RXR ligands selectively rescue mESC-derived DA neurons from 6-OHDA toxicity. A) 6-OHDA produced a dose dependent toxicity in Lmx1a overexpressing mESC-derived DA cells. Three hours exposure of 150, 250 and 500 μM 6-OHDA reduced the number of DA cells by 33%, 55% and 82%, respectively. B) At 250 μM 6-OHDA, addition of LG268 and XCT completely rescued the DA neurons, from 55% reduction to 100% and 116% of control, respectively. C) Colony of mESC-derived DA cells stained red with Cy3-conjugated anti-TH antibody. 6-OHDA reduced the number of TH-positive cell bodies and remaining cells have degenerate morphology. Simultaneous treatment with LG268 rescued the TH-positive cells from degeneration. Stars (*) refer to differences between control-group (N2B27) and experimental-group, whereas values above brackets refer to differences between different experimental-groups. * denotes p < 0.05, ** denotes p < 0.01 and *** denotes p < 0.001 according to Tukey's multiple comparison test.