Figure 1. Accumulation of vesicles positive for lysosomal markers in ATP13A2 mutant fibroblasts and primary cortical neurons. A, Left, Representative images of LAMP1 immunostaining of two wild-type fibroblast lines (WT) and fibroblasts carrying ATP13A2 mutation (MUT); Right, quantification of intensity of cell area stained by LAMP1 (n = 80, *p < 0.001). B, Left, Imaging of LysoTracker labeled fibroblasts showed increased number and size of LysoTracker-positive vesicles, arrows indicate enlarged vesicles. Right, graphs: n = 80, *p < 0.001. C, Right, Representative images of LAMP1 immunostaining of primary cortical neurons. Fold change of LAMP1-positive area in ATP13A2 KD neurons compared with scrambled control cells; arrows indicate enlarged vesicles. Left, graph: n = 50, *p < 0.001. D, Right, Primary cortical neurons labeled with LysoTracker Green. Left, graph, quantification of the number of puncta (n = 25, *p < 0.001). E, Left, Mutant or wild-type fibroblasts overexpressing GFP (top) or WT-ATP13A2-GFP (bottom) and immunostained with LAMP1. Right, Quantification of staining intensity is represented as fold change compared with WT line (n = 25). F, Knockdown of ATP13A2 evaluated in cortical neurons by quantitative PCR. GAPDH and 18S were used as control genes (n = 3, *p < 0.001). In all graphs, error bars indicate SEM. Scale bars, 10 μm.