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Characterization of an influenza virus pseudotyped with Ebolavirus glycoprotein
We have produced a new Ebola virus pseudotype: E-S-FLU, which can be handled in biosafety level-1/2 containment for laboratory analysis. E-S-FLU is a single cycle influenza virus coated with Ebolavirus glycoprotein, and it encodes enhanced green fluorescence protein as a reporter that replaces the influenza haemagglutinin. MDCK-SIAT1 cells were transduced to express Ebolavirus glycoprotein as a stable transmembrane protein for E-S-FLU production. Infection of cells by E-S-FLU was dependent on Niemann-Pick C1 protein, which is the well-characterized receptor for Ebola virus entry at the late endosome/lysosome membrane. E-S-FLU was neutralized specifically by anti-Ebola glycoprotein antibody and a variety of small drug molecules that are known to inhibit entry of wild-type Ebola virus. To demonstrate the application of this new Ebola virus pseudotype, we show that a single laboratory batch was sufficient to screen a library (LOPAC®1280 Sigma) of 1280 pharmacologically active compounds for inhibition of virus entry. 215 compounds inhibited E-S-FLU infection, while only 22 inhibited the control H5-S-FLU virus coated in an H5 haemagglutinin. These inhibitory compounds have very dispersed targets and mechanisms of action e.g. calcium channel blockers, estrogen receptor antagonists, anti-histamines, serotonin uptake inhibitors etc. and this correlates with inhibitor screening results with other pseudotypes or wild-type Ebola virus in the literature. E-S-FLU is a new tool for Ebola virus cell entry studies and is easily applied to high throughput screening assays for small molecule inhibitors or antibodies.Importance Ebola virus is from the Filoviridae family and is a biosafety level 4 pathogen. There are no FDA-approved therapeutics for Ebola virus. These characteristics warrant the development of surrogates of Ebola virus that can be handled in more convenient laboratory containment to study the biology of the virus, and screen for inhibitors. Here we characterized a new surrogate named E-S-FLU, that is based on a disabled influenza virus core coated with the Ebola virus surface protein, but does not contain any genetic information from the Ebola virus itself. We show that E-S-FLU uses the same cell entry pathway as wild-type Ebola virus. As an example of the ease of use of E-S-FLU in biosafety level-1/2 containment, we showed that a single production batch could provide enough surrogate virus to screen a standard small molecule library of 1280 candidates for inhibitors of viral entry
Recombinant single-cycle influenza virus with exchangeable pseudotypes allows repeated immunization to augment anti-tumour immunity with immune checkpoint inhibitors
Virus-based tumour vaccines offer many advantages compared to other antigen-delivering systems. They generate concerted innate and adaptive immune response, and robust CD8+ T cell responses. We engineered a non-replicating pseudotyped influenza virus (S-FLU) to deliver the well-known cancer testis antigen, NY-ESO-1 (NY-ESO-1 S-FLU). Intranasal or intramuscular immunization of NY-ESO-1 S-FLU virus in mice elicited a strong NY-ESO-1-specific CD8+ T cell response in lungs and spleen that resulted in the regression of NY-ESO-1-expressing lung tumour and subcutaneous tumour, respectively. Combined administration with anti-PD-1 antibody, NY-ESO-1 S-FLU virus augmented the tumour protection by reducing the tumour metastasis. We propose that the antigen delivery through S-FLU is highly efficient in inducing antigen-specific CD8+ T cell response and protection against tumour development in combination with PD-1 blockade
Comparison of heterosubtypic protection in ferrets and pigs induced by a single-cycle influenza vaccine
Influenza is a major health threat, and a broadly protective influenza vaccine would be a significant advance. Signal Minus FLU
(S-FLU) is a candidate broadly protective influenza vaccine that is limited to a single cycle of replication, which induces a strong
cross-reactive T cell response but a minimal Ab response to hemagglutinin after intranasal or aerosol administration. We tested
whether an H3N2 S-FLU can protect pigs and ferrets from heterosubtypic H1N1 influenza challenge. Aerosol administration of
S-FLU to pigs induced lung tissue-resident memory T cells and reduced lung pathology but not the viral load. In contrast, in
ferrets, S-FLU reduced viral replication and aerosol transmission. Our data show that S-FLU has different protective efficacy in
pigs and ferrets, and that in the absence of Ab, lung T cell immunity can reduce disease severity without reducing challenge viral
replication
Diffuse neutral hydrogen in the HI Parkes All Sky Survey
Observations of neutral hydrogen can provide a wealth of information about
the distribution and kinematics of galaxies. To detect HI beyond the ionisation
edge of galaxy disks, column density sensitivities have to be achieved that
probe the regime of Lyman limit systems. Typically HI observations are limited
to a brightness sensitivity of NHI~10^19 cm-2 but this has to be improved by at
least an order of magnitude. In this paper, reprocessed data is presented that
was originally observed for the HI Parkes All Sky Survey (HIPASS). HIPASS
provides complete coverage of the region that has been observed for the
Westerbork Virgo Filament HI Survey (WVFS), presented in accompanying papers,
and thus is an excellent product for data comparison. The region of interest
extends from 8 to 17 hours in right ascension and from -1 to 10 degrees in
declination. Although the original HIPASS product already has good flux
sensitivity, the sensitivity and noise characteristics can be significantly
improved with a different processing method. The newly processed data has an
1sigma RMS flux sensitivity of ~10 mJy beam-1 over 26 km s-1, corresponding to
a column density sensitivity of ~3\cdot10^17 cm-2. While the RMS sensitivity is
improved by only a modest 20%, the more substantial benefit is in the reduction
of spectral artefacts near bright sources by more than an order of magnitude.
