Liposome-antigen-nucleic acid complexes protect mice from lethal challenge with western and eastern equine encephalitis viruses.

Science.gov (United States)

Phillips, Aaron T; Schountz, Tony; Toth, Ann M; Rico, Amber B; Jarvis, Donald L; Powers, Ann M; Olson, Ken E

2014-02-01

Alphaviruses are mosquito-borne viruses that cause significant disease in animals and humans. Western equine encephalitis virus (WEEV) and eastern equine encephalitis virus (EEEV), two New World alphaviruses, can cause fatal encephalitis, and EEEV is a select agent of concern in biodefense. However, we have no antiviral therapies against alphaviral disease, and current vaccine strategies target only a single alphavirus species. In an effort to develop new tools for a broader response to outbreaks, we designed and tested a novel alphavirus vaccine comprised of cationic lipid nucleic acid complexes (CLNCs) and the ectodomain of WEEV E1 protein (E1ecto). Interestingly, we found that the CLNC component, alone, had therapeutic efficacy, as it increased survival of CD-1 mice following lethal WEEV infection. Immunization with the CLNC-WEEV E1ecto mixture (lipid-antigen-nucleic acid complexes [LANACs]) using a prime-boost regimen provided 100% protection in mice challenged with WEEV subcutaneously, intranasally, or via mosquito. Mice immunized with LANACs mounted a strong humoral immune response but did not produce neutralizing antibodies. Passive transfer of serum from LANAC E1ecto-immunized mice to nonimmune CD-1 mice conferred protection against WEEV challenge, indicating that antibody is sufficient for protection. In addition, the LANAC E1ecto immunization protocol significantly increased survival of mice following intranasal or subcutaneous challenge with EEEV. In summary, our LANAC formulation has therapeutic potential and is an effective vaccine strategy that offers protection against two distinct species of alphavirus irrespective of the route of infection. We discuss plausible mechanisms as well the potential utility of our LANAC formulation as a pan-alphavirus vaccine.

Papaya Lethal Yellowing Virus (PLYV) Infects Vasconcellea cauliflora

NARCIS (Netherlands)

Amaral, P.P.R.; Resende, de R.O.; Souza, M.T.

2006-01-01

Papaya lethal yellowing virus (PLYV) é um dos três vírus descritos infectando mamoeiros (Carica papaya L.) no Brasil. Vasconcellea cauliflora (Jacq.) A. DC., antes denominada de Carica cauliflora (Jacq.), é uma reconhecida fonte de resistência natural ao Papaya ringspot virus (PRSV), causador da

Mutagenesis-mediated virus extinction: virus-dependent effect of viral load on sensitivity to lethal defection.

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Héctor Moreno

Full Text Available BACKGROUND: Lethal mutagenesis is a transition towards virus extinction mediated by enhanced mutation rates during viral genome replication, and it is currently under investigation as a potential new antiviral strategy. Viral load and virus fitness are known to influence virus extinction. Here we examine the effect or the multiplicity of infection (MOI on progeny production of several RNA viruses under enhanced mutagenesis. RESULTS: The effect of the mutagenic base analogue 5-fluorouracil (FU on the replication of the arenavirus lymphocytic choriomeningitis virus (LCMV can result either in inhibition of progeny production and virus extinction in infections carried out at low multiplicity of infection (MOI, or in a moderate titer decrease without extinction at high MOI. The effect of the MOI is similar for LCMV and vesicular stomatitis virus (VSV, but minimal or absent for the picornaviruses foot-and-mouth disease virus (FMDV and encephalomyocarditis virus (EMCV. The increase in mutation frequency and Shannon entropy (mutant spectrum complexity as a result of virus passage in the presence of FU was more accentuated at low MOI for LCMV and VSV, and at high MOI for FMDV and EMCV. We present an extension of the lethal defection model that agrees with the experimental results. CONCLUSIONS: (i Low infecting load favoured the extinction of negative strand viruses, LCMV or VSV, with an increase of mutant spectrum complexity. (ii This behaviour is not observed in RNA positive strand viruses, FMDV or EMCV. (iii The accumulation of defector genomes may underlie the MOI-dependent behaviour. (iv LCMV coinfections are allowed but superinfection is strongly restricted in BHK-21 cells. (v The dissimilar effects of the MOI on the efficiency of mutagenic-based extinction of different RNA viruses can have implications for the design of antiviral protocols based on lethal mutagenesis, presently under development.

Differential replication of Foot-and-mouth disease viruses in mice determine lethality.

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Cacciabue, Marco; García-Núñez, María Soledad; Delgado, Fernando; Currá, Anabella; Marrero, Rubén; Molinari, Paula; Rieder, Elizabeth; Carrillo, Elisa; Gismondi, María Inés

2017-09-01

Adult C57BL/6J mice have been used to study Foot-and-mouth disease virus (FMDV) biology. In this work, two variants of an FMDV A/Arg/01 strain exhibiting differential pathogenicity in adult mice were identified and characterized: a non-lethal virus (A01NL) caused mild signs of disease, whereas a lethal virus (A01L) caused death within 24-48h independently of the dose used. Both viruses caused a systemic infection with pathological changes in the exocrine pancreas. Virus A01L reached higher viral loads in plasma and organs of inoculated mice as well as increased replication in an ovine kidney cell line. Complete consensus sequences revealed 6 non-synonymous changes between A01L and A10NL genomes that might be linked to replication differences, as suggested by in silico prediction studies. Our results highlight the biological significance of discrete genomic variations and reinforce the usefulness of this animal model to study viral determinants of lethality. Copyright © 2017 Elsevier Inc. All rights reserved.

An Adjuvanted A(H5N1) Subvirion Vaccine Elicits Virus-Specific Antibody Response and Improves Protection Against Lethal Influenza Viral Challenge in Mouse Model of Protein Energy Malnutrition.

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Jones, Enitra N; Amoah, Samuel; Cao, Weiping; Sambhara, Suryaprakash; Gangappa, Shivaprakash

2017-09-15

Protein energy malnutrition (PEM) increases susceptibility to infectious diseases, including influenza infection, but no studies have addressed the potential influences of PEM on the immunogenicity and protective efficacy of avian influenza A(H5N1) vaccine. We investigated the role of PEM on vaccine-mediated protection after a lethal challenge with recombinant A(H5N1) virus using isocaloric diets providing either adequate protein (AP; 18% protein) or very low protein (VLP; 2% protein) in an established murine model of influenza vaccination. We demonstrated that mice maintained on a VLP diet succumb to lethal challenge at greater rates than mice maintained on an AP diet, despite comparable immunization regimens. Importantly, there was no virus-induced mortality in both VLP and AP groups of mice when either group was immunized with adjuvanted low-dose A(H5N1) subvirion vaccine. Our results suggest that adjuvanted vaccination in populations where PEM is endemic may be one strategy to boost vaccination-promoted immunity and improve outcomes associated with highly pathogenic A(H5N1). Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

An H5N1-based matrix protein 2 ectodomain tetrameric peptide vaccine provides cross-protection against lethal infection with H7N9 influenza virus.

Science.gov (United States)

Leung, Ho-Chuen; Chan, Chris Chung-Sing; Poon, Vincent Kwok-Man; Zhao, Han-Jun; Cheung, Chung-Yan; Ng, Fai; Huang, Jian-Dong; Zheng, Bo-Jian

2015-04-01

In March 2013, a patient infected with a novel avian influenza A H7N9 virus was reported in China. Since then, there have been 458 confirmed infection cases and 177 deaths. The virus contains several human-adapted markers, indicating that H7N9 has pandemic potential. The outbreak of this new influenza virus highlighted the need for the development of universal influenza vaccines. Previously, we demonstrated that a tetrameric peptide vaccine based on the matrix protein 2 ectodomain (M2e) of the H5N1 virus (H5N1-M2e) could protect mice from lethal infection with different clades of H5N1 and 2009 pandemic H1N1 influenza viruses. In this study, we investigated the cross-protection of H5N1-M2e against lethal infection with the new H7N9 virus. Although five amino acid differences existed at positions 13, 14, 18, 20, and 21 between M2e of H5N1 and H7N9, H5N1-M2e vaccination with either Freund's adjuvant or the Sigma adjuvant system (SAS) induced a high level of anti-M2e antibody, which cross-reacted with H7N9-M2e peptide. A mouse-adapted H7N9 strain, A/Anhui/01/2013m, was used for lethal challenge in animal experiments. H5N1-M2e vaccination provided potent cross-protection against lethal challenge of the H7N9 virus. Reduced viral replication and histopathological damage of mouse lungs were also observed in the vaccinated mice. Our results suggest that the tetrameric H5N1-M2e peptide vaccine could protect against different subtypes of influenza virus infections. Therefore, this vaccine may be an ideal candidate for developing a universal vaccine to prevent the reemergence of avian influenza A H7N9 virus and the emergence of potential novel reassortants of influenza virus.

Protection from lethal infection is determined by innate immune responses in a mouse model of Ebola virus infection

International Nuclear Information System (INIS)

Mahanty, Siddhartha; Gupta, Manisha; Paragas, Jason; Bray, Mike; Ahmed, Rafi; Rollin, Pierre E.

2003-01-01

A mouse-adapted strain of Ebola Zaire virus produces a fatal infection when BALB/cj mice are infected intraperitoneally (ip) but subcutaneous (sc) infection with the same virus fails to produce illness and confers long-term protection from lethal ip rechallenge. To identify immune correlates of protection in this model, we compared viral replication and cytokine/chemokine responses to Ebola virus in mice infected ip (10 PFU/mouse), or sc (100 PFU/mouse) and sc 'immune' mice rechallenged ip (10 6 PFU/mouse) at several time points postinfection (pi). Ebola viral antigens were detected in the serum, liver, spleen, and kidneys of ip-infected mice by day 2 pi, increasing up to day 6. Sc-infected mice and immune mice rechallenged ip had no detectable viral antigens until day 6 pi, when low levels of viral antigens were detected in the livers of sc-infected mice only. TNF-α and MCP-1 were detected earlier and at significantly higher levels in the serum and tissues of ip-infected mice than in sc-infected or immune mice challenged ip. In contrast, high levels of IFN-α and IFN-γ were found in tissues within 2 days after challenge in sc-infected and immune mice but not in ip-infected mice. Mice became resistant to ip challenge within 48 h of sc infection, coinciding with the rise in tissue IFN-α levels. In this model of Ebola virus infection, the nonlethal sc route of infection is associated with an attenuated inflammatory response and early production of antiviral cytokines, particularly IFN-α, as compared with lethal ip infection

Genome Replikin Count Predicts Increased Infectivity/Lethality of Viruses

OpenAIRE

Samuel Bogoch; Elenore S. Bogoch

2012-01-01

The genomes of all groups of viruses whose sequences are listed on Pubmed, specimens since 1918, analyzed by a software from Bioradar UK Ltd., contain Replikins which range in concentration from a Replikin Count (number of Replikins per 100 amino acids) of less than 1 to 30 (see accompanying communications for higher Counts in tuberculosis, malaria, and cancer, associated with higher lethality). Counts of less than 4.0 were found in ‘resting’ virus states; Counts greater than 4....

Myxoma virus M130R is a novel virulence factor required for lethal myxomatosis in rabbits.

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Barrett, John W; Werden, Steven J; Wang, Fuan; McKillop, William M; Jimenez, June; Villeneuve, Danielle; McFadden, Grant; Dekaban, Gregory A

2009-09-01

Myxoma virus (MV) is a highly lethal, rabbit-specific poxvirus that induces a disease called myxomatosis in European rabbits. In an effort to understand the function of predicted immunomodulatory genes we have deleted various viral genes from MV and tested the ability of these knockout viruses to induce lethal myxomatosis. MV encodes a unique 15 kD cytoplasmic protein (M130R) that is expressed late (12h post infection) during infection. M130R is a non-essential gene for MV replication in rabbit, monkey or human cell lines. Construction of a targeted gene knockout virus (vMyx130KO) and infection of susceptible rabbits demonstrate that the M130R knockout virus is attenuated and that loss of M130R expression allows the rabbit host immune system to effectively respond to and control the lethal effects of MV. M130R expression is a bona fide poxviral virulence factor necessary for full and lethal development of myxomatosis.

Protection of Mice from Lethal Vaccinia Virus Infection by Vaccinia Virus Protein Subunits with a CpG Adjuvant

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Sarah Reeman

2017-12-01

Full Text Available Smallpox vaccination carries a high risk of adverse events in recipients with a variety of contra-indications for live vaccines. Although alternative non-replicating vaccines have been described in the form of replication-deficient vaccine viruses, DNA vaccines, and subunit vaccines, these are less efficacious than replicating vaccines in animal models. DNA and subunit vaccines in particular have not been shown to give equivalent protection to the traditional replicating smallpox vaccine. We show here that combinations of the orthopoxvirus A27, A33, B5 and L1 proteins give differing levels of protection when administered in different combinations with different adjuvants. In particular, the combination of B5 and A27 proteins adjuvanted with CpG oligodeoxynucleotides (ODN gives a level of protection in mice that is equivalent to the Lister traditional vaccine in a lethal vaccinia virus challenge model.

A recombinant chimeric La Crosse virus expressing the surface glycoproteins of Jamestown Canyon virus is immunogenic and protective against challenge with either parental virus in mice or monkeys.

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Bennett, R S; Gresko, A K; Nelson, J T; Murphy, B R; Whitehead, S S

2012-01-01

La Crosse virus (LACV) and Jamestown Canyon virus (JCV), family Bunyaviridae, are mosquito-borne viruses that are endemic in North America and recognized as etiologic agents of encephalitis in humans. Both viruses belong to the California encephalitis virus serogroup, which causes 70 to 100 cases of encephalitis a year. As a first step in creating live attenuated viral vaccine candidates for this serogroup, we have generated a recombinant LACV expressing the attachment/fusion glycoproteins of JCV. The JCV/LACV chimeric virus contains full-length S and L segments derived from LACV. For the M segment, the open reading frame (ORF) of LACV is replaced with that derived from JCV and is flanked by the untranslated regions of LACV. The resulting chimeric virus retained the same robust growth kinetics in tissue culture as observed for either parent virus, and the virus remains highly infectious and immunogenic in mice. Although both LACV and JCV are highly neurovirulent in 21 day-old mice, with 50% lethal dose (LD₅₀) values of 0.1 and 0.5 log₁₀ PFU, respectively, chimeric JCV/LACV is highly attenuated and does not cause disease even after intracerebral inoculation of 10³ PFU. Parenteral vaccination of mice with 10¹ or 10³ PFU of JCV/LACV protected against lethal challenge with LACV, JCV, and Tahyna virus (TAHV). The chimeric virus was infectious and immunogenic in rhesus monkeys and induced neutralizing antibodies to JCV, LACV, and TAHV. When vaccinated monkeys were challenged with JCV, they were protected against the development of viremia. Generation of highly attenuated yet immunogenic chimeric bunyaviruses could be an efficient general method for development of vaccines effective against these pathogenic viruses.

Role of Natural Killer Cells in Innate Protection against Lethal Ebola Virus Infection

OpenAIRE

Warfield, Kelly L.; Perkins, Jeremy G.; Swenson, Dana L.; Deal, Emily M.; Bosio, Catharine M.; Aman, M. Javad; Yokoyama, Wayne M.; Young, Howard A.; Bavari, Sina

2004-01-01

Ebola virus is a highly lethal human pathogen and is rapidly driving many wild primate populations toward extinction. Several lines of evidence suggest that innate, nonspecific host factors are potentially critical for survival after Ebola virus infection. Here, we show that nonreplicating Ebola virus-like particles (VLPs), containing the glycoprotein (GP) and matrix protein virus protein (VP)40, administered 1–3 d before Ebola virus infection rapidly induced protective immunity. VLP injectio...

Discovery and Development of Therapeutic Drugs against Lethal Human RNA Viruses: a Multidisciplinary Assault.

Science.gov (United States)

1991-07-16

AD-A239 742 AD GRANT NO: DAMD17-89-Z-9021 TITLE: DISCOVERY AND DEVELOPMENT OF THERAPEUTIC DRUGS AGAINST LETHAL HUMAN RNA VIRUSES: A MULTIDISCIPLINARY...62787A871 AB WrJDA317987 11. TITLE (Include Securty Classification) DISCOVERY AND DEVELOPMENT OF THERAPEUTIC DRUGS AGAINST LETHAL HUMAN RNA VIRUSES: A...G. R. Pettit, III, D.-S. Huang, and G. R. Pettit, 23rd Int’l. Horticulture Congress, Italy, 8/27 - 9/1/90. "Bryostatins Define the Role of Protein

Role of natural killer cells in innate protection against lethal ebola virus infection.

Science.gov (United States)

Warfield, Kelly L; Perkins, Jeremy G; Swenson, Dana L; Deal, Emily M; Bosio, Catharine M; Aman, M Javad; Yokoyama, Wayne M; Young, Howard A; Bavari, Sina

2004-07-19

Ebola virus is a highly lethal human pathogen and is rapidly driving many wild primate populations toward extinction. Several lines of evidence suggest that innate, nonspecific host factors are potentially critical for survival after Ebola virus infection. Here, we show that nonreplicating Ebola virus-like particles (VLPs), containing the glycoprotein (GP) and matrix protein virus protein (VP)40, administered 1-3 d before Ebola virus infection rapidly induced protective immunity. VLP injection enhanced the numbers of natural killer (NK) cells in lymphoid tissues. In contrast to live Ebola virus, VLP treatment of NK cells enhanced cytokine secretion and cytolytic activity against NK-sensitive targets. Unlike wild-type mice, treatment of NK-deficient or -depleted mice with VLPs had no protective effect against Ebola virus infection and NK cells treated with VLPs protected against Ebola virus infection when adoptively transferred to naive mice. The mechanism of NK cell-mediated protection clearly depended on perforin, but not interferon-gamma secretion. Particles containing only VP40 were sufficient to induce NK cell responses and provide protection from infection in the absence of the viral GP. These findings revealed a decisive role for NK cells during lethal Ebola virus infection. This work should open new doors for better understanding of Ebola virus pathogenesis and direct the development of immunotherapeutics, which target the innate immune system, for treatment of Ebola virus infection.

Differential replication of foot-and-mouth disease viruses in mice determine lethality

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Adult C57BL/6J mice have been used to study foot-and-mouth disease virus (FMDV) biology. In this work, two variants of an FMDV A/Arg/01 strain exhibiting differential pathogenicity in adult mice were identified and characterized: a non-lethal virus (A01NL) caused mild signs of disease, whereas a let...

A novel DNA vaccine technology conveying protection against a lethal herpes simplex viral challenge in mice.

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Julie L Dutton

Full Text Available While there are a number of licensed veterinary DNA vaccines, to date, none have been licensed for use in humans. Here, we demonstrate that a novel technology designed to enhance the immunogenicity of DNA vaccines protects against lethal herpes simplex virus 2 (HSV-2 challenge in a murine model. Polynucleotides were modified by use of a codon optimization algorithm designed to enhance immune responses, and the addition of an ubiquitin-encoding sequence to target the antigen to the proteasome for processing and to enhance cytotoxic T cell responses. We show that a mixture of these codon-optimized ubiquitinated and non-ubiquitinated constructs encoding the same viral envelope protein, glycoprotein D, induced both B and T cell responses, and could protect against lethal viral challenge and reduce ganglionic latency. The optimized vaccines, subcloned into a vector suitable for use in humans, also provided a high level of protection against the establishment of ganglionic latency, an important correlate of HSV reactivation and candidate endpoint for vaccines to proceed to clinical trials.

Alternaria alternata challenge at the nasal mucosa results in eosinophilic inflammation and increased susceptibility to influenza virus infection.

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Ma, M; Redes, J L; Percopo, C M; Druey, K M; Rosenberg, H F

2018-06-01

Eosinophils in the nasal mucosa are an elemental feature of allergic rhinitis. Our objective was to explore eosinophilic inflammation and its impact on respiratory virus infection at the nasal mucosa. Inflammation in the nasal mucosae of mice was evaluated in response to repetitive stimulation with strict intranasal volumes of a filtrate of Alternaria alternata. Mice were then challenged with influenza virus. Repetitive stimulation with A. alternata resulted in eosinophil recruitment to the nasal passages in association with elevated levels of IL-5, IL-13 and eotaxin-1; eosinophil recruitment was diminished in eotaxin-1 -/- mice, and abolished in Rag1 -/- mice. A. alternata also resulted in elevated levels of nasal wash IgA in both wild-type and eosinophil-deficient ∆dblGATA mice. Interestingly, A. alternata-treated mice responded to an influenza virus infection with profound weight loss and mortality compared to mice that received diluent alone (0% vs 100% survival, ***P < .001); the lethal response was blunted when A. alternata was heat-inactivated. Minimal differences in virus titre were detected, and eosinophils present in the nasal passages at the time of virus inoculation provided no protection against the lethal sequelae. Interestingly, nasal wash fluids from mice treated with A. alternata included more neutrophils and higher levels of pro-inflammatory mediators in response to virus challenge, among these, IL-6, a biomarker for disease severity in human influenza. Repetitive administration of A. alternata resulted in inflammation of the nasal mucosae and unanticipated morbidity and mortality in response to subsequent challenge with influenza virus. Interestingly, and in contrast to findings in the lower airways, eosinophils recruited to the nasal passages provided no protection against lethal infection. As increased susceptibility to influenza virus among individuals with rhinitis has been the subject of several clinical reports, this model may be

Protection against Multiple Subtypes of Influenza Viruses by Virus-Like Particle Vaccines Based on a Hemagglutinin Conserved Epitope

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Shaoheng Chen

2015-01-01

Full Text Available We selected the conserved sequence in the stalk region of influenza virus hemagglutinin (HA trimmer, the long alpha helix (LAH, as the vaccine candidate sequence, and inserted it into the major immunodominant region (MIR of hepatitis B virus core protein (HBc, and, by using the E. coli expression system, we prepared a recombinant protein vaccine LAH-HBc in the form of virus-like particles (VLP. Intranasal immunization of mice with this LAH-HBc VLP plus cholera toxin B subunit with 0.2% of cholera toxin (CTB* adjuvant could effectively elicit humoral and cellular immune responses and protect mice against a lethal challenge of homologous influenza viruses (A/Puerto Rico/8/1934 (PR8 (H1N1. In addition, passage of the immune sera containing specific antibodies to naïve mice rendered them resistant against a lethal homologous challenge. Immunization with LAH-HBc VLP vaccine plus CTB* adjuvant could also fully protect mice against a lethal challenge of the 2009 pandemic H1N1 influenza virus or the avian H9N2 virus and could partially protect mice against a lethal challenge of the avian H5N1 influenza virus. This study demonstrated that the LAH-HBc VLP vaccine based on a conserved sequence of the HA trimmer stalk region is a promising candidate vaccine for developing a universal influenza vaccine against multiple influenza viruses infections.

Mucosal immunity induced by adenovirus-based H5N1 HPAI vaccine confers protection against a lethal H5N2 avian influenza virus challenge

International Nuclear Information System (INIS)

Park, Ki Seok; Lee, Jiyeung; Ahn, So Shin; Byun, Young-Ho; Seong, Baik Lin; Baek, Yun Hee; Song, Min-Suk; Choi, Young Ki; Na, Yun Jeong; Hwang, Inhwan; Sung, Young Chul; Lee, Chang Geun

2009-01-01

Development of effective vaccines against highly pathogenic avian influenza (HPAI) H5N1 viruses is a global public health priority. Considering the difficulty in predicting HPAI H5N1 pandemic strains, one strategy used in their design includes the development of formulations with the capacity of eliciting broad cross-protective immunity against multiple viral antigens. To this end we constructed a replication-defective recombinant adenovirus-based avian influenza virus vaccine (rAdv-AI) expressing the codon-optimized M2eX-HA-hCD40L and the M1-M2 fusion genes from HPAI H5N1 human isolate. Although there were no significant differences in the systemic immune responses observed between the intramuscular prime-intramuscular boost regimen (IM/IM) and the intranasal prime-intramuscular boost regimen (IN/IM), IN/IM induced more potent CD8 + T cell and antibody responses at mucosal sites than the IM/IM vaccination, resulting in more effective protection against lethal H5N2 avian influenza (AI) virus challenge. These findings suggest that the strategies used to induce multi-antigen-targeted mucosal immunity, such as IN/IM delivery of rAdv-AI, may be a promising approach for developing broad protective vaccines that may be more effective against the new HPAI pandemic strains.

A recombinant Hendra virus G glycoprotein-based subunit vaccine protects ferrets from lethal Hendra virus challenge.

Science.gov (United States)

Pallister, Jackie; Middleton, Deborah; Wang, Lin-Fa; Klein, Reuben; Haining, Jessica; Robinson, Rachel; Yamada, Manabu; White, John; Payne, Jean; Feng, Yan-Ru; Chan, Yee-Peng; Broder, Christopher C

2011-08-05

The henipaviruses, Hendra virus (HeV) and Nipah virus (NiV), are two deadly zoonotic viruses for which no vaccines or therapeutics have yet been approved for human or livestock use. In 14 outbreaks since 1994 HeV has been responsible for multiple fatalities in horses and humans, with all known human infections resulting from close contact with infected horses. A vaccine that prevents virus shedding in infected horses could interrupt the chain of transmission to humans and therefore prevent HeV disease in both. Here we characterise HeV infection in a ferret model and show that it closely mirrors the disease seen in humans and horses with induction of systemic vasculitis, including involvement of the pulmonary and central nervous systems. This model of HeV infection in the ferret was used to assess the immunogenicity and protective efficacy of a subunit vaccine based on a recombinant soluble version of the HeV attachment glycoprotein G (HeVsG), adjuvanted with CpG. We report that ferrets vaccinated with a 100 μg, 20 μg or 4 μg dose of HeVsG remained free of clinical signs of HeV infection following a challenge with 5000 TCID₅₀ of HeV. In addition, and of considerable importance, no evidence of virus or viral genome was detected in any tissues or body fluids in any ferret in the 100 and 20 μg groups, while genome was detected in the nasal washes only of one animal in the 4 μg group. Together, our findings indicate that 100 μg or 20 μg doses of HeVsG vaccine can completely prevent a productive HeV infection in the ferret, suggesting that vaccination to prevent the infection and shedding of HeV is possible. Copyright © 2011 Elsevier Ltd. All rights reserved.

Amino Acid Substitutions Improve the Immunogenicity of H7N7HA Protein and Protect Mice against Lethal H7N7 Viral Challenge.

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Subaschandrabose Rajesh Kumar

Full Text Available Avian influenza A H7N7/NL/219/03 virus creates a serious pandemic threat to human health because it can transmit directly from domestic poultry to humans and from human to human. Our previous vaccine study reported that mice when immunized intranasally (i.n with live Bac-HA were protected from lethal H7N7/NL/219/03 challenge, whereas incomplete protection was obtained when administered subcutaneously (s.c due to the fact that H7N7 is a poor inducer of neutralizing antibodies. Interestingly, our recent vaccine studies reported that mice when vaccinated subcutaneously with Bac-HA (H7N9 was protected against both H7N9 (A/Sh2/2013 and H7N7 virus challenge. HA1 region of both H7N7 and H7N9 viruses are differ at 15 amino acid positions. Among those, we selected three amino acid positions (T143, T198 and I211 in HA1 region of H7N7. These amino acids are located within or near the receptor binding site. Following the selection, we substituted the amino acid at these three positions with amino acids found on H7N9HA wild-type. In this study, we evaluate the impact of amino acid substitutions in the H7N7 HA-protein on the immunogenicity. We generated six mutant constructs from wild-type influenza H7N7HA cDNA by site directed mutagenesis, and individually expressed mutant HA protein on the surface of baculovirus (Bac-HAm and compared their protective efficacy of the vaccines with Bac-H7N7HA wild-type (Bac-HA by lethal H7N7 viral challenge in a mouse model. We found that mice immunized subcutaneously with Bac-HAm constructs T143A or T198A-I211V or I211V-T143A serum showed significantly higher hemagglutination inhibition and neutralization titer against H7N7 and H7N9 viruses when compared to Bac-HA vaccinated mice groups. We also observed low level of lung viral titer, negligible weight loss and complete protection against lethal H7N7 viral challenge. Our results indicated that amino acid substitution at position 143 or 211 improve immunogenicity of H7N7HA

Theories of Lethal Mutagenesis: From Error Catastrophe to Lethal Defection.

Science.gov (United States)

Tejero, Héctor; Montero, Francisco; Nuño, Juan Carlos

2016-01-01

RNA viruses get extinct in a process called lethal mutagenesis when subjected to an increase in their mutation rate, for instance, by the action of mutagenic drugs. Several approaches have been proposed to understand this phenomenon. The extinction of RNA viruses by increased mutational pressure was inspired by the concept of the error threshold. The now classic quasispecies model predicts the existence of a limit to the mutation rate beyond which the genetic information of the wild type could not be efficiently transmitted to the next generation. This limit was called the error threshold, and for mutation rates larger than this threshold, the quasispecies was said to enter into error catastrophe. This transition has been assumed to foster the extinction of the whole population. Alternative explanations of lethal mutagenesis have been proposed recently. In the first place, a distinction is made between the error threshold and the extinction threshold, the mutation rate beyond which a population gets extinct. Extinction is explained from the effect the mutation rate has, throughout the mutational load, on the reproductive ability of the whole population. Secondly, lethal defection takes also into account the effect of interactions within mutant spectra, which have been shown to be determinant for the understanding the extinction of RNA virus due to an augmented mutational pressure. Nonetheless, some relevant issues concerning lethal mutagenesis are not completely understood yet, as so survival of the flattest, i.e. the development of resistance to lethal mutagenesis by evolving towards mutationally more robust regions of sequence space, or sublethal mutagenesis, i.e., the increase of the mutation rate below the extinction threshold which may boost the adaptability of RNA virus, increasing their ability to develop resistance to drugs (including mutagens). A better design of antiviral therapies will still require an improvement of our knowledge about lethal

Chimeric human parainfluenza virus bearing the Ebola virus glycoprotein as the sole surface protein is immunogenic and highly protective against Ebola virus challenge

International Nuclear Information System (INIS)

Bukreyev, Alexander; Marzi, Andrea; Feldmann, Friederike; Zhang Liqun; Yang Lijuan; Ward, Jerrold M.; Dorward, David W.; Pickles, Raymond J.; Murphy, Brian R.; Feldmann, Heinz; Collins, Peter L.

2009-01-01

We generated a new live-attenuated vaccine against Ebola virus (EBOV) based on a chimeric virus HPIV3/ΔF-HN/EboGP that contains the EBOV glycoprotein (GP) as the sole transmembrane envelope protein combined with the internal proteins of human parainfluenza virus type 3 (HPIV3). Electron microscopy analysis of the virus particles showed that they have an envelope and surface spikes resembling those of EBOV and a particle size and shape resembling those of HPIV3. When HPIV3/ΔF-HN/EboGP was inoculated via apical surface of an in vitro model of human ciliated airway epithelium, the virus was released from the apical surface; when applied to basolateral surface, the virus infected basolateral cells but did not spread through the tissue. Following intranasal (IN) inoculation of guinea pigs, scattered infected cells were detected in the lungs by immunohistochemistry, but infectious HPIV3/ΔF-HN/EboGP could not be recovered from the lungs, blood, or other tissues. Despite the attenuation, the virus was highly immunogenic, and a single IN dose completely protected the animals against a highly lethal intraperitoneal challenge of guinea pig-adapted EBOV

A novel highly reproducible and lethal nonhuman primate model for orthopox virus infection.

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Marit Kramski

Full Text Available The intentional re-introduction of Variola virus (VARV, the agent of smallpox, into the human population is of great concern due its bio-terroristic potential. Moreover, zoonotic infections with Cowpox (CPXV and Monkeypox virus (MPXV cause severe diseases in humans. Smallpox vaccines presently available can have severe adverse effects that are no longer acceptable. The efficacy and safety of new vaccines and antiviral drugs for use in humans can only be demonstrated in animal models. The existing nonhuman primate models, using VARV and MPXV, need very high viral doses that have to be applied intravenously or intratracheally to induce a lethal infection in macaques. To overcome these drawbacks, the infectivity and pathogenicity of a particular CPXV was evaluated in the common marmoset (Callithrix jacchus.A CPXV named calpox virus was isolated from a lethal orthopox virus (OPV outbreak in New World monkeys. We demonstrated that marmosets infected with calpox virus, not only via the intravenous but also the intranasal route, reproducibly develop symptoms resembling smallpox in humans. Infected animals died within 1-3 days after onset of symptoms, even when very low infectious viral doses of 5x10(2 pfu were applied intranasally. Infectious virus was demonstrated in blood, saliva and all organs analyzed.We present the first characterization of a new OPV infection model inducing a disease in common marmosets comparable to smallpox in humans. Intranasal virus inoculation mimicking the natural route of smallpox infection led to reproducible infection. In vivo titration resulted in an MID(50 (minimal monkey infectious dose 50% of 8.3x10(2 pfu of calpox virus which is approximately 10,000-fold lower than MPXV and VARV doses applied in the macaque models. Therefore, the calpox virus/marmoset model is a suitable nonhuman primate model for the validation of vaccines and antiviral drugs. Furthermore, this model can help study mechanisms of OPV pathogenesis.

Lethal Zika Virus Disease Models in Young and Older Interferon α/β Receptor Knock Out Mice

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Andrea Marzi

2018-04-01

Full Text Available The common small animal disease models for Zika virus (ZIKV are mice lacking the interferon responses, but infection of interferon receptor α/β knock out (IFNAR−/− mice is not uniformly lethal particularly in older animals. Here we sought to advance this model in regard to lethality for future countermeasure efficacy testing against more recent ZIKV strains from the Asian lineage, preferably the American sublineage. We first infected IFNAR−/− mice subcutaneously with the contemporary ZIKV-Paraiba strain resulting in predominantly neurological disease with ~50% lethality. Infection with ZIKV-Paraiba by different routes established a uniformly lethal model only in young mice (4-week old upon intraperitoneal infection. However, intraperitoneal inoculation of ZIKV-French Polynesia resulted in uniform lethality in older IFNAR−/− mice (10–12-weeks old. In conclusion, we have established uniformly lethal mouse disease models for efficacy testing of antivirals and vaccines against recent ZIKV strains representing the Asian lineage.

A combination in-ovo vaccine for avian influenza virus and Newcastle disease virus.

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Steel, John; Burmakina, Svetlana V; Thomas, Colleen; Spackman, Erica; García-Sastre, Adolfo; Swayne, David E; Palese, Peter

2008-01-24

The protection of poultry from H5N1 highly pathogenic avian influenza A (HPAI) and Newcastle disease virus (NDV) can be achieved through vaccination, as part of a broader disease control strategy. We have previously generated a recombinant influenza virus expressing, (i) an H5 hemagglutinin protein, modified by the removal of the polybasic cleavage peptide and (ii) the ectodomain of the NDV hemagglutinin-neuraminidase (HN) protein in the place of the ectodomain of influenza neuraminidase (Park MS, et al. Proc Natl Acad Sci USA 2006;103(21):8203-8). Here we show this virus is attenuated in primary normal human bronchial epithelial (NHBE) cell culture, and demonstrate protection of C57BL/6 mice from lethal challenge with an H5 HA-containing influenza virus through immunisation with the recombinant virus. In addition, in-ovo vaccination of 18-day-old embryonated chicken eggs provided 90% and 80% protection against highly stringent lethal challenge by NDV and H5N1 virus, respectively. We propose that this virus has potential as a safe in-ovo live, attenuated, bivalent avian influenza and Newcastle disease virus vaccine.

Galantamine is a novel post-exposure therapeutic against lethal VX challenge

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Hilmas, Corey J.; Poole, Melissa J.; Finneran, Kathryn; Clark, Matthew G.; Williams, Patrick T.

2009-01-01

The ability of galantamine hydrobromide (GAL HBr) treatment to antagonize O-ethyl-S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX)-induced lethality, impairment of muscle tension, and electroencephalographic (EEG) changes was assessed in guinea pigs. Guinea pigs were challenged with 16.8 μg/kg VX (2LD50). One min after challenge, animals were administered 0.5 mg/kg atropine sulfate (ATR) and 25 mg/kg pyridine-2-aldoxime methochloride (2-PAM). In addition, guinea pigs were given 0, 1, 2, 4, 8 or 10 mg/kg GAL as a post-exposure treatment immediately prior to ATR and 2-PAM. Animals were either monitored for 24-h survival, scheduled for electroencephalography (EEG) recording, or euthanized 60 min later for measurement of indirectly-elicited muscle tension in the hemidiaphragm. Post-exposure GAL therapy produced a dose-dependent increase in survival from lethal VX challenge. Optimal clinical benefits were observed in the presence of 10 mg/kg GAL, which led to 100% survival of VX-challenged guinea pigs. Based on muscle physiology studies, GAL post-exposure treatment protected the guinea pig diaphragm, the major effector muscle of respiration, from fatigue, tetanic fade, and muscular paralysis. Protection against the paralyzing effects of VX was dose-dependent. In EEG studies, GAL did not alter seizure onset for all doses tested. At the highest dose tested (10 mg/kg), GAL decreased seizure duration when administered as a post-exposure treatment 1 min after VX. GAL also reduced the high correlation associated between seizure activity and lethality after 2LD50 VX challenge. GAL may have additional benefits both centrally and peripherally that are unrelated to its established mechanism as a reversible acetylcholinesterase inhibitor (AChEI).

Lethal Nipah virus infection induces rapid overexpression of CXCL10.

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Cyrille Mathieu

Full Text Available Nipah virus (NiV is a recently emerged zoonotic Paramyxovirus that causes regular outbreaks in East Asia with mortality rate exceeding 75%. Major cellular targets of NiV infection are endothelial cells and neurons. To better understand virus-host interaction, we analyzed the transcriptome profile of NiV infection in primary human umbilical vein endothelial cells. We further assessed some of the obtained results by in vitro and in vivo methods in a hamster model and in brain samples from NiV-infected patients. We found that NiV infection strongly induces genes involved in interferon response in endothelial cells. Among the top ten upregulated genes, we identified the chemokine CXCL10 (interferon-induced protein 10, IP-10, an important chemoattractant involved in the generation of inflammatory immune response and neurotoxicity. In NiV-infected hamsters, which develop pathology similar to what is seen in humans, expression of CXCL10 mRNA was induced in different organs with kinetics that followed NiV replication. Finally, we showed intense staining for CXCL10 in the brain of patients who succumbed to lethal NiV infection during the outbreak in Malaysia, confirming induction of this chemokine in fatal human infections. This study sheds new light on NiV pathogenesis, indicating the role of CXCL10 during the course of infection and suggests that this chemokine may serve as a potential new marker for lethal NiV encephalitis.

Novel Insect-Specific Eilat Virus-Based Chimeric Vaccine Candidates Provide Durable, Mono- and Multivalent, Single-Dose Protection against Lethal Alphavirus Challenge.

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Erasmus, Jesse H; Seymour, Robert L; Kaelber, Jason T; Kim, Dal Y; Leal, Grace; Sherman, Michael B; Frolov, Ilya; Chiu, Wah; Weaver, Scott C; Nasar, Farooq

2018-02-15

Most alphaviruses are mosquito borne and exhibit a broad host range, infecting many different vertebrates, including birds, rodents, equids, humans, and nonhuman primates. Recently, a host-restricted, mosquito-borne alphavirus, Eilat virus (EILV), was described with an inability to infect vertebrate cells based on defective attachment and/or entry, as well as a lack of genomic RNA replication. We investigated the utilization of EILV recombinant technology as a vaccine platform against eastern (EEEV) and Venezuelan equine encephalitis viruses (VEEV), two important pathogens of humans and domesticated animals. EILV chimeras containing structural proteins of EEEV or VEEV were engineered and successfully rescued in Aedes albopictus cells. Cryo-electron microscopy reconstructions at 8 and 11 Å of EILV/VEEV and EILV/EEEV, respectively, showed virion and glycoprotein spike structures similar to those of VEEV-TC83 and other alphaviruses. The chimeras were unable to replicate in vertebrate cell lines or in brains of newborn mice when injected intracranially. Histopathologic examinations of the brain tissues showed no evidence of pathological lesions and were indistinguishable from those of mock-infected animals. A single-dose immunization of either monovalent or multivalent EILV chimera(s) generated neutralizing antibody responses and protected animals against lethal challenge 70 days later. Lastly, a single dose of monovalent EILV chimeras generated protective responses as early as day 1 postvaccination and partial or complete protection by day 6. These data demonstrate the safety, immunogenicity, and efficacy of novel insect-specific EILV-based chimeras as potential EEEV and VEEV vaccines. IMPORTANCE Mostly in the last decade, insect-specific viruses have been discovered in several arbovirus families. However, most of these viruses are not well studied and largely have been ignored. We explored the use of the mosquito-specific alphavirus EILV as an alphavirus vaccine

A rabies vaccine adjuvanted with saponins from leaves of the soap tree (Quillaja brasiliensis) induces specific immune responses and protects against lethal challenge.

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Yendo, Anna Carolina A; de Costa, Fernanda; Cibulski, Samuel P; Teixeira, Thais F; Colling, Luana C; Mastrogiovanni, Mauricio; Soulé, Silvia; Roehe, Paulo M; Gosmann, Grace; Ferreira, Fernando A; Fett-Neto, Arthur G

2016-04-29

Quillaja brasiliensis (Quillajaceae) is a saponin producing species native from southern Brazil and Uruguay. Its saponins are remarkably similar to those of Q. saponaria, which provides most of the saponins used as immunoadjuvants in vaccines. The immunostimulating capacities of aqueous extract (AE) and purified saponin fraction (QB-90) obtained from leaves of Q. brasiliensis were favorably comparable to those of a commercial saponin-based adjuvant preparation (Quil-A) in experimental vaccines against bovine herpesvirus type 1 and 5, poliovirus and bovine viral diarrhea virus in mice model. Herein, the immunogenicity and protection efficacy of rabies vaccines adjuvanted with Q. brasiliensis AE and its saponin fractions were compared with vaccines adjuvanted with either commercial Quil-A or Alum. Mice were vaccinated with one or two doses (on days 0 and 14) of one of the different vaccines and serum levels of total IgG, IgG1 and IgG2a were quantified over time. A challenge experiment with a lethal dose of rabies virus was carried out with the formulations. Viral RNA detection in the brain of mice was performed by qPCR, and RNA copy-numbers were quantified using a standard curve of in vitro transcribed RNA. All Q. brasiliensis saponin-adjuvanted vaccines significantly enhanced levels of specific IgG isotypes when compared with the no adjuvant group (P ≤ 0.05). Overall, one or two doses of saponin-based vaccine were efficient to protect against the lethal rabies exposure. Both AE and saponin fractions from Q. brasiliensis leaves proved potent immunological adjuvants in vaccines against a lethal challenge with a major livestock pathogen, hence confirming their value as competitive or complementary sustainable alternatives to saponins of Q. saponaria. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dengue virus specific IgY provides protection following lethal dengue virus challenge and is neutralizing in the absence of inducing antibody dependent enhancement.

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Fink, Ashley L; Williams, Katherine L; Harris, Eva; Alvine, Travis D; Henderson, Thomas; Schiltz, James; Nilles, Matthew L; Bradley, David S

2017-07-01

Dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) are severe disease manifestations that can occur following sequential infection with different dengue virus serotypes (DENV1-4). At present, there are no licensed therapies to treat DENV-induced disease. DHF and DSS are thought to be mediated by serotype cross-reactive antibodies that facilitate antibody-dependent enhancement (ADE) by binding to viral antigens and then Fcγ receptors (FcγR) on target myeloid cells. Using genetically engineered DENV-specific antibodies, it has been shown that the interaction between the Fc portion of serotype cross-reactive antibodies and FcγR is required to induce ADE. Additionally, it was demonstrated that these antibodies were as neutralizing as their non-modified variants, were incapable of inducing ADE, and were therapeutic following a lethal, antibody-enhanced infection. Therefore, we hypothesized that avian IgY, which do not interact with mammalian FcγR, would provide a novel therapy for DENV-induced disease. We demonstrate here that goose-derived anti-DENV2 IgY neutralized DENV2 and did not induce ADE in vitro. Anti-DENV2 IgY was also protective in vivo when administered 24 hours following a lethal DENV2 infection. We were also able to demonstrate via epitope mapping that both full-length and alternatively spliced anti-DENV2 IgY recognized different epitopes, including epitopes that have not been previously identified. These observations provide evidence for the potential therapeutic applications of goose-derived anti-DENV2 IgY.

Dengue virus specific IgY provides protection following lethal dengue virus challenge and is neutralizing in the absence of inducing antibody dependent enhancement.

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Ashley L Fink

2017-07-01

Full Text Available Dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS are severe disease manifestations that can occur following sequential infection with different dengue virus serotypes (DENV1-4. At present, there are no licensed therapies to treat DENV-induced disease. DHF and DSS are thought to be mediated by serotype cross-reactive antibodies that facilitate antibody-dependent enhancement (ADE by binding to viral antigens and then Fcγ receptors (FcγR on target myeloid cells. Using genetically engineered DENV-specific antibodies, it has been shown that the interaction between the Fc portion of serotype cross-reactive antibodies and FcγR is required to induce ADE. Additionally, it was demonstrated that these antibodies were as neutralizing as their non-modified variants, were incapable of inducing ADE, and were therapeutic following a lethal, antibody-enhanced infection. Therefore, we hypothesized that avian IgY, which do not interact with mammalian FcγR, would provide a novel therapy for DENV-induced disease. We demonstrate here that goose-derived anti-DENV2 IgY neutralized DENV2 and did not induce ADE in vitro. Anti-DENV2 IgY was also protective in vivo when administered 24 hours following a lethal DENV2 infection. We were also able to demonstrate via epitope mapping that both full-length and alternatively spliced anti-DENV2 IgY recognized different epitopes, including epitopes that have not been previously identified. These observations provide evidence for the potential therapeutic applications of goose-derived anti-DENV2 IgY.

Myxoma virus expressing interleukin-15 fails to cause lethal myxomatosis in European rabbits.

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Liu, Jia; Wennier, Sonia; Reinhard, Mary; Roy, Edward; MacNeill, Amy; McFadden, Grant

2009-06-01

Myxoma virus (MYXV) is a poxvirus pathogenic only for European rabbits, but its permissiveness in human cancer cells gives it potential as an oncolytic virus. A recombinant MYXV expressing both the tdTomato red fluorescent protein and interleukin-15 (IL-15) (vMyx-IL-15-tdTr) was constructed. Cells infected with vMyx-IL-15-tdTr secreted bioactive IL-15 and had in vitro replication kinetics similar to that of wild-type MYXV. To determine the safety of this virus for future oncolytic studies, we tested its pathogenesis in European rabbits. In vivo, vMyx-IL-15-tdTr no longer causes lethal myxomatosis. Thus, ectopic IL-15 functions as an antiviral cytokine in vivo, and vMyx-IL-15-tdTr is a safe candidate for animal studies of oncolytic virotherapy.

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

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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.

Post-exposure vaccination with MP-12 lacking NSs protects mice against lethal Rift Valley fever virus challenge.

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Gowen, Brian B; Bailey, Kevin W; Scharton, Dionna; Vest, Zachery; Westover, Jonna B; Skirpstunas, Ramona; Ikegami, Tetsuro

2013-05-01

Rift Valley fever virus (RVFV) causes severe disease in humans and livestock. There are currently no approved antivirals or vaccines for the treatment or prevention of RVF disease in humans. A major virulence factor of RVFV is the NSs protein, which inhibits host transcription including the interferon (IFN)-β gene and promotes the degradation of dsRNA-dependent protein kinase, PKR. We analyzed the efficacy of the live-attenuated MP-12 vaccine strain and MP-12 variants that lack the NSs protein as post-exposure vaccinations. Although parental MP-12 failed to elicit a protective effect in mice challenged with wild-type (wt) RVFV by the intranasal route, significant protection was demonstrated by vaccination with MP-12 strains lacking NSs when they were administered at 20-30 min post-exposure. Viremia and virus replication in liver, spleen and brain were also inhibited by post-exposure vaccination with MP-12 lacking NSs. The protective effect was mostly lost when vaccination was delayed 6 or 24 h after intranasal RVFV challenge. When mice were challenged subcutaneously, efficacy of MP-12 lacking NSs was diminished, most likely due to more rapid dissemination of wt RVFV. Our findings suggest that post-exposure vaccination with MP-12 lacking NSs may be developed as a novel post-exposure treatment to prevent RVF. Copyright © 2013 Elsevier B.V. All rights reserved.

The bureaucratization of war: moral challenges exemplified by the covert lethal drone

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Richard Adams

2013-12-01

Full Text Available This article interrogates the bureaucratization of war, incarnate in the covert lethal drone. Bureaucracies are criticized typically for their complexity, inefficiency, and inflexibility. This article is concerned with their moral indifference. It explores killing, which is so highly administered, so morally remote, and of such scale, that we acknowledge a covert lethal program. This is a bureaucratized program of assassination in contravention of critical human rights. In this article, this program is seen to compromise the advance of global justice. Moreover, the bureaucratization of lethal force is seen to dissolve democratic ideals from within. The bureaucracy isolates the citizens from lethal force applied in their name. People are killed, in the name of the State, but without conspicuous justification, or judicial review, and without informed public debate. This article gives an account of the risk associated with the bureaucratization of the State's lethal power. Exemplified by the covert drone, this is power with formidable reach. It is power as well, which requires great moral sensitivity. Considering the drone program, this article identifies challenges, which will become more prominent and pressing, as technology advances.

Intranasal treatment with a novel immunomodulator mediates innate immune protection against lethal pneumonia virus of mice.

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Martinez, Elisa C; Garg, Ravendra; Shrivastava, Pratima; Gomis, Susantha; van Drunen Littel-van den Hurk, Sylvia

2016-11-01

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections in infants and young children. There are no licensed RSV vaccines available, and the few treatment options for high-risk individuals are either extremely costly or cause severe side effects and toxicity. Immunomodulation mediated by a novel formulation consisting of the toll-like receptor 3 agonist poly(I:C), an innate defense regulator peptide and a polyphosphazene (P-I-P) was evaluated in the context of lethal infection with pneumonia virus of mice (PVM). Intranasal delivery of a single dose of P-I-P protected adult mice against PVM when given 24 h prior to challenge. These animals experienced minimal weight loss, no clinical disease, 100% survival, and reduced lung pathology. Similar clinical outcomes were observed in mice treated up to 3 days prior to infection. P-I-P pre-treatment induced early mRNA and protein expression of key chemokine and cytokine genes, reduced the recruitment of neutrophils and eosinophils, decreased virus titers in the lungs, and modulated the delayed exacerbated nature of PVM disease without any short-term side effects. On day 14 post-infection, P-I-P-treated mice were confirmed to be PVM-free. These results demonstrate the capacity of this formulation to prevent PVM and possibly other viral respiratory infections. Copyright © 2016 Elsevier B.V. All rights reserved.

Myxoma Virus Expressing Interleukin-15 Fails To Cause Lethal Myxomatosis in European Rabbits▿

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Liu, Jia; Wennier, Sonia; Reinhard, Mary; Roy, Edward; MacNeill, Amy; McFadden, Grant

2009-01-01

Myxoma virus (MYXV) is a poxvirus pathogenic only for European rabbits, but its permissiveness in human cancer cells gives it potential as an oncolytic virus. A recombinant MYXV expressing both the tdTomato red fluorescent protein and interleukin-15 (IL-15) (vMyx-IL-15-tdTr) was constructed. Cells infected with vMyx-IL-15-tdTr secreted bioactive IL-15 and had in vitro replication kinetics similar to that of wild-type MYXV. To determine the safety of this virus for future oncolytic studies, we tested its pathogenesis in European rabbits. In vivo, vMyx-IL-15-tdTr no longer causes lethal myxomatosis. Thus, ectopic IL-15 functions as an antiviral cytokine in vivo, and vMyx-IL-15-tdTr is a safe candidate for animal studies of oncolytic virotherapy. PMID:19279088

Inactivated Recombinant Rabies Viruses Displaying Canine Distemper Virus Glycoproteins Induce Protective Immunity against Both Pathogens.

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da Fontoura Budaszewski, Renata; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Yin, Xiangping; Schnell, Matthias J; von Messling, Veronika

2017-04-15

The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Both canine distemper virus (CDV) and rabies virus (RABV) cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wildlife species. In this study, we developed recombinant bivalent vaccine candidates based on recombinant vaccine strain rabies virus particles, which concurrently display the protective CDV and RABV glycoprotein antigens. The recombinant viruses replicated to near-wild-type titers, and the heterologous glycoproteins were efficiently expressed and incorporated in the viral particles. Immunization of ferrets with beta-propiolactone-inactivated recombinant virus particles elicited protective RABV antibody titers, and animals immunized with a combination of CDV attachment protein- and fusion protein-expressing recombinant viruses were protected from lethal CDV challenge. However, animals that were immunized with only a RABV expressing the attachment protein of CDV vaccine strain Onderstepoort succumbed to infection with a more recent wild-type strain, indicating that immune responses to the more conserved fusion protein contribute to protection against heterologous CDV strains. IMPORTANCE Rabies virus and canine distemper virus (CDV) cause high mortality rates and death in many carnivores. While rabies vaccines are inactivated and thus have an excellent safety profile and high stability, live-attenuated CDV vaccines can retain residual virulence in highly susceptible species. Here we generated recombinant inactivated rabies viruses that carry one of the CDV glycoproteins on their surface. Ferrets immunized twice with a mix of recombinant rabies viruses carrying the CDV fusion and attachment glycoproteins were protected from lethal CDV challenge, whereas all animals that received

A cell culture-derived whole virus influenza A vaccine based on magnetic sulfated cellulose particles confers protection in mice against lethal influenza A virus infection.

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Pieler, Michael M; Frentzel, Sarah; Bruder, Dunja; Wolff, Michael W; Reichl, Udo

2016-12-07

Downstream processing and formulation of viral vaccines employs a large number of different unit operations to achieve the desired product qualities. The complexity of individual process steps involved, the need for time consuming studies towards the optimization of virus yields, and very high requirements regarding potency and safety of vaccines results typically in long lead times for the establishment of new processes. To overcome such obstacles, to enable fast screening of potential vaccine candidates, and to explore options for production of low cost veterinary vaccines a new platform for whole virus particle purification and formulation based on magnetic particles has been established. Proof of concept was carried out with influenza A virus particles produced in suspension Madin Darby canine kidney (MDCK) cells. The clarified, inactivated, concentrated, and diafiltered virus particles were bound to magnetic sulfated cellulose particles (MSCP), and directly injected into mice for immunization including positive and negative controls. We show here, that in contrast to the mock-immunized group, vaccination of mice with antigen-loaded MSCP (aMSCP) resulted in high anti-influenza A antibody responses and full protection against a lethal challenge with replication competent influenza A virus. Antiviral protection correlated with a 400-fold reduced number of influenza nucleoprotein gene copies in the lungs of aMSCP immunized mice compared to mock-treated animals, indicating the efficient induction of antiviral immunity by this novel approach. Thus, our data proved the use of MSCP for purification and formulation of the influenza vaccine to be fast and efficient, and to confer protection of mice against influenza A virus infection. Furthermore, the method proposed has the potential for fast purification of virus particles directly from bioreactor harvests with a minimum number of process steps towards formulation of low-cost veterinary vaccines, and for screening

Chimeric Hemagglutinin Constructs Induce Broad Protection against Influenza B Virus Challenge in the Mouse Model.

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Ermler, Megan E; Kirkpatrick, Ericka; Sun, Weina; Hai, Rong; Amanat, Fatima; Chromikova, Veronika; Palese, Peter; Krammer, Florian

2017-06-15

Seasonal influenza virus epidemics represent a significant public health burden. Approximately 25% of all influenza virus infections are caused by type B viruses, and these infections can be severe, especially in children. Current influenza virus vaccines are an effective prophylaxis against infection but are impacted by rapid antigenic drift, which can lead to mismatches between vaccine strains and circulating strains. Here, we describe a broadly protective vaccine candidate based on chimeric hemagglutinins, consisting of globular head domains from exotic influenza A viruses and stalk domains from influenza B viruses. Sequential vaccination with these constructs in mice leads to the induction of broadly reactive antibodies that bind to the conserved stalk domain of influenza B virus hemagglutinin. Vaccinated mice are protected from lethal challenge with diverse influenza B viruses. Results from serum transfer experiments and antibody-dependent cell-mediated cytotoxicity (ADCC) assays indicate that this protection is antibody mediated and based on Fc effector functions. The present data suggest that chimeric hemagglutinin-based vaccination is a viable strategy to broadly protect against influenza B virus infection. IMPORTANCE While current influenza virus vaccines are effective, they are affected by mismatches between vaccine strains and circulating strains. Furthermore, the antiviral drug oseltamivir is less effective for treating influenza B virus infections than for treating influenza A virus infections. A vaccine that induces broad and long-lasting protection against influenza B viruses is therefore urgently needed. Copyright © 2017 American Society for Microbiology.

Rabies Virus Antibodies from Oral Vaccination as a Correlate of Protection against Lethal Infection in Wildlife

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Susan M. Moore

2017-07-01

Full Text Available Both cell-mediated and humoral immune effectors are important in combating rabies infection, although the humoral response receives greater attention regarding rabies prevention. The principle of preventive vaccination has been adopted for strategies of oral rabies vaccination (ORV of wildlife reservoir populations for decades to control circulation of rabies virus in free-ranging hosts. There remains much debate about the levels of rabies antibodies (and the assays to measure them that confer resistance to rabies virus. In this paper, data from published literature and our own unpublished animal studies on the induction of rabies binding and neutralizing antibodies following oral immunization of animals with live attenuated or recombinant rabies vaccines, are examined as correlates of protection against lethal rabies infection in captive challenge settings. Analysis of our studies suggests that, though serum neutralization test results are expected to reflect in vivo protection, the blocking enzyme linked immunosorbent assay (ELISA result at Day 28 was a better predictor of survival. ELISA kits may have an advantage of greater precision and ability to compare results among different studies and laboratories based on the inherent standardization of the kit format. This paper examines current knowledge and study findings to guide meaningful interpretation of serology results in oral baiting monitoring.

Adapted Lethality: What We Can Learn from Guinea Pig-Adapted Ebola Virus Infection Model.

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Cheresiz, S V; Semenova, E A; Chepurnov, A A

2016-01-01

Establishment of small animal models of Ebola virus (EBOV) infection is important both for the study of genetic determinants involved in the complex pathology of EBOV disease and for the preliminary screening of antivirals, production of therapeutic heterologic immunoglobulins, and experimental vaccine development. Since the wild-type EBOV is avirulent in rodents, the adaptation series of passages in these animals are required for the virulence/lethality to emerge in these models. Here, we provide an overview of our several adaptation series in guinea pigs, which resulted in the establishment of guinea pig-adapted EBOV (GPA-EBOV) variants different in their characteristics, while uniformly lethal for the infected animals, and compare the virologic, genetic, pathomorphologic, and immunologic findings with those obtained in the adaptation experiments of the other research groups.

Adapted Lethality: What We Can Learn from Guinea Pig-Adapted Ebola Virus Infection Model

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S. V. Cheresiz

2016-01-01

Full Text Available Establishment of small animal models of Ebola virus (EBOV infection is important both for the study of genetic determinants involved in the complex pathology of EBOV disease and for the preliminary screening of antivirals, production of therapeutic heterologic immunoglobulins, and experimental vaccine development. Since the wild-type EBOV is avirulent in rodents, the adaptation series of passages in these animals are required for the virulence/lethality to emerge in these models. Here, we provide an overview of our several adaptation series in guinea pigs, which resulted in the establishment of guinea pig-adapted EBOV (GPA-EBOV variants different in their characteristics, while uniformly lethal for the infected animals, and compare the virologic, genetic, pathomorphologic, and immunologic findings with those obtained in the adaptation experiments of the other research groups.

A recombinant novirhabdovirus presenting at the surface the E Glycoprotein from West Nile Virus (WNV is immunogenic and provides partial protection against lethal WNV challenge in BALB/c mice.

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Angella Nzonza

Full Text Available West Nile Virus (WNV is a zoonotic mosquito-transmitted flavivirus that can infect and cause disease in mammals including humans. Our study aimed at developing a WNV vectored vaccine based on a fish Novirhabdovirus, the Viral Hemorrhagic Septicemia virus (VHSV. VHSV replicates at temperatures lower than 20°C and is naturally inactivated at higher temperatures. A reverse genetics system has recently been developed in our laboratory for VHSV allowing the addition of genes in the viral genome and the recovery of the respective recombinant viruses (rVHSV. In this study, we have generated rVHSV vectors bearing the complete WNV envelope gene (EWNV (rVHSV-EWNV or fragments encoding E subdomains (either domain III alone or domain III fused to domain II (rVHSV-DIIIWNV and rVHSV-DII-DIIIWNV, respectively in the VHSV genome between the N and P cistrons. With the objective to enhance the targeting of the EWNV protein or EWNV-derived domains to the surface of VHSV virions, Novirhadovirus G-derived signal peptide and transmembrane domain (SPG and TMG were fused to EWNV at its amino and carboxy termini, respectively. By Western-blot analysis, electron microscopy observations or inoculation experiments in mice, we demonstrated that both the EWNV and the DIIIWNV could be expressed at the viral surface of rVHSV upon addition of SPG. Every constructs expressing EWNV fused to SPG protected 40 to 50% of BALB/cJ mice against WNV lethal challenge and specifically rVHSV-SPGEWNV induced a neutralizing antibody response that correlated with protection. Surprisingly, rVHSV expressing EWNV-derived domain III or II and III were unable to protect mice against WNV challenge, although these domains were highly incorporated in the virion and expressed at the viral surface. In this study we demonstrated that a heterologous glycoprotein and non membrane-anchored protein, can be efficiently expressed at the surface of rVHSV making this approach attractive to develop new vaccines

Protection from genital herpes disease, seroconversion and latent infection in a non-lethal murine genital infection model by immunization with an HSV-2 replication-defective mutant virus.

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Diaz, Fernando M; Knipe, David M

2016-01-15

Viral vaccines have traditionally protected against disease, but for viruses that establish latent infection, it is desirable for the vaccine to reduce infection to reduce latent infection and reactivation. While seroconversion has been used in clinical trials of herpes simplex virus (HSV) vaccines to measure protection from infection, this has not been modeled in animal infection systems. To measure the ability of a genital herpes vaccine candidate to protect against various aspects of infection, we established a non-lethal murine model of genital HSV-2 infection, an ELISA assay to measure antibodies specific for infected cell protein 8 (ICP8), and a very sensitive qPCR assay. Using these assays, we observed that immunization with HSV-2 dl5-29 virus reduced disease, viral shedding, seroconversion, and latent infection by the HSV-2 challenge virus. Therefore, it may be feasible to obtain protection against genital disease, seroconversion and latent infection by immunization, even if sterilizing immunity is not achieved. Copyright © 2015 Elsevier Inc. All rights reserved.

