• Vaccine Name: VRP expressing VP40
• Target Pathogen: Ebola virus
• Target Disease: Ebola hemorrhagic fever
• Vaccine Ontology ID: VO_0000784
• Type: Recombinant vector vaccine
• VP40 from Zaire ebolavirus gene engineering:
  • Type: Protein
  • Description:
  • Detailed Gene Information: Click Here.
• Preparation: Replicon RNAs were packaged into particles. Briefly, capped replicon RNAs were produced in vitro by T7 runoff transcription of NotI-digested plasmid templates using the RiboMAX T7 RNA polymerase kit. BHK cells were cotransfected with the replicon RNAs and two RNAs expressing the VEE virus structural proteins. The cell culture supernatants were harvested approximately 30 h after transfection and the replicon particles were concentrated and partially purified by centrifugation through a 20% sucrose cushion. Packaged VRPs were suspended in phosphatebuffered saline and titers were determined as immunofluorescent foci after infection of Vero cells as described using either EBOV-immune rabbit serum or mouse monoclonal antibodies to VP40 (M-HD06-AD10) (Wilson et al., 2001).
• Virulence:
• Description: VP40 is an Ebola virus protein. It is membrane-associated and is most likely located on the inside of the membrane. VP40 has been shown to associate with cell membranes, where it is believed to be involved in maturation of the virus by inducing viral assembly at the plasma membrane of infected cells (Wilson et al., 2001).

Mouse Response

• Host Strain: BALB/c and C57BL/6
• Vaccination Protocol: Groups of 10 BALB/c or C57BL/6 mice per experiment were subcutaneously injected at the base of the neck with 2 x10^6 focus-forming units of VRPs encoding the EBOV-Z genes, or with a control replicon encoding the Lassa N gene. Booster immunizations were administered at 1-month intervals (Wilson et al., 2001).
• Persistence: None noted
• Side Effects: None noted
• Efficacy: Vaccination with VRPs encoding the VP40 protein protected 85 and 70% of the BALB/c mice after either two or three injections, respectively. None of the C57BL/6 mice were protected, however most of the mice had detectable EBOV-Z-specific serum antibodies after vaccination with VRPs encoding the EBOV-Z VP protein (Wilson et al., 2001). These results indicate that the VP30 protein may be an important component of a vaccine designed to protect humans from Ebola hemorrhagic fever.