EDIII-Fc induces protective immune responses against the Zika virus in mice and rhesus macaque.

Zika virus can infect the fetus through the placental barrier, causing ZIKV congenital syndrome and even miscarriage, which can cause great harm to pregnant women and infants. Currently, there is no vaccine and drug available to combat the Zika virus. In this study, we designed a fusion protein named EDIII-Fc, including the EDIII region of Zika E protein and human IgG Fc fragment, and obtained 293T cells that stably secreted EDIII-Fc protein using the lentiviral expression system. Mice were immunized with the EDIII-Fc protein, and it was observed that viral replication was significantly inhibited in the immunized mice compared to non-immunized mice. In rhesus macaques, we found that EDIII-Fc effectively induce the secretion of neutralizing antibodies and T cell immunity. These experimental data provide valid data for further use of Zika virus E protein to prepare an effective, safe, affordable Zika vaccine.