase in viral polymerase activity during the heat shock phase was accompanied with an increase in Hsp70 and viral polymerases levels in the nuclei, where influenza virus replication takes place, whereas a reduction in viral polymerase activity was accompanied with an increase in cytoplasmic relocation of Hsp70 along with viral polymerases. Moreover, significantly higher levels of viral genomic RNA (vRNA) were observed during the heat shock phase than during the recovery phase. Overall, for the first time, these findings suggest that Hsp70 may act as a chaperone for influenza virus polymerase, and the modulatory effect of Hsp70 appears to be a sequel of shuttling of Hsp70 between nuclear and cytoplasmic compartments. PMID:24474693

  20. Viruses and the DNA Damage Response: Activation and Antagonism.

    Science.gov (United States)

    Luftig, Micah A

    2014-11-01

    Viruses must interact with their hosts in order to replicate; these interactions often provoke the evolutionarily conserved response to DNA damage, known as the DNA damage response (DDR). The DDR can be activated by incoming viral DNA, during the integration of retroviruses, or in response to the aberrant DNA structures generated upon replication of DNA viruses. Furthermore, DNA and RNA viral proteins can induce the DDR by promoting inappropriate S phase entry, by modifying cellular DDR factors directly, or by unintentionally targeting host DNA. The DDR may be antiviral, although viruses often require proximal DDR activation of repair and recombination factors to facilitate replication as well as downstream DDR signaling suppression to ensure cell survival. An unintended consequence of DDR attenuation during infection is the long-term survival and proliferation of precancerous cells. Therefore, the molecular basis for DDR activation and attenuation by viruses remains an important area of study that will likely provide key insights into how viruses have evolved with their hosts.

  1. Can vaccinia virus be replaced by MVA virus for testing virucidal activity of chemical disinfectants?

    Directory of Open Access Journals (Sweden)

    Rapp Ingrid

    2010-06-01

    Full Text Available Abstract Background Vaccinia virus strain Lister Elstree (VACV is a test virus in the DVV/RKI guidelines as representative of the stable enveloped viruses. Since the potential risk of laboratory-acquired infections with VACV persists and since the adverse effects of vaccination with VACV are described, the replacement of VACV by the modified vaccinia Ankara strain (MVA was studied by testing the activity of different chemical biocides in three German laboratories. Methods The inactivating properties of different chemical biocides (peracetic acid, aldehydes and alcohols were tested in a quantitative suspension test according to the DVV/RKI guideline. All tests were performed with a protein load of 10% fetal calf serum with both viruses in parallel using different concentrations and contact times. Residual virus was determined by endpoint dilution method. Results The chemical biocides exhibited similar virucidal activity against VACV and MVA. In three cases intra-laboratory differences were determined between VACV and MVA - 40% (v/v ethanol and 30% (v/v isopropanol are more active against MVA, whereas MVA seems more stable than VACV when testing with 0.05% glutardialdehyde. Test accuracy across the three participating laboratories was high. Remarkably inter-laboratory differences in the reduction factor were only observed in two cases. Conclusions Our data provide valuable information for the replacement of VACV by MVA for testing chemical biocides and disinfectants. Because MVA does not replicate in humans this would eliminate the potential risk of inadvertent inoculation with vaccinia virus and disease in non-vaccinated laboratory workers.

  2. A new acyclic heterodinucleotide active against human immunodeficiency virus and herpes simplex virus.

    Science.gov (United States)

    Franchetti, P; Abu Sheikha, G; Cappellacci, L; Marchetti, S; Grifantini, M; Balestra, E; Perno, C; Benatti, U; Brandi, G; Rossi, L; Magnani, M

    2000-09-01

    The most common therapies against human herpes virus (HSV-1) and human immunodeficiency virus (HIV-1) infectivity are based on the administration of nucleoside analogues. Acyclovir (ACV) is the drug of choice against HSV-1 infection, while the acyclic nucleoside phosphonate analogue PMPA has shown marked anti-HIV activity in a phase I and II clinical studies. As monocyte-derived macrophages are assumed to be important as reservoirs of both HSV-1 and HIV-1 infection, new approaches able to inhibit replication of both viruses in macrophages should be welcome. ACVpPMPA, a new heterodinucleotide consisting of both an antiherpetic and an antiretroviral drug bound by a phosphate bridge, was synthesized and encapsulated into autologous erythrocytes modified to increase their phagocytosis by human macrophages. ACVpPMPA-loaded erythrocytes provided an effective in vitro protection against both HSV-1 and HIV-1 replication in human macrophages.

  3. Mechanisms of virus resistance and antiviral activity of snake venoms

    Directory of Open Access Journals (Sweden)

    JVR Rivero

    2011-01-01

    Full Text Available Viruses depend on cell metabolism for their own propagation. The need to foster an intimate relationship with the host has resulted in the development of various strategies designed to help virus escape from the defense mechanisms present in the host. Over millions of years, the unremitting battle between pathogens and their hosts has led to changes in evolution of the immune system. Snake venoms are biological resources that have antiviral activity, hence substances of significant pharmacological value. The biodiversity in Brazil with respect to snakes is one of the richest on the planet; nevertheless, studies on the antiviral activity of venom from Brazilian snakes are scarce. The antiviral properties of snake venom appear as new promising therapeutic alternative against the defense mechanisms developed by viruses. In the current study, scientific papers published in recent years on the antiviral activity of venom from various species of snakes were reviewed. The objective of this review is to discuss the mechanisms of resistance developed by viruses and the components of snake venoms that present antiviral activity, particularly, enzymes, amino acids, peptides and proteins.

  4. RNA polymerase activity of Ustilago maydis virus

    Energy Technology Data Exchange (ETDEWEB)

    Yie, S.W.

    1986-01-01

    Ustilago maydis virus has an RNA polymerase enzyme which is associated with virion capsids. In the presence of Mg/sup 2 +/ ion and ribonucleotide triphosphate, the enzyme catalyzes the in vitro synthesis of mRNA by using dsRNA as a template. The products of the UmV RNA polymerase were both ssRNA and dsRNA. The dsRNA was determined by characteristic mobilities in gel electrophoresis, lack of sensitivity to RNase, and specific hybridization tests. The ssRNAs were identified by elution from a CF-11 column and by their RNase sensitivity. On the basis of the size of ssRNAs, it was concluded that partial transcripts were produced from H dsRNA segments, and full length transcripts were produced from M and L dsRNA segments. The following observations indicates that transcription occurs by strand displacement; (1) Only the positive strand of M2 dsRNA was labeled by the in vitro reaction. (2) The M2 dsRNA which had been labeled with /sup 32/''P-UTP in vitro could be chased from dsRNA with unlabeled UTP. The transcription products of three UmV strains were compared, and the overall pattern of transcription was very similar among them.

  5. Chemical Genomics Identifies the PERK-Mediated Unfolded Protein Stress Response as a Cellular Target for Influenza Virus Inhibition

    Directory of Open Access Journals (Sweden)

    Sara Landeras-Bueno

    2016-04-01

    Full Text Available Influenza A viruses generate annual epidemics and occasional pandemics of respiratory disease with important consequences for human health and the economy. Therefore, a large effort has been devoted to the development of new anti-influenza virus drugs directed to viral targets, as well as to the identification of cellular targets amenable to anti-influenza virus therapy. Here we have addressed the identification of such potential cellular targets by screening collections of drugs approved for human use. We reasoned that screening with a green fluorescent protein-based recombinant replicon system would identify cellular targets involved in virus transcription/replication and/or gene expression and hence address an early stage of virus infection. By using such a strategy, we identified Montelukast (MK as an inhibitor of virus multiplication. MK inhibited virus gene expression but did not alter viral RNA synthesis in vitro or viral RNA accumulation in vivo. The low selectivity index of MK prevented its use as an antiviral, but it was sufficient to identify a new cellular pathway suitable for anti-influenza virus intervention. By deep sequencing of RNA isolated from mock- and virus-infected human cells, treated with MK or left untreated, we showed that it stimulates the PERK-mediated unfolded protein stress response. The phosphorylation of PERK was partly inhibited in virus-infected cells but stimulated in MK-treated cells. Accordingly, pharmacological inhibition of PERK phosphorylation led to increased viral gene expression, while inhibition of PERK phosphatase reduced viral protein synthesis. These results suggest the PERK-mediated unfolded protein response as a potential cellular target to modulate influenza virus infection.

  6. Cytoplasmic ATR Activation Promotes Vaccinia Virus Genome Replication

    Directory of Open Access Journals (Sweden)

    Antonio Postigo

    2017-05-01

    Full Text Available In contrast to most DNA viruses, poxviruses replicate their genomes in the cytoplasm without host involvement. We find that vaccinia virus induces cytoplasmic activation of ATR early during infection, before genome uncoating, which is unexpected because ATR plays a fundamental nuclear role in maintaining host genome integrity. ATR, RPA, INTS7, and Chk1 are recruited to cytoplasmic DNA viral factories, suggesting canonical ATR pathway activation. Consistent with this, pharmacological and RNAi-mediated inhibition of canonical ATR signaling suppresses genome replication. RPA and the sliding clamp PCNA interact with the viral polymerase E9 and are required for DNA replication. Moreover, the ATR activator TOPBP1 promotes genome replication and associates with the viral replisome component H5. Our study suggests that, in contrast to long-held beliefs, vaccinia recruits conserved components of the eukaryote DNA replication and repair machinery to amplify its genome in the host cytoplasm.

  7. Activation of human immunodeficiency virus by ultraviolet radiation

    International Nuclear Information System (INIS)

    Zmudzka, B.Z.; Beer, J.Z.

    1990-01-01

    This article reviews the current status of knowledge about UV-induced HIV activation. A brief description of HIV structure and, in particular, its gene promoter is given. The effects of UVR exposure of cells on HIV activation and HIV promoter induction will be reviewed. Some events that follow production of DNA damage and lead, via activation of an oncogene, to HIV promoter induction will be discussed. Possible consequences of promoter induction and HIV activation for the cell and the virus are mentioned. The review concludes with a discussion of practical aspects and perspectives in this research area. (author)

  8. Influenza virus neuraminidase (NA): a target for antivirals and vaccines.

    Science.gov (United States)

    Jagadesh, Anitha; Salam, Abdul Ajees Abdul; Mudgal, Piya Paul; Arunkumar, Govindakarnavar

    2016-08-01

    Influenza, the most common infectious disease, poses a great threat to human health because of its highly contagious nature and fast transmissibility, often leading to high morbidity and mortality. Effective vaccination strategies may aid in the prevention and control of recurring epidemics and pandemics associated with this infectious disease. However, antigenic shifts and drifts are major concerns with influenza virus, requiring effective global monitoring and updating of vaccines. Current vaccines are standardized primarily based on the amount of hemagglutinin, a major surface antigen, which chiefly constitutes these preparations along with the varying amounts of neuraminidase (NA). Anti-influenza drugs targeting the active site of NA have been in use for more than a decade now. However, NA has not been approved as an effective antigenic component of the influenza vaccine because of standardization issues. Although some studies have suggested that NA antibodies are able to reduce the severity of the disease and induce a long-term and cross-protective immunity, a few major scientific issues need to be addressed prior to launching NA-based vaccines. Interestingly, an increasing number of studies have shown NA to be a promising target for future influenza vaccines. This review is an attempt to consolidate studies that reflect the strength of NA as a suitable vaccine target. The studies discussed in this article highlight NA as a potential influenza vaccine candidate and support taking the process of developing NA vaccines to the next stage.

  9. Alleviative Effects of a Kampo (a Japanese Herbal Medicine “Maoto (Ma-Huang-Tang” on the Early Phase of Influenza Virus Infection and Its Possible Mode of Action

    Directory of Open Access Journals (Sweden)

    Takayuki Nagai

    2014-01-01

    Full Text Available A Kampo medicine, maoto, has been prescribed in an early phase of influenza-like illness and used for a treatment of influenza clinically in Japan these days. However, the efficacy of maoto against the virus infection remains to be elucidated. This study was conducted to evaluate the alleviative effects of maoto against early phase of influenza virus infection and its preliminary mode of actions through immune systems. When maoto (0.9 and 1.6 g/kg/day was orally administered to A/J mice on upper respiratory tract infection of influenza virus A/PR/8/34 from 4 hours to 52 hours postinfection (p.i. significant antipyretic effect was shown in comparison with water-treated control. Administration of maoto (0.8 and 1.3 g/kg/day significantly decreased the virus titers in both nasal (NLF and bronchoalveolar lavage fluids (BALF at 52 hours p.i., and significantly increased the anti-influenza virus IgM, IgA, and IgG1 antibody titers in NLF, BALF, and serum, respectively. Maoto also increased significantly the influenza virus-bound IgG1 and IgM antibody titers in serum and the virus-bound IgM antibody titer in even the BALF of uninfected A/J mice. These results indicate that maoto exerts antipyretic activity in influenza virus-infected mice and virus reducing effect at an early phase of the infection through probably augmentation of the virus-bound natural antibodies.

  10. Influenza Virus Infection, Interferon Response, Viral Counter-Response, and Apoptosis.

    Science.gov (United States)

    Shim, Jung Min; Kim, Jinhee; Tenson, Tanel; Min, Ji-Young; Kainov, Denis E

    2017-08-12

    Human influenza A viruses (IAVs) cause global pandemics and epidemics, which remain serious threats to public health because of the shortage of effective means of control. To combat the surge of viral outbreaks, new treatments are urgently needed. Developing new virus control modalities requires better understanding of virus-host interactions. Here, we describe how IAV infection triggers cellular apoptosis and how this process can be exploited towards the development of new therapeutics, which might be more effective than the currently available anti-influenza drugs.

  11. Mapping the active site of vaccinia virus RNA triphosphatase

    International Nuclear Information System (INIS)

    Gong Chunling; Shuman, Stewart

    2003-01-01

    The RNA triphosphatase component of vaccinia virus mRNA capping enzyme (the product of the viral D1 gene) belongs to a family of metal-dependent phosphohydrolases that includes the RNA triphosphatases of fungi, protozoa, Chlorella virus, and baculoviruses. The family is defined by two glutamate-containing motifs (A and C) that form the metal-binding site. Most of the family members resemble the fungal and Chlorella virus enzymes, which have a complex active site located within the hydrophilic interior of a topologically closed eight-stranded β barrel (the so-called ''triphosphate tunnel''). Here we queried whether vaccinia virus capping enzyme is a member of the tunnel subfamily, via mutational mapping of amino acids required for vaccinia triphosphatase activity. We identified four new essential side chains in vaccinia D1 via alanine scanning and illuminated structure-activity relationships by conservative substitutions. Our results, together with previous mutational data, highlight a constellation of six acidic and three basic amino acids that likely compose the vaccinia triphosphatase active site (Glu37, Glu39, Arg77, Lys107, Glu126, Asp159, Lys161, Glu192, and Glu194). These nine essential residues are conserved in all vertebrate and invertebrate poxvirus RNA capping enzymes. We discerned no pattern of clustering of the catalytic residues of the poxvirus triphosphatase that would suggest structural similarity to the tunnel proteins (exclusive of motifs A and C). We infer that the poxvirus triphosphatases are a distinct lineage within the metal-dependent RNA triphosphatase family. Their unique active site, which is completely different from that of the host cell's capping enzyme, recommends the poxvirus RNA triphosphatase as a molecular target for antipoxviral drug discovery

  12. MAIT cells are activated in acute Dengue virus infection and after in vitro Zika virus infection.

    Science.gov (United States)

    Paquin-Proulx, Dominic; Avelino-Silva, Vivian I; Santos, Bianca A N; Silveira Barsotti, Nathália; Siroma, Fabiana; Fernandes Ramos, Jessica; Coracini Tonacio, Adriana; Song, Alice; Maestri, Alvino; Barros Cerqueira, Natalia; Felix, Alvina Clara; Levi, José Eduardo; Greenspun, Benjamin C; de Mulder Rougvie, Miguel; Rosenberg, Michael G; Nixon, Douglas F; Kallas, Esper G

    2018-01-01

    Dengue virus (DENV) and Zika virus (ZIKV) are members of the Flaviviridae and are predominantly transmitted via mosquito bites. Both viruses are responsible for a growing number of infections in tropical and subtropical regions. DENV infection can cause lethargy with severe morbidity and dengue shock syndrome leading to death in some cases. ZIKV is now linked with Guillain-Barré syndrome and fetal malformations including microcephaly and developmental disorders (congenital Zika syndrome). The protective and pathogenic roles played by the immune response in these infections is unknown. Mucosal-associated invariant T (MAIT) cells are a population of innate T cells with potent anti-bacterial activity. MAIT cells have also been postulated to play a role in the immune response to viral infections. In this study, we evaluated MAIT cell frequency, phenotype, and function in samples from subjects with acute and convalescent DENV infection. We found that in acute DENV infection, MAIT cells had elevated co-expression of the activation markers CD38 and HLA-DR and had a poor IFNγ response following bacterial stimulation. Furthermore, we found that MAIT cells can produce IFNγ in response to in vitro infection with ZIKV. This MAIT cell response was independent of MR1, but dependent on IL-12 and IL-18. Our results suggest that MAIT cells may play an important role in the immune response to Flavivirus infections.

  13. MAIT cells are activated in acute Dengue virus infection and after in vitro Zika virus infection.

    Directory of Open Access Journals (Sweden)

    Dominic Paquin-Proulx

    2018-01-01

    Full Text Available Dengue virus (DENV and Zika virus (ZIKV are members of the Flaviviridae and are predominantly transmitted via mosquito bites. Both viruses are responsible for a growing number of infections in tropical and subtropical regions. DENV infection can cause lethargy with severe morbidity and dengue shock syndrome leading to death in some cases. ZIKV is now linked with Guillain-Barré syndrome and fetal malformations including microcephaly and developmental disorders (congenital Zika syndrome. The protective and pathogenic roles played by the immune response in these infections is unknown. Mucosal-associated invariant T (MAIT cells are a population of innate T cells with potent anti-bacterial activity. MAIT cells have also been postulated to play a role in the immune response to viral infections. In this study, we evaluated MAIT cell frequency, phenotype, and function in samples from subjects with acute and convalescent DENV infection. We found that in acute DENV infection, MAIT cells had elevated co-expression of the activation markers CD38 and HLA-DR and had a poor IFNγ response following bacterial stimulation. Furthermore, we found that MAIT cells can produce IFNγ in response to in vitro infection with ZIKV. This MAIT cell response was independent of MR1, but dependent on IL-12 and IL-18. Our results suggest that MAIT cells may play an important role in the immune response to Flavivirus infections.

  14. Antiviral activity of maca (Lepidium meyenii) against human influenza virus.

    Science.gov (United States)

    Del Valle Mendoza, Juana; Pumarola, Tomàs; Gonzales, Libertad Alzamora; Del Valle, Luis J

    2014-09-01

    To investigate antiviral activity of maca to reduce viral load in Madin-Darby canine kidney (MDCK) cells infected with influenza type A and B viruses (Flu-A and Flu-B, respectively). Maca were extracted with methanol (1:2, v/v). The cell viability and toxicity of the extracts were evaluated on MDCK cells using method MTT assay. Antiviral activity of compounds against Flu-A and Flu-B viruses was assayed using a test for determining the inhibition of the cytopathic effect on cell culture and multiplex RT-PCR. The methanol extract of maca showed low cytotoxicity and inhibited influenza-induced cytopathic effect significantly, while viral load was reduced via inhibition of viral growth in MDCK infected cells. Maca contains potent inhibitors of Flu-A and Flu-B with a selectivity index [cytotoxic concentration 50%/IC50] of 157.4 and 110.5, respectively. In vitro assays demonstrated that maca has antiviral activity not only against Flu-A (like most antiviral agents) but also Flu-B viruses, providing remarkable therapeutic benefits. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  15. Altered specificity of single-chain antibody fragments bound to pandemic H1N1-2009 influenza virus after conversion of the phage-bound to the soluble form

    OpenAIRE

    Kaku, Yoshihiro; Noguchi, Akira; Okutani, Akiko; Inoue, Satoshi; Tanabayashi, Kiyoshi; Yamamoto, Yoshie; Hotta, Akitoyo; Suzuki, Michio; Sugiura, Naoko; Yamada, Akio

    2012-01-01

    Abstract Background In 2009, a novel influenza A/H1N1 virus (H1N1pdm) quickly spread worldwide and co-circulated with then-existing seasonal H1N1 virus (sH1N1). Distinguishing between these 2 viruses was necessary to better characterize the epidemiological properties of the emergent virus, including transmission patterns, pathogenesis, and anti-influenza drug resistance. This situation prompted us to develop a point-of-care virus differentiation system before entering the 2009–2010 influenza ...

  16. Screening for Neuraminidase Inhibitory Activity in Traditional Chinese Medicines Used to Treat Influenza.

    Science.gov (United States)

    Yang, Xian-Ying; Liu, Ai-Lin; Liu, Shu-Jing; Xu, Xiao-Wei; Huang, Lin-Fang

    2016-08-27

    To screen for influenza virus neuraminidase inhibition and to provide a reference for the clinical treatment of influenza using traditional Chinese medicines (TCM). In this study, 421 crude extracts (solubilized with petroleum ether, ethanol, ethyl acetate, and aqueous solvents) were obtained from 113 TCM. The medicine extracts were then reacted with oseltamivir, using 2'-(4-methylumbelliferyl)-α-D-N-acetylneuraminic acid (MUNANA) as the substrate, to determine influenza virus neuraminidase activity using a standard fluorimetric assay. It was found that Chinese medicine extracts from Pyrola calliantha, Cynanchum wilfordii, Balanophora involucrata and Paeonia delavayi significantly inhibited neuraminidase activity at a concentration of 40 μg/mL. Dose-dependent inhibitory assays also revealed significant inhibition. The IC50 range of the TCM extracts for influenza virus neuraminidase was approximately 12.66-34.85 μg/mL, respectively. Some Chinese medicines have clear anti-influenza viral effects that may play an important role in the treatment of influenza through the inhibition of viral neuraminidase. The results of this study demonstrated that plant medicines can serve as a useful source of neuraminidase (NA) inhibitors and further investigation into the pharmacologic activities of these extracts is warranted.

  17. Elicitation of Protective Antibodies against a Broad Panel of H1N1 Viruses in Ferrets Preimmune to Historical H1N1 Influenza Viruses.

    Science.gov (United States)

    Carter, Donald M; Darby, Christopher A; Johnson, Scott K; Carlock, Michael A; Kirchenbaum, Greg A; Allen, James D; Vogel, Thorsten U; Delagrave, Simon; DiNapoli, Joshua; Kleanthous, Harold; Ross, Ted M

    2017-12-15

    -lasting protective immune responses. The goal of these vaccines is to stimulate immune responses that react against most, if not all, circulating influenza strains, over a long period of time in all populations of people. Commonly, these experimental vaccines are tested in naive animal models that do not have anti-influenza immune responses; however, humans have preexisting immunity to influenza viral antigens, particularly antibodies to the HA and NA glycoproteins. Therefore, this study investigated how preexisting antibodies to historical influenza viruses influenced HAI-specific antibodies and protective efficacy using a broadly protective vaccine candidate. Copyright © 2017 American Society for Microbiology.

  18. Mouse lung slices: An ex vivo model for the evaluation of antiviral and anti-inflammatory agents against influenza viruses.

    Science.gov (United States)

    Liu, Rui; An, Liwei; Liu, Ge; Li, Xiaoyu; Tang, Wei; Chen, Xulin

    2015-08-01

    The influenza A virus is notoriously known for its ability to cause recurrent epidemics and global pandemics. Antiviral therapy is effective when treatment is initiated within 48h of symptom onset, and delaying treatment beyond this time frame is associated with decreased efficacy. Research on anti-inflammatory therapy to ameliorate influenza-induced inflammation is currently underway and seems important to the impact on the clinical outcome. Both antiviral and anti-inflammatory drugs with novel mechanisms of action are urgently needed. Current methods for evaluating the efficacy of anti-influenza drugs rely mostly on transformed cells and animals. Transformed cell models are distantly related to physiological and pathological conditions. Although animals are the best choices for preclinical drug testing, they are not time- or cost-efficient. In this study, we established an ex vivo model using mouse lung slices to evaluate both antiviral and anti-inflammatory agents against influenza virus infection. Both influenza virus PR8 (H1N1) and A/Human/Hubei/3/2005 (H3N2) can replicate efficiently in mouse lung slices and trigger significant cytokine and chemokine responses. The induction of selected cytokines and chemokines were found to have a positive correlation between ex vivo and in vivo experiments, suggesting that the ex vivo cultured lung slices may closely resemble the lung functionally in an in vivo configuration when challenged by influenza virus. Furthermore, a set of agents with known antiviral and/or anti-inflammatory activities were tested to validate the ex vivo model. Our results suggested that mouse lung slices provide a robust, convenient and cost-efficient model for the assessment of both antiviral and anti-inflammatory agents against influenza virus infection in one assay. This ex vivo model may predict the efficacy of drug candidates' antiviral and anti-inflammatory activities in vivo. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Antiviral activity of glycyrrhizin against hepatitis C virus in vitro.

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    Yoshihiro Matsumoto

    Full Text Available Glycyrrhizin (GL has been used in Japan to treat patients with chronic viral hepatitis, as an anti-inflammatory drug to reduce serum alanine aminotransferase levels. GL is also known to exhibit various biological activities, including anti-viral effects, but the anti-hepatitis C virus (HCV effect of GL remains to be clarified. In this study, we demonstrated that GL treatment of HCV-infected Huh7 cells caused a reduction of infectious HCV production using cell culture-produced HCV (HCVcc. To determine the target step in the HCV lifecycle of GL, we used HCV pseudoparticles (HCVpp, replicon, and HCVcc systems. Significant suppressions of viral entry and replication steps were not observed. Interestingly, extracellular infectivity was decreased, and intracellular infectivity was increased. By immunofluorescence and electron microscopic analysis of GL treated cells, HCV core antigens and electron-dense particles had accumulated on endoplasmic reticulum attached to lipid droplet (LD, respectively, which is thought to act as platforms for HCV assembly. Furthermore, the amount of HCV core antigen in LD fraction increased. Taken together, these results suggest that GL inhibits release of infectious HCV particles. GL is known to have an inhibitory effect on phospholipase A2 (PLA2. We found that group 1B PLA2 (PLA2G1B inhibitor also decreased HCV release, suggesting that suppression of virus release by GL treatment may be due to its inhibitory effect on PLA2G1B. Finally, we demonstrated that combination treatment with GL augmented IFN-induced reduction of virus in the HCVcc system. GL is identified as a novel anti-HCV agent that targets infectious virus particle release.

  20. The cap-snatching endonuclease of influenza virus polymerase resides in the PA subunit.

    Science.gov (United States)

    Dias, Alexandre; Bouvier, Denis; Crépin, Thibaut; McCarthy, Andrew A; Hart, Darren J; Baudin, Florence; Cusack, Stephen; Ruigrok, Rob W H

    2009-04-16

    The influenza virus polymerase, a heterotrimer composed of three subunits, PA, PB1 and PB2, is responsible for replication and transcription of the eight separate segments of the viral RNA genome in the nuclei of infected cells. The polymerase synthesizes viral messenger RNAs using short capped primers derived from cellular transcripts by a unique 'cap-snatching' mechanism. The PB2 subunit binds the 5' cap of host pre-mRNAs, which are subsequently cleaved after 10-13 nucleotides by the viral endonuclease, hitherto thought to reside in the PB2 (ref. 5) or PB1 (ref. 2) subunits. Here we describe biochemical and structural studies showing that the amino-terminal 209 residues of the PA subunit contain the endonuclease active site. We show that this domain has intrinsic RNA and DNA endonuclease activity that is strongly activated by manganese ions, matching observations reported for the endonuclease activity of the intact trimeric polymerase. Furthermore, this activity is inhibited by 2,4-dioxo-4-phenylbutanoic acid, a known inhibitor of the influenza endonuclease. The crystal structure of the domain reveals a structural core closely resembling resolvases and type II restriction endonucleases. The active site comprises a histidine and a cluster of three acidic residues, conserved in all influenza viruses, which bind two manganese ions in a configuration similar to other two-metal-dependent endonucleases. Two active site residues have previously been shown to specifically eliminate the polymerase endonuclease activity when mutated. These results will facilitate the optimisation of endonuclease inhibitors as potential new anti-influenza drugs.

  1. Identification of covalent active site inhibitors of dengue virus protease

    Directory of Open Access Journals (Sweden)

    Koh-Stenta X

    2015-12-01

    Full Text Available Xiaoying Koh-Stenta,1 Joma Joy,1 Si Fang Wang,1 Perlyn Zekui Kwek,1 John Liang Kuan Wee,1 Kah Fei Wan,2 Shovanlal Gayen,1 Angela Shuyi Chen,1 CongBao Kang,1 May Ann Lee,1 Anders Poulsen,1 Subhash G Vasudevan,3 Jeffrey Hill,1 Kassoum Nacro11Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR, Singapore; 2Novartis Institute for Tropical Diseases, Singapore; 3Program in Emerging Infectious Diseases, Duke-NUS Graduate Medical School, SingaporeAbstract: Dengue virus (DENV protease is an attractive target for drug development; however, no compounds have reached clinical development to date. In this study, we utilized a potent West Nile virus protease inhibitor of the pyrazole ester derivative class as a chemical starting point for DENV protease drug development. Compound potency and selectivity for DENV protease were improved through structure-guided small molecule optimization, and protease-inhibitor binding interactions were validated biophysically using nuclear magnetic resonance. Our work strongly suggests that this class of compounds inhibits flavivirus protease through targeted covalent modification of active site serine, contrary to an allosteric binding mechanism as previously described.Keywords: flavivirus protease, small molecule optimization, covalent inhibitor, active site binding, pyrazole ester derivatives

  2. Antiviral activity of stachyflin on influenza A viruses of different hemagglutinin subtypes.

    Science.gov (United States)

    Motohashi, Yurie; Igarashi, Manabu; Okamatsu, Masatoshi; Noshi, Takeshi; Sakoda, Yoshihiro; Yamamoto, Naoki; Ito, Kimihito; Yoshida, Ryu; Kida, Hiroshi

    2013-04-16

    The hemagglutinin (HA) of influenza viruses is a possible target for antiviral drugs because of its key roles in the initiation of infection. Although it was found that a natural compound, Stachyflin, inhibited the growth of H1 and H2 but not H3 influenza viruses in MDCK cells, inhibitory activity of the compound has not been assessed against H4-H16 influenza viruses and the precise mechanism of inhibition has not been clarified. Inhibitory activity of Stachyflin against H4-H16 influenza viruses, as well as H1-H3 viruses was examined in MDCK cells. To identify factors responsible for the susceptibility of the viruses to this compound, Stachyflin-resistant viruses were selected in MDCK cells and used for computer docking simulation. It was found that in addition to antiviral activity of Stachyflin against influenza viruses of H1 and H2 subtypes, it inhibited replication of viruses of H5 and H6 subtypes, as well as A(H1N1)pdm09 virus in MDCK cells. Stachyflin also inhibited the virus growth in the lungs of mice infected with A/WSN/1933 (H1N1) and A/chicken/Ibaraki/1/2005 (H5N2). Substitution of amino acid residues was found on the HA2 subunit of Stachyflin-resistant viruses. Docking simulation indicated that D37, K51, T107, and K121 are responsible for construction of the cavity for the binding of the compound. In addition, 3-dimensional structure of the cavity of the HA of Stachyflin-susceptible virus strains was different from that of insusceptible virus strains. Antiviral activity of Stachyflin was found against A(H1N1)pdm09, H5, and H6 viruses, and identified a potential binding pocket for Stachyflin on the HA. The present results should provide us with useful information for the development of HA inhibitors with more effective and broader spectrum.

  3. Synthesis and antiviral activity of PB1 component of the influenza A RNA polymerase peptide fragments.

    Science.gov (United States)

    Matusevich, O V; Egorov, V V; Gluzdikov, I A; Titov, M I; Zarubaev, V V; Shtro, A A; Slita, A V; Dukov, M I; Shurygina, A-P S; Smirnova, T D; Kudryavtsev, I V; Vasin, A V; Kiselev, O I

    2015-01-01

    This study is devoted to the antiviral activity of peptide fragments from the PB1 protein - a component of the influenza A RNA polymerase. The antiviral activity of the peptides synthesized was studied in MDCK cell cultures against the pandemic influenza strain A/California/07/2009 (H1N1) pdm09. We found that peptide fragments 6-13, 6-14, 26-30, 395-400, and 531-540 of the PB1 protein were capable of suppressing viral replication in cell culture. Terminal modifications i.e. N-acetylation and C-amidation increased the antiviral properties of the peptides significantly. Peptide PB1 (6-14) with both termini modified showed maximum antiviral activity, its inhibitory activity manifesting itself during the early stages of viral replication. It was also shown that the fluorescent-labeled analog of this peptide was able to penetrate into the cell. The broad range of virus-inhibiting activity of PB1 (6-14) peptide was confirmed using a panel of influenza A viruses of H1, H3 and H5 subtypes including those resistant to oseltamivir, the leading drug in anti-influenza therapy. Thus, short peptide fragments of the PB1 protein could serve as leads for future development of influenza prevention and/or treatment agents. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Activation mechanisms of natural killer cells during influenza virus infection.

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    Ilwoong Hwang

    Full Text Available During early viral infection, activation of natural killer (NK cells elicits the effector functions of target cell lysis and cytokine production. However, the cellular and molecular mechanisms leading to NK cell activation during viral infections are incompletely understood. In this study, using a model of acute viral infection, we investigated the mechanisms controlling cytotoxic activity and cytokine production in response to influenza (flu virus. Analysis of cytokine receptor deficient mice demonstrated that type I interferons (IFNs, but not IL-12 or IL-18, were critical for the NK cell expression of both IFN-γ and granzyme B in response to flu infection. Further, adoptive transfer experiments revealed that NK cell activation was mediated by type I IFNs acting directly on NK cells. Analysis of signal transduction molecules showed that during flu infection, STAT1 activation in NK cells was completely dependent on direct type I IFN signaling, whereas STAT4 activation was only partially dependent. In addition, granzyme B induction in NK cells was mediated by signaling primarily through STAT1, but not STAT4, while IFN-γ production was mediated by signaling through STAT4, but not STAT1. Therefore, our findings demonstrate the importance of direct action of type I IFNs on NK cells to mount effective NK cell responses in the context of flu infection and delineate NK cell signaling pathways responsible for controlling cytotoxic activity and cytokine production.

  5. Mouse Saliva Inhibits Transit of Influenza Virus to the Lower Respiratory Tract by Efficiently Blocking Influenza Virus Neuraminidase Activity.

    Science.gov (United States)

    Gilbertson, Brad; Ng, Wy Ching; Crawford, Simon; McKimm-Breschkin, Jenny L; Brown, Lorena E

    2017-07-15

    We previously identified a novel inhibitor of influenza virus in mouse saliva that halts the progression of susceptible viruses from the upper to the lower respiratory tract of mice in vivo and neutralizes viral infectivity in MDCK cells. Here, we investigated the viral target of the salivary inhibitor by using reverse genetics to create hybrid viruses with some surface proteins derived from an inhibitor-sensitive strain and others from an inhibitor-resistant strain. These viruses demonstrated that the origin of the viral neuraminidase (NA), but not the hemagglutinin or matrix protein, was the determinant of susceptibility to the inhibitor. Comparison of the NA sequences of a panel of H3N2 viruses with differing sensitivities to the salivary inhibitor revealed that surface residues 368 to 370 (N2 numbering) outside the active site played a key role in resistance. Resistant viruses contained an EDS motif at this location, and mutation to either EES or KDS, found in highly susceptible strains, significantly increased in vitro susceptibility to the inhibitor and reduced the ability of the virus to progress to the lungs when the viral inoculum was initially confined to the upper respiratory tract. In the presence of saliva, viral strains with a susceptible NA could not be efficiently released from the surfaces of infected MDCK cells and had reduced enzymatic activity based on their ability to cleave substrate in vitro This work indicates that the mouse has evolved an innate inhibitor similar in function, though not in mechanism, to what humans have created synthetically as an antiviral drug for influenza virus. IMPORTANCE Despite widespread use of experimental pulmonary infection of the laboratory mouse to study influenza virus infection and pathogenesis, to our knowledge, mice do not naturally succumb to influenza. Here, we show that mice produce their own natural form of neuraminidase inhibitor in saliva that stops the virus from reaching the lungs, providing a

  6. Pseudorabies virus infection alters neuronal activity and connectivity in vitro.

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    Kelly M McCarthy

    2009-10-01

    Full Text Available Alpha-herpesviruses, including human herpes simplex virus 1 & 2, varicella zoster virus and the swine pseudorabies virus (PRV, infect the peripheral nervous system of their hosts. Symptoms of infection often include itching, numbness, or pain indicative of altered neurological function. To determine if there is an in vitro electrophysiological correlate to these characteristic in vivo symptoms, we infected cultured rat sympathetic neurons with well-characterized strains of PRV known to produce virulent or attenuated symptoms in animals. Whole-cell patch clamp recordings were made at various times after infection. By 8 hours of infection with virulent PRV, action potential (AP firing rates increased substantially and were accompanied by hyperpolarized resting membrane potentials and spikelet-like events. Coincident with the increase in AP firing rate, adjacent neurons exhibited coupled firing events, first with AP-spikelets and later with near identical resting membrane potentials and AP firing. Small fusion pores between adjacent cell bodies formed early after infection as demonstrated by transfer of the low molecular weight dye, Lucifer Yellow. Later, larger pores formed as demonstrated by transfer of high molecular weight Texas red-dextran conjugates between infected cells. Further evidence for viral-induced fusion pores was obtained by infecting neurons with a viral mutant defective for glycoprotein B, a component of the viral membrane fusion complex. These infected neurons were essentially identical to mock infected neurons: no increased AP firing, no spikelet-like events, and no electrical or dye transfer. Infection with PRV Bartha, an attenuated circuit-tracing strain delayed, but did not eliminate the increased neuronal activity and coupling events. We suggest that formation of fusion pores between infected neurons results in electrical coupling and elevated firing rates, and that these processes may contribute to the altered neural

  7. [Antiviral activity of different drugs in vitro against viruses of bovine infectious rhinotracheitis and bovine diarrhea].

    Science.gov (United States)

    Glotov, A G; Glotova, T I; Sergeev, A A; Belkina, T V; Sergeev, A N

    2004-01-01

    In vitro experiments studied the antiviral activity of 11 different drugs against viruses of bovine infective rhinotracheitis (BIRT) and bovine viral diarrhea (BVD). The 50% inhibiting concentrations of the test agents were determined in the monolayers of MDBK and KCT cell cultures. Only did phosprenyl show a virucidal activity against BIRT virus. All the tested drugs significantly inhibited the reproduction of BIRT virus in the sensitive MDBK cell cultures. Thus, bromuridin, acyclovir, ribavirin and methisazonum inhibited the virus by > or = 100,000 times; liposomal ribavirin, gossypolum, anandinum, polyprenolum, phosprenyl, by 1000-10,000 times; eracond and argovit, by 100 times. In experiments on BVD virus, the cultured KCT cells displayed the antiviral activity of bromuridin, phosprenil, polyprenolum, methisazonum, acyclovir, gossypolum, argovit, and ribavirin (in two variants), which caused a statistically significant (100-10,000-fold) decrease in the productive activity of this virus. Eracond and anandid proved to be ineffective.

  8. Use of Cellular Decapping Activators by Positive-Strand RNA Viruses

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    Jennifer Jungfleisch

    2016-12-01

    Full Text Available Positive-strand RNA viruses have evolved multiple strategies to not only circumvent the hostile decay machinery but to trick it into being a priceless collaborator supporting viral RNA translation and replication. In this review, we describe the versatile interaction of positive-strand RNA viruses and the 5′-3′ mRNA decay machinery with a focus on the viral subversion of decapping activators. This highly conserved viral trickery is exemplified with the plant Brome mosaic virus, the animal Flock house virus and the human hepatitis C virus.

  9. Mutations that abrogate transactivational activity of the feline leukemia virus long terminal repeat do not affect virus replication

    International Nuclear Information System (INIS)

    Abujamra, Ana L.; Faller, Douglas V.; Ghosh, Sajal K.

    2003-01-01

    The U3 region of the LTR of oncogenic Moloney murine leukemia virus (Mo-MuLV) and feline leukemia viruses (FeLV) have been previously reported to activate expression of specific cellular genes in trans, such as MHC class I, collagenase IV, and MCP-1, in an integration-independent manner. It has been suggested that transactivation of these specific cellular genes by leukemia virus U3-LTR may contribute to the multistage process of leukemogenesis. The U3-LTR region, necessary for gene transactivational activity, also contains multiple transcription factor-binding sites that are essential for normal virus replication. To dissect the promoter activity and the gene transactivational activity of the U3-LTR, we conducted mutational analysis of the U3-LTR region of FeLV-A molecular clone 61E. We identified minimal nucleotide substitution mutants on the U3 LTR that did not disturb transcription factor-binding sites but abrogated its ability to transactivate the collagenase gene promoter. To determine if these mutations actually have altered any uncharacterized important transcription factor-binding site, we introduced these U3-LTR mutations into the full-length infectious molecular clone 61E. We demonstrate that the mutant virus was replication competent but could not transactivate cellular gene expression. These results thus suggest that the gene transactivational activity is a distinct property of the LTR and possibly not related to its promoter activity. The cellular gene transactivational activity-deficient mutant FeLV generated in this study may also serve as a valuable reagent for testing the biological significance of LTR-mediated cellular gene activation in the tumorigenesis caused by leukemia viruses

  10. Neutralizing activities of human immunoglobulin derived from donors in Japan against mosquito-borne flaviviruses, Japanese encephalitis virus, West Nile virus, and dengue virus

    Directory of Open Access Journals (Sweden)

    Yunoki M

    2016-07-01

    Full Text Available Mikihiro Yunoki,1-3 Takeshi Kurosu,2 Ritsuko Kubota Koketsu,2,4 Kazuo Takahashi,5 Yoshinobu Okuno,4 Kazuyoshi Ikuta2,4 1Research and Development Division, Japan Blood Products Organization, Tokyo, 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 3Pathogenic Risk Evaluation, Graduate School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, 4Research and Development Division, The Research Foundation for Microbial Diseases of Osaka University, Kagawa, 5Osaka Prefectural Institute of Public Health, Osaka, Japan Abstract: Japanese encephalitis virus (JEV, West Nile virus (WNV, and dengue virus (DenV are causal agents of Japanese encephalitis, West Nile fever, and dengue fever, respectively. JEV is considered to be indigenized and widespread in Japan, whereas WNV and DenV are not indigenized in Japan. Globulin products seem to reflect the status of the donor population according to antivirus neutralization activity. However, the anti-JEV, -WNV, and -DenV neutralization activities of globulin products derived from donors in Japan have not been clarified. Furthermore, potential candidates for the development of an effective immunotherapeutic drug for encephalitis caused by JEV, WNV, or DenV have also not been identified. Therefore, the aim of this study was to determine the overall status of the donor population in Japan based on globulin products by evaluating anti-JEV, -WNV, and -DenV neutralizing activities of intravenous immunoglobulin. Overall, intravenous immunoglobulin products showed stable neutralizing activity against JEV but showed no or only weak activity against WNV or DenV. These results suggest that the epidemiological level against WNV and DenV in the donor population of Japan is still low, suggesting that these viruses are not yet indigenized. In addition, JEV vaccinations and/or infections in the donor population do not induce a cross-reactive antibody against WNV. Keywords

  11. Some Surface-Active Agents and Their Virucidal Effect on Foot-and-Mouth Disease Virus

    Science.gov (United States)

    Fellowes, O. N.

    1965-01-01

    Selected cationic and anionic surface-active compounds were tested to determine their virucidal effect on the foot-and-mouth disease virus, type O, strain M11, propagated in primary calf kidney cells. The chemical inactivation of the virus was tested with 0.5, 1.0, 2.0, and 5.0% concentrations of the selected compounds. Virus controls with pH adjusted to cover the expected range of the mixtures of the chemicals and virus were also tested. The absence of virus from the mixtures of chemical and virus after reaction at 28 C for 2 hr was assayed by inoculating suckling mice with the mixtures. One cationic compound, alkyl methyl isoquinilinium chloride, showed considerable antiviral activity due largely to pH effect. The use of the surface-active agents investigated in this study, in the presence of organic material, would not be recommended as virucides. PMID:4286396

  12. Virus-specific cytotoxic T cells in chronic active Epstein-Barr virus infection.

    Science.gov (United States)

    Shibayama, Haruna; Imadome, Ken-Ichi; Onozawa, Erika; Tsuzura, Akiho; Miura, Osamu; Koyama, Takatoshi; Arai, Ayako

    2017-01-01

    Chronic active Epstein-Barr virus infection (CAEBV) is a disease characterized by clonally proliferating and activated EBV-infected T or NK cells accompanied by chronic inflammation and T- or NK-cell neoplasms. However, the mechanism for developing CAEBV has not been clarified to date. Because the decreased number or inactivation of EBV-specific cytotoxic T lymphocytes (CTLs) resulted in the development of EBV-positive B-cell neoplasms, we investigated the number of CTLs in CAEBV patients using the tetrameric complexes of HLA-restricted EBV-specific peptides. Among the seven patients examined, EBV-specific CTLs were detected in the peripheral blood mononuclear cells (PBMCs) of four cases but were not detected in three cases. The ratio of EBV-specific CTLs in PBMCs tended to be higher in the patients with active disease than in those with inactive disease. In two patients in whom EBV-specific CTLs had not been detected, CTLs appeared after the eradication of EBV-infected T cells by allogeneic bone marrow transplantation. These results suggested that the failure of CTLs had a role in developing CAEBV, although the induction number and function of EBV-specific CTLs might vary in each patient.

  13. Effect of neuraminidase inhibitor-resistant mutations on pathogenicity of clade 2.2 A/Turkey/15/06 (H5N1 influenza virus in ferrets.

    Directory of Open Access Journals (Sweden)

    Natalia A Ilyushina

    2010-05-01

    virulence in mammalian hosts compared to drug-sensitive viruses. There is a need for novel anti-influenza drugs that target different virus/host factors and can limit the emergence of resistance.

  14. HIV eradication: combinatorial approaches to activate latent viruses.

    Science.gov (United States)

    De Crignis, Elisa; Mahmoudi, Tokameh

    2014-11-21

    The concept of eradication of the Human Immune Deficiency Virus (HIV) from infected patients has gained much attention in the last few years. While combination Anti-Retroviral Therapy (c-ART) has been extremely effective in suppressing viral replication, it is not curative. This is due to the presence of a reservoir of latent HIV infected cells, which persist in the presence of c-ART. Recently, pharmaceutical approaches have focused on the development of molecules able to induce HIV-1 replication from latently infected cells in order to render them susceptible to viral cytopathic effects and host immune responses. Alternative pathways and transcription complexes function to regulate the activity of the HIV promoter and might serve as molecular targets for compounds to activate latent HIV. A combined therapy coupling various depressors and activators will likely be the most effective in promoting HIV replication while avoiding pleiotropic effects at the cellular level. Moreover, in light of differences among HIV subtypes and variability in integration sites, the combination of multiple agents targeting multiple pathways will increase likelihood of therapeutic effectiveness and prevent mutational escape. This review provides an overview of the mechanisms that can be targeted to induce HIV activation focusing on potential combinatorial approaches.

  15. MAIT cells are activated in acute Dengue virus infection and after in vitro Zika virus infection

    OpenAIRE

    Paquin-Proulx, Dominic; Avelino-Silva, Vivian I.; Santos, Bianca A. N.; Silveira Barsotti, Nathália; Siroma, Fabiana; Fernandes Ramos, Jessica; Coracini Tonacio, Adriana; Song, Alice; Maestri, Alvino; Barros Cerqueira, Natalia; Felix, Alvina Clara; Levi, José Eduardo; Greenspun, Benjamin C.; de Mulder Rougvie, Miguel; Rosenberg, Michael G.

    2018-01-01

    Dengue virus (DENV) and Zika virus (ZIKV) are members of the Flaviviridae and are predominantly transmitted via mosquito bites. Both viruses are responsible for a growing number of infections in tropical and subtropical regions. DENV infection can cause lethargy with severe morbidity and dengue shock syndrome leading to death in some cases. ZIKV is now linked with Guillain-Barré syndrome and fetal malformations including microcephaly and developmental disorders (congenital Zika syndrome). The...

  16. MAIT cells are activated in acute Dengue virus infection and after in vitro Zika virus infection.

    OpenAIRE

    Dominic Paquin-Proulx; Vivian I Avelino-Silva; Bianca A N Santos; Nathália Silveira Barsotti; Fabiana Siroma; Jessica Fernandes Ramos; Adriana Coracini Tonacio; Alice Song; Alvino Maestri; Natalia Barros Cerqueira; Alvina Clara Felix; José Eduardo Levi; Benjamin C Greenspun; Miguel de Mulder Rougvie; Michael G Rosenberg

    2018-01-01

    Dengue virus (DENV) and Zika virus (ZIKV) are members of the Flaviviridae and are predominantly transmitted via mosquito bites. Both viruses are responsible for a growing number of infections in tropical and subtropical regions. DENV infection can cause lethargy with severe morbidity and dengue shock syndrome leading to death in some cases. ZIKV is now linked with Guillain-Barré syndrome and fetal malformations including microcephaly and developmental disorders (congenital Zika syndrome). The...

  17. Antiviral activity of A771726, the active metabolite of leflunomide, against Junín virus.

    Science.gov (United States)

    Sepúlveda, Claudia S; García, Cybele C; Damonte, Elsa B

    2018-05-01

    The aim of this study was to investigate the effect of A771726, the active metabolite of leflunomide, (CONICET-UBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad against the infection with Junín virus (JUNV), agent of Argentine hemorrhagic fever (AHF). The treatment with non-cytotoxic concentrations of A771726 of Vero and A549 cells infected with JUNV inhibited virus replication in a dose-dependent manner, as determined by virus yield reduction assay. The antiviral effectiveness of A771726 was not importantly affected by the multiplicity of infection and the virus strain. Moreover, the combination of A771726 and ribavirin had a significantly more potent antiviral activity than each single drug treatment. Mechanistic studies showed that the main action of A771726 is exerted before 6 h of JUNV infection. Accordingly, inhibition of viral RNA synthesis was detected in treated infected cells by real time RT-PCR. The exogenous addition of uridine or orotic acid produced a partial reversal of the inhibitory effect of A771726 on infective virus production whereas a total reversion was detected on JUNV RNA synthesis, probably by restoration of the enzymatic activity of dihydroorotate dehydrogenase (DHODH) and the intracellular pyrimidine pools. In conclusion, these results suggest that the antiviral target would be viral RNA synthesis through pyrimidine depletion, but any other effect of the compound on JUNV infection cannot be excluded. This study opens the possibility of the therapeutic application of a wide spectrum host-targeted compound alone or in combination with ribavirin to combat AHF as well as other human pathogenic arenaviruses. © 2018 Wiley Periodicals, Inc.

  18. China makes an impressive breakthrough in avian influenza virus research - Discovering the "heart" of avian infl uenza virus.

    Science.gov (United States)

    Li, Y G; Wu, J F; Li, X

    2009-02-01

    The successive appearance of strains of epizootic avian influenza A virus with the subtype H5N1 in China has attracted considerable concern from the public and Chinese authorities. According to the latest WHO estimates as of February 2, 2009, the number of H5N1 virus deaths in China totaled 25, second only to Indonesia and Viet Nam (http://www.who.int/csr/disease/avian_influenza/country/cases_table_2009_02_02/en/index.html). The H5N1 virus is highly contagious among birds and is fatal when transmitted to humans, though the means by which this occurs is still unknown. Owing to the possible variation of the H5N1 prototype virus, together with the fact that it has the propensity to exchange genes with influenza viruses from other species, humans have no natural immunity to the virus. Despite years of efforts, the exact pathogenesis of H5N1 transmission to humans is still not completely clear, nor is potential human-tohuman transmission as could lead to an epidemic or even worldwide pandemic (Enserink M. Science. 2009; 323:324). Unfortunately, current antiviral treatment and therapeutic measures cannot effectively overcome this virulent virus that causes highly pathogenic avian influenza (HPAI). Researchers from around the world are working to study the virology of influenza viruses, including their methods of infiltration, replication, and transcription, to elucidate the mechanisms of unremitting viral infection in terms of aspects such as the virus, host, and environment. These researchers are also working to identify potential molecular targets related to H5N1 for anti-influenza drug intervention. A recent H5N1-related study from China provides encouraging information. According to the People's Daily (Renmin Ribao), a newspaper out of Beijing, professor Liu Yingfang, academician Rao Zihe, and fellow researchers from more than 6 research centers, including the Institute of Biophysics Chinese Academy of Sciences, Nankai University, and Tsinghua University, have

  19. Absence of Active Hepatitis C Virus Infection in Human Immunodeficiency Virus Clinics in Zambia and Mozambique.

    Science.gov (United States)

    Wandeler, Gilles; Mulenga, Lloyd; Hobbins, Michael; Joao, Candido; Sinkala, Edford; Hector, Jonas; Aly, Musa; Chi, Benjamin H; Egger, Matthias; Vinikoor, Michael J

    2016-03-01

    Few studies have evaluated the prevalence of replicating hepatitis C virus (HCV) infection in sub-Saharan Africa. Among 1812 individuals infected with human immunodeficiency virus, no patient in rural Mozambique and 4 patients in urban Zambia were positive for anti-HCV antibodies. Of these, none had confirmed HCV replication.

  20. Treatment of Oseltamivir-Resistant Influenza A (H1N1) Virus Infections in Mice With Antiviral Agents

    Science.gov (United States)

    Smee, Donald F.; Julander, Justin G.; Tarbet, E. Bart; Gross, Matthew; Nguyen, Jack

    2012-01-01

    Influenza A/Mississippi/03/2001 (H1N1) and A/Hong Kong/2369/2009 (H1N1) viruses containing the neuraminidase gene mutation H275Y (conferring resistance to oseltamivir) were adapted to mice and evaluated for suitability as models for lethal infection and antiviral treatment. The viral neuraminidases were resistant to peramivir and oseltamivir carboxylate but sensitive to zanamivir. Similar pattern of antiviral activity were seen in MDCK cell assays. Lethal infections were achieved in mice with the two viruses. Oral oseltamivir at 100 and 300 mg/kg/day bid for 5 d starting at −2 h gave 30 and 60% protection from death, respectively, due to the A/Mississippi/03/2001 infection. Intraperitoneal treatments with zanamivir at 30 and 100 mg/kg/day starting at −2 h gave 60 and 90% protection, respectively. Neither compound at ≤300 mg/kg/day protected mice when treatments began at +24 h. Amantadine was effective at 10, 30, and 100 mg/kg/day, rimantadine was protective at 10 and 30 mg/kg/day (highest dose tested), and ribavirin was active at 30 and 75 mg/kg/day, with survival ranging from 60–100% for oral treatments initiated at −2 h. For treatments begun at +24 h, amantadine was protective at 30 and 100 mg/kg/day, rimantadine showed efficacy at 10 and 30 mg/kg/day, and ribavirin was active at 75 mg/kg/day, with 60–100% survival per group. In the A/Hong Kong/2369/2009 infection, oral oseltamivir at 100 and 300 mg/kg/day starting at −2 h gave 50 and 70% protection from death, respectively. These infection models will be useful to study newly discovered anti-influenza virus agents and to evaluate compounds in combination. PMID:22809862

  1. Circulating intercellular adhesion molecule-1 (ICAM-1) as an early and sensitive marker for virus-induced T cell activation

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Johansen, J; Marker, O

    1995-01-01

    The effect of systemic virus infection on the level of circulating ICAM-1 (cICAM-1) in serum, and the role of virus-activated T cells in this context, were studied using the murine lymphocytic choriomeningitis virus infection as primary model system. A marked virus-induced elevation in cICAM-1...

  2. Anti-pandemic influenza A(H1N1) virus potential of catechin and gallic acid.

    Science.gov (United States)

    You, Huey-Ling; Huang, Chao-Chun; Chen, Chung-Jen; Chang, Cheng-Chin; Liao, Pei-Lin; Huang, Sheng-Teng

    2017-12-26

    The pandemic influenza A (H1N1) virus has spread worldwide and infected a large proportion of the human population. Discovery of new and effective drugs for the treatment of influenza is a crucial issue for the global medical community. According to our previous study, TSL-1, a fraction of the aqueous extract from the tender leaf of Toonasinensis, has demonstrated antiviral activities against pandemic influenza A (H1N1) through the down-regulation of adhesion molecules and chemokine to prevent viral attachment. The aim of the present study was to identify the active compounds in TSL-1 which exert anti-influenza A (H1N1) virus effects. XTT assay was used to detect the cell viability. Meanwhile, the inhibitory effect on the pandemic influenza A (H1N1) virus was analyzed by observing plaque formation, qRT-PCR, neuraminidase activity, and immunofluorescence staining of influenza A-specific glycoprotein. Both catechin and gallic acid were found to be potent inhibitors in terms of influenza virus mRNA replication and MDCK plaque formation. Additionally, both compounds inhibited neuraminidase activities and viral glycoprotein. The 50% effective inhibition concentration (EC 50 ) of catechin and gallic acid for the influenza A (H1N1) virus were 18.4 μg/mL and 2.6 μg/mL, respectively; whereas the 50% cytotoxic concentrations (CC 50 ) of catechin and gallic acid were >100 μg/mL and 22.1 μg/mL, respectively. Thus, the selectivity indexes (SI) of catechin and gallic acid were >5.6 and 22.1, respectively. The present study demonstrates that catechin might be a safe reagent for long-term use to prevent influenza A (H1N1) virus infection; whereas gallic acid might be a sensitive reagent to inhibit influenza virus infection. We conclude that these two phyto-chemicals in TSL-1 are responsible for exerting anti-pandemic influenza A (H1N1) virus effects. Copyright © 2017. Published by Elsevier Taiwan LLC.

  3. The metabolic activator FOXO1 binds hepatitis B virus DNA and activates its transcription

    International Nuclear Information System (INIS)

    Shlomai, Amir; Shaul, Yosef

    2009-01-01

    Hepatitis B virus (HBV) is a small DNA virus that targets the liver and infects humans worldwide. Recently we have shown that the metabolic regulator PGC-1α coactivates HBV transcription thereby rendering the virus susceptible to fluctuations in the nutritional status of the liver. PGC-1α coactivation of HBV is mediated through the liver-enriched nuclear receptor HNF4α and through another yet unknown transcription factor(s). Here we show that the forkhead transcription factor FOXO1, a known target for PGC-1α coactivation and a central mediator of glucose metabolism in the liver, binds HBV core promoter and activates its transcription. This activation is further enhanced in the presence of PGC-1α, implying that FOXO1 is a target for PGC-1α coactivation of HBV transcription. Thus, our results identify another key metabolic regulator as an activator of HBV transcription, thereby supporting the principle that HBV gene expression is regulated in a similar way to key hepatic metabolic genes.

  4. How we treat chronic active Epstein-Barr virus infection.

    Science.gov (United States)

    Sawada, Akihisa; Inoue, Masami; Kawa, Keisei

    2017-04-01

    Chronic active Epstein-Barr virus infection (CAEBV) is a prototype of the EBV-associated T- or NK-cell lymphoproliferative diseases, which also include hypersensitivity to mosquito bites and severe-type hydroavacciniforme. The manifestations of CAEBV are often self-limiting with minimum supportive care or only prednisolone and cyclosporine A with or without etoposide. However, allogeneic hematopoietic stem cell transplantation (HSCT) is the only cure, without which patients with CAEBV die within several years. A severe hypercytokinemia and hemophagocytic syndrome, which may occur suddenly, often results in a fatal clinical course. At out institute, we have established a 3-step strategy, including allogeneic HSCT, for the treatment of CAEBV. Seventy-nine patients with CAEBV and related diseases have been treated to date. The 3-year overall survival rate (3y-OS) is currently 87.3 ± 4.2% after planned allogeneic HSCT. However, 3y-OS in patients with uncontrolled active disease is only 16.7 ± 10.8%. To maximize survival rates with minimized late sequelae, we recommend earlier initiation and completion of the 3-step treatment without watchful waiting. We present six illustrative and difficult cases (including severe hypercytokinemia or emergent HSCT) and discuss them together with 73 residual cases.

  5. Interferon-mediated antiviral activities of Angelica tenuissima Nakai and its active components.

    Science.gov (United States)

    Weeratunga, Prasanna; Uddin, Md Bashir; Kim, Myun Soo; Lee, Byeong-Hoon; Kim, Tae-Hwan; Yoon, Ji-Eun; Ma, Jin Yeul; Kim, Hongik; Lee, Jong-Soo

    2016-01-01

    Angelica tenuissima Nakai is a widely used commodity in traditional medicine. Nevertheless, no study has been conducted on the antiviral and immune-modulatory properties of an aqueous extract of Angelica tenuissima Nakai. In the present study, we evaluated the antiviral activities and the mechanism of action of an aqueous extract of Angelica tenuissima Nakai both in vitro and in vivo. In vitro, an effective dose of Angelica tenuissima Nakai markedly inhibited the replication of Influenza A virus (PR8), Vesicular stomatitis virus (VSV), Herpes simplex virus (HSV), Coxsackie virus, and Enterovirus (EV-71) on epithelial (HEK293T/HeLa) and immune (RAW264.7) cells. Such inhibition can be described by the induction of the antiviral state in cells by antiviral, IFNrelated gene induction and secretion of IFNs and pro-inflammatory cytokines. In vivo, Angelica tenuissima Nakai treated BALB/c mice displayed higher survivability and lower lung viral titers when challenged with lethal doses of highly pathogenic influenza A subtypes (H1N1, H5N2, H7N3, and H9N2). We also found that Angelica tenuissima Nakai can induce the secretion of IL-6, IFN-λ, and local IgA in bronchoalveolar lavage fluid (BALF) of Angelica tenuissima Nakai treated mice, which correlating with the observed prophylactic effects. In HPLC analysis, we found the presence of several compounds in the aqueous fraction and among them; we evaluated antiviral properties of ferulic acid. Therefore, an extract of Angelica tenuissima Nakai and its components, including ferulic acid, play roles as immunomodulators and may be potential candidates for novel anti-viral/anti-influenza agents.

  6. Antiviral activity of gliotoxin, gentian violet and brilliant green against Nipah and Hendra virus in vitro

    Directory of Open Access Journals (Sweden)

    Meyer Adam G

    2009-11-01

    Full Text Available Abstract Background Using a recently described monolayer assay amenable to high throughput screening format for the identification of potential Nipah virus and Hendra virus antivirals, we have partially screened a low molecular weight compound library (>8,000 compounds directly against live virus infection and identified twenty eight promising lead molecules. Initial single blind screens were conducted with 10 μM compound in triplicate with a minimum efficacy of 90% required for lead selection. Lead compounds were then further characterised to determine the median efficacy (IC50, cytotoxicity (CC50 and the in vitro therapeutic index in live virus and pseudotype assay formats. Results While a number of leads were identified, the current work describes three commercially available compounds: brilliant green, gentian violet and gliotoxin, identified as having potent antiviral activity against Nipah and Hendra virus. Similar efficacy was observed against pseudotyped Nipah and Hendra virus, vesicular stomatitis virus and human parainfluenza virus type 3 while only gliotoxin inhibited an influenza A virus suggesting a non-specific, broad spectrum activity for this compound. Conclusion All three of these compounds have been used previously for various aspects of anti-bacterial and anti-fungal therapy and the current results suggest that while unsuitable for internal administration, they may be amenable to topical antiviral applications, or as disinfectants and provide excellent positive controls for future studies.

  7. Detection of enteric viruses in activated sludge by feasible concentration methods.

    Science.gov (United States)

    Prado, Tatiana; Gaspar, Ana Maria Coimbra; Miagostovich, Marize Pereira

    2014-01-01

    Human enteric viruses are responsible to cause several diseases, including gastroenteritis and hepatitis, and can be present in high amounts in sewage sludge. This study compared virus recovery efficiency of two feasible concentration methods used for detecting human adenovirus (HAdV), rotavirus species A (RV-A), norovirus genogroup II (NoV GII) and hepatitis A virus (HAV) in sewage sludge from an activated sludge process. Twelve sewage sludge samples were collected bi-monthly from January to July, 2011. Ultracentrifugation was compared with a simplified protocol based on beef extract elution for recovering enteric viruses. Viruses were quantified by quantitative real-time PCR assays and virus recovery efficiency and limits of detection were determined. Methods showed mean recovery rates lower than 7.5%, presenting critical limits of detection (higher than 10(2) - 10(3) genome copies - GC L(-1) for all viruses analyzed). Nevertheless, HAdV were detected in 90% of the analyzed sewage sludge samples (range: 1.8 × 10(4) to 1.1 × 10(5) GC L(-1)), followed by RV-A and NoV (both in 50%) and HAV (8%). Results suggesting that activated sludge is contaminated with high viral loads and HAdV are widely disseminated in these samples. The low virus recovery rates achieved, especially for HAV, indicate that other feasible concentration methods could be developed to improve virus recovery efficiency in these environmental matrices.