In the reprocessed region we confirm all previously catalogued HIPASS sources
and have identified 29 additional sources of which 14 are completely new HI
detections. Extended emission or companions were sought in the nearby
environment of each discrete detection. With the improved sensitivity after
reprocessing and its large sky coverage, the HIPASS data is a valuable resource
for detection of faint HI emission.(Abridged)Comment: 22 pages plus appendix, 6 figures, appendix will only appear in
online format. Accepted for publication in A&
Age and metallicity gradients in fossil ellipticals
Fossil galaxy groups are speculated to be old and highly evolved systems of
galaxies that formed early in the universe and had enough time to deplete their
galaxies through successive mergers of member galaxies, building up one
massive central elliptical, but retaining the group X-ray halo. Considering
that fossils are the remnants of mergers in ordinary groups, the merger history
of the progenitor group is expected to be imprinted in the fossil central
galaxy (FCG). We present for the first time radial gradients of single-stellar
population (SSP) ages and metallicites in a sample of FCGs to constrain their
formation scenario. Our sample comprises some of the most massive galaxies in
the universe exhibiting an average central velocity dispersion of
km s. Metallicity gradients are throughout negative
with comparatively flat slopes of while
age gradients are found to be insignificant ().
All FCGs lie on the fundamental plane, suggesting that they are virialised
systems. We find that gradient strengths and central metallicities are similar
to those found in cluster ellipticals of similar mass. The comparatively flat
metallicity gradients with respect to those predicted by monolithic collapse
() suggest that fossils are indeed the result of multiple
major mergers. Hence we conclude that fossils are not 'failed groups' that
formed with a top heavy luminosity function. The low scatter of gradient slopes
suggests a similar merging history for all galaxies in our sample.Comment: 14 pages, 12 Figures, accepted for publication in A&
Aerosol Delivery of a Candidate Universal Influenza Vaccine Reduces Viral Load in Pigs Challenged with Pandemic H1N1 Virus
Influenza A viruses are a major health threat to livestock and humans, causing considerable mortality, morbidity, and economic loss. Current inactivated influenza vaccines are strain specific and new vaccines need to be produced at frequent intervals to combat newly arising influenza virus strains, so that a universal vaccine is highly desirable. We show that pandemic H1N1 influenza virus in which the hemagglutinin signal sequence has been suppressed (S-FLU), when administered to pigs by aerosol can induce CD4 and CD8 T cell immune responses in blood, bronchoalveolar lavage (BAL), and tracheobronchial lymph nodes. Neutralizing Ab was not produced. Detection of a BAL response correlated with a reduction in viral titer in nasal swabs and lungs, following challenge with H1N1 pandemic virus. Intratracheal immunization with a higher dose of a heterologous H5N1 S-FLU vaccine induced weaker BAL and stronger tracheobronchial lymph node responses and a lesser reduction in viral titer. We conclude that local cellular immune responses are important for protection against influenza A virus infection, that these can be most efficiently induced by aerosol immunization targeting the lower respiratory tract, and that S-FLU is a promising universal influenza vaccine candidate
Multiphase PMSM and PMaSynRM flux map model with space harmonics and multiple plane cross harmonic saturation
© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Multiphase Synchronous Machines vary in rotor construction and winding distribution leading to non-sinusoidal inductances along the rotor periphery. Moreover, saturation and cross-saturation effects make the precise modeling a complex task. This paper proposes a general model of multi-phase magnet-excited synchronous machines considering multi-dimensional space modeling and revealing cross-harmonic saturation. The models can predict multiphase motor behavior in any transient state, including startup. They are based on flux maps obtained from static 2D Finite-Element (FE) analysis. FE validations have been performed to confirm authenticity of the dynamic models of multiphase PMaSynRMs. Very close to FE precision is guaranteed while computation time is incomparably lower.Postprint (author's final draft
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