A vaccine based on a modified vaccinia virus Ankara vector expressing Zika virus structural proteins controls Zika virus replication in mice

Zika virus (ZIKV) is a re-emerging mosquito-borne flavivirus that affects humans and can cause severe neurological complications, including Guillain-Barré syndrome and microcephaly. Since 2007 there have been three large outbreaks; the last and larger spread in the Americas in 2015. Actually, ZIKV is circulating in the Americas, Southeast Asia, and the Pacific Islands, and represents a potential pandemic threat. Given the rapid ZIKV dissemination and the severe neurological and teratogenic sequelae associated with ZIKV infection, the development of a safe and efficacious vaccine is critical. In this study, we have developed and characterized the immunogenicity and efficacy of a novel ZIKV vaccine based on the highly attenuated poxvirus vector modified vaccinia virus Ankara (MVA) expressing the ZIKV prM and E structural genes (termed MVA-ZIKV). MVA-ZIKV expressed efficiently the ZIKV structural proteins, assembled in virus-like particles (VLPs) and was genetically stable upon nine passages in cell culture. Immunization of mice with MVA-ZIKV elicited antibodies that were able to neutralize ZIKV and induced potent and polyfunctional ZIKV-specific CD8+ T cell responses that were mainly of an effector memory phenotype. Moreover, a single dose of MVA-ZIKV reduced significantly the viremia in susceptible immunocompromised mice challenged with live ZIKV. These findings support the use of MVA-ZIKV as a potential vaccine against ZIKVassembled in virus-like particles (VLPs) and was genetically stable upon nine passages in cell culture. Immunization of mice with MVA-ZIKV elicited antibodies that were able to neutralize ZIKV and induced potent and polyfunctional ZIKV-specific CD8+ T cell responses that were mainly of an effector memory phenotype. Moreover, a single dose of MVA-ZIKV reduced significantly the viremia in susceptible immunocompromised mice challenged with live ZIKV. These findings support the use of MVA-ZIKV as a potential vaccine against ZIK

AG5 is a potent non-steroidal anti-inflammatory and immune regulator that preserves innate immunity

12 pages, 5 figures.-- This is an open access article under the CC BY-NC-ND licenseAn archetypal anti-inflammatory compound against cytokine storm would inhibit it without suppressing the innate immune response. AG5, an anti-inflammatory compound, has been developed as synthetic derivative of andrographolide, which is highly absorbable and presents low toxicity. We found that the mechanism of action of AG5 is through the inhibition of caspase-1. Interestingly, we show with in vitro generated human monocyte derived dendritic cells that AG5 preserves innate immune response. AG5 minimizes inflammatory response in a mouse model of lipopolysaccharide (LPS)-induced lung injury and exhibits in vivo anti-inflammatory efficacy in the SARS-CoV-2-infected mouse model. AG5 opens up a new class of anti-inflammatories, since contrary to NSAIDs, AG5 is able to inhibit the cytokine storm, like dexamethasone, but, unlike corticosteroids, preserves adequately the innate immunity. This is critical at the early stages of any naïve infection, but particularly in SARS-CoV-2 infections. Furthermore, AG5 showed interesting antiviral activity against SARS-CoV-2 in humanized miceThis work has been supported by NextGenerationEU Recovery and Resilience Facility (RRF) through the PTI+ Global Health Platform of Spanish National Research Council, grants SGL2103023 (PBA), SGL2103053 (MMA) and SGL2103015 (MM); by Spanish National Research Council through the program “Ayudas extraodinarias a proyectos de investigacion en el marco de las medidas urgentes extraodinarias para hacer frente al impacto económico y social del COVID-19”, grants CSIC-COV19-093 (PBA) and CSIC-COV19-117 (MM); by Generalitat Valenciana through the program “Ayudas urgentes para proyectos de investigación, desarrollo tecnológico e innovación (I+D+i) por la COVID-19”, grant GVA-COVID19/2021/059 (PBA); by the Conference of Rectors of the Spanish Universities, Spanish National Research Council and Banco Santander through the FONDO SUPERA COVID-19, grant CAPriCORn (JSM, JMB); by Severo Ochoa center of excellence program (grant CEX2021-001230-S) (PBA)Peer reviewe

