Manette Tanelus
Virginia Polytechnic Institute and State University
Blacksburg, VA
But does it work? Evaluating the safety and immunogenicity of a novel Zika vaccine
Manette Tanelus, Krisangel Lopez, Shaan Smith, John Muller, Dawn Auguste
The flavivirus genus includes many mosquito-borne viruses of medical importance such as Yellow Fever virus, Dengue virus, and Zika virus. Zika virus often induces febrile illness and in severe cases can lead to Guillain Barré Syndrome in the elderly. Zika virus infection during pregnancy is associated with congenital birth defects including microcephaly in newborns. Within this genus, there are insect-specific flaviviruses that cause persistent infections in insects but do not infect or cause disease in humans. Using the close phylogenetic relationship of a mosquito-borne virus (Zika virus) and an insect-specific virus (Aripo virus), we created a chimera (Aripo-Zika) that is unable to replicate in vertebrates but presents the surface proteins of Zika virus. We hypothesize this chimera can serve as a vaccine that will be a safe and efficacious vaccine platform for flaviviruses. Herein, we evaluated the optimal dose and the effects of booster immunizations on immunogenicity in mouse models. Our results indicate a near-linear relationship between increased dose and immunogenicity, with 1011 genome copies being the most effective dose. Higher doses or the inclusion of boosters induce sterilizing immunity. We also explored the efficacy of maternally transferred antibodies in mice. Passive transfer of maternal antibodies to pups resulted in complete protection from a ZIKV challenge. We also confirmed Aripo-Zika remains incapable of replication in vertebrate cells even in the presence of replicating Zika virus via in vitro co-infections in Vero-76 cells. Overall, our data suggest this insect-specific chimeric vaccine platform is a safe and effective platform.
SACNAS National Diversity in STEM Conference, Portland, OR, October 26-28, 2023