APOE and Alzheimer disease: No significant differences in GFAP/Tuj1 ratio were observed among the four groups of cerebral organoids by immunostaining (Supplementary Fig. 5A–B), RT-qPCR (Supplementary Fig. 5C), and western blotting (Supplementary Fig. 5D), suggesting that APOE4 or AD status leads to the higher apoE level without increasing astrocyte population in the cerebral organoids.