  8. Matrix Metalloproteinase 9 Exerts Antiviral Activity against Respiratory Syncytial Virus.

    Directory of Open Access Journals (Sweden)

    Abdoulaye J Dabo

    Full Text Available Increased lung levels of matrix metalloproteinase 9 (MMP9 are frequently observed during respiratory syncytial virus (RSV infection and elevated MMP9 concentrations are associated with severe disease. However little is known of the functional role of MMP9 during lung infection with RSV. To determine whether MMP9 exerted direct antiviral potential, active MMP9 was incubated with RSV, which showed that MMP9 directly prevented RSV infectivity to airway epithelial cells. Using knockout mice the effect of the loss of Mmp9 expression was examined during RSV infection to demonstrate MMP9's role in viral clearance and disease progression. Seven days following RSV infection, Mmp9-/- mice displayed substantial weight loss, increased RSV-induced airway hyperresponsiveness (AHR and reduced clearance of RSV from the lungs compared to wild type mice. Although total bronchoalveolar lavage fluid (BALF cell counts were similar in both groups, neutrophil recruitment to the lungs during RSV infection was significantly reduced in Mmp9-/- mice. Reduced neutrophil recruitment coincided with diminished RANTES, IL-1β, SCF, G-CSF expression and p38 phosphorylation. Induction of p38 signaling was required for RANTES and G-CSF expression during RSV infection in airway epithelial cells. Therefore, MMP9 in RSV lung infection significantly enhances neutrophil recruitment, cytokine production and viral clearance while reducing AHR.

  9. Antiviral Activity of Porcine Interferon Regulatory Factor 1 against Swine Viruses in Cell Culture.

    Science.gov (United States)

    Li, Yongtao; Chang, Hongtao; Yang, Xia; Zhao, Yongxiang; Chen, Lu; Wang, Xinwei; Liu, Hongying; Wang, Chuanqing; Zhao, Jun

    2015-11-17

    Interferon regulatory factor 1 (IRF1), as an important transcription factor, is abundantly induced upon virus infections and participates in host antiviral immune responses. However, the roles of porcine IRF1 (poIRF1) in host antiviral defense remain poorly understood. In this study, we determined that poIRF1 was upregulated upon infection with viruses and distributed in nucleus in porcine PK-15 cells. Subsequently, we tested the antiviral activities of poIRF1 against several swine viruses in cells. Overexpression of poIRF1 can efficiently suppress the replication of viruses, and knockdown of poIRF1 promotes moderately viral replication. Interestingly, overexpression of poIRF1 enhances dsRNA-induced IFN-β and IFN-stimulated response element (ISRE) promoter activation, whereas knockdown of poIRF1 cannot significantly affect the activation of IFN-β promoter induced by RNA viruses. This study suggests that poIRF1 plays a significant role in cellular antiviral response against swine viruses, but might be dispensable for IFN-β induction triggered by RNA viruses in PK-15 cells. Given these results, poIRF1 plays potential roles in cellular antiviral responses against swine viruses.

  10. Hepatitis C virus translation preferentially depends on active RNA replication.

    Directory of Open Access Journals (Sweden)

    Helene Minyi Liu

    Full Text Available Hepatitis C virus (HCV RNA initiates its replication on a detergent-resistant membrane structure derived from the endoplasmic reticulum (ER in the HCV replicon cells. By performing a pulse-chase study of BrU-labeled HCV RNA, we found that the newly-synthesized HCV RNA traveled along the anterograde-membrane traffic and moved away from the ER. Presumably, the RNA moved to the site of translation or virion assembly in the later steps of viral life cycle. In this study, we further addressed how HCV RNA translation was regulated by HCV RNA trafficking. When the movement of HCV RNA from the site of RNA synthesis to the Golgi complex was blocked by nocodazole, an inhibitor of ER-Golgi transport, HCV protein translation was surprisingly enhanced, suggesting that the translation of viral proteins occurred near the site of RNA synthesis. We also found that the translation of HCV proteins was dependent on active RNA synthesis: inhibition of viral RNA synthesis by an NS5B inhibitor resulted in decreased HCV viral protein synthesis even when the total amount of intracellular HCV RNA remained unchanged. Furthermore, the translation activity of the replication-defective HCV replicons or viral RNA with an NS5B mutation was greatly reduced as compared to that of the corresponding wildtype RNA. By performing live cell labeling of newly synthesized HCV RNA and proteins, we further showed that the newly synthesized HCV proteins colocalized with the newly synthesized viral RNA, suggesting that HCV RNA replication and protein translation take place at or near the same site. Our findings together indicate that the translation of HCV RNA is coupled to RNA replication and that the both processes may occur at the same subcellular membrane compartments, which we term the replicasome.

  11. Erythrocyte-mediated delivery of a new homodinucleotide active against human immunodeficiency virus and herpes simplex virus.

    Science.gov (United States)

    Rossi, L; Serafini, S; Cappellacci, L; Balestra, E; Brandi, G; Schiavano, G F; Franchetti, P; Grifantini, M; Perno, C F; Magnani, M

    2001-06-01

    Monocyte-derived macrophages (MDMs) play a central role in the pathogenesis of infection by human immunodeficiency virus (HIV-1) and represent one of the main reservoirs of the virus in the body. In addition, MDMs can easily be infected by various herpes viruses, including herpes simplex virus type 1 (HSV-1). We have synthesized a new antiviral agent (Bis-PMEA) that consists of two 9-(2-phosphonylmethoxyethyl)adenine (PMEA) molecules bound by a phosphate bridge. This nucleotide analogue, like the parent compound PMEA, has strong and selective activity against HIV-1 and HSV-1. A drug-targeting system previously developed in our laboratory was used for the selective delivery of these drugs to macrophages. Bis-PMEA and PMEA were encapsulated into autologous erythrocytes by a procedure of hypotonic dialysis and isotonic resealing. Loaded erythrocytes were modified to increase their recognition and phagocytosis by human macrophages. By administering Bis-PMEA-loaded erythrocytes to macrophages, 47% of Bis-PMEA and 28% of PMEA was still present 10 days after phagocytosis; in contrast, only 12% of PMEA was found in macrophages receiving PMEA-loaded erythrocytes. Bis-PMEA-loaded erythrocytes were then added to macrophages infected with HIV-1 and HSV-1 and their antiviral activity evaluated. Remarkable protection was obtained against HIV-1 and HSV-1 infection (95 and 85%, respectively). Therefore, Bis-PMEA acts as an efficient antiviral prodrug that, following selective targeting to macrophages by means of loaded erythrocytes, can protect a refractory cell compartment.

  12. Antiviral activity of plant extract from Tanacetum vulgare against Cucumber Mosaic Virus and Potato Virus Y

    Directory of Open Access Journals (Sweden)

    Nikolay Petrov

    2016-09-01

    Full Text Available Cucumber mosaic virus (CMV and Potato virus Y (PVY have been described among the top five important viruses infecting vegetable species worldwide. They cause severe damages in fruits and cultivated plants. There is currently no available effective pesticide to control these viral diseases. Higher plants contain a wide spectrum of secondary metabolites such as phenolics, flavonoids, quinones, tannins, essential oils, alkaloids, saponins, sterols and others. Extracts prepared from different plants have been reported to have a variety of properties including antifungal, antiviral and antibacterial properties against pathogens. Tanacetum vulgare (Tansy is native to Europe, Asia, and North Africa. It has many horticultural and pharmacological qualities. T. vulgare is principally used in traditional Asian and North African medicine as an antihelminthic, antispasmodic, stimulant to abdominal viscera, tonic, antidiabetic and diuretic, and it is antihypertensive. In our research we established antiviral effect of methanol extract from T. vulgare against CMV and PVY in tomato plants.

  13. A novel, polymer-coated oncolytic measles virus overcomes immune suppression and induces robust antitumor activity

    Directory of Open Access Journals (Sweden)

    Kaname Nosaki

    2016-01-01

    Full Text Available Although various therapies are available to treat cancers, including surgery, chemotherapy, and radiotherapy, cancer has been the leading cause of death in Japan for the last 30 years, and new therapeutic modalities are urgently needed. As a new modality, there has recently been great interest in oncolytic virotherapy, with measles virus being a candidate virus expected to show strong antitumor effects. The efficacy of virotherapy, however, was strongly limited by the host immune response in previous clinical trials. To enhance and prolong the antitumor activity of virotherapy, we combined the use of two newly developed tools: the genetically engineered measles virus (MV-NPL and the multilayer virus-coating method of layer-by-layer deposition of ionic polymers. We compared the oncolytic effects of this polymer-coated MV-NPL with the naked MV-NPL, both in vitro and in vivo. In the presence of anti-MV neutralizing antibodies, the polymer-coated virus showed more enhanced oncolytic activity than did the naked MV-NPL in vitro. We also examined antitumor activities in virus-treated mice. Complement-dependent cytotoxicity and antitumor activities were higher in mice treated with polymer-coated MV-NPL than in mice treated with the naked virus. This novel, polymer-coated MV-NPL is promising for clinical cancer therapy in the future.

  14. Controlled immobilisation of active enzymes on the cowpea mosaic virus capsid

    Science.gov (United States)

    Aljabali, Alaa A. A.; Barclay, J. Elaine; Steinmetz, Nicole F.; Lomonossoff, George P.; Evans, David J.

    2012-08-01

    Immobilisation of horseradish peroxidase (HRP) and glucose oxidase (GOX) via covalent attachment of modified enzyme carbohydrate to the exterior of the cowpea mosaic virus (CPMV) capsid gave high retention of enzymatic activity. The number of enzymes bound per virus was determined to be about eleven for HRP and 2-3 for GOX. This illustrates that relatively large biomacromolecules can be readily coupled to the virus surface using simple conjugation strategies. Virus-biomacromolecule hybrids have great potential for uses in catalysis, diagnostic assays or biosensors.Immobilisation of horseradish peroxidase (HRP) and glucose oxidase (GOX) via covalent attachment of modified enzyme carbohydrate to the exterior of the cowpea mosaic virus (CPMV) capsid gave high retention of enzymatic activity. The number of enzymes bound per virus was determined to be about eleven for HRP and 2-3 for GOX. This illustrates that relatively large biomacromolecules can be readily coupled to the virus surface using simple conjugation strategies. Virus-biomacromolecule hybrids have great potential for uses in catalysis, diagnostic assays or biosensors. Electronic supplementary information (ESI) available: Alternative conjugation strategies, agarose gel electrophoresis of CPMV and CPMV-HRP conjugates, UV-vis spectrum of HRP-ADHCPMV, agarose gel electrophoresis of GOX-ADHCPMV particles and corresponding TEM image, calibration curves for HRP-ADHCPMV and GOX-ADHCPMV, DLS data for GOX-ADHCPMV are made available. See DOI: 10.1039/c2nr31485a

  15. Highly sensitive detection of influenza virus in saliva by real-time PCR method using sugar chain-immobilized gold nanoparticles; application to clinical studies

    Directory of Open Access Journals (Sweden)

    Yasuo Suda

    2015-09-01

    Full Text Available A highly sensitive and convenient method for detecting influenza virus was developed using modified end-point melt curve analysis of a RT-qPCR SYBR Green method and influenza virus-binding sugar chain-immobilized gold-nanoparticles (SGNP. Because SGNPs capture influenza viruses, the virus-SGNP complex was separated easily by centrifugation. Viral RNA was detected at very low concentrations, suggesting that SGNP increased sensitivity compared with standard methods. This method was applied to clinical studies. Influenza viruses were detected in saliva of patients or inpatients who had been considered influenza-free by a rapid diagnostic assay of nasal swabs. Furthermore, the method was applied to a human trial of prophylactic anti-influenza properties of yogurt containing Lactobacillus acidophilus L-92. The incidence of influenza viruses in saliva of the L-92 group was found to be significantly lower compared to the control group. Thus, this method was useful for monitoring the course of anti-influenza treatment or preventive measures against nosocomial infection.

  16. 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

    -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......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...... had a more modest antiviral activity. Finally, pretreatment with IFN-lambda enhanced the levels of IFN-gamma in serum after HSV-2 infection. Thus, type III IFNs are expressed in response to most viruses and display potent antiviral activity in vivo against select viruses. The discrepancy between...

  17. 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

    -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......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...... had a more modest antiviral activity. Finally, pretreatment with IFN-lambda enhanced the levels of IFN-gamma in serum after HSV-2 infection. Thus, type III IFNs are expressed in response to most viruses and display potent antiviral activity in vivo against select viruses. The discrepancy between...

  18. Development of a broad-spectrum antiviral with activity against Ebola virus.

    Science.gov (United States)

    Aman, M Javad; Kinch, Michael S; Warfield, Kelly; Warren, Travis; Yunus, Abdul; Enterlein, Sven; Stavale, Eric; Wang, Peifang; Chang, Shaojing; Tang, Qingsong; Porter, Kevin; Goldblatt, Michael; Bavari, Sina

    2009-09-01

    We report herein the identification of a small molecule therapeutic, FGI-106, which displays potent and broad-spectrum inhibition of lethal viral hemorrhagic fevers pathogens, including Ebola, Rift Valley and Dengue Fever viruses, in cell-based assays. Using mouse models of Ebola virus, we further demonstrate that FGI-106 can protect animals from an otherwise lethal infection when used either in a prophylactic or therapeutic setting. A single treatment, administered 1 day after infection, is sufficient to protect animals from lethal Ebola virus challenge. Cell-based assays also identified inhibitory activity against divergent virus families, which supports a hypothesis that FGI-106 interferes with a common pathway utilized by different viruses. These findings suggest FGI-106 may provide an opportunity for targeting viral diseases.

  19. Development of a model describing virus removal process in an activated sludge basin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T.; Shiragami, N. Unno, H. [Tokyo Institute of Technology, Tokyo (Japan)

    1995-06-20

    The virus removal process from the liquid phase in an activated sludge basin possibly consists of physicochemical processes, such as adsorption onto sludge flocs, biological processes such as microbial predating and inactivation by virucidal components excreted by microbes. To describe properly the virus behavior in an activated sludge basin, a simple model is proposed based on the experimental data obtained using a poliovirus type 1. A three-compartments model, which include the virus in the liquid phase and in the peripheral and inner regions of sludge flocs is employed. By using the model, the Virus removal process was successfully simulated to highlight the implication of its distribution in the activated sludge basin. 17 refs., 8 figs.

  20. Antiviral Activity of Novel Quinoline Derivatives against Dengue Virus Serotype 2

    Directory of Open Access Journals (Sweden)

    Carolina de la Guardia

    2018-03-01

    Full Text Available Dengue virus causes dengue fever, a debilitating disease with an increasing incidence in many tropical and subtropical territories. So far, there are no effective antivirals licensed to treat this virus. Here we describe the synthesis and antiviral activity evaluation of two compounds based on the quinoline scaffold, which has shown potential for the development of molecules with various biological activities. Two of the tested compounds showed dose-dependent inhibition of dengue virus serotype 2 in the low and sub micromolar range. The compounds 1 and 2 were also able to impair the accumulation of the viral envelope glycoprotein in infected cells, while showing no sign of direct virucidal activity and acting possibly through a mechanism involving the early stages of the infection. The results are congruent with previously reported data showing the potential of quinoline derivatives as a promising scaffold for the development of new antivirals against this important virus.

  1. Antiviral Activity of Graphene–Silver Nanocomposites against Non-Enveloped and Enveloped Viruses

    Directory of Open Access Journals (Sweden)

    Yi-Ning Chen

    2016-04-01

    Full Text Available The discovery of novel antiviral materials is important because many infectious diseases are caused by viruses. Silver nanoparticles have demonstrated strong antiviral activity, and graphene is a potential antimicrobial material due to its large surface area, high carrier mobility, and biocompatibility. No studies on the antiviral activity of nanomaterials on non-enveloped viruses have been reported. To investigate the antiviral activity of graphene oxide (GO sheets and GO sheets with silver particles (GO-Ag against enveloped and non-enveloped viruses, feline coronavirus (FCoV with an envelope and infectious bursal disease virus (IBDV without an envelope were chosen. The morphology and sizes of GO and GO-Ag were characterized by transmission, scanning electron microscopy, and X-ray diffraction. A virus inhibition assay was used to identify the antiviral activity of GO and GO-Ag. Go-Ag inhibited 25% of infection by FCoV and 23% by IBDV, whereas GO only inhibited 16% of infection by FCoV but showed no antiviral activity against the infection by IBDV. Further application of GO and GO-Ag can be considered for personal protection equipment to decrease the transmission of viruses.

  2. Virucidal activity of Colombian Lippia essential oils on dengue virus replication in vitro

    Directory of Open Access Journals (Sweden)

    Raquel Elvira Ocazionez

    2010-05-01

    Full Text Available The inhibitory effect of Lippia alba and Lippia citriodora essential oils on dengue virus serotypes replication in vitro was investigated. The cytotoxicity (CC50 was evaluated by the MTT assay and the mode of viral inhibitory effect was investigated with a plaque reduction assay. The virus was treated with the essential oil for 2 h at 37ºC before cell adsorption and experiments were conducted to evaluate inhibition of untreated-virus replication in the presence of oil. Antiviral activity was defined as the concentration of essential oil that caused 50% reduction of the virus plaque number (IC50. L. alba oil resulted in less cytotoxicity than L. citriodora oil (CC50: 139.5 vs. 57.6 μg/mL. Virus plaque reduction for all four dengue serotypes was observed by treatment of the virus before adsorption on cell. The IC50 values for L. alba oil were between 0.4-32.6 μg/mL and between 1.9-33.7 μg/mL for L. citriodora oil. No viral inhibitory effect was observed by addition of the essential oil after virus adsorption. The inhibitory effect of the essential oil seems to cause direct virus inactivation before adsorption on host cell.

  3. ACTIVE IMMUNICATION OF GUINEA PIGS WITH THE VIRUS OF EQUINE ENCEPHALOMYELITIS

    Science.gov (United States)

    Olitsky, Peter K.; Cox, Herald R.

    1936-01-01

    Active Eastern or Western equine encephalomyelitis virus in three forms,—chemically untreated but simply passaged through series of mice; adsorbed on alumina Gel C, and precipitated by tannin,—yielded practically the same results when employed for the immunization of guinea pigs. The virus is not inactivated by the process of adsorption or precipitation : guinea pigs and mice inoculated in the brain with these materials develop lethal encephalomyelitis in the same manner as when chemically untreated mouse passage virus has been used. Moreover, there is no difference in the rate of absorption in vivoof the chemically treated and untreated virus preparations. After storage of the three immunizing preparations—the longest periods thus far studied being 2 to 3 months for mouse passage and for precipitated suspensions, and 6 months for adsorbed material—each was found to contain an amount of virus sufficient to produce immunity in animals against the usual intracerebral test inoculation. Finally, the protection afforded by the three preparations is apparently durable, as is true of many active viruses utilized in preventive treatments. The amount of the virus necessary to confer protection may be defined as that which immunizes (a) with the least number of antigenic units and (b) with the minimum of febrile reaction and blood infection. In proportion as this amount is exceeded, the incidence of fever and of circulating virus increases and, on the other hand, as this amount is decreased, the degree of induced immunity is diminished. We have thus shown that for this particular virus and in the guinea pig, one or two subcutaneous doses of I cc. of any of the different virus preparations, each containing 3 x 103 to 3 x 104 mouse infective units, bring about protection regularly against experimental infection by way of the nose or subcutis. The results are irregular when the test is made by way of the brain. By three injections, resistance is invariably obtained

  4. Activation of the blood-brain barrier by SIV (simian immunodeficiency virus) requires cell-associated virus and is not restricted to endothelial cell activation.

    Science.gov (United States)

    MacLean, A G; Rasmussen, T A; Bieniemy, D; Lackner, A A

    2004-11-01

    The primary cell infected during acute HIV neuropathogenesis is the monocyte-derived macrophage. We have demonstrated that there is activation of the BBB (blood-brain barrier) during acute viral infection and at terminal AIDS. However, it has never been determined if there is a requirement for the virus to be carried through the BBB or how these Trojan horses would be induced to cross the BBB. We added SIVmac251-infected (SIV is simian immunodeficiency virus) mononuclear cells (and their supernatants) to the luminal or abluminal compartment of our BBB model. There was activation of both sides of the BBB model, only if viral-infected cells were added to the luminal compartment, as opposed to the addition of cell-free supernatants. This suggests that cell-associated virus is essential for the activation of the BBB. This, in turn, would be expected to lead to further infiltration of cells capable of viral infection. VCAM-1 (vascular cell adhesion molecule 1) staining revealed, for the first time, that there is an absolute requirement for virally infected cells, and not just the presence of virus for the activation of the BBB.

  5. A mini-review of anti-hepatitis B virus activity of medicinal plants

    Directory of Open Access Journals (Sweden)

    Manzer H. Siddiqui

    2017-01-01

    Full Text Available Medicinal plants are of undoubted value, as they have been used for centuries to treat various diseases and health disorders in almost every part of the world. In several studies, the use of medicinal plants was found effective in treatment of infectious and non-infectious diseases. The World Health Organization has been working for many years to identify all surviving medicinal plants on the earth. An important step has also been taken by the Natural Health Product Regulation of Canada for promotion and usages of natural products. At present, the rapidly growing population of the world is facing many challenges from various infectious diseases that are associated with hepatitis A, B and C virus, human immunodeficiency virus, influenza virus, dengue virus and new emerging viruses. Hepatitis B virus causes a severe and frequently transmittable disease of the liver. Millions of people worldwide suffer from hepatitis B virus (HBV infection. The drugs available on the market for the treatment of hepatitis B are not sufficient and also cause side effects in patients suffering from HBV infection. The pharmaceutical companies are searching for suitable alternative and natural inhibitors of HBV. Therefore, it is important to explore and use plants as a source of new medicines to treat this infectious disease, because single plants contain a priceless pool of active ingredients which could help in the production of pharmaceutical-grade peptides or proteins. However, the knowledge of the antiviral activity of medicinal plants is still limited.

  6. Serological evidence of hepatitis e virus activity among slaughtered ...

    African Journals Online (AJOL)

    Hepatitis E (HE) is endemic and of public health importance in many developing countries where poor sanitation condition has been identified as its major predisposing factor. In Europe and America, direct contact with pigs is linked with the presence of HE virus (HEV) in humans. However, despite poor sanitary conditions ...

  7. Chemical composition of Propolis Extract ACF® and activity against herpes simplex virus.

    Science.gov (United States)

    Bankova, V; Galabov, A S; Antonova, D; Vilhelmova, N; Di Perri, B

    2014-09-25

    Propolis Extract ACF(®) (PPE) is a purified extract manufactured from propolis collected in a Canadian region rich in poplar trees, and it is the active substance of a topical ointment used against herpes labialis (cold sores or fever blisters). Aim of this study was to analyze the chemical composition of PPE in order to understand the plant origin and possible relations between compounds and antiviral activity, and to characterize the antiviral activity of the extract against herpes simplex virus in vitro. The analysis of the propolis extract samples was conducted by Gas Chromatography-Mass Spectrometry (GC-MS). The antiviral activity was tested against herpes simplex viruses type 1 and type 2 in MDBK cell cultures by treating the cells with PPE at the time of virus adsorption, and by incubating the virus with the extract before infection (virucidal assay). Results from the GC-MS analyses revealed a dual plant origin of PPE, with components derived from resins of two different species of poplar. The chemical composition appeared standardized between extract samples and was also reproduced in the sample of topical ointment. The antiviral studies showed that PPE had a pronounced virucidal effect against herpes simplex viruses type 1 and type 2, and also interfered with virus adsorption. Copyright © 2014 Elsevier GmbH. All rights reserved.

  8. Biochemical activities of T-antigen proteins encoded by simian virus 40 A gene deletion mutants.

    OpenAIRE

    Clark, R; Peden, K; Pipas, J M; Nathans, D; Tjian, R

    1983-01-01

    We have analyzed T antigens produced by a set of simian virus 40 (SV40) A gene deletion mutants for ATPase activity and for binding to the SV40 origin of DNA replication. Virus stocks of nonviable SV40 A gene deletion mutants were established in SV40-transformed monkey COS cells. Mutant T antigens were produced in mutant virus-infected CV1 cells. The structures of the mutant T antigens were characterized by immunoprecipitation with monoclonal antibodies directed against distinct regions of th...

  9. Mycoplasmal deoxyribonuclease activity in virus-infected L-cell cultures.

    Science.gov (United States)

    Stock, D A; Gentry, G A

    1969-03-01

    Cell-free extracts of Mycoplasma hominis and medium from 72-hr broth cultures had deoxyribonuclease activity like that of deoxyribonuclease I. Mg(++) stimulated activity, and the pH optimum was between 8.0 and 9.0. Double-stranded or heatdenatured deoxyribonucleic acid (DNA) served as a substrate, and oligonucleotides were produced. Cell-free extracts of L cells infected with M. hominis or M. hominis plus equine abortion virus (equine herpes virus, EAV) had greatly increased activity over that of extracts of L cells or of L cells infected with EAV alone. In the absence of M. hominis, however, extracts had little activity, most of which was in virus-infected cell cultures. Activity was found in the culture medium only in those systems in which M. hominis was present. It is concluded that M. hominis can contribute significant deoxyribonuclease activity to virus-infected as well as virusfree cell cultures. Perhaps the most interesting question arising concerns the ability of EAV, a DNA virus, to replicate successfully despite the presence of deoxyribonuclease activity at the site of replication (the nucleus).

  10. Integration of antibody by surface functionalization of graphite-encapsulated magnetic beads using ammonia gas plasma technology for capturing influenza A virus.

    Science.gov (United States)

    Sakudo, Akikazu; Chou, Han; Ikuta, Kazuyoshi; Nagatsu, Masaaki

    2015-05-01

    Antibody-integrated magnetic beads have been functionalized for influenza A virus capture. First, ammonia plasma produced by a radio frequency power source was reacted with the surface of graphite-encapsulated magnetic beads to introduce amino groups. Anti-influenza A virus hemagglutinin antibody was then anchored by its surface sulfide groups to the amino groups on the beads via N-succinimidyl 3-(2-pyridyldithio) propionate. After incubation with influenza A virus, adsorption of the virus to the beads was confirmed by immunochromatography, polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and inoculation of chicken embryonated eggs, indicating that virus infectivity is maintained and that the proposed method is useful for the enhanced detection and isolation of influenza A virus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Preparation and characterization of high-specific activity radiolabeled 50 S measles virus RNA

    International Nuclear Information System (INIS)

    Spruance, S.L.; Ashton, B.N.; Smith, C.B.

    1980-01-01

    A method is described to radiolabeled measles virus RNA for hybridization studies. Tritiated nucleosides were added to the media of measles virus infected Vero cells and negative-strand (genome) RNA with a specific activity of 6X10 5 c.p.m./μg was purified from viral nucleocapsids. 50 S RNA was the sole RNA present in nucleocapsids and self-annealed to 50% due to the presence of 25% 50 S plus-strands (anti-genomes). (Auth.)

  12. Concentration of enteric virus indicator from seawater using granular activated carbon.

    Science.gov (United States)

    Cormier, Jiemin; Gutierrez, Miguel; Goodridge, Lawrence; Janes, Marlene

    2014-02-01

    Fecal contamination of shellfish growing seawater with enteric viruses is often associated with human outbreaks of gastroenteritis. Male specific bacteriophage MS2 is correlated with those of enteric viruses in a wide range of water environments and has been used widely as a surrogate for pathogenic waterborne viruses. Since viruses in contaminated water are usually at low levels, the development of methods to concentrate viruses from water is crucial for detection purposes. In the present study, granular activated carbon was evaluated for concentration of MS2 from artificial seawater, and different parameters of the seawater were also compared. Recovery of MS2 from warm seawater (37°C) was found to be significantly greater than from cold seawater (4 and 20°C), and even greater than from fresh water (4, 20 and 37°C); the difference between seawater and fresh water became less profound when the temperatures of both were below 37°C. Although not of statistical significance, recovery of MS2 from low salinity seawater (10 and 20 parts per thousand, ppt) was greater than from high salinity seawater (30 and 40ppt). One gram of granular activated carbon was able to extract 6-log plaque forming units (PFU) of MS2 from 500ml seawater at 37°C. This study demonstrated that granular activated carbon can concentrate an enteric virus indicator from shellfish growing seawater effectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Cloning the Horse RNA Polymerase I Promoter and Its Application to Studying Influenza Virus Polymerase Activity

    Directory of Open Access Journals (Sweden)

    Gang Lu

    2016-05-01

    Full Text Available An influenza virus polymerase reconstitution assay based on the human, dog, or chicken RNA polymerase I (PolI promoter has been developed and widely used to study the polymerase activity of the influenza virus in corresponding cell types. Although it is an important member of the influenza virus family and has been known for sixty years, no studies have been performed to clone the horse PolI promoter or to study the polymerase activity of equine influenza virus (EIV in horse cells. In our study, the horse RNA PolI promoter was cloned from fetal equine lung cells. Using the luciferase assay, it was found that a 500 bp horse RNA PolI promoter sequence was required for efficient transcription. Then, using the developed polymerase reconstitution assay based on the horse RNA PolI promoter, the polymerase activity of two EIV strains was compared, and equine myxovirus resistance A protein was identified as having the inhibiting EIV polymerase activity function in horse cells. Our study enriches our knowledge of the RNA PolI promoter of eukaryotic species and provides a useful tool for the study of influenza virus polymerase activity in horse cells.

  14. Human antibodies to the dengue virus E-dimer epitope have therapeutic activity against Zika virus infection.

    Science.gov (United States)

    Fernandez, Estefania; Dejnirattisai, Wanwisa; Cao, Bin; Scheaffer, Suzanne M; Supasa, Piyada; Wongwiwat, Wiyada; Esakky, Prabagaran; Drury, Andrea; Mongkolsapaya, Juthathip; Moley, Kelle H; Mysorekar, Indira U; Screaton, Gavin R; Diamond, Michael S

    2017-11-01

    The Zika virus (ZIKV) epidemic has resulted in congenital abnormalities in fetuses and neonates. Although some cross-reactive dengue virus (DENV)-specific antibodies can enhance ZIKV infection in mice, those recognizing the DENV E-dimer epitope (EDE) can neutralize ZIKV infection in cell culture. We evaluated the therapeutic activity of human monoclonal antibodies to DENV EDE for their ability to control ZIKV infection in the brains, testes, placentas, and fetuses of mice. A single dose of the EDE1-B10 antibody given 3 d after ZIKV infection protected against lethality, reduced ZIKV levels in brains and testes, and preserved sperm counts. In pregnant mice, wild-type or engineered LALA variants of EDE1-B10, which cannot engage Fcg receptors, diminished ZIKV burden in maternal and fetal tissues, and protected against fetal demise. Because neutralizing antibodies to EDE have therapeutic potential against ZIKV, in addition to their established inhibitory effects against DENV, it may be possible to develop therapies that control disease caused by both viruses.

  15. The Dual Role of Exosomes in Hepatitis A and C Virus Transmission and Viral Immune Activation.

    Science.gov (United States)

    Longatti, Andrea

    2015-12-17

    Exosomes are small nanovesicles of about 100 nm in diameter that act as intercellular messengers because they can shuttle RNA, proteins and lipids between different cells. Many studies have found that exosomes also play various roles in viral pathogenesis. Hepatitis A virus (HAV; a picornavirus) and Hepatitis C virus (HCV; a flavivirus) two single strand plus-sense RNA viruses, in particular, have been found to use exosomes for viral transmission thus evading antibody-mediated immune responses. Paradoxically, both viral exosomes can also be detected by plasmacytoid dendritic cells (pDCs) leading to innate immune activation and type I interferon production. This article will review recent findings regarding these two viruses and outline how exosomes are involved in their transmission and immune sensing.

  16. Antiviral activity of formyl peptide receptor 2 antagonists against influenza viruses.

    Science.gov (United States)

    Courtin, Noémie; Fotso, Aurélien Fotso; Fautrad, Pierre; Mas, Floriane; Alessi, Marie-Christine; Riteau, Béatrice

    2017-07-01

    Influenza viruses are one of the most important respiratory pathogens worldwide, causing both epidemic and pandemic infections. The aim of the study was to evaluate the effect of FPR2 antagonists PBP10 and BOC2 on influenza virus replication. We determined that these molecules exhibit antiviral effects against influenza A (H1N1, H3N2, H6N2) and B viruses. FPR2 antagonists used in combination with oseltamivir showed additive antiviral effects. Mechanistically, the antiviral effect of PBP10 and BOC2 is mediated through early inhibition of virus-induced ERK activation. Finally, our preclinical studies showed that FPR2 antagonists protected mice from lethal infections induced by influenza, both in a prophylactic and therapeutic manner. Thus, FPR2 antagonists might be explored for novel treatments against influenza. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The Dual Role of Exosomes in Hepatitis A and C Virus Transmission and Viral Immune Activation

    Directory of Open Access Journals (Sweden)

    Andrea Longatti

    2015-12-01

    Full Text Available Exosomes are small nanovesicles of about 100 nm in diameter that act as intercellular messengers because they can shuttle RNA, proteins and lipids between different cells. Many studies have found that exosomes also play various roles in viral pathogenesis. Hepatitis A virus (HAV; a picornavirus and Hepatitis C virus (HCV; a flavivirus two single strand plus-sense RNA viruses, in particular, have been found to use exosomes for viral transmission thus evading antibody-mediated immune responses. Paradoxically, both viral exosomes can also be detected by plasmacytoid dendritic cells (pDCs leading to innate immune activation and type I interferon production. This article will review recent findings regarding these two viruses and outline how exosomes are involved in their transmission and immune sensing.

  18. ACTIVE IMMUNIZATION OF GUINEA PIGS WITH THE VIRUS OF EQUINE ENCEPHALOMYELITIS

    Science.gov (United States)

    Cox, Herald R.; Olitsky, Peter K.

    1936-01-01

    A study was undertaken on the effect in vivo, in the guinea pig, of equine encephalomyelitis virus antiserum upon the antigenic response to active, as compared with that to formolized, inactive virus. It was found that when animals were given subcutaneously a proper amount of hyperimmune serum 1 hour before inoculation, in the subcutis, of either active or of inactive virus, no immunity was induced against an intracerebral test of more than 1,000 and less than 10,000 M.L.D. of virus. This preventive power of the serum was lost by its dilution, the loss being proportional to the dilution, and, on the other hand, more serum was needed to obtain the blocking effect as the quantity of virus was increased. When an insufficient amount of serum was introduced into the animals along with the same quantities of active virus or formolized vaccine, a certain number of those receiving the untreated virus succumbed to virus infection in the course of the inoculations, but the survivors were rendered resistant to the intracerebral test; all the guinea pigs treated with higher dilutions of serum and with formolized material were brought safely to an immune state. The point to be stressed then is that antigenic stimuli present in untreated active virus and in formolized virus tissue suspensions in which no active virus is demonstrable by drastic tests (1) and which are wholly noninfective in animals (1), are completely inhibited from acting by the use of proper amounts of immune serum. The mechanism underlying this preventive power of adequate amounts of serum may be explained on the basis of facts deduced in preceding papers of this series (1, 3) and in the present article. We have shown that 3 x 107 m.i.u. of active virus contains a sufficient amount of antigen to induce immunity without the necessity of its multiplication in the animal body. This has been fully established by the similar degree of resistance brought about by 3 x 107 m.i.u. of virus formolized to a degree in

  19. Antiviral activity of Aloe vera against herpes simplex virus type 2: An ...

    African Journals Online (AJOL)

    In this study we tested the antiviral activity of a crude hot glycerine extract of Aloe vera gel which was grown in Bushehr (Southwest of Iran) against HSV-2 replication in Vero cell line. The extract showed antiviral activity against HSV-2 not only before attachment and entry of virus to the Vero cells but also on post attachment ...

  20. A reporter system for assaying influenza virus RNP functionality based on secreted Gaussia luciferase activity

    Directory of Open Access Journals (Sweden)

    Wu Xiaobing

    2011-01-01

    Full Text Available Abstract Background Influenza A virus can infect a wide variety of animal species including humans, pigs, birds and other species. Viral ribonucleoprotein (vRNP was involved in genome replication, transcription and host adaptation. Currently, firefly luciferase (Fluc reporter system was used in vRNP functional assay. However, its limitation for the testing by virus infection resulted in an increased need for rapid, sensitive, and biosafe techniques. Here, an influenza A virus UTR-driven gene reporter for vRNP assay based on secreted Gaussia luciferase (Gluc activity was evaluated. Results By measuring Gluc levels in supernatants, reporter gene activity could be detected and quantitated after either reconstitution of influenza A virus polymerase complex or viral infection of 293T and A549 cells, respectively. As compared with Fluc reporter, Gluc-based reporter was heat-tolerant (65°C for 30 min and produced 50-fold higher bioluminescent activity at 24 h posttransfection. Signals generated by Gluc reporter gene could be detected as early as 6 h post-infection and accumulated with time. Testing by viral infection, stronger signals were detected by Gluc reporter at a MOI of 0.001 than that of 1 and the effects of PB2-627K/E or amantadine on influenza vRNP activity were elucidated more effectively by the Gluc reporter system. Conclusions This approach provided a rapid, sensitive, and biosafe assay of influenza vRNP function, particularly for the highly pathogenic avian influenza viruses.

  1. Signaling through RIG-I and type I interferon receptor: Immune activation by Newcastle disease virus in man versus immune evasion by Ebola virus (Review).

    Science.gov (United States)

    Schirrmacher, Volker

    2015-07-01

    In this review, two types of RNA viruses are compared with regard to the type I interferon (IFN) response in order to obtain a better understanding of the molecular mechanisms of immune activation or evasion. Upon human infection, both viruses exert either beneficial or detrimental effects. The Newcastle disease virus (NDV), is a type strain for avian paramyxoviruses, while the Ebola virus (EBOV), is a virus affecting primates. During evolution, both viruses specifically adapted to their respective hosts, acquiring sophisticated viral escape mechanisms. Two types of receptors play an important role in the life cycle of these two viruses: cytoplasmic retinoic acid‑inducible gene I (RIG‑I) and membrane expressed type I IFN receptor (IFNAR). In mouse and human cells, NDV is a strong inducer of the type I IFN response. The early phase of this is initiated by signaling through RIG‑I and the late response by signaling through IFNAR. EBOV does not induce type I IFN responses in humans as it has viral proteins that specifically and strongly interfere with RIG‑I and IFNAR signaling, as well as immune activation. In this review, we discuss whether the beneficial effects of one virus can be exploited in the fight against the detrimental effects of the other.

  2. Inhibitory Activity of Synthetic Peptide Antibiotics on Feline Immunodeficiency Virus Infectivity In Vitro

    Science.gov (United States)

    Ma, Jia; Kennedy-Stoskopf, Suzanne; Jaynes, Jesse M.; Thurmond, Linda M.; Tompkins, Wayne A.

    2002-01-01

    Natural peptide antibiotics are part of host innate immunity against a wide range of microbes, including some viruses. Synthetic peptides modeled after natural peptide antibiotics interfere with microbial membranes and are termed peptidyl membrane-interactive molecules (peptidyl-MIM [Demegen Inc, Pittsburgh, Pa.]). Sixteen peptidyl-MIM candidates were tested for activity against feline immunodeficiency virus (FIV) on infected CrFK cells. Three of them (D4E1, DC1, and D1D6) showed potent anti-FIV activity in chronically infected CrFK cells as measured by decreased reverse transcriptase (RT) activity, having 50% inhibitory concentrations of 0.46, 0.75, and 0.94 μM, respectively, which were approximately 10 times lower than their direct cytotoxic concentrations. Treatment of chronically infected CrFK cells with 2 μM D4E1 for 3 days completely reversed virus-induced cytopathic effect. Immunofluorescence revealed reduced p26 staining in these cells. Treatment of chronically infected CrFK cells with 2 μM D4E1 suppressed virus production (∼50%) for up to 7 days, The virions from the D4E1-treated culture had impaired infectivity, as measured by the 50% tissue culture infectious dose and nested PCR analysis of proviral DNA. However, these noninfectious virions were able to bind and internalize, suggesting a defect at some postentry step. After chronically infected CrFK cells were treated with D4E1 for 24 h, increased cell-associated mature p26 Gag and decreased extracellular virus-associated p26 Gag were observed by Western blot analysis, suggesting that virus assembly and/or release may be blocked by D4E1 treatment, whereas virus binding, penetration, RNA synthesis, and protein synthesis appear to be unaffected. Synthetic peptide antibiotics may be useful tools in the search for antiviral drugs having a wide therapeutic window for host cells. PMID:12208971

  3. Predicting receptor functionality of signaling lymphocyte activation molecule for measles virus hemagglutinin by docking simulation.

    Science.gov (United States)

    Suzuki, Yoshiyuki

    2017-05-01

    Predicting susceptibility of various species to a virus assists assessment of risk of interspecies transmission. Evaluation of receptor functionality may be useful in screening for susceptibility. In this study, docking simulation was conducted for measles virus hemagglutinin (MV-H) and immunoglobulin-like variable domain of signaling lymphocyte activation molecule (SLAM-V). It was observed that the docking scores for MV-H and SLAM-V correlated with the activity of SLAM as an MV receptor. These results suggest that the receptor functionality may be predicted from the docking scores of virion surface proteins and cellular receptor molecules. © 2017 The Societies and John Wiley & Sons Australia, Ltd.

  4. Zika Virus Infects, Activates, and Crosses Brain Microvascular Endothelial Cells, without Barrier Disruption

    Directory of Open Access Journals (Sweden)

    Michelle P. Papa

    2017-12-01

    Full Text Available Zika virus (ZIKV has been associated to central nervous system (CNS harm, and virus was detected in the brain and cerebrospinal fluids of microcephaly and meningoencephalitis cases. However, the mechanism by which the virus reaches the CNS is unclear. Here, we addressed the effects of ZIKV replication in human brain microvascular endothelial cells (HBMECs, as an in vitro model of blood brain barrier (BBB, and evaluated virus extravasation and BBB integrity in an in vivo mouse experimental model. HBMECs were productively infected by African and Brazilian ZIKV strains (ZIKVMR766 and ZIKVPE243, which induce increased production of type I and type III IFN, inflammatory cytokines and chemokines. Infection with ZIKVMR766 promoted earlier cellular death, in comparison to ZIKVPE243, but infection with either strain did not result in enhanced endothelial permeability. Despite the maintenance of endothelial integrity, infectious virus particles crossed the monolayer by endocytosis/exocytosis-dependent replication pathway or by transcytosis. Remarkably, both viruses' strains infected IFNAR deficient mice, with high viral load being detected in the brains, without BBB disruption, which was only detected at later time points after infection. These data suggest that ZIKV infects and activates endothelial cells, and might reach the CNS through basolateral release, transcytosis or transinfection processes. These findings further improve the current knowledge regarding ZIKV dissemination pathways.

  5. Zika Virus Infects, Activates, and Crosses Brain Microvascular Endothelial Cells, without Barrier Disruption

    Science.gov (United States)

    Papa, Michelle P.; Meuren, Lana M.; Coelho, Sharton V. A.; Lucas, Carolina G. de Oliveira; Mustafá, Yasmin M.; Lemos Matassoli, Flavio; Silveira, Paola P.; Frost, Paula S.; Pezzuto, Paula; Ribeiro, Milene R.; Tanuri, Amilcar; Nogueira, Mauricio L.; Campanati, Loraine; Bozza, Marcelo T.; Paula Neto, Heitor A.; Pimentel-Coelho, Pedro M.; Figueiredo, Claudia P.; de Aguiar, Renato S.; de Arruda, Luciana B.

    2017-01-01

    Zika virus (ZIKV) has been associated to central nervous system (CNS) harm, and virus was detected in the brain and cerebrospinal fluids of microcephaly and meningoencephalitis cases. However, the mechanism by which the virus reaches the CNS is unclear. Here, we addressed the effects of ZIKV replication in human brain microvascular endothelial cells (HBMECs), as an in vitro model of blood brain barrier (BBB), and evaluated virus extravasation and BBB integrity in an in vivo mouse experimental model. HBMECs were productively infected by African and Brazilian ZIKV strains (ZIKVMR766 and ZIKVPE243), which induce increased production of type I and type III IFN, inflammatory cytokines and chemokines. Infection with ZIKVMR766 promoted earlier cellular death, in comparison to ZIKVPE243, but infection with either strain did not result in enhanced endothelial permeability. Despite the maintenance of endothelial integrity, infectious virus particles crossed the monolayer by endocytosis/exocytosis-dependent replication pathway or by transcytosis. Remarkably, both viruses' strains infected IFNAR deficient mice, with high viral load being detected in the brains, without BBB disruption, which was only detected at later time points after infection. These data suggest that ZIKV infects and activates endothelial cells, and might reach the CNS through basolateral release, transcytosis or transinfection processes. These findings further improve the current knowledge regarding ZIKV dissemination pathways. PMID:29312238

  6. Memory B cells and CD8⁺ lymphocytes do not control seasonal influenza A virus replication after homologous re-challenge of rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Timothy D Carroll

    Full Text Available This study sought to define the role of memory lymphocytes in the protection from homologous influenza A virus re-challenge in rhesus macaques. Depleting monoclonal antibodies (mAb were administered to the animals prior to their second experimental inoculation with a human seasonal influenza A virus strain. Treatment with either anti-CD8α or anti-CD20 mAbs prior to re-challenge had minimal effect on influenza A virus replication. Thus, in non-human primates with pre-existing anti-influenza A antibodies, memory B cells and CD8α⁺ T cells do not contribute to the control of virus replication after re-challenge with a homologous strain of influenza A virus.

  7. Inhibitors of the influenza A virus M2 proton channel discovered using a high-throughput yeast growth restoration assay.

    Directory of Open Access Journals (Sweden)

    Aruna D Balgi

    Full Text Available The M2 proton channel of the influenza A virus is the target of the anti-influenza drugs amantadine and rimantadine. The effectiveness of these drugs has been dramatically limited by the rapid spread of drug resistant mutations, mainly at sites S31N, V27A and L26F in the pore of the channel. Despite progress in designing inhibitors of V27A and L26F M2, there are currently no drugs targeting these mutated channels in clinical trials. Progress in developing new drugs has been hampered by the lack of a robust assay with sufficient throughput for discovery of new active chemotypes among chemical libraries and sufficient sensitivity to provide the SAR data essential for their improvement and development as drugs. In this study we adapted a yeast growth restoration assay, in which expression of the M2 channel inhibits yeast growth and exposure to an M2 channel inhibitor restores growth, into a robust and sensitive high-throughput screen for M2 channel inhibitors. A screen of over 250,000 pure chemicals and semi-purified fractions from natural extracts identified 21 active compounds comprising amantadine, rimantadine, 13 related adamantanes and 6 non-adamantanes. Of the non-adamantanes, hexamethylene amiloride and a triazine derivative represented new M2 inhibitory chemotypes that also showed antiviral activity in a plaque reduction assay. Of particular interest is the fact that the triazine derivative was not sufficiently potent for detection as an inhibitor in the traditional two electrode voltage clamp assay for M2 channel activity, but its discovery in the yeast assay led to testing of analogues of which one was as potent as amantadine.

  8. Adenovirus vectors lacking virus-associated RNA expression enhance shRNA activity to suppress hepatitis C virus replication

    Science.gov (United States)

    Pei, Zheng; Shi, Guoli; Kondo, Saki; Ito, Masahiko; Maekawa, Aya; Suzuki, Mariko; Saito, Izumu; Suzuki, Tetsuro; Kanegae, Yumi

    2013-12-01

    First-generation adenovirus vectors (FG AdVs) expressing short-hairpin RNA (shRNA) effectively downregulate the expressions of target genes. However, this vector, in fact, expresses not only the transgene product, but also virus-associated RNAs (VA RNAs) that disturb cellular RNAi machinery. We have established a production method for VA-deleted AdVs lacking expression of VA RNAs. Here, we showed that the highest shRNA activity was obtained when the shRNA was inserted not at the popularly used E1 site, but at the E4 site. We then compared the activities of shRNAs against hepatitis C virus (HCV) expressed from VA-deleted AdVs or conventional AdVs. The VA-deleted AdVs inhibited HCV production much more efficiently. Therefore, VA-deleted AdVs were more effective than the currently used AdVs for shRNA downregulation, probably because of the lack of competition between VA RNAs and the shRNAs. These VA-deleted AdVs might enable more effective gene therapies for chronic hepatitis C.

  9. Influence of the water molecules near surface of viral protein on virus activation process

    Energy Technology Data Exchange (ETDEWEB)

    O, Shepelenko S; S, Salnikov A; V, Rak S; P, Goncharova E; B, Ryzhikov A, E-mail: shep@vector.nsc.r, E-mail: shep@ngs.r [Federal State Research Institution State Research Center of Virology and Biotechnology VECTOR of the Federal Service for Surveillance in Consumer Rights Protection and Human Well-being (FSRI SRC VB VECTOR) Koltsovo, Novosibirsk Region (Russian Federation)

    2009-06-01

    The infection of a cell with influenza virus comprises the stages of receptor binding to the cell membrane, endocytosis of virus particle, and fusion of the virus envelope and cell endosome membrane, which is determined by the conformational changes in hemagglutinin, a virus envelope protein, caused by pH decrease within the endosome. The pH value that induces conformation rearrangements of hemagglutinin molecule considerably varies for different influenza virus strains, first and foremost, due to the differences in amino acid structure of the corresponding proteins. The main goal of this study was to construct a model making it possible to assess the critical pH value characterizing the fusogenic activity of influenza virus hemagglutinin from the data on hemagglutinin structure and experimental verification of this model. Under this model, we assume that when the electrostatic force between interacting hemagglutinin molecules in the virus envelop exceeds a certain value, the hemagglutinin HA1 subunits are arranged so that they form a cavity sufficient for penetration of water molecules. This event leads to an irreversible hydration of the inner fragments of hemagglutinin molecule in a trimer and to the completion of conformational changes. The geometry of electrostatic field in hemagglutinin trimer was calculated taking into account the polarization effects near the interface of two dielectrics, aqueous medium and protein macromolecule. The critical pH values for the conformational changes in hemagglutinin were measured by the erythrocyte hemolysis induced by influenza virus particles when decreasing pH. The critical pH value conditionally separating the pH range into the regions with and without the conformational changes was calculated for several influenza virus H1N1 and H3N2 strains based on the data on the amino acid structure of the corresponding hemagglutinin molecules. Comparison of the theoretical and experimental values of critical pH values for

  10. Influence of the water molecules near surface of viral protein on virus activation process

    International Nuclear Information System (INIS)

    O, Shepelenko S; S, Salnikov A; V, Rak S; P, Goncharova E; B, Ryzhikov A

    2009-01-01

    The infection of a cell with influenza virus comprises the stages of receptor binding to the cell membrane, endocytosis of virus particle, and fusion of the virus envelope and cell endosome membrane, which is determined by the conformational changes in hemagglutinin, a virus envelope protein, caused by pH decrease within the endosome. The pH value that induces conformation rearrangements of hemagglutinin molecule considerably varies for different influenza virus strains, first and foremost, due to the differences in amino acid structure of the corresponding proteins. The main goal of this study was to construct a model making it possible to assess the critical pH value characterizing the fusogenic activity of influenza virus hemagglutinin from the data on hemagglutinin structure and experimental verification of this model. Under this model, we assume that when the electrostatic force between interacting hemagglutinin molecules in the virus envelop exceeds a certain value, the hemagglutinin HA1 subunits are arranged so that they form a cavity sufficient for penetration of water molecules. This event leads to an irreversible hydration of the inner fragments of hemagglutinin molecule in a trimer and to the completion of conformational changes. The geometry of electrostatic field in hemagglutinin trimer was calculated taking into account the polarization effects near the interface of two dielectrics, aqueous medium and protein macromolecule. The critical pH values for the conformational changes in hemagglutinin were measured by the erythrocyte hemolysis induced by influenza virus particles when decreasing pH. The critical pH value conditionally separating the pH range into the regions with and without the conformational changes was calculated for several influenza virus H1N1 and H3N2 strains based on the data on the amino acid structure of the corresponding hemagglutinin molecules. Comparison of the theoretical and experimental values of critical pH values for

  11. Virus-associated activation of innate immunity induces rapid disruption of Peyer's patches in mice.

    Science.gov (United States)

    Heidegger, Simon; Anz, David; Stephan, Nicolas; Bohn, Bernadette; Herbst, Tina; Fendler, Wolfgang Peter; Suhartha, Nina; Sandholzer, Nadja; Kobold, Sebastian; Hotz, Christian; Eisenächer, Katharina; Radtke-Schuller, Susanne; Endres, Stefan; Bourquin, Carole

    2013-10-10

    Early in the course of infection, detection of pathogen-associated molecular patterns by innate immune receptors can shape the subsequent adaptive immune response. Here we investigate the influence of virus-associated innate immune activation on lymphocyte distribution in secondary lymphoid organs. We show for the first time that virus infection of mice induces rapid disruption of the Peyer's patches but not of other secondary lymphoid organs. The observed effect was not dependent on an active infectious process, but due to innate immune activation and could be mimicked by virus-associated molecular patterns such as the synthetic double-stranded RNA poly(I:C). Profound histomorphologic changes in Peyer's patches were associated with depletion of organ cellularity, most prominent among the B-cell subset. We demonstrate that the disruption is entirely dependent on type I interferon (IFN). At the cellular level, we show that virus-associated immune activation by IFN-α blocks B-cell trafficking to the Peyer's patches by downregulating expression of the homing molecule α4β7-integrin. In summary, our data identify a mechanism that results in type I IFN-dependent rapid but reversible disruption of intestinal lymphoid organs during systemic viral immune activation. We propose that such rerouted lymphocyte trafficking may impact the development of B-cell immunity to systemic viral pathogens.

  12. Direct Activation of Innate and Antigen-Presenting Functions of Microglia following Infection with Theiler's Virus

    Science.gov (United States)

    Olson, Julie K.; Girvin, Ann M.; Miller, Stephen D.

    2001-01-01

    Microglia are resident central nervous system (CNS) macrophages. Theiler's murine encephalomyelitis virus (TMEV) infection of SJL/J mice causes persistent infection of CNS microglia, leading to the development of a chronic-progressive CD4+ T-cell-mediated autoimmune demyelinating disease. We asked if TMEV infection of microglia activates their innate immune functions and/or activates their ability to serve as antigen-presenting cells for activation of T-cell responses to virus and endogenous myelin epitopes. The results indicate that microglia lines can be persistently infected with TMEV and that infection significantly upregulates the expression of cytokines involved in innate immunity (tumor necrosis factor alpha, interleukin-6 [IL-6], IL-18, and, most importantly, type I interferons) along with upregulation of major histocompatibility complex class II, IL-12, and various costimulatory molecules (B7-1, B7-2, CD40, and ICAM-1). Most significantly, TMEV-infected microglia were able to efficiently process and present both endogenous virus epitopes and exogenous myelin epitopes to inflammatory CD4+ Th1 cells. Thus, TMEV infection of microglia activates these cells to initiate an innate immune response which may lead to the activation of naive and memory virus- and myelin-specific adaptive immune responses within the CNS. PMID:11559811

  13. The adaptor protein MITA links virus-sensing receptors to IRF3 transcription factor activation.

    Science.gov (United States)

    Zhong, Bo; Yang, Yan; Li, Shu; Wang, Yan-Yi; Li, Ying; Diao, Feici; Lei, Caoqi; He, Xiao; Zhang, Lu; Tien, Po; Shu, Hong-Bing

    2008-10-17

    Viral infection triggers activation of transcription factors such as NF-kappaB and IRF3, which collaborate to induce type I interferons (IFNs) and elicit innate antiviral response. Here, we identified MITA as a critical mediator of virus-triggered type I IFN signaling by expression cloning. Overexpression of MITA activated IRF3, whereas knockdown of MITA inhibited virus-triggered activation of IRF3, expression of type I IFNs, and cellular antiviral response. MITA was found to localize to the outer membrane of mitochondria and to be associated with VISA, a mitochondrial protein that acts as an adaptor in virus-triggered signaling. MITA also interacted with IRF3 and recruited the kinase TBK1 to the VISA-associated complex. MITA was phosphorylated by TBK1, which is required for MITA-mediated activation of IRF3. Our results suggest that MITA is a critical mediator of virus-triggered IRF3 activation and IFN expression and further demonstrate the importance of certain mitochondrial proteins in innate antiviral immunity.

  14. Antiviral activity of four types of bioflavonoid against dengue virus type-2

    Directory of Open Access Journals (Sweden)

    Zandi Keivan

    2011-12-01

    Full Text Available Abstract Background Dengue is a major mosquito-borne disease currently with no effective antiviral or vaccine available. Effort to find antivirals for it has focused on bioflavonoids, a plant-derived polyphenolic compounds with many potential health benefits. In the present study, antiviral activity of four types of bioflavonoid against dengue virus type -2 (DENV-2 in Vero cell was evaluated. Anti-dengue activity of these compounds was determined at different stages of DENV-2 infection and replication cycle. DENV replication was measured by Foci Forming Unit Reduction Assay (FFURA and quantitative RT-PCR. Selectivity Index value (SI was determined as the ratio of cytotoxic concentration 50 (CC50 to inhibitory concentration 50 (IC50 for each compound. Results The half maximal inhibitory concentration (IC50 of quercetin against dengue virus was 35.7 μg mL-1 when it was used after virus adsorption to the cells. The IC50 decreased to 28.9 μg mL-1 when the cells were treated continuously for 5 h before virus infection and up to 4 days post-infection. The SI values for quercetin were 7.07 and 8.74 μg mL-1, respectively, the highest compared to all bioflavonoids studied. Naringin only exhibited anti-adsorption effects against DENV-2 with IC50 = 168.2 μg mL-1 and its related SI was 1.3. Daidzein showed a weak anti-dengue activity with IC50 = 142.6 μg mL-1 when the DENV-2 infected cells were treated after virus adsorption. The SI value for this compound was 1.03. Hesperetin did not exhibit any antiviral activity against DENV-2. The findings obtained from Foci Forming Unit Reduction Assay (FFURA were corroborated by findings of the qRT-PCR assays. Quercetin and daidzein (50 μg mL-1 reduced DENV-2 RNA levels by 67% and 25%, respectively. There was no significant inhibition of DENV-2 RNA levels with naringin and hesperetin. Conclusion Results from the study suggest that only quercetin demonstrated significant anti-DENV-2 inhibitory activities. Other

  15. Evaluation of antiviral activity of South American plant extracts against herpes simplex virus type 1 and rabies virus.

    Science.gov (United States)

    Müller, Vanessa; Chávez, Juliana H; Reginatto, Flávio H; Zucolotto, Silvana M; Niero, Rivaldo; Navarro, Dionezine; Yunes, Rosendo A; Schenkel, Eloir P; Barardi, Célia R M; Zanetti, Carlos R; Simões, Cláudia M O

    2007-10-01

    This paper describes the screening of different South American plant extracts and fractions. Aqueous and organic extracts were prepared and tested for antiherpetic (HSV-1, KOS and 29R strains) and antirabies (PV strain) activities. The evaluation of the potential antiviral activity of these extracts was performed by using an MTT assay for HSV-1, and by a viral cytopathic effect (CPE) inhibitory method for rabies virus (RV). The results were expressed as 50% cytotoxicity (CC(50)) for MTT assay and 50% effective (EC(50)) concentrations for CPE, and with them it was possible to calculate the selectivity indices (SI = CC(50)/EC(50)) of each tested material. From the 18 extracts/fractions tested, six extracts and four fractions showed antiviral action. Ilex paraguariensis, Lafoensia pacari, Passiflora edulis, Rubus imperialis and Slonea guianensis showed values of SI > 7 against HSV-1 KOS and 29-R strains and Alamanda schottii showed a SI of 5.6 against RV, PV strain.

  16. Murine Hepatitis Virus nsp14 Exoribonuclease Activity Is Required for Resistance to Innate Immunity.

    Science.gov (United States)

    Case, James Brett; Li, Yize; Elliott, Ruth; Lu, Xiaotao; Graepel, Kevin W; Sexton, Nicole R; Smith, Everett Clinton; Weiss, Susan R; Denison, Mark R

    2018-01-01

    Coronaviruses (CoVs) are positive-sense RNA viruses that infect numerous mammalian and avian species and are capable of causing severe and lethal disease in humans. CoVs encode several innate immune antagonists that counteract the host innate immune response to facilitate efficient viral replication. CoV nonstructural protein 14 (nsp14) encodes 3'-to-5' exoribonuclease activity (ExoN), which performs a proofreading function and is required for high-fidelity replication. Outside of the order Nidovirales , arenaviruses are the only RNA viruses that encode an ExoN, which functions to degrade double-stranded RNA (dsRNA) replication intermediates. In this study, we tested the hypothesis that CoV ExoN also functions to antagonize the innate immune response. We demonstrate that viruses lacking ExoN activity [ExoN(-)] are sensitive to cellular pretreatment with interferon beta (IFN-β) in a dose-dependent manner. In addition, ExoN(-) virus replication was attenuated in wild-type bone marrow-derived macrophages (BMMs) and partially restored in interferon alpha/beta receptor-deficient (IFNAR -/- ) BMMs. ExoN(-) virus replication did not result in IFN-β gene expression, and in the presence of an IFN-β-mediated antiviral state, ExoN(-) viral RNA levels were not substantially reduced relative to those of untreated samples. However, ExoN(-) virus generated from IFN-β-pretreated cells had reduced specific infectivity and decreased relative fitness, suggesting that ExoN(-) virus generated during an antiviral state is less viable to establish a subsequent infection. Overall, our data suggest murine hepatitis virus (MHV) ExoN activity is required for resistance to the innate immune response, and antiviral mechanisms affecting the viral RNA sequence and/or an RNA modification act on viruses lacking ExoN activity. IMPORTANCE CoVs encode multiple antagonists that prevent or disrupt an efficient innate immune response. Additionally, no specific antiviral therapies or vaccines

  17. Microbial Translocation Is Associated with Extensive Immune Activation in Dengue Virus Infected Patients with Severe Disease

    NARCIS (Netherlands)

    C.A.M. van de Weg (Cornelia A.M.); C.S. Pannuti (Cláudio); E.S. Affonso De Araujo (Evaldo); H.J. van den Ham; A.C. Andeweg (Arno); L.S.V. Boas (Lucy); A.C. Felix (Alvina); K.I. Carvalho (Karina); A.M. de Matos (Andreia); J.E. Levi (José); C.M. Romano (Camila); C.C. Centrone (Cristiane); C.L. de Lima Rodrigues (Celia); E. Luna (Expedito); E.C.M. van Gorp (Eric); A.D.M.E. Osterhaus (Albert); B.E.E. Martina (Byron); E.G. Kallas (Esper)

    2013-01-01

    textabstractBackground:Severe dengue virus (DENV) disease is associated with extensive immune activation, characterized by a cytokine storm. Previously, elevated lipopolysaccharide (LPS) levels in dengue were found to correlate with clinical disease severity. In the present cross-sectional study we

  18. Anti-herpes simplex virus activity of extracts from the culinary herbs ...

    African Journals Online (AJOL)

    This study demonstrates anti-herpes simplex virus activity of dichloromethane and methanol extracts of Ocimum sanctum L., Ocimum basilicum L. and Ocimum americanum L. Green monkey kidney cells were protected from HSV-2 infection by the dichloromethane extract of O. americanum L. and the methanol extract of O.

  19. Antiviral activity of Dianthus superbusn L. against hepatitis B virus in ...

    African Journals Online (AJOL)

    Background: Hepatitis is a viral infection of hepatitis B virus (HBV). Limitations of drug used in the management of it opens the interest related to alternative medicine. The given study deals with the antiviral activity of Dianthus superbusn L. (DSL) against HBV in vitro & in vivo. Material and Methods: In vitro study liver cell line ...

  20. Anti-herpes simplex virus activity of extracts from the culinary herbs ...

    African Journals Online (AJOL)

    user

    2011-01-31

    Jan 31, 2011 ... This study demonstrates anti-herpes simplex virus activity of dichloromethane and methanol extracts of Ocimum sanctum L., Ocimum basilicum L. and Ocimum americanum L. Green monkey kidney cells were protected from HSV-2 infection by the dichloromethane extract of O. americanum L. and the.

  1. Hyperferritinaemia in dengue virus infected patients is associated with immune activation and coagulation disturbances

    NARCIS (Netherlands)

    van de Weg, Cornelia A. M.; Huits, Ralph M. H. G.; Pannuti, Cláudio S.; Brouns, Rosalba M.; van den Berg, Riemsdijk W. A.; van den Ham, Henk-Jan; Martina, Byron E. E.; Osterhaus, Albert D. M. E.; Netea, Mihai G.; Meijers, Joost C. M.; van Gorp, Eric C. M.; Kallas, Esper G.

    2014-01-01

    During a dengue outbreak on the Caribbean island Aruba, highly elevated levels of ferritin were detected in dengue virus infected patients. Ferritin is an acute-phase reactant and hyperferritinaemia is a hallmark of diseases caused by extensive immune activation, such as haemophagocytic

  2. Antiviral activity of Petiveria alliacea against the bovine viral diarrhea virus.

    Science.gov (United States)

    Ruffa, M J; Perusina, M; Alfonso, V; Wagner, M L; Suriano, M; Vicente, C; Campos, R; Cavallaro, L

    2002-07-01

    Natural products are a relevant source of antiviral drugs. Five medicinal plants used in Argentina have been assayed to detect inhibition of viral growth. Antiviral activity of the infusions and methanolic extracts of Aristolochia macroura, Celtis spinosa, Plantago major, Schinus areira, Petiveria alliacea and four extracts obtained from the leaves and stems of the last plant were evaluated by the plaque assay. P. alliacea, unlike A. macroura, C. spinosa, P. major and S. areira, inhibited bovine viral diarrhea virus (BVDV) replication. Neither P. alliacea nor the assays of the other plants were active against herpes simplex virus type 1, poliovirus type 1, adenovirus serotype 7 and vesicular stomatitis virus type 1. Four extracts of P. alliacea were assayed to detect anti-BVDV activity. Ethyl acetate (EC(50) of 25 microg/ml) and dichloromethane (EC(50) of 43 microg/ml) extracts were active; moreover, promising SI (IC(50)/EC(50)) values were obtained. BVDV is highly prevalent in the cattle population, there are no antiviral compounds available; additionally, it is a viral model of the hepatitis C virus. For these reasons and in view of the results obtained, the isolation and characterization of the antiviral components present in the P. alliacea extracts is worth carrying out in the future. Copyright 2002 S. Karger AG, Basel

  3. Eastern equine encephalomyelitis virus and Culiseta melanura activity at the Patuxent Wildlife Research Center, 1985-90.

