Fig. 1.

CLR01 inhibits lentiviral infection independently of the viral glycoprotein and prevents EBOV plaque formation. (A) Luciferase-encoding lentiviral particles pseudotyped with glycoproteins of viruses of the Filoviridae (EBOV, Marburg virus),Rhabdoviridae (Rabies virus) or the Coronaviridae family (SARS-CoV), were exposed to indicated concentrations of CLR01 or CLR03 and then used to infect Huh-7 cells. After three days, infection rates were determined by quantifying firefly luciferase activity and subtracting background activity derived from uninfected cells. Values represent % reporter gene activities ± SD derived from triplicate infections, normalized to values obtained for cells infected in the absence of tweezers. (B) Analysis of replication competent EBOV was performed using confluent Vero E6 cells in 24-well plates. rgEBOV-eGFP was preincubated with CLR01 or CLR03 and mixtures were added to the cells. After 7 days, samples were analyzed by counting the number of plaques per well and calculating the corresponding plaque forming units per milliliter (PFU/ml) for each inhibitor and dilution. Displayed values represent the mean of three independent experiments ± SD. IC₅₀ values were calculated by GraphPad Prism. One-way ANOVA (non-parametric, grouped), followed by Bonferroni's multiple comparison tests were applied to compare the different CLR01/CLR03 concentrations to cells infected in the absence of compound (* denotes p < 0.01; ** denotes p < 0.001; *** denotes p < 0.0001).