Figure 1. Response of ACTOne PTGIR cell line to Iloprost. ACTOne PTGIR cells were plated overnight in 20 ml culture medium on a BD Biocoat 384 well plate. The next day, cells were dye-loaded with 20 ml/well of 1X Dye-loading solution (ACTOne Membrane Potential Assay Kit). After 2 hours of incubation at room temperature, two readings were obtained prior to and 30 min after the addition of Iloprost. Ratios of the two readings (F/F0) are plotted in the figure. EC50 = 5.0 pM in the presence of PDE inhibitor Ro20-1724. Parental cells dont respond to Iloprost (Data not shown)