    Science.gov (United States)

    Pagac, B B; Turell, M J; Olsen, G H

    1992-09-01

    Mosquito population densities, virus isolations and seroconversion in sentinel quail were used to monitor eastern equine encephalomyelitis virus (EEE) activity at the Patuxent Wildlife Research Center, Laurel, Maryland, from 1985 through 1990. A dramatic increase in the number of Culiseta melanura collected in 1989, as compared with the 3 previous years, was associated with virus isolations from this species (5/75 pools; n = 542 mosquitoes) and with seroconversion in sentinel quail (4/22 birds positive). This was the first detection of EEE virus activity in this area since a 1984 EEE outbreak killed 7 whooping cranes.

  4. Persistent virus infection despite chronic cytotoxic T-lymphocyte activation in gamma interferon-deficient mice infected with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Bartholdy, C; Christensen, Jan Pravsgaard; Wodarz, D

    2000-01-01

    The role of gamma interferon (IFN-gamma) in the permanent control of infection with a noncytopathic virus was studied by comparing immune responses in wild-type and IFN-gamma-deficient (IFN-gamma -/-) mice infected with a slowly invasive strain of lymphocytic choriomeningitis virus (LCMV Armstrong...... in wild-type mice. These findings indicate that in the absence of IFN-gamma, CTLs cannot clear the infection and are kept permanently activated by the continuous presence of live virus, resulting in a delicate new balance between viral load and immunity. This interpretation of our findings is supported......). While wild-type mice rapidly cleared the infection, IFN-gamma -/- mice became chronically infected. Virus persistence in the latter mice did not reflect failure to generate cytotoxic T-lymphocyte (CTL) effectors, as an unimpaired primary CTL response was observed. Furthermore, while ex vivo CTL activity...

  5. Epstein-Barr virus DNA loads in adult human immunodeficiency virus type 1-infected patients receiving highly active antiretroviral therapy

    Science.gov (United States)

    Ling, Paul D.; Vilchez, Regis A.; Keitel, Wendy A.; Poston, David G.; Peng, Rong Sheng; White, Zoe S.; Visnegarwala, Fehmida; Lewis, Dorothy E.; Butel, Janet S.

    2003-01-01

    Patients with human immunodeficiency virus type 1 (HIV-1) infection are at high risk of developing Epstein-Barr virus (EBV)-associated lymphoma. However, little is known of the EBV DNA loads in patients receiving highly active antiretroviral therapy (HAART). Using a real-time quantitative polymerase chain reaction assay, we demonstrated that significantly more HIV-1-infected patients receiving HAART than HIV-1-uninfected volunteers had detectable EBV DNA in blood (57 [81%] of 70 vs. 11 [16%] of 68 patients; P=.001) and saliva (55 [79%] of 68 vs. 37 [54%] of 68 patients; P=.002). The mean EBV loads in blood and saliva samples were also higher in HIV-1-infected patients than in HIV-1-uninfected volunteers (P=.001). The frequency of EBV detection in blood was associated with lower CD4+ cell counts (P=.03) among HIV-1-infected individuals, although no differences were observed in the EBV DNA loads in blood or saliva samples in the HIV-1-infected group. Additional studies are needed to determine whether EBV-specific CD4+ and CD8+ cells play a role in the pathogenesis of EBV in HIV-1-infected patients receiving HAART.

  6. Antiviral effects of Psidium guajava Linn. (guava) tea on the growth of clinical isolated H1N1 viruses: its role in viral hemagglutination and neuraminidase inhibition.

    Science.gov (United States)

    Sriwilaijaroen, Nongluk; Fukumoto, Syuichi; Kumagai, Kenji; Hiramatsu, Hiroaki; Odagiri, Takato; Tashiro, Masato; Suzuki, Yasuo

    2012-05-01

    Rapid evolution of influenza RNA virus has resulted in limitation of vaccine effectiveness, increased emergence of drug-resistant viruses and occurrence of pandemics. A new effective antiviral is therefore needed for control of the highly mutative influenza virus. Teas prepared by the infusion method were tested for their anti-influenza activity against clinical influenza A (H1N1) isolates by a 19-h influenza growth inhibition assay with ST6Gal I-expressing MDCK cells (AX4 cells) using fluorogenic quantification and chromogenic visualization. Guava tea markedly inhibited the growth of A/Narita/1/2009 (amantadine-resistant pandemic 2009 strain) at an IC(50) of 0.05% and the growth of A/Yamaguchi/20/06 (sensitive strain) and A/Kitakyushu/10/06 (oseltamivir-resistant strain) at similar IC(50) values ranging from 0.24% to 0.42% in AX4 cells, being 3.4- to 5.4-fold more potent than green tea (IC(50) values: 0.27% for the 2009 pandemic strain and 0.91% to 1.44% for the seasonal strains). In contrast to both teas, oseltamivir carboxylate (OC) demonstrated high potency against the growth of A/Narita/1/09 (IC(50) of 3.83nM) and A/Yamaguchi/20/06 (IC(50) of 11.57nM) but not against that of A/Kitakyushu/10/06 bearing a His274-to-Tyr substitution (IC(50) of 15.97μM). Immunofluorescence analysis under a confocal microscope indicated that both teas inhibited the most susceptible A/Narita/1/2009 virus at the initial stage of virus infection. This is consistent with results of direct inhibition assays showing that both teas inhibited viral hemagglutination at concentrations comparable to their growth inhibition concentrations but inhibited sialidase activity at about 8-times higher concentrations. Guava tea shows promise to be efficacious for control of epidemic and pandemic influenza viruses including oseltamivir-resistant strains, and its broad target blockage makes it less likely to lead to emergence of viral resistance. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Rabies virus expressing dendritic cell-activating molecules enhances the innate and adaptive immune response to vaccination.

    Science.gov (United States)

    Wen, Yongjun; Wang, Hualei; Wu, Hua; Yang, Fuhe; Tripp, Ralph A; Hogan, Robert J; Fu, Zhen F

    2011-02-01

    Our previous studies indicated that recruitment and/or activation of dendritic cells (DCs) is important in enhancing the protective immune responses against rabies virus (RABV) (L. Zhao, H. Toriumi, H. Wang, Y. Kuang, X. Guo, K. Morimoto, and Z. F. Fu, J. Virol. 84:9642-9648). To address the importance of DC activation for RABV vaccine efficacy, the genes for several DC recruitment and/or activation molecules, e.g., granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage-derived chemokine (MDC), and macrophage inflammatory protein 1α (MIP-1α), were individually cloned into RABV. The ability of these recombinant viruses to activate DCs was determined in vitro and in vivo. Infection of mouse bone marrow-derived DCs with each of the recombinant viruses resulted in DC activation, as shown by increased surface expression of CD11c and CD86 as well as an increased level of alpha interferon (IFN-α) production compared to levels observed after infection with the parent virus. Intramuscular infection of mice with each of the viruses recruited and/or activated more DCs and B cells in the periphery than infection with the parent virus, leading to the production of higher levels of virus-neutralizing antibodies. Furthermore, a single immunization with recombinant RABV expressing GM-CSF or MDC protected significantly more mice against intracerebral challenge with virulent RABV than did immunization with the parental virus. Yet, these viruses did not show more virulence than the parent virus, since direct intracerebral inoculation with each virus at up to 1 × 10(7) fluorescent focus units each did not induce any overt clinic symptom, such as abnormal behavior, or any neurological signs. Together, these data indicate that recombinant RABVs expressing these molecules activate/recruit DCs and enhance protective immune responses.

  8. Antiviral activity of silver nanoparticle/chitosan composites against H1N1 influenza A virus

    Science.gov (United States)

    Mori, Yasutaka; Ono, Takeshi; Miyahira, Yasushi; Nguyen, Vinh Quang; Matsui, Takemi; Ishihara, Masayuki

    2013-02-01

    Silver nanoparticle (Ag NP)/chitosan (Ch) composites with antiviral activity against H1N1 influenza A virus were prepared. The Ag NP/Ch composites were obtained as yellow or brown floc-like powders following reaction at room temperature in aqueous medium. Ag NPs (3.5, 6.5, and 12.9 nm average diameters) were embedded into the chitosan matrix without aggregation or size alternation. The antiviral activity of the Ag NP/Ch composites was evaluated by comparing the TCID50 ratio of viral suspensions treated with the composites to untreated suspensions. For all sizes of Ag NPs tested, antiviral activity against H1N1 influenza A virus increased as the concentration of Ag NPs increased; chitosan alone exhibited no antiviral activity. Size dependence of the Ag NPs on antiviral activity was also observed: antiviral activity was generally stronger with smaller Ag NPs in the composites. These results indicate that Ag NP/Ch composites interacting with viruses exhibit antiviral activity.

  9. Astrocytes play a key role in activation of microglia by persistent Borna disease virus infection

    Directory of Open Access Journals (Sweden)

    Sauder Christian

    2008-11-01

    Full Text Available Abstract Neonatal Borna disease virus (BDV infection of the rat brain is associated with microglial activation and damage to certain neuronal populations. Since persistent BDV infection of neurons is nonlytic in vitro, activated microglia have been suggested to be responsible for neuronal cell death in vivo. However, the mechanisms of activation of microglia in neonatally BDV-infected rat brains remain unclear. Our previous studies have shown that activation of microglia by BDV in culture requires the presence of astrocytes as neither the virus nor BDV-infected neurons alone activate microglia. Here, we evaluated the mechanisms whereby astrocytes can contribute to activation of microglia in neuron-glia-microglia mixed cultures. We found that persistent infection of neuronal cells leads to activation of uninfected astrocytes as measured by elevated expression of RANTES. Activation of astrocytes then produces activation of microglia as evidenced by increased formation of round-shaped, MHCI-, MHCII- and IL-6-positive microglia cells. Our analysis of possible molecular mechanisms of activation of astrocytes and/or microglia in culture indicates that the mediators of activation may be soluble heat-resistant, low molecular weight factors. The findings indicate that astrocytes may mediate activation of microglia by BDV-infected neurons. The data are consistent with the hypothesis that microglia activation in the absence of neuronal damage may represent initial steps in the gradual neurodegeneration observed in brains of neonatally BDV-infected rats.

  10. Host Plants Indirectly Influence Plant Virus Transmission by Altering Gut Cysteine Protease Activity of Aphid Vectors*

    Science.gov (United States)

    Pinheiro, Patricia V.; Ghanim, Murad; Rebelo, Ana Rita; Santos, Rogerio S.; Orsburn, Benjamin C.; Gray, Stewart

    2017-01-01

    The green peach aphid, Myzus persicae, is a vector of the Potato leafroll virus (PLRV, Luteoviridae), transmitted exclusively by aphids in a circulative manner. PLRV transmission efficiency was significantly reduced when a clonal lineage of M. persicae was reared on turnip as compared with the weed physalis, and this was a transient effect caused by a host-switch response. A trend of higher PLRV titer in physalis-reared aphids as compared with turnip-reared aphids was observed at 24 h and 72 h after virus acquisition. The major difference in the proteomes of these aphids was the up-regulation of predicted lysosomal enzymes, in particular the cysteine protease cathepsin B (cathB), in aphids reared on turnip. The aphid midgut is the site of PLRV acquisition, and cathB and PLRV localization were starkly different in midguts of the aphids reared on the two host plants. In viruliferous aphids that were reared on turnip, there was near complete colocalization of cathB and PLRV at the cell membranes, which was not observed in physalis-reared aphids. Chemical inhibition of cathB restored the ability of aphids reared on turnip to transmit PLRV in a dose-dependent manner, showing that the increased activity of cathB and other cysteine proteases at the cell membrane indirectly decreased virus transmission by aphids. Understanding how the host plant influences virus transmission by aphids is critical for growers to manage the spread of virus among field crops. PMID:27932519

  11. Dengue Virus Type 2: Protein Binding and Active Replication in Human Central Nervous System Cells

    Directory of Open Access Journals (Sweden)

    Ma Isabel Salazar

    2013-01-01

    Full Text Available An increased number of dengue cases with neurological complications have been reported in recent years. The lack of reliable animal models for dengue has hindered studies on dengue virus (DENV pathogenesis and cellular tropism in vivo. We further investigate the tropism of DENV for the human central nervous system (CNS, characterizing DENV interactions with cell surface proteins in human CNS cells by virus overlay protein binding assays (VOPBA and coimmunoprecipitations. In VOPBA, three membrane proteins (60, 70, and 130 kDa from the gray matter bound the entire virus particle, whereas only a 70 kDa protein bound in white matter. The coimmunoprecipitation assays revealed three proteins from gray matter consistently binding virus particles, one clearly distinguishable protein (~32 kDa and two less apparent proteins (100 and 130 kDa. Monoclonal anti-NS3 targeted the virus protein in primary cell cultures of human CNS treated with DENV-2, which also stained positive for NeuH, a neuron-specific marker. Thus, our results indicate (1 that DENV-2 exhibited a direct tropism for human neurons and (2 that human neurons sustain an active DENV replication as was demonstrated by the presence of the NS3 viral antigen in primary cultures of these cells treated with DENV-2.

  12. Antiviral activity of Aloe hijazensis against some haemagglutinating viruses infection and its phytoconstituents.

    Science.gov (United States)

    Abd-Alla, Howaida I; Abu-Gabal, Nagat S; Hassan, Amal Z; El-Safty, Mounir M; Shalaby, Nagwa M M

    2012-08-01

    Evaluation of the antiviral activities of flowers, flower-peduncles, leaves, and roots of Aloe hijazensis against haemagglutinating viruses of avian paramyxovirus type-1 (APMV-1), avian influenza virus type A (AI-H5N1), Newcastle disease virus (NDV), and egg-drop syndrome virus (EDSV) in specific pathogen free (SPF) chicken embryos were carried out. Extract of the flowers and leaves showed relatively higher activity than the extracts of other plant parts. Thirteen compounds were isolated from both the flowers and flower-peduncles of A. hijazensis. The isolated compounds were classified into: five anthraquinones; ziganein, ziganein-5-methyl ether, aloesaponarin I, chrysophanol, aloe-emodin, one dihydroisocoumarin; feralolide, four flavonoids; homoplantaginin, isoorientin, luteolin 7-glucuronopyranoside, isovitexin, one phenolic acid; p-coumaric acid, the anthrone; barbaloin together with aloenin. Eleven compounds were attributed to the flowers and seven to the flower-peduncles. Homoplantaginin and luteolin 7-glucuronopyranoside are reported here for the first time from Aloe spp. To the best of our knowledge, this is the first report on the chemical composition and biological activity of those plant parts.

  13. AMP-activated kinase restricts Rift Valley fever virus infection by inhibiting fatty acid synthesis.

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    Theresa S Moser

    Full Text Available The cell intrinsic innate immune responses provide a first line of defense against viral infection, and often function by targeting cellular pathways usurped by the virus during infection. In particular, many viruses manipulate cellular lipids to form complex structures required for viral replication, many of which are dependent on de novo fatty acid synthesis. We found that the energy regulator AMPK, which potently inhibits fatty acid synthesis, restricts infection of the Bunyavirus, Rift Valley Fever Virus (RVFV, an important re-emerging arthropod-borne human pathogen for which there are no effective vaccines or therapeutics. We show restriction of RVFV both by AMPK and its upstream activator LKB1, indicating an antiviral role for this signaling pathway. Furthermore, we found that AMPK is activated during RVFV infection, leading to the phosphorylation and inhibition of acetyl-CoA carboxylase, the first rate-limiting enzyme in fatty acid synthesis. Activating AMPK pharmacologically both restricted infection and reduced lipid levels. This restriction could be bypassed by treatment with the fatty acid palmitate, demonstrating that AMPK restricts RVFV infection through its inhibition of fatty acid biosynthesis. Lastly, we found that this pathway plays a broad role in antiviral defense since additional viruses from disparate families were also restricted by AMPK and LKB1. Therefore, AMPK is an important component of the cell intrinsic immune response that restricts infection through a novel mechanism involving the inhibition of fatty acid metabolism.

  14. Antidiarrheal activity of extracts from Maytenus gonoclada and inhibition of Dengue virus by lupeol

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    FERNANDO C. SILVA

    Full Text Available ABSTRACT Diarrhea is an infectious disease caused by bacterial, virus, or protozoan, and dengue is caused by virus, included among the neglected diseases in several underdeveloped and developing countries, with an urgent demand for new drugs. Considering the antidiarrheal potential of species of Maytenus genus, a phytochemical investigation followed by antibacterial activity test with extracts of branches and heartwood and bark of roots from Maytenus gonoclada were conducted. Moreover, due the frequency of isolation of lupeol from Maytenus genus the antiviral activity against Dengue virus and cytotoxicity of lupeol and its complex with β-cyclodextrins were also tested. The results indicated the bioactivity of ethyl acetate extract from branches and ethanol extract from heartwood of roots of M. gonoclada against diarrheagenic bacteria. The lupeol showed potent activity against Dengue virus and low cytotoxicity in LLC-MK2 cells, but its complex with β-cyclodextrin was inactive. Considering the importance of novel and selective antiviral drug candidates the results seem to be promising.

  15. Human influenza A viruses are proteolytically activated and do not induce apoptosis in CACO-2 cells

    International Nuclear Information System (INIS)

    Zhirnov, Oleg; Klenk, Hans-Dieter

    2003-01-01

    Replication of human influenza A/H3N2 and A/H1N1 viruses was studied in human CACO-2 cells, a continuous line of intestinal epithelial differentiated cells. Hemagglutinin (HA) was cleaved in these cells by an endogenous protease. Thus, infectious virus was produced that underwent multiple cycle replication and plaque formation in the absence of trypsin added to the media. Cleavage of de novo-synthesized HA occurred at a late stage of the exocytic pathway as indicated by pulse-chase labeling and by experiments employing endoglycosidase H and brefeldin A treatment. However, surface-labeling experiments employing biotinylation suggested that there is no cleavage at the plasma membrane. Unlike HA of serotypes H5 and H7 cleaved at multibasic cleavage sites by furin, the HAs with monobasic cleavage sites analyzed here were not cleaved in CACO-2 cells in the presence of aprotinin, a natural inhibitor of trypsinlike proteases. Growing CACO-2 cells were able to cleave HA of incoming virus, although influenza virus activating protease was not detected in culture medium. These observations indicate that the activating enzyme of CACO-2 cells is a trypsinlike protease functioning in the trans-Golgi network and presumably endosomes. In support of this concept immune staining with antibodies specific to human and bovine trypsin revealed the presence of a trypsinlike protease in CACO-2 cells. Unlike MDCK and CV-1 cells undergoing rapid apoptosis after influenza virus infection, CACO-2 cells showed no apoptosis but displayed cytopathic effects with necrotic signs significantly later after infection. It follows from these data that, depending on the cell type, influenza virus may kill cells either by apoptosis or by necrosis

  16. Epstein-Barr virus immediate-early gene product trans-activates gene expression from the human immunodeficiency virus long terminal repeat

    International Nuclear Information System (INIS)

    Kenney, S.; Kamine, J.; Markovitz, D.; Fenrick, R.; Pagano, J.

    1988-01-01

    Acquired immunodeficiency syndrome patients are frequently coinfected with Epstein-Barr virus (EBV). In this report, the authors demonstrate that an EBV immediate-early gene product, BamHI MLF1, stimulates expression of the bacterial chloramphenicol acetyltransferase (CAT) gene linked to the human immunodeficiency virus (HIV) promoter. The HIV promoter sequences necessary for trans-activation by EBV do not include the tat-responsive sequences. In addition, in contrast to the other herpesvirus trans-activators previously studied, the EBV BamHI MLF1 gene product appears to function in part by a posttranscriptional mechanism, since it increases pHIV-CAT protein activity more than it increases HIV-CAT mRNA. This ability of an EBV gene product to activate HIV gene expression may have biologic consequences in persons coinfected with both viruses

  17. Anti-(human immunodeficiency virus) activity of polyoxotungstates and their inhibition of human immunodeficiency virus reverse transcriptase.

    Science.gov (United States)

    Moore, P S; Jones, C J; Mahmood, N; Evans, I G; Goff, M; Cooper, R; Hay, A J

    1995-01-01

    Heteropolyoxotungstates of the Keggin class containing different heteroatoms were tested for inhibition of two strains of human immunodeficiency virus 1 (HIV-1); they exhibited varying antiviral activity. Compounds containing boron were inactive, only one of those containing phosphorus showed selective anti-viral activity, whereas all silicon-containing compounds exhibited significant anti-viral activity in C8166 cells infected with the IIIB strain. Their effectiveness was some 10-fold higher in JM cells with selectivity indices of about 2000. The silicotungstates were effective inhibitors of HIV reverse transcriptase, showing greater inhibition with RNA/DNA template primers than with DNA/DNA template.primer. Kinetic analysis demonstrated that they inhibit the enzyme by different mechanisms, as, of the four compounds examined, two competed with template.primer and two competed with deoxynucleoside triphosphate. Inhibition of DNA polymerase activity by these compounds was compared using polymerases from different sources, including human; although not necessarily most specific for HIV-1 reverse transcriptase, they did not inhibit all DNA polymerases to a similar degree. PMID:7536411

  18. Characterisation of enzymatic activities of H5N1 influenza virus

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    Simson Tarigan

    2008-06-01

    Full Text Available One of the two glycoproteins projected from the surface of the influenza virus is identified as neuraminidase. This enzyme enables the virus to spread in the host, and therefore it plays vital roles in the viral pathogenicity. From the viewpoint of disease control, neuraminidase is used as the target for the development of anti-flu drugs, and for the development of diagnostic test to differentiate infected from vaccinated animals (DIVA. Since the roles of the enzyme are very important, information regarding the characteristics and the procedure to measure its activity, which is the purpose of this study, is essential. The optimum incubation time of the neuraminidase-substrate (fetuin reaction and the optimum pH of the buffer were determined. The stability of the enzyme against heating, supplementation or chelating of calcium ion, and b-propiolactone treatment were analysed. This study showed that neuraminidase from H5N1-influenza virus was, in regards to the characteristics investigated in this study, was comparable to that from Clostridium perfringens. The optimum incubation time for the viral and Clostridial neuraminidases were 60 and 30 minutes, respectively; whereas, the optimum pH for both neuraminidase was 6-7. At pH 8, both neuraminidase were inactive. Supplementation of calcium ion tended to increase activity but chelating of the cation did not have any observable effects. Treatment with 0.2% b-propiolactone for 6 hours reduced the activity, whereas heating at 60°C for 60 minutes abolished all activity. Since inactivation by b-propiolactone is partially only, neuraminidase assay could be performed safely in ordinary laboratories using b-propiolactone-treated-influenza virus, rather than the life virus. The thermolabile nature of the enzyme will complicate any attempt to purify the enzyme.

  19. Evaluation of antiviral activity of essential oil of Trachyspermum Ammi against Japanese encephalitis virus.

    Science.gov (United States)

    Roy, Soumen; Chaurvedi, Pratibha; Chowdhary, Abhay

    2015-01-01

    Japanese encephalitis is a leading form of viral encephalitis, prevalent mostly in South Eastern Asia caused by Japanese encephalitis virus (JEV). It is transmitted by the mosquitoes of the Culex sp. The disease affects children and results in 50% result in permanent neuropsychiatric disorder. There arises a need to develop a safe, affordable, and potent anti-viral agent against JEV. This study aimed to assess the antiviral activity of ajwain (Trachyspermum ammi: Umbellifereae) essential oil against JEV. Ajwain oil was extracted by distillation method and in vitro cytotoxicity assay was performed in vero cell line by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay method. JEV titer was determined by plaque assay and in vitro antiviral activity of ajwain oil was quantified by the plaque reduction neutralization test (PRNT). Cytotoxic concentration of the oil was found to be 1 mg/ml by MTT assay. The titer of the virus pool was found to be 50× 10(7) PFU/ml. we observed 80% and 40% virus inhibition in 0.5mg/ml of ajwain oil by PRNT method in preexposure treatment and postexposure treatment (antiviral activity), respectively. Our data indicate ajwain oil has potential in vitro antiviral activity against JEV. Further, the active biomolecule will be purified and evaluated for anti-JEV activity and also to scale up for in vivo trial to evaluate the efficacy of ajwain oil in future.

  20. MALT1 Controls Attenuated Rabies Virus by Inducing Early Inflammation and T Cell Activation in the Brain

    Science.gov (United States)

    2018-01-01

    ABSTRACT MALT1 is involved in the activation of immune responses, as well as in the proliferation and survival of certain cancer cells. MALT1 acts as a scaffold protein for NF-κB signaling and a cysteine protease that cleaves substrates, further promoting the expression of immunoregulatory genes. Deregulated MALT1 activity has been associated with autoimmunity and cancer, implicating MALT1 as a new therapeutic target. Although MALT1 deficiency has been shown to protect against experimental autoimmune encephalomyelitis, nothing is known about the impact of MALT1 on virus infection in the central nervous system. Here, we studied infection with an attenuated rabies virus, Evelyn-Rotnycki-Abelseth (ERA) virus, and observed increased susceptibility with ERA virus in MALT1−/− mice. Indeed, after intranasal infection with ERA virus, wild-type mice developed mild transient clinical signs with recovery at 35 days postinoculation (dpi). Interestingly, MALT1−/− mice developed severe disease requiring euthanasia at around 17 dpi. A decreased induction of inflammatory gene expression and cell infiltration and activation was observed in MALT1−/− mice at 10 dpi compared to MALT1+/+ infected mice. At 17 dpi, however, the level of inflammatory cell activation was comparable to that observed in MALT1+/+ mice. Moreover, MALT1−/− mice failed to produce virus-neutralizing antibodies. Similar results were obtained with specific inactivation of MALT1 in T cells. Finally, treatment of wild-type mice with mepazine, a MALT1 protease inhibitor, also led to mortality upon ERA virus infection. These data emphasize the importance of early inflammation and activation of T cells through MALT1 for controlling the virulence of an attenuated rabies virus in the brain. IMPORTANCE Rabies virus is a neurotropic virus which can infect any mammal. Annually, 59,000 people die from rabies. Effective therapy is lacking and hampered by gaps in the understanding of virus pathogenicity. MALT1

  1. MALT1 Controls Attenuated Rabies Virus by Inducing Early Inflammation and T Cell Activation in the Brain.

    Science.gov (United States)

    Kip, E; Staal, J; Verstrepen, L; Tima, H G; Terryn, S; Romano, M; Lemeire, K; Suin, V; Hamouda, A; Kalai, M; Beyaert, R; Van Gucht, S

    2018-04-15

    MALT1 is involved in the activation of immune responses, as well as in the proliferation and survival of certain cancer cells. MALT1 acts as a scaffold protein for NF-κB signaling and a cysteine protease that cleaves substrates, further promoting the expression of immunoregulatory genes. Deregulated MALT1 activity has been associated with autoimmunity and cancer, implicating MALT1 as a new therapeutic target. Although MALT1 deficiency has been shown to protect against experimental autoimmune encephalomyelitis, nothing is known about the impact of MALT1 on virus infection in the central nervous system. Here, we studied infection with an attenuated rabies virus, Evelyn-Rotnycki-Abelseth (ERA) virus, and observed increased susceptibility with ERA virus in MALT1 -/- mice. Indeed, after intranasal infection with ERA virus, wild-type mice developed mild transient clinical signs with recovery at 35 days postinoculation (dpi). Interestingly, MALT1 -/- mice developed severe disease requiring euthanasia at around 17 dpi. A decreased induction of inflammatory gene expression and cell infiltration and activation was observed in MALT1 -/- mice at 10 dpi compared to MALT1 +/+ infected mice. At 17 dpi, however, the level of inflammatory cell activation was comparable to that observed in MALT1 +/+ mice. Moreover, MALT1 -/- mice failed to produce virus-neutralizing antibodies. Similar results were obtained with specific inactivation of MALT1 in T cells. Finally, treatment of wild-type mice with mepazine, a MALT1 protease inhibitor, also led to mortality upon ERA virus infection. These data emphasize the importance of early inflammation and activation of T cells through MALT1 for controlling the virulence of an attenuated rabies virus in the brain. IMPORTANCE Rabies virus is a neurotropic virus which can infect any mammal. Annually, 59,000 people die from rabies. Effective therapy is lacking and hampered by gaps in the understanding of virus pathogenicity. MALT1 is an intracellular

  2. Comparative Safety and Efficacy Profile of a Novel Oil in Water Vaccine Adjuvant Comprising Vitamins A and E and a Catechin in Protective Anti-Influenza Immunity.

    Science.gov (United States)

    Patel, Sapna; Faraj, Yasser; Duso, Debra K; Reiley, William W; Karlsson, Erik A; Schultz-Cherry, Stacey; Vajdy, Michael

    2017-05-21

    Non-replicating vaccines, such as those based on recombinant proteins, require adjuvants and delivery systems, which have thus far depended on mimicking pathogen danger signals and strong pro-inflammatory responses. In search of a safer and more efficacious alternative, we tested whether vaccinations with influenza recombinant hemagglutinin (HA) mixed with a novel vegetable oil in water emulsion adjuvant (Natural Immune-enhancing Delivery System, NIDS), based on the immune-enhancing synergy of vitamins A and E and a catechin, could protect against intra-nasal challenge with live influenza virus. Vaccinations of inbred Brag Albino strain c (BALB/c) mice, with HA mixed with NIDS compared to other adjuvants, i.e., a squalene oil in water emulsion (Sq. oil), and the Toll Like Receptor 3 (TLR3) agonist Poly (I:C), induced significantly lower select innate pro-inflammatory responses in serum, but induced significantly higher adaptive antibody and splenic T Helper 1 (TH1) or TH2, but not TH17, responses. Vaccinations with NIDS protected against infection, as measured by clinical scores, lung viral loads, and serum hemagglutination inhibition titers. The NIDS exhibited a strong dose sparing effect and the adjuvant action of NIDS was intact in the outbred CD1 mice. Importantly, vaccinations with the Sq. oil, but not NIDS, induced a significantly higher Serum Amyloid P component, an acute phase reactant secreted by hepatocytes, and total serum IgE. Thus, the NIDS may be used as a clinically safer and more efficacious vaccine adjuvant against influenza, and potentially other infectious diseases.

  3. Comparative Safety and Efficacy Profile of a Novel Oil in Water Vaccine Adjuvant Comprising Vitamins A and E and a Catechin in Protective Anti-Influenza Immunity

    Directory of Open Access Journals (Sweden)

    Sapna Patel

    2017-05-01

    Full Text Available Non-replicating vaccines, such as those based on recombinant proteins, require adjuvants and delivery systems, which have thus far depended on mimicking pathogen danger signals and strong pro-inflammatory responses. In search of a safer and more efficacious alternative, we tested whether vaccinations with influenza recombinant hemagglutinin (HA mixed with a novel vegetable oil in water emulsion adjuvant (Natural Immune-enhancing Delivery System, NIDS, based on the immune-enhancing synergy of vitamins A and E and a catechin, could protect against intra-nasal challenge with live influenza virus. Vaccinations of inbred Brag Albino strain c (BALB/c mice, with HA mixed with NIDS compared to other adjuvants, i.e., a squalene oil in water emulsion (Sq. oil, and the Toll Like Receptor 3 (TLR3 agonist Poly (I:C, induced significantly lower select innate pro-inflammatory responses in serum, but induced significantly higher adaptive antibody and splenic T Helper 1 (TH1 or TH2, but not TH17, responses. Vaccinations with NIDS protected against infection, as measured by clinical scores, lung viral loads, and serum hemagglutination inhibition titers. The NIDS exhibited a strong dose sparing effect and the adjuvant action of NIDS was intact in the outbred CD1 mice. Importantly, vaccinations with the Sq. oil, but not NIDS, induced a significantly higher Serum Amyloid P component, an acute phase reactant secreted by hepatocytes, and total serum IgE. Thus, the NIDS may be used as a clinically safer and more efficacious vaccine adjuvant against influenza, and potentially other infectious diseases.

  4. Human immunodeficiency virus-induced pathology favored by cellular transmission and activation

    International Nuclear Information System (INIS)

    Lewis, D.E.; Yoffe, B.; Bosworth, C.G.; Hollinger, F.B.; Rich, R.R.

    1988-01-01

    Epidemiological data suggest that transmission of human immunodeficiency virus (HIV) occurs primarily by transference of virally infected cells. However, the efficiency of lytic productive infection induced by HIV after transmission of cell-associated virus vs. free virus is difficult to assess. The present studies compare the extent of depletion of CD4+ (helper/inducer) T cells after mixing uninfected cells with either free HIV or irradiated HIV-infected allogeneic or autologous cells in vitro. Rapid CD4+ cellular depletion occurred only in cultures containing allogeneic infected cells or after addition of a nonspecific T cell activation signal to cultures with autologous infected cells. These in vitro observations strongly support the epidemiological implication that interactions between infected and uninfected cells are the most efficient means of transmission and HIV-induced cytopathology in vivo. They also provide direct support for the concept that immunological stimulation by foreign cells infected with HIV dramatically increases the likelihood of transmission. These in vitro observations suggest a model for the acquisition of HIV in vivo and the role of cellular activation in dissemination of the virus to uninfected cells in an infected individual

  5. Mx Is Not Responsible for the Antiviral Activity of Interferon-α against Japanese Encephalitis Virus

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    Jing Zhou

    2017-01-01

    Full Text Available Mx proteins are interferon (IFN-induced dynamin-like GTPases that are present in all vertebrates and inhibit the replication of myriad viruses. However, the role Mx proteins play in IFN-mediated suppression of Japanese encephalitis virus (JEV infection is unknown. In this study, we set out to investigate the effects of Mx1 and Mx2 expression on the interferon-α (IFNα restriction of JEV replication. To evaluate whether the inhibitory activity of IFNα on JEV is dependent on Mx1 or Mx2, we knocked down Mx1 or Mx2 with siRNA in IFNα-treated PK-15 cells and BHK-21 cells, then challenged them with JEV; the production of progeny virus was assessed by plaque assay, RT-qPCR, and Western blotting. Our results demonstrated that depletion of Mx1 or Mx2 did not affect JEV restriction imposed by IFNα, although these two proteins were knocked down 66% and 79%, respectively. Accordingly, expression of exogenous Mx1 or Mx2 did not change the inhibitory activity of IFNα to JEV. In addition, even though virus-induced membranes were damaged by Brefeldin A (BFA, overexpressing porcine Mx1 or Mx2 did not inhibit JEV proliferation. We found that BFA inhibited JEV replication, not maturation, suggesting that BFA could be developed into a novel antiviral reagent. Collectively, our findings demonstrate that IFNα inhibits JEV infection by Mx-independent pathways.

  6. Antiviral Activity of Crude Hydroethanolic Extract from Schinus terebinthifolia against Herpes simplex Virus Type 1.

    Science.gov (United States)

    Nocchi, Samara Requena; Companhoni, Mychelle Vianna Pereira; de Mello, João Carlos Palazzo; Dias Filho, Benedito Prado; Nakamura, Celso Vataru; Carollo, Carlos Alexandre; Silva, Denise Brentan; Ueda-Nakamura, Tânia

    2017-04-01

    Herpes simplex virus infections persist throughout the lifetime of the host and affect more than 80 % of the humans worldwide. The intensive use of available therapeutic drugs has led to undesirable effects, such as drug-resistant strains, prompting the search for new antiherpetic agents. Although diverse bioactivities have been identified in Schinus terebinthifolia , its antiviral activity has not attracted much attention. The present study evaluated the antiherpetic effects of a crude hydroethanolic extract from the stem bark of S. terebinthifolia against Herpes simplex virus type 1 in vitro and in vivo as well as its genotoxicity in bone marrow in mammals and established the chemical composition of the crude hydroethanolic extract based on liquid chromatography-diode array detector-mass spectrometry and MS/MS. The crude hydroethanolic extract inhibited all of the tested Herpes simplex virus type 1 strains in vitro and was effective in the attachment and penetration stages, and showed virucidal activity, which was confirmed by transmission electron microscopy. The micronucleus test showed that the crude hydroethanolic extract had no genotoxic effect at the concentrations tested. The crude hydroethanolic extract afforded protection against lesions that were caused by Herpes simplex virus type 1 in vivo . Liquid chromatography-diode array detector-mass spectrometry and MS/MS identified 25 substances, which are condensed tannins mainly produced by a B-type linkage and prodelphinidin and procyanidin units. Georg Thieme Verlag KG Stuttgart · New York.

  7. Toll-like receptor agonist augments virus-like particle-mediated protection from Ebola virus with transient immune activation.

    Directory of Open Access Journals (Sweden)

    Karen A O Martins

    Full Text Available Identifying safe and effective adjuvants is critical for the advanced development of protein-based vaccines. Pattern recognition receptor (PRR agonists are increasingly being explored as potential adjuvants, but there is concern that the efficacy of these molecules may be dependent on potentially dangerous levels of non-specific immune activation. The filovirus virus-like particle (VLP vaccine protects mice, guinea pigs, and nonhuman primates from viral challenge. In this study, we explored the impact of a stabilized dsRNA mimic, polyICLC, on VLP vaccination of C57BL/6 mice and Hartley guinea pigs. We show that at dose levels as low as 100 ng, the adjuvant increased the efficacy of the vaccine in mice. Antigen-specific, polyfunctional CD4 and CD8 T cell responses and antibody responses increased significantly upon inclusion of adjuvant. To determine whether the efficacy of polyICLC correlated with systemic immune activation, we examined serum cytokine levels and cellular activation in the draining lymph node. PolyICLC administration was associated with increases in TNFα, IL6, MCP1, MIP1α, KC, and MIP1β levels in the periphery and with the activation of dendritic cells (DCs, NK cells, and B cells. However, this activation resolved within 24 to 72 hours at efficacious adjuvant dose levels. These studies are the first to examine the polyICLC-induced enhancement of antigen-specific immune responses in the context of non-specific immune activation, and they provide a framework from which to consider adjuvant dose levels.

  8. ANTIVIRAL ACTIVITY OF COPPER(IICHLORIDE DIHYDRATE AGAINST DENGUE VIRUS TYPE-2 IN VERO CELL

    Directory of Open Access Journals (Sweden)

    Teguh Hari Sucipto

    2017-04-01

    Full Text Available Infection of dengue virus (DENV was number of globally significant emerging pathogen. Antiviral dengue therapies ar importantly needed to control emerging dengue. Dengue virus (DENV is mosquito-borne arboviruses responsible for causing acute systemic diseases and grievous health conditions in humans. To date, there is no clinically approved dengue vaccine or antiviral for humans, even though there have been great efforts towards this end. Copper and copper compounds have more effective in inactivation viruses, likes an influenza virus and human immunodeficiency virus (HIV. Purpose in this project was investigated of Copper(IIchloride Dihydrate antiviral compound were further tested for inhibitory effect on the replication of DENV-2 in cell culture. DENV replication was measures by Enzyme linked Immunosorbent Assay (ELISA with selectivity index value (SI was determined as the ratio of cytotoxic concentration 50 (CC50 to inhibitory concentration 50 (IC50 for compound. The maximal inhibitory concentration (IC50 of Copper(IIchloride Dihydrate against dengue virus type-2 was 0.13 μg/ml. The cytotoxic concentration (CC50 of compound against Vero cell was 5.03 μg/ml. The SI values for Copper(IIchloride Dihydrate 38.69. Result of this study suggest that Copper(IIchloride Dihydrate demonstated significant anti-DENV-2 inhibitory activities and not toxic in the Vero cells. Copper mechanisms play an important role in the prevention of copper toxicity, exposure to excessive levels of copper can result in a number of adverse health effects, as a result increased reactive oxygen species and oxidative damage to lipid, DNA, and proteins have been observed in human cell culture models or clinical syndromes of severe copper deficiency and inhibition was attributed to released cupric ions which react with cysteine residues on the surface of the protease.

  9. Isolation and identification of compounds from Kalanchoe pinnata having human alphaherpesvirus and vaccinia virus antiviral activity.

    Science.gov (United States)

    Cryer, Matthew; Lane, Kyle; Greer, Mary; Cates, Rex; Burt, Scott; Andrus, Merritt; Zou, Jiping; Rogers, Paul; Hansen, Marc D H; Burgado, Jillybeth; Panayampalli, Subbian Satheshkumar; Day, Craig W; Smee, Donald F; Johnson, Brent F

    2017-12-01

    Kalanchoe pinnata (Lam.) Pers. (Crassulaceae) is a succulent plant that is known for its traditional antivirus and antibacterial usage. This work examines two compounds identified from the K. pinnata plant for their antivirus activity against human alphaherpesvirus (HHV) 1 and 2 and vaccinia virus (VACV). Compounds KPB-100 and KPB-200 were isolated using HPLC and were identified using NMR and MS. Both compounds were tested in plaque reduction assay of HHV-2 wild type (WT) and VACV. Both compounds were then tested in virus spread inhibition and virus yield reduction (VYR) assays of VACV. KPB-100 was further tested in viral cytopathic effect (CPE) inhibition assay of HHV-2 TK-mutant and VYR assay of HHV-1 WT. KPB-100 and KPB-200 inhibited HHV-2 at IC 50 values of 2.5 and 2.9 μg/mL, respectively, and VACV at IC 50 values of 3.1 and 7.4 μg/mL, respectively, in plaque reduction assays. In virus spread inhibition assay of VACV KPB-100 and KPB-200 yielded IC 50 values of 1.63 and 13.2 μg/mL, respectively, and KPB-100 showed a nearly 2-log reduction in virus in VYR assay of VACV at 20 μg/mL. Finally, KPB-100 inhibited HHV-2 TK- at an IC 50 value of 4.5 μg/mL in CPE inhibition assay and HHV-1 at an IC 90 of 3.0 μg/mL in VYR assay. Both compounds are promising targets for synthetic optimization and in vivo study. KPB-100 in particular showed strong inhibition of all viruses tested.

  10. RIG-I-like Receptor Triggering by Dengue Virus Drives Dendritic Cell Immune Activation and TH1 Differentiation

    NARCIS (Netherlands)

    Sprokholt, Joris K.; Kaptein, Tanja M.; van Hamme, John L.; Overmars, Ronald J.; Gringhuis, Sonja I.; Geijtenbeek, Teunis B. H.

    2017-01-01

    Dengue virus (DENV) causes 400 million infections annually and is one of several viruses that can cause viral hemorrhagic fever, which is characterized by uncontrolled immune activation resulting in high fever and internal bleeding. Although the underlying mechanisms are unknown, massive cytokine

  11. Poor outcomes of chronic active Epstein-Barr virus infection and hemophagocytic lymphohistiocytosis in non-Japanese adult patients

    NARCIS (Netherlands)

    Sonke, Gabe S.; Ludwig, Inge; van Oosten, Hannah; Baars, Joke W.; Meijer, Ellen; Kater, Arnon P.; de Jong, Daphne

    2008-01-01

    Chronic active Epstein-Barr virus infection manifests as a combination of persistent infectious mononucleosis-like symptoms and high viral load in apparently immunocompetent patients. It is closely related to Epstein-Barr virus associated hemophagocytic lymphohistiocytosis. These 2 abnormal

  12. Poor outcomes of chronic active Epstein-Barr virus infection and hemophagocytic lymphohistiocytosis in non-Japanese adult patients

    NARCIS (Netherlands)

    G.S. Sonke (Gabe); I. Ludwig (Inge); H. van Oosten (Hannah); J.W. Baars (Joke); E. Meijer (Ellen); A.P. Kater (Arnon); D. de Jong (Daphne)

    2008-01-01

    textabstractChronic active Epstein-Barr virus infection manifests as a combination of persistent infectious mononucleosis-like symptoms and high viral load in apparently immunocompetent patients. It is closely related to Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis. These 2

  13. Persistent abnormalities in lymphoid tissues of human immunodeficiency virus-infected patients successfully treated with highly active antiretroviral therapy

    NARCIS (Netherlands)

    Schacker, Timothy W.; Nguyen, Phuong L.; Martinez, Esteban; Reilly, Cavan; Gatell, Jose M.; Horban, Andrzej; Bakowska, Elzbieta; Berzins, Baiba; van Leeuwen, Remko; Wolinsky, Steven; Haase, Ashley T.; Murphy, Robert L.

    2002-01-01

    Effective highly active antiretroviral therapy (HAART) for human immunodeficiency virus type 1 is associated with virus suppression and immune reconstitution. However, in some patients, this reconstitution is partial or incomplete because CD4(+) cell counts do not increase significantly. This may be

  14. Innate Defense against Influenza A Virus: Activity of Human Neutrophil Defensins and Interactions of Defensins with Surfactant Protein D

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L.; White, Mitchell R.; Tecle, Tesfaldet

    2006-01-01

    Surfactant protein D (SP-D) plays important roles in innate host defense against influenza A virus (IAV) infection, in part by modifying interactions with neutrophils. Human neutrophil defensins (HNPs) inhibit infectivity of enveloped viruses, including IAV. Our goal in this study...... at sites of active inflammation....

  15. Antiviral activity of a Bacillus sp: P34 peptide against pathogenic viruses of domestic animals

    Directory of Open Access Journals (Sweden)

    Débora Scopel e Silva

    2014-09-01

    Full Text Available P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2, canine coronavirus (CCoV, canine distemper virus (CDV, canine parvovirus type 2 (CPV-2, equine arteritis virus (EAV, equine influenza virus (EIV, feline calicivirus (FCV and feline herpesvirus type 1 (FHV-1. The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 10(4.5 TCID50 to 10(2.75 TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections.

  16. Antibacterial and antifungal activities of new acylated derivatives of epigallocatechin gallate

    Directory of Open Access Journals (Sweden)

    Yoshimi eMatsumoto

    2012-02-01

    Full Text Available (--Epigallocatechin-3-O-gallate (EGCG has useful antiviral, antimicrobial, antitoxin, and antitumor properties. Previously, Mori, S. et al. (Bioorg Med Chem Lett 18:4249-4252, 2008 found that addition of long acyl chains (C16–18 to EGCG enhanced its anti-influenza virus activity up to 44-fold. The chemical stability of EGCG against oxidative degradation was also enhanced by acylation. We further evaluated the in vitro activity spectrum of the EGCG derivatives against a wide range of bacteria and fungi. A series of EGCG O-acyl derivatives were synthesized by lipase-catalyzed transesterification. These derivatives exhibited several-fold higher activities than EGCG, particularly against Gram-positive organisms. Antifungal activities of the derivatives were also 2 to 4-fold superior to those of EGCG. The activities of the EGCG derivatives against Gram-negative bacteria were not distinguishable from those of EGCG. Among the derivatives evaluated, MICs of dioctanoate, palmitate (C16, palmitoleate, and linolenate for 17 Staphylococcus aureus strains were 4–32 μg/ml, although MIC of EGCG for these 17 strains was >128 μg/ml. C16 demonstrated rapid bactericidal activity against MRSA at 25 μg/ml. The enhanced activity of C16 against S. aureus was supported by its increased membrane permeabilizing activity determined by increased SYTOX Green uptake. The EGCG derivatives were exported by the efflux pump AcrAB-TolC of Escherichia coli. The tolC deletion mutant exhibited higher sensitivity to C16 than to EGCG. Addition of long alkyl chains to EGCG significantly enhanced its activities against various bacteria and fungi, particularly against S. aureus including MRSA. C16 would be an alternative to antibiotics and disinfectants.

  17. C-terminal tyrosine residues modulate the fusion activity of the Hendra virus fusion protein.

    Science.gov (United States)

    Popa, Andreea; Pager, Cara Teresia; Dutch, Rebecca Ellis

    2011-02-15

    The paramyxovirus family includes important human pathogens such as measles, mumps, respiratory syncytial virus, and the recently emerged, highly pathogenic Hendra and Nipah viruses. The viral fusion (F) protein plays critical roles in infection, promoting both the virus-cell membrane fusion events needed for viral entry as well as cell-cell fusion events leading to syncytia formation. We describe the surprising finding that addition of the short epitope HA tag to the cytoplasmic tail (CT) of the Hendra virus F protein leads to a significant increase in the extent of cell-cell membrane fusion. This increase was not due to alterations in surface expression, cleavage state, or association with lipid microdomains. Addition of a Myc tag of similar length did not alter Hendra F protein fusion activity, indicating that the observed stimulation was not solely a result of lengthening the CT. Three tyrosine residues within the HA tag were critical for the increase in the extent of fusion, suggesting C-terminal tyrosines may modulate Hendra fusion activity. The effects of addition of the HA tag varied with other fusion proteins, as parainfluenza virus 5 F-HA showed a decreased level of surface expression and no stimulation of fusion. These results indicate that additions to the C-terminal end of the F protein CT can modulate protein function in a sequence specific manner, reinforcing the need for careful analysis of epitope-tagged glycoproteins. In addition, our results implicate C-terminal tyrosine residues in the modulation of the membrane fusion reaction promoted by these viral glycoproteins.

  18. Mutations in the PA Protein of Avian H5N1 Influenza Viruses Affect Polymerase Activity and Mouse Virulence.

    Science.gov (United States)

    Zhong, Gongxun; Le, Mai Quynh; Lopes, Tiago J S; Halfmann, Peter; Hatta, Masato; Fan, Shufang; Neumann, Gabriele; Kawaoka, Yoshihiro

    2018-02-15

    To study the influenza virus determinants of pathogenicity, we characterized two highly pathogenic avian H5N1 influenza viruses isolated in Vietnam in 2012 (A/duck/Vietnam/QT1480/2012 [QT1480]) and 2013 (A/duck/Vietnam/QT1728/2013 [QT1728]) and found that the activity of their polymerase complexes differed significantly, even though both viruses were highly pathogenic in mice. Further studies revealed that the PA-S343A/E347D (PA with the S-to-A change at position 343 and the E-to-D change at position 347) mutations reduced viral polymerase activity and mouse virulence when tested in the genetic background of QT1728 virus. In contrast, the PA-343S/347E mutations increased the polymerase activity of QT1480 and the virulence of a low-pathogenic H5N1 influenza virus. The PA-343S residue (which alone increased viral polymerase activity and mouse virulence significantly relative to viral replication complexes encoding PA-343A) is frequently found in H5N1 influenza viruses of several subclades; infection with a virus possessing this amino acid may pose an increased risk to humans. IMPORTANCE H5N1 influenza viruses cause severe infections in humans with a case fatality rate that exceeds 50%. The factors that determine the high virulence of these viruses in humans are not fully understood. Here, we identified two amino acid changes in the viral polymerase PA protein that affect the activity of the viral polymerase complex and virulence in mice. Infection with viruses possessing these amino acid changes may pose an increased risk to humans. Copyright © 2018 American Society for Microbiology.

  19. Virtual screening approach to identifying influenza virus neuraminidase inhibitors using molecular docking combined with machine-learning-based scoring function.

    Science.gov (United States)

    Zhang, Li; Ai, Hai-Xin; Li, Shi-Meng; Qi, Meng-Yuan; Zhao, Jian; Zhao, Qi; Liu, Hong-Sheng

    2017-10-10

    In recent years, an epidemic of the highly pathogenic avian influenza H7N9 virus has persisted in China, with a high mortality rate. To develop novel anti-influenza therapies, we have constructed a machine-learning-based scoring function (RF-NA-Score) for the effective virtual screening of lead compounds targeting the viral neuraminidase (NA) protein. RF-NA-Score is more accurate than RF-Score, with a root-mean-square error of 1.46, Pearson's correlation coefficient of 0.707, and Spearman's rank correlation coefficient of 0.707 in a 5-fold cross-validation study. The performance of RF-NA-Score in a docking-based virtual screening of NA inhibitors was evaluated with a dataset containing 281 NA inhibitors and 322 noninhibitors. Compared with other docking-rescoring virtual screening strategies, rescoring with RF-NA-Score significantly improved the efficiency of virtual screening, and a strategy that averaged the scores given by RF-NA-Score, based on the binding conformations predicted with AutoDock, AutoDock Vina, and LeDock, was shown to be the best strategy. This strategy was then applied to the virtual screening of NA inhibitors in the SPECS database. The 100 selected compounds were tested in an in vitro H7N9 NA inhibition assay, and two compounds with novel scaffolds showed moderate inhibitory activities. These results indicate that RF-NA-Score improves the efficiency of virtual screening for NA inhibitors, and can be used successfully to identify new NA inhibitor scaffolds. Scoring functions specific for other drug targets could also be established with the same method.

  20. Ebola Virus Disease Is Characterized by Poor Activation and Reduced Levels of Circulating CD16+ Monocytes.

    Science.gov (United States)

    Lüdtke, Anja; Ruibal, Paula; Becker-Ziaja, Beate; Rottstegge, Monika; Wozniak, David M; Cabeza-Cabrerizo, Mar; Thorenz, Anja; Weller, Romy; Kerber, Romy; Idoyaga, Juliana; Magassouba, N'Faly; Gabriel, Martin; Günther, Stephan; Oestereich, Lisa; Muñoz-Fontela, César

    2016-10-15

    A number of previous studies have identified antigen-presenting cells (APCs) as key targets of Ebola virus (EBOV), but the role of APCs in human Ebola virus disease (EVD) is not known. We have evaluated the phenotype and kinetics of monocytes, neutrophils, and dendritic cells (DCs) in peripheral blood of patients for whom EVD was diagnosed by the European Mobile Laboratory in Guinea. Acute EVD was characterized by reduced levels of circulating nonclassical CD16 + monocytes with a poor activation profile. In survivors, CD16 + monocytes were activated during recovery, coincident with viral clearance, suggesting an important role of this cell subset in EVD pathophysiology. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  1. Inhibitory effects of lapachol derivatives on epstein-barr virus activation.

    Science.gov (United States)

    Sacau, Elisa Pérez; Estévez-Braun, Ana; Ravelo, Angel G; Ferro, Esteban A; Tokuda, Harunkuni; Mukainaka, Teruo; Nishino, Hoyoku

    2003-02-20

    Sixteen derivatives (2-17) synthesized from the naphthoquinone lapachol (1), were tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), as a test for potential cancer chemopreventive agents. They exhibited a variety of inhibitory activities from very high to moderate, which allow us to suggest structure-activity relationships. Ten of these derivatives are reported for the first time, their structures being thoroughly determined by spectroscopic methods.

  2. Human immunodeficiency virus type 1 Tat upregulates interleukin-2 secretion in activated T cells.

    OpenAIRE

    Westendorp, M O; Li-Weber, M; Frank, R W; Krammer, P H

    1994-01-01

    Dysregulation of cytokines secreted by T cells may play an important role in the pathogenesis of AIDS. To investigate the effects of human immunodeficiency virus type 1 (HIV-1) Tat on interleukin-2 (IL-2) expression, we used IL-2 promoter-chloramphenicol acetyltransferase constructs and IL-2-secreting Jurkat T cells as a model system. Transient expression of HIV-1 Tat induced a five- to eightfold increase in IL-2 promoter activity in Jurkat T cells stimulated with phytohemagglutinin and phorb...

  3. Human immunodeficiency virus long terminal repeat responds to T-cell activation signals

    International Nuclear Information System (INIS)

    Tong-Starksen, S.E.; Luciw, P.A.; Peterlin, B.M.

    1987-01-01

    Human immunodeficiency virus (HIV), the causative agent of AIDS, infects and kills lymphoid cells bearing the CD4 antigen. In an infected cell, a number of cellular as well as HIV-encoded gene products determine the levels of viral gene expression and HIV replication. Efficient HIV replication occurs in activated T cells. Utilizing transient expression assays, the authors show that gene expression directed by the HIV long terminal repeat (LTR) increases in response to T-cell activation signals. The effects of T-cell activation and of the HIV-encoded trans-activator (TAT) are multiplicative. Analysis of mutations and deletions in the HIV LTR reveals that the region responding to T-cell activation signals is located at positions -105 to -80. These sequences are composed of two direct repeats, which are homologous to the core transcriptional enhancer elements in the simian virus 40 genome. The studies reveal that these elements function as the HIV enhancer. By acting directly on the HIV LTR, T-cell activation may play an important role in HIV gene expression and in the activation of latent HIV

  4. Inhibition of RNA recruitment and replication of an RNA virus by acridine derivatives with known anti-prion activities.

    Directory of Open Access Journals (Sweden)

    Zsuzsanna Sasvari

    Full Text Available BACKGROUND: Small molecule inhibitors of RNA virus replication are potent antiviral drugs and useful to dissect selected steps in the replication process. To identify antiviral compounds against Tomato bushy stunt virus (TBSV, a model positive stranded RNA virus, we tested acridine derivatives, such as chlorpromazine (CPZ and quinacrine (QC, which are active against prion-based diseases. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that CPZ and QC compounds inhibited TBSV RNA accumulation in plants and in protoplasts. In vitro assays revealed that the inhibitory effects of these compounds were manifested at different steps of TBSV replication. QC was shown to have an effect on multiple steps, including: (i inhibition of the selective binding of the p33 replication protein to the viral RNA template, which is required for recruitment of viral RNA for replication; (ii reduction of minus-strand synthesis by the tombusvirus replicase; and (iii inhibition of translation of the uncapped TBSV genomic RNA. In contrast, CPZ was shown to inhibit the in vitro assembly of the TBSV replicase, likely due to binding of CPZ to intracellular membranes, which are important for RNA virus replication. CONCLUSION/SIGNIFICANCE: Since we found that CPZ was also an effective inhibitor of other plant viruses, including Tobacco mosaic virus and Turnip crinkle virus, it seems likely that CPZ has a broad range of antiviral activity. Thus, these inhibitors constitute effective tools to study similarities in replication strategies of various RNA viruses.

  5. Inhibition of RNA Recruitment and Replication of an RNA Virus by Acridine Derivatives with Known Anti-Prion Activities

    Science.gov (United States)

    Sasvari, Zsuzsanna; Bach, Stéphane; Blondel, Marc; Nagy, Peter D.

    2009-01-01

    Background Small molecule inhibitors of RNA virus replication are potent antiviral drugs and useful to dissect selected steps in the replication process. To identify antiviral compounds against Tomato bushy stunt virus (TBSV), a model positive stranded RNA virus, we tested acridine derivatives, such as chlorpromazine (CPZ) and quinacrine (QC), which are active against prion-based diseases. Methodology/Principal Findings Here, we report that CPZ and QC compounds inhibited TBSV RNA accumulation in plants and in protoplasts. In vitro assays revealed that the inhibitory effects of these compounds were manifested at different steps of TBSV replication. QC was shown to have an effect on multiple steps, including: (i) inhibition of the selective binding of the p33 replication protein to the viral RNA template, which is required for recruitment of viral RNA for replication; (ii) reduction of minus-strand synthesis by the tombusvirus replicase; and (iii) inhibition of translation of the uncapped TBSV genomic RNA. In contrast, CPZ was shown to inhibit the in vitro assembly of the TBSV replicase, likely due to binding of CPZ to intracellular membranes, which are important for RNA virus replication. Conclusion/Significance Since we found that CPZ was also an effective inhibitor of other plant viruses, including Tobacco mosaic virus and Turnip crinkle virus, it seems likely that CPZ has a broad range of antiviral activity. Thus, these inhibitors constitute effective tools to study similarities in replication strategies of various RNA viruses. PMID:19823675

  6. Host Plants Indirectly Influence Plant Virus Transmission by Altering Gut Cysteine Protease Activity of Aphid Vectors.

    Science.gov (United States)

    Pinheiro, Patricia V; Ghanim, Murad; Alexander, Mariko; Rebelo, Ana Rita; Santos, Rogerio S; Orsburn, Benjamin C; Gray, Stewart; Cilia, Michelle

    2017-04-01

    The green peach aphid, Myzus persicae , is a vector of the Potato leafroll virus (PLRV, Luteoviridae), transmitted exclusively by aphids in a circulative manner. PLRV transmission efficiency was significantly reduced when a clonal lineage of M. persicae was reared on turnip as compared with the weed physalis, and this was a transient effect caused by a host-switch response. A trend of higher PLRV titer in physalis-reared aphids as compared with turnip-reared aphids was observed at 24 h and 72 h after virus acquisition. The major difference in the proteomes of these aphids was the up-regulation of predicted lysosomal enzymes, in particular the cysteine protease cathepsin B (cathB), in aphids reared on turnip. The aphid midgut is the site of PLRV acquisition, and cathB and PLRV localization were starkly different in midguts of the aphids reared on the two host plants. In viruliferous aphids that were reared on turnip, there was near complete colocalization of cathB and PLRV at the cell membranes, which was not observed in physalis-reared aphids. Chemical inhibition of cathB restored the ability of aphids reared on turnip to transmit PLRV in a dose-dependent manner, showing that the increased activity of cathB and other cysteine proteases at the cell membrane indirectly decreased virus transmission by aphids. Understanding how the host plant influences virus transmission by aphids is critical for growers to manage the spread of virus among field crops. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. In vitro and in vivo activity of ribavirin against Andes virus infection.

    Directory of Open Access Journals (Sweden)

    David Safronetz

    Full Text Available Pathogenic hantaviruses are a closely related group of rodent-borne viruses which are responsible for two distinct diseases in humans, hemorrhagic fever with renal syndrome and hantavirus pulmonary syndrome (HPS, otherwise known as hantavirus cardiopulmonary syndrome, HCPS. The antiviral effect of ribavirin against Old World hantaviruses, most notably Hantaan virus, is well documented; however, only a few studies have addressed its inhibitory effect on New World hantaviruses. In the present study, we demonstrate that ribavirin is highly active against Andes virus (ANDV, an important etiological agent of HPS, both in vitro and in vivo using a lethal hamster model of HPS. Treatment of ANDV infected Vero E6 cells with ribavirin resulted in dose-dependent reductions in viral RNA and protein as well as virus yields with a half maximal inhibitory concentration between 5 and 12.5 µg ml(-1. In hamsters, treatment with as little as 5 mg kg(-1 day(-1 was 100% effective at preventing lethal HPS disease when therapy was administered by intraperitoneal injection from day 1 through day 10 post-infection. Significant reductions were observed in ANDV RNA and antigen positive cells in lung and liver tissues. Ribavirin remained completely protective when administered by intraperitoneal injections up to three days post-infection. In addition, we show that daily oral ribavirin therapy initiated 1 day post-infection and continuing for ten days is also protective against lethal ANDV disease, even at doses of 5 mg kg(-1 day(-1. Our results suggest ribavirin treatment is beneficial for postexposure prophylaxis against HPS-causing hantaviruses and should be considered in scenarios where exposure to the virus is probable. The similarities between the results obtained in this study and those from previous clinical evaluations of ribavirin against HPS, further validate the hamster model of lethal HPS and demonstrate its usefulness in screening antiviral agents against

  8. Well-tolerated Spirulina extract inhibits influenza virus replication and reduces virus-induced mortality

    Science.gov (United States)

    Chen, Yi-Hsiang; Chang, Gi-Kung; Kuo, Shu-Ming; Huang, Sheng-Yu; Hu, I-Chen; Lo, Yu-Lun; Shih, Shin-Ru

    2016-01-01

    Influenza is one of the most common human respiratory diseases, and represents a serious public health concern. However, the high mutability of influenza viruses has hampered vaccine development, and resistant strains to existing anti-viral drugs have also emerged. Novel anti-influenza therapies are urgently needed, and in this study, we describe the anti-viral properties of a Spirulina (Arthrospira platensis) cold water extract. Anti-viral effects have previously been reported for extracts and specific substances derived from Spirulina, and here we show that this Spirulina cold water extract has low cellular toxicity, and is well-tolerated in animal models at one dose as high as 5,000 mg/kg, or 3,000 mg/kg/day for 14 successive days. Anti-flu efficacy studies revealed that the Spirulina extract inhibited viral plaque formation in a broad range of influenza viruses, including oseltamivir-resistant strains. Spirulina extract was found to act at an early stage of infection to reduce virus yields in cells and improve survival in influenza-infected mice, with inhibition of influenza hemagglutination identified as one of the mechanisms involved. Together, these results suggest that the cold water extract of Spirulina might serve as a safe and effective therapeutic agent to manage influenza outbreaks, and further clinical investigation may be warranted. PMID:27067133

  9. Well-tolerated Spirulina extract inhibits influenza virus replication and reduces virus-induced mortality.

    Science.gov (United States)

    Chen, Yi-Hsiang; Chang, Gi-Kung; Kuo, Shu-Ming; Huang, Sheng-Yu; Hu, I-Chen; Lo, Yu-Lun; Shih, Shin-Ru

    2016-04-12

    Influenza is one of the most common human respiratory diseases, and represents a serious public health concern. However, the high mutability of influenza viruses has hampered vaccine development, and resistant strains to existing anti-viral drugs have also emerged. Novel anti-influenza therapies are urgently needed, and in this study, we describe the anti-viral properties of a Spirulina (Arthrospira platensis) cold water extract. Anti-viral effects have previously been reported for extracts and specific substances derived from Spirulina, and here we show that this Spirulina cold water extract has low cellular toxicity, and is well-tolerated in animal models at one dose as high as 5,000 mg/kg, or 3,000 mg/kg/day for 14 successive days. Anti-flu efficacy studies revealed that the Spirulina extract inhibited viral plaque formation in a broad range of influenza viruses, including oseltamivir-resistant strains. Spirulina extract was found to act at an early stage of infection to reduce virus yields in cells and improve survival in influenza-infected mice, with inhibition of influenza hemagglutination identified as one of the mechanisms involved. Together, these results suggest that the cold water extract of Spirulina might serve as a safe and effective therapeutic agent to manage influenza outbreaks, and further clinical investigation may be warranted.

