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Background/Aims: Monoclonal antibodies (mAbs) are presently the most promising treatment against Ebola virus disease (EVD), and cocktail of two or more antibodies likely confers protection through complementary mechanisms. Zaire Ebolavirus (EBOV) glycoprotein (GP) and viral protein 40 (VP40) are targets for designing neutralizing antibodies. Currently, the antiviral therapeutics of mAb-cocktails are still limited solely to anti-GP antibodies，there is no Abs cocktail against Zaire EBOV GP and VP40, which both have important interactions with host cellular membrane. Methods: We used hybridoma technology to produce anti-Zaire EBOV GP mAb against GP receptor binding domain, and anti-Zaire EBOV VP40 mAbs against the N-terminal domain, the C-terminal domain, respectively; synthesized Zaire EBOV transcription and replication competent virus like particles (trVLPs), which model even all aspects of the EBOV life cycles in order to evaluate the anti-viral effect of mAbs. Then, we characterized the anti- Zaire EBOV trVLPs effect of anti-GP and VP40 mAbs in vitro by real time-PCR, immunofluorescence assay and western blot analysis. Results: Our results demonstrate that anti-GP or anti-VP40 mAbs effectively inhibit trVLPs replication. The cocktails of anti-GP and anti-VP40 mAbs, or between anti-VP40 mAbs, had synergistic anti-trVLPs effect. Meanwhile, the detailed DNA and amino acid sequences of the mAbs were checked. Conclusion: The study verifies neutralizing efficacy of anti-GP or anti-VP40 mAb, report promising cocktail of anti-GP and anti-VP40 mAb, or cocktail of two anti-VP40 mAbs. To our knowledge, this is the first account to report the important anti-viral effect of cocktails of anti-GP and anti-VP40 mAbs in vitro.

Background/Aims: Since the first case of novel H7N9 infection was reported, China has experienced five epidemics of H7N9. During the fifth wave, a highly pathogenic H7N9 strain emerged. In order to assess whether the H7N9 vaccine based on A/Zhejiang/DTID-ZJU01/2013(H7N9) was effective in protecting against highly pathogenic H7N9, we conducted this study. Methods: Groups of mice were immunized twice by intraperitoneal injection with 500 µl of either split vaccine alone or MF59-adjuvanted vaccine. Serum was collected 2 weeks after the second vaccine booster. The hemagglutinin inhibition test was conducted on vaccine seed and highly pathogenic H7N9 to evaluate the neutralization of highly pathogenic H7N9. We also immunized mice and challenged them with highly pathogenic H7N9. Mice were observed for illness, weight loss, and death at 1 week and 2 weeks post-infection. Then, the mice were sacrificed and lungs were removed. Antibody responses were assessed and pathological changes in the lung tissue were evaluated. Results: The ability of serum to neutralize highly pathogenic H7N9 was reduced. In mice, highly pathogenic H7N9 was more virulent than A/Zhejiang/DTID-ZJU01/2013(H7N9). After challenge with highly pathogenic H7N9, all mice died while mice challenged with A/Zhejiang/DTID-ZJU01/2013(H7N9) all recovered. The A/ZJU01/PR8/2013 split H7N9 avian influenza vaccine was able to protect against infection with highly pathogenic H7N9 in mice, with or without MF59. Moreover, H7N9 vaccine adjuvanted with MF59 produced high antibody levels, which lead to better protection. Conclusions: The A/ZJU01/PR8/2013 split H7N9 avian influenza vaccine based on A/Zhejiang/DTID-ZJU01/2013(H7N9) is effective in protecting against highly pathogenic H7N9. H7N9 vaccine adjuvanted with MF59 offers better protection against infection with highly pathogenic H7N9. In order to make the H7N9 vaccine applicable to humans, further clinical trials are required to evaluate MF59 adjuvanted vaccine. Meanwhile, the vaccine strain should be updated based on the highly pathogenic H7N9 gene sequence.