Replication-deficient ebolavirus as a vaccine candidate

J Virol. 2009 Apr;83(8):3810-5. doi: 10.1128/JVI.00074-09. Epub 2009 Feb 11.

Abstract

Ebolavirus causes severe hemorrhagic fever, with case fatality rates as high as 90%. Currently, no licensed vaccine is available against Ebolavirus. We previously generated a replication-deficient, biologically contained Ebolavirus, EbolaDeltaVP30, which lacks the essential VP30 gene, grows only in cells stably expressing this gene product, and is genetically stable. Here, we evaluated the vaccine potential of EbolaDeltaVP30. First, we demonstrated its safety in STAT-1-knockout mice, a susceptible animal model for Ebolavirus infection. We then tested its protective efficacy in two animal models, mice and guinea pigs. Mice immunized twice with EbolaDeltaVP30 were protected from a lethal infection of mouse-adapted Ebolavirus. Virus titers in the serum of vaccinated mice were significantly lower than those in nonvaccinated mice. Protection of mice immunized with EbolaDeltaVP30 was associated with a high antibody response to the Ebolavirus glycoprotein and the generation of an Ebolavirus NP-specific CD8(+) T-cell response. Guinea pigs immunized twice with EbolaDeltaVP30 were also protected from a lethal infection of guinea pig-adapted Ebolavirus. Our study demonstrates the potential of the EbolaDeltaVP30 virus as a new vaccine platform.

Publication types

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

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • CD8-Positive T-Lymphocytes / immunology
  • Ebola Vaccines / genetics
  • Ebola Vaccines / immunology*
  • Ebolavirus / genetics
  • Ebolavirus / immunology*
  • Female
  • Gene Deletion*
  • Genes, Essential
  • Guinea Pigs
  • Hemorrhagic Fever, Ebola / immunology
  • Hemorrhagic Fever, Ebola / prevention & control*
  • Immunization, Secondary
  • Mice
  • Mice, Inbred BALB C
  • Mice, Knockout
  • STAT1 Transcription Factor / deficiency
  • Survival Analysis
  • Transcription Factors / genetics*
  • Viral Load
  • Viral Proteins / genetics*
  • Viremia / prevention & control
  • Virus Replication*

Substances

  • Antibodies, Viral
  • Ebola Vaccines
  • STAT1 Transcription Factor
  • Stat1 protein, mouse
  • Transcription Factors
  • VP30 protein, ebola virus
  • Viral Proteins