Reverse genetics of Mononegavirales: How they work, new vaccines, and new cancer therapeutics.

The order Mononegavirales includes five families: Bornaviridae, Filoviridae, Nyamaviridae, Paramyxoviridae, and Rhabdoviridae. The genome of these viruses is one molecule of negative-sense single strand RNA coding for five to ten genes in a conserved order. The RNA is not infectious until packaged by the nucleocapsid protein and transcribed by the polymerase and co-factors. Reverse genetics approaches have answered fundamental questions about the biology of Mononegavirales. The lack of icosahedral symmetry and modular organization in the genome of these viruses has facilitated engineering of viruses expressing fluorescent proteins, and these fluorescent proteins have provided important insights about the molecular and cellular basis of tissue tropism and pathogenesis. Studies have assessed the relevance for virulence of different receptors and the interactions with cellular proteins governing the innate immune responses. Research has also analyzed the mechanisms of attenuation. Based on these findings, ongoing clinical trials are exploring new live attenuated vaccines and the use of viruses re-engineered as cancer therapeutics

Rhabdovirus-based vaccine platforms against henipaviruses.

UNLABELLED: The emerging zoonotic pathogens Hendra virus (HeV) and Nipah virus (NiV) are in the genus Henipavirus in the family Paramyxoviridae. HeV and NiV infections can be highly fatal to humans and livestock. The goal of this study was to develop candidate vaccines against henipaviruses utilizing two well-established rhabdoviral vaccine vector platforms, recombinant rabies virus (RABV) and recombinant vesicular stomatitis virus (VSV), expressing either the codon-optimized or the wild-type (wt) HeV glycoprotein (G) gene. The RABV vector expressing the codon-optimized HeV G showed a 2- to 3-fold increase in incorporation compared to the RABV vector expressing wt HeV G. There was no significant difference in HeV G incorporation in the VSV vectors expressing either wt or codon-optimized HeV G. Mice inoculated intranasally with any of these live recombinant viruses showed no signs of disease, including weight loss, indicating that HeV G expression and incorporation did not increase the neurotropism of the vaccine vectors. To test the immunogenicity of the vaccine candidates, we immunized mice intramuscularly with either one dose of the live vaccines or 3 doses of 10 μg chemically inactivated viral particles. Increased codon-optimized HeV G incorporation into RABV virions resulted in higher antibody titers against HeV G compared to inactivated RABV virions expressing wt HeV G. The live VSV vectors induced more HeV G-specific antibodies as well as higher levels of HeV neutralizing antibodies than the RABV vectors. In the case of killed particles, HeV neutralizing serum titers were very similar between the two platforms. These results indicated that killed RABV with codon-optimized HeV G should be the vector of choice as a dual vaccine in areas where rabies is endemic. IMPORTANCE: Scientists have been tracking two new viruses carried by the Pteropid fruit bats: Hendra virus (HeV) and Nipah virus (NiV). Both viruses can be fatal to humans and also pose a serious risk to domestic animals. A recent escalation in the frequency of outbreaks has increased the need for a vaccine that prevents HeV and NiV infections. In this study, we performed an extensive comparison of live and killed particles of two recombinant rhabdoviral vectors, rabies virus and vesicular stomatitis virus (VSV), expressing wild-type or codon-optimized HeV glycoprotein, with the goal of developing a candidate vaccine against HeV. Based on our data from the presented mouse immunogenicity studies, we conclude that a killed RABV vaccine would be highly effective against HeV infections and would make an excellent vaccine candidate in areas where both RABV and henipaviruses pose a threat to human health

Ebola Virus Localization in the Macaque Reproductive Tract during Acute Ebola Virus Disease.

Sexual transmission of Ebola virus (EBOV) has been demonstrated more than a year after recovery from the acute phase of Ebola virus disease (EVD). The mechanisms underlying EBOV persistence and sexual transmission are not currently understood. Using the acute macaque model of EVD, we hypothesized EBOV would infect the reproductive tissues and sought to localize the infection in these tissues using immunohistochemistry and transmission electron microscopy. In four female and eight male macaques that succumbed to EVD between 6 and 9 days after EBOV challenge, we demonstrate widespread EBOV infection of the interstitial tissues and endothelium in the ovary, uterus, testis, seminal vesicle, epididymis, and prostate gland, with minimal associated tissue immune response or organ pathology. Given the widespread involvement of EBOV in the reproductive tracts of both male and female macaques, it is reasonable to surmise that our understanding of the mechanisms underlying sexual transmission of EVD and persistence of EBOV in immune-privileged sites would be facilitated by the development of a nonhuman primate model in which the macaques survived past the acute stage into convalescence