  10. Inhibition of influenza A virus (H1N1 fusion by benzenesulfonamide derivatives targeting viral hemagglutinin.

    Directory of Open Access Journals (Sweden)

    Lei Zhu

    Full Text Available Hemagglutinin (HA of the influenza virus plays a crucial role in the early stage of the viral life cycle by binding to sialic acid on the surface of host epithelial cells and mediating fusion between virus envelope and endosome membrane for the release of viral genomes into the cytoplasm. To initiate virus fusion, endosome pH is lowered by acidification causing an irreversible conformational change of HA, which in turn results in a fusogenic HA. In this study, we describe characterization of an HA inhibitor of influenza H1N1 viruses, RO5464466. One-cycle time course study in MDCK cells showed that this compound acted at an early step of influenza virus replication. Results from HA-mediated hemolysis of chicken red blood cells and trypsin sensitivity assay of isolated HA clearly showed that RO5464466 targeted HA. In cell-based assays involving multiple rounds of virus infection and replication, RO5464466 inhibited an established influenza infection. The overall production of progeny viruses, as a result of the compound's inhibitory effect on fusion, was dramatically reduced by 8 log units when compared with a negative control. Furthermore, RO5487624, a close analogue of RO5464466, with pharmacokinetic properties suitable for in vivo efficacy studies displayed a protective effect on mice that were lethally challenged with influenza H1N1 virus. These results might benefit further characterization and development of novel anti-influenza agents by targeting viral hemagglutinin.

  11. P1-Substituted Symmetry-Based Human Immunodeficiency Virus Protease Inhibitors with Potent Antiviral Activity against Drug-Resistant Viruses

    Energy Technology Data Exchange (ETDEWEB)

    DeGoey, David A.; Grampovnik, David J.; Chen, Hui-Ju; Flosi, William J.; Klein, Larry L.; Dekhtyar, Tatyana; Stoll, Vincent; Mamo, Mulugeta; Molla, Akhteruzzaman; Kempf, Dale J. (Abbott)

    2013-03-07

    Because there is currently no cure for HIV infection, patients must remain on long-term drug therapy, leading to concerns over potential drug side effects and the emergence of drug resistance. For this reason, new and safe antiretroviral agents with improved potency against drug-resistant strains of HIV are needed. A series of HIV protease inhibitors (PIs) with potent activity against both wild-type (WT) virus and drug-resistant strains of HIV was designed and synthesized. The incorporation of substituents with hydrogen bond donor and acceptor groups at the P1 position of our symmetry-based inhibitor series resulted in significant potency improvements against the resistant mutants. By this approach, several compounds, such as 13, 24, and 29, were identified that demonstrated similar or improved potencies compared to 1 against highly mutated strains of HIV derived from patients who previously failed HIV PI therapy. Overall, compound 13 demonstrated the best balance of potency against drug resistant strains of HIV and oral bioavailability in pharmacokinetic studies. X-ray analysis of an HIV PI with an improved resistance profile bound to WT HIV protease is also reported.

  12. Persistent virus infection despite chronic cytotoxic T-lymphocyte activation in gamma interferon-deficient mice infected with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Bartholdy, C; Christensen, Jan Pravsgaard; Wodarz, D

    2000-01-01

    in wild-type mice. These findings indicate that in the absence of IFN-gamma, CTLs cannot clear the infection and are kept permanently activated by the continuous presence of live virus, resulting in a delicate new balance between viral load and immunity. This interpretation of our findings is supported...

  13. Matrix Metalloproteinase Activity in Infections by an Encephalitic Virus, Mouse Adenovirus Type 1

    Science.gov (United States)

    Ashley, Shanna L.; Pretto, Carla D.; Stier, Matthew T.; Kadiyala, Padma; Castro-Jorge, Luiza; Hsu, Tien-Huei; Doherty, Robert; Carnahan, Kelly E.; Castro, Maria G.; Lowenstein, Pedro R.

    2017-01-01

    ABSTRACT Mouse adenovirus type 1 (MAV-1) infection causes encephalitis in susceptible strains of mice and alters the permeability of infected brains to small molecules, which indicates disruption of the blood-brain barrier (BBB). Under pathological conditions, matrix metalloproteinases (MMPs) can disrupt the BBB through their proteolytic activity on basement membrane and tight junction proteins. We examined whether MAV-1 infection alters MMP activity in vivo and in vitro. Infected MAV-1-susceptible SJL mice had higher MMP2 and MMP9 activity in brains, measured by gelatin zymography, than mock-infected mice. Infected MAV-1-resistant BALB/c mice had MMP activity levels equivalent to those in mock infection. Primary SJL mouse brain endothelial cells (a target of MAV-1 in vivo) infected ex vivo with MAV-1 had no difference in activities of secreted MMP2 and MMP9 from mock cells. We show for the first time that astrocytes and microglia are also infected in vivo by MAV-1. Infected mixed primary cultures of astrocytes and microglia had higher levels of MMP2 and MMP9 activity than mock-infected cells. These results indicate that increased MMP activity in the brains of MAV-1-infected susceptible mice may be due to MMP activity produced by endothelial cells, astrocytes, and microglia, which in turn may contribute to BBB disruption and encephalitis in susceptible mice. IMPORTANCE RNA and DNA viruses can cause encephalitis; in some cases, this is accompanied by MMP-mediated disruption of the BBB. Activated MMPs degrade extracellular matrix and cleave tight-junction proteins and cytokines, modulating their functions. MAV-1 infection of susceptible mice is a tractable small-animal model for encephalitis, and the virus causes disruption of the BBB. We showed that MAV-1 infection increases enzymatic activity of two key MMPs known to be secreted and activated in neuroinflammation, MMP2 and MMP9, in brains of susceptible mice. MAV-1 infects endothelial cells, astrocytes, and

  14. Antiviral activity of natural and semisynthetic polysaccharides on the early steps of rubella virus infection.

    Science.gov (United States)

    Mastromarino, P; Petruzziello, R; Macchia, S; Rieti, S; Nicoletti, R; Orsi, N

    1997-03-01

    The natural and semisynthetic carbohydrates scleroglucan, locust bean gum, tamarind gum (glyloid) and its three sulphate derivatives (GP4311, GP4327 and GP4324), glycogen and its two sulphate derivatives (GP4427 and GP4435), alginic acid and dextran sulphate, were investigated for their inhibitory effect on rubella virus (RV) infection of Vero cells. The neutral polymer scleroglucan and two highly negatively charged compounds, glyloid sulphate 4324 and dextran sulphate, had the highest inhibitory effect on RV antigen synthesis. The antiviral properties of active molecules appears to be dependent on the shape of the macromolecule and/or on the electric charge, while saccharide units play a minor role. The results indicated that polysaccharides blocked a step in virus replication subsequent to virus attachment, such as internalization and/or uncoating. Confirmation that the inhibitory activity of the compounds was directed at the early steps of RV multiplication, was that none of the polysaccharides had any effect on infection initiated by transfection of cells with RVRNA.

  15. Stochastic acidification, activation of hemagglutinin and escape of influenza viruses from an endosome

    Science.gov (United States)

    Lagache, Thibault; Sieben, Christian; Meyer, Tim; Herrmann, Andreas; Holcman, David

    2017-06-01

    Influenza viruses enter the cell inside an endosome. During the endosomal journey, acidification triggers a conformational change of the virus spike protein hemagglutinin (HA) that results in escape of the viral genome from the endosome into the cytoplasm. It is still unclear how the interplay between acidification and HA conformation changes affects the kinetics of the viral endosomal escape. We develop here a stochastic model to estimate the change of conformation of HAs inside the endosome nanodomain. Using a Markov process, we model the arrival of protons to HA binding sites and compute the kinetics of their accumulation. We compute the Mean First Passage Time (MFPT) of the number of HA bound sites to a threshold, which is used to estimate the HA activation rate for a given pH concentration. The present analysis reveals that HA proton binding sites possess a high chemical barrier, ensuring a stability of the spike protein at sub-acidic pH. We predict that activating more than 3 adjacent HAs is necessary to trigger endosomal fusion and this configuration prevents premature release of viruses from early endosomes

  16. PKR Activation Favors Infectious Pancreatic Necrosis Virus Replication in Infected Cells

    Directory of Open Access Journals (Sweden)

    Amr A.A. Gamil

    2016-06-01

    Full Text Available The double-stranded RNA-activated protein kinase R (PKR is a Type I interferon (IFN stimulated gene that has important biological and immunological functions. In viral infections, in general, PKR inhibits or promotes viral replication, but PKR-IPNV interaction has not been previously studied. We investigated the involvement of PKR during infectious pancreatic necrosis virus (IPNV infection using a custom-made rabbit antiserum and the PKR inhibitor C16. Reactivity of the antiserum to PKR in CHSE-214 cells was confirmed after IFNα treatment giving an increased protein level. IPNV infection alone did not give increased PKR levels by Western blot, while pre-treatment with PKR inhibitor before IPNV infection gave decreased eukaryotic initiation factor 2-alpha (eIF2α phosphorylation. This suggests that PKR, despite not being upregulated, is involved in eIF2α phosphorylation during IPNV infection. PKR inhibitor pre-treatment resulted in decreased virus titers, extra- and intracellularly, concomitant with reduction of cells with compromised membranes in IPNV-permissive cell lines. These findings suggest that IPNV uses PKR activation to promote virus replication in infected cells.

  17. Activation of peripheral blood mononuclear cells by dengue virus infection depotentiates balapiravir.

    Science.gov (United States)

    Chen, Yen-Liang; Abdul Ghafar, Nahdiyah; Karuna, Ratna; Fu, Yilong; Lim, Siew Pheng; Schul, Wouter; Gu, Feng; Herve, Maxime; Yokohama, Fumiaki; Wang, Gang; Cerny, Daniela; Fink, Katja; Blasco, Francesca; Shi, Pei-Yong

    2014-02-01

    In a recent clinical trial, balapiravir, a prodrug of a cytidine analog (R1479), failed to achieve efficacy (reducing viremia after treatment) in dengue patients, although the plasma trough concentration of R1479 remained above the 50% effective concentration (EC(50)). Here, we report experimental evidence to explain the discrepancy between the in vitro and in vivo results and its implication for drug development. R1479 lost its potency by 125-fold when balapiravir was used to treat primary human peripheral blood mononuclear cells (PBMCs; one of the major cells targeted for viral replication) that were preinfected with dengue virus. The elevated EC(50) was greater than the plasma trough concentration of R1479 observed in dengue patients treated with balapiravir and could possibly explain the efficacy failure. Mechanistically, dengue virus infection triggered PBMCs to generate cytokines, which decreased their efficiency of conversion of R1479 to its triphosphate form (the active antiviral ingredient), resulting in decreased antiviral potency. In contrast to the cytidine-based compound R1479, the potency of an adenosine-based inhibitor of dengue virus (NITD008) was much less affected. Taken together, our results demonstrate that viral infection in patients before treatment could significantly affect the conversion of the prodrug to its active form; such an effect should be calculated when estimating the dose efficacious for humans.

  18. Anti-dengue virus serotype 2 activity and mode of action of a novel peptide.

    Science.gov (United States)

    Chew, M-F; Tham, H-W; Rajik, M; Sharifah, S H

    2015-10-01

    To identify a novel antiviral peptide against dengue virus serotype 2 (DENV-2) by screening a phage display peptide library and to evaluate its in vitro antiviral activity and mode of action. A phage display peptide library was biopanned against purified DENV-2 and resulted in the identification and selection of a peptide (peptide gg-ww) for further investigation. ELISA was performed, and peptide gg-ww was shown to possess the highest binding affinity against DENV-2. Thus, peptide gg-ww was synthesized for cytotoxicity and antiviral assays. Virus plaque reduction assay, real-time PCR and immunofluorescence assay were used to investigate the inhibitory effect of peptide gg-ww on DENV-2 infection in Vero cells. Three different assays (pre-, simultaneous and post-treatments assays) were performed to investigate the peptide's mode of action. Results indicated that peptide gg-ww possessed strong antiviral activity with a ~96% inhibition rate, which was achieved at 250 μmol l(-1) . Viral replication was inhibited during a simultaneous treatment assay, indicating that the entry of the virus was impeded by this peptide. Peptide gg-ww displayed antiviral action against DENV-2 by targeting an early stage of viral replication (i.e. during viral entry). Peptide gg-ww may represent a new therapeutic candidate for the treatment of DENV infections and is a potential candidate to be developed as a peptide drug. © 2015 The Society for Applied Microbiology.

  19. Assays for Hepatitis B Virus DNA-and RNA-Dependent DNA Polymerase Activities.

    Science.gov (United States)

    Shaw, T; Locarnini, S A

    2000-01-01

    Genomes of the hepatitis B viruses (HBVs) consist of approx 3.2 kb of partly double-stranded DNA containing three or four overlapping open reading frames, the largest of which encodes the viral polymerase (Pol) protein. After entry into the cell and uncoating, the viral genome is transported to the nucleus where it is converted into a covalently closed circular (CCC) or supercoiled molecule by cellular repair mechanisms. The viral CCC DNA is transcribed, presumably by host cell RNA polymerase II, into unspliced, capped polyadenylated mRNA species from which viral proteins are transcribed. In addition, terminally redundant 3.5-kb RNA transcripts, which function as pregenomes, are produced and exported to the cytoplasm where they are packaged into viral core particles in which reverse transcription, pregenome degradation, and duplication occurs, reproducing the partly double-stranded HBV genome (for recent review, see ref. 1). Besides its essential role in HBV genome replication, HBV Pol is also involved in virus assembly, and because hepadnaviruses do not encode enzymes functionally equivalent to deoxynucleoside kinases (2), functions associated with HBV Pol are probably the only virus-specific targets for antiviral activity of nucleoside analogs. In vitro assays for inhibition of HBV Pol functions by deoxynucleoside triphosphate (dNTP) analogs are useful indicators but, because of restrictions imposed by hepatocyte enzymology, provide no guarantee of potential anti-HBV activity of the parent (deoxy)nucleoside analogs in intact cells (2).

  20. Herpes Simplex Virus Type 1 Infection of Activated Cytotoxic T Cells

    Science.gov (United States)

    Raftery, Martin J.; Behrens, Christian K.; Müller, Anke; Krammer, Peter H.; Walczak, Henning; Schönrich, Günther

    1999-01-01

    Herpes simplex virus type 1 (HSV1), a large DNA-containing virus, is endemic in all human populations investigated. After infection of mucocutaneous surfaces, HSV1 establishes a latent infection in nerve cells. Recently, it was demonstrated that HSV1 can also infect activated T lymphocytes. However, the consequences of T cell infection for viral pathogenesis and immunity are unknown. We have observed that in contrast to the situation in human fibroblasts, in human T cell lines antigen presentation by major histocompatibility complex class I molecules is not blocked after HSV1 infection. Moreover, HSV1 infection of T cells results in rapid elimination of antiviral T cells by fratricide. To dissect the underlying molecular events, we used a transgenic mouse model of HSV1 infection to demonstrate that CD95 (Apo-1, Fas)-triggered apoptosis is essential for HSV1-induced fratricide, whereas tumor necrosis factor (TNF) also contributes to this phenomenon but to a lesser extent. By contrast, neither TRAIL (TNF-related apoptosis-inducing ligand) nor perforin were involved. Finally, we defined two mechanisms associated with HSV1-associated fratricide of antiviral T cells: (a) T cell receptor–mediated upregulation of CD95 ligand and (b) a viral “competence-to-die” signal that renders activated T lymphocytes susceptible to CD95 signaling. We propose that induction of fratricide is an important immune evasion mechanism of HSV1, helping the virus to persist in the host organism throughout its lifetime. PMID:10523608

  1. Sphingolipids activate membrane fusion of Semliki Forest virus in a stereospecific manner

    DEFF Research Database (Denmark)

    Moesby, Lise; Corver, J; Erukulla, R K

    1995-01-01

    on degradation of the viral capsid protein by trypsin encapsulated in the target liposomes. Fusion mediated by D-erythro-ceramide was not affected by the additional presence in the target liposomes of ceramide stereoisomers incapable of fusion activation. Binding of the virus to the liposomes, as assessed...... by flotation on sucrose density gradients, was not dependent on the presence of fusion-competent or fusion-incompetent sphingolipids in the liposomes. The results of this study support the notion that a stereospecific interaction of the viral fusion protein with D-erythro sphingolipids in the target membrane......The alphavirus Semliki Forest virus (SFV) enters cells through receptor-mediated endocytosis. Subsequently, triggered by the acid pH in endosomes, the viral envelope fuses with the endosomal membrane. Membrane fusion of SFV has been shown previously to be dependent on the presence of cholesterol...

  2. [A case with chronic active EB virus infection accompanied with pulmonary candidiasis].

    Science.gov (United States)

    Karino, T; Nakamura, J; Fujita, K; Kobashi, Y; Yano, T; Okimoto, N; Soejima, R

    1998-12-01

    A 44-year-old woman with a history of intermittent fever for several years was admitted because of burn on her leg. On admission, she had hepatosplenomegaly and fever. Antibiotic therapy was started for bacterial infection of the burn. She lost her appetite and IVH was started. During the treatment, high fever appeared and chest X-ray films showed multiple nodular infiltrates throughout both lung fields. Candida albicans was isolated from IVH catheter culture and pulmonary candidiasis was suspected. Her fever and lung involvements were successfully treated with fluconazole. During the course, serum anti-EB-VCA-IgG antibody persisted at a high titer and anti-EBNA antibody remained negative. EB virus DNA was detected in the peripheral blood and bone marrow. Thus, she was diagnosed as chronic active EB virus infection.

  3. Chemical components of Ardisia splendens leaves and their activity against coxsackie A16 viruses.

    Science.gov (United States)

    Van Nguyen, Thi Hong; Vien, Trinh Anh; Nhiem, Nguyen Xuan; Van Kiem, Phan; Van Minh, Chau; Long, Pham Quoc; Anh, Luu Tuan; Cuong, Nguyen Manh; Song, Jae-Hyoung; Ko, Hyun-Jeong; Kim, Nanyoung; Park, Seon Ju; Kim, Seung Hyun

    2014-05-01

    Using a combination of chromatographic methods, one new flavonol glycoside, myricetin 3,7-di-O-alpha-L-rhamnopyranoside (1), and nine known compounds myricitrin (2), quercetin 3,7-di-O-alpha-L-rhamnopyranoside (3), quercitrin (4), desmanthin-l (5), myricetin 3-O-(3"-O-galloyl)-alpha-L-rhamnopyranoside (6), (+)-catechin (7), benzyl O-1-D-glucopyranoside (8), 2-phenylethyl O-beta-D-glucopyranoside (9), and corilagin (10) were isolated from the leaves of Ardisia splendens Pit. Based on an in vitro test against Coxsackie viruses A16 by SRB assay, only compounds 2, 5, and 10 exhibited activity against Coxsackie viruses A16 with IC50 values of 40.1, 32.2, and 30.5 microM, respectively. This result suggested that compounds 2, 5, and 10 might be potential agents for treating hand, foot and mouth diseases.

  4. High content image-based screening of a protease inhibitor library reveals compounds broadly active against Rift Valley fever virus and other highly pathogenic RNA viruses.

    Science.gov (United States)

    Mudhasani, Rajini; Kota, Krishna P; Retterer, Cary; Tran, Julie P; Whitehouse, Chris A; Bavari, Sina

    2014-08-01

    High content image-based screening was developed as an approach to test a protease inhibitor small molecule library for antiviral activity against Rift Valley fever virus (RVFV) and to determine their mechanism of action. RVFV is the causative agent of severe disease of humans and animals throughout Africa and the Arabian Peninsula. Of the 849 compounds screened, 34 compounds exhibited ≥ 50% inhibition against RVFV. All of the hit compounds could be classified into 4 distinct groups based on their unique chemical backbone. Some of the compounds also showed broad antiviral activity against several highly pathogenic RNA viruses including Ebola, Marburg, Venezuela equine encephalitis, and Lassa viruses. Four hit compounds (C795-0925, D011-2120, F694-1532 and G202-0362), which were most active against RVFV and showed broad-spectrum antiviral activity, were selected for further evaluation for their cytotoxicity, dose response profile, and mode of action using classical virological methods and high-content imaging analysis. Time-of-addition assays in RVFV infections suggested that D011-2120 and G202-0362 targeted virus egress, while C795-0925 and F694-1532 inhibited virus replication. We showed that D011-2120 exhibited its antiviral effects by blocking microtubule polymerization, thereby disrupting the Golgi complex and inhibiting viral trafficking to the plasma membrane during virus egress. While G202-0362 also affected virus egress, it appears to do so by a different mechanism, namely by blocking virus budding from the trans Golgi. F694-1532 inhibited viral replication, but also appeared to inhibit overall cellular gene expression. However, G202-0362 and C795-0925 did not alter any of the morphological features that we examined and thus may prove to be good candidates for antiviral drug development. Overall this work demonstrates that high-content image analysis can be used to screen chemical libraries for new antivirals and to determine their mechanism of action and

  5. Oncolytic activity of Sindbis virus in human oral squamous carcinoma cells.

    Science.gov (United States)

    Saito, K; Uzawa, K; Kasamatsu, A; Shinozuka, K; Sakuma, K; Yamatoji, M; Shiiba, M; Shino, Y; Shirasawa, H; Tanzawa, H

    2009-08-18

    Sindbis virus (SIN) infection causes no or only mild symptoms (fever, rash, and arthralgia) in humans. However, SIN has a strong cytopathic effect (CPE) on various cancer cells. This study focuses on the oncolytic activity of SIN AR399 on oral cancer cells compared with reovirus, a well-known oncolytic virus that targets cancer cells. We analysed the cytotoxicity and growth of SIN in 13 oral squamous cell carcinoma (OSCC) cell lines (HSC-2, HSC-3, HSC-4, Ca9-22, H-1, Sa-3, KON, KOSC-2, OK-92, HO-1-N1, SCC-4, SAT, SKN-3) and normal human oral keratinocytes (NHOKs). Sindbis virus infection induced CPE in 12 OSCC cell lines at a low multiplicity of infection (MOI) of 0.01, but not in the OSCC cell line, HSC-4 or NHOKs. Sindbis viral growth was not observed in NHOKs, whereas high SIN growth was observed in all OSCC cell lines, including HCS-4. The cytotoxicity and growth of SIN was the same as reovirus at an MOI of 20 in 12 OSCC cell lines. The CPE was shown, by terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labelling assays, to be apoptotic cell death. Furthermore, quantitative RT-PCR of mRNA in HSC-3 and HSC-4 cells after SIN infection showed that activation of caspases, cytochrome c, and IkappaBalpha was associated with SIN-induced apoptosis. As a replication-competent oncolytic virus, SIN may be a useful therapeutic modality for oral cancers.

  6. Antiviral activity of the "Virus Blocking Factor" (VBF) derived i.a. from Pelargonium extract and Sambucus juice against different human-pathogenic cold viruses in vitro.

    Science.gov (United States)

    Fal, Andrzej M; Conrad, Frank; Schönknecht, Karina; Sievers, Hartwig; Pawińska, Anna

    The in-vitro antiviral activity of the "Virus Blocking Factor" (VBF), a combination of Pelargonium extract and Sambucus juice with addition of Betaglucan 1,3 / 1,6, Zincum gluconium, Acidum ascorbicum, was studied against human pathogenic viruses: Influenza A H1N1 (FluA H1N1), Rhinovirus B subtype 14 (HRV14), Respiratory Syncytial Virus (RSV), Parainfluenzavirus subtype 3 (Para 3), and Adenovirus C subtype 5 (Adeno 5). Antiviral activity was assessed using plaque-reduction assays after adding the test substance post infection of the MDCK, HeLa and HEp-2 cells with the viruses. Ribavirin Virazol and - in case of Adenovirus an internal laboratory standard - were used as positive controls. Cytotoxic effects of VBF and VBF Control onto the virus permissive MDCK, HeLa and HEp-2 cells were examined. Non-toxic concentrations of VBF were determined by the Methylthiazoletetrazolium test (MTT-Test). In all antiviral studies VBF showed (2.1%) a dose-dependent antiviral activity against FluA H1N1 and HRV14 at non-toxic concentrations. A very strong effect was demonstrated in concentrations of 2.5% and 1.25% where replication of H1N1 and HRV14 was nearly completely blocked. Dose-dependent antiviral activity was detectable against RSV in a concentration range of 1.25% to 0.63% of the test item. Due to toxic side effects of a 2.5% concentration at least a "minor effect" of about 30% (1.25% solution) against Para 3 infected HEp-2 cells could be determined. Concerning Adeno 5 not any antiviral activity could be demonstrated in all studies with all tested substance concentrations of VBF. VBF Control did not show any cytotoxicity and antiviral effects. Further research is needed to elucidate clinical effect of VBF.

  7. A dual vaccine against influenza & Alzheimer's disease failed to enhance anti-β-amyloid antibody responses in mice with pre-existing virus specific memory.

    Science.gov (United States)

    Davtyan, Hayk; Ghochikyan, Anahit; Hovakimyan, Armine; Davtyan, Arpine; Cadagan, Richard; Marleau, Annette M; Albrecht, Randy A; García-Sastre, Adolfo; Agadjanyan, Michael G

    2014-12-15

    Novel dual vaccine, WSN-Aβ(1-10), based on the recombinant influenza virus, expressing immunodominant B-cell epitope of β-amyloid, simultaneously induced therapeutically potent anti-Aβ and anti-influenza antibodies. In this study we showed that boosting of WSN-WT primed mice with WSN-Aβ(1-10) enhances anti-viral, but fails to induce anti-Aβ antibody responses. This inhibition is associated with expression of Aβ(1-10) within the context of an inactivated influenza virus vaccine. These results demonstrate that the use of an inactivated influenza virus as a carrier for AD vaccine may not be applicable due to the possible inhibition of anti-Aβ antibody response in individuals previously vaccinated or infected with influenza. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Two proteins with reverse transcriptase activities associated with hepatitis B virus-like particles

    International Nuclear Information System (INIS)

    Bavand, M.R.; Laub, O.

    1988-01-01

    Recent studies suggest that hepatitis B virus (HBV), despite being a DNA virus, replicates via an RNA intermediate. The HBV life cycle is therefore a permuted version of the RNA retroviral life cycle. Sequence homology between retroviral reverse transcriptase and the putative HBV polymerase gene product suggests the presence of an HBV reverse transcriptase. As yet, there has been no direct evidence that reverse transcriptase activity is present in the viral particle. The authors used activity gel analysis to detect the in situ catalytic activities of DNA polymerases after sodium dodecyl sulfate-polyacrylamide gel electrophorsis. These studies demonstrated that HBV-like particles secreted by a differentiated human hepatoma cell line tranfected with genomic HBV DNA contain two major polymerase activities which migrate as ∼90- and ∼70-kilodalton (kDa) proteins. This demonstrated, for the first time, that HBV-like particles contain a novel DNA polymerase-reverse transcriptase activity. Furthermore, they propose that the 70-kDa reverse transcriptase may be produced by proteolytic self-cleavage of the 90-kDa precursor protein

  9. Measles virus C protein impairs production of defective copyback double-stranded viral RNA and activation of protein kinase R.

    Science.gov (United States)

    Pfaller, Christian K; Radeke, Monte J; Cattaneo, Roberto; Samuel, Charles E

    2014-01-01

    Measles virus (MV) lacking expression of C protein (C(KO)) is a potent activator of the double-stranded RNA (dsRNA)-dependent protein kinase (PKR), whereas the isogenic parental virus expressing C protein is not. Here, we demonstrate that significant amounts of dsRNA accumulate during C(KO) mutant infection but not following parental virus infection. dsRNA accumulated during late stages of infection and localized with virus replication sites containing N and P proteins. PKR autophosphorylation and stress granule formation correlated with the timing of dsRNA appearance. Phospho-PKR localized to dsRNA-containing structures as revealed by immunofluorescence. Production of dsRNA was sensitive to cycloheximide but resistant to actinomycin D, suggesting that dsRNA is a viral product. Quantitative PCR (qPCR) analyses revealed reduced viral RNA synthesis and a steepened transcription gradient in C(KO) virus-infected cells compared to those in parental virus-infected cells. The observed alterations were further reflected in lower viral protein expression levels and reduced C(KO) virus infectious yield. RNA deep sequencing confirmed the viral RNA expression profile differences seen by qPCR between C(KO) mutant and parental viruses. After one subsequent passage of the C(KO) virus, defective interfering RNA (DI-RNA) with a duplex structure was obtained that was not seen with the parental virus. We conclude that in the absence of C protein, the amount of PKR activator RNA, including DI-RNA, is increased, thereby triggering innate immune responses leading to impaired MV growth.

  10. Activation and Inactivation of Primary Human Immunodeficiency Virus Envelope Glycoprotein Trimers by CD4-Mimetic Compounds

    Science.gov (United States)

    Madani, Navid; Princiotto, Amy M.; Zhao, Connie; Jahanbakhshsefidi, Fatemeh; Mertens, Max; Herschhorn, Alon; Melillo, Bruno; Smith, Amos B.

    2016-01-01

    ABSTRACT Human immunodeficiency virus type 1 (HIV-1) entry into cells is mediated by the viral envelope glycoproteins (Env), a trimer of three gp120 exterior glycoproteins, and three gp41 transmembrane glycoproteins. The metastable Env is triggered to undergo entry-related conformational changes when gp120 binds sequentially to the receptors, CD4 and CCR5, on the target cell. Small-molecule CD4-mimetic compounds (CD4mc) bind gp120 and act as competitive inhibitors of gp120-CD4 engagement. Some CD4mc have been shown to trigger Env prematurely, initially activating Env function, followed by rapid and irreversible inactivation. Here, we study CD4mc with a wide range of anti-HIV-1 potencies and demonstrate that all tested CD4mc are capable of activating as well as inactivating Env function. Biphasic dose-response curves indicated that the occupancy of the protomers in the Env trimer governs viral activation versus inactivation. One CD4mc bound per Env trimer activated HIV-1 infection. Envs with two CD4mc bound were activated for infection of CD4-negative, CCR5-positive cells, but the infection of CD4-positive, CCR5-positive cells was inhibited. Virus was inactivated when all three Env protomers were occupied by the CD4mc, and gp120 shedding from the Env trimer was increased in the presence of some CD4mc. Env reactivity and the on rates of CD4mc binding to the Env trimer were found to be important determinants of the potency of activation and entry inhibition. Cross-sensitization of Env protomers that do not bind the CD4mc to neutralization by an anti-V3 antibody was not evident. These insights into the mechanism of antiviral activity of CD4mc should assist efforts to optimize their potency and utility. IMPORTANCE The trimeric envelope glycoproteins of human immunodeficiency virus type 1 (HIV-1) mediate virus entry into host cells. Binding to the host cell receptors, CD4 and CCR5, triggers changes in the conformation of the HIV-1 envelope glycoprotein trimer important

  11. Inactivation efficacy of non-thermal plasma activated solutions against Newcastle disease virus.

    Science.gov (United States)

    Su, Xia; Tian, Ying; Zhou, Hongzhuan; Li, Yinglong; Zhang, Zhenhua; Jiang, Beiyu; Yang, Bing; Zhang, Jue; Fang, Jing

    2018-02-23

    In recent years, plasma activated solution (PAS) have made a good progress in the disinfection of medical device, tooth whitening, fruit preservation. In this study, we investigated the inactivation efficacy of Newcastle disease virus by PAS. Water, 0.9% NaCl and 0.3% H 2 O 2 were excited by plasma to obtain the corresponding solutions PAS(H 2 O), PAS(NaCl) and PAS(H 2 O 2 ). The complete inactivation of virus after PAS treatment for 30 min was confirmed by the embryo lethality assay (ELA) and hemagglutination (HA) test. Scanning electron microscopy (SEM) results showed that the morphology of the viral particle changed under PAS treatments. The total protein concentration of virus decreased by bradford protein assay due to PAS treatment. The nucleic acid integrity assay demonstrated that viral RNA degraded into smaller fragments. Moreover, the physicochemical properties of PAS including ORP, electric conductivity, H 2 O 2 concentration and electron spin resonance spectra analysis indicated that reactive oxygen and nitrogen species play a major role in the virus inactivation. Therefore, PAS, as an environmentally friendly method, would be a promising alternative strategy for application in the poultry industries. Importance Newcastle disease (ND) as an infectious viral disease of avian species caused significant economic losses to domestic animal and poultry industry. The traditional chemical sanitizers, such as chlorine-based products, are associated with risks of by-products formation with carcinogenic effect and environmental pollution. Based on these, plasma activated water as a green disinfection product is a promising alternative applied in stock farming and sterilization in hospitals and public places. In this study, we explored the inactivation efficacy of different plasma activated solution (PAS) against NDV and the possible mechanism between PAS and NDV. Our results demonstrated that reactive oxygen and nitrogen species detected in PAS, including short

  12. Anti-equine arteritis virus activity of ethanolic extract and compounds from Origanum vulgare

    Directory of Open Access Journals (Sweden)

    Daiane Einhardt Blank

    2017-05-01

    Full Text Available The equine arteritis virus (EAV is responsible by an important respiratory and reproductive disease in equine populations and there is no specific antiviral treatment available. The objective of this study was to investigate the activity of an ethanolic crude extract of Origanum vulgare (EEO and of isolated compound caffeic acid, p-coumaric acid, rosmarinic acid, quercetin, luteolin, carnosol, carnosic acid, kaempferol and apigenin against EAV. The assays were performed using non-cytotoxic concentrations. The antiviral activity was monitored initially by cytopathic effect inhibition (CPE assay in RK13 cells in the presence or absence of EEO. Pre-incubated cells with EEO were also examined to show prophylactic effect. Direct viral inactivation by EEO and isolated compounds was evaluated by incubation at 37°C or 20°C. After the incubation period, the infectivity was immediately determined by virus titrations on cell cultures and expressed as 50% tissue culture infective dose (TCID50/100 µL. There was significant virucidal activity of EEO and of the compounds caffeic acid, p-coumaric acid, quercetin, carnosic acid and kaempferol. When EEO was added after infection, EEO inhibited the virus growth in infected cells, as evidenced by significant reduction of the viral titre. The results provide evidence that the EEO exhibit an inhibitory effect anti-EAV. Among the main compounds evaluated, caffeic acid, p-coumaric acid, carnosic acid, kaempferol and mainly quercetin, contributed to the activity of EEO. EEO may represent a good prototype for the development of a new antiviral agent, presenting promising for combating arteriviruses infections.

  13. Rapid estimation of binding activity of influenza virus hemagglutinin to human and avian receptors.

    Directory of Open Access Journals (Sweden)

    Yang Cao

    2011-04-01

    Full Text Available A critical step for avian influenza viruses to infect human hosts and cause epidemics or pandemics is acquisition of the ability of the viral hemagglutinin (HA to bind to human receptors. However, current global influenza surveillance does not monitor HA binding specificity due to a lack of rapid and reliable assays. Here we report a computational method that uses an effective scoring function to quantify HA-receptor binding activities with high accuracy and speed. Application of this method reveals receptor specificity changes and its temporal relationship with antigenicity changes during the evolution of human H3N2 viruses. The method predicts that two amino acid differences at 222 and 225 between HAs of A/Fujian/411/02 and A/Panama/2007/99 viruses account for their differences in binding to both avian and human receptors; this prediction was verified experimentally. The new computational method could provide an urgently needed tool for rapid and large-scale analysis of HA receptor specificities for global influenza surveillance.

  14. Hepatitis B virus activity in patients with anti-hepatitis C virus antibody positivity and hepatitis B antigen positivity.

    Science.gov (United States)

    Haushofer, Alexander C; Hauer, René; Brunner, Harald; Köller, Ursula; Trubert-Exinger, Doris; Halbmayer, Walter Michael; Haas, Josef; Kessler, Harald H

    2002-12-01

    Co-infection with hepatitis B virus (HBV) and HCV seems to be relatively frequent. There might be a mutual influence on replication activity of HBV and HCV. To determine the HBV activity in patients with serum HCV RNA and HBsAg positivity and in those with confirmed anti-HCV antibody and HBsAg positivity but serum HCV RNA negativity. A total of 1,200 anti-HCV antibody positive samples were investigated. Samples of HCV RNA and HBsAg positive patients were compared with those of confirmed anti-HCV and HBsAg positive but serum HCV RNA negative patients. HBV activity was tested with the quantitative Cobas Amplicor HBV Monitor Test (Roche Diagnostic Systems, Pleasanton, CA). Of all studied patients with chronic hepatitis C (serum HCV RNA positivity) only 1.0% were found to be HBsAg positive. In contrast, of all patients with confirmed anti-HCV positivity but serum HCV RNA negativity, 11.9% tested HBsAg positive. The median of HBV DNA levels of patients with serum HCV RNA positivity and HBeAg seroconversion (4.0 x 10(2) HBV DNA copies per ml) was found to be slightly lower than that of patients with serum HCV RNA negativity and HBeAg seroconversion (2.5 x 10(3) HBV DNA copies per ml; P>0.05). The median of HBV DNA levels of patients with serum HCV RNA positivity but without HBeAg seroconversion (1.1 x 10(4) HBV DNA copies per ml) was found to be significantly lower than that of patients with serum HCV RNA negativity but without HBeAg seroconversion (2.6 x 10(7) HBV DNA copies per ml; P<0.05). A mutual effect on HBV and HCV replication could be observed. The molecular assay for quantification of serum HBV DNA was found to be useful for the routine diagnostic laboratory.

  15. Circulating intercellular adhesion molecule-1 (ICAM-1) as an early and sensitive marker for virus-induced T cell activation

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Johansen, J; Marker, O

    1995-01-01

    mice, clearly demonstrating that T cells were mandatory. Analysis of MHC class I and MHC class II-deficient mice revealed that either CD4+ or CD8+ T cells alone are sufficient, despite a markedly reduced inflammatory exudate in the former animals. These results indicate that virus-activated T cells......The effect of systemic virus infection on the level of circulating ICAM-1 (cICAM-1) in serum, and the role of virus-activated T cells in this context, were studied using the murine lymphocytic choriomeningitis virus infection as primary model system. A marked virus-induced elevation in cICAM-1...... in serum was revealed, the presence of which coincided with the phase of virus-induced T cell activation. However, high levels of cICAM-1 in serum were observed well before maximal T cell activation could be demonstrated. No increase in cICAM-1 was observed in the serum of infected T cell-deficient nude...

  16. Active Monitoring of Travelers for Ebola Virus Disease-New York City, October 25, 2014-December 29, 2015.

    Science.gov (United States)

    Saffa, Alhaji; Tate, Anna; Ezeoke, Ifeoma; Jacobs-Wingo, Jasmine; Iqbal, Maryam; Baumgartner, Jennifer; Fine, Anne; Perri, Bianca R; McIntosh, Natasha; Levy Stennis, Natalie; Lee, Kristen; Peterson, Eric; Jones, Lucretia; Helburn, Lisa; Heindrichs, Caroline; Guthartz, Seth; Chamany, Shadi; Starr, David; Scaccia, Allison; Raphael, Marisa; Varma, Jay K; Vora, Neil M

    The CDC recommended active monitoring of travelers potentially exposed to Ebola virus during the 2014 West African Ebola virus disease outbreak, which involved daily contact between travelers and health authorities to ascertain the presence of fever or symptoms for 21 days after the travelers' last potential Ebola virus exposure. From October 25, 2014, to December 29, 2015, the New York City Department of Health and Mental Hygiene (DOHMH) monitored 5,359 persons for Ebola virus disease, corresponding to 5,793 active monitoring events. Most active monitoring events were in travelers classified as low (but not zero) risk (n = 5,778; 99%). There were no gaps in contact with DOHMH of ≥2 days during 95% of active monitoring events. Instances of not making any contact with travelers decreased after CDC began distributing mobile telephones at the airport. Ebola virus disease-like symptoms or a temperature ≥100.0°F were reported in 122 (2%) active monitoring events. In the final month of active monitoring, an optional health insurance enrollment referral was offered for interested travelers, through which 8 travelers are known to have received coverage. Because it is possible that active monitoring will be used again for an infectious threat, the experience we describe might help to inform future such efforts.

  17. Viroporin Activity of the Foot-and-Mouth Disease Virus Non-Structural 2B Protein.

    Directory of Open Access Journals (Sweden)

    Da Ao

    Full Text Available Viroporins are a family of low-molecular-weight hydrophobic transmembrane proteins that are encoded by various animal viruses. Viroporins form transmembrane pores in host cells via oligomerization, thereby destroying cellular homeostasis and inducing cytopathy for virus replication and virion release. Among the Picornaviridae family of viruses, the 2B protein encoded by enteroviruses is well understood, whereas the viroporin activity of the 2B protein encoded by the foot-and-mouth disease virus (FMDV has not yet been described. An analysis of the FMDV 2B protein domains by computer-aided programs conducted in this study revealed that this protein may contain two transmembrane regions. Further biochemical, biophysical and functional studies revealed that the protein possesses a number of features typical of a viroporin when it is overexpressed in bacterial and mammalian cells as well as in FMDV-infected cells. The protein was found to be mainly localized in the endoplasmic reticulum (ER, with both the N- and C-terminal domains stretched into the cytosol. It exhibited cytotoxicity in Escherichia coli, which attenuated 2B protein expression. The release of virions from cells infected with FMDV was inhibited by amantadine, a viroporin inhibitor. The 2B protein monomers interacted with each other to form both intracellular and extracellular oligomers. The Ca(2+ concentration in the cells increased, and the integrity of the cytoplasmic membrane was disrupted in cells that expressed the 2B protein. Moreover, the 2B protein induced intense autophagy in host cells. All of the results of this study demonstrate that the FMDV 2B protein has properties that are also found in other viroporins and may be involved in the infection mechanism of FMDV.

  18. Hepatitis C virus core protein potentiates proangiogenic activity of hepatocellular carcinoma cells.

    Science.gov (United States)

    Shao, Yu-Yun; Hsieh, Min-Shu; Wang, Han-Yu; Li, Yong-Shi; Lin, Hang; Hsu, Hung-Wei; Huang, Chung-Yi; Hsu, Chih-Hung; Cheng, Ann-Lii

    2017-10-17

    Increased angiogenic activity has been demonstrated in hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC), but the mechanism was unclear. To study the role of HCV core protein, we used tube formation and Matrigel plug assays to assess the proangiogenic activity of an HCC cell line, HuH7, and 2 of its stable clones-HuH7-core-high and HuH7-core-low, with high and low HCV core protein expression, respectively. In both assays, HuH7-core-high and HuH7-core-low cells dose-dependently induced stronger angiogenesis than control cells. HuH7 cells with HCV core protein expression showed increased mRNA and protein expression of vascular endothelial growth factor (VEGF). VEGF inhibition by bevacizumab reduced the proangiogenic activity of HuH7-core-high cells. The promotor region of VEGF contains the binding site of activator protein-1 (AP-1). Compared with controls, HuH7-core-high cells had an increased AP-1 activity and nuclear localization of phospho-c-jun. AP-1 inhibition using either RNA knockdown or AP-1 inhibitors reduced the VEGF mRNA expression and the proangiogenic activity of HuH7-core-high cells. Among 131 tissue samples from HCC patients, HCV-related HCC revealed stronger VEGF expression than did hepatitis B virus-related HCC. In conclusion, increased VEGF expression through AP-1 activation is a crucial mechanism underlying the proangiogenic activity of the HCV core protein in HCC cells.

  19. Aryl Hydrocarbon Receptor Activation Reduces Dendritic Cell Function during Influenza Virus Infection

    Science.gov (United States)

    Jin, Guang-Bi; Moore, Amanda J.; Head, Jennifer L.; Neumiller, Joshua J.; Lawrence, B. Paige

    2010-01-01

    It has long been known that activation of the aryl hydrocarbon receptor (AhR) by ligands such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suppresses T cell–dependent immune responses; however, the underlying cellular targets and mechanism remain unclear. We have previously shown that AhR activation by TCDD reduces the proliferation and differentiation of influenza virus–specific CD8+ T cells through an indirect mechanism; suggesting that accessory cells are critical AhR targets during infection. Respiratory dendritic cells (DCs) capture antigen, migrate to lymph nodes, and play a key role in activating naive CD8+ T cells during respiratory virus infection. Herein, we report an examination of how AhR activation alters DCs in the lung and affects their trafficking to and function in the mediastinal lymph nodes (MLN) during infection with influenza virus. We show that AhR activation impairs lung DC migration and reduces the ability of DCs isolated from the MLN to activate naive CD8+ T cells. Using novel AhR mutant mice, in which the AhR protein lacks its DNA-binding domain, we show that the suppressive effects of TCDD require that the activated AhR complex binds to DNA. These new findings suggest that AhR activation by chemicals from our environment impacts DC function to stimulate naive CD8+ T cells and that immunoregulatory genes within DCs are critical targets of AhR. Moreover, our results reinforce the idea that environmental signals and AhR ligands may contribute to differential susceptibilities and responses to respiratory infection. PMID:20498003

  20. Innate Defense against Influenza A Virus: Activity of Human Neutrophil Defensins and Interactions of Defensins with Surfactant Protein D

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L.; White, Mitchell R.; Tecle, Tesfaldet

    2006-01-01

    Surfactant protein D (SP-D) plays important roles in innate host defense against influenza A virus (IAV) infection, in part by modifying interactions with neutrophils. Human neutrophil defensins (HNPs) inhibit infectivity of enveloped viruses, including IAV. Our goal in this study was to characte......Surfactant protein D (SP-D) plays important roles in innate host defense against influenza A virus (IAV) infection, in part by modifying interactions with neutrophils. Human neutrophil defensins (HNPs) inhibit infectivity of enveloped viruses, including IAV. Our goal in this study...... fluid and reduced the antiviral activity of bronchoalveolar lavage fluid. HNP-1 and -2 differed somewhat in their independent antiviral activity and their binding to SP-D. These results are relevant to the early phase of host defense against IAV, and suggest a complex interplay between SP-D and HNPs...

  1. Features of Recently Transmitted HIV-1 Clade C Viruses that Impact Antibody Recognition: Implications for Active and Passive Immunization.

    Science.gov (United States)

    Rademeyer, Cecilia; Korber, Bette; Seaman, Michael S; Giorgi, Elena E; Thebus, Ruwayhida; Robles, Alexander; Sheward, Daniel J; Wagh, Kshitij; Garrity, Jetta; Carey, Brittany R; Gao, Hongmei; Greene, Kelli M; Tang, Haili; Bandawe, Gama P; Marais, Jinny C; Diphoko, Thabo E; Hraber, Peter; Tumba, Nancy; Moore, Penny L; Gray, Glenda E; Kublin, James; McElrath, M Juliana; Vermeulen, Marion; Middelkoop, Keren; Bekker, Linda-Gail; Hoelscher, Michael; Maboko, Leonard; Makhema, Joseph; Robb, Merlin L; Abdool Karim, Salim; Abdool Karim, Quarraisha; Kim, Jerome H; Hahn, Beatrice H; Gao, Feng; Swanstrom, Ronald; Morris, Lynn; Montefiori, David C; Williamson, Carolyn

    2016-07-01

    The development of biomedical interventions to reduce acquisition of HIV-1 infection remains a global priority, however their potential effectiveness is challenged by very high HIV-1 envelope diversity. Two large prophylactic trials in high incidence, clade C epidemic regions in southern Africa are imminent; passive administration of the monoclonal antibody VRC01, and active immunization with a clade C modified RV144-like vaccines. We have created a large representative panel of C clade viruses to enable assessment of antibody responses to vaccines and natural infection in Southern Africa, and we investigated the genotypic and neutralization properties of recently transmitted clade C viruses to determine how viral diversity impacted antibody recognition. We further explore the implications of these findings for the potential effectiveness of these trials. A panel of 200 HIV-1 Envelope pseudoviruses was constructed from clade C viruses collected within the first 100 days following infection. Viruses collected pre-seroconversion were significantly more resistant to serum neutralization compared to post-seroconversion viruses (p = 0.001). Over 13 years of the study as the epidemic matured, HIV-1 diversified (p = 0.0009) and became more neutralization resistant to monoclonal antibodies VRC01, PG9 and 4E10. When tested at therapeutic levels (10ug/ml), VRC01 only neutralized 80% of viruses in the panel, although it did exhibit potent neutralization activity against sensitive viruses (IC50 titres of 0.42 μg/ml). The Gp120 amino acid similarity between the clade C panel and candidate C-clade vaccine protein boosts (Ce1086 and TV1) was 77%, which is 8% more distant than between CRF01_AE viruses and the RV144 CRF01_AE immunogen. Furthermore, two vaccine signature sites, K169 in V2 and I307 in V3, associated with reduced infection risk in RV144, occurred less frequently in clade C panel viruses than in CRF01_AE viruses from Thailand. Increased resistance of pre

  2. Fullerene Derivatives Strongly Inhibit HIV-1 Replication by Affecting Virus Maturation without Impairing Protease Activity.

    Science.gov (United States)

    Martinez, Zachary S; Castro, Edison; Seong, Chang-Soo; Cerón, Maira R; Echegoyen, Luis; Llano, Manuel

    2016-10-01

    Three compounds (1, 2, and 3) previously reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase were studied, but only fullerene derivatives 1 and 2 showed strong antiviral activity on the replication of HIV-1 in human CD4(+) T cells. However, these compounds did not inhibit infection by single-round infection vesicular stomatitis virus glycoprotein G (VSV-G)-pseudotyped viruses, indicating no effect on the early steps of the viral life cycle. In contrast, analysis of single-round infection VSV-G-pseudotyped HIV-1 produced in the presence of compound 1 or 2 showed a complete lack of infectivity in human CD4(+) T cells, suggesting that the late stages of the HIV-1 life cycle were affected. Quantification of virion-associated viral RNA and p24 indicates that RNA packaging and viral production were unremarkable in these viruses. However, Gag and Gag-Pol processing was affected, as evidenced by immunoblot analysis with an anti-p24 antibody and the measurement of virion-associated reverse transcriptase activity, ratifying the effect of the fullerene derivatives on virion maturation of the HIV-1 life cycle. Surprisingly, fullerenes 1 and 2 did not inhibit HIV-1 protease in an in vitro assay at the doses that potently blocked viral infectivity, suggesting a protease-independent mechanism of action. Highlighting the potential therapeutic relevance of fullerene derivatives, these compounds block infection by HIV-1 resistant to protease and maturation inhibitors. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Low dose influenza virus challenge in the ferret leads to increased virus shedding and greater sensitivity to oseltamivir.

    Science.gov (United States)

    Marriott, Anthony C; Dove, Brian K; Whittaker, Catherine J; Bruce, Christine; Ryan, Kathryn A; Bean, Thomas J; Rayner, Emma; Pearson, Geoff; Taylor, Irene; Dowall, Stuart; Plank, Jenna; Newman, Edmund; Barclay, Wendy S; Dimmock, Nigel J; Easton, Andrew J; Hallis, Bassam; Silman, Nigel J; Carroll, Miles W

    2014-01-01

    Ferrets are widely used to study human influenza virus infection. Their airway physiology and cell receptor distribution makes them ideal for the analysis of pathogenesis and virus transmission, and for testing the efficacy of anti-influenza interventions and vaccines. The 2009 pandemic influenza virus (H1N1pdm09) induces mild to moderate respiratory disease in infected ferrets, following inoculation with 106 plaque-forming units (pfu) of virus. We have demonstrated that reducing the challenge dose to 102 pfu delays the onset of clinical signs by 1 day, and results in a modest reduction in clinical signs, and a less rapid nasal cavity innate immune response. There was also a delay in virus production in the upper respiratory tract, this was up to 9-fold greater and virus shedding was prolonged. Progression of infection to the lower respiratory tract was not noticeably delayed by the reduction in virus challenge. A dose of 104 pfu gave an infection that was intermediate between those of the 106 pfu and 102 pfu doses. To address the hypothesis that using a more authentic low challenge dose would facilitate a more sensitive model for antiviral efficacy, we used the well-known neuraminidase inhibitor, oseltamivir. Oseltamivir-treated and untreated ferrets were challenged with high (106 pfu) and low (102 pfu) doses of influenza H1N1pdm09 virus. The low dose treated ferrets showed significant delays in innate immune response and virus shedding, delayed onset of pathological changes in the nasal cavity, and reduced pathological changes and viral RNA load in the lung, relative to untreated ferrets. Importantly, these observations were not seen in treated animals when the high dose challenge was used. In summary, low dose challenge gives a disease that more closely parallels the disease parameters of human influenza infection, and provides an improved pre-clinical model for the assessment of influenza therapeutics, and potentially, influenza vaccines.

  4. Modulation of mitogen-activated protein kinase-activated protein kinase 3 by hepatitis C virus core protein

    DEFF Research Database (Denmark)

    Ngo, HT; Pham, Long; Kim, JW

    2013-01-01

    and protein levels of MAPKAPK3 were elevated in both HCV subgenomic replicon cells and cell culture-derived HCV (HCVcc)-infected cells. Silencing of MAPKAPK3 expression resulted in decreases in both protein and HCV infectivity levels but not in the intracellular HCV RNA level. We showed that MAPKAPK3......Hepatitis C virus (HCV) is highly dependent on cellular proteins for its own propagation. In order to identify the cellular factors involved in HCV propagation, we performed protein microarray assays using the HCV core protein as a probe. Of ~9,000 host proteins immobilized in a microarray......, approximately 100 cellular proteins were identified as HCV core-interacting partners. Of these candidates, mitogen-activated protein kinase-activated protein kinase 3 (MAPKAPK3) was selected for further characterization. MAPKAPK3 is a serine/threonine protein kinase that is activated by stress and growth...

  5. Activation and Evasion of Innate Antiviral Immunity by Herpes Simplex Virus

    Directory of Open Access Journals (Sweden)

    Søren R. Paludan

    2009-11-01

    Full Text Available Herpes simplex virus (HSV, a human pathogenic virus, has evolved several strategies to evade the production and function of interferons (IFNs and cytokines generated by the innate immune system to restrict the virus. Equilibrium exists between the virus and the immune response, and a shift in this delicate balance either restricts the virus or enhances virus spread and tissue damage. Therefore, understanding of the cytokine response generated after HSV infection and the underlying virus-cell interactions is essential to improve our understanding of viral pathogenesis. This review summarizes the current knowledge on induction and evasion of the innate immune response by HSV.

  6. Highly activated RNA silencing via strong induction of dicer by one virus can interfere with the replication of an unrelated virus

    Science.gov (United States)

    Chiba, Sotaro; Suzuki, Nobuhiro

    2015-01-01

    Viruses often coinfect single host organisms in nature. Depending on the combination of viruses in such coinfections, the interplay between them may be synergistic, apparently neutral with no effect on each other, or antagonistic. RNA silencing is responsible for many cases of interference or cross-protection between viruses, but such antagonistic interactions are usually restricted to closely related strains of the same viral species. In this study, we present an unprecedented example of RNA silencing-mediated one-way interference between unrelated viruses in a filamentous model fungus, Cryphonectria parasitica. The replication of Rosellinia necatrix victorivirus 1 (RnVV1; Totiviridae) was strongly impaired by coinfection with the prototypic member of the genus Mycoreovirus (MyRV1) or a mutant of the prototype hypovirus (Cryphonectria hypovirus 1, CHV1) lacking the RNA silencing suppressor (CHV1-Δp69). This interference was associated with marked transcriptional induction of key genes in antiviral RNA silencing, dicer-like 2 (dcl2) and argonaute-like 2 (agl2), following MyRV1 or CHV1-Δp69 infection. Interestingly, the inhibition of RnVV1 replication was reproduced when the levels of dcl2 and agl2 transcripts were elevated by transgenic expression of a hairpin construct of an endogenous C. parasitica gene. Disruption of dcl2 completely abolished the interference, whereas that of agl2 did not always lead to its abolishment, suggesting more crucial roles of dcl2 in antiviral defense. Taken altogether, these results demonstrated the susceptible nature of RnVV1 to the antiviral silencing in C. parasitica activated by distinct viruses or transgene-derived double-stranded RNAs and provide insight into the potential for broad-spectrum virus control mediated by RNA silencing. PMID:26283371

  7. Structure and behaviour of proteins, nucleic acids and viruses from vibrational Raman optical activity

    DEFF Research Database (Denmark)

    Barron, L.D.; Blanch, E.W.; McColl, I.H.

    2003-01-01

    On account of its sensitivity to chirality Raman optical activity (ROA), which may be measured as a small difference in vibrational Raman scattering from chiral molecules in right- and left-circularly polarized incident light, is a powerful probe of structure and behaviour of biomolecules...... is especially favourable for fold determination using pattern recognition techniques. This article gives a brief account of the ROA technique and presents the ROA spectra of a selection of proteins, nucleic acids and viruses that illustrate the applications of ROA spectroscopy in biomolecular research....

  8. Rapid Active Assay for the Detection of Antibodies to West Nile Virus in Chickens

    Science.gov (United States)

    2008-01-01

    virus activity in Latin America and the Caribbean. Rev Panam Salud Publica 19: 112–117. 8. Campbell GL, Marfin AA, Lanciotti RS, Gubler DJ, 2002. West...Born and T. Y . Morozova. Financial support: This study was supported by DOE Grant DE-F C52-04NA25455. Disclaimer: In conducting research using animals...M, Ru- binshtein E, Itzhaki A, Mishal J, Siegman-Igra Y , Kitzes R, Pick N, Landau Z, Wolf D, Bin H, Mendelson E, Pitlik SD, Weinberger M, 2001

  9. Suppression of human immunodeficiency virus type 1 activity in vitro by oligonucleotides which form intramolecular tetrads.

    Science.gov (United States)

    Rando, R F; Ojwang, J; Elbaggari, A; Reyes, G R; Tinder, R; McGrath, M S; Hogan, M E

    1995-01-27

    An oligonucleotide (I100-15) composed of only deoxyguanosine and thymidine was able to inhibit human immunodeficiency virus type-1 (HIV-1) in culture assay systems. I100-15 did not block virus entry into cells but did reduce viral-specific transcripts. As assessed by NMR and polyacrylamide gel methods, I100-15 appears to form a structure in which two stacked guanosine tetrads are connected by three two-base long loops. Structure/activity experiments indicated that formation of intramolecular guanosine tetrads was necessary to achieve maximum antiviral activity. The single deoxyguanosine nucleotide present in each loop was found to be extremely important for the overall antiviral activity. The toxicity of I100-15 was determined to be well above the 50% effective dose (ED50) in culture which yielded a high therapeutic index (> 100). The addition of a cholesterol moiety to the 3' terminus of I100-15 (I100-23) reduced the ED50 value to less than 50 nM (from 0.12 microM for I100-15) and increased the duration of viral suppression to greater than 21 days (versus 7-10 days for I100-15) after removal of the drug from infected cell cultures. The favorable therapeutic index of such molecules coupled with the prolonged suppression of HIV-1, suggest that such compounds further warrant investigation as potential therapeutic agents.

  10. DNA distribution and respiratory activity of Spodoptera frugiperda populations infected with wild-type and recombinant Autographa californica nuclear polyhedrosis virus.

    Science.gov (United States)

    Schopf, B; Howaldt, M W; Bailey, J E

    1990-07-01

    Spodoptera frugiperda cells were infected with a wild-type Autographa californica nuclear polyhedrosis virus and with a recombinant Autographa californica nuclear polyhedrosis virus. The recombinant virus was derived from the wild-type virus and produced beta-galactosidase instead of polyhedrin. The changes in cell size, cell growth, viability, DNA distribution, and respiratory activity were followed through the time course of the infection. The DNA content as measured by flow cytometry of infected cells increased to approximately 1.8 times the value of uninfected cells and the distributions of single-cell DNA content of the infected cells were strongly deformed. Early in the infection the respiratory activity passed through a maximum. The mitochondrial activity based on Rhodamine 123 labelling of cells infected with the recombinant virus, as determined by flow cytometry, also passed through a maximum at 24 h post infection while the mitochondrial activity of cells infected with the wild-type virus continued to increase. Evolution of single-cell mitochondrial activity was different in uninfected populations and in populations infected with wild-type and with recombinant virus. In all experiments performed, the recombinant virus influenced cell behavior and the measured parameters earlier than the wild-type virus. The influence of the multiplicity of infection was stronger for the wild-type virus than for the recombinant virus.

  11. Regulation of ROS in transmissible gastroenteritis virus-activated apoptotic signaling.

    Science.gov (United States)

    Ding, Li; Zhao, Xiaomin; Huang, Yong; Du, Qian; Dong, Feng; Zhang, Hongling; Song, Xiangjun; Zhang, Wenlong; Tong, Dewen

    2013-12-06

    Transmissible gastroenteritis virus (TGEV), an enteropathogenic coronavirus, causes severe lethal watery diarrhea and dehydration in piglets. Previous studies indicate that TGEV infection induces cell apoptosis in host cells. In this study, we investigated the roles and regulation of reactive oxygen species (ROS) in TGEV-activated apoptotic signaling. The results showed that TGEV infection induced ROS accumulation, whereas UV-irradiated TGEV did not promote ROS accumulation. In addition, TGEV infection lowered mitochondrial transmembrane potential in PK-15 cell line, which could be inhibited by ROS scavengers, pyrrolidinedithiocarbamic (PDTC) and N-acetyl-l-cysteine (NAC). Furthermore, the two scavengers significantly inhibited the activation of p38 MAPK and p53 and further blocked apoptosis occurrence through suppressing the TGEV-induced Bcl-2 reduction, Bax redistribution, cytochrome c release and caspase-3 activation. These results suggest that oxidative stress pathway might be a key element in TGEV-induced apoptosis and TGEV pathogenesis. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Epizootic activity of Murray Valley encephalitis and Kunjin viruses in an aboriginal community in the southeast Kimberley region of Western Australia: results of mosquito fauna and virus isolation studies.

    Science.gov (United States)

    Broom, Annette K; Lindsay, Michael D A; Wright, Anthony E; Smith, David W; Mackenzie, John S

    2003-09-01

    We undertook annual surveys of flavivirus activity in the community of Billiluna in the southeast Kimberley region of Western Australia between 1989 and 2001 [corrected]. Culex annulirostris was the dominant mosquito species, particularly in years of above average rains and flooding. Murray Valley encephalitis (MVE) virus was isolated in 8 of the 13 years of the study from seven mosquito species, but more than 90% of the isolates were from Cx. annulirostris. The results suggest that MVE virus is epizootic in the region, w ith activity only apparent in years with average or above average rainfall and increased numbers of Cx. annulirostris. High levels of MVE virus activity and associated human cases were detected only once (in 1993) during the survey period. Activity of MVE virus could only be partially correlated with wet season rainfall and flooding, suggesting that a number of other factors must also be considered to accurately predict MVE virus activity at such communities.

  13. Dryocrassin ABBA, a novel active substance for use against amantadine-resistant H5N1 avian influenza virus.

    Science.gov (United States)

    Ou, Changbo; Zhang, Qiang; Wu, Guojiang; Shi, Ningning; He, Cheng

    2015-01-01

    The occurrence of multi-drug resistant highly pathogenic avian influenza virus (HPAIV) strains highlights the urgent need for strategies for the prevention and control of avian influenza virus. The aim of our current study is to evaluate the antiviral activity of dryocrassin ABBA isolated from Rhizoma Dryopteridis Crassirhizomatis (RDC) against an amantadine-resistant H5N1 (A/Chicken/Hebei/706/2005) strain in a mouse model. Post inoculation with HPAIV H5N1 virus in mice, the survival rate was 87, 80, and 60% respectively in the 33, 18, and 12.5 mg/kg dryocrassin ABBA-treated groups. On the other hand, the survival rate was 53 and 20%, respectively in the amantadine-treated group and untreated group. Mice administered with dryocrassin ABBA or amantadine showed a significant weight increase compared to the untreated group. Moreover, 33 and 18 mg/kg dryocrassin ABBA have decreased lung index (P >0.05) and virus loads (P ABBA-treated groups compared to the amantadine group and the untreated group. Moreover, the concentrations of IL-12 in drug-treated groups were significantly (P ABBA provided mice protection against avian influenza virus H5N1 by inhibiting inflammation and reducing virus loads. Dryocrassin ABBA is a potential novel lead compound which had antiviral effects on amantadine-resistant avian influenza virus H5N1 infection.

  14. Hepatitis B virus e antigen induces activation of rat hepatic stellate cells

    Energy Technology Data Exchange (ETDEWEB)

    Zan, Yanlu [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Yuxia, E-mail: yzhang@wehi.edu.au [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China); Tien, Po, E-mail: tienpo@sun.im.ac.cn [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China)

    2013-06-07

    Highlights: •HBeAg expression in HSCs induced production of ECM protein and liver fibrotic markers. •The activation and proliferation of HSCs were mediated by TGF-β. •HBeAg protein purified from cell medium directly activated HSCs. -- Abstract: Chronic hepatitis B virus infection is a major cause of hepatic fibrosis, leading to liver cirrhosis and hepatocellular carcinoma. Hepatitis B virus e antigen (HBeAg) is an accessory protein of HBV, not required for viral replication but important for natural infection in vivo. Hepatic stellate cells (HSCs) are the major producers of excessive extracellular matrix during liver fibrogenesis. Therefore, we examined the influence of HBeAg on HSCs. The rat HSC line HSC-T6 was transfected with HBeAg plasmids, and expression of α-smooth muscle actin, collagen I, transforming growth factor-β1 (TGF-β), and tissue inhibitors of metalloproteinase 1 (TIMP-1) was investigated by quantitative real-time PCR. The proliferation of HSCs was determined by MTS analysis. HBeAg transduction induced up-regulation of these fibrogenic genes and proliferation of HSCs. We found that HBeAg induced TGF-β secretion in HSCs, and the activation of HSCs was prevented by a neutralizing anti-TGF-β antibody. Depletion and addition of HBeAg protein in conditioned medium from HSC-T6 cells transduced with HBeAg indicated that HBeAg directly induced the activation and proliferation of rat primary HSCs. Taken together, HBeAg induces the activation and proliferation of HSCs, mainly mediated by TGF-β, and HBeAg protein purified from cell medium can directly activate HSCs.