Glycoprotein-Specific Antibodies Produced by DNA Vaccination Protect Guinea Pigs from Lethal Argentine and Venezuelan Hemorrhagic Fever

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Golden, Joseph W.; Maes, Piet; Kwilas, Steven A.; Ballantyne, John

2016-01-01

ABSTRACT Several members of the Arenaviridae can cause acute febrile diseases in humans, often resulting in lethality. The use of convalescent-phase human plasma is an effective treatment in humans infected with arenaviruses, particularly species found in South America. Despite this, little work has focused on developing potent and defined immunotherapeutics against arenaviruses. In the present study, we produced arenavirus neutralizing antibodies by DNA vaccination of rabbits with plasmids encoding the full-length glycoprotein precursors of Junín virus (JUNV), Machupo virus (MACV), and Guanarito virus (GTOV). Geometric mean neutralizing antibody titers, as measured by the 50% plaque reduction neutralization test (PRNT50), exceeded 5,000 against homologous viruses. Antisera against each targeted virus exhibited limited cross-species binding and, to a lesser extent, cross-neutralization. Anti-JUNV glycoprotein rabbit antiserum protected Hartley guinea pigs from lethal intraperitoneal infection with JUNV strain Romero when the antiserum was administered 2 days after challenge and provided some protection (∼30%) when administered 4 days after challenge. Treatment starting on day 6 did not protect animals. We further formulated an IgG antibody cocktail by combining anti-JUNV, -MACV, and -GTOV antibodies produced in DNA-vaccinated rabbits. This cocktail protected 100% of guinea pigs against JUNV and GTOV lethal disease. We then expanded on this cocktail approach by simultaneously vaccinating rabbits with a combination of plasmids encoding glycoproteins from JUNV, MACV, GTOV, and Sabia virus (SABV). Sera collected from rabbits vaccinated with the combination vaccine neutralized all four targets. These findings support the concept of using a DNA vaccine approach to generate a potent pan-arenavirus immunotherapeutic. IMPORTANCE Arenaviruses are an important family of emerging viruses. In infected humans, convalescent-phase plasma containing neutralizing antibodies can

Depressed Hypoxic and Hypercapnic Ventilatory Responses at Early Stage of Lethal Avian Influenza A Virus Infection in Mice.

Directory of Open Access Journals (Sweden)

Jianguo Zhuang

Full Text Available H5N1 virus infection results in ~60% mortality in patients primarily due to respiratory failure, but the underlying causes of mortality are unclear. The goal of this study is to reveal respiratory disorders occurring at the early stage of infection that may be responsible for subsequent respiratory failure and death. BALB/c mice were intranasally infected with one of two H5N1 virus strains: HK483 (lethal or HK486 (non-lethal virus. Pulmonary ventilation and the responses to hypoxia (HVR; 7% O2 for 3 min and hypercapnia (HCVR; 7% CO2 for 5 min were measured daily at 2 days prior and 1, 2, and 3 days postinfection (dpi and compared to mortality typically by 8 dpi. At 1, 2, and 3 dpi, immunoreactivities (IR of substance P (SP-IR in the nodose ganglion or tyrosine hydroxylase (TH-IR in the carotid body coupled with the nucleoprotein of influenza A (NP-IR was examined in some mice, while arterial blood was collected in others. Our results showed that at 2 and 3 dpi: 1 both viral infections failed to alter body temperature and weight, [Formula: see text], or induce viremia while producing similarly high lung viral titers; 2 HK483, but not HK486, virus induced tachypnea and depressed HVR and HCVR without changes in arterial blood pH and gases; and 3 only HK483 virus led to NP-IR in vagal SP-IR neurons, but not in the carotid body, and increased density of vagal SP-IR neurons. In addition, all HK483, rather than HK486, mice died at 6 to 8 dpi and the earlier death was correlated with more severe depression of HVR and HCVR. Our data suggest that tachypnea and depressed HVR/HCVR occur at the early stage of lethal H5N1 viral infection associated with viral replication and increased SP-IR density in vagal neurons, which may contribute to the respiratory failure and death.

Infection of mice with a human influenza A/H3N2 virus induces protective immunity against lethal infection with influenza A/H5N1 virus.

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Kreijtz, J H C M; Bodewes, R; van den Brand, J M A; de Mutsert, G; Baas, C; van Amerongen, G; Fouchier, R A M; Osterhaus, A D M E; Rimmelzwaan, G F

2009-08-06

The transmission of highly pathogenic avian influenza (HPAI) A viruses of the H5N1 subtype from poultry to man and the high case fatality rate fuels the fear for a pandemic outbreak caused by these viruses. However, prior infections with seasonal influenza A/H1N1 and A/H3N2 viruses induce heterosubtypic immunity that could afford a certain degree of protection against infection with the HPAI A/H5N1 viruses, which are distantly related to the human influenza A viruses. To assess the protective efficacy of such heterosubtypic immunity mice were infected with human influenza virus A/Hong Kong/2/68 (H3N2) 4 weeks prior to a lethal infection with HPAI virus A/Indonesia/5/05 (H5N1). Prior infection with influenza virus A/Hong Kong/2/68 reduced clinical signs, body weight loss, mortality and virus replication in the lungs as compared to naive mice infected with HPAI virus A/Indonesia/5/05. Priming by infection with respiratory syncytial virus, a non-related virus did not have a beneficial effect on the outcome of A/H5N1 infections, indicating that adaptive immune responses were responsible for the protective effect. In mice primed by infection with influenza A/H3N2 virus cytotoxic T lymphocytes (CTL) specific for NP(366-374) epitope ASNENMDAM and PA(224-232) SCLENFRAYV were observed. A small proportion of these CTL was cross-reactive with the peptide variant derived from the influenza A/H5N1 virus (ASNENMEVM and SSLENFRAYV respectively) and upon challenge infection with the influenza A/H5N1 virus cross-reactive CTL were selectively expanded. These CTL, in addition to those directed to conserved epitopes, shared by the influenza A/H3N2 and A/H5N1 viruses, most likely contributed to accelerated clearance of the influenza A/H5N1 virus infection. Although also other arms of the adaptive immune response may contribute to heterosubtypic immunity, the induction of virus-specific CTL may be an attractive target for development of broad protective vaccines. Furthermore the

USC-087 protects Syrian hamsters against lethal challenge with human species C adenoviruses.

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Toth, Karoly; Spencer, Jacqueline F; Ying, Baoling; Tollefson, Ann E; Hartline, Caroll B; Richard, Eric T; Fan, Jiajun; Lyu, Jinglei; Kashemirov, Boris A; Harteg, Cheryl; Reyna, Dawn; Lipka, Elke; Prichard, Mark N; McKenna, Charles E; Wold, William S M

2018-05-01

Human adenoviruses (AdV) cause generally mild infections of the respiratory and GI tracts as well as some other tissues. However, AdV can cause serious infection in severely immunosuppressed individuals, especially pediatric patients undergoing allogeneic hematopoietic stem cell transplantation, where mortality rates are up to 80% with disseminated disease. Despite the seriousness of AdV disease, there are no drugs approved specifically to treat AdV infections. We report here that USC-087, an N-alkyl tyrosinamide phosphonate ester prodrug of HPMPA, the adenine analog of cidofovir, is highly effective against multiple AdV types in cell culture. USC-087 is also effective against AdV-C6 in our immunosuppressed permissive Syrian hamster model. In this model, hamsters are immunosuppressed by treatment with high dose cyclophosphamide. Injection of AdV-C6 (or AdV-C5) intravenously leads to a disseminated infection that resembles the disease seen in humans, including death. We have tested the efficacy of orally-administered USC-087 against the median lethal dose of intravenously administered AdV-C6. USC-087 completely prevented or significantly decreased mortality when administered up to 4 days post challenge. USC-087 also prevented or significantly decreased liver damage caused by AdV-C6 infection, and suppressed virus replication even when administered 4 days post challenge. These results imply that USC-087 is a promising candidate for drug development against HAdV infections. Copyright © 2018 Elsevier B.V. All rights reserved.

A prophylactic multivalent vaccine against different filovirus species is immunogenic and provides protection from lethal infections with Ebolavirus and Marburgvirus species in non-human primates.

Directory of Open Access Journals (Sweden)

Benoit Callendret

Full Text Available The search for a universal filovirus vaccine that provides protection against multiple filovirus species has been prompted by sporadic but highly lethal outbreaks of Ebolavirus and Marburgvirus infections. A good prophylactic vaccine should be able to provide protection to all known filovirus species and as an upside potentially protect from newly emerging virus strains. We investigated the immunogenicity and protection elicited by multivalent vaccines expressing glycoproteins (GP from Ebola virus (EBOV, Sudan virus (SUDV, Taï Forest virus (TAFV and Marburg virus (MARV. Immune responses against filovirus GP have been associated with protection from disease. The GP antigens were expressed by adenovirus serotypes 26 and 35 (Ad26 and Ad35 and modified Vaccinia virus Ankara (MVA vectors, all selected for their strong immunogenicity and good safety profile. Using fully lethal NHP intramuscular challenge models, we assessed different vaccination regimens for immunogenicity and protection from filovirus disease. Heterologous multivalent Ad26-Ad35 prime-boost vaccination regimens could give full protection against MARV (range 75%-100% protection and EBOV (range 50% to 100% challenge, and partial protection (75% against SUDV challenge. Heterologous multivalent Ad26-MVA prime-boost immunization gave full protection against EBOV challenge in a small cohort study. The use of such multivalent vaccines did not show overt immune interference in comparison with monovalent vaccines. Multivalent vaccines induced GP-specific antibody responses and cellular IFNγ responses to each GP expressed by the vaccine, and cross-reactivity to TAFV GP was detected in a trivalent vaccine expressing GP from EBOV, SUDV and MARV. In the EBOV challenge studies, higher humoral EBOV GP-specific immune responses (p = 0.0004 were associated with survival from EBOV challenge and less so for cellular immune responses (p = 0.0320. These results demonstrate that it is feasible to

A prophylactic multivalent vaccine against different filovirus species is immunogenic and provides protection from lethal infections with Ebolavirus and Marburgvirus species in non-human primates.

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Callendret, Benoit; Vellinga, Jort; Wunderlich, Kerstin; Rodriguez, Ariane; Steigerwald, Robin; Dirmeier, Ulrike; Cheminay, Cedric; Volkmann, Ariane; Brasel, Trevor; Carrion, Ricardo; Giavedoni, Luis D; Patterson, Jean L; Mire, Chad E; Geisbert, Thomas W; Hooper, Jay W; Weijtens, Mo; Hartkoorn-Pasma, Jutta; Custers, Jerome; Grazia Pau, Maria; Schuitemaker, Hanneke; Zahn, Roland

2018-01-01

The search for a universal filovirus vaccine that provides protection against multiple filovirus species has been prompted by sporadic but highly lethal outbreaks of Ebolavirus and Marburgvirus infections. A good prophylactic vaccine should be able to provide protection to all known filovirus species and as an upside potentially protect from newly emerging virus strains. We investigated the immunogenicity and protection elicited by multivalent vaccines expressing glycoproteins (GP) from Ebola virus (EBOV), Sudan virus (SUDV), Taï Forest virus (TAFV) and Marburg virus (MARV). Immune responses against filovirus GP have been associated with protection from disease. The GP antigens were expressed by adenovirus serotypes 26 and 35 (Ad26 and Ad35) and modified Vaccinia virus Ankara (MVA) vectors, all selected for their strong immunogenicity and good safety profile. Using fully lethal NHP intramuscular challenge models, we assessed different vaccination regimens for immunogenicity and protection from filovirus disease. Heterologous multivalent Ad26-Ad35 prime-boost vaccination regimens could give full protection against MARV (range 75%-100% protection) and EBOV (range 50% to 100%) challenge, and partial protection (75%) against SUDV challenge. Heterologous multivalent Ad26-MVA prime-boost immunization gave full protection against EBOV challenge in a small cohort study. The use of such multivalent vaccines did not show overt immune interference in comparison with monovalent vaccines. Multivalent vaccines induced GP-specific antibody responses and cellular IFNγ responses to each GP expressed by the vaccine, and cross-reactivity to TAFV GP was detected in a trivalent vaccine expressing GP from EBOV, SUDV and MARV. In the EBOV challenge studies, higher humoral EBOV GP-specific immune responses (p = 0.0004) were associated with survival from EBOV challenge and less so for cellular immune responses (p = 0.0320). These results demonstrate that it is feasible to generate a

An influenza A virus (H7N9) anti-neuraminidase monoclonal antibody protects mice from morbidity without interfering with the development of protective immunity to subsequent homologous challenge.

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Wilson, Jason R; Belser, Jessica A; DaSilva, Juliana; Guo, Zhu; Sun, Xiangjie; Gansebom, Shane; Bai, Yaohui; Stark, Thomas J; Chang, Jessie; Carney, Paul; Levine, Min Z; Barnes, John; Stevens, James; Maines, Taronna R; Tumpey, Terrence M; York, Ian A

2017-11-01

The emergence of A(H7N9) virus strains with resistance to neuraminidase (NA) inhibitors highlights a critical need to discover new countermeasures for treatment of A(H7N9) virus-infected patients. We previously described an anti-NA mAb (3c10-3) that has prophylactic and therapeutic efficacy in mice lethally challenged with A(H7N9) virus when delivered intraperitoneally (i.p.). Here we show that intrananasal (i.n.) administration of 3c10-3 protects 100% of mice from mortality when treated 24h post-challenge and further characterize the protective efficacy of 3c10-3 using a nonlethal A(H7N9) challenge model. Administration of 3c10-3 i.p. 24h prior to challenge resulted in a significant decrease in viral lung titers and deep sequencing analysis indicated that treatment did not consistently select for viral variants in NA. Furthermore, prophylactic administration of 3c10-3 did not inhibit the development of protective immunity to subsequent homologous virus re-challenge. Taken together, 3c10-3 highlights the potential use of anti-NA mAb to mitigate influenza virus infection. Published by Elsevier Inc.

Prolonged protection against Intranasal challenge with influenza virus following systemic immunization or combinations of mucosal and systemic immunizations with a heat-labile toxin mutant.

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Zhou, Fengmin; Goodsell, Amanda; Uematsu, Yasushi; Vajdy, Michael

2009-04-01

Seasonal influenza virus infections cause considerable morbidity and mortality in the world, and there is a serious threat of a pandemic influenza with the potential to cause millions of deaths. Therefore, practical influenza vaccines and vaccination strategies that can confer protection against intranasal infection with influenza viruses are needed. In this study, we demonstrate that using LTK63, a nontoxic mutant of the heat-labile toxin from Escherichia coli, as an adjuvant for both mucosal and systemic immunizations, systemic (intramuscular) immunization or combinations of mucosal (intranasal) and intramuscular immunizations protected mice against intranasal challenge with a lethal dose of live influenza virus at 3.5 months after the second immunization.

A lethal model of disseminated dengue virus type 1 infection in AG129 mice.

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Milligan, Gregg N; Sarathy, Vanessa V; White, Mellodee M; Greenberg, M Banks; Campbell, Gerald A; Pyles, Richard B; Barrett, Alan D T; Bourne, Nigel

2017-10-01

The mosquito-borne disease dengue is caused by four serologically and genetically related flaviviruses termed DENV-1 to DENV-4. Dengue is a global public health concern, with both the geographical range and burden of disease increasing rapidly. Clinically, dengue ranges from a relatively mild self-limiting illness to a severe life-threatening and sometimes fatal disease. Infection with one DENV serotype produces life-long homotypic immunity, but incomplete and short-term heterotypic protection. The development of small-animal models that recapitulate the characteristics of the disseminated disease seen clinically has been difficult, slowing the development of vaccines and therapeutics. The AG129 mouse (deficient in interferon alpha/beta and gamma receptor signalling) has proven to be valuable for this purpose, with the development of models of disseminated DENV-2,-3 and -4 disease. Recently, a DENV-1 AG129 model was described, but it requires antibody-dependent enhancement (ADE) to produce lethality. Here we describe a new AG129 model utilizing a non-mouse-adapted DENV-1 strain, West Pacific 74, that does not require ADE to induce lethal disease. Following high-titre intraperitoneal challenge, animals experience a virus infection with dissemination to multiple visceral tissues, including the liver, spleen and intestine. The animals also become thrombocytopenic, but vascular leakage is less prominent than in AG129 models with other DENV serotypes. Taken together, our studies demonstrate that this model is an important addition to dengue research, particularly for understanding the pathological basis of the disease between DENV serotypes and allowing the full spectrum of activity to test comparisons for putative vaccines and antivirals.

Modeling Virus Coinfection to Inform Management of Maize Lethal Necrosis in Kenya.

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Hilker, Frank M; Allen, Linda J S; Bokil, Vrushali A; Briggs, Cheryl J; Feng, Zhilan; Garrett, Karen A; Gross, Louis J; Hamelin, Frédéric M; Jeger, Michael J; Manore, Carrie A; Power, Alison G; Redinbaugh, Margaret G; Rúa, Megan A; Cunniffe, Nik J

2017-10-01

Maize lethal necrosis (MLN) has emerged as a serious threat to food security in sub-Saharan Africa. MLN is caused by coinfection with two viruses, Maize chlorotic mottle virus and a potyvirus, often Sugarcane mosaic virus. To better understand the dynamics of MLN and to provide insight into disease management, we modeled the spread of the viruses causing MLN within and between growing seasons. The model allows for transmission via vectors, soil, and seed, as well as exogenous sources of infection. Following model parameterization, we predict how management affects disease prevalence and crop performance over multiple seasons. Resource-rich farmers with large holdings can achieve good control by combining clean seed and insect control. However, crop rotation is often required to effect full control. Resource-poor farmers with smaller holdings must rely on rotation and roguing, and achieve more limited control. For both types of farmer, unless management is synchronized over large areas, exogenous sources of infection can thwart control. As well as providing practical guidance, our modeling framework is potentially informative for other cropping systems in which coinfection has devastating effects. Our work also emphasizes how mathematical modeling can inform management of an emerging disease even when epidemiological information remains scanty. [Formula: see text] Copyright © 2017 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Glycoprotein-Specific Antibodies Produced by DNA Vaccination Protect Guinea Pigs from Lethal Argentine and Venezuelan Hemorrhagic Fever.

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Golden, Joseph W; Maes, Piet; Kwilas, Steven A; Ballantyne, John; Hooper, Jay W

2016-01-20

Several members of the Arenaviridae can cause acute febrile diseases in humans, often resulting in lethality. The use of convalescent-phase human plasma is an effective treatment in humans infected with arenaviruses, particularly species found in South America. Despite this, little work has focused on developing potent and defined immunotherapeutics against arenaviruses. In the present study, we produced arenavirus neutralizing antibodies by DNA vaccination of rabbits with plasmids encoding the full-length glycoprotein precursors of Junín virus (JUNV), Machupo virus (MACV), and Guanarito virus (GTOV). Geometric mean neutralizing antibody titers, as measured by the 50% plaque reduction neutralization test (PRNT(50)), exceeded 5,000 against homologous viruses. Antisera against each targeted virus exhibited limited cross-species binding and, to a lesser extent, cross-neutralization. Anti-JUNV glycoprotein rabbit antiserum protected Hartley guinea pigs from lethal intraperitoneal infection with JUNV strain Romero when the antiserum was administered 2 days after challenge and provided some protection (∼30%) when administered 4 days after challenge. Treatment starting on day 6 did not protect animals. We further formulated an IgG antibody cocktail by combining anti-JUNV, -MACV, and -GTOV antibodies produced in DNA-vaccinated rabbits. This cocktail protected 100% of guinea pigs against JUNV and GTOV lethal disease. We then expanded on this cocktail approach by simultaneously vaccinating rabbits with a combination of plasmids encoding glycoproteins from JUNV, MACV, GTOV, and Sabia virus (SABV). Sera collected from rabbits vaccinated with the combination vaccine neutralized all four targets. These findings support the concept of using a DNA vaccine approach to generate a potent pan-arenavirus immunotherapeutic. Arenaviruses are an important family of emerging viruses. In infected humans, convalescent-phase plasma containing neutralizing antibodies can mitigate the

Profound protection against respiratory challenge with a lethal H7N7 influenza A virus by increasing the magnitude of CD8(+) T-cell memory

DEFF Research Database (Denmark)

Christensen, Jan Pravsgaard; Doherty, P C; Branum, K C

2000-01-01

The recall of CD8(+) T-cell memory established by infecting H-2(b) mice with an H1N1 influenza A virus provided a measure of protection against an extremely virulent H7N7 virus. The numbers of CD8(+) effector and memory T cells specific for the shared, immunodominant D(b)NP(366) epitope were...... greatly increased subsequent to the H7N7 challenge, and though lung titers remained as high as those in naive controls for 5 days or more, the virus was cleared more rapidly. Expanding the CD8(+) memory T-cell pool (10%) by sequential priming with two different influenza A viruses (H3N2-->H1N1......) gave much better protection. Though the H7N7 virus initially grew to equivalent titers in the lungs of naive and double-primed mice, the replicative phase was substantially controlled within 3 days. This tertiary H7N7 challenge caused little increase in the magnitude of the CD8(+) D(b)NP(366)(+) T...

Favipiravir can evoke lethal mutagenesis and extinction of foot-and-mouth disease virus.

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de Avila, Ana Isabel; Moreno, Elena; Perales, Celia; Domingo, Esteban

2017-04-02

Antiviral agents are increasingly considered an option for veterinary medicine. An understanding of their mechanism of activity is important to plan their administration either as monotherapy or in combination with other agents. Previous studies have shown that the broad spectrum antiviral agent favipiravir (T-705) and its derivatives T-1105 and T-1106 are efficient inhibitors of foot-and-mouth disease virus (FMDV) replication in cell culture and in vivo. However, no mechanism for their activity against FMDV has been proposed. In the present study we show that favipiravir (T-705) can act as a lethal mutagen for FMDV in cell culture. Evidence includes virus extinction associated with increase in mutation frequency in the mutant spectrum of 860 residues of the 3D (polymerase)-coding region, and a decrease of specific infectivity while the consensus nucleotide sequence of the region analyzed remained invariant. The mutational spectrum evoked by favipiravir differs from that observed with other viruses in that no predominant transition type is observed, indicating that a movement towards A,U- or G,C-rich regions of sequence space is not a prerequisite for virus extinction. We discuss prospects for the use of favipiravir to assist in the control of FMDV, and its possible broader use in veterinary medicine as an extension of its current status as antiviral agent for human influenza virus. Copyright © 2017 Elsevier B.V. All rights reserved.

Thy1+ NK [corrected] cells from vaccinia virus-primed mice confer protection against vaccinia virus challenge in the absence of adaptive lymphocytes.

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Geoffrey O Gillard

2011-08-01

Full Text Available While immunological memory has long been considered the province of T- and B-lymphocytes, it has recently been reported that innate cell populations are capable of mediating memory responses. We now show that an innate memory immune response is generated in mice following infection with vaccinia virus, a poxvirus for which no cognate germline-encoded receptor has been identified. This immune response results in viral clearance in the absence of classical adaptive T and B lymphocyte populations, and is mediated by a Thy1(+ subset of natural killer (NK cells. We demonstrate that immune protection against infection from a lethal dose of virus can be adoptively transferred with memory hepatic Thy1(+ NK cells that were primed with live virus. Our results also indicate that, like classical immunological memory, stronger innate memory responses form in response to priming with live virus than a highly attenuated vector. These results demonstrate that a defined innate memory cell population alone can provide host protection against a lethal systemic infection through viral clearance.

A Recombinant Adenovirus Expressing Ovine Interferon Tau Prevents Influenza Virus-Induced Lethality in Mice.

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Martín, V; Pascual, E; Avia, M; Rangel, G; de Molina, A; Alejo, A; Sevilla, N

2016-01-06

Ovine interferon tau (IFN-τ) is a unique type I interferon with low toxicity and a broad host range in vivo. We report the generation of a nonreplicative recombinant adenovirus expressing biologically active IFN-τ. Using the B6.A2G-Mx1 mouse model, we showed that single-dose intranasal administration of recombinant Ad5-IFN-τ can effectively prevent lethality and disease induced by highly virulent hv-PR8 influenza virus by activating the interferon response and preventing viral replication. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Potency of whole virus particle and split virion vaccines using dissolving microneedle against challenges of H1N1 and H5N1 influenza viruses in mice.

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Nakatsukasa, Akihiro; Kuruma, Koji; Okamatsu, Masatoshi; Hiono, Takahiro; Suzuki, Mizuho; Matsuno, Keita; Kida, Hiroshi; Oyamada, Takayoshi; Sakoda, Yoshihiro

2017-05-15

Transdermal vaccination using a microneedle (MN) confers enhanced immunity compared with subcutaneous (SC) vaccination. Here we developed a novel dissolving MN patch for the influenza vaccine. The potencies of split virion and whole virus particle (WVP) vaccines prepared from A/Puerto Rico/8/1934 (H1N1) and A/duck/Hokkaido/Vac-3/2007 (H5N1), respectively, were evaluated. MN vaccination induced higher neutralizing antibody responses than SC vaccination in mice. Moreover, MN vaccination with a lower dose of antigens conferred protective immunity against lethal challenges of influenza viruses than SC vaccination in mice. These results suggest that the WVP vaccines administered using MN are an effective combination for influenza vaccine to be further validated in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

African Swine Fever Virus Georgia 2007 with a Deletion of Virulence-Associated Gene 9GL (B119L), when Administered at Low Doses, Leads to Virus Attenuation in Swine and Induces an Effective Protection against Homologous Challenge.

Science.gov (United States)

O'Donnell, Vivian; Holinka, Lauren G; Krug, Peter W; Gladue, Douglas P; Carlson, Jolene; Sanford, Brenton; Alfano, Marialexia; Kramer, Edward; Lu, Zhiqiang; Arzt, Jonathan; Reese, Bo; Carrillo, Consuelo; Risatti, Guillermo R; Borca, Manuel V

2015-08-01

African swine fever virus (ASFV) is the etiological agent of an often lethal disease of domestic pigs. Disease control strategies have been hampered by the unavailability of vaccines against ASFV. Since its introduction in the Republic of Georgia, a highly virulent virus, ASFV Georgia 2007 (ASFV-G), has caused an epizootic that spread rapidly into Eastern European countries. Currently no vaccines are available or under development to control ASFV-G. In the past, genetically modified ASFVs harboring deletions of virulence-associated genes have proven attenuated in swine, inducing protective immunity against challenge with homologous parental viruses. Deletion of the gene 9GL (open reading frame [ORF] B119L) in highly virulent ASFV Malawi-Lil-20/1 produced an attenuated phenotype even when administered to pigs at 10(6) 50% hemadsorption doses (HAD50). Here we report the construction of a genetically modified ASFV-G strain (ASFV-G-Δ9GLv) harboring a deletion of the 9GL (B119L) gene. Like Malawi-Lil-20/1-Δ9GL, ASFV-G-Δ9GL showed limited replication in primary swine macrophages. However, intramuscular inoculation of swine with 10(4) HAD50 of ASFV-G-Δ9GL produced a virulent phenotype that, unlike Malawi-Lil-20/1-Δ9GL, induced a lethal disease in swine like parental ASFV-G. Interestingly, lower doses (10(2) to 10(3) HAD50) of ASFV-G-Δ9GL did not induce a virulent phenotype in swine and when challenged protected pigs against disease. A dose of 10(2) HAD50 of ASFV-G-Δ9GLv conferred partial protection when pigs were challenged at either 21 or 28 days postinfection (dpi). An ASFV-G-Δ9GL HAD50 of 10(3) conferred partial and complete protection at 21 and 28 dpi, respectively. The information provided here adds to our recent report on the first attempts toward experimental vaccines against ASFV-G. The main problem for controlling ASF is the lack of vaccines. Studies on ASFV virulence lead to the production of genetically modified attenuated viruses that induce protection

Lethal influenza virus infection in macaques is associated with early dysregulation of inflammatory related genes.

Directory of Open Access Journals (Sweden)

Cristian Cillóniz

2009-10-01

Full Text Available The enormous toll on human life during the 1918-1919 Spanish influenza pandemic is a constant reminder of the potential lethality of influenza viruses. With the declaration by the World Health Organization of a new H1N1 influenza virus pandemic, and with continued human cases of highly pathogenic H5N1 avian influenza virus infection, a better understanding of the host response to highly pathogenic influenza viruses is essential. To this end, we compared pathology and global gene expression profiles in bronchial tissue from macaques infected with either the reconstructed 1918 pandemic virus or the highly pathogenic avian H5N1 virus A/Vietnam/1203/04. Severe pathology was observed in respiratory tissues from 1918 virus-infected animals as early as 12 hours after infection, and pathology steadily increased at later time points. Although tissues from animals infected with A/Vietnam/1203/04 also showed clear signs of pathology early on, less pathology was observed at later time points, and there was evidence of tissue repair. Global transcriptional profiles revealed that specific groups of genes associated with inflammation and cell death were up-regulated in bronchial tissues from animals infected with the 1918 virus but down-regulated in animals infected with A/Vietnam/1203/04. Importantly, the 1918 virus up-regulated key components of the inflammasome, NLRP3 and IL-1beta, whereas these genes were down-regulated by A/Vietnam/1203/04 early after infection. TUNEL assays revealed that both viruses elicited an apoptotic response in lungs and bronchi, although the response occurred earlier during 1918 virus infection. Our findings suggest that the severity of disease in 1918 virus-infected macaques is a consequence of the early up-regulation of cell death and inflammatory related genes, in which additive or synergistic effects likely dictate the severity of tissue damage.

Immunization of Pigs by DNA Prime and Recombinant Vaccinia Virus Boost To Identify and Rank African Swine Fever Virus Immunogenic and Protective Proteins.

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Jancovich, James K; Chapman, Dave; Hansen, Debra T; Robida, Mark D; Loskutov, Andrey; Craciunescu, Felicia; Borovkov, Alex; Kibler, Karen; Goatley, Lynnette; King, Katherine; Netherton, Christopher L; Taylor, Geraldine; Jacobs, Bertram; Sykes, Kathryn; Dixon, Linda K

2018-04-15

African swine fever virus (ASFV) causes an acute hemorrhagic fever in domestic pigs, with high socioeconomic impact. No vaccine is available, limiting options for control. Although live attenuated ASFV can induce up to 100% protection against lethal challenge, little is known of the antigens which induce this protective response. To identify additional ASFV immunogenic and potentially protective antigens, we cloned 47 viral genes in individual plasmids for gene vaccination and in recombinant vaccinia viruses. These antigens were selected to include proteins with different functions and timing of expression. Pools of up to 22 antigens were delivered by DNA prime and recombinant vaccinia virus boost to groups of pigs. Responses of immune lymphocytes from pigs to individual recombinant proteins and to ASFV were measured by interferon gamma enzyme-linked immunosorbent spot (ELISpot) assays to identify a subset of the antigens that consistently induced the highest responses. All 47 antigens were then delivered to pigs by DNA prime and recombinant vaccinia virus boost, and pigs were challenged with a lethal dose of ASFV isolate Georgia 2007/1. Although pigs developed clinical and pathological signs consistent with acute ASFV, viral genome levels were significantly reduced in blood and several lymph tissues in those pigs immunized with vectors expressing ASFV antigens compared with the levels in control pigs. IMPORTANCE The lack of a vaccine limits the options to control African swine fever. Advances have been made in the development of genetically modified live attenuated ASFV that can induce protection against challenge. However, there may be safety issues relating to the use of these in the field. There is little information about ASFV antigens that can induce a protective immune response against challenge. We carried out a large screen of 30% of ASFV antigens by delivering individual genes in different pools to pigs by DNA immunization prime and recombinant vaccinia

H5N1 whole-virus vaccine induces neutralizing antibodies in humans which are protective in a mouse passive transfer model.

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M Keith Howard

Full Text Available BACKGROUND: Vero cell culture-derived whole-virus H5N1 vaccines have been extensively tested in clinical trials and consistently demonstrated to be safe and immunogenic; however, clinical efficacy is difficult to evaluate in the absence of wide-spread human disease. A lethal mouse model has been utilized which allows investigation of the protective efficacy of active vaccination or passive transfer of vaccine induced sera following lethal H5N1 challenge. METHODS: We used passive transfer of immune sera to investigate antibody-mediated protection elicited by a Vero cell-derived, non-adjuvanted inactivated whole-virus H5N1 vaccine. Mice were injected intravenously with H5N1 vaccine-induced rodent or human immune sera and subsequently challenged with a lethal dose of wild-type H5N1 virus. RESULTS: Passive transfer of H5N1 vaccine-induced mouse, guinea pig and human immune sera provided dose-dependent protection of recipient mice against lethal challenge with wild-type H5N1 virus. Protective dose fifty values for serum H5N1 neutralizing antibody titers were calculated to be ≤1∶11 for all immune sera, independently of source species. CONCLUSIONS: These data underpin the confidence that the Vero cell culture-derived, whole-virus H5N1 vaccine will be effective in a pandemic situation and support the use of neutralizing serum antibody titers as a correlate of protection for H5N1 vaccines.

Gamma-irradiated influenza A virus can prime for a cross-reactive and cross-protective immune response against influenza A viruses

International Nuclear Information System (INIS)

Mullbacher, A.; Ada, G.L.; Tha Hla, R.

1988-01-01

A-strain influenza virus A/JAP (H2N2) was tested for its ability to induce cytotoxic T cells (Tc) after being rendered non-infectious by either UV or gamma irradiation. Gamma-irradiated virus proved to be more efficient than UV-inactivated virus in priming for a memory Tc cell response or in boosting memory spleen cells in vitro. Most importantly, γ-inactivated, but not UV-inactivated, A/JAP immunized animals survived lethal challenge with heterologous (A/PC(H3N2), A/WSN(H1N1)) virus as effectively as mice primed with infectious virus

Protective Monotherapy Against Lethal Ebola Virus Infection by a Potently Neutralizing Antibody

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2016-07-11

were 49   identified and enrolled in VRC200 clinical trial #NCT00067054 after giving signed 50   informed consent . Peripheral blood mononuclear...illness 56   when administered one day after lethal challenge. Treatment with a single human 57   mAb suggests a simplified therapeutic strategy for...efforts to simplify the ZMapp regimen to contain fewer mAbs have not been successful in 75   the macaque EVD model (7). We sought to isolate

Rift valley fever virus lacking the NSs and NSm genes is highly attenuated, confers protective immunity from virulent virus challenge, and allows for differential identification of infected and vaccinated animals.

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Bird, Brian H; Albariño, César G; Hartman, Amy L; Erickson, Bobbie Rae; Ksiazek, Thomas G; Nichol, Stuart T

2008-03-01

Rift Valley fever (RVF) virus is a mosquito-borne human and veterinary pathogen associated with large outbreaks of severe disease throughout Africa and more recently the Arabian peninsula. Infection of livestock can result in sweeping "abortion storms" and high mortality among young animals. Human infection results in self-limiting febrile disease that in approximately 1 to 2% of patients progresses to more serious complications including hepatitis, encephalitis, and retinitis or a hemorrhagic syndrome with high fatality. The virus S segment-encoded NSs and the M segment-encoded NSm proteins are important virulence factors. The development of safe, effective vaccines and tools to screen and evaluate antiviral compounds is critical for future control strategies. Here, we report the successful reverse genetics generation of multiple recombinant enhanced green fluorescent protein-tagged RVF viruses containing either the full-length, complete virus genome or precise deletions of the NSs gene alone or the NSs/NSm genes in combination, thus creating attenuating deletions on multiple virus genome segments. These viruses were highly attenuated, with no detectable viremia or clinical illness observed with high challenge dosages (1.0 x 10(4) PFU) in the rat lethal disease model. A single-dose immunization regimen induced robust anti-RVF virus immunoglobulin G antibodies (titer, approximately 1:6,400) by day 26 postvaccination. All vaccinated animals that were subsequently challenged with a high dose of virulent RVF virus survived infection and could be serologically differentiated from naïve, experimentally infected animals by the lack of NSs antibodies. These rationally designed marker RVF vaccine viruses will be useful tools for in vitro screening of therapeutic compounds and will provide a basis for further development of RVF virus marker vaccines for use in endemic regions or following the natural or intentional introduction of the virus into previously unaffected areas.

Complex adenovirus-vectored vaccine protects guinea pigs from three strains of Marburg virus challenges

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Wang Danher; Hevey, Michael; Juompan, Laure Y.; Trubey, Charles M.; Raja, Nicholas U.; Deitz, Stephen B.; Woraratanadharm, Jan; Luo Min; Yu Hong; Swain, Benjamin M.; Moore, Kevin M.; Dong, John Y.

2006-01-01

The Marburg virus (MARV), an African filovirus closely related to the Ebola virus, causes a deadly hemorrhagic fever in humans, with up to 90% mortality. Currently, treatment of disease is only supportive, and no vaccines are available to prevent spread of MARV infections. In order to address this need, we have developed and characterized a novel recombinant vaccine that utilizes a single complex adenovirus-vectored vaccine (cAdVax) to overexpress a MARV glycoprotein (GP) fusion protein derived from the Musoke and Ci67 strains of MARV. Vaccination with the cAdVaxM(fus) vaccine led to efficient production of MARV-specific antibodies in both mice and guinea pigs. Significantly, guinea pigs vaccinated with at least 5 x 10 7 pfu of cAdVaxM(fus) vaccine were 100% protected against lethal challenges by the Musoke, Ci67 and Ravn strains of MARV, making it a vaccine with trivalent protective efficacy. Therefore, the cAdVaxM(fus) vaccine serves as a promising vaccine candidate to prevent and contain multi-strain infections by MARV

An antivector vaccine protects against a lethal vector-borne pathogen.

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Milan Labuda

2006-04-01

Full Text Available Vaccines that target blood-feeding disease vectors, such as mosquitoes and ticks, have the potential to protect against the many diseases caused by vector-borne pathogens. We tested the ability of an anti-tick vaccine derived from a tick cement protein (64TRP of Rhipicephalus appendiculatus to protect mice against tick-borne encephalitis virus (TBEV transmitted by infected Ixodes ricinus ticks. The vaccine has a "dual action" in immunized animals: when infested with ticks, the inflammatory and immune responses first disrupt the skin feeding site, resulting in impaired blood feeding, and then specific anti-64TRP antibodies cross-react with midgut antigenic epitopes, causing rupture of the tick midgut and death of engorged ticks. Three parameters were measured: "transmission," number of uninfected nymphal ticks that became infected when cofeeding with an infected adult female tick; "support," number of mice supporting virus transmission from the infected tick to cofeeding uninfected nymphs; and "survival," number of mice that survived infection by tick bite and subsequent challenge by intraperitoneal inoculation of a lethal dose of TBEV. We show that one dose of the 64TRP vaccine protects mice against lethal challenge by infected ticks; control animals developed a fatal viral encephalitis. The protective effect of the 64TRP vaccine was comparable to that of a single dose of a commercial TBEV vaccine, while the transmission-blocking effect of 64TRP was better than that of the antiviral vaccine in reducing the number of animals supporting virus transmission. By contrast, the commercial antitick vaccine (TickGARD that targets only the tick's midgut showed transmission-blocking activity but was not protective. The 64TRP vaccine demonstrates the potential to control vector-borne disease by interfering with pathogen transmission, apparently by mediating a local cutaneous inflammatory immune response at the tick-feeding site.

Back to the future: revisiting HIV-1 lethal mutagenesis

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Dapp, Michael J.; Patterson, Steven E.; Mansky, Louis M.

2012-01-01

The concept of eliminating HIV-1 infectivity by elevating the viral mutation rate was first proposed over a decade ago, even though the general concept had been conceived earlier for RNA viruses. Lethal mutagenesis was originally viewed as a novel chemotherapeutic approach for treating HIV-1 infection in which use of a viral mutagen would over multiple rounds of replication lead to the lethal accumulation of mutations, rendering the virus population non infectious – known as the slow mutation accumulation model. There have been limitations in obtaining good efficacy data with drug leads, leaving some doubt into clinical translation. More recent studies of the APOBEC3 proteins as well as new progress in the use of nucleoside analogs for inducing lethal mutagenesis have helped to refocus attention on rapid induction of HIV-1 lethal mutagenesis in a single or limited number of replication cycles leading to a rapid mutation accumulation model. PMID:23195922

An inactivated whole-virus porcine parvovirus vaccine protects pigs against disease but does not prevent virus shedding even after homologous virus challenge.

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Foerster, Tessa; Streck, André Felipe; Speck, Stephanie; Selbitz, Hans-Joachim; Lindner, Thomas; Truyen, Uwe

2016-06-01

Inactivated whole-virus vaccines against porcine parvovirus (PPV) can prevent disease but not infection and virus shedding after heterologous virus challenge. Here, we showed that the same is true for a homologous challenge. Pregnant sows were vaccinated with an experimental inactivated vaccine based on PPV strain 27a. They were challenged on day 40 of gestation with the virulent porcine parvovirus PPV-27a from which the vaccine was prepared (homologous challenge). On day 90 of gestation, the fetuses from vaccinated sows were protected against disease, while the fetuses of the non-vaccinated sows (control group) exhibited signs of parvovirus disease. All gilts, whether vaccinated or not vaccinated, showed a boost of PPV-specific antibodies indicative of virus infection and replication. Low DNA copy numbers, but not infectious virus, could be demonstrated in nasal or rectal swabs of immunized sows, but high copy numbers of challenge virus DNA as well as infectious virus could both be demonstrated in non-vaccinated sows.

Prion protein protects mice from lethal infection with influenza A viruses.

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Junji Chida

2018-05-01

Full Text Available The cellular prion protein, designated PrPC, is a membrane glycoprotein expressed abundantly in brains and to a lesser extent in other tissues. Conformational conversion of PrPC into the amyloidogenic isoform is a key pathogenic event in prion diseases. However, the physiological functions of PrPC remain largely unknown, particularly in non-neuronal tissues. Here, we show that PrPC is expressed in lung epithelial cells, including alveolar type 1 and 2 cells and bronchiolar Clara cells. Compared with wild-type (WT mice, PrPC-null mice (Prnp0/0 were highly susceptible to influenza A viruses (IAVs, with higher mortality. Infected Prnp0/0 lungs were severely injured, with higher inflammation and higher apoptosis of epithelial cells, and contained higher reactive oxygen species (ROS than control WT lungs. Treatment with a ROS scavenger or an inhibitor of xanthine oxidase (XO, a major ROS-generating enzyme in IAV-infected lungs, rescued Prnp0/0 mice from the lethal infection with IAV. Moreover, Prnp0/0 mice transgenic for PrP with a deletion of the Cu-binding octapeptide repeat (OR region, Tg(PrPΔOR/Prnp0/0 mice, were also highly susceptible to IAV infection. These results indicate that PrPC has a protective role against lethal infection with IAVs through the Cu-binding OR region by reducing ROS in infected lungs. Cu content and the activity of anti-oxidant enzyme Cu/Zn-dependent superoxide dismutase, SOD1, were lower in Prnp0/0 and Tg(PrPΔOR/Prnp0/0 lungs than in WT lungs. It is thus conceivable that PrPC functions to maintain Cu content and regulate SOD1 through the OR region in lungs, thereby reducing ROS in IAV-infected lungs and eventually protecting them from lethal infection with IAVs. Our current results highlight the role of PrPC in protection against IAV infection, and suggest that PrPC might be a novel target molecule for anti-influenza therapeutics.

Virus wars: using one virus to block the spread of another

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Matthew L. Paff

2016-06-01

Full Text Available The failure of traditional interventions to block and cure HIV infections has led to novel proposals that involve treating infections with therapeutic viruses–infectious viruses that specifically inhibit HIV propagation in the host. Early efforts in evaluating these proposals have been limited chiefly to mathematical models of dynamics, for lack of suitable empirical systems. Here we propose, develop and analyze an empirical system of a therapeutic virus that protects a host cell population against a lethal virus. The empirical system uses E. coli bacteria as the host cell population, an RNA phage as the lethal virus and a filamentous phage as the therapeutic virus. Basic dynamic properties are established for each virus alone and then together. Observed dynamics broadly agree with those predicted by a computer simulation model, although some differences are noted. Two cases of dynamics are contrasted, differing in whether the therapeutic virus is introduced before the lethal virus or after the lethal virus. The therapeutic virus increases in both cases but by different mechanisms. With the therapeutic virus introduced first, it spreads infectiously without any appreciable change in host dynamics. With the therapeutic virus introduced second, host abundance is depressed at the time therapy is applied; following an initial period of therapeutic virus spread by infection, the subsequent rise of protection is through reproduction by hosts already protected. This latter outcome is due to inheritance of the therapeutic virus state when the protected cell divides. Overall, the work establishes the feasibility and robustness to details of a viral interference using a therapeutic virus.

Experimental Respiratory Infection of Marmosets (Callithrix jacchus) With Ebola Virus Kikwit.

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Smither, Sophie J; Nelson, Michelle; Eastaugh, Lin; Nunez, Alejandro; Salguero, Francisco J; Lever, Mark S

2015-10-01

Ebola virus (EBOV) causes a highly infectious and lethal hemorrhagic fever in primates with high fatality rates during outbreaks and EBOV may be exploited as a potential biothreat pathogen. There is therefore a need to develop and license appropriate medical countermeasures against this virus. To determine whether the common marmoset (Callithrix jacchus) would be an appropriate model to assess vaccines or therapies against EBOV disease (EVD), initial susceptibility, lethality and pathogenesis studies were performed. Low doses of EBOV-Kikwit, between 4 and 27 times the 50% tissue culture infectious dose, were sufficient to cause a lethal, reproducible infection. Animals became febrile between days 5 and 6, maintaining a high fever before succumbing to EVD between 6 and 8 days after challenge. Typical signs of EVD were observed. Pathogenesis studies revealed that virus was isolated from the lungs of animals beginning on day 3 after challenge and from the liver, spleen and blood beginning on day 5. The most striking features were observed in animals that succumbed to infection, including high viral titers in all organs, increased levels of liver function enzymes and blood clotting times, decreased levels of platelets, multifocal moderate to severe hepatitis, and perivascular edema. © Crown copyright 2015.

DNA vaccines elicit durable protective immunity against individual or simultaneous infections with Lassa and Ebola viruses in guinea pigs

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Cashman, Kathleen A.; Wilkinson, Eric R.; Wollen, Suzanne E.; Shamblin, Joshua D.; Zelko, Justine M.; Bearss, Jeremy J.; Zeng, Xiankun; Broderick, Kate E.; Schmaljohn, Connie S.

2017-01-01

ABSTRACT We previously developed optimized DNA vaccines against both Lassa fever and Ebola hemorrhagic fever viruses and demonstrated that they were protective individually in guinea pig and nonhuman primate models. In this study, we vaccinated groups of strain 13 guinea pigs two times, four weeks apart with 50 µg of each DNA vaccine or a mock vaccine at discrete sites by intradermal electroporation. Five weeks following the second vaccinations, guinea pigs were exposed to lethal doses of Lassa virus, Ebola virus, or a combination of both viruses simultaneously. None of the vaccinated guinea pigs, regardless of challenge virus and including the coinfected group, displayed weight loss, fever or other disease signs, and all survived to the study endpoint. All of the mock-vaccinated guinea pigs that were infected with Lassa virus, and all but one of the EBOV-infected mock-vaccinated guinea pigs succumbed. In order to determine if the dual-agent vaccination strategy could protect against both viruses if exposures were temporally separated, we held the surviving vaccinates in BSL-4 for approximately 120 days to perform a cross-challenge experiment in which guinea pigs originally infected with Lassa virus received a lethal dose of Ebola virus and those originally infected with Ebola virus were infected with a lethal dose of Lassa virus. All guinea pigs remained healthy and survived to the study endpoint. This study clearly demonstrates that DNA vaccines against Lassa and Ebola viruses can elicit protective immunity against both individual virus exposures as well as in a mixed-infection environment. PMID:29135337

Efficacy of single dose of a bivalent vaccine containing inactivated Newcastle disease virus and reassortant highly pathogenic avian influenza H5N1 virus against lethal HPAI and NDV infection in chickens.

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Dong-Hun Lee

Full Text Available Highly pathogenic avian influenza (HPAI and Newcastle disease (ND are 2 devastating diseases of poultry, which cause great economic losses to the poultry industry. In the present study, we developed a bivalent vaccine containing antigens of inactivated ND and reassortant HPAI H5N1 viruses as a candidate poultry vaccine, and we evaluated its immunogenicity and protective efficacy in specific pathogen-free chickens. The 6:2 reassortant H5N1 vaccine strain containing the surface genes of the A/Chicken/Korea/ES/2003(H5N1 virus was successfully generated by reverse genetics. A polybasic cleavage site of the hemagglutinin segment was replaced by a monobasic cleavage site. We characterized the reverse genetics-derived reassortant HPAI H5N1 clade 2.5 vaccine strain by evaluating its growth kinetics in eggs, minimum effective dose in chickens, and cross-clade immunogenicity against HPAI clade 1 and 2. The bivalent vaccine was prepared by emulsifying inactivated ND (La Sota strain and reassortant HPAI viruses with Montanide ISA 70 adjuvant. A single immunization with this vaccine induced high levels of hemagglutination-inhibiting antibody titers and protected chickens against a lethal challenge with the wild-type HPAI and ND viruses. Our results demonstrate that the bivalent, inactivated vaccine developed in this study is a promising approach for the control of both HPAI H5N1 and ND viral infections.

Post-exposure Treatment with Anti-rabies VHH and Vaccine Significantly Improves Protection of Mice from Lethal Rabies Infection

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Terryn, Sanne; Francart, Aurélie; Rommelaere, Heidi; Stortelers, Catelijne; Van Gucht, Steven

2016-01-01

Post-exposure prophylaxis (PEP) against rabies infection consists of a combination of passive immunisation with plasma-derived human or equine immune globulins and active immunisation with vaccine delivered shortly after exposure. Since anti-rabies immune globulins are expensive and scarce, there is a need for cheaper alternatives that can be produced more consistently. Previously, we generated potent virus-neutralising VHH, also called Nanobodies, against the rabies glycoprotein that are effectively preventing lethal disease in an in vivo mouse model. The VHH domain is the smallest antigen-binding functional fragment of camelid heavy chain-only antibodies that can be manufactured in microbial expression systems. In the current study we evaluated the efficacy of half-life extended anti-rabies VHH in combination with vaccine for PEP in an intranasal rabies infection model in mice. The PEP combination therapy of systemic anti-rabies VHH and intramuscular vaccine significantly delayed the onset of disease compared to treatment with anti-rabies VHH alone, prolonged median survival time (35 versus 14 days) and decreased mortality (60% versus 19% survival rate), when treated 24 hours after rabies virus challenge. Vaccine alone was unable to rescue mice from lethal disease. As reported also for immune globulins, some interference of anti-rabies VHH with the antigenicity of the vaccine was observed, but this did not impede the synergistic effect. Post exposure treatment with vaccine and human anti-rabies immune globulins was unable to protect mice from lethal challenge. Anti-rabies VHH and vaccine act synergistically to protect mice after rabies virus exposure, which further validates the possible use of anti-rabies VHH for rabies PEP. PMID:27483431

Post-exposure Treatment with Anti-rabies VHH and Vaccine Significantly Improves Protection of Mice from Lethal Rabies Infection.

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Sanne Terryn

2016-08-01

Full Text Available Post-exposure prophylaxis (PEP against rabies infection consists of a combination of passive immunisation with plasma-derived human or equine immune globulins and active immunisation with vaccine delivered shortly after exposure. Since anti-rabies immune globulins are expensive and scarce, there is a need for cheaper alternatives that can be produced more consistently. Previously, we generated potent virus-neutralising VHH, also called Nanobodies, against the rabies glycoprotein that are effectively preventing lethal disease in an in vivo mouse model. The VHH domain is the smallest antigen-binding functional fragment of camelid heavy chain-only antibodies that can be manufactured in microbial expression systems. In the current study we evaluated the efficacy of half-life extended anti-rabies VHH in combination with vaccine for PEP in an intranasal rabies infection model in mice. The PEP combination therapy of systemic anti-rabies VHH and intramuscular vaccine significantly delayed the onset of disease compared to treatment with anti-rabies VHH alone, prolonged median survival time (35 versus 14 days and decreased mortality (60% versus 19% survival rate, when treated 24 hours after rabies virus challenge. Vaccine alone was unable to rescue mice from lethal disease. As reported also for immune globulins, some interference of anti-rabies VHH with the antigenicity of the vaccine was observed, but this did not impede the synergistic effect. Post exposure treatment with vaccine and human anti-rabies immune globulins was unable to protect mice from lethal challenge. Anti-rabies VHH and vaccine act synergistically to protect mice after rabies virus exposure, which further validates the possible use of anti-rabies VHH for rabies PEP.

Chimeric vaccine composed of viral peptide and mammalian heat-shock protein 60 peptide protects against West Nile virus challenge.

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Gershoni-Yahalom, Orly; Landes, Shimon; Kleiman-Shoval, Smadar; Ben-Nathan, David; Kam, Michal; Lachmi, Bat-El; Khinich, Yevgeny; Simanov, Michael; Samina, Itzhak; Eitan, Anat; Cohen, Irun R; Rager-Zisman, Bracha; Porgador, Angel

2010-08-01

The protective efficacy and immunogenicity of a chimeric peptide against West Nile virus (WNV) was evaluated. This virus is the aetiological agent of West Nile fever, which has recently emerged in the western hemisphere. The rapid spread of WNV throughout North America, as well as the constantly changing epidemiology and transmission of the virus by blood transfusion and transplantation, have raised major public-health concerns. Currently, there are no effective treatments for WNV or vaccine for human use. We previously identified a novel, continuous B-cell epitope from domain III of the WNV envelope protein, termed Ep15. To test whether this epitope can protect against WNV infection, we synthesized a linear chimeric peptide composed of Ep15 and the heat-shock protein 60 peptide, p458. The p458 peptide is an effective carrier peptide for subunit vaccines against other infectious agents. We now report that mice immunized with the chimeric peptide, p458-Ep15, were resistant to lethal challenges with three different WNV strains. Moreover, their brains were free of viral genome and infectious virus. Mice immunized with Ep15 alone or with p431-Ep15, a control conjugate, were not protected. The chimeric p458-Ep15 peptide induced WNV-specific immunoglobulin G antibodies that neutralized the virus and induced the secretion of interferon-gammain vitro. Challenge of chimeric peptide-immunized mice considerably enhanced WNV-specific neutralizing antibodies. We conclude that this chimeric peptide can be used for formulation of a human vaccine against WNV.

Memory CD8 T cells mediate severe immunopathology following respiratory syncytial virus infection.

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Megan E Schmidt

2018-01-01

Full Text Available Memory CD8 T cells can provide protection from re-infection by respiratory viruses such as influenza and SARS. However, the relative contribution of memory CD8 T cells in providing protection against respiratory syncytial virus (RSV infection is currently unclear. To address this knowledge gap, we utilized a prime-boost immunization approach to induce robust memory CD8 T cell responses in the absence of RSV-specific CD4 T cells and antibodies. Unexpectedly, RSV infection of mice with pre-existing CD8 T cell memory led to exacerbated weight loss, pulmonary disease, and lethal immunopathology. The exacerbated disease in immunized mice was not epitope-dependent and occurred despite a significant reduction in RSV viral titers. In addition, the lethal immunopathology was unique to the context of an RSV infection as mice were protected from a normally lethal challenge with a recombinant influenza virus expressing an RSV epitope. Memory CD8 T cells rapidly produced IFN-γ following RSV infection resulting in elevated protein levels in the lung and periphery. Neutralization of IFN-γ in the respiratory tract reduced morbidity and prevented mortality. These results demonstrate that in contrast to other respiratory viruses, RSV-specific memory CD8 T cells can induce lethal immunopathology despite mediating enhanced viral clearance.

MDA5 can be exploited as efficacious genetic adjuvant for DNA vaccination against lethal H5N1 influenza virus infection in chickens.

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Matthias Liniger

Full Text Available Chickens lack the retinoic acid-inducible gene I (RIG-I and sense avian influenza virus (AIV infections by means of the melanoma differentiation-associated gene 5 product (chMDA5. Plasmid-driven expression of the N-terminal half of chMDA5 containing the caspase activation and recruitment domains [chMDA5(1-483] triggers interferon-β responses in chicken cells. We hypothesized that mimicking virus infection by chMDA5(1-483 expression may enhance vaccine-induced adaptive immunity. In order to test this, the potential genetic adjuvant properties of chMDA5(1-483 were evaluated in vivo in combination with a suboptimal quantity of a plasmid DNA vaccine expressing haemagglutinin (HA of H5N1 AIV. Co-administration of the HA plasmid with plasmid DNA for chMDA5(1-483 expression resulted in approximately 10-fold higher HA-specific antibody responses than injection of the HA plasmid mixed with empty vector DNA as control. Accordingly, compared with HA DNA vaccination alone, the chMDA5(1-483-adjuvanted HA DNA vaccine mediated enhanced protection against a lethal H5N1 challenge infection in chickens, with reduced clinical signs and cloacal virus shedding. These data demonstrate that innate immune activation by expression of signaling domains of RIG-I-like receptors can be exploited to enhance vaccine efficacy.

Efficacy of oral active ether lipid analogs of cidofovir in a lethal mousepox model

International Nuclear Information System (INIS)

Buller, R. Mark; Owens, Gelita; Schriewer, Jill; Melman, Lora; Beadle, James R.; Hostetler, Karl Y.

2004-01-01

Cidofovir (CDV) is a highly effective inhibitor of orthopoxvirus replication and may be used intravenously to treat smallpox or complications arising from the smallpox vaccine under an investigational new drug application (IND). However, CDV is absorbed poorly following oral administration and is inactive orally. To improve the bioavailability of CDV, others synthesized alkoxyalkanol esters of CDV and observed >100-fold more activity than unmodified CDV against cowpox, vaccinia, and variola virus (VARV) replication. These ether lipid analogs of CDV have high oral bioavailability in mice. In this study, we compared the oral activity of CDV with the hexadecyloxypropyl (HDP)-, octadecyloxyethyl-, oleyloxypropyl-, and oleyloxyethyl-esters of CDV in a lethal, aerosol ectromelia virus (ECTV) challenge model in A/NCR mice. Octadecyloxyethyl-CDV appeared to be the most potent CDV analog as a dose regimen of 5 mg/kg started 4 h following challenge completely blocked virus replication in spleen and liver, and protected 100% of A/NCR mice, although oral, unmodified CDV was inactive. These results suggest that this family of compounds deserves further evaluation as poxvirus antiviral

Inactivated recombinant plant virus protects dogs from a lethal challenge with canine parvovirus

DEFF Research Database (Denmark)

Langeveld, J.P.M.; Brennan, F.R.; Martinez-Torrecuadrada, J.L.

2001-01-01

A vaccine based upon a recombinant plant virus (CPMV-PARVO1), displaying a peptide derived from the VP2 capsid protein of canine parvovirus (CPV), has previously been described. To date, studies with the vaccine have utilized viable plant chimaeric particles (CVPs). In this study, CPMV-PARVO1...

Chemical modifications of antisense morpholino oligomers enhance their efficacy against Ebola virus infection.

Science.gov (United States)

Swenson, Dana L; Warfield, Kelly L; Warren, Travis K; Lovejoy, Candace; Hassinger, Jed N; Ruthel, Gordon; Blouch, Robert E; Moulton, Hong M; Weller, Dwight D; Iversen, Patrick L; Bavari, Sina

2009-05-01

Phosphorodiamidate morpholino oligomers (PMOs) are uncharged nucleic acid-like molecules designed to inactivate the expression of specific genes via the antisense-based steric hindrance of mRNA translation. PMOs have been successful at knocking out viral gene expression and replication in the case of acute viral infections in animal models and have been well tolerated in human clinical trials. We propose that antisense PMOs represent a promising class of therapeutic agents that may be useful for combating filoviral infections. We have previously shown that mice treated with a PMO whose sequence is complementary to a region spanning the start codon of VP24 mRNA were protected against lethal Ebola virus challenge. In the present study, we report on the abilities of two additional VP24-specific PMOs to reduce the cell-free translation of a VP24 reporter, to inhibit the in vitro replication of Ebola virus, and to protect mice against lethal challenge when the PMOs are delivered prior to infection. Additionally, structure-activity relationship evaluations were conducted to assess the enhancement of antiviral efficacy associated with PMO chemical modifications that included conjugation with peptides of various lengths and compositions, positioning of conjugated peptides to either the 5' or the 3' terminus, and the conferring of charge modifications by the addition of piperazine moieties. Conjugation with arginine-rich peptides greatly enhanced the antiviral efficacy of VP24-specific PMOs in infected cells and mice during lethal Ebola virus challenge.

Differentiation of strains of yellow fever virus in γ-irradiated mice

International Nuclear Information System (INIS)

Fitzgeorge, R.; Bradish, C.J.

1980-01-01

The mouse sensitized by optimal, sub-lethal γ-irradiation has been used for the differentiation of strains of yellow fever virus and for the resolution of their immunogenicity and pathogenicity as distinct characteristics. For different strains of yellow fever virus, the patterns of antibody-synthesis, regulatory immunity (pre-challenge) and protective immunity (post-challenge) are differentially sensitive to γ-irradiation. These critical differentiations of strains of yellow fever virus in γ-irradiated mice have been compared with those shown in normal athymic and immature mice in order to elucidate the range of quantifiable in vivo characteristics and the course of the virus-host interaction. This is discussed as a basis for the comparisons of the responses of model and principal hosts to vaccines and pathogens. (author)

Daily ingestion of the probiotic Lactobacillus paracasei ST11 decreases Vaccinia virus dissemination and lethality in a mouse model.

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Dos Santos Pereira Andrade, A C; Lima, M Teixeira; Oliveira, G Pereira; Calixto, R Silva; de Sales E Souza, É Lorenna; da Glória de Souza, D; de Almeida Leite, C M; Ferreira, J M Siqueira; Kroon, E G; de Oliveira, D Bretas; Dos Santos Martins, F; Abrahão, J S

2017-02-07

Vaccinia virus (VACV) is an important pathogen. Although studies have shown relationships between probiotics and viruses, the effect of probiotics on VACV infection is unknown. Therefore, this work aims to investigate the probiotics effects on VACV infection. Mice were divided into four groups, two non-infected groups, one receiving the probiotic, the other one not receiving it, and two groups infected intranasally with VACV Western Reserve (VACV-WR) receiving or not receiving the probiotic. Viral titres in organs and cytokine production in the lungs were analysed. Lung samples were also subjected to histological analysis. The intake of probiotic results in reduction in viral spread with a significant decrease of VACV titer on lung, liver and brain of treated group. In addition,treatment with the probiotic results in attenuated mice lung inflammation showing fewer lesions on histological findings and decreased lethality in mice infected with VACV. The ingestion of Lactobacillus paracasei ST11 (LPST11) after VACV infection resulted in 2/9 animal lethality compared with 4/9 in the VACV group. This is the first study on probiotics and VACV interactions, providing not only information about this interaction, but also proposing a model for future studies involving probiotics and other poxvirus.

BoHV-4-Based Vector Single Heterologous Antigen Delivery Protects STAT1(-/- Mice from Monkeypoxvirus Lethal Challenge.

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Valentina Franceschi

2015-06-01

Full Text Available Monkeypox virus (MPXV is the etiological agent of human (MPX. It is an emerging orthopoxvirus zoonosis in the tropical rain forest of Africa and is endemic in the Congo-basin and sporadic in West Africa; it remains a tropical neglected disease of persons in impoverished rural areas. Interaction of the human population with wildlife increases human infection with MPX virus (MPXV, and infection from human to human is possible. Smallpox vaccination provides good cross-protection against MPX; however, the vaccination campaign ended in Africa in 1980, meaning that a large proportion of the population is currently unprotected against MPXV infection. Disease control hinges on deterring zoonotic exposure to the virus and, barring that, interrupting person-to-person spread. However, there are no FDA-approved therapies against MPX, and current vaccines are limited due to safety concerns. For this reason, new studies on pathogenesis, prophylaxis and therapeutics are still of great interest, not only for the scientific community but also for the governments concerned that MPXV could be used as a bioterror agent. In the present study, a new vaccination strategy approach based on three recombinant bovine herpesvirus 4 (BoHV-4 vectors, each expressing different MPXV glycoproteins, A29L, M1R and B6R were investigated in terms of protection from a lethal MPXV challenge in STAT1 knockout mice. BoHV-4-A-CMV-A29LgD106ΔTK, BoHV-4-A-EF1α-M1RgD106ΔTK and BoHV-4-A-EF1α-B6RgD106ΔTK were successfully constructed by recombineering, and their capacity to express their transgene was demonstrated. A small challenge study was performed, and all three recombinant BoHV-4 appeared safe (no weight-loss or obvious adverse events following intraperitoneal administration. Further, BoHV-4-A-EF1α-M1RgD106ΔTK alone or in combination with BoHV-4-A-CMV-A29LgD106ΔTK and BoHV-4-A-EF1α-B6RgD106ΔTK, was shown to be able to protect, 100% alone and 80% in combination, STAT1(-/- mice

Interferon-γ Inhibits Ebola Virus Infection.

