Fig. 1

Differentiation of 661W and ARPE-19 cells after STS treatment. a Morphological changes of 661W cells treated with 75 nM STS or vehicle (0.05% DMSO in medium) for 6 h. Scale bar, 10 μm. b Immunostaining of two groups of 661W cells for neuronal marker β-III Tubulin. Scale bar, 20 μm. c Representative neurite tracing images of (b). The average lengths of β-III tubulin-positive neurites were compared between the vehicle and STS-treated group. Data are shown as the means ± SEM, n = 6 samples per group, *p < 0.05. d, e Immunostaining of two-group 661W cells for neuronal markers NeuN, and MAP2, respectively. Scale bar, 20 μm. f–g Representative black-and-white images of (d) and neurite tracing images of (e), respectively. The average fluorescence intensity of NeuN-positive cells and the average lengths of MAP2-positive neurites were quantified. Results are presented as the means ± SEM (n = 6, *p < 0.05). h Western blots (cropped blot images) showing the effect of differentiation with STS on the level of β-III tubulin, NeuN, and MAP2 proteins in 661W cells. β-actin was used as an internal control. The results are shown as the means ± SEM (n = 5, *p < 0.05). i Morphological changes of ARPE-19 cells treated with 75 nM STS or vehicle (0.05% DMSO in medium) for 6 h. Scale bar, 10 μm. j β-III tubulin staining images of two-group ARPE-19 cells. Scale bar, 20 μm. k Representative neurite tracing images of (g) and the quantitative analysis of the average lengths of β-III tubulin-positive neurites. Data are presented as the means ± SEM (n = 6, *p < 0.05)