scholarly journals Protective Efficacy of Recombinant Modified Vaccinia Virus Ankara Delivering Middle East Respiratory Syndrome Coronavirus Spike Glycoprotein

2015 ◽  
Vol 89 (16) ◽  
pp. 8651-8656 ◽  
Author(s):  
Asisa Volz ◽  
Alexandra Kupke ◽  
Fei Song ◽  
Sylvia Jany ◽  
Robert Fux ◽  
...  

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe respiratory disease in humans. We tested a recombinant modified vaccinia virus Ankara (MVA) vaccine expressing full-length MERS-CoV spike (S) glycoprotein by immunizing BALB/c mice with either intramuscular or subcutaneous regimens. In all cases, MVA-MERS-S induced MERS-CoV-specific CD8+T cells and virus-neutralizing antibodies. Vaccinated mice were protected against MERS-CoV challenge infection after transduction with the human dipeptidyl peptidase 4 receptor. This MERS-CoV infection model demonstrates the safety and efficacy of the candidate vaccine.

2019 ◽  
Vol 220 (10) ◽  
pp. 1558-1567 ◽  
Author(s):  
Anwar M Hashem ◽  
Abdullah Algaissi ◽  
Anurodh Shankar Agrawal ◽  
Sawsan S Al-amri ◽  
Rowa Y Alhabbab ◽  
...  

AbstractBackgroundInfection control measures have played a major role in limiting human/camel-to-human transmission of Middle East respiratory syndrome coronavirus (MERS-CoV); however, development of effective and safe human or camel vaccines is warranted.MethodsWe extended and optimized our previous recombinant adenovirus 5 (rAd5)–based vaccine platform characterized by in vivo amplified and CD40-mediated specific responses to generate MERS-CoV S1 subunit-based vaccine. We generated rAd5 constructs expressing CD40-targeted S1 fusion protein (rAd5-S1/F/CD40L), untargeted S1 (rAd5-S1), and Green Fluorescent Protein (rAd5-GFP), and evaluated their efficacy and safety in human dipeptidyl peptidase 4 transgenic (hDPP4 Tg+) mice.ResultsImmunization of hDPP4 Tg+ mice with a single dose of rAd5-S1/F/CD40L elicited as robust and significant specific immunoglobulin G and neutralizing antibodies as those induced with 2 doses of rAd5-S1. After MERS-CoV challenge, both vaccines conferred complete protection against morbidity and mortality, as evidenced by significantly undetectable/reduced pulmonary viral loads compared to the control group. However, rAd5-S1– but not rAd5-S1/F/CD40L–immunized mice exhibited marked pulmonary perivascular hemorrhage post–MERS-CoV challenge despite the observed protection.ConclusionsIncorporation of CD40L into rAd5-based MERS-CoV S1 vaccine targeting molecule and molecular adjuvants not only enhances immunogenicity and efficacy but also prevents inadvertent pulmonary pathology after viral challenge, thereby offering a promising strategy to enhance safety and potency of vaccines.


2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Ayman Mubarak ◽  
Wael Alturaiki ◽  
Maged Gomaa Hemida

Middle East respiratory syndrome coronavirus (MERS-CoV) first emerged in late 2012. Since its emergence, a total of 2279 patients from 27 countries have been infected across the globe according to a World Health Organization (WHO) report (Feb. 12th, 2019). Approximately 806 patients have died. The virus uses its spike proteins as adhesive factors that are proinflammatory for host entry through a specific receptor called dipeptidyl peptidase-4 (DPP4). This receptor is considered a key factor in the signaling and activation of the acquired and innate immune responses in infected patients. Using potent antigens in combination with strong adjuvants may effectively trigger the activation of specific MERS-CoV cellular responses as well as the production of neutralizing antibodies. Unfortunately, to date, there is no effective approved treatment or vaccine for MERS-CoV. Thus, there are urgent needs for the development of novel MERS-CoV therapies as well as vaccines to help minimize the spread of the virus from infected patients, thereby mitigating the risk of any potential pandemics. Our main goals are to highlight and describe the current knowledge of both the innate and adaptive immune responses to MERS-CoV and the current state of MERS-CoV vaccine development. We believe this study will increase our understanding of the mechanisms that enhance the MERS-CoV immune response and subsequently contribute to the control of MERS-CoV infections.


Author(s):  
Sumathi Sivapalasingam ◽  
George A Saviolakis ◽  
Kirsten Kulcsar ◽  
Aya Nakamura ◽  
Thomas Conrad ◽  
...  

Abstract Background REGN3048 and REGN3051 are human monoclonal antibodies (mAb) targeting the spike glycoprotein on the Middle East respiratory syndrome coronavirus (MERS-CoV), which binds to the receptor dipeptidyl peptidase-4 (DPP4) and is necessary for infection of susceptible cells. Methods Preclinical study: REGN3048, REGN3051 and isotype immunoglobulin G (IgG) were administered to humanized DPP4 (huDPP4) mice 1 day prior to and 1 day after infection with MERS-CoV (Jordan strain). Virus titers and lung pathology were assessed. Phase 1 study: healthy adults received the combined mAb (n = 36) or placebo (n = 12) and followed for 121 days. Six dose levels were studied. Strict safety criteria were met prior to dose escalation. Results Preclinical study: REGN3048 plus REGN3051, prophylactically or therapeutically, was substantially more effective for reducing viral titer, lung inflammation, and pathology in huDPP4 mice compared with control antibodies and to each antibody monotherapy. Phase 1 study: REGN3048 plus REGN3051 was well tolerated with no dose-limiting adverse events, deaths, serious adverse events, or infusion reactions. Each mAb displayed pharmacokinetics expected of human IgG1 antibodies; it was not immunogenic. Conclusions REGN3048 and REGN3051 in combination were well tolerated. The clinical and preclinical data support further development for the treatment or prophylaxis of MERS-CoV infection.