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Bethany A Rhein

Full Text Available Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

Interferon-γ Inhibits Ebola Virus Infection.

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Rhein, Bethany A; Powers, Linda S; Rogers, Kai; Anantpadma, Manu; Singh, Brajesh K; Sakurai, Yasuteru; Bair, Thomas; Miller-Hunt, Catherine; Sinn, Patrick; Davey, Robert A; Monick, Martha M; Maury, Wendy

2015-01-01

Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

Vaccination of mice using the West Nile virus E-protein in a DNA prime-protein boost strategy stimulates cell-mediated immunity and protects mice against a lethal challenge.

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Marina De Filette

Full Text Available West Nile virus (WNV is a mosquito-borne flavivirus that is endemic in Africa, the Middle East, Europe and the United States. There is currently no antiviral treatment or human vaccine available to treat or prevent WNV infection. DNA plasmid-based vaccines represent a new approach for controlling infectious diseases. In rodents, DNA vaccines have been shown to induce B cell and cytotoxic T cell responses and protect against a wide range of infections. In this study, we formulated a plasmid DNA vector expressing the ectodomain of the E-protein of WNV into nanoparticles by using linear polyethyleneimine (lPEI covalently bound to mannose and examined the potential of this vaccine to protect against lethal WNV infection in mice. Mice were immunized twice (prime--boost regime with the WNV DNA vaccine formulated with lPEI-mannose using different administration routes (intramuscular, intradermal and topical. In parallel a heterologous boost with purified recombinant WNV envelope (E protein was evaluated. While no significant E-protein specific humoral response was generated after DNA immunization, protein boosting of DNA-primed mice resulted in a marked increase in total neutralizing antibody titer. In addition, E-specific IL-4 T-cell immune responses were detected by ELISPOT after protein boost and CD8(+ specific IFN-γ expression was observed by flow cytometry. Challenge experiments using the heterologous immunization regime revealed protective immunity to homologous and virulent WNV infection.

Protection against lethal Marburg virus infection mediated by lipid encapsulated small interfering RNA.

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Ursic-Bedoya, Raul; Mire, Chad E; Robbins, Marjorie; Geisbert, Joan B; Judge, Adam; MacLachlan, Ian; Geisbert, Thomas W

2014-02-15

Marburg virus (MARV) infection causes severe morbidity and mortality in humans and nonhuman primates. Currently, there are no licensed therapeutics available for treating MARV infection. Here, we present the in vitro development and in vivo evaluation of lipid-encapsulated small interfering RNA (siRNA) as a potential therapeutic for the treatment of MARV infection. The activity of anti-MARV siRNAs was assessed using dual luciferase reporter assays followed by in vitro testing against live virus. Lead candidates were tested in lethal guinea pig models of 3 different MARV strains (Angola, Ci67, Ravn). Treatment resulted in 60%-100% survival of guinea pigs infected with MARV. Although treatment with siRNA targeting other MARV messenger RNA (mRNA) had a beneficial effect, targeting the MARV NP mRNA resulted in the highest survival rates. NP-718m siRNA in lipid nanoparticles provided 100% protection against MARV strains Angola and Ci67, and 60% against Ravn. A cocktail containing NP-718m and NP-143m provided 100% protection against MARV Ravn. These data show protective efficacy against the most pathogenic Angola strain of MARV. Further development of the lipid nanoparticle technology has the potential to yield effective treatments for MARV infection.

New Orf virus (Parapoxvirus) recombinant expressing H5 hemagglutinin protects mice against H5N1 and H1N1 influenza A virus.

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Rohde, Jörg; Amann, Ralf; Rziha, Hanns-Joachim

2013-01-01

Previously we demonstrated the versatile utility of the Parapoxvirus Orf virus (ORFV) as a vector platform for the development of potent recombinant vaccines. In this study we present the generation of new ORFV recombinants expressing the hemagglutinin (HA) or nucleoprotein (NP) of the highly pathogenic avian influenza virus (HPAIV) H5N1. Correct foreign gene expression was examined in vitro by immunofluorescence, Western blotting and flow cytometry. The protective potential of both recombinants was evaluated in the mouse challenge model. Despite adequate expression of NP, the recombinant D1701-V-NPh5 completely failed to protect mice from lethal challenge. However, the H5 HA-expressing recombinant D1701-V-HAh5n mediated solid protection in a dose-dependent manner. Two intramuscular (i.m.) injections of the HA-expressing recombinant protected all animals from lethal HPAIV infection without loss of body weight. Notably, the immunized mice resisted cross-clade H5N1 and heterologous H1N1 (strain PR8) influenza virus challenge. In vivo antibody-mediated depletion of CD4-positive and/or CD8-posititve T-cell subpopulations during immunization and/or challenge infection implicated the relevance of CD4-positive T-cells for induction of protective immunity by D1701-V-HAh5n, whereas the absence of CD8-positive T-cells did not significantly influence protection. In summary, this study validates the potential of the ORFV vectored vaccines also to combat HPAIV.

New Orf virus (Parapoxvirus recombinant expressing H5 hemagglutinin protects mice against H5N1 and H1N1 influenza A virus.

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Jörg Rohde

Full Text Available Previously we demonstrated the versatile utility of the Parapoxvirus Orf virus (ORFV as a vector platform for the development of potent recombinant vaccines. In this study we present the generation of new ORFV recombinants expressing the hemagglutinin (HA or nucleoprotein (NP of the highly pathogenic avian influenza virus (HPAIV H5N1. Correct foreign gene expression was examined in vitro by immunofluorescence, Western blotting and flow cytometry. The protective potential of both recombinants was evaluated in the mouse challenge model. Despite adequate expression of NP, the recombinant D1701-V-NPh5 completely failed to protect mice from lethal challenge. However, the H5 HA-expressing recombinant D1701-V-HAh5n mediated solid protection in a dose-dependent manner. Two intramuscular (i.m. injections of the HA-expressing recombinant protected all animals from lethal HPAIV infection without loss of body weight. Notably, the immunized mice resisted cross-clade H5N1 and heterologous H1N1 (strain PR8 influenza virus challenge. In vivo antibody-mediated depletion of CD4-positive and/or CD8-posititve T-cell subpopulations during immunization and/or challenge infection implicated the relevance of CD4-positive T-cells for induction of protective immunity by D1701-V-HAh5n, whereas the absence of CD8-positive T-cells did not significantly influence protection. In summary, this study validates the potential of the ORFV vectored vaccines also to combat HPAIV.

Broadly-reactive human monoclonal antibodies elicited following pandemic H1N1 influenza virus exposure protect mice from highly pathogenic H5N1 challenge.

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Nachbagauer, Raffael; Shore, David; Yang, Hua; Johnson, Scott K; Gabbard, Jon D; Tompkins, S Mark; Wrammert, Jens; Wilson, Patrick C; Stevens, James; Ahmed, Rafi; Krammer, Florian; Ellebedy, Ali H

2018-06-13

Broadly cross-reactive antibodies that recognize conserved epitopes within the influenza virus hemagglutinin (HA) stalk domain are of particular interest for their potential use as therapeutic and prophylactic agents against multiple influenza virus subtypes including zoonotic virus strains. Here, we characterized four human HA stalk-reactive monoclonal antibodies (mAbs) for their binding breadth and affinity, in vitro neutralization capacity, and in vivo protective potential against an highly pathogenic avian influenza virus. The monoclonal antibodies were isolated from individuals shortly following infection with (70-1F02 and 1009-3B05) or vaccination against (05-2G02 and 09-3A01) A(H1N1)pdm09. Three of the mAbs bound HAs from multiple strains of group 1 viruses, and one mAb, 05-2G02, bound to both group 1 and group 2 influenza A HAs. All four antibodies prophylactically protected mice against a lethal challenge with the highly pathogenic A/Vietnam/1203/04 (H5N1) strain. Two mAbs, 70-1F02 and 09-3A01, were further tested for their therapeutic efficacy against the same strain and showed good efficacy in this setting as well. One mAb, 70-1F02, was co-crystallized with H5 HA and showed similar heavy chain only interactions as a the previously described anti-stalk antibody CR6261. Finally, we showed that antibodies that compete with these mAbs are prevalent in serum from an individual recently infected with A(H1N1)pdm09 virus. The antibodies described here can be developed into broad-spectrum antiviral therapeutics that could be used to combat infections with zoonotic or emerging pandemic influenza viruses. IMPORTANCE The rise in zoonotic infections of humans with emerging influenza viruses is a worldwide public health concern. The majority of recent zoonotic human influenza cases were caused by H7N9 and H5Nx viruses and were associated with high morbidity and mortality. In addition, seasonal influenza viruses are estimated to cause up to 650,000 deaths annually

Characterization of Lethal Zika Virus Infection in AG129 Mice.

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Matthew T Aliota

2016-04-01

Full Text Available Mosquito-borne Zika virus (ZIKV typically causes a mild and self-limiting illness known as Zika fever, which often is accompanied by maculopapular rash, headache, and myalgia. During the current outbreak in South America, ZIKV infection during pregnancy has been hypothesized to cause microcephaly and other diseases. The detection of ZIKV in fetal brain tissue supports this hypothesis. Because human infections with ZIKV historically have remained sporadic and, until recently, have been limited to small-scale epidemics, neither the disease caused by ZIKV nor the molecular determinants of virulence and/or pathogenicity have been well characterized. Here, we describe a small animal model for wild-type ZIKV of the Asian lineage.Using mice deficient in interferon α/β and Ɣ receptors (AG129 mice, we report that these animals were highly susceptible to ZIKV infection and disease, succumbing within seven to eight days. Rapid viremic dissemination was observed in visceral organs and brain; but only was associated with severe pathologies in the brain and muscle. Finally, these results were consistent across challenge routes, age of mice, and inoculum doses. These data represent a mouse model for ZIKV that is not dependent on adapting ZIKV to intracerebral passage in mice.Foot pad injection of AG129 mice with ZIKV represents a biologically relevant model for studying ZIKV infection and disease development following wild-type virus inoculation without the requirement for adaptation of the virus or intracerebral delivery of the virus. This newly developed Zika disease model can be exploited to identify determinants of ZIKV virulence and reveal molecular mechanisms that control the virus-host interaction, providing a framework for rational design of acute phase therapeutics and for vaccine efficacy testing.

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

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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.

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

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Anthony C Marriott

Full Text Available 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.

Variability in mutational fitness effects prevents full lethal transitions in large quasispecies populations

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Sardanyés, Josep; Simó, Carles; Martínez, Regina; Solé, Ricard V.; Elena, Santiago F.

2014-04-01

The distribution of mutational fitness effects (DMFE) is crucial to the evolutionary fate of quasispecies. In this article we analyze the effect of the DMFE on the dynamics of a large quasispecies by means of a phenotypic version of the classic Eigen's model that incorporates beneficial, neutral, deleterious, and lethal mutations. By parameterizing the model with available experimental data on the DMFE of Vesicular stomatitis virus (VSV) and Tobacco etch virus (TEV), we found that increasing mutation does not totally push the entire viral quasispecies towards deleterious or lethal regions of the phenotypic sequence space. The probability of finding regions in the parameter space of the general model that results in a quasispecies only composed by lethal phenotypes is extremely small at equilibrium and in transient times. The implications of our findings can be extended to other scenarios, such as lethal mutagenesis or genomically unstable cancer, where increased mutagenesis has been suggested as a potential therapy.

B cells are not essential for Lactobacillus-mediated protection against lethal pneumovirus infection.

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Percopo, Caroline M; Dyer, Kimberly D; Garcia-Crespo, Katia E; Gabryszewski, Stanislaw J; Shaffer, Arthur L; Domachowske, Joseph B; Rosenberg, Helene F

2014-06-01

We have shown previously that priming of respiratory mucosa with live Lactobacillus species promotes robust and prolonged survival from an otherwise lethal infection with pneumonia virus of mice, a property known as heterologous immunity. Lactobacillus priming results in a moderate reduction in virus recovery and a dramatic reduction in virus-induced proinflammatory cytokine production; the precise mechanisms underlying these findings remain to be elucidated. Because B cells have been shown to promote heterologous immunity against respiratory virus pathogens under similar conditions, in this study we explore the role of B cells in Lactobacillus-mediated protection against acute pneumovirus infection. We found that Lactobacillus-primed mice feature elevated levels of airway Igs IgG, IgA, and IgM and lung tissues with dense, B cell (B220(+))-enriched peribronchial and perivascular infiltrates with germinal centers consistent with descriptions of BALT. No B cells were detected in lung tissue of Lactobacillus-primed B cell deficient μMT mice or Jh mice, and Lactobacillus-primed μMT mice had no characteristic infiltrates or airway Igs. Nonetheless, we observed diminished virus recovery and profound suppression of virus-induced proinflammatory cytokines CCL2, IFN-γ, and CXCL10 in both wild-type and Lactobacillus-primed μMT mice. Furthermore, Lactobacillus plantarum-primed, B cell-deficient μMT and Jh mice were fully protected from an otherwise lethal pneumonia virus of mice infection, as were their respective wild-types. We conclude that B cells are dispensable for Lactobacillus-mediated heterologous immunity and were not crucial for promoting survival in response to an otherwise lethal pneumovirus infection.

The Nerium oleander aphid Aphis nerii is tolerant to a local isolate of Aphid lethal paralysis virus (ALPV).

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Dombrovsky, Aviv; Luria, Neta

2013-04-01

In a survey that was conducted during the year 2011, a local strain of Aphid lethal paralysis virus (ALPV) was identified and isolated from a wild population of Aphis nerii aphids living on Nerium oleander plants located in northern Israel. The new strain was tentatively named (ALPV-An). RNA extracted from the viral particles allowed the amplification and determination of the complete genome sequence. The virus genome is comprised of 9835 nucleotides. In a BLAST search analysis, the ALPV-An sequence showed 89 % nucleotide sequence identity with the whole genome of a South African ALPV and 96 and 94 % amino acid sequence identity with the ORF1 and ORF2 of that strain, respectively. In preliminary experiments, spray-applied, purified ALPV virions were highly pathogenic to the green peach aphid Myzus persicae; 95 % mortality was recorded 4 days post-infection. These preliminary results demonstrate the potential of ALPV for use as a biologic agent for some aphid control. Surprisingly, no visible ALPV pathogenic effects, such as morphological changes or paralysis, were observed in the A. nerii aphids infected with ALPV-An. The absence of clear ALPV symptoms in A. nerii led to the formulation of two hypotheses, which were partially examined in this study. The first hypothesis suggest that A. nerii is resistant or tolerant of ALPV, while the second hypothesis propose that ALPV-An may be a mild strain of ALPV. Currently, our results is in favor with the first hypothesis since ALPV-An is cryptic in A. nerii aphids and can be lethal for M. persicae aphids.

Early death after feline infectious peritonitis virus challenge due to recombinant vaccinia virus immunization.

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Vennema, H; de Groot, R J; Harbour, D A; Dalderup, M; Gruffydd-Jones, T; Horzinek, M C; Spaan, W J

1990-01-01

The gene encoding the fusogenic spike protein of the coronavirus causing feline infectious peritonitis was recombined into the genome of vaccinia virus. The recombinant induced spike-protein-specific, in vitro neutralizing antibodies in mice. When kittens were immunized with the recombinant, low titers of neutralizing antibodies were obtained. After challenge with feline infectious peritonitis virus, these animals succumbed earlier than did the control group immunized with wild-type vaccinia virus (early death syndrome). Images PMID:2154621

Sigma virus and mutation in Drosophila melanogaster

International Nuclear Information System (INIS)

Paquin, S.L.A.

1977-01-01

- The objectives of these experiments have been (1) to verify and evidence more fully the action of sigma in causing recessive lethal mutation on the X chromosome of Drosophila, both in the male and the female germ line; (2) to extend the study of sigma-induced recessive lethal mutation to the Drosophila autosomes; (3) to explore the possibility that this mutagenesis is site-directed; (4) to study the effects of sigma virus in conjunction with radiation in increasing non-disjunction and dominant lethality. The virus increases the rate of radiation-induced nondisjunction by altering meiotic chromosomal behavior. Percentage of non-disjunction with 500 rads of x-rays in the virus-free flies was 0.176, while in sigma-containing lines it was 0.333. With high doses of either x or neutron radiation, the presence of the virus enhances the frequency of dominant lethality. The difference is especially significant with the fast neutrons. The results indicate that sigma, and presumably other viruses, are indeed environmental mutagens and are, therefore, factors in the rate of background or spontaneous mutation

Efficacy of Recombinant Canine Distemper Virus Expressing Leishmania Antigen against Leishmania Challenge in Dogs.

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Miura, Ryuichi; Kooriyama, Takanori; Yoneda, Misako; Takenaka, Akiko; Doki, Miho; Goto, Yasuyuki; Sanjoba, Chizu; Endo, Yasuyuki; Fujiyuki, Tomoko; Sugai, Akihiro; Tsukiyama-Kohara, Kyoko; Matsumoto, Yoshitsugu; Sato, Hiroki; Kai, Chieko

2015-01-01

Canine distemper virus (CDV) vaccination confers long-term protection against CDV reinfection. To investigate the utility of CDV as a polyvalent vaccine vector for Leishmania, we generated recombinant CDVs, based on an avirulent Yanaka strain, that expressed Leishmania antigens: LACK, TSA, or LmSTI1 (rCDV-LACK, rCDV-TSA, and rCDV-LmSTI1, respectively). Dogs immunized with rCDV-LACK were protected against challenge with lethal doses of virulent CDV, in the same way as the parental Yanaka strain. To evaluate the protective effects of the recombinant CDVs against cutaneous leishmaniasis in dogs, dogs were immunized with one recombinant CDV or a cocktail of three recombinant CDVs, before intradermal challenge (in the ears) with infective-stage promastigotes of Leishmania major. Unvaccinated dogs showed increased nodules with ulcer formation after 3 weeks, whereas dogs immunized with rCDV-LACK showed markedly smaller nodules without ulceration. Although the rCDV-TSA- and rCDV-LmSTI1-immunized dogs showed little protection against L. major, the cocktail of three recombinant CDVs more effectively suppressed the progression of nodule formation than immunization with rCDV-LACK alone. These results indicate that recombinant CDV is suitable for use as a polyvalent live attenuated vaccine for protection against both CDV and L. major infections in dogs.

Intravenous inoculation of a bat-associated rabies virus causes lethal encephalopathy in mice through invasion of the brain via neurosecretory hypothalamic fibers.

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Mirjam A R Preuss

2009-06-01

Full Text Available The majority of rabies virus (RV infections are caused by bites or scratches from rabid carnivores or bats. Usually, RV utilizes the retrograde transport within the neuronal network to spread from the infection site to the central nervous system (CNS where it replicates in neuronal somata and infects other neurons via trans-synaptic spread. We speculate that in addition to the neuronal transport of the virus, hematogenous spread from the site of infection directly to the brain after accidental spill over into the vascular system might represent an alternative way for RV to invade the CNS. So far, it is unknown whether hematogenous spread has any relevance in RV pathogenesis. To determine whether certain RV variants might have the capacity to invade the CNS from the periphery via hematogenous spread, we infected mice either intramuscularly (i.m. or intravenously (i.v. with the dog-associated RV DOG4 or the silver-haired bat-associated RV SB. In addition to monitoring the progression of clinical signs of rabies we used immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR to follow the spread of the virus from the infection site to the brain. In contrast to i.m. infection where both variants caused a lethal encephalopathy, only i.v. infection with SB resulted in the development of a lethal infection. While qRT-PCR did not reveal major differences in virus loads in spinal cord or brain at different times after i.m. or i.v. infection of SB, immunohistochemical analysis showed that only i.v. administered SB directly infected the forebrain. The earliest affected regions were those hypothalamic nuclei, which are connected by neurosecretory fibers to the circumventricular organs neurohypophysis and median eminence. Our data suggest that hematogenous spread of SB can lead to a fatal encephalopathy through direct retrograde invasion of the CNS at the neurovascular interface of the hypothalamus-hypophysis system

Enhanced protection against Ebola virus mediated by an improved adenovirus-based vaccine.

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Richardson, Jason S; Yao, Michel K; Tran, Kaylie N; Croyle, Maria A; Strong, James E; Feldmann, Heinz; Kobinger, Gary P

2009-01-01

The Ebola virus is transmitted by direct contact with bodily fluids of infected individuals, eliciting death rates as high as 90% among infected humans. Currently, replication defective adenovirus-based Ebola vaccine is being studied in a phase I clinical trial. Another Ebola vaccine, based on an attenuated vesicular stomatitis virus has shown efficacy in post-exposure treatment of nonhuman primates to Ebola infection. In this report, we modified the common recombinant adenovirus serotype 5-based Ebola vaccine expressing the wild-type ZEBOV glycoprotein sequence from a CMV promoter (Ad-CMVZGP). The immune response elicited by this improved expression cassette vector (Ad-CAGoptZGP) and its ability to afford protection against lethal ZEBOV challenge in mice was compared to the standard Ad-CMVZGP vector. Ad-CMVZGP was previously shown to protect mice, guinea pigs and nonhuman primates from an otherwise lethal challenge of Zaire ebolavirus. The antigenic expression cassette of this vector was improved through codon optimization, inclusion of a consensus Kozak sequence and reconfiguration of a CAG promoter (Ad-CAGoptZGP). Expression of GP from Ad-CAGoptZGP was substantially higher than from Ad-CMVZGP. Ad-CAGoptZGP significantly improved T and B cell responses at doses 10 to 100-fold lower than that needed with Ad-CMVZGP. Additionally, Ad-CAGoptZGP afforded full protections in mice against lethal challenge at a dose 100 times lower than the dose required for Ad-CMVZGP. Finally, Ad-CAGoptZGP induced full protection to mice when given 30 minutes post-challenge. We describe an improved adenovirus-based Ebola vaccine capable of affording post-exposure protection against lethal challenge in mice. The molecular modifications of the new improved vaccine also translated in the induction of significantly enhanced immune responses and complete protection at a dose 100 times lower than with the previous generation adenovirus-based Ebola vaccine. Understanding and improving the

Enhanced protection against Ebola virus mediated by an improved adenovirus-based vaccine.

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Jason S Richardson

Full Text Available BACKGROUND: The Ebola virus is transmitted by direct contact with bodily fluids of infected individuals, eliciting death rates as high as 90% among infected humans. Currently, replication defective adenovirus-based Ebola vaccine is being studied in a phase I clinical trial. Another Ebola vaccine, based on an attenuated vesicular stomatitis virus has shown efficacy in post-exposure treatment of nonhuman primates to Ebola infection. In this report, we modified the common recombinant adenovirus serotype 5-based Ebola vaccine expressing the wild-type ZEBOV glycoprotein sequence from a CMV promoter (Ad-CMVZGP. The immune response elicited by this improved expression cassette vector (Ad-CAGoptZGP and its ability to afford protection against lethal ZEBOV challenge in mice was compared to the standard Ad-CMVZGP vector. METHODOLOGY/PRINCIPAL FINDINGS: Ad-CMVZGP was previously shown to protect mice, guinea pigs and nonhuman primates from an otherwise lethal challenge of Zaire ebolavirus. The antigenic expression cassette of this vector was improved through codon optimization, inclusion of a consensus Kozak sequence and reconfiguration of a CAG promoter (Ad-CAGoptZGP. Expression of GP from Ad-CAGoptZGP was substantially higher than from Ad-CMVZGP. Ad-CAGoptZGP significantly improved T and B cell responses at doses 10 to 100-fold lower than that needed with Ad-CMVZGP. Additionally, Ad-CAGoptZGP afforded full protections in mice against lethal challenge at a dose 100 times lower than the dose required for Ad-CMVZGP. Finally, Ad-CAGoptZGP induced full protection to mice when given 30 minutes post-challenge. CONCLUSIONS/SIGNIFICANCE: We describe an improved adenovirus-based Ebola vaccine capable of affording post-exposure protection against lethal challenge in mice. The molecular modifications of the new improved vaccine also translated in the induction of significantly enhanced immune responses and complete protection at a dose 100 times lower than with the

B cells are not essential for Lactobacillus-mediated protection against lethal pneumovirus infection*

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Percopo, Caroline M.; Dyer, Kimberly D.; Garcia-Crespo, Katia E.; Gabryszewski, Stanislaw J.; Shaffer, Arthur L.; Domachowske, Joseph B.; Rosenberg, Helene F.

2014-01-01

We have shown previously that priming of respiratory mucosa with live Lactobacillus species promotes robust and prolonged survival from an otherwise lethal infection with pneumonia virus of mice (PVM), a property known as heterologous immunity. Lactobacillus-priming results in a moderate reduction in virus recovery and a dramatic reduction in virus-induced proinflammatory cytokine production; the precise mechanisms underlying these findings remain to be elucidated. As B cells have been shown to promote heterologous immunity against respiratory virus pathogens under similar conditions, here we explore the role of B cells in Lactobacillus-mediated protection against acute pneumovirus infection. We found that Lactobacillus-primed mice feature elevated levels of airway immunoglobulins IgG, IgA and IgM and lung tissues with dense, B cell (B220+) enriched peribronchial and perivascular infiltrates with germinal centers consistent with descriptions of bronchus-associated lymphoid tissue. No B cells were detected in lung tissue of Lactobacillus-primed B-cell deficient μMT mice or Jh mice, and Lactobacillus-primed μMT mice had no characteristic infiltrates or airway immunoglobulins. Nonetheless, we observed diminished virus recovery and profound suppression of virus-induced proinflammatory cytokines CCL2, IFN-gamma, and CXCL10 in both wild-type and Lactobacillus-primed μMT mice. Furthermore, L. plantarum-primed, B-cell deficient μMT and Jh mice were fully protected from an otherwise lethal PVM infection, as were their respective wild-types. We conclude that B cells are dispensable for Lactobacillus-mediated heterologous immunity and were not crucial for promoting survival in response to an otherwise lethal pneumovirus infection. PMID:24748495

Newcastle disease virus-based H5 influenza vaccine protects chickens from lethal challenge with a highly pathogenic H5N2 avian influenza virus

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Ma, Jingjiao; Lee, Jinhwa; Liu, Haixia; Mena, Ignacio; Davis, A. Sally; Sunwoo, Sun Young; Lang, Yuekun; Duff, Michael; Morozov, Igor; Li, Yuhao; Yang, Jianmei; García-Sastre, Adolfo; Richt, Juergen A.; Ma, Wenjun

2017-01-01

Since December 2014, Eurasian-origin, highly pathogenic avian influenza H5 viruses including H5N1, H5N2, and H5N8 subtypes (called H5Nx viruses), which belong to the H5 clade 2.3.4.4, have been detected in U.S. wild birds. Subsequently, highly pathogenic H5N2 and H5N8 viruses have caused outbreaks in U.S. domestic poultry. Vaccination is one of the most effective ways to control influenza outbreaks and protect animal and public health. Newcastle disease virus (NDV)-based influenza vaccines ha...

Immunology of Bats and Their Viruses: Challenges and Opportunities

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Schountz, Tony

2014-01-01

Bats are reservoir hosts of several high-impact viruses that cause significant human diseases, including Nipah virus, Marburg virus and rabies virus. They also harbor many other viruses that are thought to have caused disease in humans after spillover into intermediate hosts, including SARS and MERS coronaviruses. As is usual with reservoir hosts, these viruses apparently cause little or no pathology in bats. Despite the importance of bats as reservoir hosts of zoonotic and potentially zoonotic agents, virtually nothing is known about the host/virus relationships; principally because few colonies of bats are available for experimental infections, a lack of reagents, methods and expertise for studying bat antiviral responses and immunology, and the difficulty of conducting meaningful field work. These challenges can be addressed, in part, with new technologies that are species-independent that can provide insight into the interactions of bats and viruses, which should clarify how the viruses persist in nature, and what risk factors might facilitate transmission to humans and livestock. PMID:25494448

Immunology of Bats and Their Viruses: Challenges and Opportunities

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Tony Schountz

2014-12-01

Full Text Available Bats are reservoir hosts of several high-impact viruses that cause significant human diseases, including Nipah virus, Marburg virus and rabies virus. They also harbor many other viruses that are thought to have caused disease in humans after spillover into intermediate hosts, including SARS and MERS coronaviruses. As is usual with reservoir hosts, these viruses apparently cause little or no pathology in bats. Despite the importance of bats as reservoir hosts of zoonotic and potentially zoonotic agents, virtually nothing is known about the host/virus relationships; principally because few colonies of bats are available for experimental infections, a lack of reagents, methods and expertise for studying bat antiviral responses and immunology, and the difficulty of conducting meaningful field work. These challenges can be addressed, in part, with new technologies that are species-independent that can provide insight into the interactions of bats and viruses, which should clarify how the viruses persist in nature, and what risk factors might facilitate transmission to humans and livestock.

Development of a Lethal Intranasal Exposure Model of Ebola Virus in the Cynomolgus Macaque

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Kendra J. Alfson

2017-10-01

Full Text Available Ebola virus (EBOV is a filovirus that can cause Ebola virus disease (EVD. No approved vaccines or therapies exist for filovirus infections, despite an urgent need. The development and testing of effective countermeasures against EBOV requires use of animal models and a thorough understanding of how the model aligns with EVD in humans. The majority of published studies report outcomes of parenteral exposures for emulating needle stick transmission. However, based on data from EVD outbreaks, close contact exposures to infected bodily fluid seems to be one of the primary routes of EBOV transmission. Thus, further work is needed to develop models that represent mucosal exposure. To characterize the outcome of mucosal exposure to EBOV, cynomolgus macaques were exposed to EBOV via intranasal (IN route using the LMA® mucosal atomization device (LMA® MAD. For comparison, four non-human primates (NHPs were exposed to EBOV via intramuscular (IM route. This IN exposure model was uniformly lethal and correlated with a statistically significant delay in time to death when compared to exposure via the IM route. This more closely reflects the timeframes observed in human infections. An IN model of exposure offers an attractive alternative to other models as it can offer insight into the consequences of exposure via a mucosal surface and allows for screening countermeasures via a different exposure route.

New Taastrup-Like virus, Rhabdoviridae, lethal to leafhoppers

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A new viral pathogen (‘Taastrup Virus’) of leafhoppers was discovered. The unclassified virus is a negative sense, single-stranded RNA virus which appears to be a new member of the order Mononegavirales in the family Rhabdoviridae, and thus far it is only the second report of a Taastrup-like virus m...

Successful topical respiratory tract immunization of primates against Ebola virus.

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Bukreyev, Alexander; Rollin, Pierre E; Tate, Mallory K; Yang, Lijuan; Zaki, Sherif R; Shieh, Wun-Ju; Murphy, Brian R; Collins, Peter L; Sanchez, Anthony

2007-06-01

Ebola virus causes outbreaks of severe viral hemorrhagic fever with high mortality in humans. The virus is highly contagious and can be transmitted by contact and by the aerosol route. These features make Ebola virus a potential weapon for bioterrorism and biological warfare. Therefore, a vaccine that induces both systemic and local immune responses in the respiratory tract would be highly beneficial. We evaluated a common pediatric respiratory pathogen, human parainfluenza virus type 3 (HPIV3), as a vaccine vector against Ebola virus. HPIV3 recombinants expressing the Ebola virus (Zaire species) surface glycoprotein (GP) alone or in combination with the nucleocapsid protein NP or with the cytokine adjuvant granulocyte-macrophage colony-stimulating factor were administered by the respiratory route to rhesus monkeys--in which HPIV3 infection is mild and asymptomatic--and were evaluated for immunogenicity and protective efficacy against a highly lethal intraperitoneal challenge with Ebola virus. A single immunization with any construct expressing GP was moderately immunogenic against Ebola virus and protected 88% of the animals against severe hemorrhagic fever and death caused by Ebola virus. Two doses were highly immunogenic, and all of the animals survived challenge and were free of signs of disease and of detectable Ebola virus challenge virus. These data illustrate the feasibility of immunization via the respiratory tract against the hemorrhagic fever caused by Ebola virus. To our knowledge, this is the first study in which topical immunization through respiratory tract achieved prevention of a viral hemorrhagic fever infection in a primate model.

Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

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Blaney, Joseph E; Marzi, Andrea; Willet, Mallory; Papaneri, Amy B; Wirblich, Christoph; Feldmann, Friederike; Holbrook, Michael; Jahrling, Peter; Feldmann, Heinz; Schnell, Matthias J

2013-01-01

We have previously described the generation of a novel Ebola virus (EBOV) vaccine platform based on (a) replication-competent rabies virus (RABV), (b) replication-deficient RABV, or (c) chemically inactivated RABV expressing EBOV glycoprotein (GP). Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

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Joseph E Blaney

Full Text Available We have previously described the generation of a novel Ebola virus (EBOV vaccine platform based on (a replication-competent rabies virus (RABV, (b replication-deficient RABV, or (c chemically inactivated RABV expressing EBOV glycoprotein (GP. Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

Effect of the deletion of genes encoding proteins of the extracellular virion form of vaccinia virus on vaccine immunogenicity and protective effectiveness in the mouse model.

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Clement A Meseda

Full Text Available Antibodies to both infectious forms of vaccinia virus, the mature virion (MV and the enveloped virion (EV, as well as cell-mediated immune response appear to be important for protection against smallpox. EV virus particles, although more labile and less numerous than MV, are important for dissemination and spread of virus in infected hosts and thus important in virus pathogenesis. The importance of the EV A33 and B5 proteins for vaccine induced immunity and protection in a murine intranasal challenge model was evaluated by deletion of both the A33R and B5R genes in a vaccine-derived strain of vaccinia virus. Deletion of either A33R or B5R resulted in viruses with a small plaque phenotype and reduced virus yields, as reported previously, whereas deletion of both EV protein-encoding genes resulted in a virus that formed small infection foci that were detectable and quantifiable only by immunostaining and an even more dramatic decrease in total virus yield in cell culture. Deletion of B5R, either as a single gene knockout or in the double EV gene knockout virus, resulted in a loss of EV neutralizing activity, but all EV gene knockout viruses still induced a robust neutralizing activity against the vaccinia MV form of the virus. The effect of elimination of A33 and/or B5 on the protection afforded by vaccination was evaluated by intranasal challenge with a lethal dose of either vaccinia virus WR or IHD-J, a strain of vaccinia virus that produces relatively higher amounts of EV virus. The results from multiple experiments, using a range of vaccination doses and virus challenge doses, and using mortality, morbidity, and virus dissemination as endpoints, indicate that the absence of A33 and B5 have little effect on the ability of a vaccinia vaccine virus to provide protection against a lethal intranasal challenge in a mouse model.

Genetic Variability of Myxoma Virus Genomes

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Braun, Christoph; Thürmer, Andrea; Daniel, Rolf; Schultz, Anne-Kathrin; Bulla, Ingo; Schirrmeier, Horst; Mayer, Dietmar; Neubert, Andreas

2016-01-01

ABSTRACT Myxomatosis is a recurrent problem on rabbit farms throughout Europe despite the success of vaccines. To identify gene variations of field and vaccine strains that may be responsible for changes in virulence, immunomodulation, and immunoprotection, the genomes of 6 myxoma virus (MYXV) strains were sequenced: German field isolates Munich-1, FLI-H, 2604, and 3207; vaccine strain MAV; and challenge strain ZA. The analyzed genomes ranged from 147.6 kb (strain MAV) to 161.8 kb (strain 3207). All sequences were affected by several mutations, covering 24 to 93 open reading frames (ORFs) and resulted in amino acid substitutions, insertions, or deletions. Only strains Munich-1 and MAV revealed the deletion of 10 ORFs (M007L to M015L) and 11 ORFs (M007L to M008.1L and M149R to M008.1R), respectively. Major differences were observed in the 27 immunomodulatory proteins encoded by MYXV. Compared to the reference strain Lausanne, strains FLI-H, 2604, 3207, and ZA showed the highest amino acid identity (>98.4%). In strains Munich-1 and MAV, deletion of 5 and 10 ORFs, respectively, was observed, encoding immunomodulatory proteins with ankyrin repeats or members of the family of serine protease inhibitors. Furthermore, putative immunodominant surface proteins with homology to vaccinia virus (VACV) were investigated in the sequenced strains. Only strain MAV revealed above-average frequencies of amino acid substitutions and frameshift mutations. Finally, we performed recombination analysis and found signs of recombination in vaccine strain MAV. Phylogenetic analysis showed a close relationship of strain MAV and the MSW strain of Californian MYXV. However, in a challenge model, strain MAV provided full protection against lethal challenges with strain ZA. IMPORTANCE Myxoma virus (MYXV) is pathogenic for European rabbits and two North American species. Due to sophisticated strategies in immune evasion and oncolysis, MYXV is an important model virus for immunological and

Efficacy of Recombinant Canine Distemper Virus Expressing Leishmania Antigen against Leishmania Challenge in Dogs.

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Ryuichi Miura

Full Text Available Canine distemper virus (CDV vaccination confers long-term protection against CDV reinfection. To investigate the utility of CDV as a polyvalent vaccine vector for Leishmania, we generated recombinant CDVs, based on an avirulent Yanaka strain, that expressed Leishmania antigens: LACK, TSA, or LmSTI1 (rCDV-LACK, rCDV-TSA, and rCDV-LmSTI1, respectively. Dogs immunized with rCDV-LACK were protected against challenge with lethal doses of virulent CDV, in the same way as the parental Yanaka strain. To evaluate the protective effects of the recombinant CDVs against cutaneous leishmaniasis in dogs, dogs were immunized with one recombinant CDV or a cocktail of three recombinant CDVs, before intradermal challenge (in the ears with infective-stage promastigotes of Leishmania major. Unvaccinated dogs showed increased nodules with ulcer formation after 3 weeks, whereas dogs immunized with rCDV-LACK showed markedly smaller nodules without ulceration. Although the rCDV-TSA- and rCDV-LmSTI1-immunized dogs showed little protection against L. major, the cocktail of three recombinant CDVs more effectively suppressed the progression of nodule formation than immunization with rCDV-LACK alone. These results indicate that recombinant CDV is suitable for use as a polyvalent live attenuated vaccine for protection against both CDV and L. major infections in dogs.

B cells are not essential for Lactobacillus-mediated protection against lethal pneumovirus infection*

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Percopo, Caroline M.; Dyer, Kimberly D.; Garcia-Crespo, Katia E.; Gabryszewski, Stanislaw J.; Shaffer, Arthur L.; Domachowske, Joseph B.; Rosenberg, Helene F.

2014-01-01

We have shown previously that priming of respiratory mucosa with live Lactobacillus species promotes robust and prolonged survival from an otherwise lethal infection with pneumonia virus of mice (PVM), a property known as heterologous immunity. Lactobacillus-priming results in a moderate reduction in virus recovery and a dramatic reduction in virus-induced proinflammatory cytokine production; the precise mechanisms underlying these findings remain to be elucidated. As B cells have been shown ...

Vaccination against porcine parvovirus protects against disease, but does not prevent infection and virus shedding after challenge infection with a heterologous virus strain.

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Jóźwik, A; Manteufel, J; Selbitz, H-J; Truyen, U

2009-10-01

The demonstration of field isolates of porcine parvovirus (PPV) that differ genetically and antigenically from vaccine strains of PPV raises the question of whether the broadly used inactivated vaccines can still protect sows against the novel viruses. Ten specific-pathogen-free primiparous sows were assigned to three groups and were vaccinated with one of two vaccines based on the old vaccine strains, or served as non-vaccinated controls. After insemination, all sows were challenged with the prototype genotype 2 virus, PPV-27a, on gestation day 41; fetuses were delivered on gestation day 90 and examined for virus infection. The fetuses of the vaccinated sows were protected against disease, but both the vaccinated and the non-vaccinated sows showed a marked increase in antibody titres after challenge infection, indicating replication of the challenge virus. All sows (vaccinated and non-vaccinated) shed the challenge virus for at least 10 days after infection, with no difference in the pattern or duration of virus shedding.

Vaccination with Recombinant Parainfluenza Virus 5 Expressing Neuraminidase Protects against Homologous and Heterologous Influenza Virus Challenge.

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Mooney, Alaina J; Gabbard, Jon D; Li, Zhuo; Dlugolenski, Daniel A; Johnson, Scott K; Tripp, Ralph A; He, Biao; Tompkins, S Mark

2017-12-01

Seasonal human influenza virus continues to cause morbidity and mortality annually, and highly pathogenic avian influenza (HPAI) viruses along with other emerging influenza viruses continue to pose pandemic threats. Vaccination is considered the most effective measure for controlling influenza; however, current strategies rely on a precise vaccine match with currently circulating virus strains for efficacy, requiring constant surveillance and regular development of matched vaccines. Current vaccines focus on eliciting specific antibody responses against the hemagglutinin (HA) surface glycoprotein; however, the diversity of HAs across species and antigenic drift of circulating strains enable the evasion of virus-inhibiting antibody responses, resulting in vaccine failure. The neuraminidase (NA) surface glycoprotein, while diverse, has a conserved enzymatic site and presents an appealing target for priming broadly effective antibody responses. Here we show that vaccination with parainfluenza virus 5 (PIV5), a promising live viral vector expressing NA from avian (H5N1) or pandemic (H1N1) influenza virus, elicited NA-specific antibody and T cell responses, which conferred protection against homologous and heterologous influenza virus challenges. Vaccination with PIV5-N1 NA provided cross-protection against challenge with a heterosubtypic (H3N2) virus. Experiments using antibody transfer indicate that antibodies to NA have an important role in protection. These findings indicate that PIV5 expressing NA may be effective as a broadly protective vaccine against seasonal influenza and emerging pandemic threats. IMPORTANCE Seasonal influenza viruses cause considerable morbidity and mortality annually, while emerging viruses pose potential pandemic threats. Currently licensed influenza virus vaccines rely on the antigenic match of hemagglutinin (HA) for vaccine strain selection, and most vaccines rely on HA inhibition titers to determine efficacy, despite the growing

The pathogenicity of thymidine kinase-deficient mutants of herpes simplex virus in mice.

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Field, H J; Wildy, P

1978-10-01

The pathogenicity for mice of two mutants of herpes simplex virus (type 1 and type 2), which fail to induce thymidine kinase, were compared with their respective parent strains. The mutants were much less virulent than the parents following either intracerebral or peripheral inoculation. The replication of the virus at the site of inoculation and its progression into the nervous system were studied. Following a very large inoculum in the ear, the type 1 mutant was found to establish a latent infection in the cervical dorsal root ganglia. Mice inoculated intracerebrally with small doses of the mutant viruses were solidly immune to challenge with lethal doses of the parent strain.

Cross-protective peptide vaccine against influenza A viruses developed in HLA-A*2402 human immunity model.

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Toru Ichihashi

Full Text Available BACKGROUND: The virus-specific cytotoxic T lymphocyte (CTL induction is an important target for the development of a broadly protective human influenza vaccine, since most CTL epitopes are found on internal viral proteins and relatively conserved. In this study, the possibility of developing a strain/subtype-independent human influenza vaccine was explored by taking a bioinformatics approach to establish an immunogenic HLA-A24 restricted CTL epitope screening system in HLA-transgenic mice. METHODOLOGY/PRINCIPAL FINDINGS: HLA-A24 restricted CTL epitope peptides derived from internal proteins of the H5N1 highly pathogenic avian influenza A virus were predicted by CTL epitope peptide prediction programs. Of 35 predicted peptides, six peptides exhibited remarkable cytotoxic activity in vivo. More than half of the mice which were subcutaneously vaccinated with the three most immunogenic and highly conserved epitopes among three different influenza A virus subtypes (H1N1, H3N2 and H5N1 survived lethal influenza virus challenge during both effector and memory CTL phases. Furthermore, mice that were intranasally vaccinated with these peptides remained free of clinical signs after lethal virus challenge during the effector phase. CONCLUSIONS/SIGNIFICANCE: This CTL epitope peptide selection system can be used as an effective tool for the development of a cross-protective human influenza vaccine. Furthermore this vaccine strategy can be applicable to the development of all intracellular pathogens vaccines to induce epitope-specific CTL that effectively eliminate infected cells.

Influence of virus strain and antigen mass on efficacy of H5 avian influenza inactivated vaccines.

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Swayne, D E; Beck, J R; Garcia, M; Stone, H D

1999-06-01

The influence of vaccine strain and antigen mass on the ability of inactivated avian influenza (AI) viruses to protect chicks from a lethal, highly pathogenic (HP) AI virus challenge was studied. Groups of 4-week-old chickens were immunized with inactivated vaccines containing one of 10 haemagglutinin subtype H5 AI viruses, one heterologous H7 AI virus or normal allantoic fluid (sham), and challenged 3 weeks later by intra-nasal inoculation with a HP H5 chicken-origin AI virus. All 10 H5 vaccines provided good protection from clinical signs and death, and produced positive serological reactions on agar gel immunodiffusion and haemagglutination inhibition tests. In experiment 1, challenge virus was recovered from the oropharynx of 80% of chickens in the H5 vaccine group. In five H5 vaccine groups, challenge virus was not recovered from the cloaca of chickens. In the other five H5 vaccine groups, the number of chickens with detection of challenge virus from the cloaca was lower than in the sham group (P turkey/Wisconsin/68 (H5N9) was the best vaccine candidate of the H5 strains tested (PD50= 0.006 μg AI antigen). These data demonstrate that chickens vaccinated with inactivated H5 whole virus AI vaccines were protected from clinical signs and death, but usage of vaccine generally did not prevent infection by the challenge virus, as indicated by recovery of virus from the oropharynx. Vaccine use reduced cloacal detection rates, and quantity of virus shed from the cloaca and oropharynx in some vaccine groups, which would potentially reduce environmental contamination and disease transmission in the field.

Efficacy of a parainfluenza virus 5 (PIV5-based H7N9 vaccine in mice and guinea pigs: antibody titer towards HA was not a good indicator for protection.

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Zhuo Li

Full Text Available H7N9 has caused fatal infections in humans. A safe and effective vaccine is the best way to prevent large-scale outbreaks in the human population. Parainfluenza virus 5 (PIV5, an avirulent paramyxovirus, is a promising vaccine vector. In this work, we generated a recombinant PIV5 expressing the HA gene of H7N9 (PIV5-H7 and tested its efficacy against infection with influenza virus A/Anhui/1/2013 (H7N9 in mice and guinea pigs. PIV5-H7 protected the mice against lethal H7N9 challenge. Interestingly, the protection did not require antibody since PIV5-H7 protected JhD mice that do not produce antibody against lethal H7N9 challenge. Furthermore, transfer of anti-H7 serum did not protect mice against H7N9 challenge. PIV5-H7 generated high HAI titers in guinea pigs, however it did not protect against H7N9 infection or transmission. Intriguingly, immunization of guinea pigs with PIV5-H7 and PIV5 expressing NP of influenza A virus H5N1 (PIV5-NP conferred protection against H7N9 infection and transmission. Thus, we have obtained a H7N9 vaccine that protected both mice and guinea pigs against lethal H7N9 challenge and infection respectively.

An orally available, small-molecule polymerase inhibitor shows efficacy against a lethal morbillivirus infection in a large animal model.

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Krumm, Stefanie A; Yan, Dan; Hovingh, Elise S; Evers, Taylor J; Enkirch, Theresa; Reddy, G Prabhakar; Sun, Aiming; Saindane, Manohar T; Arrendale, Richard F; Painter, George; Liotta, Dennis C; Natchus, Michael G; von Messling, Veronika; Plemper, Richard K

2014-04-16

Measles virus is a highly infectious morbillivirus responsible for major morbidity and mortality in unvaccinated humans. The related, zoonotic canine distemper virus (CDV) induces morbillivirus disease in ferrets with 100% lethality. We report an orally available, shelf-stable pan-morbillivirus inhibitor that targets the viral RNA polymerase. Prophylactic oral treatment of ferrets infected intranasally with a lethal CDV dose reduced viremia and prolonged survival. Ferrets infected with the same dose of virus that received post-infection treatment at the onset of viremia showed low-grade viral loads, remained asymptomatic, and recovered from infection, whereas control animals succumbed to the disease. Animals that recovered also mounted a robust immune response and were protected against rechallenge with a lethal CDV dose. Drug-resistant viral recombinants were generated and found to be attenuated and transmission-impaired compared to the genetic parent virus. These findings may pioneer a path toward an effective morbillivirus therapy that could aid measles eradication by synergizing with vaccination to close gaps in herd immunity due to vaccine refusal.

Canine parvovirus type 2 vaccine protects against virulent challenge with type 2c virus.

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Spibey, N; Greenwood, N M; Sutton, D; Chalmers, W S K; Tarpey, I

2008-04-01

The ability of dogs vaccinated with a live attenuated CPV type 2 (Nobivac Intervet) vaccine to resist challenge with a current CPV2c isolate was investigated. Six SPF beagle dogs were given the minimum recommended course of vaccination, comprising a single inoculation of vaccine (Nobivac Lepto+Nobivac Pi) at 8-10 weeks of age followed 3 weeks later with a parvovirus vaccine in combination with distemper, adenovirus and parainfluenza virus (Nobivac DHPPi) and a repeat leptospirosis vaccine. Six control dogs were kept unvaccinated. All animals were challenged orally with a type 2c isolate of CPV and monitored for clinical signs, virus shedding, white blood cell fluctuations and serological responses. All vaccinated dogs were fully protected; showing no clinical signs nor shedding challenge virus in the faeces, in contrast to control animals, which displayed all the typical signs of infection with pathogenic CPV and shed challenge virus in the faeces.

Evaluation of synthetic infection-enhancing lipopeptides as adjuvants for a live-attenuated canine distemper virus vaccine administered intra-nasally to ferrets.

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Nguyen, D Tien; Ludlow, Martin; van Amerongen, Geert; de Vries, Rory D; Yüksel, Selma; Verburgh, R Joyce; Osterhaus, Albert D M E; Duprex, W Paul; de Swart, Rik L

2012-07-20

Inactivated paramyxovirus vaccines have been associated with hypersensitivity responses upon challenge infection. For measles and canine distemper virus (CDV) safe and effective live-attenuated virus vaccines are available, but for human respiratory syncytial virus and human metapneumovirus development of such vaccines has proven difficult. We recently identified three synthetic bacterial lipopeptides that enhance paramyxovirus infections in vitro, and hypothesized these could be used as adjuvants to promote immune responses induced by live-attenuated paramyxovirus vaccines. Here, we tested this hypothesis using a CDV vaccination and challenge model in ferrets. Three groups of six animals were intra-nasally vaccinated with recombinant (r) CDV(5804P)L(CCEGFPC) in the presence or absence of the infection-enhancing lipopeptides Pam3CSK4 or PHCSK4. The recombinant CDV vaccine virus had previously been described to be over-attenuated in ferrets. A group of six animals was mock-vaccinated as control. Six weeks after vaccination all animals were challenged with a lethal dose of rCDV strain Snyder-Hill expressing the red fluorescent protein dTomato. Unexpectedly, intra-nasal vaccination of ferrets with rCDV(5804P)L(CCEGFPC) in the absence of lipopeptides resulted in good immune responses and protection against lethal challenge infection. However, in animals vaccinated with lipopeptide-adjuvanted virus significantly higher vaccine virus loads were detected in nasopharyngeal lavages and peripheral blood mononuclear cells. In addition, these animals developed significantly higher CDV neutralizing antibody titers compared to animals vaccinated with non-adjuvanted vaccine. This study demonstrates that the synthetic cationic lipopeptides Pam3CSK4 and PHCSK4 not only enhance paramyxovirus infection in vitro, but also in vivo. Given the observed enhancement of immunogenicity their potential as adjuvants for other live-attenuated paramyxovirus vaccines should be considered

Rapid Engineering of Foot-and-Mouth Disease Vaccine and Challenge Viruses.

Science.gov (United States)

Lee, Seo-Yong; Lee, Yeo-Joo; Kim, Rae-Hyung; Park, Jeong-Nam; Park, Min-Eun; Ko, Mi-Kyeong; Choi, Joo-Hyung; Chu, Jia-Qi; Lee, Kwang-Nyeong; Kim, Su-Mi; Tark, Dongseob; Lee, Hyang-Sim; Ko, Young-Joon; Seo, Min-Goo; Park, Jung-Won; Kim, Byounghan; Lee, Myoung-Heon; Lee, Jong-Soo; Park, Jong-Hyeon

2017-08-15

There are seven antigenically distinct serotypes of foot-and-mouth disease virus (FMDV), each of which has intratypic variants. In the present study, we have developed methods to efficiently generate promising vaccines against seven serotypes or subtypes. The capsid-encoding gene (P1) of the vaccine strain O1/Manisa/Turkey/69 was replaced with the amplified or synthetic genes from the O, A, Asia1, C, SAT1, SAT2, and SAT3 serotypes. Viruses of the seven serotype were rescued successfully. Each chimeric FMDV with a replacement of P1 showed serotype-specific antigenicity and varied in terms of pathogenesis in pigs and mice. Vaccination of pigs with an experimental trivalent vaccine containing the inactivated recombinants based on the main serotypes O, A, and Asia1 effectively protected them from virus challenge. This technology could be a potential strategy for a customized vaccine with challenge tools to protect against epizootic disease caused by specific serotypes or subtypes of FMDV. IMPORTANCE Foot-and-mouth disease (FMD) virus (FMDV) causes significant economic losses. For vaccine preparation, the selection of vaccine strains was complicated by high antigenic variation. In the present study, we suggested an effective strategy to rapidly prepare and evaluate mass-produced customized vaccines against epidemic strains. The P1 gene encoding the structural proteins of the well-known vaccine virus was replaced by the synthetic or amplified genes of viruses of seven representative serotypes. These chimeric viruses generally replicated readily in cell culture and had a particle size similar to that of the original vaccine strain. Their antigenicity mirrored that of the original serotype from which their P1 gene was derived. Animal infection experiments revealed that the recombinants varied in terms of pathogenicity. This strategy will be a useful tool for rapidly generating customized FMD vaccines or challenge viruses for all serotypes, especially for FMD-free countries

MP-12 virus containing the clone 13 deletion in the NSs gene prevents lethal disease when administered after Rift Valley fever virus infection in hamsters.

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Gowen, Brian B; Westover, Jonna B; Sefing, Eric J; Bailey, Kevin W; Nishiyama, Shoko; Wandersee, Luci; Scharton, Dionna; Jung, Kie-Hoon; Ikegami, Tetsuro

2015-01-01

Rift Valley fever virus (RVFV; Bunyaviridae, Phlebovirus) causes a range of illnesses that include retinitis, fulminant hepatitis, neurologic disease, and hemorrhagic fever. In hospitalized individuals, case fatality rates can be as high as 10-20%. There are no vaccines or antivirals approved for human use to prevent or treat severe RVFV infections. We previously tested the efficacy of the MP-12 vaccine strain and related variants with NSs truncations as a post-exposure prophylaxis in mice infected with wild-type pathogenic RVFV strain ZH501. Post-exposure efficacy of the rMP12-C13type, a recombinant MP-12 vaccine virus which encodes an in-frame truncation removing 69% of the NSs protein, resulted in 30% survival when administering the virus within 30 min of subcutaneous ZH501 challenge in mice, while the parental MP-12 virus conferred no protection by post-exposure vaccination. Here, we demonstrate uniform protection of hamsters by post-exposure vaccination with rMP12-C13type administered 6 h post-ZH501 infection while no efficacy was observed with the parental MP-12 virus. Notably, both the MP-12 and rMP12-C13type viruses were highly effective (100% protection) when administered 21 days prior to challenge. In a subsequent study delaying vaccination until 8, 12, and 24 h post-RVFV exposure, we observed 80, 70, and 30% survival, respectively. Our findings indicate that the rapid protective innate immune response elicited by rMP12-C13type may be due to the truncated NSs protein, suggesting that the resulting functional inactivation of NSs plays an important role in the observed post-exposure efficacy. Taken together, the data demonstrate that post-exposure vaccination with rMP12-C13type is effective in limiting ZH501 replication and associated disease in standard pre-exposure vaccination and post-challenge treatment models of RVFV infection, and suggest an extended post-exposure prophylaxis window beyond that initially observed in mice.

DNA vaccines encoding proteins from wild-type and attenuated canine distemper virus protect equally well against wild-type virus challenge.

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Nielsen, Line; Jensen, Trine Hammer; Kristensen, Birte; Jensen, Tove Dannemann; Karlskov-Mortensen, Peter; Lund, Morten; Aasted, Bent; Blixenkrone-Møller, Merete

2012-10-01

Immunity induced by DNA vaccines containing the hemagglutinin (H) and nucleoprotein (N) genes of wild-type and attenuated canine distemper virus (CDV) was investigated in mink (Mustela vison), a highly susceptible natural host of CDV. All DNA-immunized mink seroconverted, and significant levels of virus-neutralizing (VN) antibodies were present on the day of challenge with wild-type CDV. The DNA vaccines also primed the cell-mediated memory responses, as indicated by an early increase in the number of interferon-gamma (IFN-γ)-producing lymphocytes after challenge. Importantly, the wild-type and attenuated CDV DNA vaccines had a long-term protective effect against wild-type CDV challenge. The vaccine-induced immunity induced by the H and N genes from wild-type CDV and those from attenuated CDV was comparable. Because these two DNA vaccines were shown to protect equally well against wild-type virus challenge, it is suggested that the genetic/antigenic heterogeneity between vaccine strains and contemporary wild-type strains are unlikely to cause vaccine failure.

The efficacy and pharmacokinetics of brincidofovir for the treatment of lethal rabbitpox virus infection: a model of smallpox disease.

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Trost, Lawrence C; Rose, Michelle L; Khouri, Jody; Keilholz, Laurie; Long, James; Godin, Stephen J; Foster, Scott A

2015-05-01

Brincidofovir (BCV) has broad-spectrum in vitro activity against dsDNA viruses, including smallpox, and is being developed as a treatment for smallpox as well as infections caused by other dsDNA viruses. BCV has previously been shown to be active in multiple animal models of smallpox. Here we present the results of a randomized, blinded, placebo-controlled study of the efficacy and pharmacokinetics of a novel, "humanized" regimen of BCV for treatment of New Zealand White rabbits infected with a highly lethal inoculum of rabbitpox virus, a well characterized model of smallpox. Compared with placebo, a dose-dependent increase in survival was observed in all BCV-treatment groups. Concentrations of cidofovir diphosphate (CDV-PP), the active antiviral, in rabbit peripheral blood mononuclear cells (PBMCs) were determined for comparison to those produced in humans at the dose proposed for treatment of smallpox. CDV-PP exposure in PBMCs from rabbits given BCV scaled to human exposures at the dose proposed for treatment of smallpox, which is also currently under evaluation for other indications. The results of this study demonstrate the activity of BCV in the rabbitpox model of smallpox and the feasibility of scaling doses efficacious in the model to a proposed human dose and regimen for treatment of smallpox. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Smallpox virus plaque phenotypes: genetic, geographical and case fatality relationships.

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Olson, Victoria A; Karem, Kevin L; Smith, Scott K; Hughes, Christine M; Damon, Inger K

2009-04-01

Smallpox (infection with Orthopoxvirus variola) remains a feared illness more than 25 years after its eradication. Historically, case-fatality rates (CFRs) varied between outbreaks (<1 to approximately 40 %), the reasons for which are incompletely understood. The extracellular enveloped virus (EEV) form of orthopoxvirus progeny is hypothesized to disseminate infection. Investigations with the closely related Orthopoxvirus vaccinia have associated increased comet formation (EEV production) with increased mouse mortality (pathogenicity). Other vaccinia virus genetic manipulations which affect EEV production inconsistently support this association. However, antisera against vaccinia virus envelope protect mice from lethal challenge, further supporting a critical role for EEV in pathogenicity. Here, we show that the increased comet formation phenotypes of a diverse collection of variola viruses associate with strain phylogeny and geographical origin, but not with increased outbreak-related CFRs; within clades, there may be an association of plaque size with CFR. The mechanisms for variola virus pathogenicity probably involves multiple host and pathogen factors.

Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model.

Science.gov (United States)

Carlson, Jolene; O'Donnell, Vivian; Alfano, Marialexia; Velazquez Salinas, Lauro; Holinka, Lauren G; Krug, Peter W; Gladue, Douglas P; Higgs, Stephen; Borca, Manuel V

2016-10-22

African swine fever (ASF) is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV). There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4) virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus) is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi) showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi). This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN)-γ responses, or specific cytokine profiles) and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms.

Long-term protective immunity from an influenza virus-like particle vaccine administered with a microneedle patch.

Science.gov (United States)

Quan, Fu-Shi; Kim, Yeu-Chun; Song, Jae-Min; Hwang, Hye Suk; Compans, Richard W; Prausnitz, Mark R; Kang, Sang-Moo

2013-09-01

Skin vaccination with influenza virus-like particles (VLPs) using microneedles has been shown to induce protection similar to or better than that induced by intramuscular immunization. In this study, we examined the long-term protective efficacy of influenza (H1N1 A/PR/8/34) VLPs after skin vaccination using microneedle patches coated with the vaccine. Microneedle vaccination of mice in the skin induced 100% protection against lethal challenge infection with influenza A/PR/8/34 virus 14 months after a single vaccine dose. Influenza virus-specific total IgG response and hemagglutination inhibition (HAI) titers were maintained at high levels for over 1 year after microneedle vaccination. Microneedle vaccination also induced substantial levels of lung IgG and IgA antibody responses, and antibody-secreting plasma cells from spleen and bone marrow, as well as conferring effective control of lung viral loads, resulting in complete protection 14 months after vaccination. These strong and long-lasting immune responses were enabled in part by stabilization of the vaccine by formulation with trehalose during microneedle patch fabrication. Administration of the stabilized vaccine using microneedles was especially effective at enabling strong recall responses measured 4 days after lethal virus challenge, including increased HAI and antibody-secreting cells in the spleen and reduced viral titer and inflammatory response in the lung. The results in this study indicate that skin vaccination with VLP vaccine using a microneedle patch provides long-term protection against influenza in mice.

Exposure to a low pathogenic A/H7N2 virus in chickens protects against highly pathogenic A/H7N1 virus but not against subsequent infection with A/H5N1.

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Júlia Vergara-Alert

Full Text Available Recent evidences have demonstrated that the presence of low pathogenic avian influenza viruses (LPAIV may play an important role in host ecology and transmission of avian influenza viruses (AIV. While some authors have clearly demonstrated that LPAIV can mutate to render highly pathogenic avian influenza viruses (HPAIV, others have shown that their presence could provide the host with enough immunological memory to resist re-infections with HPAIV. In order to experimentally study the role of pre-existing host immunity, chickens previously infected with H7N2 LPAIV were subsequently challenged with H7N1 HPAIV. Pre-infection of chickens with H7N2 LAPIV conferred protection against the lethal challenge with H7N1 HPAIV, dramatically reducing the viral shedding, the clinical signs and the pathological outcome. Correlating with the protection afforded, sera from chickens primed with H7N2 LPAIV reacted with the H7-AIV subtype in hemagglutination inhibition assay and specifically with the N2-neuraminidase antigen. Conversely, subsequent exposure to H5N1 HPAIV resulted in a two days-delay on the onset of disease but all chickens died by 7 days post-challenge. Lack of protection correlated with the absence of H5-hemagglutining inhibitory antibodies prior to H5N1 HPAIV challenge. Our data suggest that in naturally occurring outbreaks of HPAIV, birds with pre-existing immunity to LPAIV could survive lethal infections with HA-homologous HPAIV but not subsequent re-infections with HA-heterologous HPAIV. These results could be useful to better understand the dynamics of AIV in chickens and might help in future vaccine formulations.

