Figure 2. Stat1 activation not involved in IFNγ-induced VEGF secretion. A: ARPE-19 cells were transfected with SiRNA oligos targeting Stat1. After 3 days, cells were cultured with or without IFNγ for 30 min. Cells were then collected and processed for western blot analysis for p-Stat1 expression. The same blot was also stained with anti-β-actin antibody for loading control purposes. B: ARPE-19 cells were mock-transfected or transfected with SiRNA of Stat1. Two days later, cells were treated with or without IFNγ for 48 h. Cell supernatants were collected and used for ELISA analysis. The y-axis represents VEGF concentration (pg/ml). The values are expressed as the average+SEM of triplicates for each treatment. The double asterisk indicates statistical significance (p<0.01) compared to the IFNγ group.