Efficacy of A Recombinant Subunit Protein-Based Zika Virus Vaccine

Zika Virus (ZIKV), a virus with no severe clinical symptoms or sequelae previously associated with human infection, became a public health threat following an epidemic in French Polynesia in 2013-2014 that resulted in neurological complications associated with infection. Although no treatment currently exists for ZIKV infection, several vaccines using different platforms are in development. Using a recombinant subunit protein platform consisting of antigens produced in Drosophila melanogaster S2 cells, Dr. Axel Lehrer and his colleagues previously demonstrated seroconversion and protection against viremia in an immunocompetent mouse model. In this report, provisionally accepted for publication in Frontiers in Immunology, they demonstrate the efficacy of the recombinant subunit protein ZIKV vaccine in a nonhuman primate (NHP) viremia model. High neutralizing antibody titers were detected in all protected macaques and passive transfer of plasma from these NHPs was sufficient to protect against viremia in mice subsequently infected with ZIKV. Taken together these data demonstrate the immunogenicity and protective efficacy of the recombinant subunit ZIKV vaccine candidate in NHPs as well as highlight the importance of neutralizing antibodies in protection against ZIKV infection and their potential implication as a correlate of protection.