Vesicular stomatitis virus-based Ebola vaccines with improved cross-protective efficacy

J Infect Dis. 2011 Nov;204 Suppl 3(Suppl 3):S1066-74. doi: 10.1093/infdis/jir348.

Abstract

For Ebola virus (EBOV), 4 different species are known: Zaire, Sudan, Côte d'Ivoire, and Reston ebolavirus. The newly discovered Bundibugyo ebolavirus has been proposed as a 5th species. So far, no cross-neutralization among EBOV species has been described, aggravating progress toward cross-species protective vaccines. With the use of recombinant vesicular stomatitis virus (rVSV)-based vaccines, guinea pigs could be protected against Zaire ebolavirus (ZEBOV) infection only when immunized with a vector expressing the homologous, but not a heterologous, EBOV glycoprotein (GP). However, infection of guinea pigs with nonadapted wild-type strains of the different species resulted in full protection of all animals against subsequent challenge with guinea pig-adapted ZEBOV, showing that cross-species protection is possible. New vectors were generated that contain EBOV viral protein 40 (VP40) or EBOV nucleoprotein (NP) as a second antigen expressed by the same rVSV vector that encodes the heterologous GP. After applying a 2-dose immunization approach, we observed an improved cross-protection rate, with 5 of 6 guinea pigs surviving the lethal ZEBOV challenge if vaccinated with rVSV-expressing SEBOV-GP and -VP40. Our data demonstrate that cross-protection between the EBOV species can be achieved, although EBOV-GP alone cannot induce the required immune response.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Viral / immunology
  • Chlorocebus aethiops
  • Ebola Vaccines / administration & dosage
  • Ebola Vaccines / immunology*
  • Ebolavirus / classification
  • Ebolavirus / immunology*
  • Female
  • Guinea Pigs
  • HEK293 Cells
  • Hemorrhagic Fever, Ebola / prevention & control*
  • Hemorrhagic Fever, Ebola / virology
  • Humans
  • Immunization Schedule
  • Mice
  • Mice, Inbred BALB C
  • Plasmids
  • Vaccines, Attenuated
  • Vaccines, Synthetic
  • Vero Cells
  • Vesiculovirus*

Substances

  • Antigens, Viral
  • Ebola Vaccines
  • Vaccines, Attenuated
  • Vaccines, Synthetic