Rapid Communication Generation of eGFP expressing recombinant Zaire ebolavirus for analysis of early pathogenesis events and high-throughput antiviral drug screening

AbstractZaire ebolavirus causes large outbreaks of severe and usually fatal hemorrhagic disease in humans for which there is no effectivetreatment or cure. To facilitate examination of early critical events in viral pathogenesis and to identify antiviral compounds, a recombinantZaire ebolavirus was engineered to express a foreign protein, eGFP, to provide a rapid and sensitive means to monitor virus replication ininfected cells. This genetically engineered virus represents the first insertion of a foreign gene into ebolavirus. We show that Ebola-eGFPvirus (EboZ-eGFP) infects known early targets of human infections and serves as an ideal model to screen antiviral compounds in less timethan any previously published assay.Published by Elsevier Inc. Keywords: Zaire ebolavirus; Hemorrhagic disease; eGFP; Recombinant virus IntroductionThe emerging viral pathogens Ebola virus (EboV) andMarburg virus (MbgV) (family Filoviridae) are known tocause devastating disease in human and non-humanprimates. In humans, signs and symptoms of Ebolahemorrhagic fever (EHF) can include gastrointestinal(nausea, abdominal pain), respiratory (shortness of breath,cough) vascular (mucosal hemorrhages, visceral hemorrha-gic effusions, coagulopathy), and central nervous system(headache, dementia, coma) manifestations (Sanchez et al.,2001). The case fatality ranges between 50% and 90% forsome species of EboV with death typically occurringquickly, within 7 to 10 days after onset of symptoms. Dueto the severity of the disease, the rapid onset of symptoms,and the ease of human to human transmission, these virusesare studied exclusively under biosafety level 4 (BSL-4)containment and are listed on the Centers for DiseaseControl and Prevention (CDC) Category A list of potentialbioterrorist agents. Early viral amplification is thought tooccur in mononuclear phagocytes and dendritic cells,followed by massive liver and spleen infection. In somecases there is significant endothelial cell infection andleakage (hemorrhage) in addition to blood coagulationabnormalities such as disseminated intravascular coagula-tion (Geisbert et al., 2003; Sanchez et al., 2001; Zaki andGoldsmith, 1999). Unfortunately, the mechanisms under-lying the severe pathogenesis are only partially understood,highlighting the need to further understand viral replication,especially the early critical events in an infection, as well asdevelop effective antiviral therapies. Currently, there is noeffective antiviral therapy for humans infected with eitherEboV or MbgV, although there have been a number of