  15. Hepatitis B virus e antigen induces activation of rat hepatic stellate cells

    International Nuclear Information System (INIS)

    Zan, Yanlu; Zhang, Yuxia; Tien, Po

    2013-01-01

    Highlights: •HBeAg expression in HSCs induced production of ECM protein and liver fibrotic markers. •The activation and proliferation of HSCs were mediated by TGF-β. •HBeAg protein purified from cell medium directly activated HSCs. -- Abstract: Chronic hepatitis B virus infection is a major cause of hepatic fibrosis, leading to liver cirrhosis and hepatocellular carcinoma. Hepatitis B virus e antigen (HBeAg) is an accessory protein of HBV, not required for viral replication but important for natural infection in vivo. Hepatic stellate cells (HSCs) are the major producers of excessive extracellular matrix during liver fibrogenesis. Therefore, we examined the influence of HBeAg on HSCs. The rat HSC line HSC-T6 was transfected with HBeAg plasmids, and expression of α-smooth muscle actin, collagen I, transforming growth factor-β1 (TGF-β), and tissue inhibitors of metalloproteinase 1 (TIMP-1) was investigated by quantitative real-time PCR. The proliferation of HSCs was determined by MTS analysis. HBeAg transduction induced up-regulation of these fibrogenic genes and proliferation of HSCs. We found that HBeAg induced TGF-β secretion in HSCs, and the activation of HSCs was prevented by a neutralizing anti-TGF-β antibody. Depletion and addition of HBeAg protein in conditioned medium from HSC-T6 cells transduced with HBeAg indicated that HBeAg directly induced the activation and proliferation of rat primary HSCs. Taken together, HBeAg induces the activation and proliferation of HSCs, mainly mediated by TGF-β, and HBeAg protein purified from cell medium can directly activate HSCs

  16. Telomerase Activity Impacts on Epstein-Barr Virus Infection of AGS Cells

    Science.gov (United States)

    Rac, Jürgen; Haas, Florian; Schumacher, Andrina; Middeldorp, Jaap M.; Delecluse, Henri-Jacques; Speck, Roberto F.

    2015-01-01

    The Epstein-Barr virus (EBV) is transmitted from host-to-host via saliva and is associated with epithelial malignancies including nasopharyngeal carcinoma (NPC) and some forms of gastric carcinoma (GC). Nevertheless, EBV does not transform epithelial cells in vitro where it is rapidly lost from infected primary epithelial cells or epithelial tumor cells. Long-term infection by EBV, however, can be established in hTERT-immortalized nasopharyngeal epithelial cells. Here, we hypothesized that increased telomerase activity in epithelial cells enhances their susceptibility to infection by EBV. Using HONE-1, AGS and HEK293 cells we generated epithelial model cell lines with increased or suppressed telomerase activity by stable ectopic expression of hTERT or of a catalytically inactive, dominant negative hTERT mutant. Infection experiments with recombinant prototypic EBV (rB95.8), recombinant NPC EBV (rM81) with increased epithelial cell tropism compared to B95.8, or recombinant B95.8 EBV with BZLF1-knockout that is not able to undergo lytic replication, revealed that infection frequencies positively correlate with telomerase activity in AGS cells but also partly depend on the cellular background. AGS cells with increased telomerase activity showed increased expression mainly of latent EBV genes, suggesting that increased telomerase activity directly acts on the EBV infection of epithelial cells by facilitating latent EBV gene expression early upon virus inoculation. Thus, our results indicate that infection of epithelial cells by EBV is a very selective process involving, among others, telomerase activity and cellular background to allow for optimized host-to-host transmission via saliva. PMID:25856387

  17. Insights into the structure and activity of prototype foamy virus RNase H

    Directory of Open Access Journals (Sweden)

    Leo Berit

    2012-02-01

    Full Text Available Abstract Background RNase H is an endonuclease that hydrolyzes the RNA strand in RNA/DNA hybrids. Retroviral reverse transcriptases harbor a C-terminal RNase H domain whose activity is essential for viral replication. The RNase H degrades the viral genomic RNA after the first DNA strand is synthesized. Here, we report the biophysical and enzymatic properties of the RNase H domain of prototype foamy virus (PFV as an independently purified protein. Sequence comparisons with other retroviral RNases H indicated that PFV RNase H harbors a basic protrusion, including a basic loop and the so-called C-helix, which was suggested to be important for activity and substrate binding and is absent in the RNase H domain of human immunodeficiency virus. So far, no structure of a retroviral RNase H containing a C-helix is available. Results RNase H activity assays demonstrate that the PFV RNase H domain is active, although its activity is about 200-fold reduced as compared to the full length protease-reverse transcriptase enzyme. Fluorescence equilibrium titrations with an RNA/DNA substrate revealed a KD for the RNase H domain in the low micromolar range which is about 4000-fold higher than that of the full-length protease-reverse transcriptase enzyme. Analysis of the RNase H cleavage pattern using a [32P]-labeled substrate indicates that the independent RNase H domain cleaves the substrate non-specifically. The purified RNase H domain exhibits a well defined three-dimensional structure in solution which is stabilized in the presence of Mg2+ ions. Conclusions Our data demonstrate that the independent PFV RNase H domain is structured and active. The presence of the C-helix in PFV RNase H could be confirmed by assigning the protein backbone and calculating the chemical shift index using NMR spectroscopy.

  18. Characterization of hemagglutination activity of emerging Newcastle disease virus in Bangladesh

    Directory of Open Access Journals (Sweden)

    Helal Uddin

    2017-06-01

    Full Text Available Aim: Newcastle disease (ND is an important viral disease for poultry caused by avian paramyxovirus which can be identified by its nature of agglutination activity with red blood cell (RBC of different species. The study was aimed to characterize the hemagglutinating (HA activity of ND virus (NDV at three different temperatures using RBC of five avian species, six mammalian species, and eight different human blood groups. Materials and Methods: The study was conducted from January to December 2014 at Chittagong Veterinary and Animal Sciences University. Five avian and six different mammalian species were selected for the study. In each species, two blood samples were collected aseptically. Eight different blood groups (A+, A−, B+, B−, AB+, AB−, O+, and O− were studied in human. HA test was performed using two virus strains ND lasota and field isolate of very virulent NDV (VVNDV with mentioned species of RBC at chilling (4°C, incubating (37°C, and room temperature (24°C. Results: Avian RBC requires less time for agglutination than mammalian RBC. Incubation temperature (37°C requires lowest time and chilling temperature requires highest time for agglutination of RBC. Duck RBC requires lowest time (17.81 min while chicken RBC needs highest (57.5 min time for HA at incubation temperature and at chilling temperature, respectively, against ND lasota virus and with field strain. Goat RBC requires significantly higher time for HA (184.68 min at chilling temperature than other mammalian species. Human RBC requires almost similar time but O+ and O− blood group do not show any HA activity. Significant variation (p<0.05 found in quail RBC at incubation temperature. In mammalian species, a significant difference (p<0.05 has been observed in goat and horse RBC at chilling; horse and dog RBC at incubation; goat, horse, buffalo, and dog RBC at room temperature. In human, significant variation (p<0.05 has been found in A+, A− and B− blood group

  19. H2AX phosphorylation and DNA damage kinase activity are dispensable for herpes simplex virus replication.

    Science.gov (United States)

    Botting, Carolyn; Lu, Xu; Triezenberg, Steven J

    2016-01-27

    Herpes simplex virus type 1 (HSV-1) can establish both lytic and latent infections in humans. The phosphorylation of histone H2AX, a common marker of DNA damage, during lytic infection by HSV-1 is well established. However, the role(s) of H2AX phosphorylation in lytic infection remain unclear. Following infection of human foreskin fibroblasts by HSV-1 or HSV-2, we assayed the phosphorylation of H2AX in the presence of inhibitors of transcription, translation, or viral DNA replication, or in the presence of inhibitors of ATM and ATR kinases (KU-55933 and VE-821, respectively). We also assayed viral replication in fibroblasts in the presence of the kinase inhibitors or siRNAs specific for ATM and ATR, as well as in cell lines deficient for either ATR or ATM. The expression of viral immediate-early and early proteins (including the viral DNA polymerase), but not viral DNA replication or late protein expression, were required for H2AX phosphorylation following HSV-1 infection. Inhibition of ATM kinase activity prevented HSV-stimulated H2AX phosphorylation but had only a minor effect on DNA replication and virus yield in HFF cells. These results differ from previous reports of a dramatic reduction in viral yield following chemical inhibition of ATM in oral keratinocytes or following infection of ATM(-/-) cells. Inhibition of the closely related kinase ATR (whether by chemical inhibitor or siRNA disruption) had no effect on H2AX phosphorylation and reduced viral DNA replication only moderately. During infection by HSV-2, H2AX phosphorylation was similarly dispensable but was dependent on both ATM activity and viral DNA replication. H2AX phosphorylation represents a cell type-specific and virus type-specific host response to HSV infection with little impact on viral infection.

  20. Measles virus C protein suppresses gamma-activated factor formation and virus-induced cell growth arrest

    International Nuclear Information System (INIS)

    Yokota, Shin-ichi; Okabayashi, Tamaki; Fujii, Nobuhiro

    2011-01-01

    Measles virus (MeV) produces two accessory proteins, V and C, from the P gene. These accessory proteins have been reported to contribute to efficient virus proliferation through the modulation of host cell events. Our previous paper described that Vero cell-adapted strains of MeV led host cells to growth arrest through the upregulation of interferon regulatory factor 1 (IRF-1), and wild strains did not. In the present study, we found that C protein expression levels varied among MeV strains in infected SiHa cells. C protein levels were inversely correlated with IRF-1 expression levels and with cell growth arrest. Forced expression of C protein released cells from growth arrest. C-deficient recombinant virus efficiently upregulated IRF-1 and caused growth arrest more efficiently than the wild-type virus. C protein preferentially bound to phosphorylated STAT1 and suppressed STAT1 dimer formation. We conclude that MeV C protein suppresses IFN-γ signaling pathway via inhibition of phosphorylated STAT1 dimerization.

  1. Long terminal repeat sequences from virulent and attenuated equine infectious anemia virus demonstrate distinct promoter activities.

    Science.gov (United States)

    Zhou, Tao; Yuan, Xiu-Fang; Hou, Shao-Hua; Tu, Ya-Bin; Peng, Jin-Mei; Wen, Jian-Xin; Qiu, Hua-Ji; Wu, Dong-Lai; Chen, Huan-Chun; Wang, Xiao-Jun; Tong, Guang-Zhi

    2007-09-01

    In the early 1970s, the Chinese Equine Infectious Anemia Virus (EIAV) vaccine, EIAV(DLA), was developed through successive passages of a wild-type virulent virus (EIAV(L)) in donkeys in vivo and then in donkey macrophages in vitro. EIAV attenuation and cell tropism adaptation are associated with changes in both envelope and long terminal repeat (LTR). However, specific LTR changes during Chinese EIAV attenuation have not been demonstrated. In this study, we compared LTR sequences from both virulent and attenuated EIAV strains and documented the diversities of LTR sequence from in vivo and in vitro infections. We found that EIAV LTRs of virulent strains were homologous, while EIAV vaccine have variable LTRs. Interestingly, experimental inoculation of EIAV(DLA) into a horse resulted in a restriction of the LTR variation. Furthermore, LTRs from EIAV(DLA) showed higher Tat transactivated activity than LTRs from virulent strains. By using chimeric clones of wild-type LTR and vaccine LTR, the main difference of activity was mapped to the changes of R region, rather than U3 region.

  2. Japanese encephalitis virus activates autophagy as a viral immune evasion strategy.

    Science.gov (United States)

    Jin, Rui; Zhu, Wandi; Cao, Shengbo; Chen, Rui; Jin, Hui; Liu, Yang; Wang, Shaobo; Wang, Wei; Xiao, Gengfu

    2013-01-01

    In addition to manipulating cellular homeostasis and survivability, autophagy also plays a crucial role in numerous viral infections. In this study, we discover that Japanese encephalitis virus (JEV) infection results in the accumulation of microtubule-associated protein 1 light chain 3-II (LC3-II) protein and GFP-LC3 puncta in vitro and an increase in autophagosomes/autolysosomes in vivo. The fusion between autophagosomes and lysosomes is essential for virus replication. Knockdown of autophagy-related genes reduced JEV replication in vitro, as indicated by viral RNA and protein levels. We also note that JEV infection in autophagy-impaired cells displayed active caspases cleavage and cell death. Moreover, we find that JEV induces higher type I interferon (IFN) activation in cells deficient in autophagy-related genes as the cells exhibited increased phosphorylation and dimerization of interferon regulatory factor 3 (IRF3) and mitochondrial antiviral signaling protein (MAVS) aggregation. Finally, we find that autophagy is indispensable for efficient JEV replication even in an IFN-defective background. Overall, our studies provide the first description of the mechanism of the autophagic innate immune signaling pathway during JEV infection.

  3. A Role for Protein Phosphatase 2A in Regulating p38 Mitogen Activated Protein Kinase Activation and Tumor Necrosis Factor-Alpha Expression during Influenza Virus Infection

    Directory of Open Access Journals (Sweden)

    Anna H. Y. Law

    2013-04-01

    Full Text Available Influenza viruses of avian origin continue to pose pandemic threats to human health. Some of the H5N1 and H9N2 virus subtypes induce markedly elevated cytokine levels when compared with the seasonal H1N1 virus. We previously showed that H5N1/97 hyperinduces tumor necrosis factor (TNF-alpha through p38 mitogen activated protein kinase (MAPK. However, the detailed mechanisms of p38MAPK activation and TNF-alpha hyperinduction following influenza virus infections are not known. Negative feedback regulations of cytokine expression play important roles in avoiding overwhelming production of proinflammatory cytokines. Here we hypothesize that protein phosphatases are involved in the regulation of cytokine expressions during influenza virus infection. We investigated the roles of protein phosphatases including MAPK phosphatase-1 (MKP-1 and protein phosphatase type 2A (PP2A in modulating p38MAPK activation and downstream TNF-alpha expressions in primary human monocyte-derived macrophages (PBMac infected with H9N2/G1 or H1N1 influenza virus. We demonstrate that H9N2/G1 virus activated p38MAPK and hyperinduced TNF-alpha production in PBMac when compared with H1N1 virus. H9N2/G1 induced PP2A activity in PBMac and, with the treatment of a PP2A inhibitor, p38MAPK phosphorylation and TNF-alpha production were further increased in the virus-infected macrophages. However, H9N2/G1 did not induce the expression of PP2A indicating that the activation of PP2A is not mediated by p38MAPK in virus-infected PBMac. On the other hand, PP2A may not be the targets of H9N2/G1 in the upstream of p38MAPK signaling pathways since H1N1 also induced PP2A activation in primary macrophages. Our results may provide new insights into the control of cytokine dysregulation.

  4. Antiviral activity of the Lippia graveolens (Mexican oregano essential oil and its main compound carvacrol against human and animal viruses

    Directory of Open Access Journals (Sweden)

    Marciele Ribas Pilau

    2011-12-01

    Full Text Available Mexican oregano (Lippia graveolens is a plant found in Mexico and Central America that is traditionally used as a medicinal herb. In the present study, we investigated the antiviral activity of the essential oil of Mexican oregano and its major component, carvacrol, against different human and animal viruses. The MTT test (3-4,5-dimethythiazol-2yl-2,5-diphenyl tetrazolium bromide was conducted to determine the selectivity index (SI of the essential oil, which was equal to 13.1, 7.4, 10.8, 9.7, and 7.2 for acyclovir-resistant herpes simplex virus type 1 (ACVR-HHV-1, acyclovir-sensitive HHV-1, human respiratory syncytial virus (HRSV, bovine herpesvirus type 2 (BoHV-2, and bovine viral diarrhoea virus (BVDV, respectively. The human rotavirus (RV and BoHV-1 and 5 were not inhibited by the essential oil. Carvacrol alone exhibited high antiviral activity against RV with a SI of 33, but it was less efficient than the oil for the other viruses. Thus, Mexican oregano oil and its main component, carvacrol, are able to inhibit different human and animal viruses in vitro. Specifically, the antiviral effects of Mexican oregano oil on ACVR-HHV-1 and HRSV and of carvacrol on RV justify more detailed studies.

  5. Influenza A (H1N1) neuraminidase inhibitors from Vitis amurensis

    DEFF Research Database (Denmark)

    Nguyen, Ngoc Anh; Dao, Trong Tuan; Tung, Bui Thanh

    2011-01-01

    Recently, a novel H1N1 influenza A virus (H1N1/09 virus) was identified and considered a strong candidate for a novel influenza pandemic. As part of an ongoing anti-influenza screening programme on natural products, eight oligostilbenes were isolated as active principles from the methanol extract...

  6. Transmissible gastroenteritis virus infection induces cell apoptosis via activation of p53 signalling.

    Science.gov (United States)

    Huang, Yong; Ding, Li; Li, Zhaocai; Dai, Meiling; Zhao, Xiaomin; Li, Wei; Du, Qian; Xu, Xingang; Tong, Dewen

    2013-08-01

    Transmissible gastroenteritis virus (TGEV) infection induced apoptosis in several cell lines in vitro. Our previous studies demonstrated that TGEV could activate FasL- and mitochondria-mediated pathways to induce apoptosis in PK-15 cells. In this study, we investigated the regulation of p53 and p38 mitogen-activated protein kinases (MAPK) signalling pathways in the interaction of TGEV with host cells. We observed that TGEV infection decreased p300/CBP, downregulated MDM2 and promoted p53 phosphorylation at serines 15, 20 and 46, resulting in accumulation and activation of p53 in PK-15 cells. TGEV infection induced the transient activation of p38 MAPK in the early phase of inoculation and constant activation in the later phase of infection. However, UV-irradiated TGEV did not promote the activation of p53 and p38 MAPK in the later phase, whereas it only triggered the transient activation of p38 MAPK in the early phase. Blocking of p53 activation significantly inhibited the occurrence of apoptosis through suppressing the TGEV-induced FasL expression, Bcl-2 reduction, Bax and cytochrome c redistribution, while inhibition of p38 activity moderately blocked apoptosis induction and partly attenuated the accumulation and activation of p53. However, inhibition of p38 and p53 activity had no significant effects on viral gene transcription at 12 and 24 h post-infection. Taken together, these results demonstrated that TGEV infection promoted the activation of p38 MAPK and p53 signalling, and p53 signalling might play a dominant role in the regulation of cell apoptosis. These findings provide new insights into the function of p53 and p38 MAPK in the interaction of TGEV with host cells.

  7. Clinical development of reovirus for cancer therapy: An oncolytic virus with immune-mediated antitumor activity.

    Science.gov (United States)

    Gong, Jun; Sachdev, Esha; Mita, Alain C; Mita, Monica M

    2016-03-26

    Reovirus is a double-stranded RNA virus with demonstrated oncolysis or preferential replication in cancer cells. The oncolytic properties of reovirus appear to be dependent, in part, on activated Ras signaling. In addition, Ras-transformation promotes reovirus oncolysis by affecting several steps of the viral life cycle. Reovirus-mediated immune responses can present barriers to tumor targeting, serve protective functions against reovirus systemic toxicity, and contribute to therapeutic efficacy through antitumor immune-mediated effects via innate and adaptive responses. Preclinical studies have demonstrated the broad anticancer activity of wild-type, unmodified type 3 Dearing strain reovirus (Reolysin(®)) across a spectrum of malignancies. The development of reovirus as an anticancer agent and available clinical data reported from 22 clinical trials will be reviewed.

  8. Evidence that the RNAseH activity of the duck hepatitis B virus is unable to act on exogenous substrates

    Directory of Open Access Journals (Sweden)

    Tavis John E

    2001-07-01

    Full Text Available Abstract Background The hepadnaviral reverse transcriptase can synthesize DNA on its native RNA template within viral cores but it is usually unable to synthesize DNA employing exogenous nucleic acids as a template. The mechanism of this template commitment is unknown. Here we provide evidence that the RNAseH activity of duck hepatitis B virus reverse transcriptase may also be unable to act on exogenous substrates. Results RNAseH assays were performed under a wide variety of conditions employing substrate RNAs of Duck Hepatitis B Virus sequence annealed to complementary DNA oligonucleotides and permeabilized intracellular viral core particles. Temperature, pH, cation type, salt concentration, substrate concentration, and the sequences of the cleavage sites were varied, and the effects of ATP and dNTPs on RNAseH activity were examined. duck hepatitis B virus RNAseH activity was not detected under any of these conditions, although E. coli or Avian Myeloblastosis Virus RNAseH activity could be detected under all conditions. Access of the RNA substrate to the enzyme within the viral cores was confirmed. Conclusions These results imply that the RNAseH activity of the DHBV reverse transcriptase may not be able to degrade exogenous RNA:DNA heteroduplexes, although it can degrade heteroduplexes of the same sequence generated during reverse transcription of the endogenous RNA template. Therefore, the RNAseH activity appears to be "substrate committed" in a manner similar to the template commitment observed for the DNA polymerase activity.

  9. Human immunodeficiency virus-like particles activate multiple types of immune cells

    International Nuclear Information System (INIS)

    Sailaja, Gangadhara; Skountzou, Ioanna; Quan, Fu-Shi; Compans, Richard W.; Kang, Sang-Moo

    2007-01-01

    The rapid spread of human immunodeficiency virus (HIV) worldwide makes it a high priority to develop an effective vaccine. Since live attenuated or inactivated HIV is not likely to be approved as a vaccine due to safety concerns, HIV virus like particles (VLPs) offer an attractive alternative because they are safe due to the lack of a viral genome. Although HIV VLPs have been shown to induce humoral and cellular immune responses, it is important to understand the mechanisms by which they induce such responses and to improve their immunogenicity. We generated HIV VLPs, and VLPs containing Flt3 ligand (FL), a dendritic cell growth factor, to target VLPs to dendritic cells, and investigated the roles of these VLPs in the initiation of adaptive immune responses in vitro and in vivo. We found that HIV-1 VLPs induced maturation of dendritic cells and monocyte/macrophage populations in vitro and in vivo, with enhanced expression of maturation markers and cytokines. Dendritic cells pulsed with VLPs induced activation of splenocytes resulting in increased production of cytokines. VLPs containing FL were found to increase dendritic cells and monocyte/macrophage populations in the spleen when administered to mice. Administration of VLPs induced acute activation of multiple types of cells including T and B cells as indicated by enhanced expression of the early activation marker CD69 and down-regulation of the homing receptor CD62L. VLPs containing FL were an effective form of antigen in activating immune cells via dendritic cells, and immunization with HIV VLPs containing FL resulted in enhanced T helper type 2-like immune responses

  10. Immunomodulating and antiviral activities of Uncaria tomentosa on human monocytes infected with Dengue Virus-2.

    Science.gov (United States)

    Reis, Sonia Regina I N; Valente, Ligia M M; Sampaio, André L; Siani, Antonio C; Gandini, Mariana; Azeredo, Elzinandes L; D'Avila, Luiz A; Mazzei, José L; Henriques, Maria das Graças M; Kubelka, Claire F

    2008-03-01

    Uncaria tomentosa (Willd.) DC., a large woody vine native to the Amazon and Central American rainforests has been used medicinally by indigenous peoples since ancient times and has scientifically proven immunomodulating, anti-inflammatory, cytotoxic and antioxidant activities. Several inflammatory mediators that are implicated in vascular permeability and shock are produced after Dengue Virus (DENV) infection by monocytes, the primary targets for virus replication. Here we assessed the immunoregulatory and antiviral activities from U. tomentosa-derived samples, which were tested in an in vitro DENV infection model. DENV-2 infected human monocytes were incubated with U. tomentosa hydro-alcoholic extract or either its pentacyclic oxindole alkaloid-enriched or non-alkaloid fractions. The antiviral activity was determined by viral antigen (DENV-Ag) detection in monocytes by flow cytometry. Our results demonstrated an in vitro inhibitory activity by both extract and alkaloidal fraction, reducing DENV-Ag+ cell rates in treated monocytes. A multiple microbead immunoassay was applied for cytokine determination (TNF-alpha, IFN-alpha, IL-6 and IL-10) in infected monocyte culture supernatants. The alkaloidal fraction induced a strong immunomodulation: TNF-alpha and IFN-alpha levels were significantly decreased and there was a tendency towards IL-10 modulation. We conclude that the alkaloidal fraction was the most effective in reducing monocyte infection rates and cytokine levels. The antiviral and immunomodulating in vitro effects from U. tomentosa pentacyclic oxindole alkaloids displayed novel properties regarding therapeutic procedures in Dengue Fever and might be further investigated as a promising candidate for clinical application.

  11. Activation-induced cytidine deaminase in B cells of hepatits C virus-related cryoglobulinaemic vasculitis.

    Science.gov (United States)

    Russi, S; Dammacco, F; Sansonno, S; Pavone, F; Sansonno, D

    2015-12-01

    Immunoglobulin variable region heavy chain (IgVH ) somatic gene diversification is instrumental in the transformation process that characterizes hepatitis C virus (HCV)-related B cell lymphoproliferative disorders. However, the extent to which activation-induced cytidine deaminase (AID), an enzyme essential for IgV gene somatic hypermutation (SHM), is active in cryoglobulinaemic vasculitis (CV) remains unclear. AID mRNA expression in the peripheral blood of 102 chronically hepatitis C virus (HCV)-infected patients (58 with and 44 without CV) and 26 healthy subjects was investigated using real-time reverse transcription-polymerase chain reaction (RT-PCR). The features of activation-induced cytidine deaminase (AID) protein and mRNA transcripts were explored in liver tissue biopsies and portal tracts isolated using laser capture microdissection. In chronically HCV-infected patients, AID mRNA expression was almost threefold higher in those with than in those without CV and sevenfold higher than in healthy subjects (median-fold: 6.68 versus 2.54, P = 0.03 and versus 0.95, P = 0.0003). AID transcript levels were significantly higher in polyclonal than in clonally restricted B cell preparations in either CV or non-CV patients (median-fold, 15.0 versus 2.70, P = 0.009 and 3.46 versus 1.58, P = 0.02, respectively). AID gene expression was found to be related negatively to age and virological parameters. AID protein was found in portal tracts containing inflammatory cells that, in several instances, expressed AID mRNA transcripts. Our data indicate that the aberrant expression of AID may reflect continuous B cell activation and sustained survival signals in HCV-related CV patients. © 2015 British Society for Immunology.

  12. Synthesis of Nucleoside Analogues with Potential Antiviral Activity against Negative Strand RNA Virus Targets

    Science.gov (United States)

    1989-11-01

    ye Paramyxovirus Human parainfluenza , mumps Morbillivirus Measles, Rinderpest (cattle) 9 canine distemper viruses Pneumovirus Respiratory syncytial...significant effect on man include Rabies virus1 0 and Vesicular Stomatitus virus (VSV) in the Americas and Bovine Ephemeral Fever virus in Australasia. Of the...structurally related to neplanocin A, namely 9-(trans-2’,trans-3’-dihydroxycyclo- pent-4’-enyl) derivatives, 4 and 5, are potent inhibitors of bovine liver

  13. Equine tetherin blocks retrovirus release and its activity is antagonized by equine infectious anemia virus envelope protein.

    Science.gov (United States)

    Yin, Xin; Hu, Zhe; Gu, Qinyong; Wu, Xingliang; Zheng, Yong-Hui; Wei, Ping; Wang, Xiaojun

    2014-01-01

    Human tetherin is a host restriction factor that inhibits replication of enveloped viruses by blocking viral release. Tetherin has an unusual topology that includes an N-terminal cytoplasmic tail, a single transmembrane domain, an extracellular domain, and a C-terminal glycosylphosphatidylinositol anchor. Tetherin is not well conserved across species, so it inhibits viral replication in a species-specific manner. Thus, studies of tetherin activities from different species provide an important tool for understanding its antiviral mechanism. Here, we report cloning of equine tetherin and characterization of its antiviral activity. Equine tetherin shares 53%, 40%, 36%, and 34% amino acid sequence identity with feline, human, simian, and murine tetherins, respectively. Like the feline tetherin, equine tetherin has a shorter N-terminal domain than human tetherin. Equine tetherin is localized on the cell surface and strongly blocks human immunodeficiency virus type 1 (HIV-1), simian immunodeficiency virus (SIV), and equine infectious anemia virus (EIAV) release from virus-producing cells. The antiviral activity of equine tetherin is neutralized by EIAV envelope protein, but not by the HIV-1 accessory protein Vpu, which is a human tetherin antagonist, and EIAV envelope protein does not counteract human tetherin. These results shed new light on our understanding of the species-specific tetherin antiviral mechanism.

  14. Dimerization Efficiency of Canine Distemper Virus Matrix Protein Regulates Membrane-Budding Activity.

    Science.gov (United States)

    Bringolf, Fanny; Herren, Michael; Wyss, Marianne; Vidondo, Beatriz; Langedijk, Johannes P; Zurbriggen, Andreas; Plattet, Philippe

    2017-08-15

    Paramyxoviruses rely on the matrix (M) protein to orchestrate viral assembly and budding at the plasma membrane. Although the mechanistic details remain largely unknown, structural data suggested that M dimers and/or higher-order oligomers may facilitate membrane budding. To gain functional insights, we employed a structure-guided mutagenesis approach to investigate the role of canine distemper virus (CDV) M protein self-assembly in membrane-budding activity. Three six-alanine-block (6A-block) mutants with mutations located at strategic oligomeric positions were initially designed. While the first one includes residues potentially residing at the protomer-protomer interface, the other two display amino acids located within two distal surface-exposed α-helices proposed to be involved in dimer-dimer contacts. We further focused on the core of the dimeric interface by mutating asparagine 138 (N138) to several nonconservative amino acids. Cellular localization combined with dimerization and coimmunopurification assays, performed under various denaturing conditions, revealed that all 6A-block mutants were impaired in self-assembly and cell periphery accumulation. These phenotypes correlated with deficiencies in relocating CDV nucleocapsid proteins to the cell periphery and in virus-like particle (VLP) production. Conversely, all M-N138 mutants remained capable of self-assembly, though to various extents, which correlated with proper accumulation and redistribution of nucleocapsid proteins at the plasma membrane. However, membrane deformation and VLP assays indicated that the M-N138 variants exhibiting the most reduced dimerization propensity were also defective in triggering membrane remodeling and budding, despite proper plasma membrane accumulation. Overall, our data provide mechanistic evidence that the efficiency of CDV M dimerization/oligomerization governs both cell periphery localization and membrane-budding activity. IMPORTANCE Despite the availability of

  15. Transmissible gastroenteritis virus infection induces NF-κB activation through RLR-mediated signaling.

    Science.gov (United States)

    Ding, Zhen; An, Kang; Xie, Lilan; Wu, Wei; Zhang, Ruoxi; Wang, Dang; Fang, Ying; Chen, Huanchun; Xiao, Shaobo; Fang, Liurong

    2017-07-01

    Transmissible gastroenteritis virus (TGEV) is a porcine enteric coronavirus which causes lethal severe watery diarrhea in piglets. The pathogenesis of TGEV is strongly associated with inflammation. In this study, we found that TGEV infection activates transcription factors NF-κB, IRF3 and AP-1 in a time- and dose-dependent manner in porcine kidney cells. Treatment with the NF-κB-specific inhibitor BAY11-7082 significantly decreased TGEV-induced proinflammatory cytokine production, but did not affect virus replication. Phosphorylation of NF-κB subunit p65 and proinflammatory cytokine production were greatly decreased after knockdown of retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) or its adaptors MAVS and STING, while only slight reduction was observed in cells following silencing of Toll-like receptor adaptors, MyD88 and TRIF. Furthermore, TGEV infection significantly upregulated mRNA expression of RIG-I and MDA5. Taken together, our results indicate that the RLR signaling pathway is involved in TGEV-induced inflammatory responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Novel recombinant adeno-associated viruses for Cre activated and inactivated transgene expression in neurons

    Directory of Open Access Journals (Sweden)

    Arpiar eSaunders

    2012-07-01

    Full Text Available Understanding the organization of the nervous system requires methods for dissecting the contributions of each component cell type to circuit function. One widely used approach combines genetic targeting of Cre recombinase to specific cell populations with infection of recombinant adeno-associated viruses (rAAVs whose transgene expression is activated by Cre (Cre-On. Distinguishing how the Cre-expressing neurons differ functionally from neighboring Cre-negative neurons requires rAAVs that are inactivated by Cre (Cre-Off and can be used in tandem with Cre-On viruses. Here we introduce two rAAV vectors that are inactivated by Cre and carry different fluorophore and optogenetic constructs. We demonstrate single and dual rAAV systems to achieve Cre-On and Cre-Off expression in spatially-intermingled cell populations of the striatum. Using these systems, we uncovered cryptic genomic interactions that occur between multiple Cre-sensitive rAAVs or between Cre-sensitive rAAVs and somatic Cre-conditional alleles and devised methods to avoid these interactions. Our data highlight both important experimental caveats associated with Cre-dependent rAAV use as well as opportunities for the development of improved rAAVs for gene delivery.

  17. Novel recombinant adeno-associated viruses for Cre activated and inactivated transgene expression in neurons

    Science.gov (United States)

    Saunders, Arpiar; Johnson, Caroline A.; Sabatini, Bernardo L.

    2012-01-01

    Understanding the organization of the nervous system requires methods for dissecting the contributions of each component cell type to circuit function. One widely used approach combines genetic targeting of Cre recombinase to specific cell populations with infection of recombinant adeno-associated viruses (rAAVs) whose transgene expression is activated by Cre (“Cre-On”). Distinguishing how the Cre-expressing neurons differ functionally from neighboring Cre-negative neurons requires rAAVs that are inactivated by Cre (“Cre-Off”) and can be used in tandem with Cre-On viruses. Here we introduce two rAAV vectors that are inactivated by Cre and carry different fluorophore and optogenetic constructs. We demonstrate single and dual rAAV systems to achieve Cre-On and Cre-Off expression in spatially-intermingled cell populations of the striatum. Using these systems, we uncovered cryptic genomic interactions that occur between multiple Cre-sensitive rAAVs or between Cre-sensitive rAAVs and somatic Cre-conditional alleles and devised methods to avoid these interactions. Our data highlight both important experimental caveats associated with Cre-dependent rAAV use as well as opportunities for the development of improved rAAVs for gene delivery. PMID:22866029

  18. Crystal structure of an active two-domain derivative of Rous sarcoma virus integrase.

    Science.gov (United States)

    Yang, Z N; Mueser, T C; Bushman, F D; Hyde, C C

    2000-02-18

    Integration of retroviral cDNA is a necessary step in viral replication. The virally encoded integrase protein and DNA sequences at the ends of the linear viral cDNA are required for this reaction. Previous studies revealed that truncated forms of Rous sarcoma virus integrase containing two of the three protein domains can carry out integration reactions in vitro. Here, we describe the crystal structure at 2.5 A resolution of a fragment of the integrase of Rous sarcoma virus (residues 49-286) containing both the conserved catalytic domain and a modulatory DNA-binding domain (C domain). The catalytic domains form a symmetric dimer, but the C domains associate asymmetrically with each other and together adopt a canted conformation relative to the catalytic domains. A binding path for the viral cDNA is evident spanning both domain surfaces, allowing modeling of the larger integration complexes that are known to be active in vivo. The modeling suggests that formation of an integrase tetramer (a dimer of dimers) is necessary and sufficient for joining both viral cDNA ends at neighboring sites in the target DNA. The observed asymmetric arrangement of C domains suggests that they could form a rotationally symmetric tetramer that may be important for bridging integrase complexes at each cDNA end.

  19. The anti-canine distemper virus activities of ex vivo-expanded canine natural killer cells.

    Science.gov (United States)

    Park, Ji-Yun; Shin, Dong-Jun; Lee, Soo-Hyeon; Lee, Je-Jung; Suh, Guk-Hyun; Cho, Duck; Kim, Sang-Ki

    2015-04-17

    Natural killer (NK) cells play critical roles in induction of antiviral effects against various viruses of humans and animals. However, few data on NK cell activities during canine distemper virus (CDV) infections are available. Recently, we established a culture system allowing activation and expansion of canine non-B, non-T, large granular NK lymphocytes from PBMCs of normal dogs. In the present study, we explored the ability of such expanded NK cells to inhibit CDV infection in vitro. Cultured CD3-CD5-CD21- NK cells produced large amounts of IFN-γ, exhibited highly upregulated expression of mRNAs encoding NK-cell-associated receptors, and demonstrated strong natural killing activity against canine tumor cells. Although the expanded NK cells were dose-dependently cytotoxic to both normal and CDV-infected Vero cells, CDV infection rendered Vero cells more susceptible to NK cells. Pretreatment with anti-CDV serum from hyperimmunized dogs enhanced the antibody-dependent cellular cytotoxicity (ADCC) of NK cells against CDV-infected Vero cells. The culture supernatants of NK cells, added before or after infection, dose-dependently inhibited both CDV replication and development of CDV-induced cytopathic effects (CPEs) in Vero cells. Anti-IFN-γ antibody neutralized the inhibitory effects of NK cell culture supernatants on CDV replication and CPE induction in Vero cells. Such results emphasize the potential significance of NK cells in controlling CDV infection, and indicate that NK cells may play roles both during CDV infection and in combating such infections, under certain conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Enhancing the Oncolytic Activity of CD133-Targeted Measles Virus: Receptor Extension or Chimerism with Vesicular Stomatitis Virus Are Most Effective

    Directory of Open Access Journals (Sweden)

    Dina Kleinlützum

    2017-06-01

    Full Text Available Therapy resistance and tumor recurrence are often linked to a small refractory and highly tumorigenic subpopulation of neoplastic cells, known as cancer stem cells (CSCs. A putative marker of CSCs is CD133 (prominin-1. We have previously described a CD133-targeted oncolytic measles virus (MV-CD133 as a promising approach to specifically eliminate CD133-positive tumor cells. Selectivity was introduced at the level of cell entry by an engineered MV hemagglutinin (H. The H protein was blinded for its native receptors and displayed a CD133-specific single-chain antibody fragment (scFv as targeting domain. Interestingly, MV-CD133 was more active in killing CD133-positive tumors than the unmodified MV-NSe despite being highly selective for its target cells. To further enhance the antitumoral activity of MV-CD133, we here pursued arming technologies, receptor extension, and chimeras between MV-CD133 and vesicular stomatitis virus (VSV. All newly generated viruses including VSV-CD133 were highly selective in eliminating CD133-positive cells. MV-CD46/CD133 killed in addition CD133-negative cells being positive for the MV receptors. In an orthotopic glioma model, MV-CD46/CD133 and MVSCD-CD133, which encodes the super cytosine deaminase, were most effective. Notably, VSV-CD133 caused fatal neurotoxicity in this tumor model. Use of CD133 as receptor could be excluded as being causative. In a subcutaneous tumor model of hepatocellular cancer, VSV-CD133 revealed the most potent oncolytic activity and also significantly prolonged survival of the mice when injected intravenously. Compared to MV-CD133, VSV-CD133 infected a more than 104-fold larger area of the tumor within the same time period. Our data not only suggest new concepts and approaches toward enhancing the oncolytic activity of CD133-targeted oncolytic viruses but also raise awareness about careful toxicity testing of novel virus types.

  1. Fluorescence-based monitoring of in vivo neural activity using a circuit-tracing pseudorabies virus.

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    Andrea E Granstedt

    Full Text Available The study of coordinated activity in neuronal circuits has been challenging without a method to simultaneously report activity and connectivity. Here we present the first use of pseudorabies virus (PRV, which spreads through synaptically connected neurons, to express a fluorescent calcium indicator protein and monitor neuronal activity in a living animal. Fluorescence signals were proportional to action potential number and could reliably detect single action potentials in vitro. With two-photon imaging in vivo, we observed both spontaneous and stimulated activity in neurons of infected murine peripheral autonomic submandibular ganglia (SMG. We optically recorded the SMG response in the salivary circuit to direct electrical stimulation of the presynaptic axons and to physiologically relevant sensory stimulation of the oral cavity. During a time window of 48 hours after inoculation, few spontaneous transients occurred. By 72 hours, we identified more frequent and prolonged spontaneous calcium transients, suggestive of neuronal or tissue responses to infection that influence calcium signaling. Our work establishes in vivo investigation of physiological neuronal circuit activity and subsequent effects of infection with single cell resolution.

  2. Predictors of active injection drug use in a cohort of patients infected with hepatitis C virus.

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    Reed, Carrie; Bliss, Caleb; Stuver, Sherri O; Heeren, Timothy; Tumilty, Sheila; Horsburgh, C Robert; Samet, Jeffrey H; Cotton, Deborah J

    2013-01-01

    We investigated potential risk factors for active injection drug use (IDU) in an inner-city cohort of patients infected with hepatitis C virus (HCV). We used log-binomial regression to identify factors independently associated with active IDU during the first 3 years of follow-up for the 289 participants who reported ever having injected drugs at baseline. Overall, 142 (49.1%) of the 289 participants reported active IDU at some point during the follow-up period. In a multivariate model, being unemployed (prevalence ratio [PR] = 1.93; 95% confidence interval [CI] = 1.24, 3.03) and hazardous alcohol drinking (PR = 1.67; 95% CI = 1.34, 2.08) were associated with active IDU. Smoking was associated with IDU but this association was not statistically significant. Patients with all 3 of those factors were 3 times as likely to report IDU during follow-up as those with 0 or 1 factor (PR = 3.3; 95% CI = 2.2, 4.9). Neither HIV coinfection nor history of psychiatric disease was independently associated with active IDU. Optimal treatment of persons with HCV infection will require attention to unemployment, alcohol use, and smoking in conjunction with IDU treatment and prevention.

  3. Elevation of Serum Acid Sphingomyelinase Activity in Children with Acute Respiratory Syncytial Virus Bronchiolitis.

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    Yoshida, Shuichiro; Noguchi, Atsuko; Kikuchi, Wataru; Fukaya, Hiroshi; Igarashi, Kiyoshi; Takahashi, Tsutomu

    2017-12-01

    Acid sphingomyelinase (ASM) is a lysosomal enzyme that hydrolyzes sphingomyelin into ceramide, a bioactive lipid to regulate cellular physiological functions. Thus, ASM activation has been reported as a key event in pathophysiological reactions including inflammation, cytokine release, oxidative stress, and endothelial damage in human diseases. Since ASM activation is associated with extracellular ASM secretion through unknown mechanisms, it can be detected by recognizing the elevation of secretory ASM (S-ASM) activity. Serum S-ASM activity has been reported to increase in chronic diseases, acute cardiac diseases, and systemic inflammatory diseases. However, the serum S-ASM has not been investigated in common acute illness. This study was designed to evaluate serum S-ASM activity in children with common acute illness. Fifty children with common acute illness and five healthy children were included in this study. The patients were categorized into five groups based on clinical diagnoses: acute respiratory syncytial virus (RSV) bronchiolitis, adenovirus infection, streptococcal infection, asthma, and other infections due to unknown origin. The serum S-ASM activity was significantly elevated at 6.9 ± 1.6 nmol/0.1 mL/6 h in the group of acute RSV bronchiolitis patients compared with healthy children who had a mean level of 1.8 ± 0.8 nmol/0.1 mL/6 h (p ASM activity was not significantly elevated. The results suggest an association of ASM activation with RSV infection, a cause for common acute illness. This is the first report to describe the elevation of serum S-ASM activity in respiratory tract infection.

  4. Humoral markers of active Epstein-Barr virus infection associate with anti-extractable nuclear antigen autoantibodies and plasma galectin-3 binding protein in systemic lupus erythematosus

    DEFF Research Database (Denmark)

    Rasmussen, N S; Nielsen, C T; Houen, G

    2016-01-01

    We investigated if signs of active Epstein-Barr virus and cytomegalovirus infections associate with certain autoantibodies and a marker of type I interferon activity in patients with systemic lupus erythematosus. IgM and IgG plasma levels against Epstein-Barr virus early antigen diffuse and cytom......We investigated if signs of active Epstein-Barr virus and cytomegalovirus infections associate with certain autoantibodies and a marker of type I interferon activity in patients with systemic lupus erythematosus. IgM and IgG plasma levels against Epstein-Barr virus early antigen diffuse...... and cytomegalovirus pp52 were applied as humoral markers of ongoing/recently active Epstein-Barr virus and cytomegalovirus infections, respectively. Plasma galectin-3 binding protein served as a surrogate marker of type I interferon activity. The measurements were conducted in 57 systemic lupus erythematosus patients...

  5. Activation of senescence-associated Dark-inducible (DIN) genes during infection contributes to enhanced susceptibility to plant viruses.

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    Fernández-Calvino, Lourdes; Guzmán-Benito, Irene; Del Toro, Francisco J; Donaire, Livia; Castro-Sanz, Ana B; Ruíz-Ferrer, Virginia; Llave, César

    2016-01-01

    Virus infections in plants cause changes in host gene expression that are common to other environmental stresses. In this work, we found extensive overlap in the transcriptional responses between Arabidopsis thaliana plants infected with Tobacco rattle virus (TRV) and plants undergoing senescence. This is exemplified by the up-regulation during infection of several senescence-associated Dark-inducible (DIN) genes, including AtDIN1 (Senescence 1, SEN1), AtDIN6 (Asparagine synthetase 1, AtASN1) and AtDIN11. DIN1, DIN6 and DIN11 homologues were also activated in Nicotiana benthamiana in response to TRV and Potato virus X (PVX) infection. Reduced TRV levels in RNA interference (RNAi) lines targeting AtDIN11 indicate that DIN11 is an important modulator of susceptibility to TRV in Arabidopsis. Furthermore, low accumulation of TRV in Arabidopsis protoplasts from RNAi lines suggests that AtDIN11 supports virus multiplication in this species. The effect of DIN6 on virus accumulation was negligible in Arabidopsis, perhaps as a result of gene or functional redundancy. However, TRV-induced silencing of NbASN, the DIN6 homologue in N. benthamiana, compromises TRV and PVX accumulation in systemically infected leaves. Interestingly, NbASN inactivation correlates with the appearance of morphological defects in infected leaves. We found that DIN6 and DIN11 regulate virus multiplication in a step prior to the activation of plant defence responses. We hypothesize on the possible roles of DIN6 and DIN11 during virus infection. © 2015 BSPP AND JOHN WILEY & SONS LTD.

  6. Somatic hypermutations confer rheumatoid factor activity in hepatitis C virus-associated mixed cryoglobulinemia.

    Science.gov (United States)

    Charles, Edgar D; Orloff, Michael I M; Nishiuchi, Eiko; Marukian, Svetlana; Rice, Charles M; Dustin, Lynn B

    2013-09-01

    Hepatitis C virus (HCV) is the most frequent cause of mixed cryoglobulinemia (MC), which is characterized by endothelial deposition of rheumatoid factor (RF)-containing immune complexes and end-organ vasculitis. MC is a lymphoproliferative disorder in which B cells express RF-like Ig, yet its precise antigenic stimulus is unknown. We have proposed that IgG-HCV immune complexes stimulate B cell expansion and somatic hypermutation (SHM)-induced affinity maturation in part via engagement of an RF-like B cell receptor. This study was undertaken to test the hypothesis that SHM augments RF activity. RFs cloned from single B cells from 4 patients with HCV-associated MC (HCV-MC) were expressed as IgM, IgG, or IgG Fab. Selected Ig were reverted to germline. RF activity of somatically mutated Ig and germline-reverted Ig was determined by enzyme-linked immunosorbent assay. Ig with SHM had RF activity, with the preference for binding being highest for IgG1, followed by IgG2 and IgG4, and lowest for IgG3, where there was no detectable binding. In contrast, reverted germline IgG exhibited markedly diminished RF activity. Competition with 1 μg/ml of protein A abrogated RF activity, suggesting specificity for IgG Fc. Swapping of mutated heavy-chain pairs and light-chain pairs also abrogated RF activity, suggesting that context-specific pairing of appropriate IgH and Igκ, in addition to SHM, is necessary for RF activity. SHM significantly contributes to RF activity in HCV-MC patients, suggesting that autoreactivity in these patients arises through antigen-dependent SHM, as opposed to nondeletion of autoreactive germline Ig. Copyright © 2013 by the American College of Rheumatology.

  7. Cytosolic 5'-triphosphate ended viral leader transcript of measles virus as activator of the RIG I-mediated interferon response.

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    Sébastien Plumet

    Full Text Available BACKGROUND: Double stranded RNA (dsRNA is widely accepted as an RNA motif recognized as a danger signal by the cellular sentries. However, the biology of non-segmented negative strand RNA viruses, or Mononegavirales, is hardly compatible with the production of such dsRNA. METHODOLOGY AND PRINCIPAL FINDINGS: During measles virus infection, the IFN-beta gene transcription was found to be paralleled by the virus transcription, but not by the virus replication. Since the expression of every individual viral mRNA failed to activate the IFN-beta gene, we postulated the involvement of the leader RNA, which is a small not capped and not polyadenylated RNA firstly transcribed by Mononegavirales. The measles virus leader RNA, synthesized both in vitro and in vivo, was efficient in inducing the IFN-beta expression, provided that it was delivered into the cytosol as a 5'-trisphosphate ended RNA. The use of a human cell line expressing a debilitated RIG-I molecule, together with overexpression studies of wild type RIG-I, showed that the IFN-beta induction by virus infection or by leader RNA required RIG-I to be functional. RIG-I binds to leader RNA independently from being 5-trisphosphate ended; while a point mutant, Q299A, predicted to establish contacts with the RNA, fails to bind to leader RNA. Since the 5'-triphosphate is required for optimal RIG-I activation but not for leader RNA binding, our data support that RIG-I is activated upon recognition of the 5'-triphosphate RNA end. CONCLUSIONS/SIGNIFICANCE: RIG-I is proposed to recognize Mononegavirales transcription, which occurs in the cytosol, while scanning cytosolic RNAs, and to trigger an IFN response when encountering a free 5'-triphosphate RNA resulting from a mislocated transcription activity, which is therefore considered as the hallmark of a foreign invader.

  8. Quantitative proteomic analysis reveals that transmissible gastroenteritis virus activates the JAK-STAT1 signaling pathway.

    Science.gov (United States)

    An, Kang; Fang, Liurong; Luo, Rui; Wang, Dang; Xie, Lilan; Yang, Jing; Chen, Huanchun; Xiao, Shaobo

    2014-12-05

    Transmissible gastroenteritis virus (TGEV), a porcine enteropathogenic coronavirus, causes lethal watery diarrhea and severe dehydration in piglets. In this study, liquid chromatography-tandem mass spectrometry coupled to isobaric tags for relative and absolute quantification labeling was used to quantitatively identify differentially expressed cellular proteins after TGEV infection in PK-15 cells. In total, 162 differentially expressed cellular proteins were identified, including 60 upregulated proteins and 102 downregulated proteins. These differentially expressed proteins were involved in the cell cycle, cellular growth and proliferation, the innate immune response, etc. Interestingly, many upregulated proteins were associated with interferon signaling, especially signal transducer and activator of transcription 1 (STAT1) and interferon-stimulated genes (ISGs). Immunoblotting and real-time quantitative reverse transcription polymerase chain reaction demonstrated that TGEV infection induces STAT1 phosphorylation and nuclear translocation, as well as ISG expression. This study for the first time reveals that TGEV induces interferon signaling from the point of proteomic analysis.

  9. Combination of Vaccine-Strain Measles and Mumps Viruses Enhances Oncolytic Activity against Human Solid Malignancies.

    Science.gov (United States)

    Son, Ho Anh; Zhang, LiFeng; Cuong, Bui Khac; Van Tong, Hoang; Cuong, Le Duy; Hang, Ngo Thu; Nhung, Hoang Thi My; Yamamoto, Naoki; Toan, Nguyen Linh

    2018-02-07

    Oncolytic measles and mumps viruses (MeV, MuV) have a potential for anti-cancer treatment. We examined the anti-tumor activity of MeV, MuV, and MeV-MuV combination (MM) against human solid malignancies (HSM). MeV, MuV, and MM targeted and significantly killed various cancer cell lines of HSM but not normal cells. MM demonstrated a greater anti-tumor effect and prolonged survival in a human prostate cancer xenograft tumor model compared to MeV and MuV. MeV, MuV, and MM significantly induced the expression of immunogenic cell death markers and enhanced spleen-infiltrating immune cells. In conclusion, MM combination significantly improves the treatment of human solid malignancies.

  10. Venezuelan Equine Encephalitis Virus Activity in the Gulf Coast Region of Mexico, 2003–2010

    Science.gov (United States)

    Adams, A. Paige; Navarro-Lopez, Roberto; Ramirez-Aguilar, Francisco J.; Lopez-Gonzalez, Irene; Leal, Grace; Flores-Mayorga, Jose M.; Travassos da Rosa, Amelia P. A.; Saxton-Shaw, Kali D.; Singh, Amber J.; Borland, Erin M.; Powers, Ann M.; Tesh, Robert B.; Weaver, Scott C.; Estrada-Franco, Jose G.

    2012-01-01

    Venezuelan equine encephalitis virus (VEEV) has been the causative agent for sporadic epidemics and equine epizootics throughout the Americas since the 1930s. In 1969, an outbreak of Venezuelan equine encephalitis (VEE) spread rapidly from Guatemala and through the Gulf Coast region of Mexico, reaching Texas in 1971. Since this outbreak, there have been very few studies to determine the northward extent of endemic VEEV in this region. This study reports the findings of serologic surveillance in the Gulf Coast region of Mexico from 2003–2010. Phylogenetic analysis was also performed on viral isolates from this region to determine whether there have been substantial genetic changes in VEEV since the 1960s. Based on the findings of this study, the Gulf Coast lineage of subtype IE VEEV continues to actively circulate in this region of Mexico and appears to be responsible for infection of humans and animals throughout this region, including the northern State of Tamaulipas, which borders Texas. PMID:23133685

  11. Venezuelan equine encephalitis virus activity in the Gulf Coast region of Mexico, 2003-2010.

    Directory of Open Access Journals (Sweden)

    A Paige Adams

    Full Text Available Venezuelan equine encephalitis virus (VEEV has been the causative agent for sporadic epidemics and equine epizootics throughout the Americas since the 1930s. In 1969, an outbreak of Venezuelan equine encephalitis (VEE spread rapidly from Guatemala and through the Gulf Coast region of Mexico, reaching Texas in 1971. Since this outbreak, there have been very few studies to determine the northward extent of endemic VEEV in this region. This study reports the findings of serologic surveillance in the Gulf Coast region of Mexico from 2003-2010. Phylogenetic analysis was also performed on viral isolates from this region to determine whether there have been substantial genetic changes in VEEV since the 1960s. Based on the findings of this study, the Gulf Coast lineage of subtype IE VEEV continues to actively circulate in this region of Mexico and appears to be responsible for infection of humans and animals throughout this region, including the northern State of Tamaulipas, which borders Texas.

  12. Spectral characterisation, antiviral activities, in silico ADMET and molecular docking of the compounds isolated from Tectona grandis to chikungunya virus.

    Science.gov (United States)

    K, Sangeetha; Purushothaman, Indu; S, Rajarajan

    2017-03-01

    Chikungunya infection is treated symptomatically with antipyretics and anti-inflammatory drugs without any specific antiviral drug till date. The lack of an approved antiviral drug and the emergence of virulent strains after 2006 epidemics emphasize the need for the development of potential antiviral drugs to Chikungunya virus. Hence, we studied the antiviral activity of the extracts and compounds isolated from Tectona grandis leaves to both the Asian and East central South African strains of Chikungunya virus. Five compounds were isolated from the ethanolic extract of Tectona grandis by bioactivity guided fractionation followed by Spectral Characterisation through GC-MS and NMR spectroscopy and investigated for the antiviral activity. Also in silico ADMET and Molecular Docking of the characterised compounds against the structural and non structural proteins of Chikungunya virus were performed. The characterised compound Benzene-1-carboxylic acid hexadeconate was effective at IC 50 3.036μg/ml (7.5μM) and 76.46μg/ml (189.02μM) to Asian and ECSA strain of CHIKV respectively. The compound showed desirable pharmacokinetic properties and significant molecular interactions with the E1 protein of Chikungunya virus by in silico analysis. Thus Benzene-1-carboxylic acid-2-hexadeconate isolated from Tectona grandis was found to be a promising drug candidate to both the Asian and ECSA strains of Chikungunya virus with high selectivity indices in comparison to the reference RNA antiviral drug Ribavirin. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. Antiviral activity of the adenosine analogue BCX4430 against West Nile virus and tick-borne flaviviruses.

    Science.gov (United States)

    Eyer, Luděk; Zouharová, Darina; Širmarová, Jana; Fojtíková, Martina; Štefánik, Michal; Haviernik, Jan; Nencka, Radim; de Clercq, Erik; Růžek, Daniel

    2017-06-01

    There are currently no approved antiviral therapies against medically important human flaviviruses. The imino-C-nucleoside BCX4430 shows broad-spectrum antiviral activity against a wide range of RNA viruses. Here, we demonstrate that BCX4430 inhibits tick-borne species of the genus Flavivirus; however, the antiviral effect varies against individual species. Micro-molar BCX4430 levels inhibited tick-borne encephalitis virus (TBEV); while, approximately 3-8-fold higher concentrations were needed to inhibit louping ill virus and Kyasanur Forest disease virus. Moreover, the compound strongly inhibited in vitro replication of West Nile virus, a typical mosquito-transmitted flavivirus. Two chemical forms of the compound, i.e. BCX4430 and BCX4430 hydrochloride, were compared and both exerted similar inhibitory profiles in our in vitro antiviral assay systems and no or negligible cytotoxicity in porcine kidney stable and Vero cells. The obtained data indicate that, in addition to mosquito-borne flaviviruses, the compound has strong antiviral activity against members of the TBEV serocomplex. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. In vitro characterization of the antiviral activity of fucoidan from Cladosiphon okamuranus against Newcastle Disease Virus

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    Elizondo-Gonzalez Regina

    2012-12-01

    Full Text Available Abstract Background Newcastle Disease Virus (NDV causes a serious infectious disease in birds that results in severe losses in the worldwide poultry industry. Despite vaccination, NDV outbreaks have increased the necessity of alternative prevention and control measures. Several recent studies focused on antiviral compounds obtained from natural resources. Many extracts from marine organisms have been isolated and tested for pharmacological purposes, and their antiviral activity has been demonstrated in vitro and in vivo. Fucoidan is a sulfated polysaccharide present in the cell wall matrix of brown algae that has been demonstrated to inhibit certain enveloped viruses with low toxicity. This study evaluated the potential antiviral activity and the mechanism of action of fucoidan from Cladosiphon okamuranus against NDV in the Vero cell line. Methods The cytotoxicity of fucoidan was determined by the MTT assay. To study its antiviral activity, fusion and plaque-forming unit (PFU inhibition assays were conducted. The mechanism of action was determined by time of addition, fusion inhibition, and penetration assays. The NDV vaccine strain (La Sota was used in the fusion inhibition assays. PFU and Western blot experiments were performed using a wild-type lentogenic NDV strain. Results Fucoidan exhibited antiviral activity against NDV La Sota, with an obtained IS50 >2000. In time of addition studies, we observed viral inhibition in the early stages of infection (0–60 min post-infection. The inhibition of viral penetration experiments with a wild-type NDV strain supported this result, as these experiments demonstrated a 48% decrease in viral infection as well as reduced HN protein expression. Ribavirin, which was used as an antiviral control, exhibited lower antiviral activity than fucoidan and high toxicity at active doses. In the fusion assays, the number of syncytia was significantly reduced (70% inhibition when fucoidan was added before cleavage of

  15. Long-term use of first-line highly active antiretroviral therapy is not associated with carotid artery stiffness in human immunodeficiency virus-positive patients

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    Haohui Zhu

    2014-09-01

    Conclusion: The first-line highly active antiretroviral therapy currently used in China is not associated with carotid artery stiffness in human immunodeficiency virus-positive patients with good highly active antiretroviral therapy compliance. Human immunodeficiency virus may play a role in the development of atherosclerosis.

  16. Novel roles for well-known players: from tobacco mosaic virus pests to enzymatically active assemblies

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    Claudia Koch

    2016-04-01

    Full Text Available The rod-shaped nanoparticles of the widespread plant pathogen tobacco mosaic virus (TMV have been a matter of intense debates and cutting-edge research for more than a hundred years. During the late 19th century, their behavior in filtration tests applied to the agent causing the 'plant mosaic disease' eventually led to the discrimination of viruses from bacteria. Thereafter, they promoted the development of biophysical cornerstone techniques such as electron microscopy and ultracentrifugation. Since the 1950s, the robust, helically arranged nucleoprotein complexes consisting of a single RNA and more than 2100 identical coat protein subunits have enabled molecular studies which have pioneered the understanding of viral replication and self-assembly, and elucidated major aspects of virus–host interplay, which can lead to agronomically relevant diseases. However, during the last decades, TMV has acquired a new reputation as a well-defined high-yield nanotemplate with multivalent protein surfaces, allowing for an ordered high-density presentation of multiple active molecules or synthetic compounds. Amino acid side chains exposed on the viral coat may be tailored genetically or biochemically to meet the demands for selective conjugation reactions, or to directly engineer novel functionality on TMV-derived nanosticks. The natural TMV size (length: 300 nm in combination with functional ligands such as peptides, enzymes, dyes, drugs or inorganic materials is advantageous for applications ranging from biomedical imaging and therapy approaches over surface enlargement of battery electrodes to the immobilization of enzymes. TMV building blocks are also amenable to external control of in vitro assembly and re-organization into technically expedient new shapes or arrays, which bears a unique potential for the development of 'smart' functional 3D structures. Among those, materials designed for enzyme-based biodetection layouts, which are routinely applied

  17. Regulation of ROS in transmissible gastroenteritis virus-activated apoptotic signaling

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Li [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China); College of Life Sciences, Hainan Normal University, Haikou, Hainan 571158 (China); Zhao, Xiaomin; Huang, Yong; Du, Qian; Dong, Feng; Zhang, Hongling; Song, Xiangjun; Zhang, Wenlong [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China); Tong, Dewen, E-mail: dwtong@nwsuaf.edu.cn [College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100 (China)

    2013-12-06

    Highlights: •TGEV infection induced ROS accumulation. •ROS accumulation is involved in TGEV-induced mitochondrial integrity impairment. •ROS is associated with p53 activation and apoptosis occurrence in TGEV-infected cells. -- Abstract: Transmissible gastroenteritis virus (TGEV), an enteropathogenic coronavirus, causes severe lethal watery diarrhea and dehydration in piglets. Previous studies indicate that TGEV infection induces cell apoptosis in host cells. In this study, we investigated the roles and regulation of reactive oxygen species (ROS) in TGEV-activated apoptotic signaling. The results showed that TGEV infection induced ROS accumulation, whereas UV-irradiated TGEV did not promote ROS accumulation. In addition, TGEV infection lowered mitochondrial transmembrane potential in PK-15 cell line, which could be inhibited by ROS scavengers, pyrrolidinedithiocarbamic (PDTC) and N-acetyl-L-cysteine (NAC). Furthermore, the two scavengers significantly inhibited the activation of p38 MAPK and p53 and further blocked apoptosis occurrence through suppressing the TGEV-induced Bcl-2 reduction, Bax redistribution, cytochrome c release and caspase-3 activation. These results suggest that oxidative stress pathway might be a key element in TGEV-induced apoptosis and TGEV pathogenesis.

  18. Antiviral activity of ovine interferon tau 4 against foot-and-mouth disease virus.

    Science.gov (United States)

    Usharani, Jayaramaiah; Park, Sun Young; Cho, Eun-Ju; Kim, Chungsu; Ko, Young-Joon; Tark, Dongseob; Kim, Su-Mi; Park, Jong-Hyeon; Lee, Kwang-Nyeong; Lee, Myoung-Heon; Lee, Hyang-Sim

    2017-07-01

    Foot-and-mouth disease (FMD) is an economically important disease in most parts of the world and new therapeutic agents are needed to protect the animals before vaccination can trigger the host immune response. Although several interferons have been used for their antiviral activities against Foot-and-mouth disease virus (FMDV), ovine interferon tau 4 (OvIFN-τ4), with a broad-spectrum of action, cross-species antiviral activity, and lower incidence of toxicity in comparison to other type І interferons, has not yet been evaluated for this indication. This is the first study to evaluate the antiviral activity of OvIFN-τ4 against various strains of FMDV. The effective anti-cytopathic concentration of OvIFN-τ4 and its effectiveness pre- and post-infection with FMDV were tested in vitro in LFBK cells. In vivo activity of OvIFN-τ4 was then confirmed in a mouse model of infection. OvIFN-τ4 at a concentration of 500 ng, protected mice until 5days post-FMDV challenge and provided 90% protection for 10 days following FMDV challenge. These results suggest that OvIFN-τ4 could be used as an alternative to other interferons or antiviral agents at the time of FMD outbreak. Copyright © 2017. Published by Elsevier B.V.