Crop immunity against viruses: outcomes and future challenges

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Valerie eNicaise

2014-11-01

Full Text Available Viruses cause epidemics on all major cultures of agronomic importance, representing a serious threat to global food security. As strict intracellular pathogens, they cannot be controlled chemically and prophylactic measures consist mainly in the destruction of infected plants and excessive pesticide applications to limit the population of vector organisms. A powerful alternative frequently employed in agriculture relies on the use of crop genetic resistances, approach that depends on mechanisms governing plant-virus interactions. Hence, knowledge related to the molecular bases of viral infections and crop resistances is key to face viral attacks in fields. Over the past 80 years, great advances have been made on our understanding of plant immunity against viruses. Although most of the known natural resistance genes have long been dominant R genes (encoding NBS-LRR proteins, a vast number of crop recessive resistance genes were cloned in the last decade, emphasizing another evolutive strategy to block viruses. In addition, the discovery of RNA interference pathways highlighted a very efficient antiviral system targeting the infectious agent at the nucleic acid level. Insidiously, plant viruses evolve and often acquire the ability to overcome the resistances employed by breeders. The development of efficient and durable resistances able to withstand the extreme genetic plasticity of viruses therefore represents a major challenge for the coming years. This review aims at describing some of the most devastating diseases caused by viruses on crops and summarizes current knowledge about plant-virus interactions, focusing on resistance mechanisms that prevent or limit viral infection in plants. In addition, I will discuss the current outcomes of the actions employed to control viral diseases in fields and the future investigations that need to be undertaken to develop sustainable broad-spectrum crop resistances against viruses.

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

DEFF Research Database (Denmark)

Andersen, C; Jensen, T; Nansen, A

1999-01-01

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

A single cidofovir treatment rescues animals at progressive stages of lethal orthopoxvirus disease

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Israely Tomer

2012-06-01

Full Text Available Abstract Background In an event of a smallpox outbreak in humans, the window for efficacious treatment by vaccination with vaccinia viruses (VACV is believed to be limited to the first few days post-exposure (p.e.. We recently demonstrated in a mouse model for human smallpox, that active immunization 2–3 days p.e. with either VACV-Lister or modified VACV Ankara (MVA vaccines, can rescue animals from lethal challenge of ectromelia virus (ECTV, the causative agent of mousepox. The present study was carried out in order to determine whether a single dose of the anti-viral cidofovir (CDV, administered at different times and doses p.e. either alone or in conjunction with active vaccination, can rescue ECTV infected mice. Methods Animals were infected intranasally with ECTV, treated on different days with various single CDV doses and monitored for morbidity, mortality and humoral response. In addition, in order to determine the influence of CDV on the immune response following vaccination, both the "clinical take”, IFN-gamma and IgG Ab levels in the serum were evaluated as well as the ability of the mice to withstand a lethal challenge of ECTV. Finally the efficacy of a combined treatment regime of CDV and vaccination p.e. was determined. Results A single p.e. CDV treatment is sufficient for protection depending on the initiation time and dose (2.5 – 100 mg/kg of treatment. Solid protection was achieved by a low dose (5 mg/kg CDV treatment even if given at day 6 p.e., approximately 4 days before death of the control infected untreated mice (mean time to death (MTTD 10.2. At the same time point complete protection was achieved by single treatment with higher doses of CDV (25 or 100 mg/kg. Irrespective of treatment dose, all surviving animals developed a protective immune response even when the CDV treatment was initiated one day p.e.. After seven days post treatment with the highest dose (100 mg/kg, virus was still detected in some

Severe virus associated community acquired pneumonia: predictors of lethality

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T. O. Pertseva

2016-06-01

Full Text Available Despite the fact that the influenza virus pathogenicity factors have been well studied in vitro, in vivo lack is presented in understanding of the those risk factors, objective and laboratory parameters, which related most of all to the fatal virus-associated community-aquired pneumonia (CAP. That is why the purpose of the study was to study the clinical and laboratory characteristics of patients with severe virus-associated CAP during the 2015–2016 influenza epidemic and their role as predictors of patients’ mortality. To do this, patients with severe virus-associated CAP were examined. They were divided into 2 groups depending on the outcome of treatment: 1st- deaths from the virus-associated severe CAP and 2nd - patients with successful treatment of the severe virus-associated CAP. Special statistical method was used – one-dimensional analysis of variance to compare individual parameters between the two groups of patients (surviving and deceased. Pearson χ2 test (contingency table was used for categorical variables. Factors that were significant predictors of mortality as a result of univariate analysis were tested using multifactorial analysis using logistic regression. In the final model, each parameter must have had a significant impact on mortality. It was found that risk factors for death in patients with severe virus-associated CAP according to univariate analysis were: presence of obesity, disorders of consciousness, BH≥35 min, SaO2<80%, PaO2<50 mm Hg, mmHg PaCO2 ≥50 mmHg during hospitalization. Independent predictors of mortality according to the logistic regression are the presence of obesity, disorders of consciousness, PaO2<50 mm Hg, mmHg PaCO2 ≥50 mmHg. Given that among clinical and laboratory parameters key parameters that significantly influence the outcome, are indicators of the severity of hypoxia and hypoxemia, a major step in determining the severity of the patients with virus-associated severe emergency is

Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model

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Jolene Carlson

2016-10-01

Full Text Available African swine fever (ASF is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV. There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4 virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi. This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN-γ responses, or specific cytokine profiles and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms.

An avirulent chimeric Pestivirus with altered cell tropism protects pigs against lethal infection with classical swine fever virus

International Nuclear Information System (INIS)

Reimann, Ilona; Depner, Klaus; Trapp, Sascha; Beer, Martin

2004-01-01

A chimeric Pestivirus was constructed using an infectious cDNA clone of bovine viral diarrhea virus (BVDV) [J. Virol. 70 (1996) 8606]. After deletion of the envelope protein E2-encoding region, the respective sequence of classical swine fever virus (CSFV) strain Alfort 187 was inserted in-frame resulting in plasmid pA/CP7 E 2alf. After transfection of in vitro-transcribed CP7 E 2alf RNA, autonomous replication of chimeric RNA in bovine and porcine cell cultures was observed. Efficient growth of chimeric CP7 E 2alf virus, however, could only be demonstrated on porcine cells, and in contrast to the parental BVDV strain CP7, CP7 E 2alf only inefficiently infected and propagated in bovine cells. The virulence, immunogenicity, and 'marker vaccine' properties of the generated chimeric CP7 E 2alf virus were determined in an animal experiment using 27 pigs. After intramuscular inoculation of 1 x 10 7 TCID 50 , CP7 E 2alf proved to be completely avirulent, and neither viremia nor virus transmission to contact animals was observed; however, CSFV-specific neutralizing antibodies were detected from day 11 after inoculation. In addition, sera from all animals reacted positive in an E2-specific CSFV-antibody ELISA, but were negative for CSFV-E RNS -specific antibodies as determined with a CSFV marker ELISA. After challenge infection with highly virulent CSFV strain Eystrup, pigs immunized with CP7 E 2alf were fully protected against clinical signs of CSFV infection, viremia, and shedding of challenge virus, and almost all animals scored positive in a CSFV marker ELISA. From our results, we conclude that chimeric CP7 E 2alf may not only serve as a tool for a better understanding of Pestivirus attachment, entry, and assembly, but also represents an innocuous and efficacious modified live CSFV 'marker vaccine'

Chitosan can stop or postpone the death of the suckling mice challenged with foot-and-mouth disease virus

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Li Dong

2010-06-01

Full Text Available Abstract In the study, a method called "hardening in liquid phase" for preparing chitosan granules with glutaraldehyde as crosslinker and Tween 80 as surfactant and paraffin liquid as dispersant was established. The chitosan granules were light yellow and insoluble in water or oil, but they swelled in acid solution and narrowed in neutral or alkaline solution. Furthermore, some of characteristics of the chitosan granules were revealed. (a Stability: Their shapes were stable at pH 7.0 and pH 8.0 and -30°C~120°C. The shelf life is at least one year in vitro at room temperature. (b Safety: Some experiments of their lethal effect to suckling mice and pathogenicity to mature mice proved the chitosan granules were harmless. (c Antiviral activity: Some suckling mice injected with chitosan granules were still alive or delayed death compared with control group when they challenged with foot-and-mouth disease virus (FMDV. Such anti-FMDV capacity could maintain 1 week and was the strongest on the third day.

Reassortant H1N1 influenza virus vaccines protect pigs against pandemic H1N1 influenza virus and H1N2 swine influenza virus challenge.

Science.gov (United States)

Yang, Huanliang; Chen, Yan; Shi, Jianzhong; Guo, Jing; Xin, Xiaoguang; Zhang, Jian; Wang, Dayan; Shu, Yuelong; Qiao, Chuanling; Chen, Hualan

2011-09-28

Influenza A (H1N1) virus has caused human influenza outbreaks in a worldwide pandemic since April 2009. Pigs have been found to be susceptible to this influenza virus under experimental and natural conditions, raising concern about their potential role in the pandemic spread of the virus. In this study, we generated a high-growth reassortant virus (SC/PR8) that contains the hemagglutinin (HA) and neuraminidase (NA) genes from a novel H1N1 isolate, A/Sichuan/1/2009 (SC/09), and six internal genes from A/Puerto Rico/8/34 (PR8) virus, by genetic reassortment. The immunogenicity and protective efficacy of this reassortant virus were evaluated at different doses in a challenge model using a homologous SC/09 or heterologous A/Swine/Guangdong/1/06(H1N2) virus (GD/06). Two doses of SC/PR8 virus vaccine elicited high-titer serum hemagglutination inhibiting (HI) antibodies specific for the 2009 H1N1 virus and conferred complete protection against challenge with either SC/09 or GD/06 virus, with reduced lung lesions and viral shedding in vaccine-inoculated animals compared with non-vaccinated control animals. These results indicated for the first time that a high-growth SC/PR8 reassortant H1N1 virus exhibits properties that are desirable to be a promising vaccine candidate for use in swine in the event of a pandemic H1N1 influenza. Copyright © 2011 Elsevier B.V. All rights reserved.

Lethal mutagenesis: targeting the mutator phenotype in cancer.

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Fox, Edward J; Loeb, Lawrence A

2010-10-01

The evolution of cancer and RNA viruses share many similarities. Both exploit high levels of genotypic diversity to enable extensive phenotypic plasticity and thereby facilitate rapid adaptation. In order to accumulate large numbers of mutations, we have proposed that cancers express a mutator phenotype. Similar to cancer cells, many viral populations, by replicating their genomes with low fidelity, carry a substantial mutational load. As high levels of mutation are potentially deleterious, the viral mutation frequency is thresholded at a level below which viral populations equilibrate in a traditional mutation-selection balance, and above which the population is no longer viable, i.e., the population undergoes an error catastrophe. Because their mutation frequencies are fine-tuned just below this error threshold, viral populations are susceptible to further increases in mutational load and, recently this phenomenon has been exploited therapeutically by a concept that has been termed lethal mutagenesis. Here we review the application of lethal mutagenesis to the treatment of HIV and discuss how lethal mutagenesis may represent a novel therapeutic approach for the treatment of solid cancers. Copyright © 2010 Elsevier Ltd. All rights reserved.

Therapeutic efficacy of antibodies lacking Fcγ receptor binding against lethal dengue virus infection is due to neutralizing potency and blocking of enhancing antibodies [corrected].

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Katherine L Williams

2013-02-01

Full Text Available Dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS are life-threatening complications following infection with one of the four serotypes of dengue virus (DENV. At present, no vaccine or antiviral therapies are available against dengue. Here, we characterized a panel of eight human or mouse-human chimeric monoclonal antibodies (MAbs and their modified variants lacking effector function and dissected the mechanism by which some protect against antibody-enhanced lethal DENV infection. We found that neutralizing modified MAbs that recognize the fusion loop or the A strand epitopes on domains II and III of the envelope protein, respectively, act therapeutically by competing with and/or displacing enhancing antibodies. By analyzing these relationships, we developed a novel in vitro suppression-of-enhancement assay that predicts the ability of modified MAbs to act therapeutically against antibody-enhanced disease in vivo. These studies provide new insight into the biology of DENV pathogenesis and the requirements for antibodies to treat lethal DENV disease.

Venezuelan equine encephalitis virus replicon particle vaccine protects nonhuman primates from intramuscular and aerosol challenge with ebolavirus.

Science.gov (United States)

Herbert, Andrew S; Kuehne, Ana I; Barth, James F; Ortiz, Ramon A; Nichols, Donald K; Zak, Samantha E; Stonier, Spencer W; Muhammad, Majidat A; Bakken, Russell R; Prugar, Laura I; Olinger, Gene G; Groebner, Jennifer L; Lee, John S; Pratt, William D; Custer, Max; Kamrud, Kurt I; Smith, Jonathan F; Hart, Mary Kate; Dye, John M

2013-05-01

There are no vaccines or therapeutics currently approved for the prevention or treatment of ebolavirus infection. Previously, a replicon vaccine based on Venezuelan equine encephalitis virus (VEEV) demonstrated protective efficacy against Marburg virus in nonhuman primates. Here, we report the protective efficacy of Sudan virus (SUDV)- and Ebola virus (EBOV)-specific VEEV replicon particle (VRP) vaccines in nonhuman primates. VRP vaccines were developed to express the glycoprotein (GP) of either SUDV or EBOV. A single intramuscular vaccination of cynomolgus macaques with VRP expressing SUDV GP provided complete protection against intramuscular challenge with SUDV. Vaccination against SUDV and subsequent survival of SUDV challenge did not fully protect cynomolgus macaques against intramuscular EBOV back-challenge. However, a single simultaneous intramuscular vaccination with VRP expressing SUDV GP combined with VRP expressing EBOV GP did provide complete protection against intramuscular challenge with either SUDV or EBOV in cynomolgus macaques. Finally, intramuscular vaccination with VRP expressing SUDV GP completely protected cynomolgus macaques when challenged with aerosolized SUDV, although complete protection against aerosol challenge required two vaccinations with this vaccine.

Mouse dendritic cells pulsed with capsular polysaccharide induce resistance to lethal pneumococcal challenge: roles of T cells and B cells.

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Noam Cohen

Full Text Available Mice are exceedingly sensitive to intra-peritoneal (IP challenge with some virulent pneumococci (LD50 = 1 bacterium. To investigate how peripheral contact with bacterial capsular polysaccharide (PS antigen can induce resistance, we pulsed bone marrow dendritic cells (BMDC of C57BL/6 mice with type 4 or type 3 PS, injected the BMDC intra-foot pad (IFP and challenged the mice IP with supra-lethal doses of pneumococci. We examined the responses of T cells and B cells in the draining popliteal lymph node and measured the effects on the bacteria in the peritoneum and blood. We now report that: 1 The PS co-localized with MHC molecules on the BMDC surface; 2 PS-specific T and B cell proliferation and IFNγ secretion was detected in the draining popliteal lymph nodes on day 4; 3 Type-specific resistance to lethal IP challenge was manifested only after day 5; 4 Type-specific IgM and IgG antibodies were detected in the sera of only some of the mice, but B cells were essential for resistance; 5 Control mice vaccinated with a single injection of soluble PS did not develop a response in the draining popliteal lymph node and were not protected; 6 Mice injected with unpulsed BMDC also did not resist challenge: In unprotected mice, pneumococci entered the blood shortly after IP inoculation and multiplied exponentially in both blood and peritoneum killing the mice within 20 hours. Mice vaccinated with PS-pulsed BMDC trapped the bacteria in the peritoneum. The trapped bacteria proliferated exponentially IP, but died suddenly at 18-20 hours. Thus, a single injection of PS antigen associated with intact BMDC is a more effective vaccine than the soluble PS alone. This model system provides a platform for studying novel aspects of PS-targeted vaccination.

A novel monoclonal antibody effective against lethal challenge with swine-lineage and 2009 pandemic H1N1 influenza viruses in mice

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The HA protein of the 2009 pandemic H1N1viruses (14 H1N1pdm) is antigenically closely related to the HA of classical North American swine H1N1 influenza viruses (cH1N1). Since 1998, through reassortment and incorporation of HA genes from human H3N2 and H1N1 influenza viruses, swine influenza strains...

Preclinical assessment of HIV vaccines and microbicides by repeated low-dose virus challenges.

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Roland R Regoes

2005-08-01

Full Text Available Trials in macaque models play an essential role in the evaluation of biomedical interventions that aim to prevent HIV infection, such as vaccines, microbicides, and systemic chemoprophylaxis. These trials are usually conducted with very high virus challenge doses that result in infection with certainty. However, these high challenge doses do not realistically reflect the low probability of HIV transmission in humans, and thus may rule out preventive interventions that could protect against "real life" exposures. The belief that experiments involving realistically low challenge doses require large numbers of animals has so far prevented the development of alternatives to using high challenge doses.Using statistical power analysis, we investigate how many animals would be needed to conduct preclinical trials using low virus challenge doses. We show that experimental designs in which animals are repeatedly challenged with low doses do not require unfeasibly large numbers of animals to assess vaccine or microbicide success.Preclinical trials using repeated low-dose challenges represent a promising alternative approach to identify potential preventive interventions.

Vaccination against Louping Ill Virus Protects Goats from Experimental Challenge with Spanish Goat Encephalitis Virus.

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Salinas, L M; Casais, R; García Marín, J F; Dalton, K P; Royo, L J; Del Cerro, A; Gayo, E; Dagleish, M P; Alberdi, P; Juste, R A; de la Fuente, J; Balseiro, A

2017-05-01

Spanish goat encephalitis virus (SGEV) is a recently described member of the genus Flavivirus belonging to the tick-borne encephalitis group of viruses, and is closely related to louping ill virus (LIV). Naturally acquired disease in goats results in severe, acute encephalitis and 100% mortality. Eighteen goats were challenged subcutaneously with SGEV; nine were vaccinated previously against LIV and nine were not. None of the vaccinated goats showed any clinical signs of disease or histological lesions, but all of the non-vaccinated goats developed pyrexia and 5/9 developed neurological clinical signs, primarily tremors in the neck and ataxia. All non-vaccinated animals developed histological lesions restricted to the central nervous system and consistent with a lymphocytic meningomyeloencephalitis. Vaccinated goats had significantly (P goats throughout the experiment, but increased rapidly and were significantly (P goats against LIV confers highly effective protection against SGEV; this is probably mediated by IgG and prevents an increase in viral RNA load in serum such that vaccinated animals would not be an effective reservoir of the virus. Copyright © 2017 Elsevier Ltd. All rights reserved.

A neutralizing human monoclonal antibody protects against lethal disease in a new ferret model of acute nipah virus infection.

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Katharine N Bossart

2009-10-01

Full Text Available Nipah virus is a broadly tropic and highly pathogenic zoonotic paramyxovirus in the genus Henipavirus whose natural reservoirs are several species of Pteropus fruit bats. Nipah virus has repeatedly caused outbreaks over the past decade associated with a severe and often fatal disease in humans and animals. Here, a new ferret model of Nipah virus pathogenesis is described where both respiratory and neurological disease are present in infected animals. Severe disease occurs with viral doses as low as 500 TCID(50 within 6 to 10 days following infection. The underlying pathology seen in the ferret closely resembles that seen in Nipah virus infected humans, characterized as a widespread multisystemic vasculitis, with virus replicating in highly vascular tissues including lung, spleen and brain, with recoverable virus from a variety of tissues. Using this ferret model a cross-reactive neutralizing human monoclonal antibody, m102.4, targeting the henipavirus G glycoprotein was evaluated in vivo as a potential therapeutic agent. All ferrets that received m102.4 ten hours following a high dose oral-nasal Nipah virus challenge were protected from disease while all controls died. This study is the first successful post-exposure passive antibody therapy for Nipah virus using a human monoclonal antibody.

Circulating microRNAs in serum from cattle challenged with Bovine Viral Diarrhea Virus

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Bovine viral diarrhea virus (BVDV) is an RNA virus that is often associated with respiratory disease in cattle. MicroRNAs have been proposed as indicators of exposure to respiratory pathogens. The objective of this study was to identify microRNAs in cattle that had been challenged with a non-cytopat...

Possibility and Challenges of Conversion of Current Virus Species Names to Linnaean Binomials

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Postler, Thomas S.; Clawson, Anna N.; Amarasinghe, Gaya K.; Basler, Christopher F.; Bavari, Sbina; Benkő, Mária; Blasdell, Kim R.; Briese, Thomas; Buchmeier, Michael J.; Bukreyev, Alexander; Calisher, Charles H.; Chandran, Kartik; Charrel, Rémi; Clegg, Christopher S.; Collins, Peter L.; Juan Carlos, De La Torre; Derisi, Joseph L.; Dietzgen, Ralf G.; Dolnik, Olga; Dürrwald, Ralf; Dye, John M.; Easton, Andrew J.; Emonet, Sébastian; Formenty, Pierre; Fouchier, Ron A. M.; Ghedin, Elodie; Gonzalez, Jean-Paul; Harrach, Balázs; Hewson, Roger; Horie, Masayuki; Jiāng, Dàohóng; Kobinger, Gary; Kondo, Hideki; Kropinski, Andrew M.; Krupovic, Mart; Kurath, Gael; Lamb, Robert A.; Leroy, Eric M.; Lukashevich, Igor S.; Maisner, Andrea; Mushegian, Arcady R.; Netesov, Sergey V.; Nowotny, Norbert; Patterson, Jean L.; Payne, Susan L.; PaWeska, Janusz T.; Peters, Clarence J.; Radoshitzky, Sheli R.; Rima, Bertus K.; Romanowski, Victor; Rubbenstroth, Dennis; Sabanadzovic, Sead; Sanfaçon, Hélène; Salvato, Maria S.; Schwemmle, Martin; Smither, Sophie J.; Stenglein, Mark D.; Stone, David M.; Takada, Ayato; Tesh, Robert B.; Tomonaga, Keizo; Tordo, Noël; Towner, Jonathan S.; Vasilakis, Nikos; Volchkov, Viktor E.; Wahl-Jensen, Victoria; Walker, Peter J.; Wang, Lin-Fa; Varsani, Arvind; Whitfield, Anna E.; Zerbini, F. Murilo; Kuhn, Jens H.

2016-10-22

Botanical, mycological, zoological, and prokaryotic species names follow the Linnaean format, consisting of an italicized Latinized binomen with a capitalized genus name and a lower case species epithet (e.g., Homo sapiens). Virus species names, however, do not follow a uniform format, and, even when binomial, are not Linnaean in style. In this thought exercise, we attempted to convert all currently official names of species included in the virus family Arenaviridae and the virus order Mononegavirales to Linnaean binomials, and to identify and address associated challenges and concerns. Surprisingly, this endeavor was not as complicated or time-consuming as even the authors of this article expected when conceiving the experiment. [Arenaviridae; binomials; ICTV; International Committee on Taxonomy of Viruses; Mononegavirales; virus nomenclature; virus taxonomy.

Pre-Ebola virus disease laboratory system and related challenges in Liberia

Directory of Open Access Journals (Sweden)

Stephen B. Kennedy

2016-10-01

Full Text Available Prior to the Ebola virus disease outbreak in Liberia, the laboratory system was duplicativefragmented and minimally coordinated. The National Reference Laboratory was conceptualisedto address the existing challenges by promoting the implementation of effective and sustainablelaboratory services in Liberia. However, in a resource-limited environment such as Liberiaprogress regarding the rebuilding of the health system can be relatively slow, while efforts tosustain the transient gains remain a key challenge for the Ministry of Health. In this paper, wedescribe the pre-Ebola virus disease laboratory system in Liberia and its prevailing efforts toaddress future emerging infectious diseases, as well as current Infectious diseases, all of whichare exacerbated by poverty. We conclude that laboratory and diagnostic services in Liberiahave encountered numerous challenges regarding its efforts to strengthen the healthcaredelivery system. These challenges include limited trained human resource capacity, inadequateinfrastructure, and a lack of coordination. As with most countries in sub-Saharan Africa, whencomparing urban and rural settings, diagnostic and clinical services are generally skewedtoward urban health facilities and private, faith-based health facilities. We recommend thatstructured policy be directed at these challenges for national institutions to develop guidelinesto improve, strengthen and sustain diagnostic and curative laboratory services to effectivelyaddress current infectious diseases and prepare for future emerging and re-emerging infectiousdiseases.

Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species.

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Hall, Jeffrey S; Franson, J Christian; Gill, Robert E; Meteyer, Carol U; TeSlaa, Joshua L; Nashold, Sean; Dusek, Robert J; Ip, Hon S

2011-09-01

Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds. Wild dunlin were inoculated intranasally and intrachoanally various doses of HPAIV H5N1. The birds were monitored daily for virus excretion, disease signs, morbidity, and mortality. The infectious dose of HPAIV H5N1 in dunlin was determined to be 10(1.7) EID(50)/100 μl and that the lethal dose was 10(1.83) EID(50)/100 μl. Clinical signs were consistent with neurotropic disease, and histochemical analyses revealed that infection was systemic with viral antigen and RNA most consistently found in brain tissues. Infected birds excreted relatively large amounts of virus orally (10(4) EID(50)) and smaller amounts cloacally. Dunlin are highly susceptible to infection with HPAIV H5N1. They become infected after exposure to relatively small doses of the virus and if they become infected, they are most likely to suffer mortality within 3-5 days. These results have important implications regarding the risks of transport and transmission of HPAIV H5N1 to North America by this species and raises questions for further investigation. Published 2011. This article is a US Government work and is in the public domain in the USA.

Zika virus infection confers protection against West Nile virus challenge in mice.

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Vázquez-Calvo, Ángela; Blázquez, Ana-Belén; Escribano-Romero, Estela; Merino-Ramos, Teresa; Saiz, Juan-Carlos; Martín-Acebes, Miguel A; Jiménez de Oya, Nereida

2017-09-20

Flaviviruses are RNA viruses that constitute a worrisome threat to global human and animal health. Zika virus (ZIKV), which was initially reported to cause a mild disease, recently spread in the Americas, infecting millions of people. During this recent epidemic, ZIKV infection has been linked to serious neurological diseases and birth defects, specifically Guillain-Barrè syndrome (GBS) and microcephaly. Because information about ZIKV immunity remains scarce, we assessed the humoral response of immunocompetent mice to infection with three viral strains of diverse geographical origin (Africa, Asia and America). No infected animals showed any sign of disease or died after infection. However, specific neutralizing antibodies were elicited in all infected mice. Considering the rapid expansion of ZIKV throughout the American continent and its co-circulation with other medically relevant flaviviruses, such as West Nile virus (WNV), the induction of protective immunity between ZIKV and WNV was analyzed. Remarkably, protection after challenge with WNV was observed in mice previously infected with ZIKV, as survival rates were significantly higher than in control mice. Moreover, previous ZIKV infection enhanced the humoral immune response against WNV. These findings may be relevant in geographical areas where both ZIKV and WNV co-circulate, as well as for the future development of broad-spectrum flavivirus vaccines.

Vaccines. An Ebola whole-virus vaccine is protective in nonhuman primates.

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Marzi, Andrea; Halfmann, Peter; Hill-Batorski, Lindsay; Feldmann, Friederike; Shupert, W Lesley; Neumann, Gabriele; Feldmann, Heinz; Kawaoka, Yoshihiro

2015-04-24

Zaire ebolavirus is the causative agent of the current outbreak of hemorrhagic fever disease in West Africa. Previously, we showed that a whole Ebola virus (EBOV) vaccine based on a replication-defective EBOV (EBOVΔVP30) protects immunized mice and guinea pigs against lethal challenge with rodent-adapted EBOV. Here, we demonstrate that EBOVΔVP30 protects nonhuman primates against lethal infection with EBOV. Although EBOVΔVP30 is replication-incompetent, we additionally inactivated the vaccine with hydrogen peroxide; the chemically inactivated vaccine remained antigenic and protective in nonhuman primates. EBOVΔVP30 thus represents a safe, efficacious, whole-EBOV vaccine candidate that differs from other EBOV vaccine platforms in that it presents all viral proteins and the viral RNA to the host immune system, which might contribute to protective immune responses. Copyright © 2015, American Association for the Advancement of Science.

A novel gE-deleted pseudorabies virus (PRV) provides rapid and complete protection from lethal challenge with the PRV variant emerging in Bartha-K61-vaccinated swine population in China.

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Wang, Chun-Hua; Yuan, Jin; Qin, Hua-Yang; Luo, Yuzi; Cong, Xin; Li, Yongfeng; Chen, Jianing; Li, Su; Sun, Yuan; Qiu, Hua-Ji

2014-06-05

The currently used Bartha-K61 strain is a very safe and effective vaccine against pseudorabies (PR) and has played a critical role in the control and eradication of PR worldwide. Since late 2011, however, PR reemerged among Bartha-K61-vaccinated pig population in many regions in China. Our previous studies demonstrated that the Bartha-K61 vaccine was unable to provide complete protection from the challenge with the PRV TJ strain (PRVTJ), a representative emerging PRV variant that was isolated from a Bartha-K61-immunized pig farm in Tianjin, China. Here, we generated a gE-deleted PRV, named as rPRVTJ-delgE, based on PRVTJ and evaluated its safety and immunogenicity in pigs. Our results showed that groups of piglets (n=5) immunized with 10(3), 10(4) or 10(5)TCID50 rPRVTJ-delgE did not exhibit clinical signs following immunization and challenge and were protected clinically and virologically from the lethal challenge with PRVTJ as early as 1 week post-immunization, in contrast with the incomplete protection provided by the Bartha-K61 vaccine. These indicate that rPRVTJ-delgE is a promising candidate vaccine for updating Bartha-K61 for the control of the currently epidemic PR in China. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structure of an antibody in complex with its mucin domain linear epitope that is protective against Ebola virus.

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Olal, Daniel; Kuehne, Ana I; Bale, Shridhar; Halfmann, Peter; Hashiguchi, Takao; Fusco, Marnie L; Lee, Jeffrey E; King, Liam B; Kawaoka, Yoshihiro; Dye, John M; Saphire, Erica Ollmann

2012-03-01

Antibody 14G7 is protective against lethal Ebola virus challenge and recognizes a distinct linear epitope in the prominent mucin-like domain of the Ebola virus glycoprotein GP. The structure of 14G7 in complex with its linear peptide epitope has now been determined to 2.8 Å. The structure shows that this GP sequence forms a tandem β-hairpin structure that binds deeply into a cleft in the antibody-combining site. A key threonine at the apex of one turn is critical for antibody interaction and is conserved among all Ebola viruses. This work provides further insight into the mechanism of protection by antibodies that target the protruding, highly accessible mucin-like domain of Ebola virus and the structural framework for understanding and characterizing candidate immunotherapeutics.

Effect of lethal and sub-lethal concentrations of tobacco (Nicotiana ...

African Journals Online (AJOL)

Lethal and sub-lethal bioassays on Clarias gariepinus were conducted to evaluate the toxicity of tobacco (Nicotiana tobaccum) leaf dust on weight gain and haematological indices of Clarias gariepinus (mean weight 10.5±0.70g) in glass aquaria with aeration system. The concentrations used during the lethal exposure are: ...

Pre- and post-exposure safety and efficacy of attenuated rabies virus vaccines are enhanced by their expression of IFNγ

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Barkhouse, Darryll A. [Department of Cancer Biology, 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Center for Neurovirology 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Faber, Milosz [Center for Neurovirology 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Department of Microbiology and Immunology 1020 Locust St., Jefferson Alumni Hall, Room 465, Philadelphia, PA 19107 (United States); Hooper, D. Craig, E-mail: douglas.hooper@jefferson.edu [Department of Cancer Biology, 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Department of Neurological Surgery, 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Center for Neurovirology 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States)

2015-01-01

Consistent with evidence of a strong correlation between interferon gamma (IFNγ) production and rabies virus (RABV) clearance from the CNS, we recently demonstrated that engineering a pathogenic RABV to express IFNγ highly attenuates the virus. Reasoning that IFNγ expression by RABV vaccines would enhance their safety and efficacy, we reverse-engineered two proven vaccine vectors, GAS and GASGAS, to express murine IFNγ. Mortality and morbidity were monitored during suckling mice infection, immunize/challenge experiments and mixed intracranial infections. We demonstrate that GASγ and GASγGAS are significantly attenuated in suckling mice compared to the GASGAS vaccine. GASγ better protects mice from lethal DRV4 RABV infection in both pre- and post-exposure experiments compared to GASGAS. Finally, GASγGAS reduces post-infection neurological sequelae, compared to control, during mixed intracranial infection with DRV4. These data show IFNγ expression by a vaccine vector can enhance its safety while increasing its efficacy as pre- and post-exposure treatment. - Highlights: • IFNγ expression improves attenuated rabies virus safety and immunogenicity. • IFNγ expression is safer and more immunogenic than doubling glycoprotein expression. • Co-infection with IFNγ-expressing RABV prevents wild-type rabies virus lethality. • Vaccine safety and efficacy is additive for IFNγ and double glycoprotein expression.

Pre- and post-exposure safety and efficacy of attenuated rabies virus vaccines are enhanced by their expression of IFNγ

International Nuclear Information System (INIS)

Barkhouse, Darryll A.; Faber, Milosz; Hooper, D. Craig

2015-01-01

Consistent with evidence of a strong correlation between interferon gamma (IFNγ) production and rabies virus (RABV) clearance from the CNS, we recently demonstrated that engineering a pathogenic RABV to express IFNγ highly attenuates the virus. Reasoning that IFNγ expression by RABV vaccines would enhance their safety and efficacy, we reverse-engineered two proven vaccine vectors, GAS and GASGAS, to express murine IFNγ. Mortality and morbidity were monitored during suckling mice infection, immunize/challenge experiments and mixed intracranial infections. We demonstrate that GASγ and GASγGAS are significantly attenuated in suckling mice compared to the GASGAS vaccine. GASγ better protects mice from lethal DRV4 RABV infection in both pre- and post-exposure experiments compared to GASGAS. Finally, GASγGAS reduces post-infection neurological sequelae, compared to control, during mixed intracranial infection with DRV4. These data show IFNγ expression by a vaccine vector can enhance its safety while increasing its efficacy as pre- and post-exposure treatment. - Highlights: • IFNγ expression improves attenuated rabies virus safety and immunogenicity. • IFNγ expression is safer and more immunogenic than doubling glycoprotein expression. • Co-infection with IFNγ-expressing RABV prevents wild-type rabies virus lethality. • Vaccine safety and efficacy is additive for IFNγ and double glycoprotein expression

A novel recombinant pseudorabies virus expressing parvovirus VP2 gene: Immunogenicity and protective efficacy in swine.

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Chen, Yang; Guo, Wanzhu; Xu, Zhiwen; Yan, Qigui; Luo, Yan; Shi, Qian; Chen, Dishi; Zhu, Ling; Wang, Xiaoyu

2011-06-16

Porcine parvovirus (PPV) VP2 gene has been successfully expressed in many expression systems resulting in self-assembly of virus-like particles (VLPs) with similar morphology to the native capsid. Here, a pseudorabies virus (PRV) system was adopted to express the PPV VP2 gene. A recombinant PRV SA215/VP2 was obtained by homologous recombination between the vector PRV viral DNA and a transfer plasmid. Then recombinant virus was purified with plaque purification, and its identity confirmed by PCR amplification, Western blot and indirect immunofluorescence (IFA) analyses. Electronic microscopy of PRV SA215/VP2 confirmed self-assembly of both pseudorabies virus and VLPs from VP2 protein. Immunization of piglets with recombinant virus elicited PRV-specific and PPV-specific humoral immune responses and provided complete protection against a lethal dose of PRV challenges. Gilts immunized with recombinant viruses induced PPV-specific antibodies, and significantly reduced the mortality rate of (1 of 28) following virulent PPV challenge compared with the control (7 of 31). Furthermore, PPV virus DNA was not detected in the fetuses of recombinant virus immunized gilts. In this study, a recombinant PRV SA215/VP2 virus expressing PPV VP2 protein was constructed using PRV SA215 vector. The safety, immunogenicity, and protective efficacy of the recombinant virus were demonstrated in piglets and primiparous gilts. This recombinant PRV SA215/VP2 represents a suitable candidate for the development of a bivalent vaccine against both PRV and PPV infection.

Recombinant canine distemper virus serves as bivalent live vaccine against rabies and canine distemper.

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Wang, Xijun; Feng, Na; Ge, Jinying; Shuai, Lei; Peng, Liyan; Gao, Yuwei; Yang, Songtao; Xia, Xianzhu; Bu, Zhigao

2012-07-20

Effective, safe, and affordable rabies vaccines are still being sought. Attenuated live vaccine has been widely used to protect carnivores from canine distemper. In this study, we generated a recombinant canine distemper virus (CDV) vaccine strain, rCDV-RVG, expressing the rabies virus glycoprotein (RVG) by using reverse genetics. The recombinant virus rCDV-RVG retained growth properties similar to those of vector CDV in Vero cell culture. Animal studies demonstrated that rCDV-RVG was safe in mice and dogs. Mice inoculated intracerebrally or intramuscularly with rCDV-RVG showed no apparent signs of disease and developed a strong rabies virus (RABV) neutralizing antibody response, which completely protected mice from challenge with a lethal dose of street virus. Canine studies showed that vaccination with rCDV-RVG induced strong and long-lasting virus neutralizing antibody responses to RABV and CDV. This is the first study demonstrating that recombinant CDV has the potential to serve as bivalent live vaccine against rabies and canine distemper in animals. Copyright © 2012 Elsevier Ltd. All rights reserved.

Immunization of Mice with Anthrax Protective Antigen Limits Cardiotoxicity but Not Hepatotoxicity Following Lethal Toxin Challenge

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T. Scott Devera

2015-06-01

Full Text Available Protective immunity against anthrax is inferred from measurement of vaccine antigen-specific neutralizing antibody titers in serum samples. In animal models, in vivo challenges with toxin and/or spores can also be performed. However, neither of these approaches considers toxin-induced damage to specific organ systems. It is therefore important to determine to what extent anthrax vaccines and existing or candidate adjuvants can provide organ-specific protection against intoxication. We therefore compared the ability of Alum, CpG DNA and the CD1d ligand α-galactosylceramide (αGC to enhance protective antigen-specific antibody titers, to protect mice against challenge with lethal toxin, and to block cardiotoxicity and hepatotoxicity. By measurement of serum cardiac Troponin I (cTnI, and hepatic alanine aminotransferase (ALT, and aspartate aminotransferase (AST, it was apparent that neither vaccine modality prevented hepatic intoxication, despite high Ab titers and ultimate survival of the subject. In contrast, cardiotoxicity was greatly diminished by prior immunization. This shows that a vaccine that confers survival following toxin exposure may still have an associated morbidity. We propose that organ-specific intoxication should be monitored routinely during research into new vaccine modalities.

The Carbomer-Lecithin Adjuvant Adjuplex Has Potent Immunoactivating Properties and Elicits Protective Adaptive Immunity against Influenza Virus Challenge in Mice

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Wegmann, Frank; Moghaddam, Amin E.; Schiffner, Torben; Gartlan, Kate H.; Powell, Timothy J.; Russell, Rebecca A.; Baart, Matthijs; Carrow, Emily W.

2015-01-01

The continued discovery and development of adjuvants for vaccine formulation are important to safely increase potency and/or reduce the antigen doses of existing vaccines and tailor the adaptive immune response to newly developed vaccines. Adjuplex is a novel adjuvant platform based on a purified lecithin and carbomer homopolymer. Here, we analyzed the adjuvant activity of Adjuplex in mice for the soluble hemagglutinin (HA) glycoprotein of influenza A virus. The titration of Adjuplex revealed an optimal dose of 1% for immunogenicity, eliciting high titers of HA-specific IgG but inducing no significant weight loss. At this dose, Adjuplex completely protected mice from an otherwise lethal influenza virus challenge and was at least as effective as the adjuvants monophosphoryl lipid A (MPL) and alum in preventing disease. Adjuplex elicited balanced Th1-/Th2-type immune responses with accompanying cytokines and triggered antigen-specific CD8+ T-cell proliferation. The use of the peritoneal inflammation model revealed that Adjuplex recruited dendritic cells (DCs), monocytes, and neutrophils in the context of innate cytokine and chemokine secretion. Adjuplex neither triggered classical maturation of DCs nor activated a pathogen recognition receptor (PRR)-expressing NF-κB reporter cell line, suggesting a mechanism of action different from that reported for classical pathogen-associated molecular pattern (PAMP)-activated innate immunity. Taken together, these data reveal Adjuplex to be a potent and well-tolerated adjuvant with application for subunit vaccines. PMID:26135973

Inhibitory effects of bee venom and its components against viruses in vitro and in vivo.

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Uddin, Md Bashir; Lee, Byeong-Hoon; Nikapitiya, Chamilani; Kim, Jae-Hoon; Kim, Tae-Hwan; Lee, Hyun-Cheol; Kim, Choul Goo; Lee, Jong-Soo; Kim, Chul-Joong

2016-12-01

Bee venom (BV) from honey bee (Apis Melifera L.) contains at least 18 pharmacologically active components including melittin (MLT), phospholipase A 2 (PLA 2 ), and apamin etc. BV is safe for human treatments dose dependently and proven to possess different healing properties including antibacterial and antiparasitidal properties. Nevertheless, antiviral properties of BV have not well investigated. Hence, we identified the potential antiviral properties of BV and its component against a broad panel of viruses. Co-incubation of non-cytotoxic amounts of BV and MLT, the main component of BV, significantly inhibited the replication of enveloped viruses such as Influenza A virus (PR8), Vesicular Stomatitis Virus (VSV), Respiratory Syncytial Virus (RSV), and Herpes Simplex Virus (HSV). Additionally, BV and MLT also inhibited the replication of non-enveloped viruses such as Enterovirus-71 (EV-71) and Coxsackie Virus (H3). Such antiviral properties were mainly explained by virucidal mechanism. Moreover, MLT protected mice which were challenged with lethal doses of pathogenic influenza A H1N1 viruses. Therefore, these results provides the evidence that BV and MLT could be a potential source as a promising antiviral agent, especially to develop as a broad spectrum antiviral agent.

Safety evaluation of a recombinant myxoma-RHDV virus inducing horizontal transmissible protection against myxomatosis and rabbit haemorrhagic disease.

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Torres, J M; Ramírez, M A; Morales, M; Bárcena, J; Vázquez, B; Espuña, E; Pagès-Manté, A; Sánchez-Vizcaíno, J M

2000-09-15

We have recently developed a transmissible vaccine to immunize rabbits against myxomatosis and rabbit haemorrhagic disease based on a recombinant myxoma virus (MV) expressing the rabbit haemorrhagic disease virus (RHDV) capsid protein [Bárcena et al. Horizontal transmissible protection against myxomatosis and rabbit haemorragic disease using a recombinant myxoma virus. J. Virol. 2000;74:1114-23]. Administration of the recombinant virus protects rabbits against lethal RHDV and MV challenges. Furthermore, the recombinant virus is capable of horizontal spreading promoting protection of contact animals, thus providing the opportunity to immunize wild rabbit populations. However, potential risks must be extensively evaluated before considering its field use. In this study several safety issues concerning the proposed vaccine have been evaluated under laboratory conditions. Results indicated that vaccine administration is safe even at a 100-fold overdose. No undesirable effects were detected upon administration to immunosuppressed or pregnant rabbits. The recombinant virus maintained its attenuated phenotype after 10 passages in vivo.

Studies on the susceptibility of ostriches (Struthio camelus to the Indonesian velogenic strain of Newcastle disease virus

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Darminto

1998-12-01

Full Text Available Susceptibility of ostriches (Struthio camelus to the Indonesian velogenic strain of Newcastle disease virus (NDV was evaluated by artificial infection . Twelve - 5 to 6 week old ostriches were divided into 3 groups each containing 4 birds . The first group was inoculated through respiratory system by dropping directly the virus solution into the nostrils, while the second group was inoculated through digestive system by dropping directly the virus solution into the oesophagus, with the dose of infection 106ELDSo (50%-embryo lethal dose per bird . Meanwhile, the third group was treated as uninfected control . All infected birds developed antibody responses, but only two inoculated birds from the first group and two inoculated birds from the second group developed clinical signs of Newcastle disease (ND, with no specific pathological alterations . Infected birds, either sicks or healthy, excreted the challenge viruses through the respiratory system and still be detected up to the end of this experiment, ie . 15 days post-inoculation . The challenge viruses can be re-isolated from the brain, trachea, lungs, heart, liver, spleen, kidneys, small intestine, cecal-tonsil, and proventriculus of the infected birds . This study concludes that: (1 the ostriches are susceptible to the infection of the Indonesian velogenic strain ofNDV; (2 all infected birds developed immune responses, but only half of them develops el jtigi aj i disease ; (3 the infected birds excreted the challenge viruses for a considerable long time which may play role as the Mginiseti.ce ofinfectron the other healthy ostriches ; and (4 the challenge viruses can be re-isolated from various organs of the birds . .

Recombinant raccoon pox vaccine protects mice against lethal plague

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Osorio, J.E.; Powell, T.D.; Frank, R.S.; Moss, K.; Haanes, E.J.; Smith, S.R.; Rocke, T.E.; Stinchcomb, D.T.

2003-01-01

Using a raccoon poxvirus (RCN) expression system, we have developed new recombinant vaccines that can protect mice against lethal plague infection. We tested the effects of a translation enhancer (EMCV-IRES) in combination with a secretory (tPA) signal or secretory (tPA) and membrane anchoring (CHV-gG) signals on in vitro antigen expression of F1 antigen in tissue culture and the induction of antibody responses and protection against Yersinia pestis challenge in mice. The RCN vector successfully expressed the F1 protein of Y. pestis in vitro. In addition, the level of expression was increased by the insertion of the EMCV-IRES and combinations of this and the secretory signal or secretory and anchoring signals. These recombinant viruses generated protective immune responses that resulted in survival of 80% of vaccinated mice upon challenge with Y. pestis. Of the RCN-based vaccines we tested, the RCN-IRES-tPA-YpF1 recombinant construct was the most efficacious. Mice vaccinated with this construct withstood challenge with as many as 1.5 million colony forming units of Y. pestis (7.7×104 LD50). Interestingly, vaccination with F1 fused to the anchoring signal (RCN-IRES-tPA-YpF1-gG) elicited significant anti-F1 antibody titers, but failed to protect mice from plague challenge. Our studies demonstrate, in vitro and in vivo, the potential importance of the EMCV-IRES and secretory signals in vaccine design. These molecular tools provide a new approach for improving the efficacy of vaccines. In addition, these novel recombinant vaccines could have human, veterinary, and wildlife applications in the prevention of plague.

Lactobacillus priming of the respiratory tract: Heterologous immunity and protection against lethal pneumovirus infection.

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Garcia-Crespo, Katia E; Chan, Calvin C; Gabryszewski, Stanislaw J; Percopo, Caroline M; Rigaux, Peter; Dyer, Kimberly D; Domachowske, Joseph B; Rosenberg, Helene F

2013-03-01

We showed previously that wild-type mice primed via intranasal inoculation with live or heat-inactivated Lactobacillus species were fully (100%) protected against the lethal sequelae of infection with the virulent pathogen, pneumonia virus of mice (PVM), a response that is associated with diminished expression of proinflammatory cytokines and diminished virus recovery. We show here that 40% of the mice primed with live Lactobacillus survived when PVM challenge was delayed for 5months. This robust and sustained resistance to PVM infection resulting from prior interaction with an otherwise unrelated microbe is a profound example of heterologous immunity. We undertook the present study in order to understand the nature and unique features of this response. We found that intranasal inoculation with L. reuteri elicited rapid, transient neutrophil recruitment in association with proinflammatory mediators (CXCL1, CCL3, CCL2, CXCL10, TNF-alpha and IL-17A) but not Th1 cytokines. IFNγ does not contribute to survival promoted by Lactobacillus-priming. Live L. reuteri detected in lung tissue underwent rapid clearance, and was undetectable at 24h after inoculation. In contrast, L. reuteri peptidoglycan (PGN) and L. reuteri genomic DNA (gDNA) were detected at 24 and 48h after inoculation, respectively. In contrast to live bacteria, intranasal inoculation with isolated L. reuteri gDNA elicited no neutrophil recruitment, had minimal impact on virus recovery and virus-associated production of CCL3, and provided no protection against the negative sequelae of virus infection. Isolated PGN elicited neutrophil recruitment and proinflammatory cytokines but did not promote sustained survival in response to subsequent PVM infection. Overall, further evaluation of the responses leading to Lactobacillus-mediated heterologous immunity may provide insight into novel antiviral preventive modalities. Published by Elsevier B.V.

A novel challenge test incorporating irradiation (60Co) of compost sub-samples to validate thermal lethality towards pathogenic bacteria.

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Moore, John E; Watabe, Miyuki; Stewart, Andrew; Cherie Millar, B; Rao, Juluri R

2009-01-01

Maturing compost heaps normally attaining temperatures ranging from 55 to 65 degrees C is generally regarded to conform to recommended biological risks and sanitation standards for composts stipulated by either EU or US-EPA. Composted products derived from animal sources are further required by EU biohazard safety regulatory legislation that such composts either attain 70 degrees C for over 3h during maturation or via treatment at 70 degrees C for 1h before being considered for dispensation on land. The setting of the upper limit of thermal lethality at 70 degrees C/1h for achieving biosecurity of the animal waste composted products (e.g. pelleted fertilizer formulations) is not properly substantiated by specific validation tests, comprising a 'wipe-out' step (usually via autoclaving) followed by inoculation of a prescribed bacterium, exposure to 70 degrees C/1h and the lethality determined. Pelleted formulations of composts are not amenable for wet methods (autoclaving) for wipe-out sterilization step as this is detrimental to the pellet and compromises sample integrity. This study describes a laboratory method involving the employment of ((60)Co) irradiation 'wipe-out' step to: (a) compost sub-samples drawn from compost formulation heaps and (b) pelleted products derived from composted animal products while determining the thermal lethality of a given time/temperature (70 degrees C/1h) treatment process and by challenging the irradiated sample (not just with one bacterium but), out with 10 potential food-poisoning organisms from the bacterial genera (Campylobacter, Escherichia, Listeria, Salmonella, Yersinia) frequently detected in pig and poultry farm wastes. This challenge test on compost sub-samples can be a useful intervention ploy for 'inspection and validation' technique for composters during the compost maturity process, whose attainment of temperatures of 55-65 degrees C is presumed sufficient for attainment of sanitation. Stringent measures are further

Vaccination against H9N2 avian influenza virus reduces bronchus-associated lymphoid tissue formation in cynomolgus macaques after intranasal virus challenge infection.

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Nakayama, Misako; Ozaki, Hiroichi; Itoh, Yasushi; Soda, Kosuke; Ishigaki, Hirohito; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Park, Chun-Ho; Tsuchiya, Hideaki; Kida, Hiroshi; Ogasawara, Kazumasa

2016-12-01

H9N2 avian influenza virus causes sporadic human infection. Since humans do not possess acquired immunity specific to this virus, we examined the pathogenicity of an H9N2 virus isolated from a human and then analyzed protective effects of a vaccine in cynomolgus macaques. After intranasal challenge with A/Hong Kong/1073/1999 (H9N2) (HK1073) isolated from a human patient, viruses were isolated from nasal and tracheal swabs in unvaccinated macaques with mild fever and body weight loss. A formalin-inactivated H9N2 whole particle vaccine derived from our virus library was subcutaneously inoculated to macaques. Vaccination induced viral antigen-specific IgG and neutralization activity in sera. After intranasal challenge with H9N2, the virus was detected only the day after inoculation in the vaccinated macaques. Without vaccination, many bronchus-associated lymphoid tissues (BALTs) were formed in the lungs after infection, whereas the numbers of BALTs were smaller and the cytokine responses were weaker in the vaccinated macaques than those in the unvaccinated macaques. These findings indicate that the H9N2 avian influenza virus HK1073 is pathogenic in primates but seems to cause milder symptoms than does H7N9 influenza virus as found in our previous studies and that a formalin-inactivated H9N2 whole particle vaccine induces protective immunity against H9N2 virus. © 2016 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

Linear DNA vaccine prepared by large-scale PCR provides protective immunity against H1N1 influenza virus infection in mice.

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Wang, Fei; Chen, Quanjiao; Li, Shuntang; Zhang, Chenyao; Li, Shanshan; Liu, Min; Mei, Kun; Li, Chunhua; Ma, Lixin; Yu, Xiaolan

2017-06-01

Linear DNA vaccines provide effective vaccination. However, their application is limited by high cost and small scale of the conventional polymerase chain reaction (PCR) generally used to obtain sufficient amounts of DNA effective against epidemic diseases. In this study, a two-step, large-scale PCR was established using a low-cost DNA polymerase, RKOD, expressed in Pichia pastoris. Two linear DNA vaccines encoding influenza H1N1 hemagglutinin (HA) 1, LEC-HA, and PTO-LEC-HA (with phosphorothioate-modified primers), were produced by the two-step PCR. Protective effects of the vaccines were evaluated in a mouse model. BALB/c mice were immunized three times with the vaccines or a control DNA fragment. All immunized animals were challenged by intranasal administration of a lethal dose of influenza H1N1 virus 2 weeks after the last immunization. Sera of the immunized animals were tested for the presence of HA-specific antibodies, and the total IFN-γ responses induced by linear DNA vaccines were measured. The results showed that the DNA vaccines but not the control DNA induced strong antibody and IFN-γ responses. Additionally, the PTO-LEC-HA vaccine effectively protected the mice against the lethal homologous mouse-adapted virus, with a survival rate of 100% versus 70% in the LEC-HA-vaccinated group, showing that the PTO-LEC-HA vaccine was more effective than LEC-HA. In conclusion, the results indicated that the linear H1N1 HA-coding DNA vaccines induced significant immune responses and protected mice against a lethal virus challenge. Thus, the low-cost, two-step, large-scale PCR can be considered a potential tool for rapid manufacturing of linear DNA vaccines against emerging infectious diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Lethality Index 2008-2014: Less shootings, same lethality, more opacity

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Carlos Silva Forné

2017-11-01

Full Text Available This article evaluates the use of lethal force by Mexican federal security forces during shootings with presumed members of organized crime from 2008-2014. The authors use official data and press reports on deaths and wounded in shootings to construct indicators such as the number of dead civilians over the number of dead officials from the federal security forces and the number of dead civilians over the number of wounded civilians. In a context where certain factors that contribute to an excessive use of force become more common, the results of the study show a growing use of lethal force. This raises questions over the possible excessive use of lethal force as a normal or systematic practice. The study also shows a growing context of opacity in the information available to evaluate the use of lethal force and the general lack of a legal framework to regulate the use of lethal force in Mexico.

Identification of a Novel RNA Virus Lethal to Tilapia

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Eyngor, Marina; Zamostiano, Rachel; Kembou Tsofack, Japhette Esther; Berkowitz, Asaf; Bercovier, Hillel; Tinman, Simon; Lev, Menachem; Hurvitz, Avshalom; Galeotti, Marco; Eldar, Avi

2014-01-01

Tilapines are important for the sustainability of ecological systems and serve as the second most important group of farmed fish worldwide. Significant mortality of wild and cultured tilapia has been observed recently in Israel. The etiological agent of this disease, a novel RNA virus, is described here, and procedures allowing its isolation and detection are revealed. The virus, denominated tilapia lake virus (TiLV), was propagated in primary tilapia brain cells or in an E-11 cell line, and it induced a cytopathic effect at 5 to 10 days postinfection. Electron microscopy revealed enveloped icosahedral particles of 55 to 75 nm. Low-passage TiLV, injected intraperitoneally in tilapia, induced a disease resembling the natural disease, which typically presents with lethargy, ocular alterations, and skin erosions, with >80% mortality. Histological changes included congestion of the internal organs (kidneys and brain) with foci of gliosis and perivascular cuffing of lymphocytes in the brain cortex; ocular inflammation included endophthalmitis and cataractous changes of the lens. The cohabitation of healthy and diseased fish demonstrated that the disease is contagious and that mortalities (80 to 100%) occur within a few days. Fish surviving the initial mortality were immune to further TiLV infections, suggesting the mounting of a protective immune response. Screening cDNA libraries identified a TiLV-specific sequence, allowing the design of a PCR-based diagnostic test. This test enables the specific identification of TiLV in tilapines and should help control the spread of this virus worldwide. PMID:25232154

Potent neutralization of influenza A virus by a single-domain antibody blocking M2 ion channel protein.

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Guowei Wei

Full Text Available Influenza A virus poses serious health threat to humans. Neutralizing antibodies against the highly conserved M2 ion channel is thought to offer broad protection against influenza A viruses. Here, we screened synthetic Camel single-domain antibody (VHH libraries against native M2 ion channel protein. One of the isolated VHHs, M2-7A, specifically bound to M2-expressed cell membrane as well as influenza A virion, inhibited replication of both amantadine-sensitive and resistant influenza A viruses in vitro, and protected mice from a lethal influenza virus challenge. Moreover, M2-7A showed blocking activity for proton influx through M2 ion channel. These pieces of evidence collectively demonstrate for the first time that a neutralizing antibody against M2 with broad specificity is achievable, and M2-7A may have potential for cross protection against a number of variants and subtypes of influenza A viruses.

Inactivated Recombinant Rabies Viruses Displaying Canine Distemper Virus Glycoproteins Induce Protective Immunity against Both Pathogens

OpenAIRE

da Fontoura Budaszewski, Renata; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Yin, Xiangping; Schnell, Matthias J.; von Messling, Veronika

2017-01-01

The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Both canine distemper virus (CDV) and rabies virus (RABV) cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wildlife species. In this study, we developed recombinant bivalent vaccine candidates based on recombinant ...

A20 (Tnfaip3 deficiency in myeloid cells protects against influenza A virus infection.

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Jonathan Maelfait

Full Text Available The innate immune response provides the first line of defense against viruses and other pathogens by responding to specific microbial molecules. Influenza A virus (IAV produces double-stranded RNA as an intermediate during the replication life cycle, which activates the intracellular pathogen recognition receptor RIG-I and induces the production of proinflammatory cytokines and antiviral interferon. Understanding the mechanisms that regulate innate immune responses to IAV and other viruses is of key importance to develop novel therapeutic strategies. Here we used myeloid cell specific A20 knockout mice to examine the role of the ubiquitin-editing protein A20 in the response of myeloid cells to IAV infection. A20 deficient macrophages were hyperresponsive to double stranded RNA and IAV infection, as illustrated by enhanced NF-κB and IRF3 activation, concomitant with increased production of proinflammatory cytokines, chemokines and type I interferon. In vivo this was associated with an increased number of alveolar macrophages and neutrophils in the lungs of IAV infected mice. Surprisingly, myeloid cell specific A20 knockout mice are protected against lethal IAV infection. These results challenge the general belief that an excessive host proinflammatory response is associated with IAV-induced lethality, and suggest that under certain conditions inhibition of A20 might be of interest in the management of IAV infections.

DNA vaccine encoding nucleocapsid and surface proteins of wild type canine distemper virus protects its natural host against distemper.

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Cherpillod, P; Tipold, A; Griot-Wenk, M; Cardozo, C; Schmid, I; Fatzer, R; Schobesberger, M; Zurbriggen, R; Bruckner, L; Roch, F; Vandevelde, M; Wittek, R; Zurbriggen, A

2000-07-01

Canine distemper virus (CDV), a member of the genus Morbillivirus induces a highly infectious, frequently lethal disease in dogs and other carnivores. Current vaccines against canine distemper consisting of attenuated viruses have been in use for many years and have greatly reduced the incidence of distemper in the dog population. However, certain strains may not guarantee adequate protection and others can induce post vaccinal encephalitis. We tested a DNA vaccine for its ability to protect dogs, the natural host of CDV, against distemper. We constructed plasmids containing the nucleocapsid, the fusion, and the attachment protein genes of a virulent canine distemper virus strain. Mice inoculated with these plasmids developed humoral and cellular immune responses against CDV antigens. Dogs immunized with the expression plasmids developed virus-neutralizing antibodies. Significantly, vaccinated dogs were protected against challenge with virulent CDV, whereas unvaccinated animals succumbed to distemper.

A novel recombinant pseudorabies virus expressing parvovirus VP2 gene: Immunogenicity and protective efficacy in swine

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Chen Dishi

2011-06-01

Full Text Available Abstract Background Porcine parvovirus (PPV VP2 gene has been successfully expressed in many expression systems resulting in self-assembly of virus-like particles (VLPs with similar morphology to the native capsid. Here, a pseudorabies virus (PRV system was adopted to express the PPV VP2 gene. Methods A recombinant PRV SA215/VP2 was obtained by homologous recombination between the vector PRV viral DNA and a transfer plasmid. Then recombinant virus was purified with plaque purification, and its identity confirmed by PCR amplification, Western blot and indirect immunofluorescence (IFA analyses. Electronic microscopy of PRV SA215/VP2 confirmed self-assembly of both pseudorabies virus and VLPs from VP2 protein. Results Immunization of piglets with recombinant virus elicited PRV-specific and PPV-specific humoral immune responses and provided complete protection against a lethal dose of PRV challenges. Gilts immunized with recombinant viruses induced PPV-specific antibodies, and significantly reduced the mortality rate of (1 of 28 following virulent PPV challenge compared with the control (7 of 31. Furthermore, PPV virus DNA was not detected in the fetuses of recombinant virus immunized gilts. Conclusions In this study, a recombinant PRV SA215/VP2 virus expressing PPV VP2 protein was constructed using PRV SA215 vector. The safety, immunogenicity, and protective efficacy of the recombinant virus were demonstrated in piglets and primiparous gilts. This recombinant PRV SA215/VP2 represents a suitable candidate for the development of a bivalent vaccine against both PRV and PPV infection.

The Mutational Robustness of Influenza A Virus.

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Elisa Visher

2016-08-01

Full Text Available A virus' mutational robustness is described in terms of the strength and distribution of the mutational fitness effects, or MFE. The distribution of MFE is central to many questions in evolutionary theory and is a key parameter in models of molecular evolution. Here we define the mutational fitness effects in influenza A virus by generating 128 viruses, each with a single nucleotide mutation. In contrast to mutational scanning approaches, this strategy allowed us to unambiguously assign fitness values to individual mutations. The presence of each desired mutation and the absence of additional mutations were verified by next generation sequencing of each stock. A mutation was considered lethal only after we failed to rescue virus in three independent transfections. We measured the fitness of each viable mutant relative to the wild type by quantitative RT-PCR following direct competition on A549 cells. We found that 31.6% of the mutations in the genome-wide dataset were lethal and that the lethal fraction did not differ appreciably between the HA- and NA-encoding segments and the rest of the genome. Of the viable mutants, the fitness mean and standard deviation were 0.80 and 0.22 in the genome-wide dataset and best modeled as a beta distribution. The fitness impact of mutation was marginally lower in the segments coding for HA and NA (0.88 ± 0.16 than in the other 6 segments (0.78 ± 0.24, and their respective beta distributions had slightly different shape parameters. The results for influenza A virus are remarkably similar to our own analysis of CirSeq-derived fitness values from poliovirus and previously published data from other small, single stranded DNA and RNA viruses. These data suggest that genome size, and not nucleic acid type or mode of replication, is the main determinant of viral mutational fitness effects.

