Dose response of ribavirin. HEp-2 cells were plated in 384-well black tissue culture plates at 2,000 cells per well. Ribavirin or carrier control (DMSO) were diluted to 6x in Complete DMEM/F12 and serially diluted 1:2 resulting in an 8 point dose response dilution series. (final plate well concentration ranging from 50 uM to 0.39 uM and a final DMSO concentration of 0.5%). For dose response screening, cells were infected with a 1:500 dilution of virus (viral MOI = 0.5). The assay plates were incubated for six days at 37°C, 5% CO2 and 90% relative humidity and the inhibitory effects of the drug were assessed using Cell Titer Glo. The EC50 value (squares) was performed in triplicate while the IC50 value (triangles) was performed in duplicate.