SuperCam Calibration Targets: Design and Development

SuperCam is a highly integrated remote-sensing instrumental suite for NASA’s Mars 2020 mission. It consists of a co-aligned combination of Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman and Luminescence (TRR/L), Visible and Infrared Spectroscopy (VISIR), together with sound recording (MIC) and high-magnification imaging techniques (RMI). They provide information on the mineralogy, geochemistry and mineral context around the Perseverance Rover. The calibration of this complex suite is a major challenge. Not only does each technique require its own standards or references, their combination also introduces new requirements to obtain optimal scientific output. Elemental composition, molecular vibrational features, fluorescence, morphology and texture provide a full picture of the sample with spectral information that needs to be co-aligned, correlated, and individually calibrated. The resulting hardware includes different kinds of targets, each one covering different needs of the instrument. Standards for imaging calibration, geological samples for mineral identification and chemometric calculations or spectral references to calibrate and evaluate the health of the instrument, are all included in the SuperCam Calibration Target (SCCT). The system also includes a specifically designed assembly in which the samples are mounted. This hardware allows the targets to survive the harsh environmental conditions of the launch, cruise, landing and operation on Mars during the whole mission. Here we summarize the design, development, integration, verification and functional testing of the SCCT. This work includes some key results obtained to verify the scientific outcome of the SuperCam system

Extinction of west nile virus by favipiravir through lethal mutagenesis

Favipiravir is an antiviral agent effective against several RNA viruses. The drug has been shown to protect mice against experimental infection with a lethal dose of West Nile virus (WNV), a mosquito-borne flavivirus responsible for outbreaks of meningitis and encephalitis for which no antiviral therapy has been licensed; however, the mechanism of action of the drug is still not well understood. Here, we describe the potent in vitro antiviral activity of favipiravir against WNV, showing that it decreases virus-specific infectivity and drives the virus to extinction. Two passages of WNV in the presence of 1 mM favipiravir—a concentration that is more than 10-fold lower than its 50% cytotoxic concentration (CC)—resulted in a significant increase in mutation frequency in the mutant spectrum and in a bias toward A¡G and G¡A transitions relative to the population passaged in the absence of the drug. These data, together with the fact that the drug is already licensed in Japan against influenza virus and in a clinical trial against Ebola virus, point to favipiravir as a promising antiviral agent to fight medically relevant flaviviral infections, such as that caused by WNV.Spanish Ministry of Economy and Competitiveness (MINECO) to E.D., and S2013/ABI-2906 (PLATESA) from Comunidad de Madrid/FEDER to J.C.-S. and E.D. Work at Centro de Biología Molecular “Severo Ochoa” was also supported by Fundación R. Areces. CIBERehd is funded by Instituto de Salud Carlos III.Peer Reviewe

Recombinant West Nile virus envelope protein E and domain III expressed in insect larvae protects mice against West Nile disease

In this study, West Nile virus (WNV) envelope (rE) protein and its domain III (rDIII) were efficiently expressed in a cost-effective system based on insect larvae as non-fermentative living biofactories. Mice immunized with the partially purified rE or rDIII elicited high antibodies titers that neutralized viral infectivity in cell culture and in suckling mice. All vaccinated animals were fully protected when challenged with neurovirulent WNV NY99. Passive transfer of protective antibodies from immunized mothers to their offspring occurred both by transplacental and lactation routes. These results indicate that the insect-derived antigens tested may constitute potential vaccine candidates to be further evaluated. © 2010 Elsevier Ltd

Maternal transfer of antibodies to the offspring after mice immunization with insect larvae-derived recombinant hepatitis E virus ORF-2 proteins

Hepatitis E virus (HEV) is a major cause of acute hepatitis in humans, causing outbreaks and epidemics in regions with sub-optimal sanitary conditions, in many of which it is endemic. Nowadays there is no specific therapy or licensed vaccines against HEV infection. In this study, we have analyzed in mice the immunogenicity of HEV open-reading frame 2 (ORF-2) protein, and a truncated form of it lacking the first 111 amino acids, efficiently expressed in an improved baculovirus-based technology using insects as living biofactories. Both recombinant proteins elicited high and long-lasting specific anti HEV antibodies. Passive transfer of immunity from immunized mothers to their offspring was demonstrated to occur both by transplacental and lactation routes. These results indicate that these insect-derived immunogens constitute low-cost potential vaccine candidate to be further evaluated. © 2011 Elsevier B.V

Evaluation of an enzyme-linked immunosorbent assay for detection of West Nile virus infection based on a recombinant envelope protein produced in Trichoplusia ni larvae