The type IV pilin of Burkholderia mallei is highly immunogenic but fails to protect against lethal aerosol challenge in a murine model.

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Fernandes, Paula J; Guo, Qin; Waag, David M; Donnenberg, Michael S

2007-06-01

Burkholderia mallei is the cause of glanders and a proven biological weapon. We identified and purified the type IV pilin protein of this organism to study its potential as a subunit vaccine. We found that purified pilin was highly immunogenic. Furthermore, mice infected via sublethal aerosol challenge developed significant increases in titers of antibody against the pilin, suggesting that it is expressed in vivo. Nevertheless, we found no evidence that high-titer antipilin antisera provided passive protection against a sublethal or lethal aerosol challenge and no evidence of protection afforded by active immunization with purified pilin. These results contrast with the utility of type IV pilin subunit vaccines against other infectious diseases and highlight the need for further efforts to identify protective responses against this pathogen.

Fine-tuning synthesis of Yersinia pestis LcrV from runaway-like replication balanced-lethal plasmid in a Salmonella enterica serovar typhimurium vaccine induces protection against a lethal Y. pestis challenge in mice.

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Torres-Escobar, Ascención; Juárez-Rodríguez, María Dolores; Gunn, Bronwyn M; Branger, Christine G; Tinge, Steven A; Curtiss, Roy

2010-06-01

A balanced-lethal plasmid expression system that switches from low-copy-number to runaway-like high-copy-number replication (pYA4534) was constructed for the regulated delayed in vivo synthesis of heterologous antigens by vaccine strains. This is an antibiotic resistance-free maintenance system containing the asdA gene (essential for peptidoglycan synthesis) as a selectable marker to complement the lethal chromosomal DeltaasdA allele in live recombinant attenuated Salmonella vaccines (RASVs) such as Salmonella enterica serovar Typhimurium strain chi9447. pYA4534 harbors two origins of replication, pSC101 and pUC (low and high copy numbers, respectively). The pUC replication origin is controlled by a genetic switch formed by the operator/promoter of the P22 cro gene (O/P(cro)) (P(R)), which is negatively regulated by an arabinose-inducible P22 c2 gene located on both the plasmid and the chromosome (araC P(BAD) c2). The absence of arabinose, which is unavailable in vivo, triggers replication to a high-copy-number plasmid state. To validate these vector attributes, the Yersinia pestis virulence antigen LcrV was used to develop a vaccine against plague. An lcrV sequence encoding amino acids 131 to 326 (LcrV196) was optimized for expression in Salmonella, flanked with nucleotide sequences encoding the signal peptide (SS) and the carboxy-terminal domain (CT) of beta-lactamase, and cloned into pYA4534 under the control of the P(trc) promoter to generate plasmid pYA4535. Our results indicate that the live Salmonella vaccine strain chi9447 harboring pYA4535 efficiently stimulated a mixed Th1/Th2 immune response that protected mice against lethal challenge with Y. pestis strain CO92 introduced through either the intranasal or subcutaneous route.

Fine-Tuning Synthesis of Yersinia pestis LcrV from Runaway-Like Replication Balanced-Lethal Plasmid in a Salmonella enterica Serovar Typhimurium Vaccine Induces Protection against a Lethal Y. pestis Challenge in Mice▿

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Torres-Escobar, Ascención; Juárez-Rodríguez, María Dolores; Gunn, Bronwyn M.; Branger, Christine G.; Tinge, Steven A.; Curtiss, Roy

2010-01-01

A balanced-lethal plasmid expression system that switches from low-copy-number to runaway-like high-copy-number replication (pYA4534) was constructed for the regulated delayed in vivo synthesis of heterologous antigens by vaccine strains. This is an antibiotic resistance-free maintenance system containing the asdA gene (essential for peptidoglycan synthesis) as a selectable marker to complement the lethal chromosomal ΔasdA allele in live recombinant attenuated Salmonella vaccines (RASVs) such as Salmonella enterica serovar Typhimurium strain χ9447. pYA4534 harbors two origins of replication, pSC101 and pUC (low and high copy numbers, respectively). The pUC replication origin is controlled by a genetic switch formed by the operator/promoter of the P22 cro gene (O/Pcro) (PR), which is negatively regulated by an arabinose-inducible P22 c2 gene located on both the plasmid and the chromosome (araC PBAD c2). The absence of arabinose, which is unavailable in vivo, triggers replication to a high-copy-number plasmid state. To validate these vector attributes, the Yersinia pestis virulence antigen LcrV was used to develop a vaccine against plague. An lcrV sequence encoding amino acids 131 to 326 (LcrV196) was optimized for expression in Salmonella, flanked with nucleotide sequences encoding the signal peptide (SS) and the carboxy-terminal domain (CT) of β-lactamase, and cloned into pYA4534 under the control of the Ptrc promoter to generate plasmid pYA4535. Our results indicate that the live Salmonella vaccine strain χ9447 harboring pYA4535 efficiently stimulated a mixed Th1/Th2 immune response that protected mice against lethal challenge with Y. pestis strain CO92 introduced through either the intranasal or subcutaneous route. PMID:20308296

Protective immunity and safety of a genetically modified influenza virus vaccine.

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Rafael Polidoro Alves Barbosa

Full Text Available Recombinant influenza viruses are promising viral platforms to be used as antigen delivery vectors. To this aim, one of the most promising approaches consists of generating recombinant viruses harboring partially truncated neuraminidase (NA segments. To date, all studies have pointed to safety and usefulness of this viral platform. However, some aspects of the inflammatory and immune responses triggered by those recombinant viruses and their safety to immunocompromised hosts remained to be elucidated. In the present study, we generated a recombinant influenza virus harboring a truncated NA segment (vNA-Δ and evaluated the innate and inflammatory responses and the safety of this recombinant virus in wild type or knock-out (KO mice with impaired innate (Myd88 -/- or acquired (RAG -/- immune responses. Infection using truncated neuraminidase influenza virus was harmless regarding lung and systemic inflammatory response in wild type mice and was highly attenuated in KO mice. We also demonstrated that vNA-Δ infection does not induce unbalanced cytokine production that strongly contributes to lung damage in infected mice. In addition, the recombinant influenza virus was able to trigger both local and systemic virus-specific humoral and CD8+ T cellular immune responses which protected immunized mice against the challenge with a lethal dose of homologous A/PR8/34 influenza virus. Taken together, our findings suggest and reinforce the safety of using NA deleted influenza viruses as antigen delivery vectors against human or veterinary pathogens.

Parental response to severe or lethal prenatal diagnosis

DEFF Research Database (Denmark)

Lou, Stina; Jensen, Lotte Groth; Petersen, Olav Bjørn

2017-01-01

Objective A severe or lethal prenatal diagnosis places great demands on prospective parents, who face choices of far-reaching consequences, such as continuing or terminating the pregnancy. How best to support these parents is a clinical challenge. This systematic review aimed to identify and synt......Objective A severe or lethal prenatal diagnosis places great demands on prospective parents, who face choices of far-reaching consequences, such as continuing or terminating the pregnancy. How best to support these parents is a clinical challenge. This systematic review aimed to identify...... and synthesize the qualitative evidence regarding prospective parents’ responses to such prenatal diagnoses. Methods Following PRISMA guidelines, four databases were systematically searched and 28 studies met the inclusion criteria. Thematic analysis guided data extraction and synthesis of findings. The CERQual....... Prospective parents who continued the pregnancy wished to be acknowledged as parents, and engaged in planning to obtain a sense of meaning and control. Selective disclosure and concerns about negative responses were issues both for the parents who terminated and those who continued a pregnancy. Conclusion...

Genetic susceptibility to and presence of endogenous avian leukosis viruses impose no significant impact on survival days of chickens challenged with very virulent plus Marek's disease virus

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Chicks of distinct genotypes at the tumor virus B locus (TVB) in combination with presence or absence of endogenous avian leukosis virus ev21 gene in their genomes were examined for survival day patterns after challenge with very virulent plus Marek’s disease virus (vv+MDV) in three consecutive tria...

Atypical myxomatosis--virus isolation, experimental infection of rabbits and restriction endonuclease analysis of the isolate.

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Psikal, I; Smíd, B; Rodák, L; Valícek, L; Bendová, J

2003-08-01

Atypical form of myxomatosis, which caused non-lethal and clinically mild disease in domestic rabbits 1 month after immunization with a commercially available vaccine MXT, is described. The isolated myxoma virus designated as Litovel 2 (Li-2) did not induce systemic disease following subcutaneous and intradermal applications in susceptible experimental rabbits but led to the immune response demonstrated by ELISA. No severe disease was induced in those Li-2 inoculated rabbits by challenge with the virulent strains Lausanne (Lu) or Sanar (SA), while the control animals showed nodular form of myxomatosis with lethal course of the illness. Restriction fragment length polymorphism (RFLP) of genomic DNA with KpnI and BamHI endonucleases was used for genetic characterization of the Li-2 isolate, the vaccine strain MXT and both virulent strains Lu and SA, respectively. In general, RFLP analysis has shown to be informative for inferring genetic relatedness between myxoma viruses. Based on restriction endonuclease DNA fragment size distribution, it was evident that the pathogenic strain SA is genetically related to the reference strain Lu and the isolate Li-2 is more related, but not identical, to the vaccination strain MXT.

Genotype I of Japanese Encephalitis Virus Virus-like Particles Elicit Sterilizing Immunity against Genotype I and III Viral Challenge in Swine.

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Fan, Yi-Chin; Chen, Jo-Mei; Lin, Jen-Wei; Chen, Yi-Ying; Wu, Guan-Hong; Su, Kuan-Hsuan; Chiou, Ming-Tang; Wu, Shang-Rung; Yin, Ji-Hang; Liao, Jiunn-Wang; Chang, Gwong-Jen J; Chiou, Shyan-Song

2018-05-10

Swine are a critical amplifying host involved in human Japanese encephalitis (JE) outbreaks. Cross-genotypic immunogenicity and sterile protection are important for the current genotype III (GIII) virus-derived vaccines in swine, especially now that emerging genotype I (GI) JE virus (JEV) has replaced GIII virus as the dominant strain. Herein, we aimed to develop a system to generate GI JEV virus-like particles (VLPs) and evaluate the immunogenicity and protection of the GI vaccine candidate in mice and specific pathogen-free swine. A CHO-heparan sulfate-deficient (CHO-HS(-)) cell clone, named 51-10 clone, stably expressing GI-JEV VLP was selected and continually secreted GI VLPs without signs of cell fusion. 51-10 VLPs formed a homogeneously empty-particle morphology and exhibited similar antigenic activity as GI virus. GI VLP-immunized mice showed balanced cross-neutralizing antibody titers against GI to GIV viruses (50% focus-reduction micro-neutralization assay titers 71 to 240) as well as potent protection against GI or GIII virus infection. GI VLP-immunized swine challenged with GI or GIII viruses showed no fever, viremia, or viral RNA in tonsils, lymph nodes, and brains as compared with phosphate buffered saline-immunized swine. We thus conclude GI VLPs can provide sterile protection against GI and GIII viruses in swine.

Deliberate reduction of hemagglutinin and neuraminidase expression of influenza virus leads to an ultraprotective live vaccine in mice.

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Yang, Chen; Skiena, Steven; Futcher, Bruce; Mueller, Steffen; Wimmer, Eckard

2013-06-04

A long-held dogma posits that strong presentation to the immune system of the dominant influenza virus glycoprotein antigens neuraminidase (NA) and hemagglutinin (HA) is paramount for inducing protective immunity against influenza virus infection. We have deliberately violated this dogma by constructing a recombinant influenza virus strain of A/PR8/34 (H1N1) in which expression of NA and HA genes was suppressed. We down-regulated NA and HA expression by recoding the respective genes with suboptimal codon pair bias, thereby introducing hundreds of nucleotide changes while preserving their codon use and protein sequence. The variants PR8-NA(Min), PR8-HA(Min), and PR8-(NA+HA)(Min) (Min, minimal expression) were used to assess the contribution of reduced glycoprotein expression to growth in tissue culture and pathogenesis in BALB/c mice. All three variants proliferated in Madin-Darby canine kidney cells to nearly the degree as WT PR8. In mice, however, they expressed explicit attenuation phenotypes, as revealed by their LD50 values: PR8, 32 plaque-forming units (PFU); HA(Min), 1.7 × 10(3) PFU; NA(Min), 2.4 × 10(5) PFU; (NA+HA)(Min), ≥3.16 × 10(6) PFU. Remarkably, (NA+HA)(Min) was attenuated >100,000-fold, with NA(Min) the major contributor to attenuation. In vaccinated mice (NA+HA)(Min) was highly effective in providing long-lasting protective immunity against lethal WT challenge at a median protective dose (PD50) of 2.4 PFU. Moreover, at a PD50 of only 147 or 237, (NA+HA)(Min) conferred protection against heterologous lethal challenges with two mouse-adapted H3N2 viruses. We conclude that the suppression of HA and NA is a unique strategy in live vaccine development.

An attenuated herpes simplex virus type 1 (HSV1 encoding the HIV-1 Tat protein protects mice from a deadly mucosal HSV1 challenge.

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Mariaconcetta Sicurella

Full Text Available Herpes simplex virus types 1 and 2 (HSV1 and HSV2 are common infectious agents in both industrialized and developing countries. They cause recurrent asymptomatic and/or symptomatic infections, and life-threatening diseases and death in newborns and immunocompromised patients. Current treatment for HSV relies on antiviral medications, which can halt the symptomatic diseases but cannot prevent the shedding that occurs in asymptomatic patients or, consequently, the spread of the viruses. Therefore, prevention rather than treatment of HSV infections has long been an area of intense research, but thus far effective anti-HSV vaccines still remain elusive. One of the key hurdles to overcome in anti-HSV vaccine development is the identification and effective use of strategies that promote the emergence of Th1-type immune responses against a wide range of epitopes involved in the control of viral replication. Since the HIV1 Tat protein has several immunomodulatory activities and increases CTL recognition of dominant and subdominant epitopes of heterologous antigens, we generated and assayed a recombinant attenuated replication-competent HSV1 vector containing the tat gene (HSV1-Tat. In this proof-of-concept study we show that immunization with this vector conferred protection in 100% of mice challenged intravaginally with a lethal dose of wild-type HSV1. We demonstrate that the presence of Tat within the recombinant virus increased and broadened Th1-like and CTL responses against HSV-derived T-cell epitopes and elicited in most immunized mice detectable IgG responses. In sharp contrast, a similarly attenuated HSV1 recombinant vector without Tat (HSV1-LacZ, induced low and different T cell responses, no measurable antibody responses and did not protect mice against the wild-type HSV1 challenge. These findings strongly suggest that recombinant HSV1 vectors expressing Tat merit further investigation for their potential to prevent and/or contain HSV1

An attenuated herpes simplex virus type 1 (HSV1) encoding the HIV-1 Tat protein protects mice from a deadly mucosal HSV1 challenge.

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Sicurella, Mariaconcetta; Nicoli, Francesco; Gallerani, Eleonora; Volpi, Ilaria; Berto, Elena; Finessi, Valentina; Destro, Federica; Manservigi, Roberto; Cafaro, Aurelio; Ensoli, Barbara; Caputo, Antonella; Gavioli, Riccardo; Marconi, Peggy C

2014-01-01

Herpes simplex virus types 1 and 2 (HSV1 and HSV2) are common infectious agents in both industrialized and developing countries. They cause recurrent asymptomatic and/or symptomatic infections, and life-threatening diseases and death in newborns and immunocompromised patients. Current treatment for HSV relies on antiviral medications, which can halt the symptomatic diseases but cannot prevent the shedding that occurs in asymptomatic patients or, consequently, the spread of the viruses. Therefore, prevention rather than treatment of HSV infections has long been an area of intense research, but thus far effective anti-HSV vaccines still remain elusive. One of the key hurdles to overcome in anti-HSV vaccine development is the identification and effective use of strategies that promote the emergence of Th1-type immune responses against a wide range of epitopes involved in the control of viral replication. Since the HIV1 Tat protein has several immunomodulatory activities and increases CTL recognition of dominant and subdominant epitopes of heterologous antigens, we generated and assayed a recombinant attenuated replication-competent HSV1 vector containing the tat gene (HSV1-Tat). In this proof-of-concept study we show that immunization with this vector conferred protection in 100% of mice challenged intravaginally with a lethal dose of wild-type HSV1. We demonstrate that the presence of Tat within the recombinant virus increased and broadened Th1-like and CTL responses against HSV-derived T-cell epitopes and elicited in most immunized mice detectable IgG responses. In sharp contrast, a similarly attenuated HSV1 recombinant vector without Tat (HSV1-LacZ), induced low and different T cell responses, no measurable antibody responses and did not protect mice against the wild-type HSV1 challenge. These findings strongly suggest that recombinant HSV1 vectors expressing Tat merit further investigation for their potential to prevent and/or contain HSV1 infection and

Alpha-beta T cells provide protection against lethal encephalitis in the murine model of VEEV infection

International Nuclear Information System (INIS)

Paessler, Slobodan; Yun, Nadezhda E.; Judy, Barbara M.; Dziuba, Natallia; Zacks, Michele A.; Grund, Anna H.; Frolov, Ilya; Campbell, Gerald A.; Weaver, Scott C.; Estes, D. Mark

2007-01-01

We evaluated the safety and immunogenicity of a chimeric alphavirus vaccine candidate in mice with selective immunodeficiencies. This vaccine candidate was highly attenuated in mice with deficiencies in the B and T cell compartments, as well as in mice with deficient gamma-interferon responsiveness. However, the level of protection varied among the strains tested. Wild type mice were protected against lethal VEEV challenge. In contrast, alpha/beta (αβ) TCR-deficient mice developed lethal encephalitis following VEEV challenge, while mice deficient in gamma/delta (γδ) T cells were protected. Surprisingly, the vaccine potency was diminished by 50% in animals lacking interferon-gamma receptor alpha chain (R1)-chain and a minority of vaccinated immunoglobulin heavy chain-deficient (μMT) mice survived challenge, which suggests that neutralizing antibody may not be absolutely required for protection. Prolonged replication of encephalitic VEEV in the brain of pre-immunized mice is not lethal and adoptive transfer experiments indicate that CD3 + T cells are required for protection

In Vivo Production of Monoclonal Antibodies by Gene Transfer via Electroporation Protects against Lethal Influenza and Ebola Infections

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Chasity D. Andrews

2017-12-01

Full Text Available Monoclonal antibodies (mAbs have wide clinical utility, but global access is limited by high costs and impracticalities associated with repeated passive administration. Here, we describe an optimized electroporation-based DNA gene transfer platform technology that can be utilized for production of functional mAbs in vivo, with the potential to reduce costs and administration burdens. We demonstrate that multiple mAbs can be simultaneously expressed at protective concentrations for a protracted period of time using DNA doses and electroporation conditions that are feasible clinically. The expressed mAbs could also protect mice against lethal influenza or Ebola virus challenges. Our findings suggest that this DNA gene transfer platform technology could be a game-changing advance that expands access to effective mAb therapeutics globally.

Histopathological effects of lethal and sub-lethal concentrations of ...

African Journals Online (AJOL)

The histopathological effects of lethal and sub-lethal concentrations of glyphosate on African catfish Clarias gariepinus were investigated. C. gariepinus juveniles were assessed in a static renewal bioassay for 96 hours (acute toxicity) and 28 days (chronic toxicity) using varying concentrations (0.0 mg/l 20.0 mg/l, 30.0 mg/l, ...

Memory T Cells Generated by Prior Exposure to Influenza Cross React with the Novel H7N9 Influenza Virus and Confer Protective Heterosubtypic Immunity

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McMaster, Sean R.; Gabbard, Jon D.; Koutsonanos, Dimitris G.; Compans, Richard W.; Tripp, Ralph A.; Tompkins, S. Mark; Kohlmeier, Jacob E.

2015-01-01

Influenza virus is a source of significant health and economic burden from yearly epidemics and sporadic pandemics. Given the potential for the emerging H7N9 influenza virus to cause severe respiratory infections and the lack of exposure to H7 and N9 influenza viruses in the human population, we aimed to quantify the H7N9 cross-reactive memory T cell reservoir in humans and mice previously exposed to common circulating influenza viruses. We identified significant cross-reactive T cell populations in humans and mice; we also found that cross-reactive memory T cells afforded heterosubtypic protection by reducing morbidity and mortality upon lethal H7N9 challenge. In context with our observation that PR8-primed mice have limited humoral cross-reactivity with H7N9, our data suggest protection from H7N9 challenge is indeed mediated by cross-reactive T cell populations established upon previous priming with another influenza virus. Thus, pre-existing cross-reactive memory T cells may limit disease severity in the event of an H7N9 influenza virus pandemic. PMID:25671696

Memory T cells generated by prior exposure to influenza cross react with the novel H7N9 influenza virus and confer protective heterosubtypic immunity.

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Sean R McMaster

Full Text Available Influenza virus is a source of significant health and economic burden from yearly epidemics and sporadic pandemics. Given the potential for the emerging H7N9 influenza virus to cause severe respiratory infections and the lack of exposure to H7 and N9 influenza viruses in the human population, we aimed to quantify the H7N9 cross-reactive memory T cell reservoir in humans and mice previously exposed to common circulating influenza viruses. We identified significant cross-reactive T cell populations in humans and mice; we also found that cross-reactive memory T cells afforded heterosubtypic protection by reducing morbidity and mortality upon lethal H7N9 challenge. In context with our observation that PR8-primed mice have limited humoral cross-reactivity with H7N9, our data suggest protection from H7N9 challenge is indeed mediated by cross-reactive T cell populations established upon previous priming with another influenza virus. Thus, pre-existing cross-reactive memory T cells may limit disease severity in the event of an H7N9 influenza virus pandemic.

Oral intake of Lactobacillus rhamnosus M21 enhances the survival rate of mice lethally infected with influenza virus.

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Song, Jeong Ah; Kim, Hee Joo; Hong, Seong Keun; Lee, Dong Hoon; Lee, Sang Won; Song, Chang Seon; Kim, Ki Taek; Choi, In Soo; Lee, Joong Bok; Park, Seung Yong

2016-02-01

Influenza viruses cause acute respiratory disease. Because of the high genetic variability of viruses, effective vaccines and antiviral agents are limited. Considering the fact that the site of influenza virus entry is the mucosa of the upper respiratory tract, probiotics that can enhance mucosal immunity as well as systemic immunity could be an important source of treatment against influenza infection. Mice were fed with Lactobacillus rhamnosus M21 or skim milk and were challenged with influenza virus. The resulting survival rate, lung inflammation, and changes in the cytokine and secretory immunoglobulin A (sIgA) levels were examined. Because of infection (influenza virus), all the mice in the control group and 60% of the mice in the L. rhamnosus M21 group died; however, the remaining 40% of the mice fed with L. rhamnosus M21 survived the infection. Pneumonia was severe in the control group but moderate in the group treated with L. rhamnosus M21. Although there were no significant changes in the proinflammatory cytokines in the lung lysates of mice collected from both groups, levels of interferon-γ and interleukin-2, which are representative cytokines of type I helper T cells, were significantly increased in the L. rhamnosus M21-treated group. An increase in sIgA as well as the diminution of inflammatory cells in bronchoalveolar lavage fluid was also observed in the L. rhamnosus M21-treated group. These results demonstrate that orally administered L. rhamnosus M21 activates humoral as well as cellular immune responses, conferring increased resistance to the host against influenza virus infection. Copyright © 2014. Published by Elsevier B.V.

Effect of priming with H1N1 influenza viruses of variable antigenic distances on challenge with 2009 pandemic H1N1 virus.

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O'Donnell, Christopher D; Wright, Amber; Vogel, Leatrice N; Wei, Chih-Jen; Nabel, Gary J; Subbarao, Kanta

2012-08-01

Compared to seasonal influenza viruses, the 2009 pandemic H1N1 (pH1N1) virus caused greater morbidity and mortality in children and young adults. People over 60 years of age showed a higher prevalence of cross-reactive pH1N1 antibodies, suggesting that they were previously exposed to an influenza virus or vaccine that was antigenically related to the pH1N1 virus. To define the basis for this cross-reactivity, ferrets were infected with H1N1 viruses of variable antigenic distance that circulated during different decades from the 1930s (Alaska/35), 1940s (Fort Monmouth/47), 1950s (Fort Warren/50), and 1990s (New Caledonia/99) and challenged with 2009 pH1N1 virus 6 weeks later. Ferrets primed with the homologous CA/09 or New Jersey/76 (NJ/76) virus served as a positive control, while the negative control was an influenza B virus that should not cross-protect against influenza A virus infection. Significant protection against challenge virus replication in the respiratory tract was observed in ferrets primed with AK/35, FM/47, and NJ/76; FW/50-primed ferrets showed reduced protection, and NC/99-primed ferrets were not protected. The hemagglutinins (HAs) of AK/35, FM/47, and FW/50 differ in the presence of glycosylation sites. We found that the loss of protective efficacy observed with FW/50 was associated with the presence of a specific glycosylation site. Our results suggest that changes in the HA occurred between 1947 and 1950, such that prior infection could no longer protect against 2009 pH1N1 infection. This provides a mechanistic understanding of the nature of serological cross-protection observed in people over 60 years of age during the 2009 H1N1 pandemic.

Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

OpenAIRE

Kandadi, Machender R; Yu, Xuejun; Frankel, Arthur E; Ren, Jun

2012-01-01

Abstract Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT) and cardiac-specific catalase overexpression mice were challenged...

Possibility and challenges of conversion of current virus species names to Linnaean binomials

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Thomas, Postler; Clawson, Anna N.; Amarasinghe, Gaya K.; Basler, Christopher F.; Bavari, Sina; Benko, Maria; Blasdell, Kim R.; Briese, Thomas; Buchmeier, Michael J.; Bukreyev, Alexander; Calisher, Charles H.; Chandran, Kartik; Charrel, Remi; Clegg, Christopher S.; Collins, Peter L.; De la Torre, Juan Carlos; DeRisi, Joseph L.; Dietzgen, Ralf G.; Dolnik, Olga; Durrwald, Ralf; Dye, John M.; Easton, Andrew J.; Emonet, Sebastian; Formenty, Pierre; Fouchier, Ron A. M.; Ghedin, Elodie; Gonzalez, Jean-Paul; Harrach, Balazs; Hewson, Roger; Horie, Masayuki; Jiang, Daohong; Kobinger, Gary P.; Kondo, Hideki; Kropinski, Andrew; Krupovic, Mart; Kurath, Gael; Lamb, Robert A.; Leroy, Eric M.; Lukashevich, Igor S.; Maisner, Andrea; Mushegian, Arcady; Netesov, Sergey V.; Nowotny, Norbert; Patterson, Jean L.; Payne, Susan L.; Paweska, Janusz T.; Peters, C.J.; Radoshitzky, Sheli; Rima, Bertus K.; Romanowski, Victor; Rubbenstroth, Dennis; Sabanadzovic, Sead; Sanfacon, Helene; Salvato , Maria; Schwemmle, Martin; Smither, Sophie J.; Stenglein, Mark; Stone, D.M.; Takada , Ayato; Tesh, Robert B.; Tomonaga, Keizo; Tordo, N.; Towner, Jonathan S.; Vasilakis, Nikos; Volchkov, Victor E.; Jensen, Victoria; Walker, Peter J.; Wang, Lin-Fa; Varsani, Arvind; Whitfield , Anna E.; Zerbini, Francisco Murilo; Kuhn, Jens H.

2017-01-01

Botanical, mycological, zoological, and prokaryotic species names follow the Linnaean format, consisting of an italicized Latinized binomen with a capitalized genus name and a lower case species epithet (e.g., Homo sapiens). Virus species names, however, do not follow a uniform format, and, even when binomial, are not Linnaean in style. In this thought exercise, we attempted to convert all currently official names of species included in the virus family Arenaviridae and the virus order Mononegavirales to Linnaean binomials, and to identify and address associated challenges and concerns. Surprisingly, this endeavor was not as complicated or time-consuming as even the authors of this article expected when conceiving the experiment.

Ability of herpes simplex virus vectors to boost immune responses to DNA vectors and to protect against challenge by simian immunodeficiency virus

International Nuclear Information System (INIS)

Kaur, Amitinder; Sanford, Hannah B.; Garry, Deirdre; Lang, Sabine; Klumpp, Sherry A.; Watanabe, Daisuke; Bronson, Roderick T.; Lifson, Jeffrey D.; Rosati, Margherita; Pavlakis, George N.; Felber, Barbara K.; Knipe, David M.; Desrosiers, Ronald C.

2007-01-01

The immunogenicity and protective capacity of replication-defective herpes simplex virus (HSV) vector-based vaccines were examined in rhesus macaques. Three macaques were inoculated with recombinant HSV vectors expressing Gag, Env, and a Tat-Rev-Nef fusion protein of simian immunodeficiency virus (SIV). Three other macaques were primed with recombinant DNA vectors expressing Gag, Env, and a Pol-Tat-Nef-Vif fusion protein prior to boosting with the HSV vectors. Robust anti-Gag and anti-Env cellular responses were detected in all six macaques. Following intravenous challenge with wild-type, cloned SIV239, peak and 12-week plasma viremia levels were significantly lower in vaccinated compared to control macaques. Plasma SIV RNA in vaccinated macaques was inversely correlated with anti-Rev ELISPOT responses on the day of challenge (P value < 0.05), anti-Tat ELISPOT responses at 2 weeks post challenge (P value < 0.05) and peak neutralizing antibody titers pre-challenge (P value 0.06). These findings support continued study of recombinant herpesviruses as a vaccine approach for AIDS

VSVΔG/EBOV GP-induced innate protection enhances natural killer cell activity to increase survival in a lethal mouse adapted Ebola virus infection.

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Williams, Kinola J N; Qiu, Xiangguo; Fernando, Lisa; Jones, Steven M; Alimonti, Judie B

2015-02-01

Members of the species Zaire ebolavirus cause severe hemorrhagic fever with up to a 90% mortality rate in humans. The VSVΔG/EBOV GP vaccine has provided 100% protection in the mouse, guinea pig, and nonhuman primate (NHP) models, and has also been utilized as a post-exposure therapeutic to protect mice, guinea pigs, and NHPs from a lethal challenge of Ebola virus (EBOV). EBOV infection causes rapid mortality in human and animal models, with death occurring as early as 6 days after infection, suggesting a vital role for the innate immune system to control the infection before cells of the adaptive immune system can assume control. Natural killer (NK) cells are the predominant cell of the innate immune response, which has been shown to expand with VSVΔG/EBOV GP treatment. In the current study, an in vivo mouse model of the VSVΔG/EBOV GP post-exposure treatment was used for a mouse adapted (MA)-EBOV infection, to determine the putative VSVΔG/EBOV GP-induced protective mechanism of NK cells. NK depletion studies demonstrated that mice with NK cells survive longer in a MA-EBOV infection, which is further enhanced with VSVΔG/EBOV GP treatment. NK cell mediated cytotoxicity and IFN-γ secretion was significantly higher with VSVΔG/EBOV GP treatment. Cell mediated cytotoxicity assays and perforin knockout mice experiments suggest that there are perforin-dependent and -independent mechanisms involved. Together, these data suggest that NK cells play an important role in VSVΔG/EBOV GP-induced protection of EBOV by increasing NK cytotoxicity, and IFN-γ secretion.

Effects of Helicobacter pylori infection on common lethal factors for hepatitis B virus-related cirrhosis

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LI Yuling

2015-09-01

Full Text Available ObjectiveTo study the relationship between Helicobacter pylori (H. pylori infection and common lethal factors for hepatitis B virus-related cirrhosis (HBC. MethodsA total of 235 patients with HBC who were admitted to our hospitals from October 2008 to October 2014 were retrospectively analyzed. The infection rate of H. pylori in those patients was calculated. In the 155 patients with esophagogastric varices and 97 patients with portal hypertensive gastropathy (PHG, the infection rate of H. pylori was compared between those with different degrees of esophagogastric varices or PHG. In the 32 patients whose blood ammonia was determined, the level of blood ammonia was compared between H. pylori-positive and -negative groups. Between-group comparison of continuous data was performed by t test and analysis of variance, and between-group comparison of categorical data was performed by χ2 test. ResultsThe infection rate of H. pylori in the 235 patients with HBC was 80.85% (190/235. In the 155 patients with esophagogastric varices, who had tortuous serpentine uplift or bead-like changes of esophageal varices and tumor-like changes (with or without gastric erosion of gastric varices visible under endoscopy, there was significant difference in infection rate of H. pylori between patients with mild, moderate, and severe varices (50.55% (46/91 vs 43.59% (17/39 vs 76% (19/25, χ2=6.913, P＜0.05. In the 97 patients with PHG, who had snake skin-like changes, cherry red spots, scarlet rash, and erosion bleeding of gastric mucosa visible under endoscopy, there was significant difference in infection rate of H. pylori between patients with mild and severe PHG (43.33% (26/60 vs 67.57% (25/37, χ2=5.391, P＜005.In patients whose blood ammonia was determined, patients in H. pylori-positive group had a significantly higher average concentration of blood ammonia than those in H. pylori-negative group (62.76±13.43 vs 47.20±12.51 μmol/L, t= 3.39, P＜0

Physician use of updated anti-virus software in a tertiary Nigerian ...

African Journals Online (AJOL)

While physicians are becoming increasingly dependent on computers and the internet, highly lethal malware continue to be loaded into cyberspace. We sought to assess the proportion of ... producers and anti-virus software developers. Keywords: Anti-virus software; Computer security; Updates; Physicians; Nigeria ...

CD4 T cell-mediated protection from lethal influenza: perforin and antibody-mediated mechanisms give a one-two punch.

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Brown, Deborah M; Dilzer, Allison M; Meents, Dana L; Swain, Susan L

2006-09-01

The mechanisms whereby CD4 T cells contribute to the protective response against lethal influenza infection remain poorly characterized. To define the role of CD4 cells in protection against a highly pathogenic strain of influenza, virus-specific TCR transgenic CD4 effectors were generated in vitro and transferred into mice given lethal influenza infection. Primed CD4 effectors conferred protection against lethal infection over a broad range of viral dose. The protection mediated by CD4 effectors did not require IFN-gamma or host T cells, but did result in increased anti-influenza Ab titers compared with untreated controls. Further studies indicated that CD4-mediated protection at high doses of influenza required B cells, and that passive transfer of anti-influenza immune serum was therapeutic in B cell-deficient mice, but only when CD4 effectors were present. Primed CD4 cells also acquired perforin (Pfn)-mediated cytolytic activity during effector generation, suggesting a second mechanism used by CD4 cells to confer protection. Pfn-deficient CD4 effectors were less able to promote survival in intact BALB/c mice and were unable to provide protection in B cell-deficient mice, indicating that Ab-independent protection by CD4 effectors requires Pfn. Therefore, CD4 effectors mediate protection to lethal influenza through at least two mechanisms: Pfn-mediated cytotoxicity early in the response promoted survival independently of Ab production, whereas CD4-driven B cell responses resulted in high titer Abs that neutralized remaining virus.

Ebola Virus Disease: A Review of Its Past and Present.

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Murray, Michael J

2015-09-01

Ebola virus, the virus responsible for Ebola virus disease, has spawned several epidemics during the past 38 years. In 2014, an Ebola epidemic spread from Africa to other continents, becoming a pandemic. The virus's relatively unique structure, its infectivity and lethality, the difficulty in stopping its spread, and the lack of an effective treatment captured the world's attention. This article provides a brief review of the known history of Ebola virus disease, its etiology, epidemiology, and pathophysiology and a review of the limited information on managing patients with Ebola virus disease.

Immune Protection against Lethal Fungal-Bacterial Intra-Abdominal Infections

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Lilly, Elizabeth A.; Ikeh, Melanie; Nash, Evelyn E.; Fidel, Paul L.

2018-01-01

ABSTRACT Polymicrobial intra-abdominal infections (IAIs) are clinically prevalent and cause significant morbidity and mortality, especially those involving fungi. Our laboratory developed a mouse model of IAI and demonstrated that intraperitoneal inoculation with Candida albicans or other virulent non-albicans Candida (NAC) species plus Staphylococcus aureus resulted in 70 to 80% mortality in 48 to 72 h due to robust local and systemic inflammation (sepsis). Surprisingly, inoculation with Candida dubliniensis or Candida glabrata with S. aureus resulted in minimal mortality, and rechallenge of these mice with lethal C. albicans/S. aureus (i.e., coninfection) resulted in >90% protection. The purpose of this study was to define requirements for C. dubliniensis/S. aureus-mediated protection and interrogate the mechanism of the protective response. Protection was conferred by C. dubliniensis alone or by killed C. dubliniensis plus live S. aureus. S. aureus alone was not protective, and killed S. aureus compromised C. dubliniensis-induced protection. C. dubliniensis/S. aureus also protected against lethal challenge by NAC plus S. aureus and could protect for a long-term duration (60 days between primary challenge and C. albicans/S. aureus rechallenge). Unexpectedly, mice deficient in T and B cells (Rag-1 knockouts [KO]) survived both the initial C. dubliniensis/S. aureus challenge and the C. albicans/S. aureus rechallenge, indicating that adaptive immunity did not play a role. Similarly, mice depleted of macrophages prior to rechallenge were also protected. In contrast, protection was associated with high numbers of Gr-1hi polymorphonuclear leukocytes (PMNLs) in peritoneal lavage fluid within 4 h of rechallenge, and in vivo depletion of Gr-1+ cells prior to rechallenge abrogated protection. These results suggest that Candida species can induce protection against a lethal C. albicans/S. aureus IAI that is mediated by PMNLs and postulated to be a unique form of

Immune Protection against Lethal Fungal-Bacterial Intra-Abdominal Infections

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Elizabeth A. Lilly

2018-01-01

Full Text Available Polymicrobial intra-abdominal infections (IAIs are clinically prevalent and cause significant morbidity and mortality, especially those involving fungi. Our laboratory developed a mouse model of IAI and demonstrated that intraperitoneal inoculation with Candida albicans or other virulent non-albicans Candida (NAC species plus Staphylococcus aureus resulted in 70 to 80% mortality in 48 to 72 h due to robust local and systemic inflammation (sepsis. Surprisingly, inoculation with Candida dubliniensis or Candida glabrata with S. aureus resulted in minimal mortality, and rechallenge of these mice with lethal C. albicans/S. aureus (i.e., coninfection resulted in >90% protection. The purpose of this study was to define requirements for C. dubliniensis/S. aureus-mediated protection and interrogate the mechanism of the protective response. Protection was conferred by C. dubliniensis alone or by killed C. dubliniensis plus live S. aureus. S. aureus alone was not protective, and killed S. aureus compromised C. dubliniensis-induced protection. C. dubliniensis/S. aureus also protected against lethal challenge by NAC plus S. aureus and could protect for a long-term duration (60 days between primary challenge and C. albicans/S. aureus rechallenge. Unexpectedly, mice deficient in T and B cells (Rag-1 knockouts [KO] survived both the initial C. dubliniensis/S. aureus challenge and the C. albicans/S. aureus rechallenge, indicating that adaptive immunity did not play a role. Similarly, mice depleted of macrophages prior to rechallenge were also protected. In contrast, protection was associated with high numbers of Gr-1hi polymorphonuclear leukocytes (PMNLs in peritoneal lavage fluid within 4 h of rechallenge, and in vivo depletion of Gr-1+ cells prior to rechallenge abrogated protection. These results suggest that Candida species can induce protection against a lethal C. albicans/S. aureus IAI that is mediated by PMNLs and postulated to be a unique form of

Intranasal immunization of baculovirus displayed hemagglutinin confers complete protection against mouse adapted highly pathogenic H7N7 reassortant influenza virus.

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Subaschandrabose Rajesh Kumar

Full Text Available BACKGROUND: Avian influenza A H7N7 virus poses a pandemic threat to human health because of its ability for direct transmission from domestic poultry to humans and from human to human. The wide zoonotic potential of H7N7 combined with an antiviral immunity inhibition similar to pandemic 1918 H1N1 and 2009 H1N1 influenza viruses is disconcerting and increases the risk of a putative H7N7 pandemic in the future, underlining the urgent need for vaccine development against this virus. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we developed a recombinant vaccine by expressing the H7N7-HA protein on the surface of baculovirus (Bac-HA. The protective efficacy of the live Bac-HA vaccine construct was evaluated in a mouse model by challenging mice immunized intranasally (i.n. or subcutaneously (s.c. with high pathogenic mouse adapted H7N7 reassorted strain. Although s.c. injection of live Bac-HA induced higher specific IgG than i.n. immunization, the later resulted in an elevated neutralization titer. Interestingly, 100% protection from the lethal viral challenge was only observed for the mice immunized intranasally with live Bac-HA, whereas no protection was achieved in any other s.c. or i.n. immunized mice groups. In addition, we also observed higher mucosal IgA as well as increased IFN-γ and IL-4 responses in the splenocytes of the surviving mice coupled with a reduced viral titer and diminished histopathological signs in the lungs. CONCLUSION: Our results indicated that protection from high pathogenic H7N7 (NL/219/03 virus requires both mucosal and systemic immune responses in mice. The balance between Th1 and Th2 cytokines is also required for the protection against the H7N7 pathogen. Intranasal administration of live Bac-HA induced all these immune responses and protected the mice from lethal viral challenge. Therefore, live Bac-HA is an effective vaccine candidate against H7N7 viral infections.

Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease

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Xiao-Xin Wu

2015-11-01

Full Text Available Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD in humans and non-human primates (NHPs. Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs, vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirus∆VP30, recombinant cytomegalovirus (CMV-based vaccines, recombinant rabies virus (RABV-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD.

Experimental aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs.

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Twenhafel, N A; Shaia, C I; Bunton, T E; Shamblin, J D; Wollen, S E; Pitt, L M; Sizemore, D R; Ogg, M M; Johnston, S C

2015-01-01

Eight guinea pigs were aerosolized with guinea pig-adapted Zaire ebolavirus (variant: Mayinga) and developed lethal interstitial pneumonia that was distinct from lesions described in guinea pigs challenged subcutaneously, nonhuman primates challenged by the aerosol route, and natural infection in humans. Guinea pigs succumbed with significant pathologic changes primarily restricted to the lungs. Intracytoplasmic inclusion bodies were observed in many alveolar macrophages. Perivasculitis was noted within the lungs. These changes are unlike those of documented subcutaneously challenged guinea pigs and aerosolized filoviral infections in nonhuman primates and human cases. Similar to findings in subcutaneously challenged guinea pigs, there were only mild lesions in the liver and spleen. To our knowledge, this is the first report of aerosol challenge of guinea pigs with guinea pig-adapted Zaire ebolavirus (variant: Mayinga). Before choosing this model for use in aerosolized ebolavirus studies, scientists and pathologists should be aware that aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs. © The Author(s) 2014.

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

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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.

Protective Effect of Dietary Xylitol on Influenza A Virus Infection

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Yin, Sun Young; Kim, Hyoung Jin; Kim, Hong-Jin

2014-01-01

Xylitol has been used as a substitute for sugar to prevent cavity-causing bacteria, and most studies have focused on its benefits in dental care. Meanwhile, the constituents of red ginseng (RG) are known to be effective in ameliorating the symptoms of influenza virus infection when they are administered orally for 14 days. In this study, we investigated the effect of dietary xylitol on influenza A virus infection (H1N1). We designed regimens containing various fractions of RG (RGs: whole extract, water soluble fraction, saponin and polysaccharide) and xylitol, and combination of xylitol with the RG fractions. Mice received the various combinations orally for 5 days prior to lethal influenza A virus infection. Almost all the mice died post challenge when xylitol or RGs were administered separately. Survival was markedly enhanced when xylitol was administered along with RGs, pointing to a synergistic effect. The effect of xylitol plus RG fractions increased with increasing dose of xylitol. Moreover, dietary xylitol along with the RG water soluble fraction significantly reduced lung virus titers after infection. Therefore, we suggest that dietary xylitol is effective in ameliorating influenza-induced symptoms when it is administered with RG fractions, and this protective effect of xylitol should be considered in relation to other diseases. PMID:24392148

Protective effect of dietary xylitol on influenza A virus infection.

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Sun Young Yin

Full Text Available Xylitol has been used as a substitute for sugar to prevent cavity-causing bacteria, and most studies have focused on its benefits in dental care. Meanwhile, the constituents of red ginseng (RG are known to be effective in ameliorating the symptoms of influenza virus infection when they are administered orally for 14 days. In this study, we investigated the effect of dietary xylitol on influenza A virus infection (H1N1. We designed regimens containing various fractions of RG (RGs: whole extract, water soluble fraction, saponin and polysaccharide and xylitol, and combination of xylitol with the RG fractions. Mice received the various combinations orally for 5 days prior to lethal influenza A virus infection. Almost all the mice died post challenge when xylitol or RGs were administered separately. Survival was markedly enhanced when xylitol was administered along with RGs, pointing to a synergistic effect. The effect of xylitol plus RG fractions increased with increasing dose of xylitol. Moreover, dietary xylitol along with the RG water soluble fraction significantly reduced lung virus titers after infection. Therefore, we suggest that dietary xylitol is effective in ameliorating influenza-induced symptoms when it is administered with RG fractions, and this protective effect of xylitol should be considered in relation to other diseases.

A virus-like particle based bivalent vaccine confers dual protection against enterovirus 71 and coxsackievirus A16 infections in mice.

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Ku, Zhiqiang; Liu, Qingwei; Ye, Xiaohua; Cai, Yicun; Wang, Xiaoli; Shi, Jinping; Li, Dapeng; Jin, Xia; An, Wenqi; Huang, Zhong

2014-07-23

Enterovirus 71(EV71) and coxsackievirus A16 (CA16) are responsible for hand, foot and mouth disease which has been prevalent in Asia-Pacific regions, causing significant morbidity and mortality in young children. Co-circulation of and co-infection by both viruses underscores the importance and urgency of developing vaccines against both viruses simultaneously. Here we report the immunogenicity and protective efficacy of a bivalent combination vaccine comprised of EV71 and CA16 virus-like particles (VLPs). We show that monovalent EV71- or CA16-VLPs-elicited serum antibodies exhibited potent neutralization effect on the homotypic virus but little or no effect on the heterotypic one, whereas the antisera against the bivalent vaccine formulation were able to efficiently neutralize both EV71 and CA16, indicating there is no immunological interference between the two antigens with respect to their ability to induce virus-specific neutralizing antibodies. Passive immunization with monovalent VLP vaccines protected mice against a homotypic virus challenge but not heterotypic infection. Surprisingly, antibody-dependent enhancement (ADE) of disease was observed in mice passively transferred with mono-specific anti-CA16 VLP sera and subsequently challenged with EV71. In contrast, the bivalent VLP vaccine conferred full protection against lethal challenge by either EV71 or CA16, thus eliminating the potential of ADE. Taken together, our results demonstrate for the first time that the bivalent VLP approach represents a safe and efficacious vaccine strategy for both EV71 and CA16. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

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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

Simultaneous outbreaks of dengue, chikungunya and Zika virus infections: diagnosis challenge in a returning traveller with nonspecific febrile illness

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E. Moulin

2016-05-01

Full Text Available Zika virus is an emerging flavivirus that is following the path of dengue and chikungunya. The three Aedes-borne viruses cause simultaneous outbreaks with similar clinical manifestations which represents a diagnostic challenge in ill returning travellers. We report the first Zika virus infection case imported to Switzerland and present a diagnostic algorithm.

Centralized Consensus Hemagglutinin Genes Induce Protective Immunity against H1, H3 and H5 Influenza Viruses.

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Richard J Webby

Full Text Available With the exception of the live attenuated influenza vaccine there have been no substantial changes in influenza vaccine strategies since the 1940's. Here we report an alternative vaccine approach that uses Adenovirus-vectored centralized hemagglutinin (HA genes as vaccine antigens. Consensus H1-Con, H3-Con and H5-Con HA genes were computationally derived. Mice were immunized with Ad vaccines expressing the centralized genes individually. Groups of mice were vaccinated with 1 X 1010, 5 X 107 and 1 X 107 virus particles per mouse to represent high, intermediate and low doses, respectively. 100% of the mice that were vaccinated with the high dose vaccine were protected from heterologous lethal challenges within each subtype. In addition to 100% survival, there were no signs of weight loss and disease in 7 out of 8 groups of high dose vaccinated mice. Lower doses of vaccine showed a reduction of protection in a dose-dependent manner. However, even the lowest dose of vaccine provided significant levels of protection against the divergent influenza strains, especially considering the stringency of the challenge virus. In addition, we found that all doses of H5-Con vaccine were capable of providing complete protection against mortality when challenged with lethal doses of all 3 H5N1 influenza strains. This data demonstrates that centralized H1-Con, H3-Con and H5-Con genes can be effectively used to completely protect mice against many diverse strains of influenza. Therefore, we believe that these Ad-vectored centralized genes could be easily translated into new human vaccines.

Ebola virus: bioterrorism for humans

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Pramodkumar Pyarelal Gupta

2015-01-01

Full Text Available Ebola virus disease is a severe, often fatal, zoonotic infection caused by a virus of the Filoviridae family (genus Ebolavirus. Ebola virus (EBOV spreads by human to human transmission through contacts with body fluids from infected patients. Initial stages of EBOV are non-specific which makes the differential diagnosis broad. Here in this review article we focused on to show the details of EBOV, from its first case right up to the possible targets to cure this lethal disease. In this study we have shown the statistical survey, epidemiology, disease ontology, different genes coding for different proteins in EBOV and future aspects of it.

[Comparison of protective properties of the smallpox DNA-vaccine based on the variola virus A30L gene and its variant with modified codon usage].

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Maksiutov, R A; Shchelkunov, S N

2011-01-01

Efficacy of candidate DNA-vaccines based on the variola virus natural gene A30L and artificial gene A30Lopt with modified codon usage, optimized for expression in mammalian cells, was tested. The groups of mice were intracutaneously immunized three times with three-week intervals with candidate DNA-vaccines: pcDNA_A30L or pcDNA_A30Lopt, and in three weeks after the last immunization all mice in the groups were intraperitoneally infected by the ectromelia virus K1 strain in 10 LD50 dose for the estimation of protection. It was shown that the DNA-vaccines based on natural gene A30L and codon-optimized gene A30Lopt elicited virus, thereby neutralizing the antibody response and protected mice from lethal intraperitoneal challenge with the ectromelia virus with lack of statistically significant difference.

[Research progress on ebola virus glycoprotein].

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Ding, Guo-Yong; Wang, Zhi-Yu; Gao, Lu; Jiang, Bao-Fa

2013-03-01

Ebola virus (EBOV) causes outbreaks of a highly lethal hemorrhagic fever in humans and there are no effective therapeutic or prophylactic treatments available. The glycoprotein (GP) of EBOV is a transmembrane envelope protein known to play multiple functions including virus attachment and entry, cell rounding and cytotoxicity, down-regulation of host surface proteins, and enhancement of virus assembly and budding. GP is the primary target of protective immunity and the key target for developing neutralizing antibodies. In this paper, the research progress on genetic structure, pathogenesis and immunogenicity of EBOV GP in the last 5 years is reviewed.

Evaluation of the efficacy and duration of immunity of a canine combination vaccine against virulent parvovirus, infectious canine hepatitis virus, and distemper virus experimental challenges.

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Abdelmagid, Omar Y; Larson, Laurie; Payne, Laurie; Tubbs, Anna; Wasmoen, Terri; Schultz, Ronald

2004-01-01

The results of this study confirmed that dogs vaccinated subcutaneously with a commercially available multivalent vaccine containing modified-live canine distemper virus, canine adenovirus type 2, canine parvovirus type 2b, and canine parainfluenza virus antigens were protected against sequential experimental challenge 55 to 57 months after initial vaccination given at 7 to 8 weeks of age. All 10 vaccinates were protected against clinical diseases and mortality following parvovirus and infectious canine hepatitis experimental infections. All vaccinates were protected against mortality and 90% against clinical disease following distemper challenge. These data support at least a 4-year duration of immunity for these three "core" fractions in the combination vaccine.

Testing of candidate non-lethal sampling methods for detection of Renibacterium salmoninarum in juvenile Chinook salmon Oncorhynchus tshawytscha

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Elliott, Diane G.; McKibben, Constance L.; Conway, Carla M.; Purcell, Maureen K.; Chase, Dorothy M.; Applegate, Lynn M.

2015-01-01

Non-lethal pathogen testing can be a useful tool for fish disease research and management. Our research objectives were to determine if (1) fin clips, gill snips, surface mucus scrapings, blood draws, or kidney biopsies could be obtained non-lethally from 3 to 15 g Chinook salmon Oncorhynchus tshawytscha, (2) non-lethal samples could accurately discriminate between fish exposed to the bacterial kidney disease agent Renibacterium salmoninarum and non-exposed fish, and (3) non-lethal samples could serve as proxies for lethal kidney samples to assess infection intensity. Blood draws and kidney biopsies caused ≥5% post-sampling mortality (Objective 1) and may be appropriate only for larger fish, but the other sample types were non-lethal. Sampling was performed over 21 wk following R. salmoninarum immersion challenge of fish from 2 stocks (Objectives 2 and 3), and nested PCR (nPCR) and real-time quantitative PCR (qPCR) results from candidate non-lethal samples were compared with kidney tissue analysis by nPCR, qPCR, bacteriological culture, enzyme-linked immunosorbent assay (ELISA), fluorescent antibody test (FAT) and histopathology/immunohistochemistry. R. salmoninarum was detected by PCR in >50% of fin, gill, and mucus samples from challenged fish. Mucus qPCR was the only non-lethal assay exhibiting both diagnostic sensitivity and specificity estimates >90% for distinguishing between R. salmoninarum-exposed and non-exposed fish and was the best candidate for use as an alternative to lethal kidney sample testing. Mucus qPCR R. salmoninarum quantity estimates reflected changes in kidney bacterial load estimates, as evidenced by significant positive correlations with kidney R. salmoninaruminfection intensity scores at all sample times and in both fish stocks, and were not significantly impacted by environmentalR. salmoninarum concentrations.

Newcastle disease virus (NDV) recombinants expressing infectious laryngotracheitis virus (ILTV) glycoproteins gB and gD protect chickens against ILTV and NDV challenges.

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Zhao, Wei; Spatz, Stephen; Zhang, Zhenyu; Wen, Guoyuan; Garcia, Maricarmen; Zsak, Laszlo; Yu, Qingzhong

2014-08-01

Infectious laryngotracheitis (ILT) is a highly contagious acute respiratory disease of chickens caused by infectious laryngotracheitis virus (ILTV). The disease is controlled mainly through biosecurity and vaccination with live attenuated strains of ILTV and vectored vaccines based on turkey herpesvirus (HVT) and fowlpox virus (FPV). The current live attenuated vaccines (chicken embryo origin [CEO] and tissue culture origin [TCO]), although effective, can regain virulence, whereas HVT- and FPV-vectored ILTV vaccines are less efficacious than live attenuated vaccines. Therefore, there is a pressing need to develop safer and more efficacious ILTV vaccines. In the present study, we generated Newcastle disease virus (NDV) recombinants, based on the LaSota vaccine strain, expressing glycoproteins B (gB) and D (gD) of ILTV using reverse genetics technology. These recombinant viruses, rLS/ILTV-gB and rLS/ILTV-gD, were slightly attenuated in vivo yet retained growth dynamics, stability, and virus titers in vitro that were similar to those of the parental LaSota virus. Expression of ILTV gB and gD proteins in the recombinant virus-infected cells was detected by immunofluorescence assay. Vaccination of specific-pathogen-free chickens with these recombinant viruses conferred significant protection against virulent ILTV and velogenic NDV challenges. Immunization of commercial broilers with rLS/ILTV-gB provided a level of protection against clinical disease similar to that provided by the live attenuated commercial vaccines, with no decrease in body weight gains. The results of the study suggested that the rLS/ILTV-gB and -gD viruses are safe, stable, and effective bivalent vaccines that can be mass administered via aerosol or drinking water to large chicken populations. This paper describes the development and evaluation of novel bivalent vaccines against chicken infectious laryngotracheitis (ILT) and Newcastle disease (ND), two of the most economically important infectious

Ebola virus. Two-pore channels control Ebola virus host cell entry and are drug targets for disease treatment.

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Sakurai, Yasuteru; Kolokoltsov, Andrey A; Chen, Cheng-Chang; Tidwell, Michael W; Bauta, William E; Klugbauer, Norbert; Grimm, Christian; Wahl-Schott, Christian; Biel, Martin; Davey, Robert A

2015-02-27

Ebola virus causes sporadic outbreaks of lethal hemorrhagic fever in humans, but there is no currently approved therapy. Cells take up Ebola virus by macropinocytosis, followed by trafficking through endosomal vesicles. However, few factors controlling endosomal virus movement are known. Here we find that Ebola virus entry into host cells requires the endosomal calcium channels called two-pore channels (TPCs). Disrupting TPC function by gene knockout, small interfering RNAs, or small-molecule inhibitors halted virus trafficking and prevented infection. Tetrandrine, the most potent small molecule that we tested, inhibited infection of human macrophages, the primary target of Ebola virus in vivo, and also showed therapeutic efficacy in mice. Therefore, TPC proteins play a key role in Ebola virus infection and may be effective targets for antiviral therapy. Copyright © 2015, American Association for the Advancement of Science.

Ebola Virus Infections in Nonhuman Primates Are Temporally Influenced by Glycoprotein Poly-U Editing Site Populations in the Exposure Material

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Trefry, John C.; Wollen, Suzanne E.; Nasar, Farooq; Shamblin, Joshua D.; Kern, Steven J.; Bearss, Jeremy J.; Jefferson, Michelle A.; Chance, Taylor B.; Kugelman, Jeffery R.; Ladner, Jason T.; Honko, Anna N.; Kobs, Dean J.; Wending, Morgan Q.S.; Sabourin, Carol L.; Pratt, William D.; Palacios, Gustavo F.; Pitt, M. Louise M.

2015-01-01

Recent experimentation with the variants of the Ebola virus that differ in the glycoprotein’s poly-uridine site, which dictates the form of glycoprotein produced through a transcriptional stutter, has resulted in questions regarding the pathogenicity and lethality of the stocks used to develop products currently undergoing human clinical trials to combat the disease. In order to address these concerns and prevent the delay of these critical research programs, we designed an experiment that permitted us to intramuscularly challenge statistically significant numbers of naïve and vaccinated cynomolgus macaques with either a 7U or 8U variant of the Ebola virus, Kikwit isolate. In naïve animals, no difference in survivorship was observed; however, there was a significant delay in the disease course between the two groups. Significant differences were also observed in time-of-fever, serum chemistry, and hematology. In vaccinated animals, there was no statistical difference in survivorship between either challenge groups, with two succumbing in the 7U group compared to 1 in the 8U challenge group. In summary, survivorship was not affected, but the Ebola virus disease course in nonhuman primates is temporally influenced by glycoprotein poly-U editing site populations. PMID:26703716

Ebola Virus Infections in Nonhuman Primates Are Temporally Influenced by Glycoprotein Poly-U Editing Site Populations in the Exposure Material

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John C. Trefry

2015-12-01

Full Text Available Recent experimentation with the variants of the Ebola virus that differ in the glycoprotein’s poly-uridine site, which dictates the form of glycoprotein produced through a transcriptional stutter, has resulted in questions regarding the pathogenicity and lethality of the stocks used to develop products currently undergoing human clinical trials to combat the disease. In order to address these concerns and prevent the delay of these critical research programs, we designed an experiment that permitted us to intramuscularly challenge statistically significant numbers of naïve and vaccinated cynomolgus macaques with either a 7U or 8U variant of the Ebola virus, Kikwit isolate. In naïve animals, no difference in survivorship was observed; however, there was a significant delay in the disease course between the two groups. Significant differences were also observed in time-of-fever, serum chemistry, and hematology. In vaccinated animals, there was no statistical difference in survivorship between either challenge groups, with two succumbing in the 7U group compared to 1 in the 8U challenge group. In summary, survivorship was not affected, but the Ebola virus disease course in nonhuman primates is temporally influenced by glycoprotein poly-U editing site populations.

Immune Protection against Lethal Fungal-Bacterial Intra-Abdominal Infections.

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Lilly, Elizabeth A; Ikeh, Melanie; Nash, Evelyn E; Fidel, Paul L; Noverr, Mairi C

2018-01-16

Polymicrobial intra-abdominal infections (IAIs) are clinically prevalent and cause significant morbidity and mortality, especially those involving fungi. Our laboratory developed a mouse model of IAI and demonstrated that intraperitoneal inoculation with Candida albicans or other virulent non- albicans Candida (NAC) species plus Staphylococcus aureus resulted in 70 to 80% mortality in 48 to 72 h due to robust local and systemic inflammation (sepsis). Surprisingly, inoculation with Candida dubliniensis or Candida glabrata with S. aureus resulted in minimal mortality, and rechallenge of these mice with lethal C. albicans / S. aureus (i.e., coninfection) resulted in >90% protection. The purpose of this study was to define requirements for C. dubliniensis / S. aureus -mediated protection and interrogate the mechanism of the protective response. Protection was conferred by C. dubliniensis alone or by killed C. dubliniensis plus live S. aureus S. aureus alone was not protective, and killed S. aureus compromised C. dubliniensis -induced protection. C. dubliniensis / S. aureus also protected against lethal challenge by NAC plus S. aureus and could protect for a long-term duration (60 days between primary challenge and C. albicans/S. aureus rechallenge). Unexpectedly, mice deficient in T and B cells (Rag-1 knockouts [KO]) survived both the initial C. dubliniensis/S. aureus challenge and the C. albicans/S. aureus rechallenge, indicating that adaptive immunity did not play a role. Similarly, mice depleted of macrophages prior to rechallenge were also protected. In contrast, protection was associated with high numbers of Gr-1 hi polymorphonuclear leukocytes (PMNLs) in peritoneal lavage fluid within 4 h of rechallenge, and in vivo depletion of Gr-1 + cells prior to rechallenge abrogated protection. These results suggest that Candida species can induce protection against a lethal C. albicans / S. aureus IAI that is mediated by PMNLs and postulated to be a unique form of

Suicide Lethality: A Concept Analysis.

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DeBastiani, Summer; De Santis, Joseph P

2018-02-01

Suicide is a significant health problem internationally. Those who complete suicide may have different behaviors and risk factors than those who attempt a non-fatal suicide. The purpose of this article is to analyze the concept of suicide lethality and propose a clear definition of the concept through the identification of antecedents, attributes, and consequences. A literature search for articles published in the English language between 1970 and 2016 was conducted using MEDLINE, the Cochrane Library, Pubmed, Psychlit, Ovid, PsycINFO, and Proquest. The bibliographies of all included studies were also reviewed to identify additional relevant citations. A concept analysis was conducted on the literature findings using six stages of Walker and Avant's method. The concept analysis differentiated between suicide, lethality, suicidal behavior, and suicide lethality. Presence of a suicide plan or a written suicide note was not found to be associated with the majority of completed suicides included in the definition of suicide lethality. There are a few scales that measure the lethality of a suicide attempt, but none that attempt to measure the concept of suicide lethality as described in this analysis. Clarifying the concept of suicide lethality encourages awareness of the possibility of different suicidal behaviors associated with different suicide outcomes and will inform the development of future nursing interventions. A clearer definition of the concept of suicide lethality will guide clinical practice, research, and policy development aimed at suicide prevention.

Ebolavirus Vaccines: Progress in the Fight Against Ebola Virus Disease.

