A replicating cytomegalovirus-based vaccine encoding a single Ebola virus nucleoprotein CTL epitope confers protection against Ebola virus.

• Published in: PLoS Neglected Tropical Diseases
• Main Authors: Yoshimi Tsuda, Patrizia Caposio, Christopher J Parkins, Sara Botto, Ilhem Messaoudi, Luka Cicin-Sain, Heinz Feldmann, Michael A Jarvis
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2011
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Public aspects of medicine; RA1-1270; Arctic; Human health
• Online Access: https://doi.org/10.1371/journal.pntd.0001275; https://doaj.org/article/223bf6d233f44688a560325d653cd617

Human outbreaks of Ebola virus (EBOV) are a serious human health concern in Central Africa. Great apes (gorillas/chimpanzees) are an important source of EBOV transmission to humans due to increased hunting of wildlife including the 'bush-meat' trade. Cytomegalovirus (CMV) is an highly immunogenic virus that has shown recent utility as a vaccine platform. CMV-based vaccines also have the unique potential to re-infect and disseminate through target populations regardless of prior CMV immunity, which may be ideal for achieving high vaccine coverage in inaccessible populations such as great apes.We hypothesize that a vaccine strategy using CMV-based vectors expressing EBOV antigens may be ideally suited for use in inaccessible wildlife populations. To establish a 'proof-of-concept' for CMV-based vaccines against EBOV, we constructed a mouse CMV (MCMV) vector expressing a CD8+ T cell epitope from the nucleoprotein (NP) of Zaire ebolavirus (ZEBOV) (MCMV/ZEBOV-NP(CTL)). MCMV/ZEBOV-NP(CTL) induced high levels of long-lasting (>8 months) CD8+ T cells against ZEBOV NP in mice. Importantly, all vaccinated animals were protected against lethal ZEBOV challenge. Low levels of anti-ZEBOV antibodies were only sporadically detected in vaccinated animals prior to ZEBOV challenge suggesting a role, at least in part, for T cells in protection.This study demonstrates the ability of a CMV-based vaccine approach to protect against an highly virulent human pathogen, and supports the potential for 'disseminating' CMV-based EBOV vaccines to prevent EBOV transmission in wildlife populations.