Viruses ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1130 ◽  
Author(s):  
Isabell Rall ◽  
Ralf Amann ◽  
Sara Malberg ◽  
Christiane Herden ◽  
Dennis Rubbenstroth

Parrot bornaviruses (PaBVs) are the causative agents of proventricular dilatation disease (PDD), a chronic and often fatal neurologic disorder in Psittaciformes. The disease is widely distributed in private parrot collections and threatens breeding populations of endangered species. Thus, immunoprophylaxis strategies are urgently needed. In previous studies we demonstrated a prime-boost vaccination regime using modified vaccinia virus Ankara (MVA) and Newcastle disease virus (NDV) constructs expressing the nucleoprotein and phosphoprotein of PaBV-4 (MVA/PaBV-4 and NDV/PaBV-4, respectively) to protect cockatiels (Nymphicus hollandicus) against experimental challenge infection. Here we investigated the protective effect provided by repeated immunization with either MVA/PaBV-4, NDV/PaBV-4 or Orf virus constructs (ORFV/PaBV-4) individually. While MVA/PaBV-4-vaccinated cockatiels were completely protected against subsequent PaBV-2 challenge infection and PDD-associated lesions, the course of the challenge infection in NDV/PaBV-4- or ORFV/PaBV-4-vaccinated birds did not differ from the unvaccinated control group. We further investigated the effect of vaccination on persistently PaBV-4-infected cockatiels. Remarkably, subsequent immunization with MVA/PaBV-4 and NDV/PaBV-4 neither induced obvious immunopathogenesis exacerbating the disease nor reduced viral loads in the infected birds. In summary, we demonstrated that vaccination with MVA/PaBV-4 alone is sufficient to efficiently prevent PaBV-2 challenge infection in cockatiels, providing a suitable vaccine candidate against avian bornavirus infection and bornavirus-induced PDD.


2021 ◽  
Vol 12 ◽  
Author(s):  
Minjin Kim ◽  
Yucheol Cheong ◽  
Jinhee Lee ◽  
Jongkwan Lim ◽  
Sanguine Byun ◽  
...  

Influenza virus infections can cause a broad range of symptoms, form mild respiratory problems to severe and fatal complications. While influenza virus poses a global health threat, the frequent antigenic change often significantly compromises the protective efficacy of seasonal vaccines, further increasing the vulnerability to viral infection. Therefore, it is in great need to employ strategies for the development of universal influenza vaccines (UIVs) which can elicit broad protection against diverse influenza viruses. Using a mouse infection model, we examined the breadth of protection of the caspase-triggered live attenuated influenza vaccine (ctLAIV), which was self-attenuated by the host caspase-dependent cleavage of internal viral proteins. A single vaccination in mice induced a broad reactive antibody response against four different influenza viruses, H1 and rH5 (HA group 1) and H3 and rH7 subtypes (HA group 2). Notably, despite the lack of detectable neutralizing antibodies, the vaccination provided heterosubtypic protection against the lethal challenge with the viruses. Sterile protection was confirmed by the complete absence of viral titers in the lungs and nasal turbinates after the challenge. Antibody-dependent cellular cytotoxicity (ADCC) activities of non-neutralizing antibodies contributed to cross-protection. The cross-protection remained robust even after in vivo depletion of T cells or NK cells, reflecting the strength and breadth of the antibody-dependent effector function. The robust mucosal secretion of sIgA reflects an additional level of cross-protection. Our data show that the host-restricted designer vaccine serves an option for developing a UIV, providing pan-influenza A protection against both group 1 and 2 influenza viruses. The present results of potency and breadth of protection from wild type and reassortant viruses addressed in the mouse model by single immunization merits further confirmation and validation, preferably in clinically relevant ferret models with wild type challenges.


2004 ◽  
Vol 11 (2) ◽  
pp. 406-410 ◽  
Author(s):  
Antonio Cosma ◽  
Silja Bühler ◽  
Rashmi Nagaraj ◽  
Caroline Staib ◽  
Anna-Lena Hammarin ◽  
...  

ABSTRACT Vaccination against smallpox is again considered in order to face a possible bioterrorist threat, but the nature and the level of the immune response needed to protect a person from smallpox after vaccination are not totally understood. Therefore, simple, rapid, and accurate assays to evaluate the immune response to vaccinia virus need to be developed. Neutralization assays are usually considered good predictors of vaccine efficacy and more informative with regard to protection than binding assays. Currently, the presence of neutralizing antibodies to vaccinia virus is measured using a plaque reduction neutralization test, but this method is time-consuming and labor-intensive and has a subjective readout. Here, we describe an innovative neutralization assay based on a modified vaccinia virus Ankara (MVA) vector expressing the green fluorescent protein (MVA-gfp). This MVA-gfp neutralization assay is rapid and sensitive and has a high-throughput potential. Thus, it is suitable to monitor the immune response and eventually the efficacy of a large campaign of vaccination against smallpox and to study the vector-specific immune response in clinical trials that use genetically engineered vaccinia viruses. Most importantly, application of the highly attenuated MVA eliminates the safety concern in using the replication-competent vaccinia virus in the standard clinical laboratory.


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