  19. Cissampelos pareira Linn: Natural Source of Potent Antiviral Activity against All Four Dengue Virus Serotypes.

    Science.gov (United States)

    Sood, Ruchi; Raut, Rajendra; Tyagi, Poornima; Pareek, Pawan Kumar; Barman, Tarani Kanta; Singhal, Smita; Shirumalla, Raj Kumar; Kanoje, Vijay; Subbarayan, Ramesh; Rajerethinam, Ravisankar; Sharma, Navin; Kanaujia, Anil; Shukla, Gyanesh; Gupta, Y K; Katiyar, Chandra K; Bhatnagar, Pradip K; Upadhyay, Dilip J; Swaminathan, Sathyamangalam; Khanna, Navin

    2015-12-01

    Dengue, a mosquito-borne viral disease, poses a significant global public health risk. In tropical countries such as India where periodic dengue outbreaks can be correlated to the high prevalence of the mosquito vector, circulation of all four dengue viruses (DENVs) and the high population density, a drug for dengue is being increasingly recognized as an unmet public health need. Using the knowledge of traditional Indian medicine, Ayurveda, we developed a systematic bioassay-guided screening approach to explore the indigenous herbal bio-resource to identify plants with pan-DENV inhibitory activity. Our results show that the alcoholic extract of Cissampelos pariera Linn (Cipa extract) was a potent inhibitor of all four DENVs in cell-based assays, assessed in terms of viral NS1 antigen secretion using ELISA, as well as viral replication, based on plaque assays. Virus yield reduction assays showed that Cipa extract could decrease viral titers by an order of magnitude. The extract conferred statistically significant protection against DENV infection using the AG129 mouse model. A preliminary evaluation of the clinical relevance of Cipa extract showed that it had no adverse effects on platelet counts and RBC viability. In addition to inherent antipyretic activity in Wistar rats, it possessed the ability to down-regulate the production of TNF-α, a cytokine implicated in severe dengue disease. Importantly, it showed no evidence of toxicity in Wistar rats, when administered at doses as high as 2g/Kg body weight for up to 1 week. Our findings above, taken in the context of the human safety of Cipa, based on its use in Indian traditional medicine, warrant further work to explore Cipa as a source for the development of an inexpensive herbal formulation for dengue therapy. This may be of practical relevance to a dengue-endemic resource-poor country such as India.

  20. Protocatechuic acid, a novel active substance against avian influenza virus H9N2 infection.

    Directory of Open Access Journals (Sweden)

    Changbo Ou

    Full Text Available Influenza virus H9N2 subtype has triggered co-infection with other infectious agents, resulting in huge economical losses in the poultry industry. Our current study aims to evaluate the antiviral activity of protocatechuic acid (PCA against a virulent H9N2 strain in a mouse model. 120 BALB/c mice were divided into one control group, one untreated group, one 50 mg/kg amantadine hydrochloride-treated group and three PCA groups treated 12 hours post-inoculation with 40, 20 or 10 mg/kg PCA for 7 days. All the infected animals were inoculated intranasally with 0.2 ml of a A/Chicken/Hebei/4/2008(H9N2 inoculum. A significant body weight loss was found in the 20 mg/kg and 40 mg/kg PCA-treated and amantadine groups as compared to the control group. The 14 day survivals were 94.4%, 100% and 95% in the PCA-treated groups and 94.4% in the amantadine hydrochloride group, compared to less than 60% in the untreated group. Virus loads were less in the PCA-treated groups compared to the amantadine-treated or the untreated groups. Neutrophil cells in BALF were significantly decreased while IFN-γ, IL-2, TNF-α and IL-6 decreased significantly at days 7 in the PCA-treated groups compared to the untreated group. Furthermore, a significantly decreased CD4+/CD8+ ratio and an increased proportion of CD19 cells were observed in the PCA-treated groups and amantadine-treated group compared to the untreated group. Mice administered with PCA exhibited a higher survival rate and greater viral clearance associated with an inhibition of inflammatory cytokines and activation of CD8+ T cell subsets. PCA is a promising novel agent against bird flu infection in the poultry industry.

  1. The X protein of hepatitis B virus activates hepatoma cell proliferation through repressing melanoma inhibitory activity 2 gene

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yilin; Yang, Yang; Cai, Yanyan; Liu, Fang; Liu, Yingle; Zhu, Ying [State Key Laboratory of Virology, College of Life Sciences, and Chinese-French Liver Disease Research Institute at Zhongnan Hospital, Wuhan University, Wuhan 430072 (China); Wu, Jianguo, E-mail: jwu@whu.edu.cn [State Key Laboratory of Virology, College of Life Sciences, and Chinese-French Liver Disease Research Institute at Zhongnan Hospital, Wuhan University, Wuhan 430072 (China)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer We demonstrated that HBV represses MIA2 gene expression both invitro and in vivo. Black-Right-Pointing-Pointer The X protein of HBV plays a major role in such regulation. Black-Right-Pointing-Pointer Knock-down of MIA2 in HepG2 cells activates cell growth and proliferation. Black-Right-Pointing-Pointer HBx activates cell proliferation, over-expression of MIA2 impaired such regulation. Black-Right-Pointing-Pointer HBx activates hepatoma cell proliferation through repressing MIA2 expression. -- Abstract: Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer deaths globally. Chronic hepatitis B virus (HBV) infection accounts for over 75% of all HCC cases; however, the molecular pathogenesis of HCC is not well understood. In this study, we found that the expression of the newly identified gene melanoma inhibitory activity 2 (MIA2) was reduced by HBV infection invitro and invivo, and that HBV X protein (HBx) plays a major role in this regulation. Recent studies have revealed that MIA2 is a potential tumor suppressor, and that, in most HCCs, MIA2 expression is down-regulated or lost. We found that the knock-down of MIA2 in HepG2 cells activated cell growth and proliferation, suggesting that MIA2 inhibits HCC cell growth and proliferation. In addition, the over-expression of HBx alone induced cell proliferation, whereas MIA2 over-expression impaired the HBx-mediated induction of proliferation. Taken together, our results suggest that HBx activates hepatoma cell growth and proliferation through repression of the potential tumor suppressor MIA2.

  2. The X protein of hepatitis B virus activates hepatoma cell proliferation through repressing melanoma inhibitory activity 2 gene

    International Nuclear Information System (INIS)

    Xu, Yilin; Yang, Yang; Cai, Yanyan; Liu, Fang; Liu, Yingle; Zhu, Ying; Wu, Jianguo

    2011-01-01

    Highlights: ► We demonstrated that HBV represses MIA2 gene expression both invitro and in vivo. ► The X protein of HBV plays a major role in such regulation. ► Knock-down of MIA2 in HepG2 cells activates cell growth and proliferation. ► HBx activates cell proliferation, over-expression of MIA2 impaired such regulation. ► HBx activates hepatoma cell proliferation through repressing MIA2 expression. -- Abstract: Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer deaths globally. Chronic hepatitis B virus (HBV) infection accounts for over 75% of all HCC cases; however, the molecular pathogenesis of HCC is not well understood. In this study, we found that the expression of the newly identified gene melanoma inhibitory activity 2 (MIA2) was reduced by HBV infection invitro and invivo, and that HBV X protein (HBx) plays a major role in this regulation. Recent studies have revealed that MIA2 is a potential tumor suppressor, and that, in most HCCs, MIA2 expression is down-regulated or lost. We found that the knock-down of MIA2 in HepG2 cells activated cell growth and proliferation, suggesting that MIA2 inhibits HCC cell growth and proliferation. In addition, the over-expression of HBx alone induced cell proliferation, whereas MIA2 over-expression impaired the HBx-mediated induction of proliferation. Taken together, our results suggest that HBx activates hepatoma cell growth and proliferation through repression of the potential tumor suppressor MIA2.

  3. Canine Distemper Virus Fusion Activation: Critical Role of Residue E123 of CD150/SLAM.

    Science.gov (United States)

    Khosravi, Mojtaba; Bringolf, Fanny; Röthlisberger, Silvan; Bieringer, Maria; Schneider-Schaulies, Jürgen; Zurbriggen, Andreas; Origgi, Francesco; Plattet, Philippe

    2016-02-01

    Measles virus (MeV) and canine distemper virus (CDV) possess tetrameric attachment proteins (H) and trimeric fusion proteins, which cooperate with either SLAM or nectin 4 receptors to trigger membrane fusion for cell entry. While the MeV H-SLAM cocrystal structure revealed the binding interface, two distinct oligomeric H assemblies were also determined. In one of the conformations, two SLAM units were sandwiched between two discrete H head domains, thus spotlighting two binding interfaces ("front" and "back"). Here, we investigated the functional relevance of both interfaces in activating the CDV membrane fusion machinery. While alanine-scanning mutagenesis identified five critical regulatory residues in the front H-binding site of SLAM, the replacement of a conserved glutamate residue (E at position 123, replaced with A [E123A]) led to the most pronounced impact on fusion promotion. Intriguingly, while determination of the interaction of H with the receptor using soluble constructs revealed reduced binding for the identified SLAM mutants, no effect was recorded when physical interaction was investigated with the full-length counterparts of both molecules. Conversely, although mutagenesis of three strategically selected residues within the back H-binding site of SLAM did not substantially affect fusion triggering, nevertheless, the mutants weakened the H-SLAM interaction recorded with the membrane-anchored protein constructs. Collectively, our findings support a mode of binding between the attachment protein and the V domain of SLAM that is common to all morbilliviruses and suggest a major role of the SLAM residue E123, located at the front H-binding site, in triggering the fusion machinery. However, our data additionally support the hypothesis that other microdomain(s) of both glycoproteins (including the back H-binding site) might be required to achieve fully productive H-SLAM interactions. A complete understanding of the measles virus and canine distemper virus

  4. Activation of human T cells by a tumor vaccine infected with recombinant Newcastle disease virus producing IL-2

    NARCIS (Netherlands)

    Janke, M.; Peeters, B.; Zhao, H.; Leeuw, O.; Moormann, R.J.M.; Arnold, A.; Ziouta, Y.; Fournier, P.; Schirrmacher, V.

    2008-01-01

    A new recombinant (rec) Newcastle disease virus (NDV) with incorporated human interleukin 2 (IL-2) as foreign therapeutic gene [rec(IL-2)] will be described. The foreign gene in rec(IL-2) did not affect the main features of NDV replication nor its tumor selectivity. Biologically active IL-2 was

  5. Tumor Necrosis Factor-Mediated Survival of CD169+ Cells Promotes Immune Activation during Vesicular Stomatitis Virus Infection

    DEFF Research Database (Denmark)

    Shinde, Prashant V; Xu, Haifeng C; Maney, Sathish Kumar

    2018-01-01

    Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169(+) cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169(+) cells during viral infections remain ...

  6. Monomeric nucleoprotein of influenza A virus.

    Directory of Open Access Journals (Sweden)

    Sylvie Chenavas

    2013-03-01

    Full Text Available Isolated influenza A virus nucleoprotein exists in an equilibrium between monomers and trimers. Samples containing only monomers or only trimers can be stabilized by respectively low and high salt. The trimers bind RNA with high affinity but remain trimmers, whereas the monomers polymerise onto RNA forming nucleoprotein-RNA complexes. When wild type (wt nucleoprotein is crystallized, it forms trimers, whether one starts with monomers or trimers. We therefore crystallized the obligate monomeric R416A mutant nucleoprotein and observed how the domain exchange loop that leads over to a neighbouring protomer in the trimer structure interacts with equivalent sites on the mutant monomer surface, avoiding polymerisation. The C-terminus of the monomer is bound to the side of the RNA binding surface, lowering its positive charge. Biophysical characterization of the mutant and wild type monomeric proteins gives the same results, suggesting that the exchange domain is folded in the same way for the wild type protein. In a search for how monomeric wt nucleoprotein may be stabilized in the infected cell we determined the phosphorylation sites on nucleoprotein isolated from virus particles. We found that serine 165 was phosphorylated and conserved in all influenza A and B viruses. The S165D mutant that mimics phosphorylation is monomeric and displays a lowered affinity for RNA compared with wt monomeric NP. This suggests that phosphorylation may regulate the polymerisation state and RNA binding of nucleoprotein in the infected cell. The monomer structure could be used for finding new anti influenza drugs because compounds that stabilize the monomer may slow down viral infection.

  7. Dryocrassin ABBA, a novel active substance for use against amantadine-resistance H5N1 avian Influenza virus

    Directory of Open Access Journals (Sweden)

    Changbo Ou

    2015-06-01

    Full Text Available The occurrence of multi-drug resistant highly pathogenic avian influenza virus (HPAIV strains highlights the urgent need for strategies for the prevention and control of avian influenza virus. The aim of our current study is to evaluate the antiviral activity of dryocrassin ABBA isolated from Rhizoma Dryopteridis Crassirhizomatis (RDC against an amantadine-resistant H5N1 (A/Chicken/Hebei/706/2005 strain in a mouse model. Post inoculation with HPAIV H5N1 virus in mice, the survival rate was 87%, 80% and 60% respectively in the 33mg/kg, 18mg/kg and 12.5 mg/kg Dryocrassin ABBA-treated groups. On the other hand, the survival rate was 53% and 20%, respectively in the amantadine-treated group and untreated group. Mice administered dryocrassin ABBA or amantadine showed a significant weight increase compared to the untreated group. Moreover, 33 mg/kg and 18 mg/kg dryocrassin ABBA have decreased lung index (P>0.05 and virus loads (P<0.01 compared to the untreated group on day 7. Also, on day 7 bronchoalveolar lavage fluid pro-inflammatory cytokines (IL-6, TNF-α and IFN-γ decreased significantly (P<0.01 while anti-inflammatory cytokines (IL-10 and MCP-1 were increased significantly (P<0.01 in the 33 mg/kg and 18 mg/kg dryocrassin ABBA-treated groups compared to the amantadine group and the untreated group. Moreover, the concentrations of IL-12 in drug-treated groups were significantly (P<0.01 lowered compared with the untreated group. Based on the above we conclude that orally administered dryocrassin ABBA provided mice protection against avian influenza virus H5N1 by inhibiting inflammation and reducing virus loads. Dryocrassin ABBA is a potential novel lead compound which had antiviral effects on amantadine-resistant avian influenza virus H5N1 infection.

  8. Immunogenicity and tolerability of inactivated flu vaccine In high risk and healthy children Inmunogenicidad y tolerancia de la vacuna inactivada anti-influenza en niños en alto riesgo y en controles sanos

    Directory of Open Access Journals (Sweden)

    Maria Luisa Avila Aguero

    2007-08-01

    Full Text Available We conducted this open study to evaluate the immunogenicity and safety of the inactivated influenza vaccine, Imovax Gripe® in 154 children between 6 and 36 months of age at high risk of influenza- related complications, and in a reference group of 64 healthy children. The study was conducted over two flu seasons, in which the vaccine contained the same A strains but different B strains. The results for the A/H3N2 and A/H1N1 strains from the two flu seasons were pooled, but those for the B strains were not. Anti-hemagglutinin (HA antibody titers were determined before, and one month after each vaccination, and safety was evaluated based on diary card reporting any adverse event observed, either included or not in the list of "solicited events". Within each group of vaccines, the seroconversion rates, seroprotection rates, and ratio of post- to prevaccination geometric mean titers (GMTR for the A/H3N2 and the A/H1N1 strains fulfilled all requirements of the criteria of the European Union Committee for Proprietary Medicinal Products (CPMP. The immune responses in high-risk and in healthy children were similar, and consistent with those observed in previous studies conducted in healthy children. The vaccine was equally well tolerated by all study groups. Reactogenicity was low and similar in both high-risk and healthy children. Overall from 9.5% to 15.4% of at-risk children and 12% of healthy children reported a solicited local reaction; 23.0 to 28.8% of high-risk and 25.3% of healthy children reported a solicited systemic reaction. The study results provide support for vaccination of children at high-risk of influenza related complications.Se realizó un estudio clínico abierto para evaluar la inmunogenícidad y la seguridad de la vacuna inactivada anti-influenza, Imovax Gripe®, en 154 niños entre 6 y 36 meses de edad con alto riesgo de complicaciones ligadas a la influenza, y en un grupo de referencia de 64 niños sanos. El estudio fue

  9. Effect of Human Immunodeficiency Virus Infection on Plasma Bactericidal Activity against Salmonella enterica Serovar Typhimurium

    Science.gov (United States)

    Trebicka, Estela; Shanmugam, Nanda Kumar N.; Mikhailova, Anastassia; Alter, Galit

    2014-01-01

    Individuals with human immunodeficiency virus (HIV) infection have increased susceptibility to invasive disease caused by Salmonella enterica serovar Typhimurium. Studies from Africa have suggested that this susceptibility is related in part to the development of a high level of lipopolysaccharide (LPS)-specific IgG that is able to inhibit the killing of S. Typhimurium by bactericidal antibodies in healthy individuals. To explore this issue further, we examined the bactericidal activity against S. Typhimurium using serum and plasma samples from healthy controls and various clinical subgroups of HIV-infected adults in the United States. We found that the bactericidal activity in the samples from HIV-positive elite controllers was comparable to that from healthy individuals, whereas it was significantly reduced in HIV-positive viremic controllers and untreated chronic progressors. As demonstrated previously for healthy controls, the bactericidal activity of the plasma from the elite controllers was inhibited by preincubation with S. Typhimurium LPS, suggesting that it was mediated by anti-LPS antibodies. S. Typhimurium LPS-specific IgG was significantly reduced in all subgroups of HIV-infected individuals. Interestingly, and in contrast to the healthy controls, plasma from all HIV-positive subgroups inhibited in vitro killing of S. Typhimurium by plasma from a healthy individual. Our results, together with the findings from Africa, suggest that multiple mechanisms may be involved in the HIV-induced dysregulation of humoral immunity to S. Typhimurium. PMID:25121777

  10. Telomerase Activity in Chicken EmbryoFibroblast Cell Cultures Infected withMarek's Disease Virus

    Directory of Open Access Journals (Sweden)

    Gregory A. Tannock

    2010-07-01

    Full Text Available Background:Telomerase is a ribonucleoprotein, which adds telomeric repeats onto the 3’end of existing telomers at the end of chromosomes ineukaryotes. One hypothesis states that telomere length may function as a mitoticclock, therefore expression of telomerase activity in cancer cells may be a necessary and essential step for tumor development and progression.Methods:The detectability of telomerase activity in chicken embryofibroblast (CEF cells infected with different passages of Marek's disease virus(MDV was tested with the TRAPEZE® telomerase detection kit at passages14 (P14, P80/1 and P120 for the Woodland strain, and passage 9 (P9 for theMPF57 strain. Results:The results showed increased telomerase activity in MDV Woodlands strain at P14 and MPF57 strain at P9. Conclusion:Our results suggest that MDV-transformed cells at low passage are a suitable system for the study of telomerases in tumor developmentand for testing telomerase-inhibiting drugs.

  11. Influence of immune activation and inflammatory response on cardiovascular risk associated with the human immunodeficiency virus

    Directory of Open Access Journals (Sweden)

    Beltrán LM

    2015-01-01

    Full Text Available Luis M Beltrán,1 Alfonso Rubio-Navarro,2 Juan Manuel Amaro-Villalobos,2 Jesús Egido,2–4 Juan García-Puig,1 Juan Antonio Moreno21Metabolic-Vascular Unit, Fundación IdiPAZ-Hospital Universitario La Paz, Madrid, Spain; 2Vascular, Renal, and Diabetes Research Lab, IIS-Fundación Jiménez Díaz, Madrid, Spain; 3Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM, Madrid, Spain; 4Fundación Renal Iñigo Alvarez de Toledo-Instituto Reina Sofía de Investigaciones Nefrológicas (FRIAT-IRSIN, Madrid, SpainAbstract: Patients infected with the human immunodeficiency virus (HIV have an increased cardiovascular risk. Although initially this increased risk was attributed to metabolic alterations associated with antiretroviral treatment, in recent years, the attention has been focused on the HIV disease itself. Inflammation, immune system activation, and endothelial dysfunction facilitated by HIV infection have been identified as key factors in the development and progression of atherosclerosis. In this review, we describe the epidemiology and pathogenesis of cardiovascular disease in patients with HIV infection and summarize the latest knowledge on the relationship between traditional and novel inflammatory, immune activation, and endothelial dysfunction biomarkers on the cardiovascular risk associated with HIV infection.Keywords: HIV, cardiovascular disease, immune activation, inflammation, antiretroviral therapy

  12. Active vaccination to prevent de novo hepatitis B virus infection in liver transplantation

    Science.gov (United States)

    Lin, Chih-Che; Yong, Chee-Chien; Chen, Chao-Long

    2015-01-01

    The shortage of organ donors mandates the use of liver allograft from anti-HBc(+) donors, especially in areas highly endemic for hepatitis B virus (HBV) infection. The incidence of de novo hepatitis B infection (DNH) is over 30%-70% among recipients of hepatitis B core antibody (HBcAb) (+) grafts without any prophylaxis after liver transplantation (LT). Systematic reviews showed that prophylactic therapy [lamivudine and/or hepatitits B immunoglobulin (HBIG)] dramatically reduces the probability of DNH. However, there are limited studies regarding the effects of active immunization to prevent DNH, and the role of active vaccination is not well-defined. This review focuses on the feasibility and efficacy of pre- and post-LT HBV vaccination to prevent DNH in HBsAg(-) recipient using HBcAb(+) grafts. The presence of HBsAb in combination with lamivudine or HBIG results in lower incidence of DNH and may reduce the requirement of HBIG. There was a trend towards decreasing incidence of DNH with higher titers of HBsAb. High titers of HBsAb (> 1000 IU/L) achieved after repeated vaccination could eliminate the necessity for additional antiviral prophylaxis in pediatric recipients. In summary, active vaccination with adequate HBsAb titer is a feasible, cost-effective strategy to prevent DNH in recipients of HBcAb(+) grafts. HBV vaccination is advised for candidates on waiting list and for recipients after withdrawal of steroids and onset of low dose immunosuppression after transplantation. PMID:26494965

  13. The role of myeloid cell activation and arginine metabolism in the pathogenesis of virus-induced diseases

    Directory of Open Access Journals (Sweden)

    Kristina S. Burrack

    2014-09-01

    Full Text Available When an antiviral immune response is generated, a balance must be reached between two opposing pathways: the production of proinflammatory and cytotoxic effectors that drive a robust antiviral immune response to control the infection and regulators that function to limit or blunt an excessive immune response to minimize immune-mediated pathology and repair tissue damage. Myeloid cells, including monocytes and macrophages, play an important role in this balance, particularly through the activities of the arginine-hydrolyzing enzymes nitric oxide synthase 2 (Nos2; iNOS and arginase 1 (Arg1. Nitric oxide (NO production by iNOS is an important proinflammatory mediator, whereas Arg1-expressing macrophages contribute to the resolution of inflammation and wound repair. In the context of viral infections, expression of these enzymes can result in a variety of outcomes for the host. NO has direct antiviral properties against some viruses, whereas during other virus infections NO can mediate immunopathology and/or inhibit the antiviral immune response to promote chronic infection. Arg1 activity has important wound healing functions but can also inhibit the antiviral immune response during some viral infections. Thus, depending on the specific virus and the tissue(s involved, the activity of both of these arginine-hydrolyzing enzymes can either exacerbate or limit the severity of virus-induced disease. In this review, we will discuss a variety of viral infections, including HIV, SARS-CoV, LCMV, HCV, RSV, and others, where myeloid cells influence the control and clearance of the virus from the host, as well as the severity and resolution of tissue damage, via the activities of iNOS and/or Arg1. Clearly, monocyte/macrophage activation and arginine metabolism will continue to be important areas of investigation in the context of viral infections.

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

    Science.gov (United States)

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

    2014-11-10

    Long-range enhancers of transcription are a key component of the genomic regulatory architecture. Recent studies have identified bi-directionally transcribed RNAs emanating from these enhancers known as eRNAs. However, it remains unclear how tightly coupled eRNA production is with enhancer activity. Through our systematic search for long-range elements that interact with the interferon-β gene, a model system for studying inducible transcription, we have identified a novel enhancer, which we have named L2 that regulates the expression of interferon-β. We have demonstrated its virus-inducible enhancer activity by analyzing epigenomic profiles, transcription factor association, nascent RNA production and activity in reporter assays. This enhancer exhibits intimately linked virus-inducible enhancer and bidirectional promoter activity that is largely dependent on a conserved Interferon Stimulated Response Element and robustly generates virus inducible eRNAs. Notably, its enhancer and promoter activities are fully retained in reporter assays even upon a complete elimination of its associated eRNA sequences. Finally, we show that L2 regulates IFNB1 expression by siRNA knockdown of eRNAs, and the deletion of L2 in a BAC transfection assay. Thus, L2 is a novel enhancer that regulates IFNB1 and whose eRNAs exert significant activity in vivo that is distinct from those activities recapitulated in the luciferase reporter assays. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. NMR structure of a biologically active peptide containing the RNA-binding domain of human immunodeficiency virus type 1 Tat.

    Science.gov (United States)

    Mujeeb, A; Bishop, K; Peterlin, B M; Turck, C; Parslow, T G; James, T L

    1994-01-01

    The Tat protein of human immunodeficiency virus type 1 enhances transcription by binding to a specific RNA element on nascent viral transcripts. Binding is mediated by a 10-amino acid basic domain that is rich in arginines and lysines. Here we report the three-dimensional peptide backbone structure of a biologically active 25-mer peptide that contains the human immunodeficiency virus type 1 Tat basic domain linked to the core regulatory domain of another lentiviral Tat--i.e., that from equine infectious anemia virus. Circular dichroism and two-dimensional proton NMR studies of this hybrid peptide indicate that the Tat basic domain forms a stable alpha-helix, whereas the adjacent regulatory sequence is mostly in extended form. These findings suggest that the tendency to form stable alpha-helices may be a common property of arginine- and lysine-rich RNA-binding domains. Images PMID:8058789

  16. Transmissible Gastroenteritis Virus Papain-Like Protease 1 Antagonizes Production of Interferon-βthrough Its Deubiquitinase Activity.

    Science.gov (United States)

    Hu, Xiaoliang; Tian, Jin; Kang, Hongtao; Guo, Dongchun; Liu, Jiasen; Liu, Dafei; Jiang, Qian; Li, Zhijie; Qu, Juanjuan; Qu, Liandong

    2017-01-01

    Coronaviruses (CoVs), such as human coronavirus NL63 (HCoV-NL63), severe acute respiratory syndrome CoV (SARS-CoV), murine hepatitis virus (MHV), porcine epidemic diarrhea virus (PEDV), and Middle East Respiratory Syndrome Coronavirus (MERS-CoV), encode papain-like (PL) proteases that inhibit Sendai virus- (SeV-) induced interferon (IFN- β ) production. Recently, the crystal structure of transmissible gastroenteritis virus (TGEV) PL1 has been solved, which was similar to that of SARS-CoV PL2 pro , which may antagonize host innate immunity. However, very little is known about whether TGEV PL1 can antagonize host innate immune response. Here, we presented evidence that TGEV PL1 encoded by the replicase gene could suppress the IFN- β expression and inhibit the nuclear translocation of interferon regulatory factor 3 (IRF3). The ability to antagonize IFN- β production was dependent on the intact catalytic activity of PL1. Furthermore, TGEV PL1 exerted deubiquitinase (DUB) activity which strongly inhibited the retinoic acid-induced gene I- (RIG-1-) and stimulator of interferon gene- (STING-) dependent IFN expression. Our data collectively suggest that TGEV PL1 can inhibit the IFN- β expression and interfere with RIG-1- and STING-mediated signaling through a viral DUB activity. Our study has yielded strong evidence for the TGEV PL1 mechanisms that counteract the host innate immunity.

  17. Transmissible Gastroenteritis Virus Papain-Like Protease 1 Antagonizes Production of Interferon-β through Its Deubiquitinase Activity

    Directory of Open Access Journals (Sweden)

    Xiaoliang Hu

    2017-01-01

    Full Text Available Coronaviruses (CoVs, such as human coronavirus NL63 (HCoV-NL63, severe acute respiratory syndrome CoV (SARS-CoV, murine hepatitis virus (MHV, porcine epidemic diarrhea virus (PEDV, and Middle East Respiratory Syndrome Coronavirus (MERS-CoV, encode papain-like (PL proteases that inhibit Sendai virus- (SeV- induced interferon (IFN-β production. Recently, the crystal structure of transmissible gastroenteritis virus (TGEV PL1 has been solved, which was similar to that of SARS-CoV PL2pro, which may antagonize host innate immunity. However, very little is known about whether TGEV PL1 can antagonize host innate immune response. Here, we presented evidence that TGEV PL1 encoded by the replicase gene could suppress the IFN-β expression and inhibit the nuclear translocation of interferon regulatory factor 3 (IRF3. The ability to antagonize IFN-β production was dependent on the intact catalytic activity of PL1. Furthermore, TGEV PL1 exerted deubiquitinase (DUB activity which strongly inhibited the retinoic acid-induced gene I- (RIG-1- and stimulator of interferon gene- (STING- dependent IFN expression. Our data collectively suggest that TGEV PL1 can inhibit the IFN-β expression and interfere with RIG-1- and STING-mediated signaling through a viral DUB activity. Our study has yielded strong evidence for the TGEV PL1 mechanisms that counteract the host innate immunity.

  18. A Whole Virus Pandemic Influenza H1N1 Vaccine Is Highly Immunogenic and Protective in Active Immunization and Passive Protection Mouse Models

    OpenAIRE

    Kistner, Otfried; Crowe, Brian A.; Wodal, Walter; Kerschbaum, Astrid; Savidis-Dacho, Helga; Sabarth, Nicolas; Falkner, Falko G.; Mayerhofer, Ines; Mundt, Wolfgang; Reiter, Manfred; Grillberger, Leopold; Tauer, Christa; Graninger, Michael; Sachslehner, Alois; Schwendinger, Michael

    2010-01-01

    The recent emergence and rapid spread of a novel swine-derived H1N1 influenza virus has resulted in the first influenza pandemic of this century. Monovalent vaccines have undergone preclinical and clinical development prior to initiation of mass immunization campaigns. We have carried out a series of immunogenicity and protection studies following active immunization of mice, which indicate that a whole virus, nonadjuvanted vaccine is immunogenic at low doses and protects against live virus c...

  19. Alpha 4 integrin directs virus-activated CD8+ T cells to sites of infection

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Andersson, E C; Scheynius, A

    1995-01-01

    This article examines the role of VLA-4 in directing lymphocytes to sites of viral infection using the murine lymphocytic choriomeningitis virus infection (LCMV) as the model system. This virus by itself induces little or no inflammation, but in most mouse/virus strain combinations a potent T cell...... response is induced, which is associated with marked CD8+ cell-mediated inflammation. Two expressions of LCMV-induced inflammation were studied: meningitis induced by intracerebral infection and adoptive transfer of virus-specific delayed-type hypersensitivity. Our previous studies have shown that LCMV...

  20. In vitro evaluation of novel antiviral activities of 60 medicinal plants extracts against hepatitis B virus.

    Science.gov (United States)

    Arbab, Ahmed Hassan; Parvez, Mohammad Khalid; Al-Dosari, Mohammed Salem; Al-Rehaily, Adnan Jathlan

    2017-07-01

    Currently, >35 Saudi Arabian medicinal plants are traditionally used for various liver disorders without a scientific rationale. This is the first experimental evaluation of the anti-hepatitis B virus (HBV) potential of the total ethanolic and sequential organic extracts of 60 candidate medicinal plants. The extracts were tested for toxicity on HepG2.2.15 cells and cytotoxicity concentration (CC 50 ) values were determined. The extracts were further investigated on HepG2.2.15 cells for anti-HBV activities by analyzing the inhibition of HBsAg and HBeAg production in the culture supernatants, and their half maximal inhibitory concentration (IC 50 ) and therapeutic index (TI) values were determined. Of the screened plants, Guiera senegalensis (dichloromethane extract, IC 50 =10.65), Pulicaria crispa (ethyl acetate extract, IC 50 =14.45), Coccinea grandis (total ethanol extract, IC 50 =31.57), Fumaria parviflora (hexane extract, IC 50 =35.44), Capparis decidua (aqueous extract, IC 50 =66.82), Corallocarpus epigeus (total ethanol extract, IC 50 =71.9), Indigofera caerulea (methanol extract, IC 50 =73.21), Abutilon figarianum (dichloromethane extract, IC 50 =99.76) and Acacia oerfota (total ethanol extract, IC 50 =101.46) demonstrated novel anti-HBV activities in a time- and dose-dependent manner. Further qualitative phytochemical analysis of the active extracts revealed the presence of alkaloids, tannins, flavonoids and saponins, which are attributed to antiviral efficacies. In conclusion, P. crispa, G. senegalensis and F. parviflora had the most promising anti-HBV potentials, including those of C. decidua , C. epigeus, A. figarianum , A. oerfota and I. caerulea with marked activities. However, a detailed phytochemical study of these extracts is essential to isolate the active principle(s) responsible for their novel anti-HBV potential.

  1. Antiviral Activity of Hatay Propolis Against Replication of Herpes Simplex Virus Type 1 and Type 2

    Science.gov (United States)

    Yildirim, Ayse; Duran, Gulay Gulbol; Duran, Nizami; Jenedi, Kemal; Bolgul, Behiye Sezgin; Miraloglu, Meral; Muz, Mustafa

    2016-01-01

    Background Propolis is a bee product widely used in folk medicine and possessing many pharmacological properties. In this study we aimed to investigate: i) the antiviral activities of Hatay propolis samples against HSV-1 and HSV-2 in HEp-2 cell line, and ii) the presence of the synergistic effects of propolis with acyclovir against these viruses. Material/Methods All experiments were carried out in HEp-2 cell cultures. Proliferation assays were performed in 24-well flat bottom microplates. We inoculated 1×105 cells per ml and RPMI 1640 medium with 10% fetal calf serum into each well. Studies to determine cytotoxic effect were performed. To investigate the presence of antiviral activity of propolis samples, different concentrations of propolis (3200, 1600, 800, 400, 200, 100, 75, 50, and 25 μg/mL) were added into the culture medium. The amplifications of HSV-1 and HSV-2 DNA were performed by real-time PCR method. Acyclovir (Sigma, USA) was chosen as a positive control. Cell morphology was evaluated by scanning electron microscopy (SEM). Results The replication of HSV-1 and HSV-2 was significantly suppressed in the presence of 25, 50, and 100 μg/mL of Hatay propolis. We found that propolis began to inhibit HSV-1 replication after 24 h of incubation and propolis activity against HSV-2 was found to start at 48 h following incubation. The activity of propolis against both HSV-1 and HSV-2 was confirmed by a significant decrease in the number of viral copies. Conclusions We determined that Hatay propolis samples have important antiviral effects compared with acyclovir. In particular, the synergy produced by antiviral activity of propolis and acyclovir combined had a stronger effect against HSV-1 and HSV-2 than acyclovir alone. PMID:26856414

  2. Supercritical fluid extraction of heather (Calluna vulgaris) and evaluation of anti-hepatitis C virus activity of the extracts

    OpenAIRE

    Rodríguez García-Risco, Mónica; Vázquez, Erika; Sheldon, Julie; Steinmann, Eike; Riebesehl, Nina; Fornari, Tiziana; Reglero, Guillermo

    2015-01-01

    Previous studies using lipid extracts of heather (Calluna vulgaris) leaves showed the presence of high concentrations of ursolic and oleanolic acid. These two compounds have been reported to present antiviral activity against hepatitis C virus (HCV). In this work, the supercritical fluid extraction of heather was studied with the aim of assessing a potential anti-HCV activity of the extracts owing to their triterpenic acid content. Supercritical extraction assays were carried out exploring th...

  3. Multi-Omics Studies towards Novel Modulators of Influenza A Virus–Host Interaction

    Directory of Open Access Journals (Sweden)

    Sandra Söderholm

    2016-09-01

    Full Text Available Human influenza A viruses (IAVs cause global pandemics and epidemics. These viruses evolve rapidly, making current treatment options ineffective. To identify novel modulators of IAV–host interactions, we re-analyzed our recent transcriptomics, metabolomics, proteomics, phosphoproteomics, and genomics/virtual ligand screening data. We identified 713 potential modulators targeting 199 cellular and two viral proteins. Anti-influenza activity for 48 of them has been reported previously, whereas the antiviral efficacy of the 665 remains unknown. Studying anti-influenza efficacy and immuno/neuro-modulating properties of these compounds and their combinations as well as potential viral and host resistance to them may lead to the discovery of novel modulators of IAV–host interactions, which might be more effective than the currently available anti-influenza therapeutics.

  4. Antiviral activity of Acacia nilotica against Hepatitis C Virus in liver infected cells

    Directory of Open Access Journals (Sweden)

    Javed Tariq

    2011-05-01

    Full Text Available Abstract Hepatitis C virus (HCV belonging to the family Flaviviridae has infected 3% of the population worldwide and 6% of the population in Pakistan. The only recommended standard treatment is pegylated INF-α plus ribavirin. Due to less compatibility of the standard treatment, thirteen medicinal plants were collected from different areas of Pakistan on the basis of undocumented antiviral reports against different viral infections. Medicinal plants were air dried, extracted and screened out against HCV by infecting HCV inoculums of 3a genotype in liver cells. RT-PCR results demonstrate that acetonic and methanolic extract of Acacia nilotica (AN showed more than 50% reduction at non toxic concentration. From the above results, it can be concluded that by selecting different molecular targets, specific structure-activity relationship can be achieved by doing mechanistic analysis. So, additional studies are required for the isolation and recognition of antiviral compound in AN to establish its importance as antiviral drug against HCV. For further research, we will scrutinize the synergistic effect of active antiviral compound in combination with standard PEG INF-α and ribavirin which may be helpful in exploring further gateways for antiviral therapy against HCV.

  5. Tannic acid modified silver nanoparticles show antiviral activity in herpes simplex virus type 2 infection.

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    Piotr Orlowski

    Full Text Available The interaction between silver nanoparticles and herpesviruses is attracting great interest due to their antiviral activity and possibility to use as microbicides for oral and anogenital herpes. In this work, we demonstrate that tannic acid modified silver nanoparticles sized 13 nm, 33 nm and 46 nm are capable of reducing HSV-2 infectivity both in vitro and in vivo. The antiviral activity of tannic acid modified silver nanoparticles was size-related, required direct interaction and blocked virus attachment, penetration and further spread. All tested tannic acid modified silver nanoparticles reduced both infection and inflammatory reaction in the mouse model of HSV-2 infection when used at infection or for a post-infection treatment. Smaller-sized nanoparticles induced production of cytokines and chemokines important for anti-viral response. The corresponding control buffers with tannic acid showed inferior antiviral effects in vitro and were ineffective in blocking in vivo infection. Our results show that tannic acid modified silver nanoparticles are good candidates for microbicides used in treatment of herpesvirus infections.

  6. Surface-Active Agents for Isolation of the Core Component of Avian Myeloblastosis Virus 1

    Science.gov (United States)

    Stromberg, Kurt

    1972-01-01

    Sixty-one surface-active agents were evaluated in a procedure designed to assess their ability to remove the envelope from the core component of avian myeloblastosis virus (AMV). The procedure consisted of centrifugation of intact AMV through a series of sucrose gradients each containing an upper layer of agent at one of eight concentrations between 0.01 and 10%. The effectiveness of an agent in producing AMV cores was indicated by (i) the appearance of light-scattering bands in the region of core buoyant density in gradient tubes; (ii) the range of surfactant concentration over which these bands appeared; and (iii) an electron microscopy assessment by the negative-staining technique of the relative proportion of core to non-core material in each of these bands. Six nonionic surfactants were selected by this screening method for comparison in regard to recovery of core protein and endogenous ribonucleic acid (RNA)-dependent deoxyribonucleic acid (DNA) polymerase activity, as well as further morphologic evaluation by electron microscopy. The nonionic surfactants of the polyoxyethylene alcohol class (particularly, Sterox SL) were most effective. Nonionic surfactants of the polyoxyethylene alkylphenol class (particularly, Nonidet P-40) were also effective. Sterox SL and Nonidet P-40 each gave a more than fivefold increase in specific activity of endogenous RNA-dependent DNA polymerase, and each gave a low recovery of core protein. Sterox SL did not interfere to the extent that Nonidet P-40 did in procedures which involved spectrophotometric assay at 260 nm. The use of Sterox SL resulted in the least envelope contamination of core preparations by electron microscopy examination, the most recovery of protein and endogenous RNA-dependent DNA polymerase activity, and a core buoyant density in sucrose of 1.27 g/ml. Images PMID:4112071

  7. Application of speckle image correlation for real-time assessment of metabolic activity in herpes virus-infected cells

    Science.gov (United States)

    Vladimirov, A. P.; Malygin, A. S.; Mikhailova, J. A.; Borodin, E. M.; Bakharev, A. A.; Poryvayeva, A. P.

    2014-09-01

    Earlier we reported developing a speckle interferometry technique and a device designed to assess the metabolic activity of a cell monolayer cultivated on a glass substrate. This paper aimed at upgrading the technique and studying its potential for real-time assessment of herpes virus development process. Speckle dynamics was recorded in the image plane of intact and virus-infected cell monolayer. HLE-3, L-41 and Vero cells were chosen as research targets. Herpes simplex virus-1-(HSV-1)- infected cell cultures were studied. For 24 h we recorded the digital value of optical signal I in one pixel and parameter η characterizing change in the distribution of the optical signal on 10 × 10-pixel areas. The coefficient of multiple determination calculated by η time dependences for three intact cell cultures equals 0.94. It was demonstrated that the activity parameters are significantly different for intact and virus-infected cells. The difference of η value for intact and HSV-1-infected cells is detectable 10 minutes from the experiment start.

  8. Application of speckle image correlation for real-time assessment of metabolic activity in herpes virus-infected cells

    International Nuclear Information System (INIS)

    Vladimirov, A P; Malygin, A S; Mikhailova, J A; Borodin, E M; Bakharev, A A; Poryvayeva, A P

    2014-01-01

    Earlier we reported developing a speckle interferometry technique and a device designed to assess the metabolic activity of a cell monolayer cultivated on a glass substrate. This paper aimed at upgrading the technique and studying its potential for real-time assessment of herpes virus development process. Speckle dynamics was recorded in the image plane of intact and virus-infected cell monolayer. HLE-3, L-41 and Vero cells were chosen as research targets. Herpes simplex virus-1-(HSV-1)- infected cell cultures were studied. For 24 h we recorded the digital value of optical signal I in one pixel and parameter η characterizing change in the distribution of the optical signal on 10 × 10-pixel areas. The coefficient of multiple determination calculated by η time dependences for three intact cell cultures equals 0.94. It was demonstrated that the activity parameters are significantly different for intact and virus-infected cells. The difference of η value for intact and HSV-1-infected cells is detectable 10 minutes from the experiment start.

  9. Antiviral properties of resveratrol against pseudorabies virus are associated with the inhibition of IκB kinase activation.

    Science.gov (United States)

    Zhao, Xinghong; Cui, Qiankun; Fu, Qiuting; Song, Xu; Jia, Renyong; Yang, Yi; Zou, Yuanfeng; Li, Lixia; He, Changliang; Liang, Xiaoxia; Yin, Lizi; Lin, Juchun; Ye, Gang; Shu, Gang; Zhao, Ling; Shi, Fei; Lv, Cheng; Yin, Zhongqiong

    2017-08-18

    Pseudorabies virus (PRV) is a pathogen of swine resulting in devastating disease and economic losses worldwide. Resveratrol (Res) exhibits inhibitory activity against a wide range of viruses. Despite these important advances, the molecular mechanism(s) by which Res exerts its broad biological effects have not yet been elucidated. In this paper, the antiviral activity of Res against PRV and its mechanism of action were investigated. The results showed that Res potently inhibited PRV replication in a dose-dependent manner, with a 50% inhibition concentration of 17.17 μM. The inhibition of virus multiplication in the presence of Res was not attributed to direct inactivation or inhibition of viral entry into the host cells but to the inhibition of viral multiplication in host cells. Further studies demonstrated that Res is a potent inhibitor of both NF-κB activation and NF-κB-dependent gene expression through its ability to inhibit IκB kinase activity, which is the key regulator in NF-κB activation. Thus, the inhibitory effect of Res on PRV-induced cell death and gene expression may be due to its ability to inhibit the degradation of IκB kinase. These results provided a new alternative control measure for PRV infection and new insights into the antiviral mechanism of Res.

  10. Active immunization in patients transplanted for hepatitis B virus related liver diseases: A prospective study.

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    Anli Yang

    Full Text Available Prophylactic administration of hepatitis B immunoglobulin (HBIG and nucleos(tide analogues (NAs is the standard treatment for controlling hepatitis B virus (HBV recurrence after liver transplantation (LT. Since lifelong use of HBIG is expensive and inconvenient and the antibodies level in anti-hepatitis B surface (HBs is not sustainable and stable, an alternative strategy is to produce anti-HBs antibodies by active immunization. Our present study aimed to prospectively investigate the efficacy and safety of procedural HBV vaccination in transplanted patients.Recipients who had undergone LT for hepatitis B related liver diseases more than one year before, with no evidence of HBV recurrence or rejection and normal liver function were enrolled. All subjects received the hepatitis B vaccine (40 μg by intramuscular injection at months 0, 1, 2, 6 and 12 after enrollment with continuous administration of NAs. The liver function and anti-HBs titers were measured before each vaccination and HBIG (400U was administrated intramuscularly when anti-HBs titer was lower than 30 IU/L during the course. The results of routine blood tests, liver function, concentration of immunosuppressant, and HBV-DNA copies were monitored during the research. After completion of the vaccination procedure, recipients were regarded as responders if their anti-HBs greater than 30 IU/L were maintained for up to six months without using HBIG and vaccine.Twenty-seven patients were enrolled in this study and the average anti-HBs titer before vaccination was 19.86±14.80 IU/L. The average anti-HBs titer of the nine responders at the end of the follow-up was 57.14±22.75 IU/L, giving an overall response rate of 33.3% (9/27. There were no reports of reactivation of HBV, rejection, severe anaphylaxis or other adverse events. Responders and non-responders showed their significant difference in anti-HBs titers after the fourth vaccination (P15 while most responders (8/9, 88.89% had low LY

  11. Active immunization in patients transplanted for hepatitis B virus related liver diseases: A prospective study.

    Science.gov (United States)

    Yang, Anli; Guo, Zhiyong; Ren, Qingqi; Wu, Linwei; Ma, Yi; Hu, Anbin; Wang, Dongping; Ye, Haidan; Zhu, Xiaofeng; Ju, Weiqiang; He, Xiaoshun

    2017-01-01

    Prophylactic administration of hepatitis B immunoglobulin (HBIG) and nucleos(t)ide analogues (NAs) is the standard treatment for controlling hepatitis B virus (HBV) recurrence after liver transplantation (LT). Since lifelong use of HBIG is expensive and inconvenient and the antibodies level in anti-hepatitis B surface (HBs) is not sustainable and stable, an alternative strategy is to produce anti-HBs antibodies by active immunization. Our present study aimed to prospectively investigate the efficacy and safety of procedural HBV vaccination in transplanted patients. Recipients who had undergone LT for hepatitis B related liver diseases more than one year before, with no evidence of HBV recurrence or rejection and normal liver function were enrolled. All subjects received the hepatitis B vaccine (40 μg) by intramuscular injection at months 0, 1, 2, 6 and 12 after enrollment with continuous administration of NAs. The liver function and anti-HBs titers were measured before each vaccination and HBIG (400U) was administrated intramuscularly when anti-HBs titer was lower than 30 IU/L during the course. The results of routine blood tests, liver function, concentration of immunosuppressant, and HBV-DNA copies were monitored during the research. After completion of the vaccination procedure, recipients were regarded as responders if their anti-HBs greater than 30 IU/L were maintained for up to six months without using HBIG and vaccine. Twenty-seven patients were enrolled in this study and the average anti-HBs titer before vaccination was 19.86±14.80 IU/L. The average anti-HBs titer of the nine responders at the end of the follow-up was 57.14±22.75 IU/L, giving an overall response rate of 33.3% (9/27). There were no reports of reactivation of HBV, rejection, severe anaphylaxis or other adverse events. Responders and non-responders showed their significant difference in anti-HBs titers after the fourth vaccination (P15) while most responders (8/9, 88.89%) had low LY

  12. Zika virus induces inflammasome activation in the glial cell line U87-MG.

    Science.gov (United States)

    Tricarico, Paola Maura; Caracciolo, Ilaria; Crovella, Sergio; D'Agaro, Pierlanfranco

    2017-10-28

    In the last years, neurological complications related to Zika virus (ZIKV) infection have emerged as an important threat to public health worldwide. ZIKV infection has been associated to neurological disorders such as congenital microcephaly in newborns and Guillain-Barré syndrome, myelopathy and encephalitis in adults. ZIKV is characterized by neurotropism and neurovirulence. Several studies have identified microglial nodules, gliosis, neuronal and glial cells degeneration and necrosis in the brain of ZIKV infected infants, suggesting that ZIKV could play a role in these neurological disorders through neuroinflammation and microglial activation. Little information is available about neuroinflammation and ZIKV-related neurological disorders. Therefore, we investigated if ZIKV is able to infect a glial cell line (U87-MG) and how the glial cell line responds to this infection in terms of inflammation (IL-1β, NLRP-3 and CASP-1), oxidative stress (SOD2 and HemeOX) and cell death. We observed a significant increase of ZIKV load in both cells and supernatants after 72 h, compared to 48 h of infection. We found that ZIKV infection induces an increase of IL-1β, NLRP-3 and CASP-1 genes expression. Significant increase of IL-1β and unchanged pro-IL-1β protein levels have also been detected. Moreover, we observed SOD2 and HemeOX increased gene expression mainly after 72 h post ZIKV infection. Subsequently, we found a decrease of U87-MG cell viability, after both 48 h and 72 h of ZIKV infection. Our results show that U87-MG cells are susceptible to ZIKV infection. ZIKV is able to successfully replicate in infected cells causing oxidative stress, NLRP3 inflammasome activation and subsequent release of mature IL-1β; this process culminates in cell death. Thus, considering the central role of neuroinflammation in neurological disorders, it is important to comprehend every aspect of this mechanism in order to better understand the pathogenesis of ZIKV infection and to

  13. Discovery of a novel compound with anti-venezuelan equine encephalitis virus activity that targets the nonstructural protein 2.

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    Dong-Hoon Chung

    2014-06-01

    Full Text Available Alphaviruses present serious health threats as emerging and re-emerging viruses. Venezuelan equine encephalitis virus (VEEV, a New World alphavirus, can cause encephalitis in humans and horses, but there are no therapeutics for treatment. To date, compounds reported as anti-VEEV or anti-alphavirus inhibitors have shown moderate activity. To discover new classes of anti-VEEV inhibitors with novel viral targets, we used a high-throughput screen based on the measurement of cell protection from live VEEV TC-83-induced cytopathic effect to screen a 340,000 compound library. Of those, we identified five novel anti-VEEV compounds and chose a quinazolinone compound, CID15997213 (IC50 = 0.84 µM, for further characterization. The antiviral effect of CID15997213 was alphavirus-specific, inhibiting VEEV and Western equine encephalitis virus, but not Eastern equine encephalitis virus. In vitro assays confirmed inhibition of viral RNA, protein, and progeny synthesis. No antiviral activity was detected against a select group of RNA viruses. We found mutations conferring the resistance to the compound in the N-terminal domain of nsP2 and confirmed the target residues using a reverse genetic approach. Time of addition studies showed that the compound inhibits the middle stage of replication when viral genome replication is most active. In mice, the compound showed complete protection from lethal VEEV disease at 50 mg/kg/day. Collectively, these results reveal a potent anti-VEEV compound that uniquely targets the viral nsP2 N-terminal domain. While the function of nsP2 has yet to be characterized, our studies suggest that the protein might play a critical role in viral replication, and further, may represent an innovative opportunity to develop therapeutic interventions for alphavirus infection.

  14. Human monoclonal antibodies in single chain fragment variable format with potent neutralization activity against influenza virus H5N1.

    Science.gov (United States)

    Ascione, Alessandro; Capecchi, Barbara; Campitelli, Laura; Imperiale, Valentina; Flego, Michela; Zamboni, Silvia; Gellini, Mara; Alberini, Isabella; Pittiglio, Eliana; Donatelli, Isabella; Temperton, Nigel J; Cianfriglia, Maurizio

    2009-09-01

    Effective diagnostic and therapeutic strategies are needed to control and combat the highly pathogenic avian influenza virus (AIV) subtype H5N1. To this end, we developed human monoclonal antibodies (mAbs) in single chain fragment variable (scFv) format towards the H5N1 avian influenza virus to gain new insights for the development of immunotherapy against human cases of H5N1. Using a biopanning based approach a large array of scFvs against H5N1 virus were isolated from the human semi-synthetic ETH-2 phage antibody library. H5N1 ELISA-positive scFvs with unique variable heavy (VH) and light (VL) chain gene sequences showed different biochemical properties and neutralization activity across H5N1 viral strains. In particular, the scFv clones AV.D1 and AV.C4 exerted a significant inhibition of the H5N1 A/Vietnam/1194/2004 virus infection in a pseudotype-based neutralization assay. Interestingly, these two scFvs displayed a cross-clade neutralizing activity versus A/whooping swan/Mongolia/244/2005 and A/Indonesia/5/2005 strains. These studies provide proof of the concept that human mAbs in scFv format with well-defined H5N1 recognition patterns and in vitro neutralizing activity can be easily and rapidly isolated by biopanning selection of an entirely artificial antibody repertoire using inactivated H5N1 virus as a bait.

  15. Evaluation ofIn vitroAntiviral Activity ofDatura metelLinn. Against Rabies Virus.

    Science.gov (United States)

    Roy, Soumen; Mukherjee, Sandeepan; Pawar, Sandip; Chowdhary, Abhay

    2016-01-01

    The soxhlet and cold extracts of Datura metel Linn. were evaluated for in vitro antirabies activity. Soxhlet and cold extraction method were used to extract Datura (fruit and seed) extracts. In vitro cytotoxicity assay was performed by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay. Based on the CC50 range, the in vitro antirabies activity of the extracts was screened by rapid fluorescent focus inhibition test and molecular method. The Datura (fruit and seed) extracts were not cytotoxic below 5 mg/ml (CC50). Titer of 10 -4 rabies virus challenge virus standard (RV CVS) (1 50% tissue culture infective dose [1 TCID50]) was obtained by RFFT method and the challenge dose of 10 TCID50 was used for antirabies assay. Datura fruit and seed (soxhlet and cold) extracts showed 50% inhibition of RV CVS at 2.5 mg/ml and 1.25 mg/ml (inhibitory concentration 50% [IC50]), respectively. The tested extracts showed selectivity index (CC50/IC50) ranging from 2 to 4. The viral RNA was extracted and real-time reverse transcription-polymerase chain reaction was performed which also revealed a 2-fold reduction of viral load at 1.25 mg/ml of the Datura seed (soxhlet methanolic and cold aqueous) extracts. To the best of our knowledge, this is the first study of in vitro antiviral activity of D. metel Linn. against rabies virus. Datura seed extracts have a potential in vitro antirabies activity and, in future, can be further screened for in vivo activity against rabies virus in murine model. In the present study, Datura metel . Linn showed and in-vitro anti rabies activity in Vero cell line which was determined by RFFIT method and PCR method.

  16. Structure of Epstein-Barr Virus Glycoprotein 42 Suggests a Mechanism for Triggering Receptor-Activated Virus Entry

    Energy Technology Data Exchange (ETDEWEB)

    Kirschner, Austin N.; Sorem, Jessica; Longnecker, Richard; Jardetzky, Theodore S.; (NWU); (Stanford-MED)

    2009-05-26

    Epstein-Barr virus requires glycoproteins gH/gL, gB, and gp42 to fuse its lipid envelope with B cells. Gp42 is a type II membrane protein consisting of a flexible N-terminal region, which binds gH/gL, and a C-terminal lectin-like domain that binds to the B-cell entry receptor human leukocyte antigen (HLA) class II. Gp42 triggers membrane fusion after HLA binding, a process that requires simultaneous binding to gH/gL and a functional hydrophobic pocket in the lectin domain adjacent to the HLA binding site. Here we present the structure of gp42 in its unbound form. Comparisons to the previously determined structure of a gp42:HLA complex reveals additional N-terminal residues forming part of the gH/gL binding site and structural changes in the receptor binding domain. Although the core of the lectin domain remains similar, significant shifts in two loops and an {alpha} helix bordering the essential hydrophobic pocket suggest a structural mechanism for triggering fusion.

  17. US6 Gene Deletion in Herpes Simplex Virus Type 2 Enhances Dendritic Cell Function and T Cell Activation

    Science.gov (United States)

    Retamal-Díaz, Angello; Weiss, Kayla A.; Tognarelli, Eduardo I.; Freire, Mariela; Bueno, Susan M.; Herold, Betsy C.; Jacobs, William R.; González, Pablo A.

    2017-01-01

    Herpes simplex virus (HSV) type 1 (HSV-1) and type 2 (HSV-2) produce lifelong infections that are associated with frequent asymptomatic or clinically apparent reactivation. Importantly, HSV express multiple virulence factors that negatively modulate innate and adaptive immune components. Notably, HSV interfere with dendritic cell (DC) viability and function, likely hindering the capacity of the host to mount effective immunity against these viruses. Recently, an HSV-2 virus that was deleted in glycoprotein D was engineered (designated ΔgD-2). The virus is propagated on a complementing cell line that expresses HSV-1 gD, which permits a single round of viral replication. ΔgD-2 is safe, immunogenic, and provided complete protection against vaginal or skin challenges with HSV-1 and HSV-2 in murine models. Here, we sought to assess the interaction of ΔgD-2 with DCs and found that, in contrast to wild-type (WT) virus which induces DC apoptosis, ΔgD-2 promoted their migration and capacity to activate naïve CD8+ and CD4+ T cells in vitro and in vivo. Furthermore, DCs exposed to the WT and ΔgD-2 virus experienced different unfolded protein responses. Mice primed with DCs infected with ΔgD-2 in vitro displayed significantly reduced infection and pathology after genital challenge with virulent HSV-2 compared to non-primed mice, suggesting that DCs play a role in the immune response to the vaccine strain. PMID:29176979

  18. Mild to moderate influenza activity in Europe and the detection of novel A (H1N2) and B viruses during the winter of 2001-02.

    NARCIS (Netherlands)

    Paget, W.J.; Meerhoff, T.J.; Goddard, N.L.

    2002-01-01

    Influenza activity in Europe during the 2001-02 influenza season was mild to moderate. Compared to historical data, the intensity was low in six countries, medium in eleven and high in one country (Spain). The dominant virus circulating in Europe was influenza A(H3N2). Two novel influenza virus

  19. The proteolytic activation of (H3N2) influenza A virus hemagglutinin is facilitated by different type II transmembrane serine proteases

    NARCIS (Netherlands)

    N. Kühn (Nora); S. Bergmann (Silke); N. Kösterke (Nadine); R.L.O. Lambertz (Ruth L.O.); A. Keppner (Anna); J.M.A. van den Brand (Judith); S. Pöhlmann (Stefan); S. Weiß (Siegfried); E. Hummler (Edith); B. Hatesuer (Bastian); K. Schughart (Klaus)

    2016-01-01

    textabstractCleavage of influenza virus hemagglutinin (HA) by host cell proteases is necessary for viral activation and infectivity. In humans and mice, members of the type II transmembrane protease family (TTSP), e.g., TMPRSS2, TMPRSS4, and TMPRSS11d (HAT), have been shown to cleave influenza virus

  20. Pepino mosaic virus triple gene block protein 1 (TGBp1) interacts with and increases tomato catalase 1 activity to enhance virus accumulation.

    Science.gov (United States)

    Mathioudakis, Matthaios M; Veiga, Rita S L; Canto, Tomas; Medina, Vicente; Mossialos, Dimitris; Makris, Antonios M; Livieratos, Ioannis

    2013-08-01

    Various plant factors are co-opted by virus elements (RNA, proteins) and have been shown to act in pathways affecting virus accumulation and plant defence. Here, an interaction between Pepino mosaic virus (PepMV) triple gene block protein 1 (TGBp1; p26) and tomato catalase 1 (CAT1), a crucial enzyme in the decomposition of toxic hydrogen peroxide (H₂O₂), was identified using the yeast two-hybrid assay, and confirmed via an in vitro pull-down assay and bimolecular fluorescent complementation (BiFC) in planta. Each protein was independently localized within loci in the cytoplasm and nuclei, sites at which their interaction had been visualized by BiFC. Following PepMV inoculation, CAT mRNA and protein levels in leaves were unaltered at 0, 3 and 6 days (locally) and 8 days (systemically) post-inoculation; however, leaf extracts from the last two time points contained increased CAT activity and lower H₂O₂ evels. Overexpression of PepMV p26 in vitro and in planta conferred the same effect, suggesting an additional involvement of TGBp1 in potexvirus pathogenesis. The accumulation of PepMV genomic and subgenomic RNAs and the expression of viral coat protein in noninoculated (systemic) leaves were reduced significantly in CAT-silenced plants. It is postulated that, during PepMV infection, a p26-CAT1 interaction increases H₂O₂ cavenging, thus acting as a negative regulator of plant defence mechanisms to promote PepMV infections. © 2013 BSPP AND JOHN WILEY & SONS LTD.

  1. Activation of type I and III interferon signalling pathways occurs in lung epithelial cells infected with low pathogenic avian influenza viruses.

    Directory of Open Access Journals (Sweden)

    Richard Sutejo

    Full Text Available The host response to the low pathogenic avian influenza (LPAI H5N2, H5N3 and H9N2 viruses were examined in A549, MDCK, and CEF cells using a systems-based approach. The H5N2 and H5N3 viruses replicated efficiently in A549 and MDCK cells, while the H9N2 virus replicated least efficiently in these cell types. However, all LPAI viruses exhibited similar and higher replication efficiencies in CEF cells. A comparison of the host responses of these viruses and the H1N1/WSN virus and low passage pH1N1 clinical isolates was performed in A549 cells. The H9N2 and H5N2 virus subtypes exhibited a robust induction of Type I and Type III interferon (IFN expression, sustained STAT1 activation from between 3 and 6 hpi, which correlated with large increases in IFN-stimulated gene (ISG expression by 10 hpi. In contrast, cells infected with the pH1N1 or H1N1/WSN virus showed only small increases in Type III IFN signalling, low levels of ISG expression, and down-regulated expression of the IFN type I receptor. JNK activation and increased expression of the pro-apoptotic XAF1 protein was observed in A549 cells infected with all viruses except the H1N1/WSN virus, while MAPK p38 activation was only observed in cells infected with the pH1N1 and the H5 virus subtypes. No IFN expression and low ISG expression levels were generally observed in CEF cells infected with either AIV, while increased IFN and ISG expression was observed in response to the H1N1/WSN infection. These data suggest differences in the replication characteristics and antivirus signalling responses both among the different LPAI viruses, and between these viruses and the H1N1 viruses examined. These virus-specific differences in host cell signalling highlight the importance of examining the host response to avian influenza viruses that have not been extensively adapted to mammalian tissue culture.

  2. Epstein–Barr Virus Susceptibility in Activated PI3Kδ Syndrome (APDS Immunodeficiency

    Directory of Open Access Journals (Sweden)

    Jean-Marie Carpier

    2018-01-01

    Full Text Available Activated PI3Kδ Syndrome (APDS is an inherited immune disorder caused by heterozygous, gain-of-function mutations in the genes encoding the phosphoinositide 3-kinase delta (PI3Kδ subunits p110δ or p85δ. This recently described primary immunodeficiency disease (PID is characterized by recurrent sinopulmonary infections, lymphoproliferation, and susceptibility to herpesviruses, with Epstein–Barr virus (EBV infection being most notable. A broad range of PIDs having disparate, molecularly defined genetic etiology can cause susceptibility to EBV, lymphoproliferative disease, and lymphoma. Historically, PID patients with loss-of-function mutations causing defective cell-mediated cytotoxicity or antigen receptor signaling were found to be highly susceptible to pathological EBV infection. By contrast, the gain of function in PI3K signaling observed in APDS patients paradoxically renders these patients susceptible to EBV, though the underlying mechanisms are incompletely understood. At a cellular level, APDS patients exhibit deranged B lymphocyte development and defects in class switch recombination, which generally lead to defective immunoglobulin production. Moreover, APDS patients also demonstrate an abnormal skewing of T cells toward terminal effectors with short telomeres and senescence markers. Here, we review APDS with a particular focus on how the altered lymphocyte biology in these patients may confer EBV susceptibility.

  3. Clinical activity of lenalidomide in visceral human immunodeficiency virus-related Kaposi sarcoma.

    Science.gov (United States)

    Steff, Maud; Joly, Véronique; Di Lucca, Julie; Feldman, Judith; Burg, Samuel; Sarda-Mantel, Laure; Peytavin, Gilles; Marinho, Eduardo; Crickx, Béatrice; Raymond, Eric; Lariven, Sylvie; Maubec, Eve

    2013-11-01

    Curative treatment of aggressive Kaposi sarcoma (KS) with conventional chemotherapy in human immunodeficiency virus (HIV)-infected patients remains difficult. The administration of thalidomide, an immunomodulatory drug with antiangiogenic effects, is limited by its toxicity. This engenders interest in evaluating thalidomide analogues such as lenalidomide with better toxicity profiles. To our knowledge, we describe for the first time a patient with visceral KS successfully treated with lenalidomide. A man with advanced visceral HIV-related KS progressing after 11 months of highly active antiretroviral therapy (HAART) and 2 lines of conventional chemotherapy (pegylated liposomal doxorubicin and docetaxel) was treated with lenalidomide on a compassionate use basis. He showed a rapid partial response without any substantial adverse effect but experienced relapse after 5 months of treatment, in a context of virologic failure. Similar to our observation, good partial response without toxic effects has been reported in 3 patients with only skin involvement. Because immune reconstitution syndrome may occur in HIV-infected patients with KS undergoing HAART, KS improvement may be partly explained by immune recovery. An ongoing US phase 1/2 trial will better evaluate the efficacy and tolerance of lenalidomide in patients with HIV-related KS with and without visceral involvement.

