FIGURE 1.

The 384-well forskolin-induced swelling (FIS) assay is reproducible, spatially uniform and has a similar dynamic range to the 96-well FIS-assay. a) Summary of optimisation steps for assay development, specifically for miniaturising a cell-based assay from 96-well format to 384-well format. b) and c) Replicate experiments of three 384-well plates with respectively F508del/S1251N and F508del/F508del patient-derived intestinal organoids (PDIOs), performed on three different culturing days. VX-770 (3 µM) and forskolin (0.008 µM) were added to 128 wells of each 384-well plate to induce minimal swelling (=min signal wells). Maximum swelling was achieved by the addition of 5 µM forskolin and VX-770 (3 µM) to another 128 wells (=max signal wells). The mean±sd swelling of all min and max signal wells of each plate depicted in b and c are summarised in the bar graphs. d) Swelling of F508del/F508del PDIOs treated with VX-770/VX-809 and F508del/S1251N PDIOs treated with VX-770 and in presence of an increasing concentration of forskolin, measured in 96-well plates and 384-well plates (data points represent mean±sd, n=3 for the 96-well experiments, n=1 for the 384-well experiments). e) Z’-factors calculated for each replicate experiment plate included in b, c and d. CV: coefficient of variation; WP: well plate; fsk: forskolin; AUC: area under the curve.