Kunjin Virus Replicon-Based Vaccines Expressing Ebola Virus Glycoprotein GP Protect the Guinea Pig Against Lethal Ebola Virus Infection

Abstract

Pre- or postexposure treatments against the filoviral hemorrhagic fevers are currently not available for human use. We evaluated, in a guinea pig model, the immunogenic potential of Kunjin virus (KUN)-derived replicons as a vaccine candidate against Ebola virus (EBOV). Virus like particles (VLPs) containing KUN replicons expressing EBOV wild-type glycoprotein GP, membrane anchor-truncated GP (GP/Ctr), and mutated GP (D637L) with enhanced shedding capacity were generated and assayed for their protective efficacy. Immunization with KUN VLPs expressing full-length wild-type and D637L-mutated GPs but not membrane anchor-truncated GP induced dose-dependent protection against a challenge of a lethal dose of recombinant guinea pig-adapted EBOV. The surviving animals showed complete clearance of the virus. Our results demonstrate the potential for KUN replicon vectors as vaccine candidates against EBOV infection.