  4. Application of speckle dynamics for studying metabolic activity of cell cultures with herpes virus

    Science.gov (United States)

    Vladimirov, A. P.; Bakharev, A. A.; Malygin, A. S.; Mikhaylova, J. A.; Borodin, E. M.; Poryvayeva, A. P.; Glinskikh, N. P.

    2014-05-01

    The report considers the results of the experiments in which digital values of light intensity I and the image area correlation index η values were recorded on a real-time basis for one or two days. Three cell cultures with viruses along with intact cultures were investigated. High correlation of dependence of η values on time t values was demonstrated for three cultures. The η=η(t) and I=I(t) dependences for cells with and without viruses differ considerably. It was shown that the presence of viruses could be determined as early as ten minutes after measurements were started.

  5. Partial antiviral activities detection of chicken Mx jointing with neuraminidase gene (NA against Newcastle disease virus.

    Directory of Open Access Journals (Sweden)

    Yani Zhang

    Full Text Available As an attempt to increase the resistance to Newcastle Disease Virus (NDV and so further reduction of its risk on the poultry industry. This work aimed to build the eukaryotic gene co-expression plasmid of neuraminidase (NA gene and myxo-virus resistance (Mx and detect the gene expression in transfected mouse fibroblasts (NIH-3T3 cells, it is most important to investigate the influence of the recombinant plasmid on the chicken embryonic fibroblasts (CEF cells. cDNA fragment of NA and mutant Mx gene were derived from pcDNA3.0-NA and pcDNA3.0-Mx plasmid via PCR, respectively, then NA and Mx cDNA fragment were inserted into the multiple cloning sites of pVITRO2 to generate the eukaryotic co-expression plasmid pVITRO2-Mx-NA. The recombinant plasmid was confirmed by restriction endonuclease treatment and sequencing, and it was transfected into the mouse fibroblasts (NIH-3T3 cells. The expression of genes in pVITRO2-Mx-NA were measured by RT-PCR and indirect immunofluorescence assay (IFA. The recombinant plasmid was transfected into CEF cells then RT-PCR and the micro-cell inhibition tests were used to test the antiviral activity for NDV. Our results showed that co-expression vector pVITRO2-Mx-NA was constructed successfully; the expression of Mx and NA could be detected in both NIH-3T3 and CEF cells. The recombinant proteins of Mx and NA protect CEF cells from NDV infection until after 72 h of incubation but the individually mutagenic Mx protein or NA protein protects CEF cells from NDV infection till 48 h post-infection, and co-transfection group decreased significantly NDV infection compared with single-gene transfection group (P<0. 05, indicating that Mx-NA jointing contributed to delaying the infection of NDV in single-cell level and the co-transfection of the jointed genes was more powerful than single one due to their synergistic effects.

  6. Trans-activation of the JC virus late promoter by the tat protein of type 1 human immunodeficiency virus in glial cells

    International Nuclear Information System (INIS)

    Tada, Hiroomi; Lashgari, M.; Amini, S.; Khalili, K.; Rappaport, J.; Wong-Staal, F.

    1990-01-01

    Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system caused by the JC virus (JCV), a human papovavirus. PML is a relatively rare disease seen predominantly in immunocompromised individuals and is a frequent complication observed in AIDS patients. The significantly higher incidence of PML in AIDS patients than in other immunosuppressive disorders has suggested that the presence of human immunodeficiency virus type 1 (HIV-1) in the brain may directly or indirectly contribute to the pathogenesis of this disease. In the present study the authors have examined the expression of the JCV genome in both glial and non-glial cells in the presence of HIV-1 regulatory proteins. They find that the HIV-1-encoded trans-regulatory protein tat increases the basal activity of the JCV late promoter, JCV L , in glial cells. They conclude that the presence of the HIV-1-encoded tat protein may positively affect the JCV lytic cycle in glial cells by stimulating JCV gene expression. The results suggest a mechanism for the relatively high incidence of PML in AIDS patients than in other immunosuppressive disorders. Furthermore, the findings indicate that the HIV-1 regulatory protein tat may stimulate other viral and perhaps cellular promoters, in addition to its own

  7. A distinct subtype of Epstein Barr virus positive T/NK-cell lymphoproliferative disorder: Adult patients with chronic active Epstein Barr virus infection-like features.

    Science.gov (United States)

    Kawamoto, Keisuke; Miyoshi, Hiroaki; Suzuki, Takaharu; Kozai, Yasuji; Kato, Koji; Miyahara, Masaharu; Yujiri, Toshiaki; Oishi, Naoki; Choi, Ilseung; Fujimaki, Katsumichi; Muta, Tsuyoshi; Kume, Masaaki; Moriguchi, Sayaka; Tamura, Shinobu; Kato, Takeharu; Tagawa, Hiroyuki; Makiyama, Junya; Kanisawa, Yuji; Sasaki, Yuya; Kurita, Daisuke; Yamada, Kyohei; Shimono, Joji; Sone, Hirohito; Takizawa, Jun; Seto, Masao; Kimura, Hiroshi; Ohshima, Koichi

    2017-12-14

    The characteristics of adult patients with chronic active Epstein-Barr virus infection (adult-onset CAEBV) are poorly recognized, hindering early diagnosis and an improved prognosis. Adult-onset CAEBV (n = 54) diagnosed between 2005 and 2015 were conducted. Adult-onset was defined as an estimated age of onset ≥15 years. To characterize the clinical features of adult-onset CAEBV, we compared them to those of pediatric-onset (estimated age of onset Epstein-Barr virus nuclear antigen antibody titer, and the presence of hemophagocytic syndrome were associated with a poor prognosis (P = 0.0087, P = 0.0236, and P = 0.0149, respectively). Allogeneic hematopoietic stem cell transplantation may improve survival (P = 0.0289). Compared to that for pediatric-onset CAEBV and ENKTL, adult-onset CAEBV had a poorer prognosis (P < 0.001 and P = 0.0484, respectively). CAEBV can develop in a wide age-range, with clinical differences between adult-onset and pediatric-onset CAEBV. Adult-onset CAEBV is a disease with a poor prognosis and further research is needed. Copyright © 2017, Ferrata Storti Foundation.

  8. Cross-Reactive and Cross-Neutralizing Activity of Human Mumps Antibodies Against a Novel Mumps Virus From Bats.

    Science.gov (United States)

    Beaty, Shannon M; Nachbagauer, Raffael; Hirsh, Ariana; Vigant, Frederic; Duehr, James; Azarm, Kristopher D; Stelfox, Alice J; Bowden, Thomas A; Duprex, W Paul; Krammer, Florian; Lee, Benhur

    2017-01-15

    To evaluate the antigenic relationship between bat mumps virus (BMV) and the JL5 vaccine strain of mumps virus (MuVJL5), we rescued a chimeric virus bearing the F and HN glycoproteins of BMV in the background of a recombinant JL5 genome (rMuVJL5). Cross-reactivity and cross-neutralization between this chimeric recombinant MuV bearing the F and HN glycoproteins of BMV (rMuVJL5-F/HNBMV) virus and rMuVJL5 were demonstrated using hyperimmune mouse serum samples and a curated panel of human serum. All mouse and human serum samples that were able to neutralize rMuVJL5 infection had cross-neutralizing activity against rMuVJL5-F/HNBMV. Our data suggest that persons who have neutralizing antibodies against MuV might be protected from infection by BMV. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  9. Suppressing active replication of a live attenuated simian immunodeficiency virus vaccine does not abrogate protection from challenge

    International Nuclear Information System (INIS)

    Gabriel, Benjamin; Fiebig, Uwe; Hohn, Oliver; Plesker, Roland; Coulibaly, Cheick; Cichutek, Klaus; Mühlebach, Michael D.; Bannert, Norbert; Kurth, Reinhard; Norley, Stephen

    2016-01-01

    Although safety concerns preclude the use of live attenuated HIV vaccines in humans, they provide a useful system for identifying the elusive correlates of protective immunity in the SIV/macaque animal model. However, a number of pieces of evidence suggest that protection may result from prior occupancy of susceptible target cells by the vaccine virus rather than the immune response. To address this, we developed a Nef-deletion variant of an RT-SHIV whose active replication could be shut off by treatment with RT-inhibitors. Groups of macaques were inoculated with the ∆Nef-RT-SHIV and immune responses allowed to develop before antiretroviral treatment and subsequent challenge with wild-type SIVmac239. Vaccinated animals either resisted infection fully or significantly controlled the subsequent viremia. However, there was no difference between animals undergoing replication of the vaccine virus and those without. This strongly suggests that competition for available target cells does not play a role in protection. - Highlights: • A Nef-deleted RT-SHIV was used as a live attenuated vaccine in macaques. • Vaccine virus replication was shut down to investigate its role in protection. • Ongoing vaccine virus replication did not appear to be necessary for protection. • An analysis of T- and B-cell responses failed to identify a correlate of protection.

  10. Early detection of tick-borne encephalitis virus spatial distribution and activity in the province of Trento, northern Italy

    Directory of Open Access Journals (Sweden)

    Annapaola Rizzoli

    2007-05-01

    Full Text Available New human cases of tick-borne encephalitis (TBE have recently been recorded outside the recognised foci of this disease, i.e. in the province of Trento in northern Italy. In order to predict the highest risk areas for increased TBE virus activity, we have combined cross-sectional serological data, obtained from 459 domestic goats, with analysis of the autumnal cooling rate based on Moderate Resolution Imaging Spectroradiometer (MODIS land surface temperature (LST data. A significant relationship between finding antibodies against the virus in serum (seroprevalence in goats and the autumnal cooling rate was detected, indicating that the transmission intensity of the virus does not only vary spatially, but also in relation to climatic factors. Virus seroprevalence in goats was correlated with the occurrence of TBE in humans and also with the average number of forestry workers’ tick bites, demonstrating that serological screening of domestic animals, combined with an analysis of the autumnal cooling rate, can be used as early-warning predictors of TBE risk in humans.

  11. MEK/ERK activation plays a decisive role in yellow fever virus replication: implication as an antiviral therapeutic target.

    Science.gov (United States)

    Albarnaz, Jonas D; De Oliveira, Leonardo C; Torres, Alice A; Palhares, Rafael M; Casteluber, Marisa C; Rodrigues, Claudiney M; Cardozo, Pablo L; De Souza, Aryádina M R; Pacca, Carolina C; Ferreira, Paulo C P; Kroon, Erna G; Nogueira, Maurício L; Bonjardim, Cláudio A

    2014-11-01

    Exploiting the inhibition of host signaling pathways aiming for discovery of potential antiflaviviral compounds is clearly a beneficial strategy for the control of life-threatening diseases caused by flaviviruses. Here we describe the antiviral activity of the MEK1/2 inhibitor U0126 against Yellow fever virus 17D vaccine strain (YFV-17D). Infection of VERO cells with YFV-17D stimulates ERK1/2 phosphorylation early during infection. Pharmacological inhibition of MEK1/2 through U0126 treatment of VERO cells blockades not only the YFV-stimulated ERK1/2 phosphorylation, but also inhibits YFV replication by ∼99%. U0126 was also effective against dengue virus (DENV-2 and -3) and Saint-Louis encephalitis virus (SLEV). Levels of NS4AB, as detected by immunofluorescence, are diminished upon treatment with the inhibitor, as well as the characteristic endoplasmic reticulum membrane invagination stimulated during the infection. Though not protective, treatment of YFV-infected, adult BALB/c mice with U0126 resulted in significant reduction of virus titers in brains. Collectively, our data suggest the potential targeting of the MEK1/2 kinase as a therapeutic tool against diseases caused by flaviviruses such as yellow fever, adverse events associated with yellow fever vaccination and dengue. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Detection of Active Epstein-Barr Virus Infection in Duodenal Mucosa of Patients With Refractory Celiac Disease.

    Science.gov (United States)

    Perfetti, Vittorio; Baldanti, Fausto; Lenti, Marco Vincenzo; Vanoli, Alessandro; Biagi, Federico; Gatti, Marta; Riboni, Roberta; Dallera, Elena; Paulli, Marco; Pedrazzoli, Paolo; Corazza, Gino Roberto

    2016-08-01

    Refractory celiac disease is characterized by mucosal damage in patients with celiac disease despite a gluten-free diet. Little is known about the mechanisms that cause persistent intestinal inflammation in these patients. We performed a case-control study of 17 consecutive patients diagnosed with refractory celiac disease from 2001 through 2014 (median age, 51 y; 10 women) and 24 patients with uncomplicated celiac disease (controls) to determine whether refractory disease is associated with infection by lymphotropic oncogenic viruses. We performed real-time PCR analyses of duodenal biopsy samples from all patients to detect Epstein-Barr virus (EBV), human herpesvirus-8, and human T-cell lymphotropic virus-I, -II, or -III. We used in situ hybridization and immunohistochemical analyses to identify infected cells and viral proteins. We did not detect human herpesvirus-8 or human T-cell lymphotropic viruses in any of the biopsy specimens. However, 12 of 17 (70.5%) biopsy specimens from patients with refractory celiac disease were positive for EBV, compared with 4 of 24 (16.6%) biopsy specimens from controls (P < .001). EBV was detected in inflammatory cells and enterocytes. An analysis of latency- and replication-associated proteins confirmed active infection. Further studies are needed to determine whether EBV infection contributes to the pathogenesis of refractory celiac disease and enteropathy-associated T-cell lymphoma. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

  13. Lersivirine, a Nonnucleoside Reverse Transcriptase Inhibitor with Activity against Drug-Resistant Human Immunodeficiency Virus Type 1▿ ‡

    Science.gov (United States)

    Corbau, Romuald; Mori, Julie; Phillips, Chris; Fishburn, Lesley; Martin, Alex; Mowbray, Charles; Panton, Wendy; Smith-Burchnell, Caroline; Thornberry, Adele; Ringrose, Heather; Knöchel, Thorsten; Irving, Steve; Westby, Mike; Wood, Anthony; Perros, Manos

    2010-01-01

    The nonnucleoside reverse transcriptase inhibitors (NNRTIs) are key components of highly active antiretroviral therapy (HAART) for the treatment of human immunodeficiency virus type 1 (HIV-1). A major problem with the first approved NNRTIs was the emergence of mutations in the HIV-1 reverse transcriptase (RT), in particular K103N and Y181C, which led to resistance to the entire class. We adopted an iterative strategy to synthesize and test small molecule inhibitors from a chemical series of pyrazoles against wild-type (wt) RT and the most prevalent NNRTI-resistant mutants. The emerging candidate, lersivirine (UK-453,061), binds the RT enzyme in a novel way (resulting in a unique resistance profile), inhibits over 60% of viruses bearing key RT mutations, with 50% effective concentrations (EC50s) within 10-fold of those for wt viruses, and has excellent selectivity against a range of human targets. Altogether lersivirine is a highly potent and selective NNRTI, with excellent efficacy against NNRTI-resistant viruses. PMID:20660667

  14. Lersivirine, a nonnucleoside reverse transcriptase inhibitor with activity against drug-resistant human immunodeficiency virus type 1.

    Science.gov (United States)

    Corbau, Romuald; Mori, Julie; Phillips, Chris; Fishburn, Lesley; Martin, Alex; Mowbray, Charles; Panton, Wendy; Smith-Burchnell, Caroline; Thornberry, Adele; Ringrose, Heather; Knöchel, Thorsten; Irving, Steve; Westby, Mike; Wood, Anthony; Perros, Manos

    2010-10-01

    The nonnucleoside reverse transcriptase inhibitors (NNRTIs) are key components of highly active antiretroviral therapy (HAART) for the treatment of human immunodeficiency virus type 1 (HIV-1). A major problem with the first approved NNRTIs was the emergence of mutations in the HIV-1 reverse transcriptase (RT), in particular K103N and Y181C, which led to resistance to the entire class. We adopted an iterative strategy to synthesize and test small molecule inhibitors from a chemical series of pyrazoles against wild-type (wt) RT and the most prevalent NNRTI-resistant mutants. The emerging candidate, lersivirine (UK-453,061), binds the RT enzyme in a novel way (resulting in a unique resistance profile), inhibits over 60% of viruses bearing key RT mutations, with 50% effective concentrations (EC(50)s) within 10-fold of those for wt viruses, and has excellent selectivity against a range of human targets. Altogether lersivirine is a highly potent and selective NNRTI, with excellent efficacy against NNRTI-resistant viruses.

  15. Suppressing active replication of a live attenuated simian immunodeficiency virus vaccine does not abrogate protection from challenge

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, Benjamin; Fiebig, Uwe; Hohn, Oliver [Robert Koch-Institut, Berlin (Germany); Plesker, Roland; Coulibaly, Cheick; Cichutek, Klaus; Mühlebach, Michael D. [Paul-Ehrlich-Institut, Langen (Germany); Bannert, Norbert; Kurth, Reinhard [Robert Koch-Institut, Berlin (Germany); Norley, Stephen, E-mail: NorleyS@rki.de [Robert Koch-Institut, Berlin (Germany)

    2016-02-15

    Although safety concerns preclude the use of live attenuated HIV vaccines in humans, they provide a useful system for identifying the elusive correlates of protective immunity in the SIV/macaque animal model. However, a number of pieces of evidence suggest that protection may result from prior occupancy of susceptible target cells by the vaccine virus rather than the immune response. To address this, we developed a Nef-deletion variant of an RT-SHIV whose active replication could be shut off by treatment with RT-inhibitors. Groups of macaques were inoculated with the ∆Nef-RT-SHIV and immune responses allowed to develop before antiretroviral treatment and subsequent challenge with wild-type SIVmac239. Vaccinated animals either resisted infection fully or significantly controlled the subsequent viremia. However, there was no difference between animals undergoing replication of the vaccine virus and those without. This strongly suggests that competition for available target cells does not play a role in protection. - Highlights: • A Nef-deleted RT-SHIV was used as a live attenuated vaccine in macaques. • Vaccine virus replication was shut down to investigate its role in protection. • Ongoing vaccine virus replication did not appear to be necessary for protection. • An analysis of T- and B-cell responses failed to identify a correlate of protection.

  16. CNS activity of Pokeweed Anti-viral Protein (PAP in mice infected with Lymphocytic Choriomeningitis Virus (LCMV

    Directory of Open Access Journals (Sweden)

    Tibbles Heather E

    2005-02-01

    Full Text Available Abstract Background Others and we have previously described the potent in vivo and in vitro activity of the broad-spectrum antiviral agent PAP (Pokeweed antiviral protein against a wide range of viruses. The purpose of the present study was to further elucidate the anti-viral spectrum of PAP by examining its effects on the survival of mice challenged with lymphocytic choriomeningitis virus (LCMV. Methods We examined the therapeutic effect of PAP in CBA mice inoculated with intracerebral injections of the WE54 strain of LCMV at a 1000 PFU dose level that is lethal to 100% of mice within 7–9 days. Mice were treated either with vehicle or PAP administered intraperitoneally 24 hours prior to, 1 hour prior to and 24 hours, 48 hours 72 hours and 96 hours after virus inoculation. Results PAP exhibits significant in vivo anti- LCMV activity in mice challenged intracerebrally with an otherwise invariably fatal dose of LCMV. At non-toxic dose levels, PAP significantly prolonged survival in the absence of the majority of disease-associated symptoms. The median survival time of PAP-treated mice was >21 days as opposed to 7 days median survival for the control (p = 0.0069. Conclusion Our results presented herein provide unprecedented experimental evidence that PAP exhibits antiviral activity in the CNS of LCMV-infected mice.

  17. Activated MEK Suppresses Activation of PKR and Enables Efficient Replication and In Vivo Oncolysis by Δγ134.5 Mutants of Herpes Simplex Virus 1

    Science.gov (United States)

    Smith, Kerrington D.; Mezhir, James J.; Bickenbach, Kai; Veerapong, Jula; Charron, Jean; Posner, Mitchell C.; Roizman, Bernard; Weichselbaum, Ralph R.

    2006-01-01

    Herpes simplex virus mutants lacking the γ134.5 gene are not destructive to normal tissues but are potent cytolytic agents in human tumor cells in which the activation of double-stranded RNA-dependent protein kinase (PKR) is suppressed. Thus, replication of a Δγ134.5 mutant (R3616) in 12 genetically defined cancer cell lines correlates with suppression of PKR but not with the genotype of RAS. Extensive analyses of two cell lines transduced with either dominant negative MEK (dnMEK) or constitutively active MEK (caMEK) indicated that in R3616 mutant-infected cells dnMEK enabled PKR activation and decreased virus yields, whereas caMEK suppressed PKR and enabled better viral replication and cell destruction in transduced cells in vitro or in mouse xenografts. The results indicate that activated MEK mediates the suppression of PKR and that the status of MEK predicts the ability of Δγ134.5 mutant viruses to replicate in and destroy tumor cells. PMID:16414988

  18. Distribution and characterization of environmental promoter substances as assayed by synergistic Epstein-Barr virus-activating system.

    Science.gov (United States)

    Ito, Y; Tokuda, H; Ohigashi, H; Koshimizu, K

    1983-01-01

    The application of a new screening procedure which utilizes the synergistic effect of short-chain fatty acids and tumor-promoting diterpene esters enabled rapid and easy detection of environmental substances with Epstein-Barr virus (EBV)-activating/tumor-promoting potency. Over 500 samples were tested and more than 30 substances with such activities were identified. Most, if not all, were plant diterpene esters derived from Euphorbiaceae and Thymelaeaceae families and a few were indole alkaloids of microbial origin. We attempted to link these laboratory findings with those of epidemiological field studies on three virus-associated diseases, Burkitt's lymphoma, nasopharyngeal carcinoma, and adult T-cell leukemia/lymphoma, which are known to have a peculiar geographical distribution. Our hypothesis was that EBV-activating/tumor-promoting substances might be present in the abundant areas where such diseases are endemic. We noticed that many active diterpene ester-containing plants are widely used as herbal medicaments in Africa and China and determined many plant species that had such activities. One example is Aleurites fordii, a plant commonly grown in Southern China for industrial purposes which yielded a potent promoter substance (12-O-hexadecanoyl-16-hydroxyphorbol-13-acetate, HHPA). The active diterpene esters were purified and their possible mechanism was studied from the view of receptor-binding, protein kinase C activation and transmembrane signaling.

  19. Autophagy is involved in anti-viral activity of pentagalloylglucose (PGG) against Herpes simplex virus type 1 infection in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Ying, E-mail: peiying-19802@163.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Chen, Zhen-Ping, E-mail: 530670663@qq.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Ju, Huai-Qiang, E-mail: 344464448@qq.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Komatsu, Masaaki, E-mail: komatsu-ms@igakuken.or.jp [Laboratory of Frontier Science, Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo 113-8613 (Japan); Ji, Yu-hua, E-mail: tjyh@jnu.edu.cn [Institute of Tissue Transplantation and Immunology, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China); Liu, Ge, E-mail: lggege_15@hotmail.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Guo, Chao-wan, E-mail: chaovan_kwok@hotmail.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Zhang, Ying-Jun, E-mail: zhangyj@mail.kib.ac.cn [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China); Yang, Chong-Ren, E-mail: cryang@mail.kib.ac.cn [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China); Wang, Yi-Fei, E-mail: twang-yf@163.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Kitazato, Kaio, E-mail: kkholi@msn.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan)

    2011-02-11

    Research highlights: {yields} We showed PGG has anti-viral activity against Herpes simplex virus type 1 (HSV-1) and can induce autophgy. {yields} Autophagy may be a novel and important mechanism mediating PGG anti-viral activities. {yields} Inhibition of mTOR pathway is an important mechanism of induction of autophagy by PGG. -- Abstract: Pentagalloylglucose (PGG) is a natural polyphenolic compound with broad-spectrum anti-viral activity, however, the mechanisms underlying anti-viral activity remain undefined. In this study, we investigated the effects of PGG on anti-viral activity against Herpes simplex virus type 1 (HSV-1) associated with autophagy. We found that the PGG anti-HSV-1 activity was impaired significantly in MEF-atg7{sup -/-} cells (autophagy-defective cells) derived from an atg7{sup -/-} knockout mouse. Transmission electron microscopy revealed that PGG-induced autophagosomes engulfed HSV-1 virions. The mTOR signaling pathway, an essential pathway for the regulation of autophagy, was found to be suppressed following PGG treatment. Data presented in this report demonstrated for the first time that autophagy induced following PGG treatment contributed to its anti-HSV activity in vitro.

  20. Chemical Synthesis and In Vitro Evaluation of a Phage Display-Derived Peptide Active against Infectious Salmon Anemia Virus.

    Science.gov (United States)

    Ojeda, Nicolás; Cárdenas, Constanza; Guzmán, Fanny; Marshall, Sergio H

    2016-04-01

    Infectious salmon anemia virus (ISAV) is the etiological agent of the disease by the same name and causes major losses in the salmon industry worldwide. Epizootic ISAV outbreaks have occurred in Norway and, to a lesser degree, in Canada. In 2007, an ISAV outbreak in Chile destroyed most of the seasonal production and endangered the entire Chilean salmon industry. None of the existing prophylactic approaches have demonstrated efficacy in providing absolute protection from or even a palliative effect on ISAV proliferation. Sanitary control measures for ISAV, based on molecular epidemiology data, have proven insufficient, mainly due to high salmon culture densities and a constant presence of a nonpathogenic strain of the virus. This report describes an alternative treatment approach based on interfering peptides selected from a phage display library. The screening of a phage display heptapeptide library resulted in the selection of a novel peptide with significant in vitro antiviral activity against ISAV. This peptide specifically interacted with the viral hemagglutinin-esterase protein, thereby impairing virus binding, with plaque reduction assays showing a significant reduction in viral yields. The identified peptide acts at micromolar concentrations against at least two different pathogenic strains of the virus, without detectable cytotoxic effects on the tested fish cells. Therefore, antiviral peptides represent a novel alternative for controlling ISAV and, potentially, other fish pathogens. Identifying novel methods for the efficient control of infectious diseases is imperative for the future of global aquaculture. The present study used a phage display heptapeptide library to identify a peptide with interfering activity against a key protein of the infectious salmon anemia virus (ISAV). A piscine orthomyxovirus, ISAV is a continuous threat to the commercial sustainability of cultured salmon production worldwide. The complex epidemiological strategy of this

  1. Host cell entry of respiratory syncytial virus involves macropinocytosis followed by proteolytic activation of the F protein.

    Directory of Open Access Journals (Sweden)

    Magdalena Anna Krzyzaniak

    Full Text Available Respiratory Syncytial Virus (RSV is a highly pathogenic member of the Paramyxoviridae that causes severe respiratory tract infections. Reports in the literature have indicated that to infect cells the incoming viruses either fuse their envelope directly with the plasma membrane or exploit clathrin-mediated endocytosis. To study the entry process in human tissue culture cells (HeLa, A549, we used fluorescence microscopy and developed quantitative, FACS-based assays to follow virus binding to cells, endocytosis, intracellular trafficking, membrane fusion, and infection. A variety of perturbants were employed to characterize the cellular processes involved. We found that immediately after binding to cells RSV activated a signaling cascade involving the EGF receptor, Cdc42, PAK1, and downstream effectors. This led to a series of dramatic actin rearrangements; the cells rounded up, plasma membrane blebs were formed, and there was a significant increase in fluid uptake. If these effects were inhibited using compounds targeting Na⁺/H⁺ exchangers, myosin II, PAK1, and other factors, no infection was observed. The RSV was rapidly and efficiently internalized by an actin-dependent process that had all hallmarks of macropinocytosis. Rather than fusing with the plasma membrane, the viruses thus entered Rab5-positive, fluid-filled macropinosomes, and fused with the membranes of these on the average 50 min after internalization. Rab5 was required for infection. To find an explanation for the endocytosis requirement, which is unusual among paramyxoviruses, we analyzed the fusion protein, F, and could show that, although already cleaved by a furin family protease once, it underwent a second, critical proteolytic cleavage after internalization. This cleavage by a furin-like protease removed a small peptide from the F1 subunits, and made the virus infectious.

  2. West Nile virus activity in Latin America and the Caribbean La actividad del virus del Nilo occidental en América Latina y el Caribe

    Directory of Open Access Journals (Sweden)

    Nicholas Komar

    2006-02-01

    Full Text Available OBJECTIVES: West Nile virus (Flavivirus: Flaviviridae; WNV has spread rapidly throughout the Caribbean Basin since its initial detection there in 2001. This report summarizes our current knowledge of WNV transmission in tropical America. METHODS: We reviewed the published literature and consulted with key public health officials to obtain unpublished data. RESULTS: West Nile virus infections first appeared in human residents of the Cayman Islands and the Florida Keys in 2001, and in apparently healthy Jamaican birds sampled early in 2002. Serologic evidence of WNV infection in 2002 was detected in horses, chickens and resident free-ranging birds in Guadeloupe, the Dominican Republic, and eastern Mexico. In 2003, WNV spread in Mexico and northern Central America, and serologic evidence was detected in the Bahamas, Puerto Rico and Cuba. In 2004, the first serologic evidence of WNV activity in South American ecosystems surfaced in September-October in Colombia and Trinidad, where domestic animals circulated WNV-neutralizing antibodies. CONCLUSIONS: The sparse reports of equine, human and avian disease in Latin America and the Caribbean is puzzling. Isolates are needed to evaluate viral attenuation or other possible explanations for reduced disease burden in tropical ecosystems.OBJETIVOS: El virus del Nilo occidental (VNO, familia Flaviviridae, género Flavivirus se ha propagado rápidamente por toda la cuenca del Caribe desde que se detectó por primera vez en 2001. En este informe se resumen nuestros conocimientos actuales acerca de la transmisión del VNO en zonas tropicales del continente americano. MÉTODOS: Revisamos todo lo que se ha publicado sobre el tema y consultamos a autoridades de salud clave para obtener datos inéditos. RESULTADOS: Las infecciones por el virus del Nilo occidental aparecieron por primera vez en seres humanos residentes de las Islas Caimán y de los Cayos de la Florida en 2001, y en pájaros de aspecto sano de los

  3. Aminotransferase elevation in HIV/hepatitis B virus co-infected patients treated with two active hepatitis B virus drugs.

    Science.gov (United States)

    Jain, Mamta K; Parekh, Nimisha K; Hester, Jill; Lee, William M

    2006-12-01

    Discerning drug hepatotoxicity from viral hepatitis flares remains an ongoing problem unique to patients coinfected with HIV and hepatitis B (HBV). We present three such coinfected patients who have been on two anti-HBV agents, lamivudine and tenofovir disoproxil fumarate simultaneously, as part of highly active antiretroviral therapy (HAART). All three developed significant aminotransferase elevations 6-12 weeks after initiation of HAART despite being on two active HBV drugs. Two of the three patients were initially thought to have drug-related hepatotoxicity from HIV medications. It seems more likely that all three patients demonstrated hepatitis B reactivation of differing severity as the result of varying degrees of immune recovery. Distinguishing clearly between drug-related hepatotoxicity and hepatitis reactivation may be difficult but is important as their clinical management differs.

  4. Sustained protein kinase D activation mediates respiratory syncytial virus-induced airway barrier disruption.

    Science.gov (United States)

    Rezaee, Fariba; DeSando, Samantha A; Ivanov, Andrei I; Chapman, Timothy J; Knowlden, Sara A; Beck, Lisa A; Georas, Steve N

    2013-10-01

    Understanding the regulation of airway epithelial barrier function is a new frontier in asthma and respiratory viral infections. Despite recent progress, little is known about how respiratory syncytial virus (RSV) acts at mucosal sites, and very little is known about its ability to influence airway epithelial barrier function. Here, we studied the effect of RSV infection on the airway epithelial barrier using model epithelia. 16HBE14o- bronchial epithelial cells were grown on Transwell inserts and infected with RSV strain A2. We analyzed (i) epithelial apical junction complex (AJC) function, measuring transepithelial electrical resistance (TEER) and permeability to fluorescein isothiocyanate (FITC)-conjugated dextran, and (ii) AJC structure using immunofluorescent staining. Cells were pretreated or not with protein kinase D (PKD) inhibitors. UV-irradiated RSV served as a negative control. RSV infection led to a significant reduction in TEER and increase in permeability. Additionally it caused disruption of the AJC and remodeling of the apical actin cytoskeleton. Pretreatment with two structurally unrelated PKD inhibitors markedly attenuated RSV-induced effects. RSV induced phosphorylation of the actin binding protein cortactin in a PKD-dependent manner. UV-inactivated RSV had no effect on AJC function or structure. Our results suggest that RSV-induced airway epithelial barrier disruption involves PKD-dependent actin cytoskeletal remodeling, possibly dependent on cortactin activation. Defining the mechanisms by which RSV disrupts epithelial structure and function should enhance our understanding of the association between respiratory viral infections, airway inflammation, and allergen sensitization. Impaired barrier function may open a potential new therapeutic target for RSV-mediated lung diseases.

  5. The 42-kDa coat protein of Andean potato mottle virus acts as a transcriptional activator in yeast

    Directory of Open Access Journals (Sweden)

    Vidal M.S.

    2002-01-01

    Full Text Available Interactions of viral proteins play an important role in the virus life cycle, especially in capsid assembly. Andean potato mottle comovirus (APMoV is a plant RNA virus with a virion formed by two coat proteins (CP42 and CP22. Both APMoV coat protein open reading frames were cloned into pGBT9 and pGAD10, two-hybrid system vectors. HF7c yeast cells transformed with the p9CP42 construct grew on yeast dropout selection media lacking tryptophan and histidine. Clones also exhibited ß-galactosidase activity in both qualitative and quantitative assays. These results suggest that CP42 protein contains an amino acid motif able to activate transcription of His3 and lacZ reporter genes in Saccharomyces cerevisiae. Several deletions of the CP42 gene were cloned into the pGBT9 vector to locate the region involved in this activation. CP42 constructions lacking 12 residues from the C-terminal region and another one with 267 residues deleted from the N-terminus are still able to activate transcription of reporter genes. However, transcription activation was not observed with construction p9CP42deltaC57, which does not contain the last 57 amino acid residues. These results demonstrate that a transcription activation domain is present at the C-terminus of CP42 between residues 267 and 374.

  6. Antiviral activity of benzotriazole derivatives. 5-[4-(Benzotriazol-2-yl)phenoxy]-2,2-dimethylpentanoic acids potently and selectively inhibit Coxsackie Virus B5.

    Science.gov (United States)

    Loddo, Roberta; Novelli, Federica; Sparatore, Anna; Tasso, Bruno; Tonelli, Michele; Boido, Vito; Sparatore, Fabio; Collu, Gabriella; Delogu, Ilenia; Giliberti, Gabriele; La Colla, Paolo

    2015-11-01

    A library of 64 benzotriazole derivatives (17 of which were [4-(benzotriazol-2-yl)phenoxy]alkanoic acids) were screened for antiviral activity against a panel of twelve DNA and RNA viruses. Twenty-six compounds (12 of which were [4-(benzotriazol-2-yl)phenoxy]alkanoic acids) displayed activity against one or more viruses. CVB-5, RSV, BVDV, Sb-1 and YFV were, in decreasing order, the more frequently and effectively affected viruses; DENV-2, WNV, HIV-1 and Reo-1 were only occasionally and modestly affected, while the remaining viruses were not affected by any of the tested compounds. Worth of note were compounds 33 and 35; the former for the activity against Sb-1 (EC50=7 μM) and the latter for the large spectrum of activity including six viruses with a mean EC50=12 μM. Even more interesting were the alkanoic acids 45-48 and 50-57 for their activity against RSV and/or CVB-5. In particular, compound 56 displayed a potent and selective activity against CVB-5 with EC50=0.15 μM and SI=100, thus representing a valuable hit compound for the development of antiviral agents for the treatment of human pathologies related to this virus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. High-Mannose Specific Lectin and Its Recombinants from a Carrageenophyta Kappaphycus alvarezii Represent a Potent Anti-HIV Activity Through High-Affinity Binding to the Viral Envelope Glycoprotein gp120.

    Science.gov (United States)

    Hirayama, Makoto; Shibata, Hiromi; Imamura, Koji; Sakaguchi, Takemasa; Hori, Kanji

    2016-02-01

    We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and complementary DNA (cDNA) cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per liter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48 - 1.61 × 10(9) M(-1)). Native KAAs and the recombinants inhibited the HIV-1 entry at IC50s of low nanomolar levels (7.3-12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).

  8. Adenovirus E4ORF1-induced MYC activation promotes host cell anabolic glucose metabolism and virus replication.

    Science.gov (United States)

    Thai, Minh; Graham, Nicholas A; Braas, Daniel; Nehil, Michael; Komisopoulou, Evangelia; Kurdistani, Siavash K; McCormick, Frank; Graeber, Thomas G; Christofk, Heather R

    2014-04-01

    Virus infections trigger metabolic changes in host cells that support the bioenergetic and biosynthetic demands of viral replication. Although recent studies have characterized virus-induced changes in host cell metabolism (Munger et al., 2008; Terry et al., 2012), the molecular mechanisms by which viruses reprogram cellular metabolism have remained elusive. Here, we show that the gene product of adenovirus E4ORF1 is necessary for adenovirus-induced upregulation of host cell glucose metabolism and sufficient to promote enhanced glycolysis in cultured epithelial cells by activation of MYC. E4ORF1 localizes to the nucleus, binds to MYC, and enhances MYC binding to glycolytic target genes, resulting in elevated expression of specific glycolytic enzymes. E4ORF1 activation of MYC promotes increased nucleotide biosynthesis from glucose intermediates and enables optimal adenovirus replication in primary lung epithelial cells. Our findings show how a viral protein exploits host cell machinery to reprogram cellular metabolism and promote optimal progeny virion generation. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Inhibition of plasmin, urokinase, tissue plasminogen activator, and C1S by a myxoma virus serine proteinase inhibitor.

    Science.gov (United States)

    Lomas, D A; Evans, D L; Upton, C; McFadden, G; Carrell, R W

    1993-01-05

    The myxoma and malignant rabbit fibroma poxviruses are lethal tumorigenic viruses of rabbits whose virulence is modulated by the production of a virus-encoded secreted serine proteinase inhibitor, SERP-1. This viral protein was detected in medium harvested from myxoma and malignant rabbit fibroma virus-infected cells, and its inhibitory profile has been characterized by gel and kinetic analysis. SERP-1 forms complexes with and inhibits the human fibrinolytic enzymes plasmin, urokinase, and two-chain tissue-type plasminogen activator (association rate constants 3.4 x 10(4), 4.3 x 10(4), and 3.6 x 10(4) M-1 s-1 respectively). It is also able to inhibit C1S, the first enzyme in the complement cascade with an association rate constant which was unaffected by the addition of heparin (1.3 x 10(3) M-1 s-1). SERP-1 acts as a substrate for and is cleaved by thrombin, porcine trypsin, human neutrophil elastase, porcine pancreatic elastase, thermolysin, subtilisin, bovine alpha-chymotrypsin, and factor Xa. Incubation with kallikrein and cathepsin G had no effect. The structure of SERP-1 has been modeled on other members of the serpin family which revealed the characteristic serpin architecture apart from the absence of the D-helix. Structural analysis and kinetic assays demonstrate that the absence of this region does not prevent inhibitory activity and furthermore allow the identification of cysteine residues involved in internal and intermolecular disulfide bonding.

  10. Concanavalin A-mediated in vitro activation of a secondary cytotoxic T-cell response in virus-primed splenocytes

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Jensen, B L

    1980-01-01

    In a recent report it was shown that what appeared to be secondary cytotoxic T cells could be obtained from lymphocytic choriomeningitis virus (LCMV)-primed splenocytes after stimulation in vitro with the non-specific T cell mitogen concanavalin A (Con A). The present experiments attempt to chara......In a recent report it was shown that what appeared to be secondary cytotoxic T cells could be obtained from lymphocytic choriomeningitis virus (LCMV)-primed splenocytes after stimulation in vitro with the non-specific T cell mitogen concanavalin A (Con A). The present experiments attempt...... to characterize further these effector cells and, in particular, to establish whether the Con A-activated cytotoxic effectors are qualitatively different from the secondary cytotoxic T cells induced by restimulation with the homologous antigen. It was found that: (1) in vitro activation with Con A could......, since no evidence was found to indicate a role for other cell types or soluble (cytotoxic or arming) factors; (4) cytotoxicity was specific with regard to both virus and 'self'. By comparison with previous data on LCMV-induced cytotoxic T cells, it is concluded that Con A induces the generation...

  11. Herpes Simplex Virus 1 DNA Polymerase RNase H Activity Acts in a 3'-to-5' Direction and Is Dependent on the 3'-to-5' Exonuclease Active Site.

    Science.gov (United States)

    Lawler, Jessica L; Mukherjee, Purba; Coen, Donald M

    2018-03-01

    The catalytic subunit (Pol) of herpes simplex virus 1 (HSV-1) DNA polymerase has been extensively studied both as a model for other family B DNA polymerases and for its differences from these enzymes as an antiviral target. Among the activities of HSV-1 Pol is an intrinsic RNase H activity that cleaves RNA from RNA-DNA hybrids. There has long been a controversy regarding whether this activity is due to the 3'-to-5' exonuclease of Pol or whether it is a separate activity, possibly acting on 5' RNA termini. To investigate this issue, we compared wild-type HSV-1 Pol and a 3'-to-5' exonuclease-deficient mutant, D368A Pol, for DNA polymerase activity, 3'-to-5' exonuclease activity, and RNase H activity in vitro Additionally, we assessed the RNase H activity using differentially end-labeled templates with 5' or 3' RNA termini. The mutant enzyme was at most modestly impaired for DNA polymerase activity but was drastically impaired for 3'-to-5' exonuclease activity, with no activity detected even at high enzyme-to-DNA substrate ratios. Importantly, the mutant showed no detectable ability to excise RNA with either a 3' or 5' terminus, while the wild-type HSV-1 Pol was able to cleave RNA from the annealed RNA-DNA hairpin template, but only detectably with a 3' RNA terminus in a 3'-to-5' direction and at a rate lower than that of the exonuclease activity. These results suggest that HSV-1 Pol does not have an RNase H separable from its 3'-to-5' exonuclease activity and that this activity prefers DNA degradation over degradation of RNA from RNA-DNA hybrids. IMPORTANCE Herpes simplex virus 1 (HSV-1) is a member of the Herpesviridae family of DNA viruses, several of which cause morbidity and mortality in humans. Although the HSV-1 DNA polymerase has been studied for decades and is a crucial target for antivirals against HSV-1 infection, several of its functions remain to be elucidated. A hypothesis suggesting the existence of a 5'-to-3' RNase H activity intrinsic to this enzyme

  12. Antiviral activity of characterized extracts from echinacea spp. (Heliantheae: Asteraceae) against herpes simplex virus (HSV-I).

    Science.gov (United States)

    Binns, S E; Hudson, J; Merali, S; Arnason, J T

    2002-09-01

    Extracts of 8 taxa of the genus Echinacea were found to have antiviral activity against Herpes simplex (HSV) virus Type I in vitro when exposed to visible and UV-A light. n-Hexane extracts of roots containing alkenes and amides were more active in general than ethyl acetate extracts containing caffeic acids. The most potent inhibitors of HSV were E. pallida var. sanguinea crude (70 % ethanol) inflorescence extract (MIC = 0.026 mg/mL), cichoric acid (MIC = 0.045 mg/mL) and Echinacea purpurea n-hexane root extract (MIC = 0.12 mg/mL).

  13. The bovine papilloma virus E1 protein has ATPase activity essential to viral DNA replication and efficient transformation in cells.

    Science.gov (United States)

    MacPherson, P; Thorner, L; Parker, L M; Botchan, M

    1994-10-01

    The bovine papilloma virus (BPV) E1 protein essential to viral DNA replication has recently been shown to associate via direct protein-DNA interactions with the viral origin of replication and to be an ATP-dependent helicase. We show here that in accordance with the latter function, the E1 gene product has intrinsic ATPase activity. Mutations placed throughout the nucleotide binding consensus element abolish the ATPase activity of E1 and render BPV genomes harboring such mutations defective for episomal replication and impaired for oncogenic transformation.

  14. Total Syntheses of (-)-Spirooliganones A and B and Their Diastereoisomers: Absolute Stereochemistry and Inhibitory Activity against Coxsackie Virus B3.

    Science.gov (United States)

    Zhao, Nan; Ren, Xiaodong; Ren, Jinhong; Lü, Haining; Ma, Shuanggang; Gao, Rongmei; Li, Yuhuan; Xu, Song; Li, Li; Yu, Shishan

    2015-06-19

    To investigate the effects of configuration on bioactivity, spirooliganones A and B and their six diastereoisomers (1-8) were synthesized in 11 steps. The key benzopyran core was assembled by intermolecular [4 + 2] hetero-Diels-Alder cycloaddition between (-)-sabinene and o-quinone methide, which was generated from the corresponding o-hydroxybenzyl alcohol. After establishing the absolute configuration, the inhibitory activities of spirooliganones 1-8 against Coxsackie virus B3 were evaluated, and the primary structure-activity relationships were analyzed. Compound 3 was the most potent compound, with an IC50 of 0.41 μM.

  15. Hemagglutinating and fusogenic activities of Newcastle disease virus: studies on receptor binding specificity and pH-induced conformational changes

    Directory of Open Access Journals (Sweden)

    E. S. S. Couceiro

    1995-08-01

    Full Text Available Vaccinal and wild strains of Newcastle Disease virus (NDV were analyzed for cell receptor binding and fusogenic biological properties associated with their HN (hemagglutinin-neuraminidase and F (fusion protein surface structures respectively. The evaluation of the biological activities of HN and F was carried out respectively by determination of hemagglutinating titers and hemolysis percentages, using erythrocytes from various animal origins at different pH values. Significant differences in hemagglutination titers for some strains of NDV were detected, when interacting with goose, sheep, guinea-pip and human "O" group erythrocytes at neutral pH. Diversity of hemolysis percentagens was observed between different NDV strains at acid pH. These analysis were developed to evaluate particular aspects of the actual influence of the receptor specifity and pH on the receptor binding and fusogenic processes of Newcastle Disease viruses.

  16. The inhibitory activity of a peptide derivative against the growth of simian immunodeficiency virus in C8166 cells.

    Science.gov (United States)

    Martin, J A; Mobberley, M A; Redshaw, S; Burke, A; Tyms, A S; Ryder, T A

    1991-04-15

    The peptide derivative Ro 31-8959 is a potent and selective inhibitor of the aspartic proteinases encoded by HIV-1 and HIV-2 and it arrests the growth of both viruses in cell culture. We have demonstrated similar effects against the simian immunodeficiency virus SIVmac251 in the human T-cell line, C8166 (ED50 = 6nM) with a therapeutic index of 4,500. The antiviral activity of Ro 31-8959 was 250 and 22 times greater than that of ddI and ddC, respectively. The mode of action was confirmed by accumulation of the polyprotein p55 with concomitant reduction of the cleavage product, p27, and by the production of immature virions.

  17. An Amphibian Host Defense Peptide Is Virucidal for Human H1 Hemagglutinin-Bearing Influenza Viruses.

    Science.gov (United States)

    Holthausen, David J; Lee, Song Hee; Kumar, Vineeth Tv; Bouvier, Nicole M; Krammer, Florian; Ellebedy, Ali H; Wrammert, Jens; Lowen, Anice C; George, Sanil; Pillai, Madhavan Radhakrishna; Jacob, Joshy

    2017-04-18

    Although vaccines confer protection against influenza A viruses, antiviral treatment becomes the first line of defense during pandemics because there is insufficient time to produce vaccines. Current antiviral drugs are susceptible to drug resistance, and developing new antivirals is essential. We studied host defense peptides from the skin of the South Indian frog and demonstrated that one of these, which we named "urumin," is virucidal for H1 hemagglutinin-bearing human influenza A viruses. This peptide specifically targeted the conserved stalk region of H1 hemagglutinin and was effective against drug-resistant H1 influenza viruses. Using electron microscopy, we showed that this peptide physically destroyed influenza virions. It also protected naive mice from lethal influenza infection. Urumin represents a unique class of anti-influenza virucide that specifically targets the hemagglutinin stalk region, similar to targeting of antibodies induced by universal influenza vaccines. Urumin therefore has the potential to contribute to first-line anti-viral treatments during influenza outbreaks. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Induction of heterosubtypic cross-protection against influenza by a whole inactivated virus vaccine: the role of viral membrane fusion activity.

    Directory of Open Access Journals (Sweden)

    Natalija Budimir

    Full Text Available BACKGROUND: The inability of seasonal influenza vaccines to effectively protect against infection with antigenically drifted viruses or newly emerging pandemic viruses underlines the need for development of cross-reactive influenza vaccines that induce immunity against a variety of virus subtypes. Therefore, potential cross-protective vaccines, e.g., whole inactivated virus (WIV vaccine, that can target conserved internal antigens such as the nucleoprotein (NP and/or matrix protein (M1 need to be explored. METHODOLOGY/PRINCIPAL FINDINGS: In the current study we show that a WIV vaccine, through induction of cross-protective cytotoxic T lymphocytes (CTLs, protects mice from heterosubtypic infection. This protection was abrogated after depletion of CD8+ cells in vaccinated mice, indicating that CTLs were the primary mediators of protection. Previously, we have shown that different procedures used for virus inactivation influence optimal activation of CTLs by WIV, most likely by affecting the membrane fusion properties of the virus. Specifically, inactivation with formalin (FA severely compromises fusion activity of the virus, while inactivation with β-propiolactone (BPL preserves fusion activity. Here, we demonstrate that vaccination of mice with BPL-inactivated H5N1 WIV vaccine induces solid protection from lethal heterosubtypic H1N1 challenge. By contrast, vaccination with FA-inactivated WIV, while preventing death after lethal challenge, failed to protect against development of disease and severe body weight loss. Vaccination with BPL-inactivated WIV, compared to FA-inactivated WIV, induced higher levels of specific CD8+ T cells in blood, spleen and lungs, and a higher production of granzyme B in the lungs upon H1N1 virus challenge. CONCLUSION/SIGNIFICANCE: The results underline the potential use of WIV as a cross-protective influenza vaccine candidate. However, careful choice of the virus inactivation procedure is important to retain membrane

  19. Induction of heterosubtypic cross-protection against influenza by a whole inactivated virus vaccine: the role of viral membrane fusion activity.

    Science.gov (United States)

    Budimir, Natalija; Huckriede, Anke; Meijerhof, Tjarko; Boon, Louis; Gostick, Emma; Price, David A; Wilschut, Jan; de Haan, Aalzen

    2012-01-01

    The inability of seasonal influenza vaccines to effectively protect against infection with antigenically drifted viruses or newly emerging pandemic viruses underlines the need for development of cross-reactive influenza vaccines that induce immunity against a variety of virus subtypes. Therefore, potential cross-protective vaccines, e.g., whole inactivated virus (WIV) vaccine, that can target conserved internal antigens such as the nucleoprotein (NP) and/or matrix protein (M1) need to be explored. In the current study we show that a WIV vaccine, through induction of cross-protective cytotoxic T lymphocytes (CTLs), protects mice from heterosubtypic infection. This protection was abrogated after depletion of CD8+ cells in vaccinated mice, indicating that CTLs were the primary mediators of protection. Previously, we have shown that different procedures used for virus inactivation influence optimal activation of CTLs by WIV, most likely by affecting the membrane fusion properties of the virus. Specifically, inactivation with formalin (FA) severely compromises fusion activity of the virus, while inactivation with β-propiolactone (BPL) preserves fusion activity. Here, we demonstrate that vaccination of mice with BPL-inactivated H5N1 WIV vaccine induces solid protection from lethal heterosubtypic H1N1 challenge. By contrast, vaccination with FA-inactivated WIV, while preventing death after lethal challenge, failed to protect against development of disease and severe body weight loss. Vaccination with BPL-inactivated WIV, compared to FA-inactivated WIV, induced higher levels of specific CD8+ T cells in blood, spleen and lungs, and a higher production of granzyme B in the lungs upon H1N1 virus challenge. The results underline the potential use of WIV as a cross-protective influenza vaccine candidate. However, careful choice of the virus inactivation procedure is important to retain membrane fusion activity and full immunogenicity of the vaccine.

  20. Using molecular imaging to assess the delivery and infection of protease activated virus in animal model of myocardial infarction

    Science.gov (United States)

    Zhu, Banghe; Guenther, Caitlin; Kwon, Sunkuk; Sevick-Muraca, Eva M.; Suh, Junghae

    2017-02-01

    Cardiovascular diseases remain the greatest cause of death in the US and gene therapy has the potential to be an effective therapy. In this study, we demonstrated MMP-9 based protease-activatable virus (PAV) for selective infection of myocardial infarct (MI) that is associated with active MMP-9 expression. To test the specificity of PAV, we used expression of a far-red fluorescence protein (iRFP) delivered by the PAV together with a dual PET/NIRF imaging agent specific for active MMP-9 activity at the site of MI in a murine model. Calibrated fluorescence imaging employed a highly-sensitive intensified camera, laser diode excitation sources, and filtration schemes based upon the spectra of iRFP and the NIRF agent. One to two days after ligation of the left anterior descending artery, the PAV or WT AAV9 virus encoding for iRFP (5x1010 genomic particles) and radiolabeled MMP-9 imaging agent (3 nmol) were injected intravenously (i.v.). PET imaging showed MMP activity was associated with adverse tissue remodeling at the site of the MI. One week after, animals were again injected i.v. with the MMP-9 agent (3 nmol) and 18-24 h later, the animals were euthanized and the hearts were harvested, sliced, and imaged for congruent iRFP transgene expression and NIRF signals associated with MMP-9 tissue activity. The fluorescent margins of iRFP and NIRF contrasted tissues were quantified in terms Standard International units of mW/cm2/sr. The sensitivity, specificity, and accuracy of PAV and WT targeting to sites of MI was determined from these calibrated fluorescence measurements. The PAV demonstrated significantly higher delivery performance than that of the WT AAV9 virus.

  1. Voltage-Dependent Anion Channel 1 Interacts with Ribonucleoprotein Complexes To Enhance Infectious Bursal Disease Virus Polymerase Activity.

    Science.gov (United States)

    Han, Chunyan; Zeng, Xiangwei; Yao, Shuai; Gao, Li; Zhang, Lizhou; Qi, Xiaole; Duan, Yulu; Yang, Bo; Gao, Yulong; Liu, Changjun; Zhang, Yanping; Wang, Yongqiang; Wang, Xiaomei

    2017-08-15

    Infectious bursal disease virus (IBDV) is a double-stranded RNA (dsRNA) virus. Segment A contains two overlapping open reading frames (ORFs), which encode viral proteins VP2, VP3, VP4, and VP5. Segment B contains one ORF and encodes the viral RNA-dependent RNA polymerase, VP1. IBDV ribonucleoprotein complexes are composed of VP1, VP3, and dsRNA and play a critical role in mediating viral replication and transcription during the virus life cycle. In the present study, we identified a cellular factor, VDAC1, which was upregulated during IBDV infection and found to mediate IBDV polymerase activity. VDAC1 senses IBDV infection by interacting with viral proteins VP1 and VP3. This association is caused by RNA bridging, and all three proteins colocalize in the cytoplasm. Furthermore, small interfering RNA (siRNA)-mediated downregulation of VDAC1 resulted in a reduction in viral polymerase activity and a subsequent decrease in viral yield. Moreover, overexpression of VDAC1 enhanced IBDV polymerase activity. We also found that the viral protein VP3 can replace segment A to execute polymerase activity. A previous study showed that mutations in the C terminus of VP3 directly influence the formation of VP1-VP3 complexes. Our immunoprecipitation experiments demonstrated that protein-protein interactions between VDAC1 and VP3 and between VDAC1 and VP1 play a role in stabilizing the interaction between VP3 and VP1, further promoting IBDV polymerase activity. IMPORTANCE The cellular factor VDAC1 controls the entry and exit of mitochondrial metabolites and plays a pivotal role during intrinsic apoptosis by mediating the release of many apoptogenic molecules. Here we identify a novel role of VDAC1, showing that VDAC1 interacts with IBDV ribonucleoproteins (RNPs) and facilitates IBDV replication by enhancing IBDV polymerase activity through its ability to stabilize interactions in RNP complexes. To our knowledge, this is the first report that VDAC1 is specifically involved in

  2. No evidence of hepatitis B virus activity in patients with anti-HBc antibody positivity with or without anti-hepatitis C virus antibody positivity.

    Science.gov (United States)

    Haushofer, Alexander C; Hauer, René; Brunner, Harald; Köller, Ursula; Trubert-Exinger, Doris; Halbmayer, Walter-Michael; Koidl, Christoph; Kessler, Harald H

    2004-04-01

    The serological pattern of anti-HBc antibody positivity without both, HBsAg and anti-HBs antibody positivity may be present in up to 4% of the population of Europe and the United States. The aim of the present study was to determine the hepatitis B virus (HBV) activity by detection of serum HBV DNA in patients with anti-HBc antibody positivity only and with confirmed anti-hepatitis C virus (anti-HCV) antibody positivity or without anti-HCV antibody positivity. A total of 141 patients positive for anti-HBc antibodies only, were investigated on serum HBV DNA load. Patients were classified into two groups: patients with confirmed positive anti-HCV antibodies (group 1) and patients without anti-HCV antibodies (group 2). Demographic data of patient groups were similar. In 66 of 70 patients with anti-HBc antibodies and anti-HCV antibodies (group 1), serum HCV RNA was detected; the remaining 4 patients were HCV RNA negative but the presence of anti-HCV antibodies was confirmed by the line probe assay. In none of the patients, with anti-HBc antibodies and without anti-HCV antibodies (group 2), serum HCV RNA was detected. In none of the patients, serum HBV DNA was detected. In this study, serum HBV DNA could not be detected in patients with anti-HBc antibodies only. There seems to be no need for determination of serum HBV DNA in patients without clinical evidence of chronic liver disease. Nevertheless, it would be useful to test patients with progressive liver disease and those, which belong to high-risk groups such as hemophiliacs, intravenous drug abusers, patients on hemodialysis, and immunocompromised patients.

  3. Gamma-irradiated influenza virus uniquely induces IFN-I mediated lymphocyte activation independent of the TLR7/MyD88 pathway.

    Directory of Open Access Journals (Sweden)

    Yoichi Furuya

    Full Text Available BACKGROUND: We have shown previously in mice, that infection with live viruses, including influenza/A and Semliki Forest virus (SFV, induces systemic partial activation of lymphocytes, characterized by cell surface expression of CD69 and CD86, but not CD25. This partial lymphocytes activation is mediated by type-I interferons (IFN-I. Importantly, we have shown that γ-irradiated SFV does not induce IFN-I and the associated lymphocyte activation. PRINCIPAL FINDINGS: Here we report that, in contrast to SFV, γ-irradiated influenza A virus elicits partial lymphocyte activation in vivo. Furthermore, we show that when using influenza viruses inactivated by a variety of methods (UV, ionising radiation and formalin treatment, as well as commercially available influenza vaccines, only γ-irradiated influenza virus is able to trigger IFN-I-dependent partial lymphocyte activation in the absence of the TLR7/MyD88 signalling pathways. CONCLUSIONS: Our data suggest an important mechanism for the recognition of γ-irradiated influenza vaccine by cytosolic receptors, which correspond with the ability of γ-irradiated influenza virus to induce cross-reactive and cross-protective cytotoxic T cell responses.

  4. Structure and behaviour of proteins, nucleic acids and viruses from vibrational Raman optical activity

    DEFF Research Database (Denmark)

    Barron, L.D.; Blanch, E.W.; McColl, I.H.

    2003-01-01

    stacking arrangement and the mutual orientation of the sugar and base rings around the C-N glycosidic link. The ROA spectra of intact viruses provide information on the folds of the coat proteins and the nucleic acid structure. The large number of structure-sensitive bands in protein ROA spectra...... is especially favourable for fold determination using pattern recognition techniques. This article gives a brief account of the ROA technique and presents the ROA spectra of a selection of proteins, nucleic acids and viruses that illustrate the applications of ROA spectroscopy in biomolecular research....

  5. Hepatitis C virus core protein regulates p300/CBP co-activation function. Possible role in the regulation of NF-AT1 transcriptional activity

    International Nuclear Information System (INIS)

    Gomez-Gonzalo, Marta; Benedicto, Ignacio; Carretero, Marta; Lara-Pezzi, Enrique; Maldonado-Rodriguez, Alejandra; Moreno-Otero, Ricardo; Lai, Michael M.C.; Lopez-Cabrera, Manuel

    2004-01-01

    Hepatitis C virus (HCV) core is a viral structural protein; it also participates in some cellular processes, including transcriptional regulation. However, the mechanisms of core-mediated transcriptional regulation remain poorly understood. Oncogenic virus proteins often target p300/CBP, a known co-activator of a wide variety of transcription factors, to regulate the expression of cellular and viral genes. Here we demonstrate, for the first time, that HCV core protein interacts with p300/CBP and enhances both its acetyl-transferase and transcriptional activities. In addition, we demonstrate that nuclear core protein activates the NH 2 -terminal transcription activation domain (TAD) of NF-AT1 in a p300/CBP-dependent manner. We propose a model in which core protein regulates the co-activation function of p300/CBP and activates NF-AT1, and probably other p300/CBP-regulated transcription factors, by a novel mechanism involving the regulation of the acetylation state of histones and/or components of the transcriptional machinery

  6. Influenza virus-induced alterations of cytochrome P-450 enzyme activities following exposure of mice to coal and diesel particulates

    Energy Technology Data Exchange (ETDEWEB)

    Rabovsky, J.; Judy, D.J.; Rodak, D.J.; Petersen, M.

    1986-06-01

    We have investigated a relationship between two detoxication systems, metabolic detoxication through the cytochrome P-450 (P-450) pathway and resistance to infection through interferon (IFN), in mice infected with influenza virus following exposure to coal dust (CD) and diesel exhaust (DE) particulates. Mice were exposed by inhalation to filtered air (FA; control), CD, or DE for 1 month and then inoculated intranasally (IN) with influenza virus. During infection, 7-ethoxycoumarin deethylase (7ECdeEt'ase) and ethylmorphine demethylase (EMdeMe'ase) (monooxygenases), and NADPH cytochrome c reductase (NADPH c red'ase) were measured in liver microsomes. Temporal patterns of enzyme activities were observed with control animals. EMdeMe'ase and NADPH c red'ase exhibited peak values at Day 4 postinfection (27.6 and 482 nmole/min/mg protein, respectively), compared to initial activities (9.1 and 307 nmole/min/mg protein, respectively). 7ECdeEt'ase activity decreased between Days 1-3 postvirus infection and thereafter returned to the original value (1.7 nmole/min/mg protein). When the mice were first exposed to CD or DE particulates for 1 month prior to influenza infection, changes in enzyme temporal patterns were observed. The increased EMdeMe'ase activity at Day 4 was not observed in mice exposed to CD and was reduced in mice exposed to DE. Preexposure to either particulate resulted in the abolition of the increased Day 4 activity of NADPH c red'ase. The 7ECdeEt'ase postinfection temporal pattern was not affected by a preexposure to either particulate. Estimates of the enzyme activities after the 1-month exposure to FA, CD, or DE but before virus infection indicated no changes due to particulate exposure alone. Under conditions of particulate exposure and virus infection, serum IFN levels peaked at Days 4-5 and were unaffected by the 1-month preexposure to CD or DE.

  7. Influenza virus-induced alterations of cytochrome P-450 enzyme activities following exposure of mice to coal and diesel particulates.

    Science.gov (United States)

    Rabovsky, J; Judy, D J; Rodak, D J; Petersen, M

    1986-06-01

    We have investigated a relationship between two detoxication systems, metabolic detoxication through the cytochrome P-450 (P-450) pathway and resistance to infection through interferon (IFN), in mice infected with influenza virus following exposure to coal dust (CD) and diesel exhaust (DE) particulates. Mice were exposed by inhalation to filtered air (FA; control), CD, or DE for 1 month and then inoculated intranasally (IN) with influenza virus. During infection, 7-ethoxycoumarin deethylase (7ECdeEt'ase) and ethylmorphine demethylase (EMdeMe'ase) (monooxygenases), and NADPH cytochrome c reductase (NADPH c red'ase) were measured in liver microsomes. Temporal patterns of enzyme activities were observed with control animals. EMdeMe'ase and NADPH c red'ase exhibited peak values at Day 4 postinfection (27.6 and 482 nmole/min/mg protein, respectively), compared to initial activities (9.1 and 307 nmole/min/mg protein, respectively). 7ECdeEt'ase activity decreased between Days 1-3 postvirus infection and thereafter returned to the original value (1.7 nmole/min/mg protein). When the mice were first exposed to CD or DE particulates for 1 month prior to influenza infection, changes in enzyme temporal patterns were observed. The increased EMdeMe'ase activity at Day 4 was not observed in mice exposed to CD and was reduced in mice exposed to DE. Preexposure to either particulate resulted in the abolition of the increased Day 4 activity of NADPH c red'ase. The 7ECdeEt'ase postinfection temporal pattern was not affected by a preexposure to either particulate. Estimates of the enzyme activities after the 1-month exposure to FA, CD, or DE but before virus infection indicated no changes due to particulate exposure alone. Under these conditions of particulate exposure and virus infection, serum IFN levels in the mice used in this study peaked at Days 4-5 and were unaffected by the 1-month preexposure to CD or DE (Hahon et al., (1985). The data suggest the relationship that exists

  8. High antiviral effects of hibiscus tea extract on the H5 subtypes of low and highly pathogenic avian influenza viruses.

