A novel Ebola virus expressing luciferase allows for rapid and quantitative testing of antivirals

• A recombinant Ebola virus expressing luciferase (rgEBOV-luc2) was generated.
• Replication of rgEBOV-luc2 can be detected within 2 h after infection.
• A rapid titration assay was developed for rgEBOV-luc2.
• rgEBOV-luc2 can be used for extremely rapid screening of antivirals.

Ebola virus (EBOV) causes a severe hemorrhagic fever with case fatality rates of up to 90%, for which no antiviral therapies are available. Antiviral screening is hampered by the fact that development of cytopathic effect, the easiest means to detect infection with wild-type EBOV, is relatively slow. To overcome this problem we generated a recombinant EBOV carrying a luciferase reporter. Using this virus we show that EBOV entry is rapid, with viral protein expression detectable within 2 h after infection. Further, luminescence-based assays were developed to allow highly sensitive titer determination within 48 h. As a proof-of-concept for its utility in antiviral screening we used this virus to assess neutralizing antibodies and siRNAs, with significantly faster screening times than currently available wild-type or recombinant viruses. The availability of this recombinant virus will allow for more rapid and quantitative evaluation of antivirals against EBOV, as well as the study of details of the EBOV life cycle.