Upregulation of miR-194 upon hepatocytic differentiation of HepaRG liver progenitor cells. HepaRG cells were induced to differentiate to hepatocyte-like cells as described in Materials and Methods. (A): Pictures were taken at different phases of the culture: progenitor cells (day 2), intermediate (Day 14), and hepatocyte-like cells (day 28). h, hepatocyte-like areas; b, biliary-like areas. Bars, 50 μm. (B): Levels of HNF4A, ALDOB and CYP3A4 mRNAs during hepatocytic differentiation of HepaRG cells measured by quantitative PCR and shown as fold-changes and SEM, at day 14 and day 28 relative to day 2, in two independent experiments. (C): Mean bile canaliculi densities from three randomly selected fields in two independent experiments. (D): Graphs show quantification of secreted human albumin and CYP3A4 activity in HepaRG cells at day 2 and day 28 of the hepatocytic differentiation protocol. (E): Levels of miR-122 and miR-194 during hepatocytic differentiation of HepaRG cells measured by quantitative PCR and shown as fold-changes and SEM, at day 14 and day 28 relative to day 2, in two independent experiments.