The phosphatidylinositol-3-phosphate 5-kinase inhibitor apilimod blocks filoviral entry and infection
Confluent dishes of BSC-1 cells were treated with the indicated concentration of apilimod, DMSO (mock), or 10 μM EST for 1 h at 37°C. The cells were then washed, lysed, and the pH adjusted to 5.0 in reaction buffer. Total cathepsin B+L activity was then assayed using the substrate Z-Phe-Arg-7-amido-4-methylcoumarin. Values represent average fluorescence units ± SD of triplicate samples.