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Wu, Xiao-Xin; Yao, Hang-Ping; Wu, Nan-Ping; Gao, Hai-Nv; Wu, Hai-Bo; Jin, Chang-Zhong; Lu, Xiang-Yun; Xie, Tian-Shen; Li, Lan-Juan

2015-01-01

Ebolaviruses are highly infectious pathogens that cause lethal Ebola virus disease (EVD) in humans and non-human primates (NHPs). Due to their high pathogenicity and transmissibility, as well as the potential to be misused as a bioterrorism agent, ebolaviruses would threaten the health of global populations if not controlled. In this review, we describe the origin and structure of ebolaviruses and the development of vaccines from the beginning of the 1980s, including conventional ebolavirus vaccines, DNA vaccines, Ebola virus-like particles (VLPs), vaccinia virus-based vaccines, Venezuelan equine encephalitis virus (VEEV)-like replicon particles, Kunjin virus-based vaccine, recombinant Zaire Ebolavirusx2206;VP30, recombinant cytomegalovirus (CMV)-based vaccines, recombinant rabies virus (RABV)-based vaccines, recombinant paramyxovirus-based vaccines, adenovirus-based vaccines and vesicular stomatitis virus (VSV)-based vaccines. No licensed vaccine or specific treatment is currently available to counteract ebolavirus infection, although DNA plasmids and several viral vector approaches have been evaluated as promising vaccine platforms. These vaccine candidates have been confirmed to be successful in protecting NHPs against lethal infection. Moreover, these vaccine candidates were successfully advanced to clinical trials. The present review provides an update of the current research on Ebola vaccines, with the aim of providing an overview on current prospects in the fight against EVD. © 2015 The Author(s) Published by S. Karger AG, Basel.

Cedar virus: a novel Henipavirus isolated from Australian bats.

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Glenn A Marsh

Full Text Available The genus Henipavirus in the family Paramyxoviridae contains two viruses, Hendra virus (HeV and Nipah virus (NiV for which pteropid bats act as the main natural reservoir. Each virus also causes serious and commonly lethal infection of people as well as various species of domestic animals, however little is known about the associated mechanisms of pathogenesis. Here, we report the isolation and characterization of a new paramyxovirus from pteropid bats, Cedar virus (CedPV, which shares significant features with the known henipaviruses. The genome size (18,162 nt and organization of CedPV is very similar to that of HeV and NiV; its nucleocapsid protein displays antigenic cross-reactivity with henipaviruses; and it uses the same receptor molecule (ephrin-B2 for entry during infection. Preliminary challenge studies with CedPV in ferrets and guinea pigs, both susceptible to infection and disease with known henipaviruses, confirmed virus replication and production of neutralizing antibodies although clinical disease was not observed. In this context, it is interesting to note that the major genetic difference between CedPV and HeV or NiV lies within the coding strategy of the P gene, which is known to play an important role in evading the host innate immune system. Unlike HeV, NiV, and almost all known paramyxoviruses, the CedPV P gene lacks both RNA editing and also the coding capacity for the highly conserved V protein. Preliminary study indicated that CedPV infection of human cells induces a more robust IFN-β response than HeV.

Protection against West Nile virus infection in mice after inoculation with type I interferon-inducing RNA transcripts.

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Miguel Rodríguez-Pulido

Full Text Available West Nile virus (WNV is a neurovirulent single stranded RNA mosquito-borne flavivirus, whose main natural hosts are birds, but it also infects humans and horses. Nowadays, no human vaccine is commercially available and clinical treatment is only supportive. Recently, it has been shown that RNA transcripts, mimicking structural domains in the non-coding regions (NCRs of the foot-and mouth disease virus (FMDV induce a potent IFN response and antiviral activity in transfected cultured cells, and also reduced mice susceptibility to FMDV. By using different transcripts combinations, administration schedules, and infecting routes and doses, we have demonstrated that these FMDV RNA transcripts protect suckling and adult mice against lethal challenge with WNV. The protective activity induced by the transcripts was systemic and dependent on the infection route and dose. These results confirm the antiviral potential of these synthetic RNAs for fighting viruses of different families relevant for human and animal health.

Preventative Vaccines for Zika Virus Outbreak: Preliminary Evaluation

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Eun Kim

2016-11-01

Full Text Available Since it emerged in Brazil in May 2015, the mosquito-borne Zika virus (ZIKV has raised global concern due to its association with a significant rise in the number of infants born with microcephaly and neurological disorders such as Guillain-Barré syndrome. We developed prototype subunit and adenoviral-based Zika vaccines encoding the extracellular portion of the ZIKV envelope gene (E fused to the T4 fibritin foldon trimerization domain (Efl. The subunit vaccine was delivered intradermally through carboxymethyl cellulose microneedle array (MNA. The immunogenicity of these two vaccines, named Ad5.ZIKV-Efl and ZIKV-rEfl, was tested in C57BL/6 mice. Prime/boost immunization regimen was associated with induction of a ZIKV-specific antibody response, which provided neutralizing immunity. Moreover, protection was evaluated in seven-day-old pups after virulent ZIKV intraperitoneal challenge. Pups born to mice immunized with Ad5.ZIKV-Efl were all protected against lethal challenge infection without weight loss or neurological signs, while pups born to dams immunized with MNA-ZIKV-rEfl were partially protected (50%. No protection was seen in pups born to phosphate buffered saline-immunized mice. This study illustrates the preliminary efficacy of the E ZIKV antigen vaccination in controlling ZIKV infectivity, providing a promising candidate vaccine and antigen format for the prevention of Zika virus disease.

Structural Basis for the Binding of the Neutralizing Antibody, 7D11, to the Poxvirus L1 Protein

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2007-08-01

pCR- 7D11-vHC and pCR-7D11- vLC , respectively. Crystallization of the complex between L1 and 7D11-Fab VACV L1 protein was expressed and purified as...2005. Vaccinia virus H3L envelope protein is a major target of neutralizing antibodies in humans and elicits protection against lethal challenge in...D.M., Schmaljohn, C., Schmaljohn, A., 2000. DNA vaccination with vaccinia virus L1R and A33R genes protects mice against a lethal poxvirus challenge

Ebola Virus Altered Innate and Adaptive Immune Response Signalling Pathways: Implications for Novel Therapeutic Approaches.

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Kumar, Anoop

2016-01-01

Ebola virus (EBOV) arise attention for their impressive lethality by the poor immune response and high inflammatory reaction in the patients. It causes a severe hemorrhagic fever with case fatality rates of up to 90%. The mechanism underlying this lethal outcome is poorly understood. In 2014, a major outbreak of Ebola virus spread amongst several African countries, including Leone, Sierra, and Guinea. Although infections only occur frequently in Central Africa, but the virus has the potential to spread globally. Presently, there is no vaccine or treatment is available to counteract Ebola virus infections due to poor understanding of its interaction with the immune system. Accumulating evidence indicates that the virus actively alters both innate and adaptive immune responses and triggers harmful inflammatory responses. In the literature, some reports have shown that alteration of immune signaling pathways could be due to the ability of EBOV to interfere with dendritic cells (DCs), which link innate and adaptive immune responses. On the other hand, some reports have demonstrated that EBOV, VP35 proteins act as interferon antagonists. So, how the Ebola virus altered the innate and adaptive immune response signaling pathways is still an open question for the researcher to be explored. Thus, in this review, I try to summarize the mechanisms of the alteration of innate and adaptive immune response signaling pathways by Ebola virus which will be helpful for designing effective drugs or vaccines against this lethal infection. Further, potential targets, current treatment and novel therapeutic approaches have also been discussed.

Competitive inhibitor of cellular alpha-glucosidases protects mice from lethal dengue virus infection

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Chang, Jinhong; Schul, Wouter; Yip, Andy; Xu, Xiaodong; Guo, Ju-Tao; Block, Timothy M.

2011-01-01

Dengue virus infection causes diseases in people, ranging from the acute febrile illness Dengue fever, to life-threatening Dengue Hemorrhagic Fever/Dengue Shock Syndrome. We previously reported that a host cellular α-glucosidases I and II inhibitor, imino sugar CM-10-18, potently inhibited dengue virus replication in cultured cells, and significantly reduced viremia in dengue virus infected AG129 mice. In this report we show that CM-10-18 also significantly protects mice from death and/or dis...

A Bioprocessed Polysaccharide from Lentinus edodes Mycelia Cultures with Turmeric Protects Chicks from a Lethal Challenge of Salmonella Gallinarum.

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Han, Dalmuri; Lee, Hyung Tae; Lee, June Bong; Kim, Yongbaek; Lee, Sang Jong; Yoon, Jang Won

2017-02-01

Our previous studies demonstrated that a bioprocessed polysaccharide (BPP) isolated from Lentinus edodes mushroom mycelia cultures supplemented with black rice bran can protect mice against Salmonella lipopolysaccharide-induced endotoxemia and reduce the mortality from Salmonella Typhimurium infection through upregulated T-helper 1 immunity. Here, we report that a BPP from L. edodes mushroom mycelia liquid cultures supplemented with turmeric (referred to as BPP-turmeric) alters chicken macrophage responses against avian-adapted Salmonella Gallinarum and protects chicks against a lethal challenge from Salmonella Gallinarum. In vitro analyses revealed that the water extract of BPP-turmeric (i) changed the protein expression or secretion profile of Salmonella Gallinarum, although it was not bactericidal, (ii) reduced the phagocytic activity of the chicken-derived macrophage cell line HD-11 when infected with Salmonella Gallinarum, and (iii) significantly activated the transcription expression of interleukin (IL)-1β, IL-10, tumor necrosis factor α, and inducible nitric oxide synthase in response to various Salmonella infections, whereas it repressed that of IL-4, IL-6, interferon-β, and interferon-γ. We also found that BPP-turmeric (0.1 g/kg of feed) as a feed additive provided significant protection to 1-day-old chicks infected with a lethal dose of Salmonella Gallinarum. Collectively, these results imply that BPP-turmeric contains biologically active component(s) that protect chicks against Salmonella Gallinarum infection, possibly by regulating macrophage immune responses. Further studies are needed to evaluate the potential efficacy of BPP-turmeric as a livestock feed additive for the preharvest control of fowl typhoid or foodborne salmonellosis.

First insights into the protective effects of a recombinant swinepox virus expressing truncated MRP of Streptococcus suis type 2 in mice.

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Huang, Dongyan; Zhu, Haodan; Lin, Huixing; Xu, Jiarong; Lu, Chengping

2012-01-01

To explore the potential of the swinepox virus (SPV) as vector for Streptococcus suis vaccines, a vector system was developed for the construction of a recombinant SPV carrying bacterial genes. Using this system, a recombinant virus expressing truncated muramidase-released protein (MRP) of S. suis type 2 (SS2), designated rSPV-MRP, was produced and identified by PCR, western blotting and immunofluorescence assays. The rSPV-MRP was found to be only slightly attenuated in PK-15 cells, when compared with the wild-type virus. After immunization intramuscularly with rSPV-MRP, SS2 inactive vaccine (positive control), wild-type SPV (negative control) and PBS (blank control) respectively, all CD1 mice were challenged with a lethal dose or a sublethal dose of SS2 highly virulent strain ZY05719. While SS2 inactive vaccine protected all mice, immunization with rSPV-MRP resulted in 60% survival and protected mice against a lethal dose of the highly virulent SS2 strain, compared with the negative control (P MRP had a significantly reduced bacterial burden in all organs examined, compared to negative controls and blank controls (P MRP-vaccinated group were significantly higher (P MRP provided mice with protection from systemic SS2 infection. If SPV recombinants have the potential as S. suis vaccines for the use in pigs has to be evaluated in further studies.

Particle-to-PFU ratio of Ebola virus influences disease course and survival in cynomolgus macaques.

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Alfson, Kendra J; Avena, Laura E; Beadles, Michael W; Staples, Hilary; Nunneley, Jerritt W; Ticer, Anysha; Dick, Edward J; Owston, Michael A; Reed, Christopher; Patterson, Jean L; Carrion, Ricardo; Griffiths, Anthony

2015-07-01

This study addresses the role of Ebola virus (EBOV) specific infectivity in virulence. Filoviruses are highly lethal, enveloped, single-stranded negative-sense RNA viruses that can cause hemorrhagic fever. No approved vaccines or therapies exist for filovirus infections, and infectious virus must be handled in maximum containment. Efficacy testing of countermeasures, in addition to investigations of pathogenicity and immune response, often requires a well-characterized animal model. For EBOV, an obstacle in performing accurate disease modeling is a poor understanding of what constitutes an infectious dose in animal models. One well-recognized consequence of viral passage in cell culture is a change in specific infectivity, often measured as a particle-to-PFU ratio. Here, we report that serial passages of EBOV in cell culture resulted in a decrease in particle-to-PFU ratio. Notably, this correlated with decreased potency in a lethal cynomolgus macaque (Macaca fascicularis) model of infection; animals were infected with the same viral dose as determined by plaque assay, but animals that received more virus particles exhibited increased disease. This suggests that some particles are unable to form a plaque in a cell culture assay but are able to result in lethal disease in vivo. These results have a significant impact on how future studies are designed to model EBOV disease and test countermeasures. Ebola virus (EBOV) can cause severe hemorrhagic disease with a high case-fatality rate, and there are no approved vaccines or therapies. Specific infectivity can be considered the total number of viral particles per PFU, and its impact on disease is poorly understood. In stocks of most mammalian viruses, there are particles that are unable to complete an infectious cycle or unable to cause cell pathology in cultured cells. We asked if these particles cause disease in nonhuman primates by infecting monkeys with equal infectious doses of genetically identical stocks

Protective Effect of Different Anti-Rabies Virus VHH Constructs against Rabies Disease in Mice

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Terryn, Sanne; Francart, Aurélie; Lamoral, Sophie; Hultberg, Anna; Rommelaere, Heidi; Wittelsberger, Angela; Callewaert, Filip; Stohr, Thomas; Meerschaert, Kris; Ottevaere, Ingrid; Stortelers, Catelijne; Vanlandschoot, Peter; Kalai, Michael; Van Gucht, Steven

2014-01-01

Rabies virus causes lethal brain infection in about 61000 people per year. Each year, tens of thousands of people receive anti-rabies prophylaxis with plasma-derived immunoglobulins and vaccine soon after exposure. Anti-rabies immunoglobulins are however expensive and have limited availability. VHH are the smallest antigen-binding functional fragments of camelid heavy chain antibodies, also called Nanobodies. The therapeutic potential of anti-rabies VHH was examined in a mouse model using intranasal challenge with a lethal dose of rabies virus. Anti-rabies VHH were administered directly into the brain or systemically, by intraperitoneal injection, 24 hours after virus challenge. Anti-rabies VHH were able to significantly prolong survival or even completely rescue mice from disease. The therapeutic effect depended on the dose, affinity and brain and plasma half-life of the VHH construct. Increasing the affinity by combining two VHH with a glycine-serine linker into bivalent or biparatopic constructs, increased the neutralizing potency to the picomolar range. Upon direct intracerebral administration, a dose as low as 33 µg of the biparatopic Rab-E8/H7 was still able to establish an anti-rabies effect. The effect of systemic treatment was significantly improved by increasing the half-life of Rab-E8/H7 through linkage with a third VHH targeted against albumin. Intraperitoneal treatment with 1.5 mg (2505 IU, 1 ml) of anti-albumin Rab-E8/H7 prolonged the median survival time from 9 to 15 days and completely rescued 43% of mice. For comparison, intraperitoneal treatment with the highest available dose of human anti-rabies immunoglobulins (65 mg, 111 IU, 1 ml) only prolonged survival by 2 days, without rescue. Overall, the therapeutic benefit seemed well correlated with the time of brain exposure and the plasma half-life of the used VHH construct. These results, together with the ease-of-production and superior thermal stability, render anti-rabies VHH into valuable

Zika Virus: Medical Countermeasure Development Challenges.

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Robert W Malone

2016-03-01

Full Text Available Reports of high rates of primary microcephaly and Guillain-Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs available for Zika virus infection and disease. The Pan American Health Organization (PAHO predicts that Zika virus will continue to spread and eventually reach all countries and territories in the Americas with endemic Aedes mosquitoes. This paper reviews the status of the Zika virus outbreak, including medical countermeasure options, with a focus on how the epidemiology, insect vectors, neuropathology, virology and immunology inform options and strategies available for medical countermeasure development and deployment.Multiple information sources were employed to support the review. These included publically available literature, patents, official communications, English and Lusophone lay press. Online surveys were distributed to physicians in the US, Mexico and Argentina and responses analyzed. Computational epitope analysis as well as infectious disease outbreak modeling and forecasting were implemented. Field observations in Brazil were compiled and interviews conducted with public health officials.

Zika Virus: Medical Countermeasure Development Challenges

Science.gov (United States)

Malone, Robert W.; Homan, Jane; Callahan, Michael V.; Glasspool-Malone, Jill; Damodaran, Lambodhar; Schneider, Adriano De Bernardi; Zimler, Rebecca; Talton, James; Cobb, Ronald R.; Ruzic, Ivan; Smith-Gagen, Julie; Janies, Daniel; Wilson, James

2016-01-01

Introduction Reports of high rates of primary microcephaly and Guillain–Barré syndrome associated with Zika virus infection in French Polynesia and Brazil have raised concerns that the virus circulating in these regions is a rapidly developing neuropathic, teratogenic, emerging infectious public health threat. There are no licensed medical countermeasures (vaccines, therapies or preventive drugs) available for Zika virus infection and disease. The Pan American Health Organization (PAHO) predicts that Zika virus will continue to spread and eventually reach all countries and territories in the Americas with endemic Aedes mosquitoes. This paper reviews the status of the Zika virus outbreak, including medical countermeasure options, with a focus on how the epidemiology, insect vectors, neuropathology, virology and immunology inform options and strategies available for medical countermeasure development and deployment. Methods Multiple information sources were employed to support the review. These included publically available literature, patents, official communications, English and Lusophone lay press. Online surveys were distributed to physicians in the US, Mexico and Argentina and responses analyzed. Computational epitope analysis as well as infectious disease outbreak modeling and forecasting were implemented. Field observations in Brazil were compiled and interviews conducted with public health officials. PMID:26934531

Myxoma virus in the European rabbit: interactions between the virus and its susceptible host.

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Stanford, Marianne M; Werden, Steven J; McFadden, Grant

2007-01-01

Myxoma virus (MV) is a poxvirus that evolved in Sylvilagus lagomorphs, and is the causative agent of myxomatosis in European rabbits (Oryctolagus cuniculus). This virus is not a natural pathogen of O. cuniculus, yet is able to subvert the host rabbit immune system defenses and cause a highly lethal systemic infection. The interaction of MV proteins and the rabbit immune system has been an ideal model to help elucidate host/poxvirus interactions, and has led to a greater understanding of how other poxvirus pathogens are able to cause disease in their respective hosts. This review will examine how MV causes myxomatosis, by examining a selection of the identified immunomodulatory proteins that this virus expresses to subvert the immune and inflammatory pathways of infected rabbit hosts.

Lung Irradiation Increases Mortality After Influenza A Virus Challenge Occurring Late After Exposure

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Manning, Casey M. [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Johnston, Carl J. [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Department of Pediatrics, University of Rochester Medical Center, Rochester, New York (United States); Reed, Christina K. [Department of Pediatrics, University of Rochester Medical Center, Rochester, New York (United States); Lawrence, B. Paige [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York (United States); Williams, Jacqueline P. [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States); Finkelstein, Jacob N., E-mail: Jacob_Finkelstein@urmc.rochester.edu [Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York (United States); Department of Pediatrics, University of Rochester Medical Center, Rochester, New York (United States); Department of Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States)

2013-05-01

Purpose: To address whether irradiation-induced changes in the lung environment alter responses to a viral challenge delivered late after exposure but before the appearance of late lung radiation injury. Methods and Materials: C57BL/6J mice received either lung alone or combined lung and whole-body irradiation (0-15 Gy). At 10 weeks after irradiation, animals were infected with 120 HAU influenza virus strain A/HKx31. Innate and adaptive immune cell recruitment was determined using flow cytometry. Cytokine and chemokine production and protein leakage into the lung after infection were assessed. Results: Prior irradiation led to a dose-dependent failure to regain body weight after infection and exacerbated mortality, but it did not affect virus-specific immune responses or virus clearance. Surviving irradiated animals displayed a persistent increase in total protein in bronchoalveolar lavage fluid and edema. Conclusions: Lung irradiation increased susceptibility to death after infection with influenza virus and impaired the ability to complete recovery. This altered response does not seem to be due to a radiation effect on the immune response, but it may possibly be an effect on epithelial repair.

Simultaneous deletion of the 9GL and UK genes from the African swine fever virus Georgia 2007 isolate results in virus attenuation and may be a potential virus vaccine strain

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African Swine Fever Virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs that has significant economic consequences for the swine industry. The control of African Swine Fever (ASF) has been hampered by the unavailability of vaccines. Successful experi...

Comparative Efficacy of Feline Leukemia Virus (FeLV) Inactivated Whole-Virus Vaccine and Canarypox Virus-Vectored Vaccine during Virulent FeLV Challenge and Immunosuppression.

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Patel, M; Carritt, K; Lane, J; Jayappa, H; Stahl, M; Bourgeois, M

2015-07-01

Four vaccines for feline leukemia virus (FeLV) are available in the United States. This study's purpose was to compare the efficacy of Nobivac feline 2-FeLV (an inactivated, adjuvanted whole-virus vaccine) and PureVax recombinant FeLV (a live, canarypox virus-vectored vaccine) following FeLV challenge. Cats were vaccinated at 9 and 12 weeks with Nobivac feline 2-FeLV (group A, n = 11) or PureVax recombinant FeLV (group B, n = 10). Group C (n = 11) comprised unvaccinated controls. At 3 months postvaccination, cats were immunosuppressed and challenged with FeLV-A/61E. The outcomes measured were persistent antigenemia at 12 weeks postchallenge (PC) and proviral DNA and viral RNA at 3 to 9 weeks PC. Persistent antigenemia was observed in 0 of 11 cats in group A, 5 of 10 cats in group B, and 10 of 11 cats in group C. Group A was significantly protected compared to those in groups B (P 0.063). The preventable fraction was 100% for group A and 45% for group B. At 9 weeks PC, proviral DNA and viral RNA were detected 1 of 11 cats in group A, 6 of 10 cats in group B, and 9 of 11 cats in group C. Nucleic acid loads were significantly lower in group A than in group C (P feline 2-FeLV-vaccinated cats were fully protected against persistent antigenemia and had significantly smaller amounts of proviral DNA and plasma viral RNA loads than PureVax recombinant FeLV-vaccinated cats and unvaccinated controls. Copyright © 2015, Patel et al.

Immunopathology of highly virulent pathogens: insights from Ebola virus.

Science.gov (United States)

Zampieri, Carisa A; Sullivan, Nancy J; Nabel, Gary J

2007-11-01

Ebola virus is a highly virulent pathogen capable of inducing a frequently lethal hemorrhagic fever syndrome. Accumulating evidence indicates that the virus actively subverts both innate and adaptive immune responses and triggers harmful inflammatory responses as it inflicts direct tissue damage. The host immune system is ultimately overwhelmed by a combination of inflammatory factors and virus-induced cell damage, particularly in the liver and vasculature, often leading to death from septic shock. We summarize the mechanisms of immune dysregulation and virus-mediated cell damage in Ebola virus-infected patients. Future approaches to prevention and treatment of infection will be guided by answers to unresolved questions about interspecies transmission, molecular mechanisms of pathogenesis, and protective adaptive and innate immune responses to Ebola virus.

Two Genetically Similar H9N2 Influenza A Viruses Show Different Pathogenicity in Mice

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Qingtao Liu

2016-11-01

Full Text Available H9N2 Avian influenza virus has repeatedly infected humans and other mammals, which highlights the need to determine the pathogenicity and the corresponding mechanism of this virus for mammals. In this study, we found two H9N2 viruses with similar genetic background but with different pathogenicity in mice. The A/duck/Nanjing/06/2003 (NJ06 virus was highly pathogenic for mice, with a 50% mouse lethal dose of 102.83 50% egg infectious dose, whereas the A/duck/Nanjing/01/1999 (NJ01 virus was low pathogenic for mice, with a 50% mouse lethal dose of >106.81 50% egg infectious dose. Further studies showed that the NJ06 virus grew faster and reached significantly higher titers than NJ01 in vivo and in vitro. Moreover, the NJ06 virus induced more severe lung lesions, and higher levels of inflammatory cellular infiltration and cytokine response in lungs than NJ01 did. However, only twelve different amino acid residues (HA-K157E, NA-A9T, NA-R435K, PB2-T149P, PB2-K627E, PB1-R187K, PA-L548M, PA-M550L, NP-G127E, NP-P277H, NP-D340N, NS1-D171N were found between the two viruses, and all these residues except for NA-R435K were located in the known functional regions involved in interaction of viral proteins or between the virus and host factors. Summary, our results suggest that multiple amino acid differences may be responsible for the higher pathogenicity of the NJ06 virus for mice, resulting in lethal infection, enhanced viral replication, severe lung lesions, and excessive inflammatory cellular infiltration and cytokine response in lungs. These observations will be helpful for better understanding the pathogenic potential and the corresponding molecular basis of H9N2 viruses that might pose threats to human health in the future.

Influenza type A virus: an outstandingly protean pathogen and a potent modular weapon.

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Shoham, Dany

2013-05-01

A remarkable debate recently arose on a global scale, about bioethics, biohazard, bioweaponry and bioterrorism issues related to scientific research concerning the induced transition of the highly lethal H5N1 avian flu virus from a non-pandemic to a tentatively pandemic strain, which might fall into malevolent hands. Appreciable ecogenetic complexity marks the main attributes of influenza type A viruses, namely infectivity, virulence, antigenicity, transmissibility, host range, endemicity, and epidemicity. They all shape, conjunctively, the outstanding protean nature of this pathogen, hence the modularity of the latter as a potent weapon. The present analysis inquires into those attributes, so as to profile and gauge threat, usability, impact and coping, particularly that the dimension of genetic engineering of this virus largely amplifies its potential. Within that context, various human interventions and misuses, including human experimental infections, undesirable vaccinations, as well as unauthorized and unskillful operations, led to bad corollaries and are also discussed in the present study. Altogether, a variety of interrelated properties underlying the complicatedness of and menaces posed by influenza A virus as a grave medical challenge, a dually explorable pathogen, and a modular biological warfare agent, are thereby illuminated, alongside with their scientific, strategic and practical implications.

Foot-and-mouth disease virus 5'-terminal S fragment is required for replication and modulation of the innate immune response in host cells.

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Kloc, Anna; Diaz-San Segundo, Fayna; Schafer, Elizabeth A; Rai, Devendra K; Kenney, Mary; de Los Santos, Teresa; Rieder, Elizabeth

2017-12-01

The S fragment of the FMDV 5' UTR is predicted to fold into a long stem-loop structure and it has been implicated in virus-host protein interactions. In this study, we report the minimal S fragment sequence required for virus viability and show a direct correlation between the extent of the S fragment deletion mutations and attenuated phenotypes. Furthermore, we provide novel insight into the role of the S fragment in modulating the host innate immune response. Importantly, in an FMDV mouse model system, all animals survive the inoculation with the live A 24 FMDV-S 4 mutant, containing a 164 nucleotide deletion in the upper S fragment loop, at a dose 1000 higher than the one causing lethality by parental A 24 FMDV, indicating that the A 24 FMDV-S 4 virus is highly attenuated in vivo. Additionally, mice exposed to high doses of live A 24 FMDV-S 4 virus are fully protected when challenged with parental A 24 FMDV virus. Published by Elsevier Inc.

Immunogenicity of NYVAC Prime-Protein Boost Human Immunodeficiency Virus Type 1 Envelope Vaccination and Simian-Human Immunodeficiency Virus Challenge of Nonhuman Primates.

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Saunders, Kevin O; Santra, Sampa; Parks, Robert; Yates, Nicole L; Sutherland, Laura L; Scearce, Richard M; Balachandran, Harikrishnan; Bradley, Todd; Goodman, Derrick; Eaton, Amanda; Stanfield-Oakley, Sherry A; Tartaglia, James; Phogat, Sanjay; Pantaleo, Giuseppe; Esteban, Mariano; Gomez, Carmen E; Perdiguero, Beatriz; Jacobs, Bertram; Kibler, Karen; Korber, Bette; Montefiori, David C; Ferrari, Guido; Vandergrift, Nathan; Liao, Hua-Xin; Tomaras, Georgia D; Haynes, Barton F

2018-04-15

A preventive human immunodeficiency virus type 1 (HIV-1) vaccine is an essential part of the strategy to eradicate AIDS. A critical question is whether antibodies that do not neutralize primary isolate (tier 2) HIV-1 strains can protect from infection. In this study, we investigated the ability of an attenuated poxvirus vector (NYVAC) prime-envelope gp120 boost to elicit potentially protective antibody responses in a rhesus macaque model of mucosal simian-human immunodeficiency virus (SHIV) infection. NYVAC vector delivery of a group M consensus envelope, trivalent mosaic envelopes, or a natural clade B isolate B.1059 envelope elicited antibodies that mediated neutralization of tier 1 viruses, cellular cytotoxicity, and phagocytosis. None of the macaques made neutralizing antibodies against the tier 2 SHIV SF162P3 used for mucosal challenge. Significant protection from infection was not observed for the three groups of vaccinated macaques compared to unvaccinated macaques, although binding antibody to HIV-1 Env correlated with decreased viremia after challenge. Thus, NYVAC Env prime-gp120 boost vaccination elicited polyfunctional, nonneutralizing antibody responses with minimal protective activity against tier 2 SHIV mucosal challenge. IMPORTANCE The antibody responses that confer protection against HIV-1 infection remain unknown. Polyfunctional antibody responses correlated with time to infection in previous macaque studies. Determining the ability of vaccines to induce these types of responses is critical for understanding how to improve upon the one efficacious human HIV-1 vaccine trial completed thus far. We characterized the antibody responses induced by a NYVAC-protein vaccine and determined the protective capacity of polyfunctional antibody responses in an R5, tier 2 mucosal SHIV infection model. Copyright © 2018 American Society for Microbiology.

Novel rabies virus-neutralizing epitope recognized by human monoclonal antibody: Fine mapping and escape mutant analysis

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Marissen, W.E.; Kramer, R.A.; Rice, A.; Weldon, W.C.; Niezgoda, M.; Faber, M.; Slootstra, J.W.; Meloen, R.H.; Clijsters-van der Horst, M.; Visser, T.J.; Jongeneelen, M.; Thijsse, S.; Throsby, M.; Kruif, de J.; Rupprecht, C.E.; Dietzschold, B.; Goudsmit, J.; Bakker, A.B.H.

2005-01-01

Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We

Novel rabies virus-neutralizing epitope recognized by human monoclonal antibody: fine mapping and escape mutant analysis

NARCIS (Netherlands)

Marissen, Wilfred E.; Kramer, R. Arjen; Rice, Amy; Weldon, William C.; Niezgoda, Michael; Faber, Milosz; Slootstra, Jerry W.; Meloen, Rob H.; Clijsters-van der Horst, Marieke; Visser, Therese J.; Jongeneelen, Mandy; Thijsse, Sandra; Throsby, Mark; de Kruif, John; Rupprecht, Charles E.; Dietzschold, Bernhard; Goudsmit, Jaap; Bakker, Alexander B. H.

2005-01-01

Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We

Addressing the Challenges of Hepatitis C Virus Resistance and Treatment Failure

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Che C. Colpitts

2016-08-01

Full Text Available Chronic hepatitis C is a major cause of chronic liver disease, including liver cirrhosis and hepatocellular carcinoma. The development of direct-acting antivirals (DAAs revolutionized hepatitis C virus (HCV treatment by offering genuine prospects for the first comprehensive cure of a chronic viral infection in humans. While antiviral resistance is a significant limitation for interferon-based therapies, resistance and treatment failure still appear to be present in a small fraction of patients even in state-of-the-art DAA combination therapies. Therefore, treatment failure and resistance still remain a clinical challenge for the management of patients not responding to DAAs. In this special issue of Viruses on HCV drug resistance, mechanisms of antiviral resistance for different classes of antiviral drugs are described. Furthermore, the detection and monitoring of resistance in clinical practice, the clinical impact of resistance in different patient groups and strategies to prevent and address resistance and treatment failure using complementary antiviral strategies are reviewed.

Addressing the Challenges of Hepatitis C Virus Resistance and Treatment Failure.

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Colpitts, Che C; Baumert, Thomas F

2016-08-16

Chronic hepatitis C is a major cause of chronic liver disease, including liver cirrhosis and hepatocellular carcinoma. The development of direct-acting antivirals (DAAs) revolutionized hepatitis C virus (HCV) treatment by offering genuine prospects for the first comprehensive cure of a chronic viral infection in humans. While antiviral resistance is a significant limitation for interferon-based therapies, resistance and treatment failure still appear to be present in a small fraction of patients even in state-of-the-art DAA combination therapies. Therefore, treatment failure and resistance still remain a clinical challenge for the management of patients not responding to DAAs. In this special issue of Viruses on HCV drug resistance, mechanisms of antiviral resistance for different classes of antiviral drugs are described. Furthermore, the detection and monitoring of resistance in clinical practice, the clinical impact of resistance in different patient groups and strategies to prevent and address resistance and treatment failure using complementary antiviral strategies are reviewed.

Induction of influenza-specific mucosal immunity by an attenuated recombinant Sendai virus.

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Thuc-vy L Le

2011-04-01

Full Text Available Many pathogens initiate infection at the mucosal surfaces; therefore, induction of mucosal immune responses is a first level of defense against infection and is the most powerful means of protection. Although intramuscular injection is widely used for vaccination and is effective at inducing circulating antibodies, it is less effective at inducing mucosal antibodies.Here we report a novel recombinant, attenuated Sendai virus vector (GP42-H1 in which the hemagglutinin (HA gene of influenza A virus was introduced into the Sendai virus genome as an additional gene. Infection of CV-1 cells by GP42-H1 resulted in cell surface expression of the HA protein. Intranasal immunization of mice with 1,000 plaque forming units (pfu of GP42-H1 induced HA-specific IgG and IgA antibodies in the blood, bronchoalveolar lavage fluid, fecal pellet extracts and saliva. The HA-specific antibody titer induced by GP42-H1 closely resembles the titer induced by sublethal infection by live influenza virus; however, in contrast to infection by influenza virus, immunization with GP42-H1 did not result in disease symptoms or the loss of body weight. In mice that were immunized with GP42-H1 and then challenged with 5LD(50 (1250 pfu of influenza virus, no significant weight loss was observed and other visual signs of morbidity were not detected.These results demonstrate that the GP42-H1 Sendai virus recombinant is able to confer full protection from lethal infection by influenza virus, supporting the conclusion that it is a safe and effective mucosal vaccine vector.

Preventative Vaccines for Zika Virus Outbreak: Preliminary Evaluation.

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Kim, Eun; Erdos, Geza; Huang, Shaohua; Kenniston, Thomas; Falo, Louis D; Gambotto, Andrea

2016-11-01

Since it emerged in Brazil in May 2015, the mosquito-borne Zika virus (ZIKV) has raised global concern due to its association with a significant rise in the number of infants born with microcephaly and neurological disorders such as Guillain-Barré syndrome. We developed prototype subunit and adenoviral-based Zika vaccines encoding the extracellular portion of the ZIKV envelope gene (E) fused to the T4 fibritin foldon trimerization domain (Efl). The subunit vaccine was delivered intradermally through carboxymethyl cellulose microneedle array (MNA). The immunogenicity of these two vaccines, named Ad5.ZIKV-Efl and ZIKV-rEfl, was tested in C57BL/6 mice. Prime/boost immunization regimen was associated with induction of a ZIKV-specific antibody response, which provided neutralizing immunity. Moreover, protection was evaluated in seven-day-old pups after virulent ZIKV intraperitoneal challenge. Pups born to mice immunized with Ad5.ZIKV-Efl were all protected against lethal challenge infection without weight loss or neurological signs, while pups born to dams immunized with MNA-ZIKV-rEfl were partially protected (50%). No protection was seen in pups born to phosphate buffered saline-immunized mice. This study illustrates the preliminary efficacy of the E ZIKV antigen vaccination in controlling ZIKV infectivity, providing a promising candidate vaccine and antigen format for the prevention of Zika virus disease. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

DNA immunization with a herpes simplex virus 2 bacterial artificial chromosome

International Nuclear Information System (INIS)

Meseda, Clement A.; Schmeisser, Falko; Pedersen, Robin; Woerner, Amy; Weir, Jerry P.

2004-01-01

Construction of a herpes simplex virus 2 (HSV-2) bacterial artificial chromosome (BAC) is described. BAC vector sequences were inserted into the thymidine kinase gene of HSV-2 by homologous recombination. DNA from cells infected with the resulting recombinant virus was transformed into E. coli, and colonies containing the HSV-2 BAC (HSV2-BAC) were isolated and analyzed for the expected genotype. HSV2-BAC DNA was infectious when transfected back into mammalian cells and the resulting virus was thymidine kinase negative. When used to immunize mice, the HSV2-BAC DNA elicited a strong HSV-2 specific antibody response that was equal to or greater than live virus immunization. Further, HSV2-BAC immunization was protective when animals were challenged with a lethal dose of virus. The utility of the HSV2-BAC for construction of recombinant virus genomes was demonstrated by elimination of the HSV-2 glycoprotein D (gD) gene. A recombinant HSV-2 BAC with the gD gene deleted was isolated and shown to be incapable of producing infectious virus following transfection unless an HSV gD gene was expressed in a complementing cell line. Immunization of mice with the HSV2 gD-BAC also elicited an HSV-2 specific antibody response and was protective. The results demonstrate the feasibility of DNA immunization with HSV-2 bacterial artificial chromosomes for replicating and nonreplicating candidate HSV-2 vaccines, as well as the utility of BAC technology for construction and maintenance of novel HSV-2 vaccines. The results further suggest that such technology will be a powerful tool for dissecting the immune response to HSV-2

CRISPR-Cas9, a tool to efficiently increase the development of recombinant African swine fever viruses

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African swine fever is a contagious and often lethal disease for domestic pigs with a significant economic impact on the swine industry. The etiological agent, African swine fever virus (ASFV), is a highly structurally complex double stranded DNA virus. No effective vaccines or antiviral treatment ...

A replicating cytomegalovirus-based vaccine encoding a single Ebola virus nucleoprotein CTL epitope confers protection against Ebola virus.

Directory of Open Access Journals (Sweden)

Yoshimi Tsuda

2011-08-01

Full Text Available Human outbreaks of Ebola virus (EBOV are a serious human health concern in Central Africa. Great apes (gorillas/chimpanzees are an important source of EBOV transmission to humans due to increased hunting of wildlife including the 'bush-meat' trade. Cytomegalovirus (CMV is an highly immunogenic virus that has shown recent utility as a vaccine platform. CMV-based vaccines also have the unique potential to re-infect and disseminate through target populations regardless of prior CMV immunity, which may be ideal for achieving high vaccine coverage in inaccessible populations such as great apes.We hypothesize that a vaccine strategy using CMV-based vectors expressing EBOV antigens may be ideally suited for use in inaccessible wildlife populations. To establish a 'proof-of-concept' for CMV-based vaccines against EBOV, we constructed a mouse CMV (MCMV vector expressing a CD8+ T cell epitope from the nucleoprotein (NP of Zaire ebolavirus (ZEBOV (MCMV/ZEBOV-NP(CTL. MCMV/ZEBOV-NP(CTL induced high levels of long-lasting (>8 months CD8+ T cells against ZEBOV NP in mice. Importantly, all vaccinated animals were protected against lethal ZEBOV challenge. Low levels of anti-ZEBOV antibodies were only sporadically detected in vaccinated animals prior to ZEBOV challenge suggesting a role, at least in part, for T cells in protection.This study demonstrates the ability of a CMV-based vaccine approach to protect against an highly virulent human pathogen, and supports the potential for 'disseminating' CMV-based EBOV vaccines to prevent EBOV transmission in wildlife populations.

CNS activity of Pokeweed Anti-viral Protein (PAP in mice infected with Lymphocytic Choriomeningitis Virus (LCMV

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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.

Vaccination-challenge studies with a Port Chalmers/73 (H3N2)-based swine influenza virus vaccine: Reflections on vaccine strain updates and on the vaccine potency test.

Science.gov (United States)

De Vleeschauwer, Annebel; Qiu, Yu; Van Reeth, Kristien

2015-05-11

The human A/Port Chalmers/1/73 (H3N2) influenza virus strain, the supposed ancestor of European H3N2 swine influenza viruses (SIVs), was used in most commercial SIV vaccines in Europe until recently. If manufacturers want to update vaccine strains, they have to perform laborious intratracheal (IT) challenge experiments and demonstrate reduced virus titres in the lungs of vaccinated pigs. We aimed to examine (a) the ability of a Port Chalmers/73-based commercial vaccine to induce cross-protection against a contemporary European H3N2 SIV and serologic cross-reaction against H3N2 SIVs from Europe and North America and (b) the validity of intranasal (IN) challenge and virus titrations of nasal swabs as alternatives for IT challenge and titrations of lung tissue in vaccine potency tests. Pigs were vaccinated with Suvaxyn Flu(®) and challenged by the IT or IN route with sw/Gent/172/08. Post-vaccination sera were examined in haemagglutination-inhibition assays against vaccine and challenge strains and additional H3N2 SIVs from Europe and North America, including an H3N2 variant virus. Tissues of the respiratory tract and nasal swabs were collected 3 days post challenge (DPCh) and from 0-7 DPCh, respectively, and examined by virus titration. Two vaccinations consistently induced cross-reactive antibodies against European H3N2 SIVs from 1998-2012, but minimal or undetectable antibody titres against North American viruses. Challenge virus titres in the lungs, trachea and nasal mucosa of the vaccinated pigs were significantly reduced after both IT and IN challenge. Yet the reduction of virus titres and nasal shedding was greater after IT challenge. The Port Chalmers/73-based vaccine still offered protection against a European H3N2 SIV isolated 35 years later and with only 86.9% amino acid homology in its HA1, but it is unlikely to protect against H3N2 SIVs that are endemic in North America. We use our data to reflect on vaccine strain updates and on the vaccine potency test

Characterization of leptospiral proteins that afford partial protection in hamsters against lethal challenge with Leptospira interrogans.

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Atzingen, Marina V; Gonçales, Amane P; de Morais, Zenaide M; Araújo, Eduardo R; De Brito, Thales; Vasconcellos, Silvio A; Nascimento, Ana L T O

2010-09-01

Leptospirosis is a worldwide zoonosis caused by pathogenic Leptospira. The whole-genome sequence of Leptospira interrogans serovar Copenhageni together with bioinformatic tools allow us to search for novel antigen candidates suitable for improved vaccines against leptospirosis. This study focused on three genes encoding conserved hypothetical proteins predicted to be exported to the outer membrane. The genes were amplified by PCR from six predominant pathogenic serovars in Brazil. The genes were cloned and expressed in Escherichia coli strain BL21-SI using the expression vector pDEST17. The recombinant proteins tagged with N-terminal 6xHis were purified by metal-charged chromatography. The proteins were recognized by antibodies present in sera from hamsters that were experimentally infected. Immunization of hamsters followed by challenge with a lethal dose of a virulent strain of Leptospira showed that the recombinant protein rLIC12730 afforded statistically significant protection to animals (44 %), followed by rLIC10494 (40 %) and rLIC12922 (30 %). Immunization with these proteins produced an increase in antibody titres during subsequent boosters, suggesting the involvement of a T-helper 2 response. Although more studies are needed, these data suggest that rLIC12730 and rLIC10494 are promising candidates for a multivalent vaccine for the prevention of leptospirosis.

Avian influenza viruses that cause highly virulent infections in humans exhibit distinct replicative properties in contrast to human H1N1 viruses

Science.gov (United States)

Simon, Philippe F.; de La Vega, Marc-Antoine; Paradis, Éric; Mendoza, Emelissa; Coombs, Kevin M.; Kobasa, Darwyn; Beauchemin, Catherine A. A.

2016-04-01

Avian influenza viruses present an emerging epidemiological concern as some strains of H5N1 avian influenza can cause severe infections in humans with lethality rates of up to 60%. These have been in circulation since 1997 and recently a novel H7N9-subtyped virus has been causing epizootics in China with lethality rates around 20%. To better understand the replication kinetics of these viruses, we combined several extensive viral kinetics experiments with mathematical modelling of in vitro infections in human A549 cells. We extracted fundamental replication parameters revealing that, while both the H5N1 and H7N9 viruses replicate faster and to higher titers than two low-pathogenicity H1N1 strains, they accomplish this via different mechanisms. While the H7N9 virions exhibit a faster rate of infection, the H5N1 virions are produced at a higher rate. Of the two H1N1 strains studied, the 2009 pandemic H1N1 strain exhibits the longest eclipse phase, possibly indicative of a less effective neuraminidase activity, but causes infection more rapidly than the seasonal strain. This explains, in part, the pandemic strain’s generally slower growth kinetics and permissiveness to accept mutations causing neuraminidase inhibitor resistance without significant loss in fitness. Our results highlight differential growth properties of H1N1, H5N1 and H7N9 influenza viruses.

Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy.

Science.gov (United States)

Kandadi, Machender R; Yu, Xuejun; Frankel, Arthur E; Ren, Jun

2012-11-07

Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Wild type (WT) and cardiac-specific catalase overexpression mice were challenged with lethal toxin (2 μg/g, intraperotineally (i.p.)). Cardiomyocyte contractile and intracellular Ca(2+) properties were assessed 18 h later using an IonOptix edge-detection system. Proteasome function was assessed using chymotrypsin-like and caspase-like activities. GFP-LC3 puncta and Western blot analysis were used to evaluate autophagy and protein ubiquitination. Lethal toxin exposure suppressed cardiomyocyte contractile function (suppressed peak shortening, maximal velocity of shortening/re-lengthening, prolonged duration of shortening/re-lengthening, and impaired intracellular Ca(2+) handling), the effects of which were alleviated by catalase. In addition, lethal toxin triggered autophagy, mitochondrial and ubiquitin-proteasome defects, the effects of which were mitigated by catalase. Pretreatment of cardiomyocytes from catalase mice with the autophagy inducer rapamycin significantly attenuated or ablated catalase-offered protection against lethal toxin-induced cardiomyocyte dysfunction. On the other hand, the autophagy inhibitor 3-MA ablated or significantly attenuated lethal toxin-induced cardiomyocyte contractile anomalies. Our results suggest that catalase is protective against anthrax lethal toxin-induced cardiomyocyte contractile and intracellular Ca(2+) anomalies, possibly through regulation of autophagy and mitochondrial function.

E3L and F1L Gene Functions Modulate the Protective Capacity of Modified Vaccinia Virus Ankara Immunization in Murine Model of Human Smallpox

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Asisa Volz

2018-01-01

Full Text Available The highly attenuated Modified Vaccinia virus Ankara (MVA lacks most of the known vaccinia virus (VACV virulence and immune evasion genes. Today MVA can serve as a safety-tested next-generation smallpox vaccine. Yet, we still need to learn about regulatory gene functions preserved in the MVA genome, such as the apoptosis inhibitor genes F1L and E3L. Here, we tested MVA vaccine preparations on the basis of the deletion mutant viruses MVA-ΔF1L and MVA-ΔE3L for efficacy against ectromelia virus (ECTV challenge infections in mice. In non-permissive human tissue culture the MVA deletion mutant viruses produced reduced levels of the VACV envelope antigen B5. Upon mousepox challenge at three weeks after vaccination, MVA-ΔF1L and MVA-ΔE3L exhibited reduced protective capacity in comparison to wildtype MVA. Surprisingly, however, all vaccines proved equally protective against a lethal ECTV infection at two days after vaccination. Accordingly, the deletion mutant MVA vaccines induced high levels of virus-specific CD8+ T cells previously shown to be essential for rapidly protective MVA vaccination. These results suggest that inactivation of the anti-apoptotic genes F1L or E3L modulates the protective capacity of MVA vaccination most likely through the induction of distinct orthopoxvirus specific immunity in the absence of these viral regulatory proteins.

Recombinant rabies virus expressing dog GM-CSF is an efficacious oral rabies vaccine for dogs.

Science.gov (United States)

Zhou, Ming; Wang, Lei; Zhou, Songqin; Wang, Zhao; Ruan, Juncheng; Tang, Lijun; Jia, Ziming; Cui, Min; Zhao, Ling; Fu, Zhen F

2015-11-17

Developing efficacious oral rabies vaccines is an important step to increase immunization coverage for stray dogs, which are not accessible for parenteral vaccination. Our previous studies have demonstrated that recombinant rabies virus (RABV) expressing cytokines/chemokines induces robust protective immune responses after oral immunization in mice by recruiting and activating dendritic cells (DCs) and B cells. To develop an effective oral rabies vaccine for dogs, a recombinant attenuated RABV expressing dog GM-CSF, designated as LBNSE-dGM-CSF was constructed and used for oral vaccination in a dog model. Significantly more DCs or B cells were activated in the peripheral blood of dogs vaccinated orally with LBNSE-dGM-CSF than those vaccinated with the parent virus LBNSE, particularly at 3 days post immunization (dpi). As a result, significantly higher levels of virus neutralizing antibodies (VNAs) were detected in dogs immunized with LBNSE-dGM-CSF than with the parent virus. All the immunized dogs were protected against a lethal challenge with 4500 MICLD50 of wild-type RABV SXTYD01. LBNSE-dGM-CSF was found to replicate mainly in the tonsils after oral vaccination as detected by nested RT-PCR and immunohistochemistry. Taken together, our results indicate that LBNSE-dGM-CSF could be a promising oral rabies vaccine candidate for dogs.

Development of non-lethal methods for investigation of actinide uptake by wildlife

Energy Technology Data Exchange (ETDEWEB)

Johansen, M.; Child, D.; Davis, E.; Harrison, J.; Hotchkis, M.; Payne, T.; Thiruvoth, S. [Australian Nuclear Science and Technology Org. (Australia); Wood, M. [University of Salford (United Kingdom)

2014-07-01

There is growing interest in the use of non-lethal methods in radioecology and an International Union of Radioecology Task Group has been established to facilitate international cooperation in this field (http://iur-uir.org/en/task-groups/id-19-non-lethal-methods-in-radioecology). In this paper, we evaluate the use of lethally-, and non-lethally obtained samples (various body tissues, excreta and blood withdrawals as well as parasites and found bones) as indicators of contamination. Samples of mammals and reptiles were collected from the semi-arid former weapons test site at Maralinga, Australia and analysed for thorium, plutonium, and uranium isotopes by accelerator mass spectrometry and alpha-spectrometry. Most samples were of low mass and presented analytical challenges as a result. The plutonium concentrations in blood withdrawn from the marginal ear veins of Oryctolagus cuniculus (European rabbit) were successfully analysed using small samples (0.2 -7.9 ml, below the ∼10 ml threshold for safe extraction of blood from these rabbits). The results demonstrate that small-volume blood samples can serve as indicators of the presence of plutonium absorbed within other tissues (e.g., muscle, bone). However, the magnitude of the blood plutonium masses were poorly correlated with those in muscle and bone due to the presence of a small number of outliers (without the outliers, correlations improved to r = +0.66 and r = +0.51 for muscle and bone respectively). The activity concentrations in parasitic ticks were relatively high compared with those of their hosts Pseudomys hermannsburgensis (sandy inland mouse) and Ctenophorus cristatus (crested dragon lizard). Successful measurement of tick samples indicates a potential for use of parasites as general indicators of contamination within host organisms. The concentrations of actinides in found bones of Macropus rufus (red kangaroo) and O. cuniculus demonstrated potential for their use as indicators of the areal extent of

Morbillivirus Experimental Animal Models: Measles Virus Pathogenesis Insights from Canine Distemper Virus.

Science.gov (United States)

da Fontoura Budaszewski, Renata; von Messling, Veronika

2016-10-11

Morbilliviruses share considerable structural and functional similarities. Even though disease severity varies among the respective host species, the underlying pathogenesis and the clinical signs are comparable. Thus, insights gained with one morbillivirus often apply to the other members of the genus. Since the Canine distemper virus (CDV) causes severe and often lethal disease in dogs and ferrets, it is an attractive model to characterize morbillivirus pathogenesis mechanisms and to evaluate the efficacy of new prophylactic and therapeutic approaches. This review compares the cellular tropism, pathogenesis, mechanisms of persistence and immunosuppression of the Measles virus (MeV) and CDV. It then summarizes the contributions made by studies on the CDV in dogs and ferrets to our understanding of MeV pathogenesis and to vaccine and drugs development.

Inactivation of RNA viruses by gamma irradiation

International Nuclear Information System (INIS)

Nonomiya, Takashi; Morimoto, Akinori; Iwatsuki, Kazuo; Tsutsumi, Takamasa; Ito, Hitoshi; Yamashiro, Tomio; Ishigaki, Isao.

1992-01-01

Four kinds of RNA viruses, Bluetongue virus (BT), Bovine Virus Diarrhea-Mucosal Disease virus (BVD·MD), Bovine Respiratory Syncytial virus (RS), Vesicular Stmatitis virus (VS), were subjected to various doses of gamma irradiation to determine the lethal doses. The D 10 values, which are the dose necessary to decimally reduce infectivity, ranged from 1.5 to 3.4 kGy under frozen condition at dry-ice temperature, and they increased to 2.6 to 5.0 kGy under frozen condition at dry-ice temperature. Serum neutralzing antibody titer of Infectious Bovine Rhinotracheitis (IBR) was not adversely changed by the exposure to 36 kGy of gamma-rays under frozen condition. Analysis of electrophoresis patterns of the bovine serum also reveales that the serum proteins were not remarkably affected, even when exposed to 36 kGy of gamma radiation under frozen condition. The results suggested that gamma irradiation under frozen condition is an effective means for inactivating both DNA and RNA viruses without adversely affecting serum proteins and neutralizing antibody titer. (author)

Inactivation of RNA viruses by gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Nonomiya, Takashi; Morimoto, Akinori; Iwatsuki, Kazuo; Tsutsumi, Takamasa (Ministry of Agriculture, Forestry and fisheries, Yokohama, Kanagawa (Japan). Animal Quarantine Service); Ito, Hitoshi; Yamashiro, Tomio; Ishigaki, Isao

1992-09-01

Four kinds of RNA viruses, Bluetongue virus (BT), Bovine Virus Diarrhea-Mucosal Disease virus (BVD[center dot]MD), Bovine Respiratory Syncytial virus (RS), Vesicular Stmatitis virus (VS), were subjected to various doses of gamma irradiation to determine the lethal doses. The D[sub 10] values, which are the dose necessary to decimally reduce infectivity, ranged from 1.5 to 3.4 kGy under frozen condition at dry-ice temperature, and they increased to 2.6 to 5.0 kGy under frozen condition at dry-ice temperature. Serum neutralzing antibody titer of Infectious Bovine Rhinotracheitis (IBR) was not adversely changed by the exposure to 36 kGy of gamma-rays under frozen condition. Analysis of electrophoresis patterns of the bovine serum also reveales that the serum proteins were not remarkably affected, even when exposed to 36 kGy of gamma radiation under frozen condition. The results suggested that gamma irradiation under frozen condition is an effective means for inactivating both DNA and RNA viruses without adversely affecting serum proteins and neutralizing antibody titer. (author).

A molecular assembly system for presentation of antigens on the surface of HBc virus-like particles

International Nuclear Information System (INIS)

Blokhina, Elena A.; Kuprianov, Victor V.; Stepanova, Ludmila A.; Tsybalova, Ludmila M.; Kiselev, Oleg I.; Ravin, Nikolai V.; Skryabin, Konstantin G.

2013-01-01

Hepatitis B virus-like particles, icosahedral structures formed by multiple core protein dimers, are promising immune-enhancing vaccine carriers for foreign antigens. Insertions into the surface-exposed immunodominant loop are especially immunogenic. However, the need to conserve the particulate structure to ensure high immunogenicity imposes restraints on the nature of the heterologous sequence that can be inserted. We propose a new approach to constructing HBc particles linked to the target epitopes that relies on non-covalent interactions between the epitope and pre-assembled unmodified HBc particles. Interaction was enabled by fusion of the epitope to the GSLLGRMKGA peptide, binding to the spike tips. This peptide may be used as a “binding tag” allowing in vitro construction of HBc particles carrying the target peptide. Such virus-like particles carrying multiple copies of the extracellular domain of the M2 protein of different influenza strains appeared to be highly immunogenic and protected immunised mice against a lethal influenza challenge.

A molecular assembly system for presentation of antigens on the surface of HBc virus-like particles

Energy Technology Data Exchange (ETDEWEB)

Blokhina, Elena A.; Kuprianov, Victor V. [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); Stepanova, Ludmila A.; Tsybalova, Ludmila M. [Research Institute of Influenza, Russian Federation Ministry of Health and Social Development, St. Petersburg (Russian Federation); Kiselev, Oleg I. [Research Institute of Influenza, Russian Federation Ministry of Health and Social Development, St. Petersburg (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation); Ravin, Nikolai V., E-mail: nravin@biengi.ac.ru [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation); Skryabin, Konstantin G. [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation)

2013-01-20

Hepatitis B virus-like particles, icosahedral structures formed by multiple core protein dimers, are promising immune-enhancing vaccine carriers for foreign antigens. Insertions into the surface-exposed immunodominant loop are especially immunogenic. However, the need to conserve the particulate structure to ensure high immunogenicity imposes restraints on the nature of the heterologous sequence that can be inserted. We propose a new approach to constructing HBc particles linked to the target epitopes that relies on non-covalent interactions between the epitope and pre-assembled unmodified HBc particles. Interaction was enabled by fusion of the epitope to the GSLLGRMKGA peptide, binding to the spike tips. This peptide may be used as a 'binding tag' allowing in vitro construction of HBc particles carrying the target peptide. Such virus-like particles carrying multiple copies of the extracellular domain of the M2 protein of different influenza strains appeared to be highly immunogenic and protected immunised mice against a lethal influenza challenge.

Clonal analysis of T-cell responses to herpes simplex virus: isolation, characterization and antiviral properties of an antigen-specific helper T-cell clone.

Science.gov (United States)

Leung, K N; Nash, A A; Sia, D Y; Wildy, P

1984-12-01

A herpes simplex virus (HSV)-specific long-term T-cell clone has been established from the draining lymph node cells of BALB/c mice; the cells required repeated in vitro restimulation with UV-irradiated virus. The established T-cell clone expresses the Thy-1 and Lyt-1+2,3- surface antigens. For optimal proliferation of the cloned cells, both the presence of specific antigen and an exogenous source of T-cell growth factor are required. The proliferative response of the cloned T cells was found to be virus-specific but it did not distinguish between HSV-1 and HSV-2. Adoptive cell transfer of the cloned T cells helped primed B cells to produce anti-herpes antibodies: the response was antigen-specific and cell dose-dependent. The clone failed to produce a significant DTH reaction in vivo, but did produce high levels of macrophage-activating factor. Furthermore, the T-cell clone could protect from HSV infection, as measured by a reduction in local virus growth, and by enhanced survival following the challenge of mice with a lethal dose of virus. The mechanism(s) whereby this clone protects in vivo is discussed.

Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

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Kandadi Machender R

2012-11-01

Full Text Available Abstract Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT and cardiac-specific catalase overexpression mice were challenged with lethal toxin (2 μg/g, intraperotineally (i.p.. Cardiomyocyte contractile and intracellular Ca2+ properties were assessed 18 h later using an IonOptix edge-detection system. Proteasome function was assessed using chymotrypsin-like and caspase-like activities. GFP-LC3 puncta and Western blot analysis were used to evaluate autophagy and protein ubiquitination. Results Lethal toxin exposure suppressed cardiomyocyte contractile function (suppressed peak shortening, maximal velocity of shortening/re-lengthening, prolonged duration of shortening/re-lengthening, and impaired intracellular Ca2+ handling, the effects of which were alleviated by catalase. In addition, lethal toxin triggered autophagy, mitochondrial and ubiquitin-proteasome defects, the effects of which were mitigated by catalase. Pretreatment of cardiomyocytes from catalase mice with the autophagy inducer rapamycin significantly attenuated or ablated catalase-offered protection against lethal toxin-induced cardiomyocyte dysfunction. On the other hand, the autophagy inhibitor 3-MA ablated or significantly attenuated lethal toxin-induced cardiomyocyte contractile anomalies. Conclusions Our results suggest that catalase is protective against anthrax lethal toxin-induced cardiomyocyte contractile and intracellular Ca2+ anomalies, possibly through regulation of autophagy and mitochondrial function.

Experimental chronic Pseudomonas aeruginosa lung infection in rats. Non-specific stimulation with LPS reduces lethality as efficiently as specific immunization

DEFF Research Database (Denmark)

Lange, K H; Hougen, H P; Høiby, N

1995-01-01

In a rat model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis, we investigated the possibility of preventing chronic lung inflammation or decreasing the progression of the infection. We compared the lethality, pathology, bacterial clearance, and immunogenicity after...... with either E. coli LPS or P. aeruginosa sonicate. Four and two weeks prior to challenge other rats were vaccinated with either E. coli LPS or P. aeruginosa sonicate. Controls did not receive any stimulation or vaccination. The lethality after challenge was lower in rats stimulated with E. coli LPS (p = 0...... but not to prevent the chronic P. aeruginosa lung infection and inflammation caused by alginate-embedded bacteria....

Factors influencing circadian rhythms in acetaminophen lethality.

Science.gov (United States)

Schnell, R C; Bozigian, H P; Davies, M H; Merrick, B A; Park, K S; McMillan, D A

1984-01-01

Experiments were conducted to examine the effects of changes in lighting schedules and food consumption on circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice. Under a normal lighting schedule (light: 06.00-18.00 h), male mice exhibited a circadian rhythm in acetaminophen lethality (peak: 18.00 h; nadir: 06.00, 10.00 h) and an inverse rhythm in hepatic glutathione concentrations (peak: 06.00, 10.00 h; nadir: 18.00 h). Under a reversed lighting schedule (light: 18.00-06.00 h) the glutathione rhythm was reversed and the rhythm in acetaminophen lethality was altered showing greater sensitivity to the drug. Under continuous light, there was a shift in the acetaminophen lethality and the hepatic glutathione rhythms. Under continuous dark, both rhythms were abolished. Under a normal lighting regimen, hepatic glutathione levels were closely correlated with food consumption; i.e., both were increased during the dark phase and decreased during the light phase. Fasting the mice for 12 h abolished the rhythms in acetaminophen lethality and hepatic glutathione levels; moreover, the lethality was increased and the hepatic glutathione levels were decreased. These experiments show that both lighting schedules and feeding can alter the circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice.

Protective Effect of Phillyrin on Lethal LPS-Induced Neutrophil Inflammation in Zebrafish

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Liling Yang

2017-10-01

Full Text Available Background/Aims: Forsythia suspensa Vahl. (Oleaceae fruits are widely used in traditional Chinese medicine to treat pneumonia, typhoid, dysentery, ulcers and oedema. Antibacterial and anti-inflammatory activities have been reported for phillyrin (PHN, the main ingredient in Forsythia suspensa Vahl fruits, in vitro. However, the underlying mechanisms in vivo remain poorly defined. In this study, we discovered that PHN exerted potent anti-inflammatory effects in lethal LPS-induced neutrophil inflammation by suppressing the MyD88-dependent signalling pathway in zebrafish. Methods: LPS-yolk microinjection was used to induce a lethal LPS-infected zebrafish model. The effect of PHN on the survival of zebrafish challenged with lethal LPS was evaluated using survival analysis. The effect of PHN on neutrophil inflammation grading in vivo was assessed by tracking neutrophils with a transgenic line. The effects of PHN on neutrophil production and migration were analysed by SB+ cell counts during consecutive hours after modelling. Additionally, key cytokines and members of the MyD88 signalling pathway that are involved in inflammatory response were detected using quantitative RT-PCR. To assess gene expression changes during consecutive hours after modelling, the IL-1β, IL-6, TNF-α, MyD88, TRIF, ERK1/2, JNK, IκBa and NF-κB expression levels were measured. Results: PHN could protect zebrafish against a lethal LPS challenge in a dose-dependent manner, as indicated by decreased neutrophil infltration, reduced tissue necrosis and increased survival rates. Up-regulated IL-1β, IL-6 and TNF-α expression also showed the same tendencies of depression by PHN. Critically, PHN significantly inhibited the LPS-induced activation of MyD88, IκBa, and NF-κB but did not affect the expression of ERK1/2 MAPKs or JNK MAPKs in LPS-stimulated zebrafish. Additionally, PHN regulated the MyD88/IκBα/NF-κB signalling pathway by controlling IκBα, IL-1β, IL-6, and TNF

Bacterially produced recombinant influenza vaccines based on virus-like particles.