    Science.gov (United States)

    Baatartsogt, Tugsbaatar; Bui, Vuong N; Trinh, Dai Q; Yamaguchi, Emi; Gronsang, Dulyatad; Thampaisarn, Rapeewan; Ogawa, Haruko; Imai, Kunitoshi

    2016-10-01

    Viral neuraminidase inhibitors are widely used as synthetic anti-influenza drugs for the prevention and treatment of influenza. However, drug-resistant influenza A virus variants, including H5N1 highly pathogenic avian influenza viruses (HPAIVs), have been reported. Therefore, the discovery of novel and effective antiviral agents is warranted. We screened the antiviral effects of 11 herbal tea extracts (hibiscus, black tea, tencha, rosehip tea, burdock tea, green tea, jasmine tea, ginger tea, lavender tea, rose tea and oak tea) against the H5N1 HPAIV in vitro. Among the tested extracts, only the hibiscus extract and its fractionated extract (frHibis) highly and rapidly reduced the titers of all H5 HPAIVs and low pathogenic AIVs (LPAIVs) used in the pre-treatment tests of Madin-Darby canine kidney (MDCK) cells that were inoculated with a mixture of the virus and the extract. Immunogold electron microscopy showed that anti-H5 monoclonal antibodies could not bind to the deformed H5 virus particles pretreated with frHibis. In post-treatment tests of MDCK cells cultured in the presence of frHibis after infection with H5N1 HPAIV, the frHibis inhibited viral replication and the expression of viral antigens and genes. Among the plants tested, hibiscus showed the most prominent antiviral effects against both H5 HPAIV and LPAIV.

  9. Mutations during the Adaptation of H9N2 Avian Influenza Virus to the Respiratory Epithelium of Pigs Enhance Sialic Acid Binding Activity and Virulence in Mice.

    Science.gov (United States)

    Yang, W; Punyadarsaniya, D; Lambertz, R L O; Lee, D C C; Liang, C H; Höper, D; Leist, S R; Hernández-Cáceres, A; Stech, J; Beer, M; Wu, C Y; Wong, C H; Schughart, K; Meng, F; Herrler, G

    2017-04-15

    The natural reservoir for influenza viruses is waterfowl, and from there they succeeded in crossing the barrier to different mammalian species. We analyzed the adaptation of avian influenza viruses to a mammalian host by passaging an H9N2 strain three times in differentiated swine airway epithelial cells. Using precision-cut slices from the porcine lung to passage the parental virus, isolates from each of the three passages (P1 to P3) were characterized by assessing growth curves and ciliostatic effects. The only difference noted was an increased growth kinetics of the P3 virus. Sequence analysis revealed four mutations: one each in the PB2 and NS1 proteins and two in the HA protein. The HA mutations, A190V and T212I, were characterized by generating recombinant viruses containing either one or both amino acid exchanges. Whereas the parental virus recognized α2,3-linked sialic acids preferentially, the HA190 mutant bound to a broad spectrum of glycans with α2,6/8/9-linked sialic acids. The HA212 mutant alone differed only slightly from the parental virus; however, the combination of both mutations (HA190+HA212) increased the binding affinity to those glycans recognized by the HA190 mutant. Remarkably, only the HA double mutant showed a significantly increased pathogenicity in mice. In contrast, none of those mutations affected the ciliary activity of the epithelial cells which is characteristic for virulent swine influenza viruses. Taken together, our results indicate that shifts in the HA receptor affinity are just an early adaptation step of avian H9N2 strains; further mutational changes may be required to become virulent for pigs. IMPORTANCE Swine play an important role in the interspecies transmission of influenza viruses. Avian influenza A viruses (IAV) of the H9N2 subtype have successfully infected hosts from different species but have not established a stable lineage. We have analyzed the adaptation of IAV-H9N2 virus to target cells of a new host by

  10. Ebola Virus and Marburg Virus

    Science.gov (United States)

    Ebola virus and Marburg virus Overview Ebola virus and Marburg virus are related viruses that cause hemorrhagic fevers — illnesses marked by severe bleeding (hemorrhage), organ failure and, in many ...

  11. Inhibition of tobacco mosaic virus replication in lateral roots is dependent on an activated meristem-derived signal.

    Science.gov (United States)

    Valentine, T A; Roberts, I M; Oparka, K J

    2002-05-01

    Viral invasion of the root system of Nicotiana benthamiana was studied noninvasively with a tobacco mosaic virus (TMV) vector expressing the green-fluorescent protein (GFP). Lateral root primordia, which developed from the pericycle of primary roots, became heavily infected as they emerged from the root cortex. However, following emergence, a progressive wave of viral inhibition occurred that originated in the lateral-root meristem and progressed towards its base. Excision of source and sink tissues suggested that the inhibition of virus replication was brought about by the basipetal movement of a root meristem signal. When infected plants were inoculated with tobacco rattle virus (TRV) expressing the red-fluorescent protein, DsRed, TRV entered the lateral roots and suppressed the host response, leading to a reestablishment of TMV infection in lateral roots. By infecting GFP-expressing transgenic plants with TMV carrying the complementary GFP sequence it was possible to silence the host GFP, leading to the complete loss of fluorescence in lateral roots. The data suggest that viral inhibition in lateral roots occurs by a gene-silencing-like mechanism that is dependent on the activation of a lateral-root meristem.

  12. Computer-aided identification, design and synthesis of a novel series of compounds with selective antiviral activity against chikungunya virus.

    Science.gov (United States)

    Bassetto, Marcella; De Burghgraeve, Tine; Delang, Leen; Massarotti, Alberto; Coluccia, Antonio; Zonta, Nicola; Gatti, Valerio; Colombano, Giampiero; Sorba, Giovanni; Silvestri, Romano; Tron, Gian Cesare; Neyts, Johan; Leyssen, Pieter; Brancale, Andrea

    2013-04-01

    Chikungunya virus (CHIKV) is an Arbovirus that is transmitted to humans primarily by the mosquito species Aedes aegypti. Infection with this pathogen is often associated with fever, rash and arthralgia. Neither a vaccine nor an antiviral drug is available for the prevention or treatment of this disease. Albeit considered a tropical pathogen, adaptation of the virus to the mosquito species Aedes albopictus, which is also very common in temperate zones, has resulted in recent outbreaks in Europe and the US. In the present study, we report on the discovery of a novel series of compounds that inhibit CHIKV replication in the low μM range. In particular, we initially performed a virtual screening simulation of ∼5 million compounds on the CHIKV nsP2, the viral protease, after which we investigated and explored the Structure-Activity Relationships of the hit identified in silico. Overall, a series of 26 compounds, including the original hit, was evaluated in a virus-cell-based CPE reduction assay. The study of such selective inhibitors will contribute to a better understanding of the CHIKV replication cycle and may represents a first step towards the development of a clinical candidate drug for the treatment of this disease. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Structure of unliganded HSV gD reveals a mechanism for receptor-mediated activation of virus entry

    Energy Technology Data Exchange (ETDEWEB)

    Krummenacher, Claude; Supekar, Vinit M.; Whitbeck, J. Charles; Lazear, Eric; Connolly, Sarah A.; Eisenberg, Roselyn J.; Cohen, Gary H.; Wiley, Don C.; Carfi, Andrea (UPENN); (IRBM); (CHLMM)

    2010-07-19

    Herpes simplex virus (HSV) entry into cells requires binding of the envelope glycoprotein D (gD) to one of several cell surface receptors. The 50 C-terminal residues of the gD ectodomain are essential for virus entry, but not for receptor binding. We have determined the structure of an unliganded gD molecule that includes these C-terminal residues. The structure reveals that the C-terminus is anchored near the N-terminal region and masks receptor-binding sites. Locking the C-terminus in the position observed in the crystals by an intramolecular disulfide bond abolished receptor binding and virus entry, demonstrating that this region of gD moves upon receptor binding. Similarly, a point mutant that would destabilize the C-terminus structure was nonfunctional for entry, despite increased affinity for receptors. We propose that a controlled displacement of the gD C-terminus upon receptor binding is an essential feature of HSV entry, ensuring the timely activation of membrane fusion.

  14. Relationship between enhanced macrophage phagocytic activity and the induction of interferon by Newcastle disease virus in mice.

    Science.gov (United States)

    Hamburg, S I; Cassell, G H; Rabinovitch, M

    1980-03-01

    The relationship between phagocytic activity of peritoneal macrophages and serum interferon (IF) titers was evaluated in mice challenged with Newcastle disease virus (NDV). Time course studies indicated peak serum IF titers between 6 and 12 hr, whereas Fc receptor-mediated macrophage phagocytosis was maximal 18 hr after viral administration. Both responses decreased in parallel as the inoculated dose of the virus was reduced. Splenectomy, shown by others to decrease the NDV-induced serum IF titers, significantly decreased the stimulation of phagocytosis. The role of T cells in the response to the virus was studied with nude mice raised under germfree conditions. NDV-induced serum IF titers and macrophage phagocytosis were both diminished in BALB/c nudes compared with their heterozygous littermates. Both responses could be partially restored by transfer of thymocytes obtained from heterozygous mice. The results provide further evidence that in vivo macrophage stimulation by NDV is mediated by induced IF. The experiments with nude mice also indicate that the IF response to NDV is regulated by T lymphocytes.

  15. The P0 gene of Sugarcane yellow leaf virus encodes an RNA silencing suppressor with unique activities

    International Nuclear Information System (INIS)

    Mangwende, Tichaona; Wang Mingli; Borth, Wayne; Hu, John; Moore, Paul H.; Mirkov, T. Erik; Albert, Henrik H.

    2009-01-01

    The Sugarcane yellow leaf virus (SCYLV) P0, a member of the highly heterologous proteins of poleroviruses, is a suppressor of posttranscriptional gene silencing (PTGS) and has additional activities not seen in other P0 proteins. The P0 protein in previously tested poleroviruses (Beet western yellows virus and Cucurbit aphid-borne yellows virus), suppresses local, but not systemic, PTGS induced by both sense GFP and inverted repeat GF using its F-box-like domain to mediate destabilization of the Argonaute1 protein. We now report that the SCYLV P0 protein not only suppressed local PTGS induced by sense GFP and inverted repeat GF in Nicotiana benthamiana, but also triggered a dosage dependent cell death phenotype in infiltrated leaves and suppressed systemic sense GFP-PTGS. Deletion of the first 15 N-terminal amino acid residues of SCYLV P0 abolished suppression of both local and systemic PTGS and the induction of cell death. In contrast, only systemic PTGS and cell death were lost when the 15 C-terminal amino acid residues were deleted. We conclude that the 15 C-terminal amino acid residue region of SCYLV P0 is necessary for suppressing systemic PTGS and inducing cell death, but is not required for suppression of local PTGS

  16. Activation of Cyclic Adenosine Monophosphate Pathway Increases the Sensitivity of Cancer Cells to the Oncolytic Virus M1.

    Science.gov (United States)

    Li, Kai; Zhang, Haipeng; Qiu, Jianguang; Lin, Yuan; Liang, Jiankai; Xiao, Xiao; Fu, Liwu; Wang, Fang; Cai, Jing; Tan, Yaqian; Zhu, Wenbo; Yin, Wei; Lu, Bingzheng; Xing, Fan; Tang, Lipeng; Yan, Min; Mai, Jialuo; Li, Yuan; Chen, Wenli; Qiu, Pengxin; Su, Xingwen; Gao, Guangping; Tai, Phillip W L; Hu, Jun; Yan, Guangmei

    2016-02-01

    Oncolytic virotherapy is a novel and emerging treatment modality that uses replication-competent viruses to destroy cancer cells. Although diverse cancer cell types are sensitive to oncolytic viruses, one of the major challenges of oncolytic virotherapy is that the sensitivity to oncolysis ranges among different cancer cell types. Furthermore, the underlying mechanism of action is not fully understood. Here, we report that activation of cyclic adenosine monophosphate (cAMP) signaling significantly sensitizes refractory cancer cells to alphavirus M1 in vitro, in vivo, and ex vivo. We find that activation of the cAMP signaling pathway inhibits M1-induced expression of antiviral factors in refractory cancer cells, leading to prolonged and severe endoplasmic reticulum (ER) stress, and cell apoptosis. We also demonstrate that M1-mediated oncolysis, which is enhanced by cAMP signaling, involves the factor, exchange protein directly activated by cAMP 1 (Epac1), but not the classical cAMP-dependent protein kinase A (PKA). Taken together, cAMP/Epac1 signaling pathway activation inhibits antiviral factors and improves responsiveness of refractory cancer cells to M1-mediated virotherapy.

  17. RIG-I-like receptor activation by dengue virus drives follicular T helper cell formation and antibody production.

    Directory of Open Access Journals (Sweden)

    Joris K Sprokholt

    2017-11-01

    Full Text Available Follicular T helper cells (TFH are fundamental in orchestrating effective antibody-mediated responses critical for immunity against viral infections and effective vaccines. However, it is unclear how virus infection leads to TFH induction. We here show that dengue virus (DENV infection of human dendritic cells (DCs drives TFH formation via crosstalk of RIG-I-like receptor (RLR RIG-I and MDA5 with type I Interferon (IFN signaling. DENV infection leads to RLR-dependent IKKε activation, which phosphorylates IFNα/β receptor-induced STAT1 to drive IL-27 production via the transcriptional complex ISGF3. Inhibiting RLR activation as well as neutralizing antibodies against IL-27 prevented TFH formation. DENV-induced CXCR5+PD-1+Bcl-6+ TFH cells secreted IL-21 and activated B cells to produce IgM and IgG. Notably, RLR activation by synthetic ligands also induced IL-27 secretion and TFH polarization. These results identify an innate mechanism by which antibodies develop during viral disease and identify RLR ligands as potent adjuvants for TFH-promoting vaccination strategies.

  18. Supercritical fluid extraction of heather (Calluna vulgaris) and evaluation of anti-hepatitis C virus activity of the extracts.

    Science.gov (United States)

    García-Risco, Mónica Rodriguez; Vázquez, Erika; Sheldon, Julie; Steinmann, Eike; Riebesehl, Nina; Fornari, Tiziana; Reglero, Guillermo

    2015-02-16

    Previous studies using lipid extracts of heather (Calluna vulgaris) leaves showed the presence of high concentrations of ursolic and oleanolic acid. These two compounds have been reported to present antiviral activity against hepatitis C virus (HCV). In this work, the supercritical fluid extraction of heather was studied with the aim of assessing a potential anti-HCV activity of the extracts owing to their triterpenic acid content. Supercritical extraction assays were carried out exploring the pressure range of 20-50 MPa, temperatures of 40-70°C and 0-15% of ethanol cosolvent. The content of oleanolic and ursolic acid in the extracts were determined, and different samples were screened for cellular cytotoxicity and virus inhibition using a HCV cell culture infection system. Antiviral activity was observed in most extracts. In general, superior anti-HCV activity was observed for higher contents of oleanolic and ursolic acids in the extracts. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Enhanced insecticidal activity of Chilo iridescent virus expressing an insect specific neurotoxin

    NARCIS (Netherlands)

    Nalcacioglu, Remziye; Muratoglu, Hacer; Yesilyurt, Aydın; Oers, van Monique M.; Vlak, Just M.; Demirbag, Zihni

    2016-01-01

    Previously we have generated a recombinant Chilo iridescent virus (CIV) by inserting the green fluorescent protein gene (gfp) into the CIV 157L open reading frame (ORF) locus and showed that this recombinant (rCIV-Δ157L-gfp) was fully infectious both in cell culture as well as in insect larvae.

  20. Quantifying antiviral activity optimizes drug combinations against hepatitis C virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, Yoshiki [School of Medicine, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Ishikawa, Japan; Nakajim, Syo [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan; Department of Applied Biological Sciences, Faculty of Science and Technology, Tokyo University of Sciences, Chiba, J; Ohash, Hirofumi [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan: Department of Applied Biological Sciences, Faculty of Science and Technology, Tokyo University of Sciences, Chiba, J; Tanaka, Yasuhito [Department of Virology and Liver Unit, Nagoya City University Graduate School of Medicinal Sciences, Nagoya, Japan; Wakita, Takaji [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan; Perelson, Alan S. [Los Alamos National Laboratory; Iwami, Shingo [Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan: PRESTO, JST, Saitama, Japan: CREST, JST, Saitama, Japan; Watashi, Koichi [Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan: Department of Applied Biological Sciences, Faculty of Science and Technology, Tokyo University of Sciences, Chiba, J

    2016-03-21

    Cell culture study combing a mathematical model and computer simulation quantifies the anti-hepatitis C virus drug efficacy at any concentrations and any combinations in preclinical settings, and can obtain rich basic evidences for selecting optimal treatments prior to costly clinical trials.

  1. Sphingolipids activate membrane fusion of Semliki Forest virus in a stereospecific manner

    DEFF Research Database (Denmark)

    Moesby, Lise; Corver, J; Erukulla, R K

    1995-01-01

    The alphavirus Semliki Forest virus (SFV) enters cells through receptor-mediated endocytosis. Subsequently, triggered by the acid pH in endosomes, the viral envelope fuses with the endosomal membrane. Membrane fusion of SFV has been shown previously to be dependent on the presence of cholesterol ...

  2. New in vitro method for evaluating antiviral activity of acyclic nucleoside phosphonates against plant viruses

    Czech Academy of Sciences Publication Activity Database

    Špak, Josef; Holý, Antonín; Pavingerová, Daniela; Votruba, Ivan; Špaková, Vlastimila; Petrzik, Karel

    2010-01-01

    Roč. 88, č. 3 (2010), s. 296-303 ISSN 0166-3542 R&D Projects: GA ČR GA522/09/0707 Institutional research plan: CEZ:AV0Z50510513; CEZ:AV0Z40550506 Keywords : Brassica * Chemotherapy * Turnip yellow mosaic virus * Ribavirin Subject RIV: CE - Biochemistry Impact factor: 4.439, year: 2010

  3. Activities of Different Classes of Acyclic Nucleoside Phosphonates against BK Virus in Primary Human Renal Cells

    Czech Academy of Sciences Publication Activity Database

    Topalis, D.; Lebeau, I.; Krečmerová, Marcela; Andrei, G.; Snoeck, R.

    2011-01-01

    Roč. 55, č. 5 (2011), s. 1961-1967 ISSN 0066-4804 Institutional research plan: CEZ:AV0Z40550506 Keywords : polyomavirus * BK virus * nephropathy * acyclic nucleoside phosphonates * HPMP-5-azaC Subject RIV: CC - Organic Chemistry Impact factor: 4.841, year: 2011

  4. Discovery of novel cyclic peptide inhibitors of dengue virus NS2B-NS3 protease with antiviral activity.

    Science.gov (United States)

    Takagi, Youhei; Matsui, Kouhei; Nobori, Haruaki; Maeda, Haruka; Sato, Akihiko; Kurosu, Takeshi; Orba, Yasuko; Sawa, Hirofumi; Hattori, Kazunari; Higashino, Kenichi; Numata, Yoshito; Yoshida, Yutaka

    2017-08-01

    NS2B-NS3 protease is an essential enzyme for the replication of dengue virus (DENV), which continues to be a serious threat to worldwide public health. We designed and synthesized a series of cyclic peptides mimicking the substrates of this enzyme, and assayed their activity against the DENV-2 NS2B-NS3 protease. The introduction of aromatic residues at the appropriate positions and conformational restriction generated the most promising cyclic peptide with an IC 50 of 0.95μM against NS2B-NS3 protease. Cyclic peptides with proper positioning of additional arginines and aromatic residues exhibited antiviral activity against DENV. Furthermore, replacing the C-terminal amide bond of the polybasic amino acid sequence with an amino methylene moiety stabilized the cyclic peptides against hydrolysis by NS2B-NS3 protease, while maintaining their enzyme inhibitory activity and antiviral activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Comparison of the Histological and Serological Parameters of Patients with Hepatitis Delta Virus in Active and Inactive Hepatitis B Virus Carriers

    International Nuclear Information System (INIS)

    Shaikh, S.; Ram, D. B.; Talpur, A.; Tanveer, S.

    2014-01-01

    Objective: To assess the histological and serological parameters of patients with hepatitis delta virus (HDV) in active HBV versus inactive HBV carriers. Study Design: An observational study. Place and Duration of Study: Medical Unit IV at Liaquat University Hospital, Jamshoro, Sindh, from June 2008 to September 2011. Methodology: This study included 49 consecutive inactive HBV carriers who were HBsAg-positive, HBV DNA-negative, anti-D antibody-positive, and HDV RNA-positive, as well as 277 patients with active HBV who were HBsAg-positive, anti- HDV antibody-positive, HDV RNA-positive, and demonstrated > 20,000 IU/mL HBV DNA and > 2 (ULN) serum glutamic pyruvic transaminase (SGPT). Informed consent was obtained from each patient. Liver biopsies were obtained and the staging of fibrosis was performed according to the METAVIR scoring system. Continuous variables such as age, SGPT, platelet count, and the HBV DNA level were computed as the mean A +- standard deviation. Categorical variables such as gender and stage of fibrosis are expressed as percentages. All data were processed using SPSS version 16. Results: This study included 49 patients in an inactive HBV group. Fibrosis stage 0 was observed in 37 (75.5%) patients and 12 (24.5%) were stage 1. Among the 277 patients with active disease, fibrosis stage 0 was present in 7 (2.5%) patients, stage 1 in 31 (11.2%) patients, stage 2 in 172 (62.1%) patients, stage 3 in 44 (15.9%) patients and stage 4 in 23 (8.3%) patients. Conclusion: HDV in active HBV carriers is severe on its initial presentation and requires prompt treatment whereas in inactive HBV carriers demonstrates an indolent course. (author)

  6. The physical activity levels among people living with human immunodeficiency virus/acquired immunodeficiency syndrome receiving high active antiretroviral therapy in Rwanda.

    Science.gov (United States)

    Frantz, J M; Murenzi, A

    2013-01-01

    The accessibility of high active antiretroviral therapy (HAART) for local human immunodeficiency virus (HIV) patients is improving in Rwanda. It is well known that this therapy is associated with serious adverse effects, such as metabolic and morphologic changes. One of the recommended preventive modalities for these complications is participation in physical activity. The current study aims to determine the anthropometric profile and physical activity levels among people living with HIV and receiving HAART in Kigali, Rwanda. The study was a cross-sectional, descriptive quantitative survey. The participant's levels of physical activity participation and their association with anthropometric profiles were measured, using a structured self-administered questionnaire for 407 clients passing through the clinics. Of the participants, approximately 70% were inactive and in addition, 40% were obese and 43% overweight. Obesity was found to be strongly associated with inactivity. Lack of motivation, and time as well as fear of worsening the disease were found to be barriers to participation in physical activity.

  7. [Protective activity of Immunovac-VP-4 vaccine against avian influenza virus H5N2 administered by different methods].

    Science.gov (United States)

    Egorova, N B; Kurbatova, E A; Akhmatova, N K; Semenova, I B

    2011-01-01

    To experimentally assess protective effect of Immunovac-VP-4 vaccine against avian influenza virus H5N2. MATERIALS AND METHODS. Immunization of mice with polycomponent vaccine Immunovac-VP-4 was performed using oral or mucosal route of administration (intranasally, orally, and with combined nasal-oral method). Immunized mice were inoculated intranasally by influenza virus H5N2 adapted for mice. Survival of mice in experimental and control (intact) groups was assessed daily during 14 days. Survival and death rates of mice were determined. Levels of cytokines in sera of mice from both groups were measured by enzyme immunoassay. Half of experimental animals survived after triple subcutaneous administration of vaccine in dose 20 mcg and subsequent intranasal challenge with avian influenza virus H5N2. Single subcutaneous immunization with dose 400 mcg resulted in survival of 80 +/- 12.6% of mice after challenge. Triple intranasal and combined intranasal-oral immunization as well as after triple subcutaneous immunization resulted in survival of half of challenged mice. In control group challenge was lethal for 90 - 100% of mice. Same methods of immunization lead to increase of IL-6, IL-12, IL-15, and IFN-gamma levels. Data about significant protective effect after immunization with Immunovac-VP-4 against avian influenza virus H5N2 were obtained. Immunovac-VP-4 administered by mentioned routes activated nasal-associated lymphoid tissue providing first line defense at entry site of influenza infection, which demonstrates need to further study of this vaccine during development of strategy for non-specific prophylaxis of influenza infection.

  8. Activity of aphids associated with lettuce and broccoli in Spain and their efficiency as vectors of Lettuce mosaic virus.

    Science.gov (United States)

    Nebreda, M; Moreno, A; Pérez, N; Palacios, I; Seco-Fernández, V; Fereres, A

    2004-03-01

    This research sought to identify the aphid virus vector species associated with lettuce and broccoli crops in Spain, and to determine their population dynamics and ability to transmit Lettuce mosaic virus (LMV). Green tile traps and Moericke yellow water-pan traps were used to monitor aphid flights during the spring and autumn growing seasons of 2001. Aphid species feeding on lettuce were counted weekly. The transmission efficiencies of LMV were determined for the aphid species caught most frequently. The Moericke traps generally caught more aphid species than the tile trap, but the latter was the most suitable to estimate flight activity of species involved in virus spread. Spring aphid catches indicated that the main aphid species landing on lettuce in the regions of Madrid and Murcia was Hyperomyzus lactucae, but Brachycaudus helichrysi was also abundant in both regions. In broccoli in the Navarra region, the most abundant species in spring were Aphis fabae, B. helichrysi and H. lactucae. In autumn-sown crops, the main species landing on lettuce in the Madrid region were Hyadaphis coriandri and Aphis spiraecola. In Murcia, A. spiraecola and Myzus persicae were the most abundant, while in Navarra, Therioaphis trifolii, and various Aphis spp. were the most numerous landing on broccoli. The main aphid species colonising lettuce was Nasonovia ribisnigri, but other less abundant colonising species were Aulacorthum solani and Macrosiphum euphorbiae. The most efficient vectors of LMV were M. persicae, Aphis gossypii and M. euphorbiae, while A. fabae and H. lactucae transmitted with low efficiency, and Rhopalosiphum padi and N. ribisnigri did not transmit. Occurrence of LMV epidemics in central Spain in relation to aphid flights and the role of weeds as virus reservoirs is discussed.

  9. Long Terminal Repeat Circular DNA as Markers of Active Viral Replication of Human T Lymphotropic Virus-1 in Vivo

    Directory of Open Access Journals (Sweden)

    James M Fox

    2016-03-01

    Full Text Available Clonal expansion of human T-lymphotropic virus type-1 (HTLV-1 infected cells in vivo is well documented. Unlike human immunodeficiency virus type 1 (HIV-1, HTLV-1 plasma RNA is sparse. The contribution of the “mitotic” spread of HTLV-1 compared with infectious spread of the virus to HTLV-1 viral burden in established infection is uncertain. Since extrachromosomal long terminal repeat (LTR DNA circles are indicators of viral replication in HIV-1 carriers with undetectable plasma HIV RNA, we hypothesised that HTLV-1 LTR circles could indicate reverse transcriptase (RT usage and infectious activity. 1LTR and 2LTR DNA circles were measured in HTLV-1 cell lines and peripheral blood mononuclear cells (PBMC of asymptomatic carriers (ACs and patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP or adult T cell leukaemia/lymphoma (ATLL. 1LTR DNA circles were detected in 14/20 patients at a mean of 1.38/100 PBMC but did not differentiate disease status nor correlate with HTLV-1 DNA copies. 2LTR DNA circles were detected in 30/31 patients and at higher concentrations in patients with HTLV-1-associated diseases, independent of HTLV-1 DNA load. In an incident case the 2LTR DNA circle concentration increased 2.1 fold at the onset of HAM/TSP compared to baseline. Detectable and fluctuating levels of HTLV-1 DNA circles in patients indicate viral RT usage and virus replication. Our results indicate HTLV-1 viral replication capacity is maintained in chronic infection and may be associated with disease onset.

  10. Binding of human papilloma virus L1 virus-like particles to dendritic cells is mediated through heparan sulfates and induces immune activation

    NARCIS (Netherlands)

    de Witte, Lot; Zoughlami, Younes; Aengeneyndt, Birgit; David, Guido; van Kooyk, Yvette; Gissmann, Lutz; Geijtenbeek, Teunis B. H.

    2007-01-01

    Immunization using human papilloma virus (HPV)-L1 virus-like particles (VLPs) induces a robust and effective immune response, which has recently resulted in the implementation of the HPV-L1 VLP vaccination in health programs. However, during infection, HPV can escape immune surveillance leading to

  11. In Vitro Activation of the IκB Kinase Complex by Human T-cell Leukemia Virus Type-1 Tax*

    Science.gov (United States)

    Mukherjee, Sohini; Negi, Veera S.; Keitany, Gladys; Tanaka, Yuetsu; Orth, Kim

    2008-01-01

    Human T-cell leukemia virus type-I expresses Tax, a 40-kDa oncoprotein that activates IκB kinase (IKK), resulting in constitutive activation of NFκB. Herein, we have developed an in vitro signaling assay to analyze IKK complex activation by recombinant Tax. Using this assay in combination with reporter assays, we demonstrate that Tax-mediated activation of IKK is independent of phosphatases. We show that sustained activation of the Tax-mediated activation of the NFκB pathway is dependent on an intact Hsp90-IKK complex. By acetylating and thereby preventing activation of the IKK complex by the Yersinia effector YopJ, we demonstrate that Tax-mediated activation of the IKK complex requires a phosphorylation step. Our characterization of an in vitro signaling assay system for the mechanism of Tax-mediated activation of the IKK complex with a variety of mutants and inhibitors results in a working model for the biochemical mechanism of Tax-induced activation. PMID:18223255

  12. Hepatitis C Virus Indirectly Disrupts DNA Damage-Induced p53 Responses by Activating Protein Kinase R

    Directory of Open Access Journals (Sweden)

    Jonathan K. Mitchell

    2017-04-01

    Full Text Available Many DNA tumor viruses promote cellular transformation by inactivating the critically important tumor suppressor protein p53. In contrast, it is not known whether p53 function is disrupted by hepatitis C virus (HCV, a unique, oncogenic RNA virus that is the leading infectious cause of liver cancer in many regions of the world. Here we show that HCV-permissive, liver-derived HepG2 cells engineered to constitutively express microRNA-122 (HepG2/miR-122 cells have normal p53-mediated responses to DNA damage and that HCV replication in these cells potently suppresses p53 responses to etoposide, an inducer of DNA damage, or nutlin-3, an inhibitor of p53 degradation pathways. Upregulation of p53-dependent targets is consequently repressed within HCV-infected cells, with potential consequences for cell survival. Despite this, p53 function is not disrupted by overexpression of the complete HCV polyprotein, suggesting that altered p53 function may result from the host response to viral RNA replication intermediates. Clustered regularly interspaced short palindromic repeat (CRISPR/Cas9-mediated ablation of double-stranded RNA (dsRNA-activated protein kinase R (PKR restored p53 responses while boosting HCV replication, showing that p53 inhibition results directly from viral activation of PKR. The hepatocellular abundance of phosphorylated PKR is elevated in HCV-infected chimpanzees, suggesting that PKR activation and consequent p53 inhibition accompany HCV infection in vivo. These findings reveal a feature of the host response to HCV infection that may contribute to hepatocellular carcinogenesis.

  13. A whole virus pandemic influenza H1N1 vaccine is highly immunogenic and protective in active immunization and passive protection mouse models.

    Directory of Open Access Journals (Sweden)

    Otfried Kistner

    Full Text Available The recent emergence and rapid spread of a novel swine-derived H1N1 influenza virus has resulted in the first influenza pandemic of this century. Monovalent vaccines have undergone preclinical and clinical development prior to initiation of mass immunization campaigns. We have carried out a series of immunogenicity and protection studies following active immunization of mice, which indicate that a whole virus, nonadjuvanted vaccine is immunogenic at low doses and protects against live virus challenge. The immunogenicity in this model was comparable to that of a whole virus H5N1 vaccine, which had previously been demonstrated to induce high levels of seroprotection in clinical studies. The efficacy of the H1N1 pandemic vaccine in protecting against live virus challenge was also seen to be equivalent to that of the H5N1 vaccine. The protective efficacy of the H1N1 vaccine was also confirmed using a severe combined immunodeficient (SCID mouse model. It was demonstrated that mouse and guinea pig immune sera elicited following active H1N1 vaccination resulted in 100% protection of SCID mice following passive transfer of immune sera and lethal challenge. The immune responses to a whole virus pandemic H1N1 and a split seasonal H1N1 vaccine were also compared in this study. It was demonstrated that the whole virus vaccine induced a balanced Th-1 and Th-2 response in mice, whereas the split vaccine induced mainly a Th-2 response and only minimal levels of Th-1 responses. These data supported the initiation of clinical studies with the same low doses of whole virus vaccine that had previously been demonstrated to be immunogenic in clinical studies with a whole virus H5N1 vaccine.

  14. Geniposide demonstrates anti-inflammatory and antiviral activity against pandemic A/Jiangsu/1/2009 (H1N1) influenza virus infection in vitro and in vivo.

    Science.gov (United States)

    Zhang, Yunshi; Yao, Jing; Qi, Xian; Liu, Xing; Lu, Xieqin; Feng, Ganzhu

    2017-01-01

    Influenza A viruses (IAVs) have been a great threat to human health for centuries, without effective control. Geniposide, a main iridoid glycoside compound extracted from Gardenia jasminoides Ellis fruit, possesses various biological activities including anti-inflammation and anti-virus. Madin-Darby canine kidney (MDCK) cells were infected with pandemic A/Jiangsu/1/2009 (H1N1) influenza virus in vitro. Cytotoxicity and antiviral activity of geniposide were estimated by MTT assay. The influenza respiratory tract infection murine model was established by intranasal instillation of pandemic A/Jiangsu/1/2009 (H1N1) influenza virus. One day after infection, the mice were administered with geniposide (5, 10 or 20 mg/kg/day) or the neuraminidase inhibitor (NAI) peramivir (30 mg/kg/day). Body weight, survival time, viral titre and lung index of the mice were measured. The sandwich enzyme-linked immunosorbent assay (ELISA) was used to examine levels of inflammatory cytokines. The data showed that geniposide had little cytotoxicity on MDCK cells and protected them from pandemic A/Jiangsu/1/2009 (H1N1) influenza virus-induced cell injury. In the infected mice, geniposide treatment significantly restored the body weights, decreased the mortality, alleviated viral titres and virus-induced lung lesions. Geniposide substantially inhibited the virus-induced alveolar wall changes, alveolar haemorrhage and neutrophil-infiltration in lung tissues. Levels of inflammatory mediators, including tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-4, IL-6 and IL-10 were also markedly altered after treatment with geniposide. Our investigation suggested that geniposide effectively inhibited cell damage mediated by pandemic A/Jiangsu/1/2009 (H1N1) influenza virus and mitigated virus-induced acute inflammation.

  15. A whole virus pandemic influenza H1N1 vaccine is highly immunogenic and protective in active immunization and passive protection mouse models.

    Science.gov (United States)

    Kistner, Otfried; Crowe, Brian A; Wodal, Walter; Kerschbaum, Astrid; Savidis-Dacho, Helga; Sabarth, Nicolas; Falkner, Falko G; Mayerhofer, Ines; Mundt, Wolfgang; Reiter, Manfred; Grillberger, Leopold; Tauer, Christa; Graninger, Michael; Sachslehner, Alois; Schwendinger, Michael; Brühl, Peter; Kreil, Thomas R; Ehrlich, Hartmut J; Barrett, P Noel

    2010-02-23

    The recent emergence and rapid spread of a novel swine-derived H1N1 influenza virus has resulted in the first influenza pandemic of this century. Monovalent vaccines have undergone preclinical and clinical development prior to initiation of mass immunization campaigns. We have carried out a series of immunogenicity and protection studies following active immunization of mice, which indicate that a whole virus, nonadjuvanted vaccine is immunogenic at low doses and protects against live virus challenge. The immunogenicity in this model was comparable to that of a whole virus H5N1 vaccine, which had previously been demonstrated to induce high levels of seroprotection in clinical studies. The efficacy of the H1N1 pandemic vaccine in protecting against live virus challenge was also seen to be equivalent to that of the H5N1 vaccine. The protective efficacy of the H1N1 vaccine was also confirmed using a severe combined immunodeficient (SCID) mouse model. It was demonstrated that mouse and guinea pig immune sera elicited following active H1N1 vaccination resulted in 100% protection of SCID mice following passive transfer of immune sera and lethal challenge. The immune responses to a whole virus pandemic H1N1 and a split seasonal H1N1 vaccine were also compared in this study. It was demonstrated that the whole virus vaccine induced a balanced Th-1 and Th-2 response in mice, whereas the split vaccine induced mainly a Th-2 response and only minimal levels of Th-1 responses. These data supported the initiation of clinical studies with the same low doses of whole virus vaccine that had previously been demonstrated to be immunogenic in clinical studies with a whole virus H5N1 vaccine.

  16. Enhanced activity of Anticarsia gemmatalis Hüb. (Lepidoptera: Noctuidae) nuclear polyhedrosis virus by boric acid in the laboratory

    OpenAIRE

    Morales, Lauro; Moscardi, Flávio; Sosa-Gómez, Daniel R.; Paro, Fábio E.; Soldorio, Ivanilda L.

    1997-01-01

    Boric acid concentrations (0.02,0.03,0.045,0.067 and 0.101 g/100 ml of diet) were evaluated in combination with the Anticarsia gemmatalis Hüb. nuclear polyhedrosis virus (AgNPV) for enhanced virali activity against the insect. Seven days after inoculation, the median lethal concentration (LC50) was 1.52 x 10(5) for the AgNPV alone and 7.95 x 10² for the NPV mixed with 0.045g of boric acid/100 ml of diet. At subsequent evaluation dates (9,11 and 14 days after inoculation) LC50's for NPV+boric ...

  17. Biological activity of cloned mammary tumor virus DNA fragments that bind purified glucocorticoid receptor protein in vitro

    International Nuclear Information System (INIS)

    Yamamoto, K.R.; Payvar, F.; Firestone, G.L.; Maler, B.A.; Wrange, O.; Carlstedt-Duke, J.; Gustafsson, J.A.; Chandler, V.L.; Karolinska Institutet, Stockholm, Sweden)

    1983-01-01

    To test whether high-affinity receptor:DNA interactions can be correlated with receptor effects on promoter function in vivo, we have mapped in greater detail the receptor-binding regions on murine mammary tumor virus DNA, using both nitrocellulose-filter binding and electron microscopy. Recombinant plasmids bearing these receptor-binding domains have been transfected into cultured cells, and the expression of the plasmid sequences has been monitored for hormonal regulation. The results are considered in terms of a speculative proposal that the glucocorticoid receptor may effect changes in promoter activity via specific alteration of chromatin and/or DNA structure. 37 references, 6 figures, 2 tables

  18. Inhibition of Nipah Virus Infectin In Vivo: Targeting an Early Stage of Paramyxovirus Fusion Activation during Viral Entry

    Energy Technology Data Exchange (ETDEWEB)

    M Porotto; B Rockx; C Yokoyama; A Talekar; I DeVito; l Palermo; J Liu; R Cortese; M Lu; et al.

    2011-12-31

    In the paramyxovirus cell entry process, receptor binding triggers conformational changes in the fusion protein (F) leading to viral and cellular membrane fusion. Peptides derived from C-terminal heptad repeat (HRC) regions in F have been shown to inhibit fusion by preventing formation of the fusogenic six-helix bundle. We recently showed that the addition of a cholesterol group to HRC peptides active against Nipah virus targets these peptides to the membrane where fusion occurs, dramatically increasing their antiviral effect. In this work, we report that unlike the untagged HRC peptides, which bind to the postulated extended intermediate state bridging the viral and cell membranes, the cholesterol tagged HRC-derived peptides interact with F before the fusion peptide inserts into the target cell membrane, thus capturing an earlier stage in the F-activation process. Furthermore, we show that cholesterol tagging renders these peptides active in vivo: the cholesterol-tagged peptides cross the blood brain barrier, and effectively prevent and treat in an established animal model what would otherwise be fatal Nipah virus encephalitis. The in vivo efficacy of cholesterol-tagged peptides, and in particular their ability to penetrate the CNS, suggests that they are promising candidates for the prevention or therapy of infection by Nipah and other lethal paramyxoviruses.

  19. Humoral markers of active Epstein-Barr virus infection associate with anti-extractable nuclear antigen autoantibodies and plasma galectin-3 binding protein in systemic lupus erythematosus.

    Science.gov (United States)

    Rasmussen, N S; Nielsen, C T; Houen, G; Jacobsen, S

    2016-12-01

    We investigated if signs of active Epstein-Barr virus and cytomegalovirus infections associate with certain autoantibodies and a marker of type I interferon activity in patients with systemic lupus erythematosus. IgM and IgG plasma levels against Epstein-Barr virus early antigen diffuse and cytomegalovirus pp52 were applied as humoral markers of ongoing/recently active Epstein-Barr virus and cytomegalovirus infections, respectively. Plasma galectin-3 binding protein served as a surrogate marker of type I interferon activity. The measurements were conducted in 57 systemic lupus erythematosus patients and 29 healthy controls using ELISAs. Regression analyses and univariate comparisons were performed for associative evaluation between virus serology, plasma galectin-3 binding protein and autoantibodies, along with other clinical and demographic parameters. Plasma galectin-3 binding protein concentrations were significantly higher in systemic lupus erythematosus patients (P = 0.009) and associated positively with Epstein-Barr virus early antigen diffuse-directed antibodies and the presence of autoantibodies against extractable nuclear antigens in adjusted linear regressions (B = 2.02 and 2.02, P = 0.02 and P = 0.002, respectively). Furthermore, systemic lupus erythematosus patients with anti-extractable nuclear antigens had significantly higher antibody levels against Epstein-Barr virus early antigen diffuse (P = 0.02). Our study supports a link between active Epstein-Barr virus infections, positivity for anti-extractable nuclear antigens and increased plasma galectin-3 binding protein concentrations/type I interferon activity in systemic lupus erythematosus patients. © The Author(s) 2016.

  20. Identification of anti-viral activity of the cardenolides, Na+/K+-ATPase inhibitors, against porcine transmissible gastroenteritis virus.

    Science.gov (United States)

    Yang, Cheng-Wei; Chang, Hsin-Yu; Hsu, Hsing-Yu; Lee, Yue-Zhi; Chang, Hsun-Shuo; Chen, Ih-Sheng; Lee, Shiow-Ju

    2017-10-01

    A series of naturally occurring cardenolides that exhibit potent anti-transmissible gastroenteritis virus (TGEV) activity in swine testicular (ST) cells has been identified. In an immunofluorescence assay, these cardenolides were found to diminish the expressions of TGEV nucleocapsid and spike protein, which was used as an indication for viral replication; block TGEV infection induced apoptosis and cytopathic effects; and impart the same trend of inhibitory activity against Na + /K + -ATPase as for anti-TGEV activity. The viral titer inhibition was found to take place in a dose-dependent manner. Knocking down expression of Na + /K + -ATPase, the cellular receptor of cardenolides, in ST cells was found to significantly impair the susceptibility of ST cells to TGEV infectivity. Thus, we have identified Na + /K + -ATPase as an anti-viral drug target and its antagonists, cardenolides, a novel class of anti- TGEV agents. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Broadly Neutralizing Activity of Zika Virus-Immune Sera Identifies a Single Viral Serotype

    Directory of Open Access Journals (Sweden)

    Kimberly A. Dowd

    2016-08-01

    Full Text Available Recent epidemics of Zika virus (ZIKV have been associated with congenital malformation during pregnancy and Guillain-Barré syndrome. There are two ZIKV lineages (African and Asian that share >95% amino acid identity. Little is known regarding the ability of neutralizing antibodies elicited against one lineage to protect against the other. We investigated the breadth of the neutralizing antibody response following ZIKV infection by measuring the sensitivity of six ZIKV strains to neutralization by ZIKV-confirmed convalescent human serum or plasma samples. Contemporary Asian and early African ZIKV strains were similarly sensitive to neutralization regardless of the cellular source of virus. Furthermore, mouse immune serum generated after infection with African or Asian ZIKV strains was capable of neutralizing homologous and heterologous ZIKV strains equivalently. Because our study only defines a single ZIKV serotype, vaccine candidates eliciting robust neutralizing antibody responses should inhibit infection of both ZIKV lineages, including strains circulating in the Americas.

  2. Anti-herpes virus activities of bioactive fraction and isolated pure constituent of Mallotus peltatus: an ethnomedicine from Andaman Islands.

    Science.gov (United States)

    Bag, Paromita; Chattopadhyay, Debprasad; Mukherjee, Hemanta; Ojha, Durbadal; Mandal, Nilanjan; Sarkar, Mamta Chawla; Chatterjee, Tapan; Das, Gobardhan; Chakraborti, Sekhar

    2012-05-24

    Viral infections, particularly the infections caused by herpes simplex virus (HSV), represent one of the most serious public health concerns globally because of their devastating impact. The aim of this study was to evaluate the antiviral potential of methanolic crude extract of an ethnomedicine Mallotus peltatus, its active fraction and pure compound, against HSV-1 F and HSV-2 G. The cytotoxicity (CC(50), the concentration of 50% cellular toxicity), antiviral effective concentration (EC(50), the concentration required to achieve 50% protection against virus-induced cytopathic effect), plaque reduction and the selectivity index (SI, the ratio of CC(50) and EC(50)) was determined. Results showed that the crude methanolic extract of M. peltatus possessed weak anti-HSV activity. In contrast, the active fraction A and isolated ursolic acid from fraction A exhibited potent antiherpesvirus activity against both HSV-1 (EC(50)= 7.8 and 5.5 μg/ml; SI = 22.3 and 20) and HSV-2 (EC(50)= 8.2 and 5.8 μg/ml, and SI = 21.2 and 18.97). The fraction A and isolated ursolic acid (10 μg/ml) inhibited plaque formation of HSV-1 and HSV-2 at more than 80% levels, with a dose dependent antiviral activity, compared to acyclovir. The time response study revealed that the anti-HSV activity of fraction A and isolated ursolic acid is highest at 2-5 h post-infection. Moreover, the time kinetics study by indirect immunofluorescence assay showed a characteristic pattern of small foci of single fluorescent cells in fraction A- treated virus infected cells at 2 h and 4 h post-infection, suggesting drug inhibited viral dissemination. Further, the PCR study with infected cell cultures treated with fraction A and isolated ursolic acid at various time intervals, failed to show amplification at 48-72 h, like acyclovir treated HSV-infected cells. Moreover, fraction A or isolated ursolic acid showed no interaction in combination with acyclovir. This study revealed that bioactive fraction A and isolated

  3. Anti-herpes virus activities of bioactive fraction and isolated pure constituent of Mallotus peltatus: an ethnomedicine from Andaman Islands

    Directory of Open Access Journals (Sweden)

    Bag Paromita

    2012-05-01

    Full Text Available Abstract Background Viral infections, particularly the infections caused by herpes simplex virus (HSV, represent one of the most serious public health concerns globally because of their devastating impact. The aim of this study was to evaluate the antiviral potential of methanolic crude extract of an ethnomedicine Mallotus peltatus, its active fraction and pure compound, against HSV-1 F and HSV-2 G. Result The cytotoxicity (CC50, the concentration of 50% cellular toxicity, antiviral effective concentration (EC50, the concentration required to achieve 50% protection against virus-induced cytopathic effect, plaque reduction and the selectivity index (SI, the ratio of CC50 and EC50 was determined. Results showed that the crude methanolic extract of M. peltatus possessed weak anti-HSV activity. In contrast, the active fraction A and isolated ursolic acid from fraction A exhibited potent antiherpesvirus activity against both HSV-1 (EC50 = 7.8 and 5.5 μg/ml; SI = 22.3 and 20 and HSV-2 (EC50 = 8.2 and 5.8 μg/ml, and SI = 21.2 and 18.97. The fraction A and isolated ursolic acid (10 μg/ml inhibited plaque formation of HSV-1 and HSV-2 at more than 80% levels, with a dose dependent antiviral activity, compared to acyclovir. The time response study revealed that the anti-HSV activity of fraction A and isolated ursolic acid is highest at 2–5 h post-infection. Moreover, the time kinetics study by indirect immunofluorescence assay showed a characteristic pattern of small foci of single fluorescent cells in fraction A- treated virus infected cells at 2 h and 4 h post-infection, suggesting drug inhibited viral dissemination. Further, the PCR study with infected cell cultures treated with fraction A and isolated ursolic acid at various time intervals, failed to show amplification at 48–72 h, like acyclovir treated HSV-infected cells. Moreover, fraction A or isolated ursolic acid showed no interaction in combination with

  4. Role of RNA structure and RNA binding activity of foot-and-mouth disease virus 3C protein in VPg uridylylation and virus replication

    DEFF Research Database (Denmark)

    Nayak, A.; Goodfellow, I. G.; Woolaway, K. E.

    2006-01-01

    The uridylylation of the VPg peptide primer is the first stage in the replication of picornavirus RNA. This process can be achieved in vitro using purified components, including 3B (VPg) with the RNA dependent RNA polymerase (3D(pol)), the precursor 3CD, and an RNA template containing the cre....../bus. We show that certain RNA sequences within the foot-and-mouth disease virus (FMDV) 5' untranslated region but outside of the cre/bus can enhance VPg uridylylation activity. Furthermore, we have shown that the FMDV X protein alone can substitute for 3CD, albeit less efficiently. In addition, the VPg...... precursors, 3B(3)3C and 3B(123)3C, can function as substrates for uridylylation in the absence of added 3C or 3CD. Residues within the FMDV 3C protein involved in interaction with the cre/bus RNA have been identified and are located on the face of the protein opposite from the catalytic site. These residues...

  5. Massive hemoptysis in an immunocompromised pregnant woman with human immunodeficiency virus disease and active pulmonary tuberculosis.

    Science.gov (United States)

    Blyth, David F; Soni, Mahomed A; Moran, Neil F

    2007-12-01

    Massive hemoptysis during pregnancy has been infrequently reported. The management of massive hemoptysis in an immunocompromised 22-year-old woman positive for human immunodeficiency virus undergoing treatment for cavitating pulmonary tuberculosis in the last trimester of pregnancy is reported. The difficulties encountered in applying our standard protocol for massive hemoptysis in this instance are described. The patient was managed by emergency cesarean section and lobectomy.

  6. Population Pharmacokinetics of Tenofovir in Human Immunodeficiency Virus-Infected Patients Taking Highly Active Antiretroviral Therapy

    OpenAIRE

    Jullien, Vincent; Tréluyer, Jean-Marc; Rey, Elisabeth; Jaffray, Patrick; Krivine, Anne; Moachon, Laurence; Lillo-Le Louet, Agnès; Lescoat, Anne; Dupin, Nicolas; Salmon, Dominique; Pons, Gérard; Urien, Saïk

    2005-01-01

    The influence of renal function on tenofovir pharmacokinetics was investigated in 193 human immunodeficiency virus (HIV)-infected patients by the use of a population approach performed with the nonlinear mixed effects modeling program NONMEM. Tenofovir pharmacokinetics was well described by a two-compartment open model in which the absorption and the distribution rate constants are equal. Typical population estimates of apparent central distribution volume (Vc/F), peripheral distribution volu...

  7. Sustained Protein Kinase D Activation Mediates Respiratory Syncytial Virus-Induced Airway Barrier Disruption

    OpenAIRE

    Rezaee, Fariba; DeSando, Samantha A.; Ivanov, Andrei I.; Chapman, Timothy J.; Knowlden, Sara A.; Beck, Lisa A.; Georas, Steve N.

    2013-01-01

    Understanding the regulation of airway epithelial barrier function is a new frontier in asthma and respiratory viral infections. Despite recent progress, little is known about how respiratory syncytial virus (RSV) acts at mucosal sites, and very little is known about its ability to influence airway epithelial barrier function. Here, we studied the effect of RSV infection on the airway epithelial barrier using model epithelia. 16HBE14o- bronchial epithelial cells were grown on Transwell insert...

  8. Discovery and preliminary structure-activity relationship of the marine natural product manzamines as herpes simplex virus type-1 inhibitors.

    Science.gov (United States)

    Palem, Jayavardhana R; Mudit, Mudit; Hsia, Shao-Chung V; Sayed, Khalid A El

    2017-01-01

    Herpes simplex virus type-1 (HSV-1) is a member of alpha-herpesviridae family and is known to cause contagious human infections. The marine habitat is a rich source of structurally unique bioactive secondary metabolites. A small library of marine natural product classes 1-10 has been screened to discover a new hit entity active against HSV-1. Manzamine A showed potent activity against HSV-1 via targeting the viral gene ICP0. Manzamine A is a β-carboline alkaloid isolated from the Indo-Pacific sponge Acanthostrongylophora species. Currently, acyclovir is the drug of choice for HSV-1 infections. Compared with 50 µM acyclovir, manzamine A at 1 µM concentration produced potent repressive effects on viral replication and release of infectious viruses in SIRC cells in recent studies. The potent anti-HSV-1 activity of manzamine A prompted a preliminary structure-activity relationship study by testing targeted manzamines. These included 8-hydroxymanzamine A (11), to test the effect of the C-8 hydroxy substitution at the β-carboline moiety; manzamine E (12), to assess the importance of substitution at the azacyclooctane ring; and ircinal A (13), to determine whether the β-carboline ring is required for the activity. Manzamine A was chemically transformed to its salt forms, manzamine A monohydrochloride (14) and manzamine A monotartrate (15), to test whether improving water solubility and hydrophilicity will positively affect the activity. Compounds were tested for activity against HSV-1 using fluorescent microscopy and plaque assay. The results showed the reduced anti-HSV-1 activity of 11, suggesting that C-8 hydroxy substitution might adversely affect the activity. Similarly, manzamines 12 and 13 showed no activity against HSV-1, indicating the preference of the unsubstituted azacylcooctane and β-carboline rings to the activity. Anti-HSV-1 activity was significantly improved for the manzamine A salts 14 and 15, suggesting that improving the overall water solubility

  9. Discovery of prenylated flavonoids with dual activity against influenza virus and Streptococcus pneumoniae.

    Science.gov (United States)

    Grienke, Ulrike; Richter, Martina; Walther, Elisabeth; Hoffmann, Anja; Kirchmair, Johannes; Makarov, Vadim; Nietzsche, Sandor; Schmidtke, Michaela; Rollinger, Judith M

    2016-06-03

    Influenza virus neuraminidase (NA) is the primary target for influenza therapeutics. Severe complications are often related to secondary pneumonia caused by Streptococcus pneumoniae (pneumococci), which also express NAs. Recently, a NA-mediated lethal synergism between influenza A viruses and pneumococci was described. Therefore, dual inhibitors of both viral and bacterial NAs are expected to be advantageous for the treatment of influenza. We investigated the traditional Chinese herbal drug sāng bái pí (mulberry root bark) as source for anti-infectives. Two prenylated flavonoid derivatives, sanggenon G (4) and sanggenol A (5) inhibited influenza A viral and pneumococcal NAs and, in contrast to the approved NA inhibitor oseltamivir, also planktonic growth and biofilm formation of pneumococci. Evaluation of 27 congeners of 5 revealed a correlation between the degree of prenylation and bioactivity. Abyssinone-V 4'-methyl ether (27) inhibited pneumococcal NA with IC50 = 2.18 μM, pneumococcal growth with MIC = 5.63 μM, and biofilm formation with MBIC = 4.21 μM, without harming lung epithelial cells. Compounds 5 and 27 also disrupt the synergism between influenza A virus and pneumococcal NA in vitro, hence functioning as dual-acting anti-infectives. The results warrant further studies on whether the observed disruption of this synergism is transferable to in vivo systems.

  10. Antiviral activity against human immunodeficiency virus-1 in vitro by myristoylated-peptide from Heliothis virescens

    International Nuclear Information System (INIS)

    Ourth, Donald D.

    2004-01-01

    An insect antiviral compound was purified from Heliothis virescens larval hemolymph by gel-filtration high pressure liquid chromatography (HPLC) and C-18 reverse-phase HPLC and its structure was determined by mass spectrometry. The antiviral compound is an N-myristoylated-peptide containing six amino acids with calculated molecular weight of 916 Da. The N-terminus contains the fatty acid myristoyl, and the C-terminus contains histidine with two methyl groups giving the histidine a permanent positive charge. The remainder of the compound is essentially non-polar. The structure of the compound corresponds with the 'myristate plus basic' motif expressed by certain viral proteins in their binding to the cytoplasmic side of the plasma membrane to initiate viral assembly and budding from a host cell. The insect antiviral compound may inhibit viral assembly and/or budding of viruses from host cells that could include the human immunodeficiency virus-1 (HIV-1) and herpes simplex virus-1 that use this motif for exit from a host cell. Using the formazan assay, the myristoylated-peptide was effective against HIV-1, with a nine times increase in the viability and protection in vitro of treated CEM-SS cells when compared with infected but untreated control cells

  11. Impact of Hepatitis C Virus Coinfection on Response to Highly Active Antiretroviral Therapy and Outcome in HIV-Infected Individuals: A Nationwide Cohort Study

    DEFF Research Database (Denmark)

    Weis, Nina Margrethe; Lindhardt, Bjarne Ø.; Kronborg, Gitte

    2006-01-01

    BACKGROUND: Coinfection with hepatitis C virus (HCV) in human immunodeficiency virus (HIV) type 1-infected patients may decrease the effectiveness of highly active antiretroviral therapy. We determined the impact of HCV infection on response to highly active antiretroviral therapy and outcome among...... Danish patients with HIV-1 infection. METHODS: This prospective cohort study included all adult Danish HIV-1-infected patients who started highly active antiretroviral therapy from 1 January 1995 to 1 January 2004. Patients were classified as HCV positive (positive HCV serological test and/or HCV PCR...... results [443 patients [16%

  12. Impact of hepatitis C virus coinfection on response to highly active antiretroviral therapy and outcome in HIV-infected individuals: a nationwide cohort study

    DEFF Research Database (Denmark)

    Weis, Nina Margrethe; Lindhardt, Bjarne Ø.; Kronborg, Gitte

    2006-01-01

    BACKGROUND: Coinfection with hepatitis C virus (HCV) in human immunodeficiency virus (HIV) type 1-infected patients may decrease the effectiveness of highly active antiretroviral therapy. We determined the impact of HCV infection on response to highly active antiretroviral therapy and outcome among...... Danish patients with HIV-1 infection. METHODS: This prospective cohort study included all adult Danish HIV-1-infected patients who started highly active antiretroviral therapy from 1 January 1995 to 1 January 2004. Patients were classified as HCV positive (positive HCV serological test and/or HCV PCR...... results [443 patients [16%

  13. Double-stranded RNA-induced activation of activating protein-1 promoter is differentially regulated by the non-structural protein 1 of avian influenza A viruses.

    Science.gov (United States)

    Munir, Muhammad; Zohari, Siamak; Belák, Sándor; Berg, Mikael

    2012-02-01

    Non-structural protein 1 (NS1) of influenza A viruses is a multifunctional protein that antagonizes the host immune response by interfering with several host signaling pathways. Based on putative amino acid sequences, NS1 proteins are categorized into two gene pools, allele A and allele B. Here we identified that allele A NS1 proteins of H6N8 and H4N6 are able to inhibit double-stranded RNA (dsRNA)-induced activating protein-1 (AP-1) promoter in cultured cell lines (human A549 and mink lung cells). Allele B NS1 proteins from corresponding subtypes of influenza A viruses are weak in this inhibition, despite significant levels of expression of each NS1 protein in human A549 cells. Furthermore, the capability to inhibit AP-1 promoter was mapped in the effector domain, since RNA binding domain alone lost its ability to inhibit this promoter activation. Chimeric forms of NS1 protein, composed of either RNA binding domain of allele A or B and effector domain of allele A or B, showed comparable inhibition to that of their wild-type NS1 proteins, or to the effector domain of corresponding NS1 proteins. Both alleles A and B NS1 proteins of H6N8 and H4N6 were expressed to significant levels, and were localized predominantly in the nucleus of human A549 cells. These results underscore the importance of the effector domain in inhibiting AP-1 promoter activation, and the biological function of the effector domain in stabilizing the RNA binding domain. Further, we revealed the versatile nature of NS1 in inhibiting the AP-1 transcription factor, in a manner dependent on allele type. Comprehensive studies, focusing on the molecular mechanisms behind this differential inhibition, may facilitate exploration of the zoonotic and pathogenic potential of influenza A viruses.

  14. The Hepatitis B Virus (HBV) HBx Protein Activates AKT To Simultaneously Regulate HBV Replication and Hepatocyte Survival

    Science.gov (United States)

    Rawat, Siddhartha

    2014-01-01

    ABSTRACT Chronic infection with hepatitis B virus (HBV) is a risk factor for developing liver diseases such as hepatocellular carcinoma (HCC). HBx is a multifunctional protein encoded by the HBV genome; HBx stimulates HBV replication and is thought to play an important role in the development of HBV-associated HCC. HBx can activate the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway in some cell lines; however, whether HBx regulates PI3K/AKT signaling in normal hepatocytes has not been evaluated. In studies described here, we assessed HBx activation of PI3K/AKT signaling in an ex vivo model of cultured primary hepatocytes and determined how this HBx activity affects HBV replication. We report that HBx activates AKT in primary hepatocytes and that the activation of AKT decreases HBV replication and HBV mRNA and core protein levels. We show that the transcription factor hepatocyte nuclear factor 4α (HNF4α) is a target of HBx-regulated AKT, and we link HNF4α to HBx-regulated AKT modulation of HBV transcription and replication. Although we and others have shown that HBx stimulates and is likely required for HBV replication, we now report that HBx also activates signals that can diminish the overall level of HBV replication. While this may seem counterintuitive, we show that an important effect of HBx activation of AKT is inhibition of apoptosis. Consequently, our studies suggest that HBx balances HBV replication and cell survival by stimulating signaling pathways that enhance hepatocyte survival at the expense of higher levels of HBV replication. IMPORTANCE Chronic hepatitis B virus (HBV) infection is a common cause of the development of liver cancer. Regulation of cell signaling pathways by the HBV HBx protein is thought to influence the development of HBV-associated liver cancer. HBx stimulates, and may be essential for, HBV replication. We show that HBx activates AKT in hepatocytes to reduce HBV replication. While this seems contradictory to an

  15. Gamma-irradiated influenza A virus provides adjuvant activity to a co-administered poorly immunogenic SFV vaccine in mice.

    Directory of Open Access Journals (Sweden)

    Rachelle eBabb

    2014-06-01

    Full Text Available Many currently available inactivated vaccines require 'adjuvants' to maximise the protective immune responses generated against the antigens of interest. Recent studies in mice with gamma-irradiated influenza A virus (γ-FLU have shown its superior efficacy compared to other forms of inactivated FLU vaccines and its ability to induce both potent type-I interferon (IFN-I responses and the IFN-I associated partial lymphocyte activation. Commonly, IFN-I responses induced by adjuvants, combined in vaccine preparations, have been shown to effectively enhance the immunogenicity of the antigens of interest. Therefore, we investigated the potential adjuvant activity of γ-FLU and the possible effect on antibody responses against co-administrated antigens, using gamma-irradiated Semliki Forest Virus (γ-SFV as the experimental vaccine in mice. Our data show that co-vaccination with γ-FLU and γ-SFV resulted in enhanced SFV-specific antibody responses in terms of increased titres by 6 fold and greater neutralisation efficacy, when compared to vaccination with γ-SFV alone. This study provides promising evidence related to the possible use of γ-FLU as an adjuvant to poorly immunogenic vaccines without compromising the vaccine efficacy of γ-FLU.

  16. Prolonged control of replication-competent dual- tropic human immunodeficiency virus-1 following cessation of highly active antiretroviral therapy

    Directory of Open Access Journals (Sweden)

    Salgado Maria

    2011-12-01

    Full Text Available Abstract Background While initiation of highly active antiretroviral therapy (HAART during primary HIV-1 infection occasionally results in transient control of viral replication after treatment interruption, the vast majority of patients eventually experience a rebound in plasma viremia. Results Here we report a case of a patient who was started on HAART during symptomatic primary infection and who has subsequently maintained viral loads of + T cells. In addition, he does not have any known protective HLA alleles. Thus it is unlikely that he was destined to become a natural elite controller or suppressor. The mechanism of control of viral replication is unclear; he is infected with a CCR5/CXCR4 dual-tropic virus that is fully replication-competent in vitro. In addition, his spouse, who transmitted the virus to him, developed AIDS. The patient's CD4+ T cells are fully susceptible to HIV-1 infection, and he has low titers of neutralizing antibodies to heterologous and autologous HIV-1 isolates. Furthermore, his CD8+ T cells do not have potent HIV suppressive activity. Conclusion This report suggests that some patients may be capable of controlling pathogenic HIV-1 isolates for extended periods of time after the cessation of HAART through a mechanism that is distinct from the potent cytotoxic T lymphocyte (CTL mediated suppression that has been reported in many elite suppressors.

  17. Intracellular route and biological activity of exogenously delivered Rep proteins from the adeno-associated virus type 2

    International Nuclear Information System (INIS)

    Awedikian, Rafi; Francois, Achille; Guilbaud, Mickael; Moullier, Philippe; Salvetti, Anna

    2005-01-01

    The two large Rep proteins, Rep78 and Rep68, from the adeno-associated virus type 2 (AAV-2) are required for AAV-2 DNA replication, site-specific integration, and for the regulation of viral gene expression. The study of their activities is dependent on the ability to deliver these proteins to the cells in a time and dose-dependent manner. We evaluated the ability of a protein transduction domain (PTD) derived from the human immunodeficiency virus 1 (HIV-1) TAT protein to drive the cellular internalization of exogenously delivered PTD-fused Rep68 proteins. This analysis unexpectedly revealed that recombinant Rep68 alone, in the absence of any PTD, could be endocytosed by the cells. Rep68 as the chimeric TAT-Rep68 proteins were internalized through endocytosis in clathrin-coated vesicles and retained in late endosomes/lysosomes with no detectable nuclear localization. In the presence of adenovirus, the Rep proteins could translocate into the nucleus where they displayed a biological activity. These findings support recent reports on the mechan