AsianScientist (May 11, 2018) – Researchers in China have completed preclinical studies of recombinant protein-based candidate Zika vaccines. Their findings were published in Antiviral Research.
Zika virus (ZIKV) is an RNA virus belonging to the Flavivirus genus of the Flaviviridae family. It is mainly transmitted by mosquitoes. Over the past several years, large ZIKV outbreaks have occurred in the Pacific and the Americas, with millions of people infected.
Clinical studies have revealed associations between ZIKV infection and neurological diseases such as microcephaly and Guillain-Barré syndrome. However, no commercial vaccine is available to prevent ZIKV infection.
In this study, a research group led by Drs. Huang Zhong and Jin Xia at the Institut Pasteur of Shanghai of the Chinese Academy of Sciences produced different forms of ZIKV envelope protein in the Drosophila S2 insect cell expression system. They subsequently evaluated the immunogenicity and protective efficacy of these proteins in mice.
The results showed that the N-terminal region (designated as E80) and the domain III (designated as EDIII) of ZIKV envelope protein could be efficiently produced as secreted proteins in the S2 cell expression system. Both E80 and EDIII elicited antigen-specific neutralizing antibody and T-cell responses in mice.
Importantly, passive transfer of either anti-E80 or anti-EDIII sera protected recipient mice against lethal ZIKV challenge.
At the same dose, EDIII induced higher neutralizing antibody titers than did E80, and the resulting anti-EDIII sera appeared to confer better protection against experimental ZIKV infection compared to the anti-E80 sera.
These data indicated that the S2 cell-produced EDIII represents a potential recombinant Zika vaccine candidate worthy of further preclinical development and clinical testing.
The article can be found at: Qu et al. (2018) Insect Cell-Produced Recombinant Protein Sub-unit Vaccines Protect Against Zika Virus Infection.
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Source: Chinese Academy of Sciences; Photo: Shutterstock.
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