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Sauerhering, L.

Publications and source records attributed to Sauerhering, L..

3 recordsLinked to original sources

Lethal Sudan virus infection in IFNAR-/- mice reveals hallmarks of a cytokine storm

Sudan virus (SUDV) is a member of the family Filoviridae, which comprises highly pathogenic viruses associated with unusually high case fatality rates. The development of medical countermeasures against filoviruses, including antivirals, vaccines, and therapeutic antibodies, requires preclinical evaluation in suitable animal models. C57BL/6J IFNAR-/- mice, which lack the type I interferon (IFN-/{beta}) receptor, have been reported to be susceptible to filovirus infections, although their impaired innate immune response may represent a potential limitation of the model. Here, we show that IFNAR-/- mice constitute a suitable model for SUDV infection. Following infection, animals developed a clear clinical disease characterized by significant weight loss and pronounced changes in behaviour and appearance. Mice reached the predefined clinical endpoint 3-5 days post infection. Post mortem analysis of terminal samples revealed high viral loads and viral genome copies in all tested organs as well as in serum, indicating widespread systemic dissemination. Importantly, infection was associated with a marked increase in several key chemokines and cytokines linked to systemic inflammation, consistent with the development of a cytokine storm-like response. Together, these findings demonstrate that SUDV infection in IFNAR-/- mice induces systemic viral dissemination and a pronounced inflammatory response, supporting the suitability of this model for investigating filovirus pathogenesis and infection-associated immune dysregulation.

microbiology↗

Intranasal administration of a monoclonal neutralizing antibody protects mice against SARS-CoV-2 infection

Despite recent availability of vaccines against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), there is an urgent need for specific anti-SARS-CoV-2 drugs. Monoclonal neutralizing antibodies are an important drug class in the global fight against the SARS-CoV-2 pandemic due to their ability to convey immediate protection and their potential to be used as both, prophylactic and therapeutic drugs. Clinically used neutralizing antibodies against respiratory viruses are currently injected intravenously, which can lead to suboptimal pulmonary bioavailability and thus to a lower effectiveness. Here we describe DZIF-10c, a fully human monoclonal neutralizing antibody that binds the receptor-binding domain of SARS-CoV-2 spike protein. DZIF-10c displays an exceptionally high neutralizing potency against SARS-CoV-2 and retains activity against the variants of concern B.1.1.7 and B.1.351. Importantly, not only systemic but also intranasal application of DZIF-10c abolished presence of infectious particles in the lungs of SARS-CoV-2 infected mice and mitigated lung pathology. Along with a favorable pharmacokinetic profile, these results highlight DZIF-10c as a novel human SARS-CoV-2 neutralizing antibody with high in vitro and in vivo antiviral potency. The successful intranasal application of DZIF-10c paves the way for clinical trials investigating topical delivery of anti-SARS-CoV-2 antibodies. Significance StatementMonoclonal neutralizing antibodies are important in the global fight against the SARS-CoV-2 pandemic due to their ability to convey immediate protection. However, their intravenous application might lead to suboptimal bioavailability in the lung. We here precisely characterize a new monoclonal neutralizing antibody (DZIF-10c) that binds to the receptor binding domain of the spike protein of SARS-CoV-2. DZIF-10c neutralizes SARS-CoV-2 with exceptionally high potency and maintains activity against circulating variants of concern. The antibody has a favorable pharmacokinetic profile and protects mice from SARS-CoV-2 infection. Importantly, we show that intranasal administration of DZIF-10c generates protective efficacy. These results not only identify DZIF-10c as a novel highly potent neutralizing antibody, but further pave the way for a topical application of anti-SARS-CoV-2 antibodies.

microbiology↗

Immunogenicity and efficacy of the COVID-19 candidate vector vaccine MVA SARS 2 S in preclinical vaccination

The severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) has emerged as the infectious agent causing the pandemic coronavirus disease 2019 (COVID-19) with dramatic consequences for global human health and economics. Previously, we reached clinical evaluation with our vector vaccine based on vaccinia virus MVA against the Middle East respiratory syndrome coronavirus (MERS-CoV), which causes an infection in humans similar to SARS and COVID-19. Here, we describe the construction and preclinical characterization of a recombinant MVA expressing full-length SARS-CoV-2 spike (S) protein (MVA-SARS-2-S). Genetic stability and growth characteristics of MVA-SARS-2-S, plus its robust synthesis of S antigen, make it a suitable candidate vaccine for industrial scale production. Vaccinated mice produced S antigen-specific CD8+ T cells and serum antibodies binding to S glycoprotein that neutralized SARS-CoV-2. Prime-boost vaccination with MVA-SARS-2-S protected mice sensitized with a human ACE2-expressing adenovirus from SARS-CoV-2 infection. MVA-SARS-2-S is currently being investigated in a phase I clinical trial as aspirant for developing a safe and efficacious vaccine against COVID-19. Significance StatementThe highly attenuated vaccinia virus MVA is licensed as smallpox vaccine, and as vector it is a component of the approved Adenovirus-MVA-based prime-boost vaccine against Ebola virus disease. Here we provide results from testing the COVID-19 candidate vaccine MVA-SARS-2-S, a poxvirus-based vector vaccine that proceeded to clinical evaluation. When administered by intramuscular inoculation, MVA-SARS-2-S expresses and safely delivers the full-length SARS-CoV-2 spike (S) protein, inducing balanced SARS-CoV-2-specific cellular and humoral immunity, and protective efficacy in vaccinated mice. Substantial clinical experience has already been gained with MVA vectors using homologous and heterologous prime-boost applications, including the immunization of children and immunocompromised individuals. Thus, MVA-SARS-2-S represents an important resource for developing further optimized COVID-19 vaccines.

microbiology↗