Fig 3. Effect of deferiprone in transwell-cultured confluent ECC-1 cells: Epithelial monolayer integrity.

Cultures at maximal luminal barrier function (TER ≥ 1000 ohms / cm²) were left untreated, or were treated with deferiprone at the indicated concentrations, every day via the apical chamber and every other day via the basolateral chamber. To document the spontaneous TER fluctuation in the untreated cultures, and any drug-induced deviation from those fluctuations reflective of epithelial monolayer disruption [66], TER measurements of untreated and treated wells were made on consecutive days for a week. P values for untreated vs. treated cultures are shown at 96, 120, and 144 hours after start of deferiprone. In this system, chemicals that cause TER collapse are evident within the first 24 hours of exposure, as shown earlier (e.g. [68]). Def, deferiprone; closed small black squares, 100 μM deferiprone; closed large black squares, 200 μM deferiprone; open cyan circles, untreated controls.