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Andrea Jegerlehner

Full Text Available Although current influenza vaccines are effective in general, there is an urgent need for the development of new technologies to improve vaccine production timelines, capacities and immunogenicity. Herein, we describe the development of an influenza vaccine technology which enables recombinant production of highly efficient influenza vaccines in bacterial expression systems. The globular head domain of influenza hemagglutinin, comprising most of the protein's neutralizing epitopes, was expressed in E. coli and covalently conjugated to bacteriophage-derived virus-like particles produced independently in E.coli. Conjugate influenza vaccines produced this way were used to immunize mice and found to elicit immune sera with high antibody titers specific for the native influenza hemagglutinin protein and high hemagglutination-inhibition titers. Moreover vaccination with these vaccines induced full protection against lethal challenges with homologous and highly drifted influenza strains.

Venezuelan Equine Encephalitis Replicon Particles Can Induce Rapid Protection against Foot-and-Mouth Disease Virus

Science.gov (United States)

Diaz-San Segundo, Fayna; Dias, Camila C. A.; Moraes, Mauro P.; Weiss, Marcelo; Perez-Martin, Eva; Owens, Gary; Custer, Max; Kamrud, Kurt; de los Santos, Teresa

2013-01-01

We have previously shown that delivery of the porcine type I interferon gene (poIFN-α/β) with a replication-defective human adenovirus vector (adenovirus 5 [Ad5]) can sterilely protect swine challenged with foot-and-mouth disease virus (FMDV) 1 day later. However, the need of relatively high doses of Ad5 limits the applicability of such a control strategy in the livestock industry. Venezuelan equine encephalitis virus (VEE) empty replicon particles (VRPs) can induce rapid protection of mice against either homologous or, in some cases, heterologous virus challenge. As an alternative approach to induce rapid protection against FMDV, we have examined the ability of VRPs containing either the gene for green fluorescent protein (VRP-GFP) or poIFN-α (VRP-poIFN-α) to block FMDV replication in vitro and in vivo. Pretreatment of swine or bovine cell lines with either VRP significantly inhibited subsequent infection with FMDV as early as 6 h after treatment and for at least 120 h posttreatment. Furthermore, mice pretreated with either 107 or 108 infectious units of VRP-GFP and challenged with a lethal dose of FMDV 24 h later were protected from death. Protection was induced as early as 6 h after treatment and lasted for at least 48 h and correlated with induction of an antiviral response and production of IFN-α. By 6 h after treatment several genes were upregulated, and the number of genes and the level of induction increased at 24 h. Finally, we demonstrated that the chemokine IP-10, which is induced by IFN-α and VRP-GFP, is directly involved in protection against FMDV. PMID:23468490

Modified vaccinia virus Ankara protects macaques against respiratory challenge with monkeypox virus.

NARCIS (Netherlands)

K.J. Stittelaar (Koert); G. van Amerongen (Geert); I. Kondova (Ivanela); R.F. van Lavieren (Rob); F.H. Pistoor (Frank); H.G.M. Niesters (Bert); G.J.J. van Doornum (Gerard); B.A.M. van der Zeijst (Ben); L. Mateo (Luis); P.J. Chaplin (Paul); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

2005-01-01

textabstractThe use of classical smallpox vaccines based on vaccinia virus (VV) is associated with severe complications in both naive and immune individuals. Modified vaccinia virus Ankara (MVA), a highly attenuated replication-deficient strain of VV, has been proven to be safe in humans and

5-Lipoxygenase Deficiency Reduces Acetaminophen-Induced Hepatotoxicity and Lethality

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Miriam S. N. Hohmann

2013-01-01

Full Text Available 5-Lipoxygenase (5-LO converts arachidonic acid into leukotrienes (LTs and is involved in inflammation. At present, the participation of 5-LO in acetaminophen (APAP-induced hepatotoxicity and liver damage has not been addressed. 5-LO deficient (5-LO-/- mice and background wild type mice were challenged with APAP (0.3–6 g/kg or saline. The lethality, liver damage, neutrophil and macrophage recruitment, LTB4, cytokine production, and oxidative stress were assessed. APAP induced a dose-dependent mortality, and the dose of 3 g/kg was selected for next experiments. APAP induced LTB4 production in the liver, the primary target organ in APAP toxicity. Histopathological analysis revealed that 5-LO-/- mice presented reduced APAP-induced liver necrosis and inflammation compared with WT mice. APAP-induced lethality, increase of plasma levels of aspartate aminotransferase and alanine aminotransferase, liver cytokine (IL-1β, TNF-α, IFN-γ, and IL-10, superoxide anion, and thiobarbituric acid reactive substances production, myeloperoxidase and N-acetyl-β-D-glucosaminidase activity, Nrf2 and gp91phox mRNA expression, and decrease of reduced glutathione and antioxidant capacity measured by 2,2′-azinobis(3-ethylbenzothiazoline 6-sulfonate assay were prevented in 5-LO-/- mice compared to WT mice. Therefore, 5-LO deficiency resulted in reduced mortality due to reduced liver inflammatory and oxidative damage, suggesting 5-LO is a promising target to reduce APAP-induced lethality and liver inflammatory/oxidative damage.

Vaccination with recombinant RNA replicon particles protects chickens from H5N1 highly pathogenic avian influenza virus.

Directory of Open Access Journals (Sweden)

Stefan J Halbherr

Full Text Available Highly pathogenic avian influenza viruses (HPAIV of subtype H5N1 not only cause a devastating disease in domestic chickens and turkeys but also pose a continuous threat to public health. In some countries, H5N1 viruses continue to circulate and evolve into new clades and subclades. The rapid evolution of these viruses represents a problem for virus diagnosis and control. In this work, recombinant vesicular stomatitis virus (VSV vectors expressing HA of subtype H5 were generated. To comply with biosafety issues the G gene was deleted from the VSV genome. The resulting vaccine vector VSV*ΔG(HA was propagated on helper cells providing the VSV G protein in trans. Vaccination of chickens with a single intramuscular dose of 2×10⁸ infectious replicon particles without adjuvant conferred complete protection from lethal H5N1 infection. Subsequent application of the same vaccine strongly boosted the humoral immune response and completely prevented shedding of challenge virus and transmission to sentinel birds. The vaccine allowed serological differentiation of infected from vaccinated animals (DIVA by employing a commercially available ELISA. Immunized chickens produced antibodies with neutralizing activity against multiple H5 viruses representing clades 1, 2.2, 2.5, and low-pathogenic avian influenza viruses (classical clade. Studies using chimeric H1/H5 hemagglutinins showed that the neutralizing activity was predominantly directed against the globular head domain. In summary, these results suggest that VSV replicon particles are safe and potent DIVA vaccines that may help to control avian influenza viruses in domestic poultry.

Derangement of cellular plasma membranes due to non-lethal radiation doses

International Nuclear Information System (INIS)

Koeteles, G.J.; Kubasova, T.; Somosy, Z.; Horvath, L.

1983-01-01

Earlier observations in the laboratory on fibroblasts and various blood cells of animal and human origins pointed to alteration of concanavalin A binding sites of plasma membranes as well as to concomitant morphological changes and scanning electron microscopic appearance of cell surfaces following sub-lethal doses of X-, fission neutron and beta irradiations. The effects appeared early and existed temporarily; their intensities and the restitution of membrane function depended on radiation doses, types and conditions of cells. In the present paper further aspects of structural and functional derangements of plasma membranes are introduced which were provoked by X- and tritium beta irradiation in the dose range up to 2.5 Gy and in the concentration range from 3.7 kBq/mL, respectively. The state of membrane structure was followed by bindings of various ligands of different receptor requirements, concanavalin A, cationized ferritin and polio virus. In the case of X-irradiation the binding conditions suggest the shift of overall negative surface charges to less negative ones. It was also found that radiation-induced phenomena appear on the cell surface unevenly. Long- and short-term treatments of cells with 3 H-thymidine and 3 H-water also perturb the plasma membrane; beta irradiation affects it directly. Membrane structure and function are suggested to offer good biological models to study correlation of energy deposition and biological effects, both restricted to domains of nanometre range. The data give evidence for radiation-induced membrane alterations in the sub-lethal or non-lethal ranges which might have consequences in the development of stochastic and non-stochastic effects. (author)

Challenge Pools of Hepatitis C Virus Genotypes 1–6 Prototype Strains: Replication Fitness and Pathogenicity in Chimpanzees and Human Liver–Chimeric Mouse Models

Science.gov (United States)

Bukh, Jens; Meuleman, Philip; Tellier, Raymond; Engle, Ronald E.; Feinstone, Stephen M.; Eder, Gerald; Satterfield, William C.; Govindarajan, Sugantha; Krawczynski, Krzysztof; Miller, Roger H.; Leroux-Roels, Geert; Purcell, Robert H.

2010-01-01

Chimpanzees represent the only animal model for studies of the natural history of hepatitis C virus (HCV). To generate virus stocks of important HCV variants, we infected chimpanzees with HCV strains of genotypes 1–6 and determined the infectivity titer of acute-phase plasma pools in additional animals. The courses of first- and second-passage infections were similar, with early appearance of viremia, HCV RNA titers of >104.7 IU/mL, and development of acute hepatitis; the chronicity rate was 56%. The challenge pools had titers of 103–105 chimpanzee infectious doses/mL. Human liver–chimeric mice developed high-titer infections after inoculation with the challenge viruses of genotypes 1–6. Inoculation studies with different doses of the genotype 1b pool suggested that a relatively high virus dose is required to consistently infect chimeric mice. The challenge pools represent a unique resource for studies of HCV molecular virology and for studies of pathogenesis, protective immunity, and vaccine efficacy in vivo. PMID:20353362

Divergent H7 immunogens offer protection from H7N9 virus challenge.

Science.gov (United States)

Krammer, Florian; Albrecht, Randy A; Tan, Gene S; Margine, Irina; Hai, Rong; Schmolke, Mirco; Runstadler, Jonathan; Andrews, Sarah F; Wilson, Patrick C; Cox, Rebecca J; Treanor, John J; García-Sastre, Adolfo; Palese, Peter

2014-04-01

The emergence of avian H7N9 viruses in humans in China has renewed concerns about influenza pandemics emerging from Asia. Vaccines are still the best countermeasure against emerging influenza virus infections, but the process from the identification of vaccine seed strains to the distribution of the final product can take several months. In the case of the 2009 H1N1 pandemic, a vaccine was not available before the first pandemic wave hit and therefore came too late to reduce influenza morbidity. H7 vaccines based on divergent isolates of the Eurasian and North American lineages have been tested in clinical trials, and seed strains and reagents are already available and can potentially be used initially to curtail influenza-induced disease until a more appropriately matched H7N9 vaccine is ready. In a challenge experiment in the mouse model, we assessed the efficacy of both inactivated virus and recombinant hemagglutinin vaccines made from seed strains that are divergent from H7N9 from each of the two major H7 lineages. Furthermore, we analyzed the cross-reactive responses of sera from human subjects vaccinated with heterologous North American and Eurasian lineage H7 vaccines to H7N9. Vaccinations with inactivated virus and recombinant hemagglutinin protein preparations from both lineages raised hemagglutination-inhibiting antibodies against H7N9 viruses and protected mice from stringent viral challenges. Similar cross-reactivity was observed in sera of human subjects from a clinical trial with a divergent H7 vaccine. Existing H7 vaccine candidates based on divergent strains could be used as a first line of defense against an H7N9 pandemic. In addition, this also suggests that H7N9 vaccines that are currently under development might be stockpiled and used for divergent avian H7 strains that emerge in the future. Sporadic human infections with H7N9 viruses started being reported in China in the early spring of 2013. Despite a significant drop in the number of

Swine interferon-induced transmembrane protein, sIFITM3, inhibits foot-and-mouth disease virus infection in vitro and in vivo.

Science.gov (United States)

Xu, Jinfang; Qian, Ping; Wu, Qunfeng; Liu, Shasha; Fan, Wenchun; Zhang, Keshan; Wang, Rong; Zhang, Huawei; Chen, Huanchun; Li, Xiangmin

2014-09-01

The interferon-induced transmembrane protein 3 (IFITM3) is a widely expressed potent antiviral effector of the host innate immune system. It restricts a diverse group of pathogenic, enveloped viruses, by interfering with endosomal fusion. In this report, the swine IFITM3 (sIFITM3) gene was cloned. It shares the functionally conserved CD225 domain and multiple critical amino acid residues (Y19, F74, F77, R86 and Y98) with its human ortholog, which are essential for antiviral activity. Ectopic expression of sIFITM3 significantly inhibited non-enveloped foot-and-mouth disease virus (FMDV) infection in BHK-21 cells. Furthermore, sIFITM3 blocked FMDV infection at early steps in the virus life cycle by disrupting viral attachment to the host cell surface. Importantly, inoculation of 2-day-old suckling mice with a plasmid expressing sIFITM3 conferred protection against lethal challenge with FMDV. These results suggest that sIFITM3 is a promising antiviral agent and that can safeguard the host from infection with FMDV. Copyright © 2014 Elsevier B.V. All rights reserved.

Tolerization with BLP down-regulates HMGB1 a critical mediator of sepsis-related lethality.

LENUS (Irish Health Repository)

Coffey, J Calvin

2012-02-03

Tolerization with bacterial lipoprotein (BLP) affords a significant survival benefit in sepsis. Given that high mobility group box protein-1 (HMGB1) is a recognized mediator of sepsis-related lethality, we determined if tolerization with BLP leads to alterations in HMGB1. In vitro, BLP tolerization led to a reduction in HMGB1 gene transcription. This was mirrored at the protein level, as HMGB1 protein expression and release were reduced significantly in BLP-tolerized human THP-1 monocytic cells. BLP tolerance in vivo led to a highly significant, long-term survival benefit following challenge with lethal dose BLP in C57BL\\/6 mice. This was associated with an attenuation of HMGB1 release into the circulation, as evidenced by negligible serum HMGB1 levels in BLP-tolerized mice. Moreover, HMGB1 levels in peritoneal macrophages from BLP-tolerized mice were reduced significantly. Hence, tolerization with BLP leads to a down-regulation of HMGB1 protein synthesis and release. The improved survival associated with BLP tolerance could thus be explained by a reduction in HMGB1, were the latter associated with lethality in BLP-related sepsis. In testing this hypothesis, it was noted that neutralization of HMGB1, using anti-HMGB1 antibodies, abrogated BLP-associated lethality almost completely. To conclude, tolerization with BLP leads to a down-regulation of HMGB1, thus offering a novel means of targeting the latter. HMGB1 is also a mediator of lethality in BLP-related sepsis.

Generation and characterization of P gene-deficient rabies virus

International Nuclear Information System (INIS)

Shoji, Youko; Inoue, Satoshi; Nakamichi, Kazuo; Kurane, Ichiro; Sakai, Takeo; Morimoto, Kinjiro

2004-01-01

Rabies virus (RV) deficient in the P gene was generated by reverse genetics from cDNA of HEP-Flury strain lacking the entire P gene. The defective virus was propagated and amplified by rescue of virus, using a cell line that complemented the functions of the deficient gene. The P gene-deficient (def-P) virus replicated its genome and produced progeny viruses in the cell lines that constitutively expressed the P protein, although it grew at a slightly retarded rate compared to the parental strain. In contrast, no progeny virus was produced in the infected host when the def-P virus-infected cells that did not express the P protein. However, we found that the def-P virus had the ability to perform primary transcription (by the virion-associated polymerase) in the infected host without de novo P protein synthesis. The def-P virus was apathogenic in adult and suckling mice, even when inoculated intracranially. Inoculation of def-P virus in mice induced high levels of virus-neutralizing antibody (VNA) and conferred protective immunity against a lethal rabies infection. These results demonstrate the potential utility of gene-deficient virus as a novel live attenuated rabies vaccine

CNS recruitment of CD8+ T lymphocytes specific for a peripheral virus infection triggers neuropathogenesis during polymicrobial challenge.

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Christine M Matullo

2011-12-01

Full Text Available Although viruses have been implicated in central nervous system (CNS diseases of unknown etiology, including multiple sclerosis and amyotrophic lateral sclerosis, the reproducible identification of viral triggers in such diseases has been largely unsuccessful. Here, we explore the hypothesis that viruses need not replicate in the tissue in which they cause disease; specifically, that a peripheral infection might trigger CNS pathology. To test this idea, we utilized a transgenic mouse model in which we found that immune cells responding to a peripheral infection are recruited to the CNS, where they trigger neurological damage. In this model, mice are infected with both CNS-restricted measles virus (MV and peripherally restricted lymphocytic choriomeningitis virus (LCMV. While infection with either virus alone resulted in no illness, infection with both viruses caused disease in all mice, with ∼50% dying following seizures. Co-infection resulted in a 12-fold increase in the number of CD8+ T cells in the brain as compared to MV infection alone. Tetramer analysis revealed that a substantial proportion (>35% of these infiltrating CD8+ lymphocytes were LCMV-specific, despite no detectable LCMV in CNS tissues. Mechanistically, CNS disease was due to edema, induced in a CD8-dependent but perforin-independent manner, and brain herniation, similar to that observed in mice challenged intracerebrally with LCMV. These results indicate that T cell trafficking can be influenced by other ongoing immune challenges, and that CD8+ T cell recruitment to the brain can trigger CNS disease in the apparent absence of cognate antigen. By extrapolation, human CNS diseases of unknown etiology need not be associated with infection with any particular agent; rather, a condition that compromises and activates the blood-brain barrier and adjacent brain parenchyma can render the CNS susceptible to pathogen-independent immune attack.

Equine H7N7 influenza A viruses are highly pathogenic in mice without adaptation: potential use as an animal model.

OpenAIRE

Kawaoka, Y

1991-01-01

Equine H7N7 influenza A viruses, representing a broad range of isolates, were lethal in mice without adaptation. After repeated passages, A/Equine/London/1416/73 acquired neurotropism upon intranasal infection. Thus, mice infected with equine influenza A viruses provide a model system for the study of highly virulent mammalian influenza viruses.

Viruses and human cancers: challenges for preventive strategies.

Science.gov (United States)

de The, G

1995-01-01

Virus-associated human cancers provide unique opportunities for preventive strategies. The role of human papilloma viruses (HPV 16 and 18), hepatitis B virus (HBV), Epstein-Barr herpes virus (EBV), and retroviruses (human immunodeficiency virus [HIV] and human T-cell leukemia/lymphoma virus [HTLV]) in the development of common carcinomas and lymphomas represents a major cancer threat, particularly among individuals residing in developing countries, which account for 80% of the world's population. Even though these viruses are not the sole etiological agents of these cancers (as would be the case for infectious diseases), different approaches can be implemented to significantly decrease the incidence of virus-associated malignancies. The first approach is vaccination, which is available for HBV and possibly soon for EBV. The long delay between primary viral infection and development of associated tumors as well as the cost involved with administering vaccinations detracts from the feasibility of such an approach within developing countries. The second approach is to increase efforts to detect pre-cancerous lesions or early tumors using immunovirological means. This would allow early diagnosis and better treatment. The third strategy is linked to the existence of disease susceptibility genes, and suggests that counseling be provided for individuals carrying these genes to encourage them to modify their lifestyles and other conditions associated with increased cancer risks (predictive oncology). Specific recommendations include: a) increase international studies that explore the causes of the large variations in prevalence of common cancers throughout the world; b) conduct interdisciplinary studies involving laboratory investigation and social sciences, which may suggest hypotheses that may then be tested experimentally; and c) promote more preventive and health enhancement strategies in addition to curative and replacement therapies. PMID:8741797

Development of a challenge-protective vaccine concept by modification of the viral RNA-dependent RNA polymerase of canine distemper virus.

Science.gov (United States)

Silin, D; Lyubomska, O; Ludlow, M; Duprex, W P; Rima, B K

2007-12-01

We demonstrate that insertion of the open reading frame of enhanced green fluorescent protein (EGFP) into the coding sequence for the second hinge region of the viral L (large) protein (RNA-dependent RNA polymerase) attenuates a wild-type canine distemper virus. Moreover, we show that single intranasal immunization with this recombinant virus provides significant protection against challenge with the virulent parental virus. Protection against wild-type challenge was gained either after recovery of cellular immunity postimmunization or after development of neutralizing antibodies. Insertion of EGFP seems to result in overattenuation of the virus, while our previous experiments demonstrated that the insertion of an epitope tag into a similar position did not affect L protein function. Thus, a desirable level of attenuation could be reached by manipulating the length of the insert (in the second hinge region of the L protein), providing additional tools for optimization of controlled attenuation. This strategy for controlled attenuation may be useful for a "quick response" in vaccine development against well-known and "new" viral infections and could be combined efficiently with other strategies of vaccine development and delivery systems.

Homologous and Heterologous Protection of Nonhuman Primates by Ebola and Sudan Virus-Like Particles

Science.gov (United States)

Warfield, Kelly L.; Dye, John M.; Wells, Jay B.; Unfer, Robert C.; Holtsberg, Frederick W.; Shulenin, Sergey; Vu, Hong; Swenson, Dana L.; Bavari, Sina; Aman, M. Javad

2015-01-01

Filoviruses cause hemorrhagic fever resulting in significant morbidity and mortality in humans. Several vaccine platforms that include multiple virus-vectored approaches and virus-like particles (VLPs) have shown efficacy in nonhuman primates. Previous studies have shown protection of cynomolgus macaques against homologous infection for Ebola virus (EBOV) and Marburg virus (MARV) following a three-dose vaccine regimen of EBOV or MARV VLPs, as well as heterologous protection against Ravn Virus (RAVV) following vaccination with MARV VLPs. The objectives of the current studies were to determine the minimum number of vaccine doses required for protection (using EBOV as the test system) and then demonstrate protection against Sudan virus (SUDV) and Taï Forest virus (TAFV). Using the EBOV nonhuman primate model, we show that one or two doses of VLP vaccine can confer protection from lethal infection. VLPs containing the SUDV glycoprotein, nucleoprotein and VP40 matrix protein provide complete protection against lethal SUDV infection in macaques. Finally, we demonstrate protective efficacy mediated by EBOV, but not SUDV, VLPs against TAFV; this is the first demonstration of complete cross-filovirus protection using a single component heterologous vaccine within the Ebolavirus genus. Along with our previous results, this observation provides strong evidence that it will be possible to develop and administer a broad-spectrum VLP-based vaccine that will protect against multiple filoviruses by combining only three EBOV, SUDV and MARV components. PMID:25793502

Homologous and heterologous protection of nonhuman primates by Ebola and Sudan virus-like particles.

Directory of Open Access Journals (Sweden)

Kelly L Warfield

Full Text Available Filoviruses cause hemorrhagic fever resulting in significant morbidity and mortality in humans. Several vaccine platforms that include multiple virus-vectored approaches and virus-like particles (VLPs have shown efficacy in nonhuman primates. Previous studies have shown protection of cynomolgus macaques against homologous infection for Ebola virus (EBOV and Marburg virus (MARV following a three-dose vaccine regimen of EBOV or MARV VLPs, as well as heterologous protection against Ravn Virus (RAVV following vaccination with MARV VLPs. The objectives of the current studies were to determine the minimum number of vaccine doses required for protection (using EBOV as the test system and then demonstrate protection against Sudan virus (SUDV and Taï Forest virus (TAFV. Using the EBOV nonhuman primate model, we show that one or two doses of VLP vaccine can confer protection from lethal infection. VLPs containing the SUDV glycoprotein, nucleoprotein and VP40 matrix protein provide complete protection against lethal SUDV infection in macaques. Finally, we demonstrate protective efficacy mediated by EBOV, but not SUDV, VLPs against TAFV; this is the first demonstration of complete cross-filovirus protection using a single component heterologous vaccine within the Ebolavirus genus. Along with our previous results, this observation provides strong evidence that it will be possible to develop and administer a broad-spectrum VLP-based vaccine that will protect against multiple filoviruses by combining only three EBOV, SUDV and MARV components.

Molecular characterization of African swine fever virus in apparently ...

African Journals Online (AJOL)

African swine fever (ASF) is a highly lethal and economically significant disease of domestic pigs in Uganda where outbreaks regularly occur. There is neither a vaccine nor treatment available for ASF control. Twenty two African swine fever virus (ASFV) genotypes (I - XXII) have been identified based on partial sequencing ...

In Vivo Efficacy of a Cocktail of Human Monoclonal Antibodies (CL184 Against Diverse North American Bat Rabies Virus Variants

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Richard Franka

2017-09-01

Full Text Available Following rabies virus (RABV exposure, a combination of thorough wound washing, multiple-dose vaccine administration and the local infiltration of rabies immune globulin (RIG are essential components of modern post-exposure prophylaxis (PEP. Although modern cell-culture-based rabies vaccines are increasingly used in many countries, RIG is much less available. The prohibitive cost of polyclonal serum RIG products has prompted a search for alternatives and design of anti-RABV monoclonal antibodies (MAbs that can be manufactured on a large scale with a consistent potency and lower production costs. Robust in vitro neutralization activity has been demonstrated for the CL184 MAb cocktail, a 1:1 protein mixture of two human anti-RABV MAbs (CR57/CR4098, against a large panel of RABV isolates. In this study, we used a hamster model to evaluate the efficacy of experimental PEP against a lethal challenge. Various doses of CL184 and commercial rabies vaccine were assessed for the ability to protect against lethal infection with representatives of four distinct bat RABV lineages of public health relevance: silver-haired bat (Ln RABV; western canyon bat (Ph RABV; big brown bat (Ef-w1 RABV and Mexican free-tailed bat RABV (Tb RABV. 42–100% of animals survived bat RABV infection when CL184 (in combination with the vaccine was administered. A dose-response relationship was observed with decreasing doses of CL184 resulting in increasing mortality. Importantly, CL184 was highly effective in neutralizing and clearing Ph RABV in vivo, even though CR4098 does not neutralize this virus in vitro. By comparison, 19–95% survivorship was observed if human RIG (20 IU/kg and vaccine were used following challenge with different bat viruses. Based on our results, CL184 represents an efficacious alternative for RIG. Both large-scale and lower cost production could ensure better availability and affordability of this critical life-saving biologic in rabies enzootic

Effect of cytokine-encoding plasmid delivery on immune response to Japanese encephalitis virus DNA vaccine in mice.

Science.gov (United States)

Bharati, Kaushik; Appaiahgari, Mohan Babu; Vrati, Sudhanshu

2005-01-01

We have previously shown that immunization of mice with plasmid pMEa synthesizing Japanese encephalitis virus (JEV) envelope protein induced anti-JEV humoral and cellular immune responses. We now show that intra-muscular co-administration of mice with pMEa and pGM-CSF, encoding murine granulocyte-macrophage colony-stimulating factor or pIL-2, encoding murine interleukin-2 given 4 days after pMEa, augmented anti-JEV antibody titers. This did not enhance the level of protection in immunized mice against JEV. However, intra-dermal co-administration of pMEa and pGM-CSF in mice using the gene gun, enhanced anti-JEV antibody titers resulting in an increased level of protection in mice against lethal JEV challenge.

A pandemic influenza H1N1 live vaccine based on modified vaccinia Ankara is highly immunogenic and protects mice in active and passive immunizations.

Directory of Open Access Journals (Sweden)

Annett Hessel

Full Text Available BACKGROUND: The development of novel influenza vaccines inducing a broad immune response is an important objective. The aim of this study was to evaluate live vaccines which induce both strong humoral and cell-mediated immune responses against the novel human pandemic H1N1 influenza virus, and to show protection in a lethal animal challenge model. METHODOLOGY/PRINCIPAL FINDINGS: For this purpose, the hemagglutinin (HA and neuraminidase (NA genes of the influenza A/California/07/2009 (H1N1 strain (CA/07 were inserted into the replication-deficient modified vaccinia Ankara (MVA virus--a safe poxviral live vector--resulting in MVA-H1-Ca and MVA-N1-Ca vectors. These live vaccines, together with an inactivated whole virus vaccine, were assessed in a lung infection model using immune competent Balb/c mice, and in a lethal challenge model using severe combined immunodeficient (SCID mice after passive serum transfer from immunized mice. Balb/c mice vaccinated with the MVA-H1-Ca virus or the inactivated vaccine were fully protected from lung infection after challenge with the influenza H1N1 wild-type strain, while the neuraminidase virus MVA-N1-Ca induced only partial protection. The live vaccines were already protective after a single dose and induced substantial amounts of neutralizing antibodies and of interferon-gamma-secreting (IFN-gamma CD4- and CD8 T-cells in lungs and spleens. In the lungs, a rapid increase of HA-specific CD4- and CD8 T cells was observed in vaccinated mice shortly after challenge with influenza swine flu virus, which probably contributes to the strong inhibition of pulmonary viral replication observed. In addition, passive transfer of antisera raised in MVA-H1-Ca vaccinated immune-competent mice protected SCID mice from lethal challenge with the CA/07 wild-type virus. CONCLUSIONS/SIGNIFICANCE: The non-replicating MVA-based H1N1 live vaccines induce a broad protective immune response and are promising vaccine candidates for

Bayesian inference of the number of factors in gene-expression analysis: application to human virus challenge studies

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Hero Alfred

2010-11-01

Full Text Available Abstract Background Nonparametric Bayesian techniques have been developed recently to extend the sophistication of factor models, allowing one to infer the number of appropriate factors from the observed data. We consider such techniques for sparse factor analysis, with application to gene-expression data from three virus challenge studies. Particular attention is placed on employing the Beta Process (BP, the Indian Buffet Process (IBP, and related sparseness-promoting techniques to infer a proper number of factors. The posterior density function on the model parameters is computed using Gibbs sampling and variational Bayesian (VB analysis. Results Time-evolving gene-expression data are considered for respiratory syncytial virus (RSV, Rhino virus, and influenza, using blood samples from healthy human subjects. These data were acquired in three challenge studies, each executed after receiving institutional review board (IRB approval from Duke University. Comparisons are made between several alternative means of per-forming nonparametric factor analysis on these data, with comparisons as well to sparse-PCA and Penalized Matrix Decomposition (PMD, closely related non-Bayesian approaches. Conclusions Applying the Beta Process to the factor scores, or to the singular values of a pseudo-SVD construction, the proposed algorithms infer the number of factors in gene-expression data. For real data the "true" number of factors is unknown; in our simulations we consider a range of noise variances, and the proposed Bayesian models inferred the number of factors accurately relative to other methods in the literature, such as sparse-PCA and PMD. We have also identified a "pan-viral" factor of importance for each of the three viruses considered in this study. We have identified a set of genes associated with this pan-viral factor, of interest for early detection of such viruses based upon the host response, as quantified via gene-expression data.

Bayesian inference of the number of factors in gene-expression analysis: application to human virus challenge studies.

Science.gov (United States)

Chen, Bo; Chen, Minhua; Paisley, John; Zaas, Aimee; Woods, Christopher; Ginsburg, Geoffrey S; Hero, Alfred; Lucas, Joseph; Dunson, David; Carin, Lawrence

2010-11-09

Nonparametric Bayesian techniques have been developed recently to extend the sophistication of factor models, allowing one to infer the number of appropriate factors from the observed data. We consider such techniques for sparse factor analysis, with application to gene-expression data from three virus challenge studies. Particular attention is placed on employing the Beta Process (BP), the Indian Buffet Process (IBP), and related sparseness-promoting techniques to infer a proper number of factors. The posterior density function on the model parameters is computed using Gibbs sampling and variational Bayesian (VB) analysis. Time-evolving gene-expression data are considered for respiratory syncytial virus (RSV), Rhino virus, and influenza, using blood samples from healthy human subjects. These data were acquired in three challenge studies, each executed after receiving institutional review board (IRB) approval from Duke University. Comparisons are made between several alternative means of per-forming nonparametric factor analysis on these data, with comparisons as well to sparse-PCA and Penalized Matrix Decomposition (PMD), closely related non-Bayesian approaches. Applying the Beta Process to the factor scores, or to the singular values of a pseudo-SVD construction, the proposed algorithms infer the number of factors in gene-expression data. For real data the "true" number of factors is unknown; in our simulations we consider a range of noise variances, and the proposed Bayesian models inferred the number of factors accurately relative to other methods in the literature, such as sparse-PCA and PMD. We have also identified a "pan-viral" factor of importance for each of the three viruses considered in this study. We have identified a set of genes associated with this pan-viral factor, of interest for early detection of such viruses based upon the host response, as quantified via gene-expression data.

Ebola virus vaccines: an overview of current approaches

Science.gov (United States)

Marzi, Andrea; Feldmann, Heinz

2016-01-01

Ebola hemorrhagic fever is one of the most fatal viral diseases worldwide affecting humans and nonhuman primates. Although infections only occur frequently in Central Africa, the virus has the potential to spread globally and is classified as a category A pathogen that could be misused as a bioterrorism agent. As of today there is no vaccine or treatment licensed to counteract Ebola virus infections. DNA, subunit and several viral vector approaches, replicating and non-replicating, have been tested as potential vaccine platforms and their protective efficacy has been evaluated in nonhuman primate models for Ebola virus infections, which closely resemble disease progression in humans. Though these vaccine platforms seem to confer protection through different mechanisms, several of them are efficacious against lethal disease in nonhuman primates attesting that vaccination against Ebola virus infections is feasible. PMID:24575870

Protection of chickens against H5N1 highly pathogenic avian influenza virus infection by live vaccination with infectious laryngotracheitis virus recombinants expressing H5 hemagglutinin and N1 neuraminidase.

Science.gov (United States)

Pavlova, Sophia P; Veits, Jutta; Keil, Günther M; Mettenleiter, Thomas C; Fuchs, Walter

2009-01-29

Attenuated vaccine strains of the alphaherpesvirus causing infectious laryngotracheitis of chickens (ILTV, gallid herpesvirus 1) can be used for mass application. Previously, we showed that live virus vaccination with recombinant ILTV expressing hemagglutinin of highly pathogenic avian influenza viruses (HPAIV) protected chickens against ILT and fowl plague caused by HPAIV carrying the corresponding hemagglutinin subtypes [Lüschow D, Werner O, Mettenleiter TC, Fuchs W. Protection of chickens from lethal avian influenza A virus infection by live-virus vaccination with infectious laryngotracheitis virus recombinants expressing the hemagglutinin (H5) gene. Vaccine 2001;19(30):4249-59; Veits J, Lüschow D, Kindermann K, Werner O, Teifke JP, Mettenleiter TC, et al. Deletion of the non-essential UL0 gene of infectious laryngotracheitis (ILT) virus leads to attenuation in chickens, and UL0 mutants expressing influenza virus haemagglutinin (H7) protect against ILT and fowl plague. J Gen Virol 2003;84(12):3343-52]. However, protection against H5N1 HPAIV was not satisfactory. Therefore, a newly designed dUTPase-negative ILTV vector was used for rapid insertion of the H5-hemagglutinin, or N1-neuraminidase genes of a recent H5N1 HPAIV isolate. Compared to our previous constructs, protein expression was considerably enhanced by insertion of synthetic introns downstream of the human cytomegalovirus immediate-early promoter within the 5'-nontranslated region of the transgenes. Deletion of the viral dUTPase gene did not affect in vitro replication of the ILTV recombinants, but led to sufficient attenuation in vivo. After a single ocular immunization, all chickens developed H5- or N1-specific serum antibodies. Nevertheless, animals immunized with N1-ILTV died after subsequent H5N1 HPAIV challenge, although survival times were prolonged compared to non-vaccinated controls. In contrast, all chickens vaccinated with either H5-ILTV alone, or H5- and N1-ILTV simultaneously, survived

Infection of neuroblastoma cells by rabies virus is modulated by the virus titer.

Science.gov (United States)

Fuoco, Natalia Langenfeld; Dos Ramos Silva, Sandriana; Fernandes, Elaine Raniero; Luiz, Fernanda Guedes; Ribeiro, Orlando Garcia; Katz, Iana Suly Santos

2018-01-01

Rabies is a lethal viral infection that can affect almost all mammals, including humans. To better understand the replication of Rabies lyssavirus, we investigated if the viral load in brains naturally infected with rabies influences viral internalization and viral growth kinetics in neuroblastoma cells, and if the viral load affects mortality in mice after intradermal infection. We noted that high initial viral loads in brains (group II) were unfavourable for increasing viral titers during serial passages in neuroblastoma cells when compared to low initial viral loads in brains (group I). In addition, group I strains showed higher viral growth and enhanced internalization efficiency in neuroblastoma cells than group II strains. However, we observed that the dominant virus subpopulation in group II promoted efficient viral infection in the central nervous system in the new host, providing a selective advantage to the virus. Our data indicate that rabies infection in animal models depends on not only the virus strain but also the amount of virus. This study may serve as a basis for understanding the biologic proprieties of Rabies lyssavirus strains with respect to the effects on viral replication and the impact on pathogenesis, improving virus yields for use in vaccine development. Copyright © 2017 Elsevier B.V. All rights reserved.

Lethal and sub-lethal effects of five pesticides used in rice farming on the earthworm Eisenia fetida

NARCIS (Netherlands)

Rico, Andreu; Sabater, Consuelo; Castillo, María Ángeles

2016-01-01

The toxicity of five pesticides typically used in rice farming (trichlorfon, dimethoate, carbendazim, tebuconazole and prochloraz) was evaluated on different lethal and sub-lethal endpoints of the earthworm Eisenia fetida. The evaluated endpoints included: avoidance behaviour after an exposure

Lethal Epistaxis.

Science.gov (United States)

Byard, Roger W

2016-09-01

Epistaxis or nosebleed refers to bleeding from the nostrils, nasal cavity, or nasopharynx. Occasional cases may present with torrential lethal hemorrhage. Three cases are reported to demonstrate particular features: Case 1: A 51-year-old woman with lethal epistaxis with no obvious bleeding source; Case 2: A 77-year-old man with treated nasopharyngeal carcinoma who died from epistaxis arising from a markedly neovascularized tumor bed; Case 3: A 2-year-old boy with hemophilia B who died from epistaxis with airway obstruction in addition to gastrointestinal bleeding. Epistaxis may be associated with trauma, tumors, vascular malformations, bleeding diatheses, infections, pregnancy, endometriosis, and a variety of different drugs. Careful dissection of the nasal cavity is required to locate the site of hemorrhage and to identify any predisposing conditions. This may be guided by postmortem computerized tomographic angiography (PCTA). Despite careful dissection, however, a source of bleeding may never be identified. © 2016 American Academy of Forensic Sciences.

Kallistatin Ameliorates Influenza Virus Pathogenesis by Inhibition of Kallikrein-Related Peptidase 1-Mediated Cleavage of Viral Hemagglutinin

Science.gov (United States)

Leu, Chia-Hsing; Yang, Mei-Lin; Chung, Nai-Hui; Huang, Yen-Jang; Su, Yu-Chu; Chen, Yi-Cheng; Lin, Chia-Cheng; Shieh, Gia-Shing; Chang, Meng-Ya; Wang, Shainn-Wei; Chang, Yao; Chao, Julie; Chao, Lee

2015-01-01

Proteolytic cleavage of the hemagglutinin (HA) of influenza virus by host trypsin-like proteases is required for viral infectivity. Some serine proteases are capable of cleaving influenza virus HA, whereas some serine protease inhibitors (serpins) inhibit the HA cleavage in various cell types. Kallikrein-related peptidase 1 (KLK1, also known as tissue kallikrein) is a widely distributed serine protease. Kallistatin, a serpin synthesized mainly in the liver and rapidly secreted into the circulation, forms complexes with KLK1 and inhibits its activity. Here, we investigated the roles of KLK1 and kallistatin in influenza virus infection. We show that the levels of KLK1 increased, whereas those of kallistatin decreased, in the lungs of mice during influenza virus infection. KLK1 cleaved H1, H2, and H3 HA molecules and consequently enhanced viral production. In contrast, kallistatin inhibited KLK1-mediated HA cleavage and reduced viral production. Cells transduced with the kallistatin gene secreted kallistatin extracellularly, which rendered them more resistant to influenza virus infection. Furthermore, lentivirus-mediated kallistatin gene delivery protected mice against lethal influenza virus challenge by reducing the viral load, inflammation, and injury in the lung. Taking the data together, we determined that KLK1 and kallistatin contribute to the pathogenesis of influenza virus by affecting the cleavage of the HA peptide and inflammatory responses. This study provides a proof of principle for the potential therapeutic application of kallistatin or other KLK1 inhibitors for influenza. Since proteolytic activation also enhances the infectivity of some other viruses, kallistatin and other kallikrein inhibitors may be explored as antiviral agents against these viruses. PMID:26149981

Induction of complex immune responses and strong protection against retrovirus challenge by adenovirus-based immunization depends on the order of vaccine delivery.

Science.gov (United States)

Kaulfuß, Meike; Wensing, Ina; Windmann, Sonja; Hrycak, Camilla Patrizia; Bayer, Wibke

2017-02-06

In the Friend retrovirus mouse model we developed potent adenovirus-based vaccines that were designed to induce either strong Friend virus GagL 85-93 -specific CD8 + T cell or antibody responses, respectively. To optimize the immunization outcome we evaluated vaccination strategies using combinations of these vaccines. While the vaccines on their own confer strong protection from a subsequent Friend virus challenge, the simple combination of the vaccines for the establishment of an optimized immunization protocol did not result in a further improvement of vaccine effectivity. We demonstrate that the co-immunization with GagL 85-93 /leader-gag encoding vectors together with envelope-encoding vectors abrogates the induction of GagL 85-93 -specific CD8 + T cells, and in successive immunization protocols the immunization with the GagL 85-93 /leader-gag encoding vector had to precede the immunization with an envelope encoding vector for the efficient induction of GagL 85-93 -specific CD8 + T cells. Importantly, the antibody response to envelope was in fact enhanced when the mice were adenovirus-experienced from a prior immunization, highlighting the expedience of this approach. To circumvent the immunosuppressive effect of envelope on immune responses to simultaneously or subsequently administered immunogens, we developed a two immunizations-based vaccination protocol that induces strong immune responses and confers robust protection of highly Friend virus-susceptible mice from a lethal Friend virus challenge.

Expression of H5 hemagglutinin vaccine antigen in common duckweed (Lemna minor) protects against H5N1 high pathogenicity avian influenza virus challenge in immunized chickens.

Science.gov (United States)

Bertran, Kateri; Thomas, Colleen; Guo, Xuan; Bublot, Michel; Pritchard, Nikki; Regan, Jeffrey T; Cox, Kevin M; Gasdaska, John R; Dickey, Lynn F; Kapczynski, Darrell R; Swayne, David E

2015-07-09

A synthetic hemagglutinin (HA) gene from the highly pathogenic avian influenza (HPAI) virus A/chicken/Indonesia/7/2003 (H5N1) (Indo/03) was expressed in aquatic plant Lemna minor (rLemna-HA). In Experiment 1, efficacy of rLemna-HA was tested on birds immunized with 0.2μg or 2.3 μg HA and challenged with 10(6) mean chicken embryo infectious doses (EID50) of homologous virus strain. Both dosages of rLemna-HA conferred clinical protection and dramatically reduced viral shedding. Almost all the birds immunized with either dosage of rLemna-HA elicited HA antibody titers against Indo/03 antigen, suggesting an association between levels of anti-Indo/03 antibodies and protection. In Experiment 2, efficacy of rLemna-HA was tested on birds immunized with 0.9 μg or 2.2 μg HA and challenged with 10(6) EID50 of heterologous H5N1 virus strains A/chicken/Vietnam/NCVD-421/2010 (VN/10) or A/chicken/West Java/PWT-WIJ/2006 (PWT/06). Birds challenged with VN/10 exhibited 100% survival regardless of immunization dosage, while birds challenged with PWT/06 had 50% and 30% mortality at 0.9 μg HA and 2.2 μg HA, respectively. For each challenge virus, viral shedding titers from 2.2 μg HA vaccinated birds were significantly lower than those from 0.9μg HA vaccinated birds, and titers from both immunized groups were in turn significantly lower than those from sham vaccinated birds. Even if immunized birds elicited HA titers against the vaccine antigen Indo/03, only the groups challenged with VN/10 developed humoral immunity against the challenge antigen. None (rLemna-HA 0.9 μg HA) and 40% (rLemna-HA 2.2 μg HA) of the immunized birds challenged with PWT/06 elicited pre-challenge antibody titers, respectively. In conclusion, Lemna-expressed HA demonstrated complete protective immunity against homologous challenge and suboptimal protection against heterologous challenge, the latter being similar to results from inactivated whole virus vaccines. Transgenic duckweed-derived HA could be a

A novel small molecule inhibitor of influenza A viruses that targets polymerase function and indirectly induces interferon.

Directory of Open Access Journals (Sweden)

Mila Brum Ortigoza

Full Text Available Influenza viruses continue to pose a major public health threat worldwide and options for antiviral therapy are limited by the emergence of drug-resistant virus strains. The antiviral cytokine, interferon (IFN is an essential mediator of the innate immune response and influenza viruses, like many viruses, have evolved strategies to evade this response, resulting in increased replication and enhanced pathogenicity. A cell-based assay that monitors IFN production was developed and applied in a high-throughput compound screen to identify molecules that restore the IFN response to influenza virus infected cells. We report the identification of compound ASN2, which induces IFN only in the presence of influenza virus infection. ASN2 preferentially inhibits the growth of influenza A viruses, including the 1918 H1N1, 1968 H3N2 and 2009 H1N1 pandemic strains and avian H5N1 virus. In vivo, ASN2 partially protects mice challenged with a lethal dose of influenza A virus. Surprisingly, we found that the antiviral activity of ASN2 is not dependent on IFN production and signaling. Rather, its IFN-inducing property appears to be an indirect effect resulting from ASN2-mediated inhibition of viral polymerase function, and subsequent loss of the expression of the viral IFN antagonist, NS1. Moreover, we identified a single amino acid mutation at position 499 of the influenza virus PB1 protein that confers resistance to ASN2, suggesting that PB1 is the direct target. This two-pronged antiviral mechanism, consisting of direct inhibition of virus replication and simultaneous activation of the host innate immune response, is a unique property not previously described for any single antiviral molecule.

Experimental infection of Artibeus intermedius with a vampire bat rabies virus.

Science.gov (United States)

Obregón-Morales, Cirani; Aguilar-Setién, Álvaro; Perea Martínez, Leonardo; Galvez-Romero, Guillermo; Martínez-Martínez, Flor Olivia; Aréchiga-Ceballos, Nidia

2017-06-01

Experimental infection of Artibeus intermedius, the great fruit-eating bat, was performed with vampire bat rabies isolates. Bats (n=35) were captured in the wild and quarantined prior to experimental infection. No rabies antibodies were detected by rapid fluorescent focus inhibition test (RFFIT) prior to infection. Three doses of rabies virus (RV) and three different routes of infection were used. One out of 35 bats died without showing any clinical signs at day 14 and was positive for rabies. None of the 34 other bats showed clinical signs for rabies, but high antibody titers were detected post-inoculation, suggesting either innate immune response to the vampire bat rabies virus or possible pre-exposure to RV and inoculation leading to a booster effect. Rabies virus was detected by hemi-nested RT-PCR (hnRT-PCR) in the brain (n=3), stomach (n=1) of bats that were negative by immunofluorescence and that survived rabies infection. The bat that died on day 14 was positive by hnRT-PCR on the brain, heart and liver. These results suggest that either previous non-lethal exposure to RV or natural low susceptibility to vampire bat viruses somehow protected Artibeus intermedius from clinical rabies infection leading to a marginal lethality effect on this bats species population in the wild. Copyright © 2017 Elsevier Ltd. All rights reserved.

Vesicular stomatitis virus-based ebola vaccine is well-tolerated and protects immunocompromised nonhuman primates.

Directory of Open Access Journals (Sweden)

Thomas W Geisbert

2008-11-01

Full Text Available Ebola virus (EBOV is a significant human pathogen that presents a public health concern as an emerging/re-emerging virus and as a potential biological weapon. Substantial progress has been made over the last decade in developing candidate preventive vaccines that can protect nonhuman primates against EBOV. Among these prospects, a vaccine based on recombinant vesicular stomatitis virus (VSV is particularly robust, as it can also confer protection when administered as a postexposure treatment. A concern that has been raised regarding the replication-competent VSV vectors that express EBOV glycoproteins is how these vectors would be tolerated by individuals with altered or compromised immune systems such as patients infected with HIV. This is especially important as all EBOV outbreaks to date have occurred in areas of Central and Western Africa with high HIV incidence rates in the population. In order to address this concern, we evaluated the safety of the recombinant VSV vector expressing the Zaire ebolavirus glycoprotein (VSVDeltaG/ZEBOVGP in six rhesus macaques infected with simian-human immunodeficiency virus (SHIV. All six animals showed no evidence of illness associated with the VSVDeltaG/ZEBOVGP vaccine, suggesting that this vaccine may be safe in immunocompromised populations. While one goal of the study was to evaluate the safety of the candidate vaccine platform, it was also of interest to determine if altered immune status would affect vaccine efficacy. The vaccine protected 4 of 6 SHIV-infected macaques from death following ZEBOV challenge. Evaluation of CD4+ T cells in all animals showed that the animals that succumbed to lethal ZEBOV challenge had the lowest CD4+ counts, suggesting that CD4+ T cells may play a role in mediating protection against ZEBOV.

Monovalent Virus-Like Particle Vaccine Protects Guinea Pigs and Nonhuman Primates Against Infection with Multiple Marburg Viruses

National Research Council Canada - National Science Library

Swenson, Dana L; Warfield, Kelly L; Larsen, Tom; Alves, D. A; Coberley, Sadie S; Bavari, Sina

2008-01-01

.... Guinea pigs vaccinated with marburgvirus (m)VLPs or inactivated MARV (iMARV) develop homologous humoral and T cell responses and are completely protected from a lethal homologous MARV challenge...

A comparative study of proliferative nodules and lethal melanomas in congenital nevi from children.

Science.gov (United States)

Yélamos, Oriol; Arva, Nicoleta C; Obregon, Roxana; Yazdan, Pedram; Wagner, Annette; Guitart, Joan; Gerami, Pedram

2015-03-01

Differentiating proliferative nodules (PNs) from melanomas arising in congenital nevi (CN) is a considerable challenge for dermatopathologists. Most of the specimens dermatopathologists assess that deal with this differential diagnosis involve proliferations of melanocytes arising in the dermis. In this study, we compare the clinical, histologic, and molecular findings of these 2 conditions. In our database, we found 22 examples of PNs arising in the dermis of CN and 2 cases of lethal melanomas arising from the dermis/epidermis of CN of children. Importantly, we found that among dermal melanocytic proliferations arising from CN in children, PNs are far more common than lethal melanomas. Clinically, multiplicity of lesions favored a diagnosis of PNs, whereas ulceration was infrequent in PNs compared with lethal melanomas. Histologically, PNs showed several distinct patterns including expansile nodules of epithelioid melanocytes with mitotic counts lower than that seen in the melanomas (1.67 vs. 12.5 mitoses/mm), a small round blue cell pattern often highly mitotically active, neurocristic-like, blue nevus-like, a nevoid melanoma-like pattern, or an undifferentiated spindle cell pattern. The lethal melanomas both featured expansile nodules of epithelioid melanocytes with high mitotic counts (range, 5 to 20 mitoses/mm) and an ulcerated overlying epidermis. At the molecular level, the PNs showed mostly whole chromosomal copy number aberrations, which in some cases were accompanied by rare partial chromosomal aberrations, whereas both lethal melanomas showed highly elevated copy number aberrations involving 6p25 without gains of the long arm of chromosome 6.

Enhanced Efficacy of a Codon-Optimized DNA Vaccine Encoding the Glycoprotein Precursor Gene of Lassa Virus in a Guinea Pig Disease Model When Delivered by Dermal Electroporation

Directory of Open Access Journals (Sweden)

Niranjan Y. Sardesai

2013-07-01

Full Text Available Lassa virus (LASV causes a severe, often fatal, hemorrhagic fever endemic to West Africa. Presently, there are no FDA-licensed medical countermeasures for this disease. In a pilot study, we constructed a DNA vaccine (pLASV-GPC that expressed the LASV glycoprotein precursor gene (GPC. This plasmid was used to vaccinate guinea pigs (GPs using intramuscular electroporation as the delivery platform. Vaccinated GPs were protected from lethal infection (5/6 with LASV compared to the controls. However, vaccinated GPs experienced transient viremia after challenge, although lower than the mock-vaccinated controls. In a follow-on study, we developed a new device that allowed for both the vaccine and electroporation pulse to be delivered to the dermis. We also codon-optimized the GPC sequence of the vaccine to enhance expression in GPs. Together, these innovations resulted in enhanced efficacy of the vaccine. Unlike the pilot study where neutralizing titers were not detected until after virus challenge, modest neutralizing titers were detected in guinea pigs before challenge, with escalating titers detected after challenge. The vaccinated GPs were never ill and were not viremic at any timepoint. The combination of the codon-optimized vaccine and dermal electroporation delivery is a worthy candidate for further development.

Immunoenzymetic test-system for determination of antibodies to the hepatitis C virus

International Nuclear Information System (INIS)

Abdukayumov, A. M.; Chistyakov, P. G.; Garayshina, G. R.

2001-01-01

Interest to the study of different aspects of Hepetitis C is defined first of all by its wide spreadness. According to rated data there are infected HCV not less than 5 hundred million persons in the world. It reaches 10,1% of the whole human population /1/. Annually about 8 - 10 thousand lethal cases are connected with chronic HCV infection. Exactly HCV infection is one of the main reasons for the whole group of the chronic liver problems - a chronic hepatitis, cirrhosis and anothers. In spite of the significant progress in the study of hepatitis C, Hepetitis C virus is mysterious virus. It was not understood the HC pathogenes completely what would explained a possibility of lethal cases after 25 years after infection. The offered method ensures high specificity of the analysis. In the Table 1 are represented the comparative data for the test-systems different origin

Detection of Ebola Virus RNA through Aerosol Sampling of Animal Biosafety Level 4 Rooms Housing Challenged Nonhuman Primates

Science.gov (United States)

2016-08-02

Rooms Housing Challenged Nonhuman Primates 10 11 12 13 14 15 David E. Harbourt1*, Sara C. Johnston1, James Pettitt2, Travis K. Warren1 and...Sampling of ABSL-4 Rooms Housing Challenged Nonhuman 10 Primates for publication in an edition of The Journal of Infectious Disease. This 11 manuscript...embedded in the texts. This is the first report demonstrating detection of Ebola virus 17 RNA from animal rooms housing infected nonhuman primates and

Physician use of updated anti-virus software in a tertiary Nigerian ...

African Journals Online (AJOL)

While physicians are becoming increasingly dependent on computers and the internet, highly lethal malware continue to be loaded into cyberspace. We sought to assess the proportion of physicians with updated anti-virus software in Jos University Teaching Hospital Nigeria and to determine perceived barriers to getting ...

The dengue virus type 2 envelope protein fusion peptide is essential for membrane fusion

International Nuclear Information System (INIS)

Huang, Claire Y.-H.; Butrapet, Siritorn; Moss, Kelly J.; Childers, Thomas; Erb, Steven M.; Calvert, Amanda E.; Silengo, Shawn J.; Kinney, Richard M.; Blair, Carol D.; Roehrig, John T.

2010-01-01

The flaviviral envelope (E) protein directs virus-mediated membrane fusion. To investigate membrane fusion as a requirement for virus growth, we introduced 27 unique mutations into the fusion peptide of an infectious cDNA clone of dengue 2 virus and recovered seven stable mutant viruses. The fusion efficiency of the mutants was impaired, demonstrating for the first time the requirement for specific FP AAs in optimal fusion. Mutant viruses exhibited different growth kinetics and/or genetic stabilities in different cell types and adult mosquitoes. Virus particles could be recovered following RNA transfection of cells with four lethal mutants; however, recovered viruses could not re-infect cells. These viruses could enter cells, but internalized virus appeared to be retained in endosomal compartments of infected cells, thus suggesting a fusion blockade. Mutations of the FP also resulted in reduced virus reactivity with flavivirus group-reactive antibodies, confirming earlier reports using virus-like particles.

Inhibition of severe acute respiratory syndrome coronavirus replication in a lethal SARS-CoV BALB/c mouse model by stinging nettle lectin, Urtica dioica agglutinin

Science.gov (United States)

Kumaki, Yohichi; Wandersee, Miles K.; Smith, Aaron J.; Zhou, Yanchen; Simmons, Graham; Nelson, Nathan M.; Bailey, Kevin W.; Vest, Zachary G.; Li, Joseph K.-K.; Chan, Paul Kay-Sheung; Smee, Donald F.; Barnard, Dale L.

2011-01-01

Urtica dioica agglutinin (UDA) is a small plant monomeric lectin, 8.7 kDa in size, with an N-acetylglucosamine specificity that inhibits viruses from Nidovirales in vitro. In the current study, we first examined the efficacy of UDA on the replication of different SARS-CoV strains in Vero 76 cells. UDA inhibited virus replication in a dose-dependent manner and reduced virus yields of the Urbani strain by 90% at 1.1 ± 0.4 µg/ml in Vero 76 cells. Then, UDA was tested for efficacy in a lethal SARS-CoV-infected BALB/c mouse model. BALB/c mice were infected with two LD50 (575 PFU) of virus for 4 hours before the mice were treated intraperitoneally with UDA at 20, 10, 5 or 0 mg/kg/day for 4 days. Treatment with UDA at 5 mg/kg significantly protected the mice against a lethal infection with mouse-adapted SARS-CoV (p<0.001), but did not significantly reduce virus lung titers. All virus-infected mice receiving UDA treatments were also significantly protected against weight loss (p<0.001). UDA also effectively reduced lung pathology scores. At day 6 after virus exposure, all groups of mice receiving UDA had much lower lung weights than did the placebo-treated mice. Thus, our data suggest that UDA treatment of SARS infection in mice leads to a substantial therapeutic effect that protects mice against death and weight loss. Furthermore, the mode of action of UDA in vitro was further investigated using live SARS-CoV Urbani strain virus and retroviral particles pseudotyped with SARS-CoV spike (S). UDA specifically inhibited the replication of live SARS-CoV or SARS-CoV pseudotyped virus when added just before, but not after, adsorption. These data suggested that UDA likely inhibits SARS-CoV infection by targeting early stages of the replication cycle, namely, adsorption or penetration. In addition, we demonstrated that UDA neutralizes the virus infectivity, presumably by binding to the SARS-CoV spike (S) glycoprotein. Finally, the target molecule for inhibition of virus

Genetic variant of canine distemper virus from clinical cases in ...

African Journals Online (AJOL)

Canine distemper virus (CDV) is a highly contagious viral pathogen of worldwide distribution that can cause lethal disease in domestic dogs and other members of the family Canidae. Genetic diversity is found among reference strains and isolates of CDV, mainly in the haemagglutinin (H) protein, and this may be ...

Lethal congenital contracture syndrome (LCCS) and other lethal arthrogryposes in Finland--an epidemiological study.

Science.gov (United States)

Pakkasjärvi, Niklas; Ritvanen, Annukka; Herva, Riitta; Peltonen, Leena; Kestilä, Marjo; Ignatius, Jaakko

2006-09-01

Arthrogryposis multiplex congenita is a heterogeneous group of disorders characterized by multiple contractures with an estimated frequency of 1 in 3,000 births. With improving diagnostic methods, increasing numbers of fetuses with arthrogryposis are found. The pathogenetic mechanisms are relatively well known but the epidemiology and genetics of the prenatally lethal forms of arthrogryposis are less well known. In this study we collected all cases of a multiple contractures diagnosed in Finland during 1987-2002 including live born infants, stillbirths, and terminated pregnancies. Ninety-two cases of 214 suffered intrauterine demise (68 selective pregnancy terminations and 24 stillbirths) and 58 died in infancy. In 141 out of these cases the diagnosis could be included within lethal arthrogryposes, with a prevalence of 1 in 6,985 (1.43/10,000) births. Of these, 59 had spinal cord pathology at autopsy and thus were of neurogenic origin. Thirty-nine cases had lethal congenital contracture syndrome (LCCS) clinically characterized by total immobility of the fetus at all ultrasound examinations (12 weeks or later), multiple joint contractures in both upper and lower limbs, hydrops, and fetal death before the 32nd week of pregnancy. LCCS is noted as a unique Finnish disorder with a prevalence of 1 in 25,250 (0.40/10,000) births and is a major cause of lethal arthrogryposis in Finland.

Modeling Powassan virus infection in Peromyscus leucopus, a natural host.

Directory of Open Access Journals (Sweden)

Luwanika Mlera

2017-01-01

Full Text Available The tick-borne flavivirus, Powassan virus (POWV causes life-threatening encephalitis in humans in North America and Europe. POWV is transmitted by ixodid tick vectors that feed on small to medium-sized mammals, such as Peromyscus leucopus mice, which may serve as either reservoir, bridge or amplification hosts. Intraperitoneal and intracranial inoculation of 4-week old Peromyscus leucopus mice with 103 PFU of POWV did not result in overt clinical signs of disease. However, following intracranial inoculation, infected mice seroconverted to POWV and histopathological examinations revealed that the mice uniformly developed mild lymphocytic perivascular cuffing and microgliosis in the brain and spinal cord from 5 to 15 days post infection (dpi, suggesting an early inflammatory response. In contrast, intracranial inoculation of 4-week old C57BL/6 and BALB/c mice was lethal by 5 dpi. Intraperitoneal inoculation was lethal in BALB/c mice, but 40% (2/5 of C57BL/6 mice survived. We concluded that Peromyscus leucopus mice infected i.c. with a lethal dose of POWV support a limited infection, restricted to the central nervous system and mount an antibody response to the virus. However, they fail to develop clinical signs of disease and are able to control the infection. These results suggest the involvement of restriction factors, and the mechanism by which Peromyscus leucopus mice restrict POWV infection remains under study.

Heterogeneity within the hemagglutinin genes of canine distemper virus (CDV) strains detected in Italy

DEFF Research Database (Denmark)

Martella, V.; Cirone, F.; Elia, G.

2006-01-01

Canine distemper virus (CDV) is a highly contagious viral pathogen causing lethal disease in dogs and other mammalians. A high degree of genetic variation is found between recent CDV strains and the old CDV isolates used in the vaccines and such genetic variation is regarded as a possible cause....... These results suggest that at least three different CDV lineages are present in Italy. Keywords: Canine distemper virus; Dogs; Lineages; H gene...

Efficacy of a high potency O1 Manisa monovalent vaccine against heterologous challenge with foot-and-mouth disease virus of O/SEA/Mya-98 lineage in sheep.

