• Vaccine Name: VRP expressing VP30
• Target Pathogen: Ebola virus
• Target Disease: Ebola hemorrhagic fever
• Vaccine Ontology ID: VO_0000782
• Type: Recombinant vector vaccine
• VP30 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 VP24 (Z-AC01-BG11-01), VP35 (M-HC01-AF11), or VP40 (M-HD06-AD10) (Wilson et al., 2001).
• Virulence:
• Description: VP30 is an Ebola virus protein. It associates with the genomic RNA in a ribonucleoprotein complex. The VP30 protein is not essential for replication, but it is necessary for efficient transcription in this system. It has also recently been shown to be essential for the recovery of infectious EBOV-Z from cloned cDNAs (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(10⁶) 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: Three injections of VRPs encoding EBOV-Z VP30 induced protection from lethal disease in 85% of the BALB/c mice examined. However, when the vaccination schedule was decreased to two injections, only 55% of the mice immunized with VP30 survived challenge. None of the C57BL/6 mice were protected. 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 (Wilson et al., 2001).