Fig. 3: Increased Aβ accumulation in iPSC-derived cerebral organoids from AD patients.

Lysates of 4–5 cerebral organoids per iPSC line were analyzed by ELISA and western blotting at week 12. a–c Amounts of Aβ40 (a; APOE4: p = 0.2167, AD: p = 0.0002, APOE4 x AD: p = 0.4849, Con-E3 vs. AD-E3: p = 0.0287, Con-E3 vs. AD-E4: p = 0.0028, Con-E4 vs. AD-E3: p = 0.0171, Con-E4 vs. AD-E4: p = 0.0011) and Aβ42 (b; APOE4: p = 0.1014, AD: p < 0.0001, APOE4 x AD: p = 0.7778, Con-E3 vs. AD-E3: p < 0.0001, Con-E3 vs. AD-E4: p < 0.0001, Con-E4 vs. AD-E3: p < 0.0001, Con-E4 vs. AD-E4: p < 0.0001) in the RIPA fraction were measured by ELISA. Data were normalized to the total protein concentration of the respective sample. The ratio of Aβ42/Aβ40 was calculated accordingly (c; APOE4: p = 0.9549, AD: p = 0.0034, APOE4 x AD: p = 0.5331, Con-E4 vs. AD-E3: p = 0.0397). d–f Amounts of sAPPα (d; APOE4: p = 0.1081, AD: p = 0.8009, APOE4 x AD: p = 0.1351), sAPPβ (E; APOE4: p = 0.7772, AD: p = 0.4410, APOE4 x AD: p = 0.0936) and CTF-β (f; APOE4: p = 0.1150, AD: p = 0.5326, APOE4 x AD: p = 0.9877) in RIPA were measured by ELISA. Data are shown as ratios to Con-E3 after normalization to total protein concentration. g, h Amounts of full-length APP were assessed by western blotting analysis using 22C11 monoclonal antibody in RIPA lysate (APOE4: p = 0.0331, AD: p = 0.6706, APOE4 x AD: p = 0.3170). All data are expressed as mean ± SEM (N = 5). ANCOVA for APOE4, AD status, and APOE4 x AD status was performed by including sex, sampling age, and source of iPSCs as co-variables, which was followed by two-sided Tukey–Kramer tests to compare between the groups with two factors (APOE4 and AD status). *p < 0.05, **p < 0.01, ****p < 0.0001.