Science.gov (United States)

Singanallur, N B; Pacheco, J M; Arzt, J; Stenfeldt, C; Fosgate, G T; Rodriguez, L; Vosloo, W

2017-09-01

Potency tests for commercial oil-adjuvanted foot-and-mouth disease (FMD) vaccines are usually carried out in cattle, using a full dose (2 ml) of vaccine and homologous virus challenge. However, in sheep the recommended vaccine dose is half of the cattle dose (1 ml) and most vaccines have not been potency tested for this species, especially with heterologous viruses. To determine the efficacy of a high potency (>6PD 50 ) FMD virus (FMDV) O1Manisa vaccine in sheep, we carried out a study using a heterologous FMDV (FMDV O/SKR/2010 - Mya-98 strain) challenge. Groups of seven animals each were vaccinated with 2×, 1×, 1/2× or 1/4× dose (2 ml, 1 ml, 0.5 ml or 0.25 ml respectively) and challenged at 7 days post vaccination (dpv). Only 3 of the 7 sheep in the group vaccinated with 2 ml were protected. With 2 additional groups, receiving double or single doses and challenged at 14 dpv, 4 of 7 sheep were protected in each group. None of the sheep had measurable neutralising antibodies against the vaccine or challenge virus at 7 dpv. However, all vaccinated animals challenged at 14 dpv had a homologous neutralising response against FMDV O1 Manisa on the day of challenge and all but one animal also had a heterologous response to FMDV O/SKR/2010. Infectious FMDV and viral RNA could be found in nasal swabs between 1 and 6 days post challenge (dpc) in most vaccinated sheep, but those vaccinated with higher doses or challenged at 14 dpv showed significant decreases in the level of FMDV detection. Intermittent virus shedding was noticed between 1 and 35 dpc in all vaccinated groups, but persistent infection could be demonstrated only in 4 sheep (20%). This study showed that at the recommended dose, a high potency (>6 PD 50 ) FMDV O1Manisa vaccine does not protect sheep against a heterologous challenge at 7 dpv. However, partial protection was observed when a double dose was used at 7 dpv or when double or single dose vaccinated sheep were challenged at 14 dpv. Copyright �

Evaluation of a rapid immunodiagnostic test kit for rabies virus.

Science.gov (United States)

Kang, BoKyu; Oh, JinSik; Lee, ChulSeung; Park, Bong-Kyun; Park, YoungNam; Hong, KyungSoo; Lee, KyungGi; Cho, ByungKi; Song, DaeSub

2007-10-01

A rapid immunodiagnostic test kit for rabies virus detection was evaluated using 51 clinical samples and 4 isolates of rabies virus. The quick detection of rabies virus under field conditions may be helpful in determining if post-exposure prophylaxis is needed, thereby avoiding unnecessary treatments, as well as undue economic burden. There are several widely used diagnostic methods for rabies, including fluorescent antibody tests, reverse transcription polymerase chain reaction, and electron microscopy; however, these methods include time-consuming, intricate, and costly procedures. The rapid immunodiagnostic test was able to detect rabies virus in clinical samples, including brain tissue and saliva, in addition to 10(3.2) 50% lethal dose (LD(50))/mL cell-adapted rabies virus. The assay was not cross-reactive with non-rabies virus microbes. When the performance of the rapid immunodiagnostic test was compared to a fluorescent antibody test, the rapid immunodiagnostic test had a sensitivity of 91.7% and specificity of 100% (95.8% CI).

APOBEC3G-induced hypermutation of human immunodeficiency virus type-1 is typically a discrete "all or nothing" phenomenon

DEFF Research Database (Denmark)

Armitage, Andrew E; Deforche, Koen; Chang, Chih-Hao

2012-01-01

The rapid evolution of Human Immunodeficiency Virus (HIV-1) allows studies of ongoing host-pathogen interactions. One key selective host factor is APOBEC3G (hA3G) that can cause extensive and inactivating Guanosine-to-Adenosine (G-to-A) mutation on HIV plus-strand DNA (termed hypermutation). HIV...... can inhibit this innate anti-viral defense through binding of the viral protein Vif to hA3G, but binding efficiency varies and hypermutation frequencies fluctuate in patients. A pivotal question is whether hA3G-induced G-to-A mutation is always lethal to the virus or if it may occur at sub......-lethal frequencies that could increase viral diversification. We show in vitro that limiting-levels of hA3G-activity (i.e. when only a single hA3G-unit is likely to act on HIV) produce hypermutation frequencies similar to those in patients and demonstrate in silico that potentially non-lethal G-to-A mutation rates...

Experimental Challenge of a Peridomestic Avian Species, European Starlings ( Sturnus vulgaris ), with Novel Influenza A H7N9 Virus from China.

Science.gov (United States)

Hall, Jeffrey S; Ip, Hon S; TeSlaa, Joshua L; Nashold, Sean W; Dusek, Robert J

2016-07-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings ( Sturnus vulgaris ) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

Experimental challenge of a peridomestic avian species, European Starlings (Sturnus vulgaris), with novel Influenza A H7N9 virus from China

Science.gov (United States)

Hall, Jeffrey S.; Ip, Hon S.; Teslaa, Joshua L.; Nashold, Sean W.; Dusek, Robert

2016-01-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings (Sturnus vulgaris) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

Reproduction and fertility in human immunodeficiency virus type-1 infection

NARCIS (Netherlands)

van Leeuwen, E.; Prins, J. M.; Jurriaans, S.; Boer, K.; Reiss, P.; Repping, S.; van der Veen, F.

2007-01-01

Human immunodeficiency virus type-1 (HIV-1) affects mostly men and women in their reproductive years. For those who have access to highly active antiretroviral therapy (HAART), the course of HIV-1 infection has shifted from a lethal to a chronic disease. As a result of this, many patients with HIV-1

[Nosocomial virus infections].

Science.gov (United States)

Eggers, H J

1986-12-01

Enveloped viruses, e.g. influenza- or varicella viruses may cause highly contagious airborne infections. Their spread is difficult to control, also in hospitals. In the case of influenza and varicella immune prophylaxis and chemotherapy/chemoprophylaxis are possible. This is of particular significance, since varicella and zoster are of increasing importance for immunocompromized patients. Diarrhea is caused to a large extent by viruses. Rotavirus infections play an important role in infancy, and are frequently acquired in the hospital. In a study on infectious gastroenteritis of infants in a hospital we were able to show that 30 percent of all rotavirus infections were of nosocomial origin. Admission of a rotavirus-excreting patient (or personnel) may start a long chain of rotavirus infections on pediatric wards. Even careful hygienic measures in the hospital can hardly prevent the spread of enterovirus infections. Such infections may be severe and lethal for newborns, as shown by us in a study on an outbreak of echovirus 11 disease on a maternity ward. We have recently obtained data on the "stickiness" of enteroviruses on human skin. This could explain essential features of the spread of enteroviruses in the population.

Identification of proteomic biomarkers predicting prostate cancer aggressiveness and lethality despite biopsy-sampling error

OpenAIRE

Shipitsin, M; Small, C; Choudhury, S; Giladi, E; Friedlander, S; Nardone, J; Hussain, S; Hurley, A D; Ernst, C; Huang, Y E; Chang, H; Nifong, T P; Rimm, D L; Dunyak, J; Loda, M

2014-01-01

Background: Key challenges of biopsy-based determination of prostate cancer aggressiveness include tumour heterogeneity, biopsy-sampling error, and variations in biopsy interpretation. The resulting uncertainty in risk assessment leads to significant overtreatment, with associated costs and morbidity. We developed a performance-based strategy to identify protein biomarkers predictive of prostate cancer aggressiveness and lethality regardless of biopsy-sampling variation. Methods: Prostatectom...

Chronic Exposure of Corals to Fine Sediments: Lethal and Sub-Lethal Impacts

Science.gov (United States)

Flores, Florita; Hoogenboom, Mia O.; Smith, Luke D.; Cooper, Timothy F.; Abrego, David; Negri, Andrew P.

2012-01-01

Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS) for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata) more than the upright branching species (Acropora millepora). The lowest sediment treatments that caused full colony mortality were 30 mg l−1 TSS (25 mg cm−2 day−1) for M. aequituberculata and 100 mg l−1 TSS (83 mg cm−2 day−1) for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue. PMID:22662225

Chronic exposure of corals to fine sediments: lethal and sub-lethal impacts.

Directory of Open Access Journals (Sweden)

Florita Flores

Full Text Available Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata more than the upright branching species (Acropora millepora. The lowest sediment treatments that caused full colony mortality were 30 mg l(-1 TSS (25 mg cm(-2 day(-1 for M. aequituberculata and 100 mg l(-1 TSS (83 mg cm(-2 day(-1 for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue.

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.

Genetic and serological typing of European infectious haematopoietic necrosis virus (IHNV) isolates

DEFF Research Database (Denmark)

Johansson, Tove; Einer-Jensen, Katja; Batts, William

2009-01-01

Infectious haematopoietic necrosis virus (IHNV) causes the lethal disease infectious haematopoietic necrosis (IHN) in juvenile salmon and trout. The nucleocapsid (N) protein gene and partial glycoprotein (G) gene (nucleotides 457 to 1061) of the European isolates IT-217A, FR-32/87, DE-DF 13/98 11...

Heterologous Protection against Asian Zika Virus Challenge in Rhesus Macaques.

Directory of Open Access Journals (Sweden)

Matthew T Aliota

2016-12-01

Full Text Available Zika virus (ZIKV; Flaviviridae, Flavivirus was declared a public health emergency of international concern by the World Health Organization (WHO in February 2016, because of the evidence linking infection with ZIKV to neurological complications, such as Guillain-Barre Syndrome in adults and congenital birth defects including microcephaly in the developing fetus. Because development of a ZIKV vaccine is a top research priority and because the genetic and antigenic variability of many RNA viruses limits the effectiveness of vaccines, assessing whether immunity elicited against one ZIKV strain is sufficient to confer broad protection against all ZIKV strains is critical. Recently, in vitro studies demonstrated that ZIKV likely circulates as a single serotype. Here, we demonstrate that immunity elicited by African lineage ZIKV protects rhesus macaques against subsequent infection with Asian lineage ZIKV.Using our recently developed rhesus macaque model of ZIKV infection, we report that the prototypical ZIKV strain MR766 productively infects macaques, and that immunity elicited by MR766 protects macaques against heterologous Asian ZIKV. Furthermore, using next generation deep sequencing, we found in vivo restoration of a putative N-linked glycosylation site upon replication in macaques that is absent in numerous MR766 strains that are widely being used by the research community. This reversion highlights the importance of carefully examining the sequence composition of all viral stocks as well as understanding how passage history may alter a virus from its original form.An effective ZIKV vaccine is needed to prevent infection-associated fetal abnormalities. Macaques whose immune responses were primed by infection with East African ZIKV were completely protected from detectable viremia when subsequently rechallenged with heterologous Asian ZIKV. Therefore, these data suggest that immunogen selection is unlikely to adversely affect the breadth of

Progress and Problems in Understanding and Managing Primary Epstein-Barr Virus Infections

Science.gov (United States)

Odumade, Oludare A.; Hogquist, Kristin A.; Balfour, Henry H.

2011-01-01

Summary: Epstein-Barr virus (EBV) is a gammaherpesvirus that infects a large fraction of the human population. Primary infection is often asymptomatic but results in lifelong infection, which is kept in check by the host immune system. In some cases, primary infection can result in infectious mononucleosis. Furthermore, when host-virus balance is not achieved, the virus can drive potentially lethal lymphoproliferation and lymphomagenesis. In this review, we describe the biology of EBV and the host immune response. We review the diagnosis of EBV infection and discuss the characteristics and pathogenesis of infectious mononucleosis. These topics are approached in the context of developing therapeutic and preventative strategies. PMID:21233512

To be or not to be alive: How recent discoveries challenge the traditional definitions of viruses and life.

Science.gov (United States)

Forterre, Patrick

2016-10-01

Three major discoveries have recently profoundly modified our perception of the viral world: molecular ecologists have shown that viral particles are more abundant than cells in natural environments; structural biologists have shown that some viruses from the three domains of life, Bacteria, Eukarya and Archaea, are evolutionarily related, and microbiologists have discovered giant viruses that rival with cells in terms of size and gene content. I discuss here the scientific and philosophical impact of these discoveries on the debates over the definition, nature (living or not), and origin of viruses. I suggest that viruses have often been considered non-living, because they are traditionally assimilated to their virions. However, the term virus describes a biological process and should integrate all aspects of the viral reproduction cycle. It is especially important to focus on the intracellular part of this cycle, the virocell, when viral information is actively expressed and reproduced, allowing the emergence of new viral genes. The virocell concept theoretically removes roadblocks that prevent defining viruses as living organisms. However, defining a "living organism" remains challenging, as indicated by the case of organelles that evolved from intracellular bacteria. To bypass this problem, I suggest considering that all biological entities that actively participate in the process of life are living. Copyright © 2016. Published by Elsevier Ltd.

Development and evaluation of a blocking enzyme-linked immunosorbent assay and virus neutralization assay to detect antibodies to viral hemorrhagic septicemia virus

Science.gov (United States)

Wilson, Anna; Goldberg, Tony; Marcquenski, Susan; Olson, Wendy; Goetz, Frederick; Hershberger, Paul; Hart, Lucas M.; Toohey-Kurth, Kathy

2014-01-01

Viral hemorrhagic septicemia virus (VHSV) is a target of surveillance by many state and federal agencies in the United States. Currently, the detection of VHSV relies on virus isolation, which is lethal to fish and indicates only the current infection status. A serological method is required to ascertain prior exposure. Here, we report two serologic tests for VHSV that are nonlethal, rapid, and species independent, a virus neutralization (VN) assay and a blocking enzyme-linked immunosorbent assay (ELISA). The results show that the VN assay had a specificity of 100% and sensitivity of 42.9%; the anti-nucleocapsid-blocking ELISA detected nonneutralizing VHSV antibodies at a specificity of 88.2% and a sensitivity of 96.4%. The VN assay and ELISA are valuable tools for assessing exposure to VHSV.

Two potential recombinant rabies vaccines expressing canine parvovirus virion protein 2 induce immunogenicity to canine parvovirus and rabies virus.

Science.gov (United States)

Luo, Jun; Shi, Hehe; Tan, Yeping; Niu, Xuefeng; Long, Teng; Zhao, Jing; Tian, Qin; Wang, Yifei; Chen, Hao; Guo, Xiaofeng

2016-08-17

Both rabies virus (RABV) and canine parvovirus (CPV) cause lethal diseases in dogs. In this study, both high egg passage Flury (HEP-Flury) strains of RABV and recombinant RABV carrying double RABV glycoprotein (G) gene were used to express the CPV virion protein 2 (VP2) gene, and were designated rHEP-VP2 and, rHEP-dG-VP2 respectively. The two recombinant RABVs maintained optimal virus titration according to their viral growth kinetics assay compared with the parental strain HEP-Flury. Western blotting indicated that G protein and VP2 were expressed in vitro. The expression of VP2 in Crandell feline kidney cells post-infection by rHEP-VP2 and rHEP-dG-VP2 was confirmed by indirect immunofluorescence assay with antibody against VP2. Immunogenicity of recombinant rabies viruses was tested in Kunming mice. Both rHEP-VP2 and rHEP-dG-VP2 induced high levels of rabies antibody compared with HEP-Flury. Mice immunized with rHEP-VP2 and rHEP-dG-VP2 both had a high level of antibodies against VP2, which can protect against CPV infection. A challenge experiment indicated that more than 80% mice immunized with recombinant RABVs survived after infection of challenge virus standard 24 (CVS-24). Together, this study showed that recombinant RABVs expressing VP2 induced protective immune responses to RABV and CPV. Therefore, rHEP-VP2 and rHEP-dG-VP2 might be potential combined vaccines for RABV and CPV. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immune protection of nonhuman primates against Ebola virus with single low-dose adenovirus vectors encoding modified GPs.

Directory of Open Access Journals (Sweden)

Nancy J Sullivan

2006-06-01

Full Text Available Ebola virus causes a hemorrhagic fever syndrome that is associated with high mortality in humans. In the absence of effective therapies for Ebola virus infection, the development of a vaccine becomes an important strategy to contain outbreaks. Immunization with DNA and/or replication-defective adenoviral vectors (rAd encoding the Ebola glycoprotein (GP and nucleoprotein (NP has been previously shown to confer specific protective immunity in nonhuman primates. GP can exert cytopathic effects on transfected cells in vitro, and multiple GP forms have been identified in nature, raising the question of which would be optimal for a human vaccine.To address this question, we have explored the efficacy of mutant GPs from multiple Ebola virus strains with reduced in vitro cytopathicity and analyzed their protective effects in the primate challenge model, with or without NP. Deletion of the GP transmembrane domain eliminated in vitro cytopathicity but reduced its protective efficacy by at least one order of magnitude. In contrast, a point mutation was identified that abolished this cytopathicity but retained immunogenicity and conferred immune protection in the absence of NP. The minimal effective rAd dose was established at 10(10 particles, two logs lower than that used previously.Expression of specific GPs alone vectored by rAd are sufficient to confer protection against lethal challenge in a relevant nonhuman primate model. Elimination of NP from the vaccine and dose reductions to 10(10 rAd particles do not diminish protection and simplify the vaccine, providing the basis for selection of a human vaccine candidate.

Immune Protection of Nonhuman Primates against Ebola Virus with Single Low-Dose Adenovirus Vectors Encoding Modified GPs

Science.gov (United States)

Geisbert, Joan B; Shedlock, Devon J; Xu, Ling; Lamoreaux, Laurie; Custers, Jerome H. H. V; Popernack, Paul M; Yang, Zhi-Yong; Pau, Maria G; Roederer, Mario; Koup, Richard A; Goudsmit, Jaap; Jahrling, Peter B; Nabel, Gary J

2006-01-01

Background Ebola virus causes a hemorrhagic fever syndrome that is associated with high mortality in humans. In the absence of effective therapies for Ebola virus infection, the development of a vaccine becomes an important strategy to contain outbreaks. Immunization with DNA and/or replication-defective adenoviral vectors (rAd) encoding the Ebola glycoprotein (GP) and nucleoprotein (NP) has been previously shown to confer specific protective immunity in nonhuman primates. GP can exert cytopathic effects on transfected cells in vitro, and multiple GP forms have been identified in nature, raising the question of which would be optimal for a human vaccine. Methods and Findings To address this question, we have explored the efficacy of mutant GPs from multiple Ebola virus strains with reduced in vitro cytopathicity and analyzed their protective effects in the primate challenge model, with or without NP. Deletion of the GP transmembrane domain eliminated in vitro cytopathicity but reduced its protective efficacy by at least one order of magnitude. In contrast, a point mutation was identified that abolished this cytopathicity but retained immunogenicity and conferred immune protection in the absence of NP. The minimal effective rAd dose was established at 1010 particles, two logs lower than that used previously. Conclusions Expression of specific GPs alone vectored by rAd are sufficient to confer protection against lethal challenge in a relevant nonhuman primate model. Elimination of NP from the vaccine and dose reductions to 1010 rAd particles do not diminish protection and simplify the vaccine, providing the basis for selection of a human vaccine candidate. PMID:16683867

Inhibition of severe acute respiratory syndrome coronavirus replication in a lethal SARS-CoV BALB/c mouse model by stinging nettle lectin, Urtica dioica agglutinin.

Science.gov (United States)

Kumaki, Yohichi; Wandersee, Miles K; Smith, Aaron J; Zhou, Yanchen; Simmons, Graham; Nelson, Nathan M; Bailey, Kevin W; Vest, Zachary G; Li, Joseph K-K; Chan, Paul Kay-Sheung; Smee, Donald F; Barnard, Dale L

2011-04-01

Urtica dioica agglutinin (UDA) is a small plant monomeric lectin, 8.7 kDa in size, with an N-acetylglucosamine specificity that inhibits viruses from Nidovirales in vitro. In the current study, we first examined the efficacy of UDA on the replication of different SARS-CoV strains in Vero 76 cells. UDA inhibited virus replication in a dose-dependent manner and reduced virus yields of the Urbani strain by 90% at 1.1 ± 0.4 μg/ml in Vero 76 cells. Then, UDA was tested for efficacy in a lethal SARS-CoV-infected BALB/c mouse model. BALB/c mice were infected with two LD50 (575 PFU) of virus for 4 h before the mice were treated intraperitoneally with UDA at 20, 10, 5 or 0 mg/kg/day for 4 days. Treatment with UDA at 5 mg/kg significantly protected the mice against a lethal infection with mouse-adapted SARS-CoV (p < 0.001), but did not significantly reduce virus lung titers. All virus-infected mice receiving UDA treatments were also significantly protected against weight loss (p < 0.001). UDA also effectively reduced lung pathology scores. At day 6 after virus exposure, all groups of mice receiving UDA had much lower lung weights than did the placebo-treated mice. Thus, our data suggest that UDA treatment of SARS infection in mice leads to a substantial therapeutic effect that protects mice against death and weight loss. Furthermore, the mode of action of UDA in vitro was further investigated using live SARS-CoV Urbani strain virus and retroviral particles pseudotyped with SARS-CoV spike (S). UDA specifically inhibited the replication of live SARS-CoV or SARS-CoV pseudotyped virus when added just before, but not after, adsorption. These data suggested that UDA likely inhibits SARS-CoV infection by targeting early stages of the replication cycle, namely, adsorption or penetration. In addition, we demonstrated that UDA neutralizes the virus infectivity, presumably by binding to the SARS-CoV spike (S) glycoprotein. Finally, the target molecule for the inhibition of virus

Antiviral treatment is more effective than smallpox vaccination upon lethal monkeypox virus infection

Czech Academy of Sciences Publication Activity Database

Stittelaar, K. J.; Neyts, J.; Naesens, L.; Amerongen van, G.; Lavieren van, R. F.; Holý, Antonín; De Clercq, E.; Niesters, H. G. M.; Fries, E.; Maas, Ch.; Mulder, P. G. H.; Zeijst van der, B. A. M.; Osterhaus, D. M. E.

2006-01-01

Roč. 439, č. 7077 (2006), s. 745-748 ISSN 0028-0836 Institutional research plan: CEZ:AV0Z40550506 Keywords : monkeypox virus * vaccination * HPMPC * HPMPO-DAPy Subject RIV: CC - Organic Chemistry Impact factor: 26.681, year: 2006

Prophylactic Administration of Bacterially Derived Immunomodulators Improves the Outcome of Influenza Virus Infection in a Murine Model▿

Science.gov (United States)

Norton, Elizabeth B.; Clements, John D.; Voss, Thomas G.; Cárdenas-Freytag, Lucia

2010-01-01

Prophylactic or therapeutic immunomodulation is an antigen-independent strategy that induces nonspecific immune system activation, thereby enhancing host defense to disease. In this study, we investigated the effect of prophylactic immunomodulation on the outcome of influenza virus infection using three bacterially derived immune-enhancing agents known for promoting distinct immunological profiles. BALB/c mice were treated nasally with either cholera toxin (CT), a mutant form of the CT-related Escherichia coli heat-labile enterotoxin designated LT(R192G), or CpG oligodeoxynucleotide. Mice were subsequently challenged with a lethal dose of influenza A/PR/8/34 virus 24 h after the last immunomodulation treatment and either monitored for survival or sacrificed postchallenge for viral and immunological analysis. Treatment with the three immunomodulators prevented or delayed mortality and weight loss, but only CT and LT(R192G) significantly reduced initial lung viral loads as measured by plaque assay. Analysis performed 4 days postinfection indicated that prophylactic treatments with CT, LT(R192G), or CpG resulted in significantly increased numbers of CD4 T cells, B cells, and dendritic cells and altered costimulatory marker expression in the airways of infected mice, coinciding with reduced expression of pulmonary chemokines and the appearance of inducible bronchus-associated lymphoid tissue-like structures in the lungs. Collectively, these results suggest that, despite different immunomodulatory mechanisms, CT, LT(R192G), and CpG induce an initial inflammatory process and enhance the immune response to primary influenza virus challenge while preventing potentially damaging chemokine expression. These studies provide insight into the immunological parameters and immune modulation strategies that have the potential to enhance the nonspecific host response to influenza virus infection. PMID:20053748

A STAT-1 knockout mouse model for Machupo virus pathogenesis

Directory of Open Access Journals (Sweden)

Shurtleff Amy C

2011-06-01

Full Text Available Abstract Background Machupo virus (MACV, a member of the Arenaviridae, causes Bolivian hemorrhagic fever, with ~20% lethality in humans. The pathogenesis of MACV infection is poorly understood, and there are no clinically proven treatments for disease. This is due, in part, to a paucity of small animal models for MACV infection in which to discover and explore candidate therapeutics. Methods Mice lacking signal transducer and activator of transcription 1 (STAT-1 were infected with MACV. Lethality, viral replication, metabolic changes, hematology, histopathology, and systemic cytokine expression were analyzed throughout the course of infection. Results We report here that STAT-1 knockout mice succumbed to MACV infection within 7-8 days, and presented some relevant clinical and histopathological manifestations of disease. Furthermore, the model was used to validate the efficacy of ribavirin in protection against infection. Conclusions The STAT-1 knockout mouse model can be a useful small animal model for drug testing and preliminary immunological analysis of lethal MACV infection.

Mining of lethal recessive genetic variation in Danish cattle

DEFF Research Database (Denmark)

Das, Ashutosh

2015-01-01

in fertility. The primary objective of this PhD projekt was to identify recessive lethal gentic variants in the main Danish dairy cattle breed. Holstein-Friesian utilzing next generation sequencing (NGS) data. This study shows a potential for the use of the NGS-based reverse genetic approach in identifying...... lethal or semi-lethal recessive gentic variation...

Genetic recombination of Herpes simplex virus, the role of the host cell and UV-irradiation of the virus

International Nuclear Information System (INIS)

Dasgupta, U.B.; Summers, W.C.; Yale Univ., New Haven, CT; Yale Univ., New Haven, CT

1980-01-01

Recombination frequencies for two sets of genetic markers of Herpes simplex virus were determined in various host cells with and without ultraviolet irradiation of the virus. UV irradiation increased the recombination frequency in all the cell types studied in direct proportion to the unrepaired lethal damage. In human skin fibroblasts derived from a patient with xeroderma pigmentosum (XP) of complementation group A, a given dose of UV stimulated recombination more than that in fibroblasts from normal individuals. On the other hand, UV stimulation of HSV recombination was slightly less than normal in fibroblasts derived from a patient with a variant form XP and from an ataxia telangiectasia patient. Caffeine, an agent known to inhibit repair of UV damage, reduced recombination in most of the cell types studied but did not suppress the UV-induced increase in recombination. These findings suggest that for virus DNA with the same number of unrepaired UV-lesions, each of the tested cell types promoted HSV-recombination to an equivalent extent. (orig.) [de

Lethal canine distemper virus outbreak in cynomolgus monkeys in Japan in 2008.

Science.gov (United States)

Sakai, Kouji; Nagata, Noriyo; Ami, Yasushi; Seki, Fumio; Suzaki, Yuriko; Iwata-Yoshikawa, Naoko; Suzuki, Tadaki; Fukushi, Shuetsu; Mizutani, Tetsuya; Yoshikawa, Tomoki; Otsuki, Noriyuki; Kurane, Ichiro; Komase, Katsuhiro; Yamaguchi, Ryoji; Hasegawa, Hideki; Saijo, Masayuki; Takeda, Makoto; Morikawa, Shigeru

2013-01-01

Canine distemper virus (CDV) has recently expanded its host range to nonhuman primates. A large CDV outbreak occurred in rhesus monkeys at a breeding farm in Guangxi Province, China, in 2006, followed by another outbreak in rhesus monkeys at an animal center in Beijing in 2008. In 2008 in Japan, a CDV outbreak also occurred in cynomolgus monkeys imported from China. In that outbreak, 46 monkeys died from severe pneumonia during a quarantine period. A CDV strain (CYN07-dV) was isolated in Vero cells expressing dog signaling lymphocyte activation molecule (SLAM). Phylogenic analysis showed that CYN07-dV was closely related to the recent CDV outbreaks in China, suggesting continuing chains of CDV infection in monkeys. In vitro, CYN07-dV uses macaca SLAM and macaca nectin4 as receptors as efficiently as dog SLAM and dog nectin4, respectively. CYN07-dV showed high virulence in experimentally infected cynomolgus monkeys and excreted progeny viruses in oral fluid and feces. These data revealed that some of the CDV strains, like CYN07-dV, have the potential to cause acute systemic infection in monkeys.

Recent Perspectives on Genome, Transmission, Clinical Manifestation, Diagnosis, Therapeutic Strategies, Vaccine Developments, and Challenges of Zika Virus Research

Directory of Open Access Journals (Sweden)

Apoorva Shankar

2017-09-01

Full Text Available One of the potential threats to public health microbiology in 21st century is the increased mortality rate caused by Zika virus (ZIKV, a mosquito-borne flavivirus. The severity of ZIKV infection urged World Health Organization (WHO to declare this virus as a global concern. The limited knowledge on the structure, virulent factors, and replication mechanism of the virus posed as hindrance for vaccine development. Several vector and non-vector-borne mode of transmission are observed for spreading the disease. The similarities of the virus with other flaviviruses such as dengue and West Nile virus are worrisome; hence, there is high scope to undertake ZIKV research that probably provide insight for novel therapeutic intervention. Thus, this review focuses on the recent aspect of ZIKV research which includes the outbreak, genome structure, multiplication and propagation of the virus, current animal models, clinical manifestations, available treatment options (probable vaccines and therapeutics, and the recent advancements in computational drug discovery pipelines, challenges and limitation to undertake ZIKV research. The review suggests that the infection due to ZIKV became one of the universal concerns and an interdisciplinary environment of in vitro cellular assays, genomics, proteomics, and computational biology approaches probably contribute insights for screening of novel molecular targets for drug design. The review tried to provide cutting edge knowledge in ZIKV research with future insights required for the development of novel therapeutic remedies to curtail ZIKV infection.

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.

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.

The Ebola Virus Glycoprotein Contributes to but Is Not Sufficient for Virulence In Vivo

Science.gov (United States)

Groseth, Allison; Marzi, Andrea; Hoenen, Thomas; Herwig, Astrid; Gardner, Don; Becker, Stephan; Ebihara, Hideki; Feldmann, Heinz

2012-01-01

Among the Ebola viruses most species cause severe hemorrhagic fever in humans; however, Reston ebolavirus (REBOV) has not been associated with human disease despite numerous documented infections. While the molecular basis for this difference remains unclear, in vitro evidence has suggested a role for the glycoprotein (GP) as a major filovirus pathogenicity factor, but direct evidence for such a role in the context of virus infection has been notably lacking. In order to assess the role of GP in EBOV virulence, we have developed a novel reverse genetics system for REBOV, which we report here. Together with a previously published full-length clone for Zaire ebolavirus (ZEBOV), this provides a unique possibility to directly investigate the role of an entire filovirus protein in pathogenesis. To this end we have generated recombinant ZEBOV (rZEBOV) and REBOV (rREBOV), as well as chimeric viruses in which the glycoproteins from these two virus species have been exchanged (rZEBOV-RGP and rREBOV-ZGP). All of these viruses could be rescued and the chimeras replicated with kinetics similar to their parent virus in tissue culture, indicating that the exchange of GP in these chimeric viruses is well tolerated. However, in a mouse model of infection rZEBOV-RGP demonstrated markedly decreased lethality and prolonged time to death when compared to rZEBOV, confirming that GP does indeed contribute to the full expression of virulence by ZEBOV. In contrast, rREBOV-ZGP did not show any signs of virulence, and was in fact slightly attenuated compared to rREBOV, demonstrating that GP alone is not sufficient to confer a lethal phenotype or exacerbate disease in this model. Thus, while these findings provide direct evidence that GP contributes to filovirus virulence in vivo, they also clearly indicate that other factors are needed for the acquisition of full virulence. PMID:22876185

The Ebola virus glycoprotein contributes to but is not sufficient for virulence in vivo.

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Allison Groseth

Full Text Available Among the Ebola viruses most species cause severe hemorrhagic fever in humans; however, Reston ebolavirus (REBOV has not been associated with human disease despite numerous documented infections. While the molecular basis for this difference remains unclear, in vitro evidence has suggested a role for the glycoprotein (GP as a major filovirus pathogenicity factor, but direct evidence for such a role in the context of virus infection has been notably lacking. In order to assess the role of GP in EBOV virulence, we have developed a novel reverse genetics system for REBOV, which we report here. Together with a previously published full-length clone for Zaire ebolavirus (ZEBOV, this provides a unique possibility to directly investigate the role of an entire filovirus protein in pathogenesis. To this end we have generated recombinant ZEBOV (rZEBOV and REBOV (rREBOV, as well as chimeric viruses in which the glycoproteins from these two virus species have been exchanged (rZEBOV-RGP and rREBOV-ZGP. All of these viruses could be rescued and the chimeras replicated with kinetics similar to their parent virus in tissue culture, indicating that the exchange of GP in these chimeric viruses is well tolerated. However, in a mouse model of infection rZEBOV-RGP demonstrated markedly decreased lethality and prolonged time to death when compared to rZEBOV, confirming that GP does indeed contribute to the full expression of virulence by ZEBOV. In contrast, rREBOV-ZGP did not show any signs of virulence, and was in fact slightly attenuated compared to rREBOV, demonstrating that GP alone is not sufficient to confer a lethal phenotype or exacerbate disease in this model. Thus, while these findings provide direct evidence that GP contributes to filovirus virulence in vivo, they also clearly indicate that other factors are needed for the acquisition of full virulence.

Effect of Antiviral Agents in Equine Abortion Virus-Infected Hamsters1

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Lieberman, Melvin; Pascale, Andrea; Schafer, Thomas W.; Came, Paul E.

1972-01-01

Equine abortion virus, a member of the herpesvirus group, produces a lethal infection in hamsters. With this system, the protective effect of certain inhibitors of deoxyribonucleic acid viruses, inducers of interferon and exogenous interferon, was evaluated. Of the various agents studied, 9-β-d-arabinofuranosyladenine markedly suppressed mortality, and 5-iodo-2′-deoxyuridine, distamycin A, and N-ethylisatin β-thiosemicarbazone were inactive. Of the inducers tested, statolon, ultraviolet-irradiated Newcastle disease virus, and polyriboinosinic:polyribocytidylic acid (poly I:C) were protective, and endotoxin, polyacrylic acid, and polymethacrylic acid did not protect. Administration of exogenous interferon did not afford protection. Statolon and ultraviolet-irradiated Newcastle disease virus induced circulating interferon in hamsters, whereas poly I:C, endotoxin, and polyacrylic acid did not produce interferon. Because of the severity of the disease produced in hamsters by equine abortion virus, lack of protective activity by an agent in this system should not preclude possible efficacy against other members of the herpesvirus group. PMID:4376907

Crystal Structure of Marburg Virus VP40 Reveals a Broad, Basic Patch for Matrix Assembly and a Requirement of the N-Terminal Domain for Immunosuppression.

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Oda, Shun-Ichiro; Noda, Takeshi; Wijesinghe, Kaveesha J; Halfmann, Peter; Bornholdt, Zachary A; Abelson, Dafna M; Armbrust, Tammy; Stahelin, Robert V; Kawaoka, Yoshihiro; Saphire, Erica Ollmann

2016-02-15

Marburg virus (MARV), a member of the filovirus family, causes severe hemorrhagic fever with up to 90% lethality. MARV matrix protein VP40 is essential for assembly and release of newly copied viruses and also suppresses immune signaling in the infected cell. Here we report the crystal structure of MARV VP40. We found that MARV VP40 forms a dimer in solution, mediated by N-terminal domains, and that formation of this dimer is essential for budding of virus-like particles. We also found the N-terminal domain to be necessary and sufficient for immune antagonism. The C-terminal domains of MARV VP40 are dispensable for immunosuppression but are required for virus assembly. The C-terminal domains are only 16% identical to those of Ebola virus, differ in structure from those of Ebola virus, and form a distinct broad and flat cationic surface that likely interacts with the cell membrane during virus assembly. Marburg virus, a cousin of Ebola virus, causes severe hemorrhagic fever, with up to 90% lethality seen in recent outbreaks. Molecular structures and visual images of the proteins of Marburg virus are essential for the development of antiviral drugs. One key protein in the Marburg virus life cycle is VP40, which both assembles the virus and suppresses the immune system. Here we provide the molecular structure of Marburg virus VP40, illustrate differences from VP40 of Ebola virus, and reveal surfaces by which Marburg VP40 assembles progeny and suppresses immune function. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Challenges of influenza A viruses in humans and animals and current animal vaccines as an effective control measure

Science.gov (United States)

2018-01-01

Influenza A viruses (IAVs) are genetically diverse and variable pathogens that share various hosts including human, swine, and domestic poultry. Interspecies and intercontinental viral spreads make the ecology of IAV more complex. Beside endemic IAV infections, human has been exposed to pandemic and zoonotic threats from avian and swine influenza viruses. Animal health also has been threatened by high pathogenic avian influenza viruses (in domestic poultry) and reverse zoonosis (in swine). Considering its dynamic interplay between species, prevention and control against IAV should be conducted effectively in both humans and animal sectors. Vaccination is one of the most efficient tools against IAV. Numerous vaccines against animal IAVs have been developed by a variety of vaccine technologies and some of them are currently commercially available. We summarize several challenges in control of IAVs faced by human and animals and discuss IAV vaccines for animal use with those application in susceptible populations. PMID:29399575

Identification of proteomic biomarkers predicting prostate cancer aggressiveness and lethality despite biopsy-sampling error.

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Shipitsin, M; Small, C; Choudhury, S; Giladi, E; Friedlander, S; Nardone, J; Hussain, S; Hurley, A D; Ernst, C; Huang, Y E; Chang, H; Nifong, T P; Rimm, D L; Dunyak, J; Loda, M; Berman, D M; Blume-Jensen, P

2014-09-09

Key challenges of biopsy-based determination of prostate cancer aggressiveness include tumour heterogeneity, biopsy-sampling error, and variations in biopsy interpretation. The resulting uncertainty in risk assessment leads to significant overtreatment, with associated costs and morbidity. We developed a performance-based strategy to identify protein biomarkers predictive of prostate cancer aggressiveness and lethality regardless of biopsy-sampling variation. Prostatectomy samples from a large patient cohort with long follow-up were blindly assessed by expert pathologists who identified the tissue regions with the highest and lowest Gleason grade from each patient. To simulate biopsy-sampling error, a core from a high- and a low-Gleason area from each patient sample was used to generate a 'high' and a 'low' tumour microarray, respectively. Using a quantitative proteomics approach, we identified from 160 candidates 12 biomarkers that predicted prostate cancer aggressiveness (surgical Gleason and TNM stage) and lethal outcome robustly in both high- and low-Gleason areas. Conversely, a previously reported lethal outcome-predictive marker signature for prostatectomy tissue was unable to perform under circumstances of maximal sampling error. Our results have important implications for cancer biomarker discovery in general and development of a sampling error-resistant clinical biopsy test for prediction of prostate cancer aggressiveness.

Challenges to mapping the health risk of hepatitis A virus infection

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Wiersma Steven T

2011-10-01

Full Text Available Abstract Background World maps are among the most effective ways to convey public health messages such as recommended vaccinations, but creating a useful and valid map requires careful deliberation. The changing epidemiology of hepatitis A virus (HAV in many world regions heightens the need for up-to-date risk maps. HAV infection is usually asymptomatic in children, so low-income areas with high incidence rates usually have a low burden of disease. In higher-income areas, many adults remain susceptible to the virus and, if infected, often experience severe disease. Results Several challenges associated with presenting hepatitis A risk using maps were identified, including the need to decide whether prior infection or continued susceptibility more aptly indicates risk, whether to display incidence or prevalence, how to distinguish between different levels of risk, how to display changes in risk over time, how to present complex information to target audiences, and how to handle missing or obsolete data. Conclusion For future maps to be comparable across place and time, we propose the use of the age at midpoint of population susceptibility as a standard indicator for the level of hepatitis A endemicity within a world region. We also call for the creation of an accessible active database for population-based age-specific HAV seroprevalence and incidence studies. Health risk maps for other conditions with rapidly changing epidemiology would benefit from similar strategies.

Preclinical and Clinical Development of a YFV 17 D-Based Chimeric Vaccine against West Nile Virus

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Gustavo H. Dayan

2013-12-01

Full Text Available Substantial success has been achieved in the development and implementation of West Nile (WN vaccines for horses; however, no human WN vaccines are approved. This review focuses on the construction, pre-clinical and clinical characterization of ChimeriVax-WN02 for humans, a live chimeric vaccine composed of a yellow fever (YF 17D virus in which the prM-E envelope protein genes are replaced with the corresponding genes of the WN NY99 virus. Pre-clinical studies demonstrated that ChimeriVax-WN02 was significantly less neurovirulent than YF 17D in mice and rhesus and cynomolgus monkeys. The vaccine elicited neutralizing antibody titers after inoculation in hamsters and monkeys and protected immunized animals from lethal challenge including intracerebral inoculation of high dose of WN NY99 virus. Safety, viremia and immunogenicity of ChimeriVax-WN02 were assessed in one phase I study and in two phase II clinical trials. No safety signals were detected in the three clinical trials with no remarkable differences in incidence of adverse events (AEs between vaccine and placebo recipients. Viremia was transient and the mean viremia levels were low. The vaccine elicited strong and durable neutralizing antibody and cytotoxic T cell responses. WN epidemiology impedes a classical licensure pathway; therefore, innovative licensure strategies should be explored.

Testing the Effect of Internal Genes Derived from a Wild-Bird-Origin H9N2 Influenza A Virus on the Pathogenicity of an A/H7N9 Virus

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Wen Su

2015-09-01

Full Text Available Since 2013, avian influenza A(H7N9 viruses have diversified into multiple lineages by dynamically reassorting with other viruses, especially H9N2, in Chinese poultry. Despite concerns about the pandemic threat posed by H7N9 viruses, little is known about the biological properties of H7N9 viruses that may recruit internal genes from genetically distinct H9N2 viruses circulating among wild birds. Here, we generated 63 H7N9 reassortants derived from an avian H7N9 and a wild-bird-origin H9N2 virus. Compared with the wild-type parent, 25/63 reassortants had increased pathogenicity in mice. A reassortant containing PB1 of the H9N2 virus was highly lethal to mice and chickens but was not transmissible to guinea pigs by airborne routes; however, three substitutions associated with adaptation to mammals conferred airborne transmission to the virus. The emergence of the H7N9-pandemic reassortant virus highlights that continuous monitoring of H7N9 viruses is needed, especially at the domestic poultry/wild bird interface.

The discovery of viruses: advancing science and medicine by challenging dogma.

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Artenstein, Andrew W

2012-07-01

The discovery of viruses in the final years of the nineteenth century represented the culmination of two decades of work on tobacco mosaic disease by three botanical scientists. Eventually their discovery led to a paradigm shift in scientific thought, but it took more than 20 years to appreciate its implications because it was inconsistent with the prevailing dogma of the time-Koch's postulates. Although these 'rules' were actually conceived of as guidelines upon which to establish microbial causality and their implementation resulted in many new discoveries, they also had the unintended effect of limiting the interpretation of novel findings. However, by challenging existing dogma through rigorous scientific observation and sheer persistence, the investigators advanced medicine and heralded new areas of discovery. Copyright © 2012 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Lethality of Rendang packaged in multilayer retortable pouch with sterilization process

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Praharasti, A. S.; Kusumaningrum, A.; Frediansyah, A.; Nurhikmat, A.; Khasanah, Y.; Suprapedi

2017-01-01

Retort Pouch had become a choice to preserve foods nowadays, besides the used of the can. Both had their own advantages, and Retort Pouch became more popular for the reason of cheaper and easier to recycle. General Method usually used to estimate the lethality of commercial heat sterilization process. Lethality value wa s used for evaluating the efficacy of the thermal process. This study aimed to find whether different layers of pouch materials affect the lethality value and to find differences lethality in two types of multilayer retort pouch, PET/Aluminum Foil/Nylon/RCPP and PET/Nylon/Modified Aluminum/CPP. The result showed that the different layer arrangement was resulted different Sterilization Value (SV). PET/Nylon/Modified Aluminum/CPP had better heat penetration, implied by the higher value of lethality. PET/Nylon/Modified Aluminum/CPP had the lethality value of 6,24 minutes, whereas the lethality value of PET/Aluminum Foil/Nylon/RCPP was 3,54 minutes.

An influenza A virus (H7N9) anti-neuraminidase monoclonal antibody with prophylactic and therapeutic activity in vivo

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Wilson, Jason R.; Guo, Zhu; Reber, Adrian; Kamal, Ram P.; Music, Nedzad; Gansebom, Shane; Bai, Yaohui; Levine, Min; Carney, Paul; Tzeng, Wen-Pin; Stevens, James; York, Ian A.

2017-01-01

Zoonotic A(H7N9) avian influenza viruses emerged in China in 2013 and continue to be a threat to human public health, having infected over 800 individuals with a mortality rate approaching 40%. Treatment options for people infected with A(H7N9) include the use of neuraminidase (NA) inhibitors. However, like other influenza viruses, A(H7N9) can become resistant to these drugs. The use of monoclonal antibodies is a rapidly developing strategy for controlling influenza virus infection. Here we generated a murine monoclonal antibody (3c10-3) directed against the NA of A(H7N9) and show that prophylactic systemic administration of 3c10-3 fully protected mice from lethal challenge with wild-type A/Anhui/1/2013 (H7N9). Further, post-infection treatment with a single systemic dose of 3c10-3 at either 24, 48 or 72 h post A(H7N9) challenge resulted in both dose- and time-dependent protection of up to 100% of mice, demonstrating therapeutic potential for 3c10-3. Epitope mapping revealed that 3c10-3 binds near the enzyme active site of NA, and functional characterization showed that 3c10-3 inhibits the enzyme activity of NA and restricts the cell-to-cell spread of the virus in cultured cells. Affinity analysis also revealed that 3c10-3 binds equally well to recombinant NA of wild-type A/Anhui/1/2013 and to a variant NA carrying a R289K mutation known to infer NAI resistance. These results suggest that 3c10-3 has the potential to be used as a therapeutic to treat A(H7N9) infections either as an alternative to, or in combination with, current NA antiviral inhibitors. PMID:27713074

Differential outcomes of Zika virus infection in Aedes aegypti orally challenged with infectious blood meals and infectious protein meals.

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Huang, Yan-Jang S; Lyons, Amy C; Hsu, Wei-Wen; Park, So Lee; Higgs, Stephen; Vanlandingham, Dana L

2017-01-01

infection in mosquitoes. Infectious whole blood meals and infectious bovine serum albumin meals containing ZIKV were orally presented to two different groups of Ae. aegypti through membrane feeding. At 7 and 14 days post infection, infectious viruses were detected and viral dissemination from gut to other mosquito tissues was analyzed in orally challenged mosquitoes with 50% tissue culture infectious dose method on Vero76 cells. Zika virus infection was significantly impaired among mosquitoes orally challenged with infectious protein meals as compared to infectious whole blood meals. These results indicate the importance of the blood meal in the infection process of arboviruses in mosquitoes. It provides the basis for future studies to identify critical components in the blood of vertebrate hosts that facilitate arbovirus infection in mosquitoes.

Protective efficacy of Newcastle disease virus expressing soluble trimeric hemagglutinin against highly pathogenic H5N1 influenza in chickens and mice.

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Lisette A H M Cornelissen

Full Text Available BACKGROUND: Highly pathogenic avian influenza virus (HPAIV causes a highly contagious often fatal disease in poultry, resulting in significant economic losses in the poultry industry. HPAIV H5N1 also poses a major public health threat as it can be transmitted directly from infected poultry to humans. One effective way to combat avian influenza with pandemic potential is through the vaccination of poultry. Several live vaccines based on attenuated Newcastle disease virus (NDV that express influenza hemagglutinin (HA have been developed to protect chickens or mammalian species against HPAIV. However, the zoonotic potential of NDV raises safety concerns regarding the use of live NDV recombinants, as the incorporation of a heterologous attachment protein may result in the generation of NDV with altered tropism and/or pathogenicity. METHODOLOGY/PRINCIPAL FINDINGS: In the present study we generated recombinant NDVs expressing either full length, membrane-anchored HA of the H5 subtype (NDV-H5 or a soluble trimeric form thereof (NDV-sH5(3. A single intramuscular immunization with NDV-sH5(3 or NDV-H5 fully protected chickens against disease after a lethal challenge with H5N1 and reduced levels of virus shedding in tracheal and cloacal swabs. NDV-sH5(3 was less protective than NDV-H5 (50% vs 80% protection when administered via the respiratory tract. The NDV-sH5(3 was ineffective in mice, regardless of whether administered oculonasally or intramuscularly. In this species, NDV-H5 induced protective immunity against HPAIV H5N1, but only after oculonasal administration, despite the poor H5-specific serum antibody response it elicited. CONCLUSIONS/SIGNIFICANCE: Although NDV expressing membrane anchored H5 in general provided better protection than its counterpart expressing soluble H5, chickens could be fully protected against a lethal challenge with H5N1 by using the latter NDV vector. This study thus provides proof of concept for the use of recombinant

Needle-free Biojector injection of a dengue virus type 1 DNA vaccine with human immunostimulatory sequences and the GM-CSF gene increases immunogenicity and protection from virus challenge in Aotus monkeys

International Nuclear Information System (INIS)

Raviprakash, Kanakatte; Ewing, Dan; Simmons, Monika; Porter, Kevin R.; Jones, Trevor R.; Hayes, Curtis G.; Stout, Richard; Murphy, Gerald S.

2003-01-01

A dengue-1 DNA vaccine containing sequences encoding premembrane and envelope proteins (DIME) was previously shown to elicit virus neutralizing antibodies in rhesus and Aotus monkeys, and the primates were partially protected from viremia upon challenge. To increase the neutralizing antibody levels and subsequent protection from virus challenge, four strategies were evaluated: (a) coimmunization with a plasmid expressing Aotus GM-CSF gene; (b) coimmunization with a plasmid containing human immunostimulatory sequences (ISS); (c) coimmunization with both the GM-CSF gene and ISS; and (d) delivery of vaccine using the needle-free Biojector system. Vaccination with the mixed formulation containing DIME, GM-CSF gene, and ISS, by either needle injection or Biojector, led to neutralizing antibody titers that were stable for up to 6 months after vaccination. Furthermore, 6 of 7 monkeys (85%), and 7 of 8 monkeys (87%) receiving this formulation were completely protected from viremia when challenged 1 and 6 months after vaccination, respectively. This is a significant improvement compared to our previous study in which one of three monkeys (33%) receiving just the DIME vaccine was completely protected from viremia at 6 months after immunization

Recombinant infectious bronchitis virus (IBV) H120 vaccine strain expressing the hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) protects chickens against IBV and NDV challenge.

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Yang, Xin; Zhou, Yingshun; Li, Jianan; Fu, Li; Ji, Gaosheng; Zeng, Fanya; Zhou, Long; Gao, Wenqian; Wang, Hongning

2016-05-01

Infectious bronchitis (IB) and Newcastle disease (ND) are common viral diseases of chickens, which are caused by infectious bronchitis virus (IBV) and Newcastle disease virus (NDV), respectively. Vaccination with live attenuated strains of IBV-H120 and NDV-LaSota are important for the control of IB and ND. However, conventional live attenuated vaccines are expensive and result in the inability to differentiate between infected and vaccinated chickens. Therefore, there is an urgent need to develop new efficacious vaccines. In this study, using a previously established reverse genetics system, we generated a recombinant IBV virus based on the IBV H120 vaccine strain expressing the haemagglutinin-neuraminidase (HN) protein of NDV. The recombinant virus, R-H120-HN/5a, exhibited growth dynamics, pathogenicity and viral titers that were similar to those of the parental IBV H120, but it had acquired hemagglutination activity from NDV. Vaccination of SPF chickens with the R-H120-HN/5a virus induced a humoral response at a level comparable to that of the LaSota/H120 commercial bivalent vaccine and provided significant protection against challenge with virulent IBV and NDV. In summary, the results of this study indicate that the IBV H120 strain could serve as an effective tool for designing vaccines against IB and other infectious diseases, and the generation of IBV R-H120-HN/5a provides a solid foundation for the development of an effective bivalent vaccine against IBV and NDV.

Reliability of non-lethal assessment methods of body composition and energetic status exemplified by applications to eel (Anguilla anguilla) and carp (Cyprinus carpio)

DEFF Research Database (Denmark)

Klefoth, Thomas; Skov, Christian; Aarestrup, Kim

2013-01-01

tNon-lethal assessments of proximate body composition of fish can help unravelling the physiologicaland condition-dependent mechanisms of individual responses to ecological challenges. Common non-lethal methods designed to index nutrient composition in fish include the relative condition factor (Kn......),bioelectric impedance-based assessments of body composition (BIA), and microwave-based “fat” meters(FM). Previous studies have revealed mixed findings as to the reliability of each of these. We compared theperformance of Kn, BIA and FM at different temperatures to predict energetic status of the whole bodiesof live eel...... approach isthe most suitable method to non-lethally estimate energetic status in both, carp and eel, whereas BIA is oflimited use for energetic measurements in the same species, in contrast to other reports in the literature...

[Bladder tumor lethality. Results in the autonomous community of Rioja between 1975-1991].

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Fernández Fernández, A; Gil Fabra, J; Fernández Ruíz, M; Angulo Castellanos, M G; Blanco Martín, E; Otero Mauricio, G

1998-01-01

Between 1975-1991, a total of 557 cases of bladder carcinoma were identified in the Autonomous Community of La Rioja (CAR) which were followed up to December 1994. The overall lethality was 21.9%. 492 cases with 22.35% lethality were identified in males. In females, however, there was 65 cases with 18.46% lethality. The comparison of males and females lethality resulted in p = 0.525. Lethality between cases diagnosed within each 5-year period analyzed is: 1975-1981: 177 cases, lethality 23.72%. 1982-1986: 168 cases, lethality 30.95%. 1987-1991: 212 cases, lethality 13.20%. Between the first and the second 5-year periods, p = 0.132; between the first and third 5-year periods p = 0.007 and between the second and third 5-year periods p CAR for a 22.35% lethality. Lethality is higher in males that in females but the difference is not statistically significant. In the last 5-year period assessed, 1987-1991, a reduction of lethality from bladder neoplasms has been documented.

The Unstructured Paramyxovirus Nucleocapsid Protein Tail Domain Modulates Viral Pathogenesis through Regulation of Transcriptase Activity.

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Thakkar, Vidhi D; Cox, Robert M; Sawatsky, Bevan; da Fontoura Budaszewski, Renata; Sourimant, Julien; Wabbel, Katrin; Makhsous, Negar; Greninger, Alexander L; von Messling, Veronika; Plemper, Richard K

2018-04-15

The paramyxovirus replication machinery comprises the viral large (L) protein and phosphoprotein (P-protein) in addition to the nucleocapsid (N) protein, which encapsidates the single-stranded RNA genome. Common to paramyxovirus N proteins is a C-terminal tail (Ntail). The mechanistic role and relevance for virus replication of the structurally disordered central Ntail section are unknown. Focusing initially on members of the Morbillivirus genus, a series of measles virus (MeV) and canine distemper virus (CDV) N proteins were generated with internal deletions in the unstructured tail section. N proteins with large tail truncations remained bioactive in mono- and polycistronic minireplicon assays and supported efficient replication of recombinant viruses. Bioactivity of Ntail mutants extended to N proteins derived from highly pathogenic Nipah virus. To probe an effect of Ntail truncations on viral pathogenesis, recombinant CDVs were analyzed in a lethal CDV/ferret model of morbillivirus disease. The recombinant viruses displayed different stages of attenuation ranging from ameliorated clinical symptoms to complete survival of infected animals, depending on the molecular nature of the Ntail truncation. Reinfection of surviving animals with pathogenic CDV revealed robust protection against a lethal challenge. The highly attenuated virus was genetically stable after ex vivo passaging and recovery from infected animals. Mechanistically, gradual viral attenuation coincided with stepwise altered viral transcriptase activity in infected cells. These results identify the central Ntail section as a determinant for viral pathogenesis and establish a novel platform to engineer gradual virus attenuation for next-generation paramyxovirus vaccine design. IMPORTANCE Investigating the role of the paramyxovirus N protein tail domain (Ntail) in virus replication, we demonstrated in this study that the structurally disordered central Ntail region is a determinant for viral

Evasion of interferon responses by Ebola and Marburg viruses.

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Basler, Christopher F; Amarasinghe, Gaya K

2009-09-01

The filoviruses, Ebola virus (EBOV) and Marburg virus (MARV), cause frequently lethal viral hemorrhagic fever. These infections induce potent cytokine production, yet these host responses fail to prevent systemic virus replication. Consistent with this, filoviruses have been found to encode proteins VP35 and VP24 that block host interferon (IFN)-alpha/beta production and inhibit signaling downstream of the IFN-alpha/beta and the IFN-gamma receptors, respectively. VP35, which is a component of the viral nucleocapsid complex and plays an essential role in viral RNA synthesis, acts as a pseudosubstrate for the cellular kinases IKK-epsilon and TBK-1, which phosphorylate and activate interferon regulatory factor 3 (IRF-3) and interferon regulatory factor 7 (IRF-7). VP35 also promotes SUMOylation of IRF-7, repressing IFN gene transcription. In addition, VP35 is a dsRNA-binding protein, and mutations that disrupt dsRNA binding impair VP35 IFN-antagonist activity while leaving its RNA replication functions intact. The phenotypes of recombinant EBOV bearing mutant VP35s unable to inhibit IFN-alpha/beta demonstrate that VP35 IFN-antagonist activity is critical for full virulence of these lethal pathogens. The structure of the VP35 dsRNA-binding domain, which has recently become available, is expected to provide insight into how VP35 IFN-antagonist and dsRNA-binding functions are related. The EBOV VP24 protein inhibits IFN signaling through an interaction with select host cell karyopherin-alpha proteins, preventing the nuclear import of otherwise activated STAT1. It remains to be determined to what extent VP24 may also modulate the nuclear import of other host cell factors and to what extent this may influence the outcome of infection. Notably, the Marburg virus VP24 protein does not detectably block STAT1 nuclear import, and, unlike EBOV, MARV infection inhibits STAT1 and STAT2 phosphorylation. Thus, despite their similarities, there are fundamental differences by which

The Global Virus Network: Challenging chikungunya.

Science.gov (United States)

McSweegan, Edward; Weaver, Scott C; Lecuit, Marc; Frieman, Matthew; Morrison, Thomas E; Hrynkow, Sharon

2015-08-01

The recent spread of chikungunya virus to the Western Hemisphere, together with the ongoing Ebola epidemic in West Africa, have highlighted the importance of international collaboration in the detection and management of disease outbreaks. In response to this need, the Global Virus Network (GVN) was formed in 2011. The GVN is a coalition of leading medical virologists in 34 affiliated laboratories in 24 countries, who collaborate to share their resources and expertise. The GVN supports research, promotes training for young scientists, serves as a technical resource for governments, businesses and international organizations, facilitates international scientific cooperation, and advocates for funding and evidence-based public policies. In response to the spread of chikungunya, the GVN formed a task force to identify research gaps and opportunities, including models of infection and disease, candidate vaccines and antivirals, epidemiology and vector control measures. Its members also serve as authoritative sources of information for the public, press, and policy-makers. This article forms part of a symposium in Antiviral Research on "Chikungunya discovers the New World". Published by Elsevier B.V.

Safety, immunogencity, and efficacy of a cold-adapted A/Ann Arbor/6/60 (H2N2) vaccine in mice and ferrets

International Nuclear Information System (INIS)

Chen, Grace L.; Lamirande, Elaine W.; Jin Hong; Kemble, George; Subbarao, Kanta

2010-01-01

We studied the attenuation, immunogenicity and efficacy of the cold-adapted A/Ann Arbor/6/60 (AA ca) (H2N2) virus in mice and ferrets to evaluate its use in the event of an H2 influenza pandemic. The AA ca virus was restricted in replication in the respiratory tract of mice and ferrets. In mice, 2 doses of vaccine elicited a > 4-fold rise in hemagglutination-inhibition (HAI) titer and resulted in complete inhibition of viral replication following lethal homologous wild-type virus challenge. In ferrets, a single dose of the vaccine elicited a > 4-fold rise in HAI titer and conferred complete protection against homologous wild-type virus challenge in the upper respiratory tract. In both mice and ferrets, the AA ca virus provided significant protection from challenge with heterologous H2 virus challenge in the respiratory tract. The AA ca vaccine is safe, immunogenic, and efficacious against homologous and heterologous challenge in mice and ferrets, supporting the evaluation of this vaccine in clinical trials.

Cure of chronic hepatitis C virus infection in an HIV-coinfected patient with multiple comorbidities and drug interaction challenges.

Science.gov (United States)

Álvarez, Hortensia; Mariño, Ana; Valcarce, Nieves; Khoo, Saye; Bhagani, Sanjay; Schapiro, Jonathan; Llibre, Josep M

2018-01-01

Curing hepatitis C virus (HCV) infection in patients harbouring multiple severe comorbidities is a medical challenge. Evidence-based data are lacking regarding HCV treatment with direct-acting antiviral regimens in particular populations of HCV/HIV-coinfected patients with cirrhosis and chronic kidney disease on haemodialysis. Here, we present the HCV treatment challenges facing a patient with HIV coinfection, prior failure of both HIV-1 and HCV therapy, cirrhosis, end-stage renal failure on haemodialysis, as well as management of drug-drug interactions, especially given the need to receive long-term amiodarone therapy.

Humanitarian Algorithms : A Codified Key Safety Switch Protocol for Lethal Autonomy

OpenAIRE

Nyagudi, Nyagudi Musandu

2014-01-01

With the deployment of lethal autonomous weapons, there is the requirement that any such platform complies with the precepts of International Humanitarian Law. Humanitarian Algorithms[9: p. 9] ensure that lethal autonomous weapon systems perform military/security operations, within the confines of International Humanitarian Law. Unlike other existing techniques of regulating lethal autonomy this scheme advocates for an approach that enables Machine Learning. Lethal autonomous weapons must be ...

Detection of infectious bronchitis virus with the use of real-time quantitative reverse transcriptase-PCR and correlation with virus detection in embryonated eggs.

Science.gov (United States)

Roh, Ha-Jung; Hilt, Deborah A; Jackwood, Mark W

2014-09-01

Real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) assays have been used to detect the presence of challenge virus when the efficacy of infectious bronchitis virus (IBV) vaccine against field viruses is being experimentally evaluated. However, federal guidelines for licensing IBV vaccines indicate that challenge-virus detection following vaccination is to be conducted in embryonated eggs. In this study, we examined qRT-PCR data with the use of universal and type-specific primers and probe sets for IBV detection and compared those data with challenge-virus detection in embryonated eggs to determine if the two methods of evaluating vaccine efficacy are comparable. In addition, we tested the qRT-PCR assays on thermocyclers from two different manufacturers. We found the universal IBV primers and probe set to be comparable to challenge-virus detection in embryonated eggs. However, for some IBV types (Mass41 and Conn on the SmartCycler II and Ark, Mass41, Conn, and GA98 on the ABI 7500) the qRT-PCR assay was more sensitive than virus detection in embryonated eggs. This may simply be due to the universal IBV qRT-PCR assay being more sensitive than virus detection in eggs or to the assay detecting nucleic acid from nonviable virus. This finding is important and needs to be considered when evaluating challenge-virus detection for vaccination and challenge studies, because qRT-PCR could potentially identify positive birds that would otherwise be negative by virus detection in embryonated eggs; thus it could lead to a more stringent measure of vaccine efficacy. We also found that the IBV type-specific primers and probe sets designed in this study were in general less sensitive than the universal IBV primers and probe set. Only the Ark-DPI-spedcific assay on the SmartCycler II and the Ark-DPI-, Mass41-, and DE072/GA98- (for detection of GA98 virus only) specific assays on the ABI 7500 were comparable in sensitivity to virus detection in eggs. We