APOE and Alzheimer disease: Neuronal Apoe4 removal diminish disease‐associated subsets of neurons, oligodendrocytes, astrocytes, and microglia.Astrocytic Apoe4 removal diminish disease‐associated subsets of neurons, oligodendrocytes, astrocytes, and microglia.Depletion of microglia has been shown to effectively mitigate Apoe4‐associated pathologies in AD.