West Nile virus (WNV), a Flavivirus distributed most widely, is presenting lately variable epidemiological and ecological patterns, including an increasing virulence that has already caused over 1000 human deaths in USA. Currently, diagnosis of WNV is achieved mainly by enzyme-linked immunoassays (ELISAs) based on the use of inactivated whole WNV (iWNV) as antigen, although results have to be confirmed by plaque reduction neutralization tests (PRNTs). Expression of WNV envelope recombinant E (rE) protein and its usefulness as ELISA antigen are described. Production of rE was achieved upon infection of Trichoplusia ni insect larvae with a recombinant baculovirus. Once optimized, the rE-based ELISA was validated with a battery of mouse and equine sera characterized previously. Concordance with the iWNV-based ELISA used routinely was good (95%), as it was with the reference PRNT (90%), with specificity of 94.4% and sensitivity of 88.1%. Production of rE protein in insect larvae allows for an easy, low cost and quite large-scale yield of partially purified antigen which is suitable for serological diagnosis of WNV, without the need for manipulation of large quantities of infective virus. © 2010 Elsevier B.V

Expression and immunoreactivities of Hepatitis E virus genotype 3 open reading frame-2 (ORF-2) recombinant proteins expressed in insect cells

Hepatitis E virus (HEV) is a fecal-orally transmitted virus that is endemic in many geographical areas with poor sanitary conditions and inadequate water supplies. In Europe, a low-endemic area, an increased number of autochthonous sporadic human cases of patients infected with HEV strains of genotype 3, have been reported lately. The relatively high prevalence of HEV genotype 3 infections in European pigs has raised concerns about a potential zoonotic transmission to humans. Determination of HEV seroprevalence in pigs would help to clarify its incidence and possible zoonotic implications. To this purpose, we have expressed and partially characterized swine genotype 3 HEV open reading frame-2 proteins upon infection of Sf21 insect cells with recombinant baculoviruses. The use of the expressed proteins as diagnostic antigens for the detection of antibodies to HEV has been further assayed with human and swine sera. © Springer Science+Business Media, LLC 2009

TrkA-mediated endocytosis of p75-CTF prevents cholinergic neuron death upon γ-secretase inhibition

20 páginas, 8 figurasγ-secretase inhibitors (GSI) were developed to reduce the generation of Aβ peptide to find new Alzheimer's disease treatments. Clinical trials on Alzheimer's disease patients, however, showed several side effects that worsened the cognitive symptoms of the treated patients. The observed side effects were partially attributed to Notch signaling. However, the effect on other γ-secretase substrates, such as the p75 neurotrophin receptor (p75NTR) has not been studied in detail. p75NTR is highly expressed in the basal forebrain cholinergic neurons (BFCNs) during all life. Here, we show that GSI treatment induces the oligomerization of p75CTF leading to the cell death of BFCNs, and that this event is dependent on TrkA activity. The oligomerization of p75CTF requires an intact cholesterol recognition sequence (CRAC) and the constitutive binding of TRAF6, which activates the JNK and p38 pathways. Remarkably, TrkA rescues from cell death by a mechanism involving the endocytosis of p75CTF. These results suggest that the inhibition of γ-secretase activity in aged patients, where the expression of TrkA in the BFCNs is already reduced, could accelerate cholinergic dysfunction and promote neurodegeneration.This study was supported by the Spanish Minister of Economy and Competitiveness grant SAF2017-84096-R and by the Generalitat Valenciana 2018-55 to M Vilar. I García-Carpio was supported by an Formación de Personal Investigador (FPI) pre-doctoral fellowship (BFU2013/42746-P) and a mobility grant (EEBB-I-15-10278) from the Spanish Minister of Economy and Competitiveness. This work was funded by the Stichting Alzheimer Onderzoek (S16013) and the Fonds voor Wetenschappelijk Onderzoek or Flanders Research Foundation (FWO) research project (G0B2519N) to L Chavez-GutiérrezPeer reviewe

First serological study of hepatitis E virus infection in backyard pigs from Serbia

Hepatitis E virus (HEV) genotype 3 infections in pigs and humans have been lately reported in Europe. In the present study, the prevalence of anti-HEV IgG antibodies in swine was investigated, for the first time, in Serbia by means of an ELISA based on a recombinant open reading frame 2 protein of HEV genotype 3. A total of 315 serum samples from 3 to 4 months-old healthy backyard pigs, collected in 63 herds from 28 towns and villages of 4 different districts of the Vojvodina province, in the northern part of Serbia, were tested. A 34.6% (109/315) of the sera tested were positive. The prevalence of anti-HEV antibodies varied widely between municipalities (range 16.7-75.0%) and herds (range 0-100%). These data indicate that HEV infection is widespread in Serbian backyard pigs. © 2010 Springer Science + Business Media, LLC