Fig. 5

RO7019009 retains its modulatory efficiency in iPSC-derived L166P KI neurons. A gRNA binding site in exon 6 of the PSEN1 gene and Sanger sequencing validation of the inserted edits in hetero- and homozygous PS1 L166P KI cells. Both edited lines (hetero- and homozygous) contain a silent mutation in addition to the desired base exchange at the L166 codon. B Representative immunofluorescence stainings of the differentiated neurons at DIV27 (DAPI in blue, MAP2 in pink and tau in green). Single channels are shown in Suppl. Figure 7B; Scalebar: 10 µm. C Aβ profiles of parental and edited neurons after DMSO treatment. The different Aβ species are shown as ratios compared to the sum of measured Aβ (Aβ37 + 38 + 40 + 42 + 43) (n = 14). D Fold change of combined Aβ42 + Aβ43 in the mutant lines compared to parental cells (n = 13). E Ratios of the measured Aβ species after treatment with 500 nM or 2.5 µM RO7019009, or 2.5 µM RO5254601, compared to the DMSO-vehicle treated control. For reasons of visualization, samples that were below detection limit were set to 0 (n = 6–14). F–H Amount of secreted Aβ42 (F), Aβ43 (G) or the combined amount of Aβ42 + Aβ43 (H) in the supernatant of induced neurons that were treated with GSM or DMSO as control (n = 10–14). I Total amount of secreted Aβ of the different neuronal cell lines in the presence of DMSO vehicle or GSM. Total Aβ was measured using pan-Aβ antibodies and is displayed relative to DMSO-treated controls (n = 10–14). The red dashed line (F-I) represents the situation in DMSO-treated WT cells. In (C-E), the Aβ species are displayed as ratio of the sum of measured Aβ (Aβ37 + Aβ38 + Aβ40 + Aβ42 + Aβ43). F-I shows the amount of measured Aβ species as pg/ml. Missing data points are due to Aβ levels below the detection limit of the assay. Statistical significance (F–H) was tested using one-way ANOVA with Dunnett’s multiple comparison test