A Replicating Single-Cycle Adenovirus Vaccine Against Ebola Virus

J Infect Dis. 2018 Nov 5;218(12):1883-1889. doi: 10.1093/infdis/jiy411.

Abstract

Recent West African Ebola virus (EBOV) epidemics have led to testing different anti-EBOV vaccines, including a replication-defective adenovirus (RD-Ad) vector (ChAd3-EBOV) and an infectious, replication-competent recombinant vesicular stomatitis virus expressing the EBOV glycoprotein (rVSV-EBOV; also known as rVSV-ZEBOV). While RD-Ads elicit protection, when scaled up to human trials, the level of protection may be much lower than that of vaccines containing viruses that can replicate. Although a replication-competent Ad (RC-Ad) vaccine might generate a level of protection approximating that of rVSV, this infectious vector would also risk causing adenovirus disease. We recently described a "single-cycle" adenovirus (SC-Ad) vector that amplifies antigen genes like RC-Ad, but that avoids the risk of adenovirus infection. Here we have tested an SC-Ad6 vector expressing the glycoprotein (GP) from a 2014 EBOV strain in mice, hamsters, and rhesus macaques. We show that SC-Ad6-EBOV GP induces a high level of serum antibodies in all species and mediates significant protection against pseudo-challenge with rVSV-EBOV expressing luciferase in mice and hamsters. These data suggest that SC-Ad6-EBOV GP may be useful during future EBOV outbreaks.

Publication types

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

MeSH terms

  • A549 Cells
  • Adenoviridae
  • Aging
  • Animals
  • Antibodies, Viral / blood*
  • Chlorocebus aethiops
  • Cricetinae
  • Dose-Response Relationship, Immunologic
  • Ebola Vaccines / administration & dosage
  • Ebola Vaccines / immunology*
  • Ebolavirus / immunology*
  • Ebolavirus / physiology
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Glycoproteins / immunology
  • HEK293 Cells
  • Hemorrhagic Fever, Ebola / prevention & control*
  • Humans
  • Immunization Schedule
  • Macaca mulatta
  • Mesocricetus
  • Mice
  • Vaccines, Synthetic / immunology
  • Vero Cells
  • Virus Replication

Substances

  • Antibodies, Viral
  • Ebola Vaccines
  • Glycoproteins
  • Vaccines, Synthetic