Figure 3. High throughput screening.

The HeLa (FXN-EGFP) stable cell line was used in high throughput screening procedures to screen the Spectrum Collection compound library. Each test compound was evaluated at a final concentration of 10 µM. Controls included untreated cells and cells exposed to 3.3 µM cisplatin. Cultures were incubated for 72 hours. The fluorometric measurement of EGFP fluorescence was performed followed by the fluorometric measurement of cell viability. The average background fluorescence of parental HeLa cells was subtracted from the EGFP readings of HeLa (FXN-EGFP) cells exposed to the chemical library. A correction factor for the number of viable cells was applied to the EGFP levels in each corresponding well. This was compared to the average value obtained from cells not exposed to any test compound to determine the level of change in FXN gene expression.