ACAT1 and Alzheimer disease: Interestingly, incubation with SMase(s) inhibitors resulted in a significant reduction in both cholesterol esterification by ACAT1, as evidenced by the amount of lipid droplets (LDs), in PS‐DKO cells (Fig 2A), in DAPT‐treated SH‐SY5Y cells (Fig EV3A–C), and in fibroblasts from AD patients (Fig EV3D).