Digitale Direkte Demokratie - Schweizer Volksrechte stärken

Die Digitalisierung löst ein Wechselbad von überzogenen Hoffnungen und irrationalen Ängsten aus. Dies gilt nicht zuletzt für digitale Prozesse in demokratischen Abläufen: Wie wirken sie sich auf die Volksrechte der Schweizerinnen und Schweizer aus? Die neue Avenir-Suisse-Publikation «Digitale Direkte Demokratie» zeigt die Möglichkeiten der elektronischen Mitbestimmung auf, benennt Herausforderungen und zeichnet eine Roadmap für die erfolgreiche Weiterentwicklung direktdemokratischer Instrumente

The cytoplasmic tail of the rabies virus G protein is an essential domain controlling death/survival in human neuronal cells

Poster presentation

Hippocampal EUD in primarily irradiated glioblastoma patients

Background: Radiation delivery for malignant brain tumors is gradually becoming more precise. Particularly the possibilities of sparing adjacent normal structures such as the hippocampus are increasing. To determine its radiation exposure more exactly, the equivalent uniform dose (EUD) of the hippocampus was compared with further treatment parameters. This way sparing options could be found. Methods: From the database of the University hospital of Munich 61 glioblastoma patients were selected who received primary radiotherapy in 2011. General data about the etiology, treatment course, survival of the patients and dose parameters were retrieved. Results: In a linear regression analysis the side of the tumor (left hippocampus: p < 0.001/right hippocampus: p = 0.009) and its temporal location (left hippocampus: p = 0.015/right hippocampus: p = 0.033) were identified as factors with a significant influence on the EUD of the respective hippocampus. Besides this, the size of the planning target volume (PTV) and the EUD of the hippocampus correlated significantly (p = 0.027;Pearson correlation = 0.291). The median PTV size of the tumor in the right hemisphere was 386.1 ml (range 131.2-910.7 ml), and in the left hemisphere 291.3 ml (range 146.0-588.9 ml) (Kruskal-Wallis test: p = 0.048). A dose quartile analysis showed that 31 patients had a high dose exposure of the hippocampus on one side while having a moderate dose exposure in the other side. Conclusions: The radiation exposure of the respective hippocampus is dependent on the side where the tumor is located as well as on whether it is temporally located. The exposure of the contralateral hippocampus is further dependent on multiple additional factors - nevertheless a reasonable protection seems to be possible in about half of all cases

Effects of Adjuvants in a Rabies-Vectored Ebola Virus Vaccine on Protection From Surrogate Challenge

Ebola virus is the primary contributor to the global threat of filovirus severe hemorrhagic fever, and Ebola virus disease has a case fatality rate of 50-90%. An inactivated, bivalent filovirus/rabies virus vaccine, FILORAB1, consists of recombinant rabies virus virions expressing the Ebola virus glycoprotein. FILORAB1 is immunogenic and protective from Ebola virus challenge in mice and non-human primates, and protection is enhanced when formulated with toll-like receptor 4 agonist Glucopyranosyl lipid adjuvant (GLA) in a squalene oil-in-water emulsion (SE). Through an adjuvant comparison in mice, we demonstrate that GLA-SE improves FILORAB1 efficacy by activating the innate immune system and shaping a Th1-biased adaptive immune response. GLA-SE adjuvanted mice and those adjuvanted with the SE component are better protected from surrogate challenge, while Th2 alum adjuvanted mice are not. Additionally, the immune response to FILORAB1 is long-lasting, as exhibited by highly-maintained serum antibody titers and long-lived cells in the spleen and bone marrow

A replication-deficient rabies virus vaccine expressing Ebola virus glycoprotein is highly attenuated for neurovirulence

AbstractWe are developing inactivated and live-attenuated rabies virus (RABV) vaccines expressing Ebola virus (EBOV) glycoprotein for use in humans and endangered wildlife, respectively. Here, we further characterize the pathogenesis of the live-attenuated RABV/EBOV vaccine candidates in mice in an effort to define their growth properties and potential for safety. RABV vaccines expressing GP (RV-GP) or a replication-deficient derivative with a deletion of the RABV G gene (RVΔG-GP) are both avirulent after intracerebral inoculation of adult mice. Furthermore, RVΔG-GP is completely avirulent upon intracerebral inoculation of suckling mice unlike parental RABV vaccine or RV-GP. Analysis of RVΔG-GP in the brain by quantitative PCR, determination of virus titer, and immunohistochemistry indicated greatly restricted virus replication. In summary, our findings indicate that RV-GP retains the attenuation phenotype of the live-attenuated RABV vaccine, and RVΔG-GP would appear to be an even safer alternative for use in wildlife or consideration for human use

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

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