Figure 2(A-B) Confocal images (A) and statistical analysis (B) of cholesterol accumulation in human CTR, MLIV, JNCL, and NPC1 fibroblasts. Cholesterol accumulation was evident for NPC1 and MLIV fibroblasts, but not for JNCL fibroblasts. The images show filipin staining to visualize cholesterol accumulation and TO-PRO3 as nuclear staining. Statistics: Shown are mean values ± SEM. n > 3 technical and biological replicates for each tested condition (each dot represents an imaged frame containing several cells); one-way ANOVA, post hoc Bonferroni's multiple comparisons test (B, *p-value < 0.05; **p-value < 0.01; ***p-value < 0.001; ****p-value < 0.0001.(C-D) TPC2-A1-P (30 µM, 48h) rescued NPC1 and MLIV cholesterol accumulation. Statistics: Shown are mean values ± SEM. n > 3 technical and biological replicates for each tested condition (each dot represents an imaged frame containing several cells); one-way ANOVA, post hoc Bonferroni's multiple comparisons test D, *p-value < 0.05; **p-value < 0.01; ***p-value < 0.001; ****p-value < 0.0001.Confocal images (E-F) of MLIV patient fibroblasts mock-electroporated and treated with DMSO or electroporated with a gain-of-function hTPC2(M484L/G734E):mCherry TOPO 3.1 vector (white arrow heads) and treated with either DMSO or TPC2-A1-P (30 µM, 48h).statistical analysis (G) of MLIV patient fibroblasts mock-electroporated and treated with DMSO or electroporated with a gain-of-function hTPC2(M484L/G734E):mCherry TOPO 3.1 vector (white arrow heads) and treated with either DMSO or TPC2-A1-P (30 µM, 48h). Statistics: Shown are mean values ± SEM. n > 3 technical and biological replicates for each tested condition (each dot represents an imaged frame containing several cells); one-way ANOVA, post hoc Bonferroni's multiple comparisons test *p-value < 0.05; **p-value < 0.01; ***p-value < 0.001; ****p-value < 0.0001.Confocal images and statistical analysis of human CTR patient fibroblasts treated with 50 nM mock siRNA (siSCR) or siRNA targeting TPCN2 (siTPC2) for 72 hours. Cells were then treated with DMSO Statistics: Shown are mean values ± SEM. n > 3 technical and biological replicates for each tested condition (each dot represents an imaged frame containing several cells) two-tailed Student's t-test *p-value < 0.05; **p-value < 0.01; ***p-value < 0.001; ****p-value < 0.0001.Confocal images and statistical analysis of human NPC1 patient fibroblasts treated with 50 nM mock siRNA (siSCR) or siRNA targeting TPCN2 (siTPC2) for 72 hours. Cells were then treated with DMSO or TPC2-A1-P (30 µM). Statistics: Shown are mean values ± SEM. n > 3 technical and biological replicates for each tested condition (each dot represents an imaged frame containing several cells); two-tailed Student's t-test K). *p-value < 0.05; **p-value < 0.01; ***p-value < 0.001; ****p-value < 0.0001.Statistics (L) of human CTR, MLIV, JNCL, and NPC1 fibroblasts. Effect of the treatment with TPC2 agonist (30 µM, 48h) was examined in NPC1 and MLIV cells. Statistics: Shown are mean values ± SEM. n > 3 technical and biological replicates for each tested condition (each dot represents an imaged frame containing several cells); one-way ANOVA, post hoc Bonferroni's multiple comparisons test , L) *p-value < 0.05; **p-value < 0.01; ***p-value < 0.001; ****p-value < 0.0001.electron microscopy images (M) of human CTR, MLIV, JNCL, and NPC1 fibroblasts. Effect of the treatment with TPC2 agonist (30 µM, 48h) was examined in NPC1 and MLIV cells.