APOE4 Causes Widespread Molecular and Cellular Alterations Associated with Alzheimer's Disease Phenotypes in Human iPSC-Derived Brain Cell Types

Neuron. 2018 Jun 27;98(6):1141-1154.e7. doi: 10.1016/j.neuron.2018.05.008. Epub 2018 May 31.


The apolipoprotein E4 (APOE4) variant is the single greatest genetic risk factor for sporadic Alzheimer's disease (sAD). However, the cell-type-specific functions of APOE4 in relation to AD pathology remain understudied. Here, we utilize CRISPR/Cas9 and induced pluripotent stem cells (iPSCs) to examine APOE4 effects on human brain cell types. Transcriptional profiling identified hundreds of differentially expressed genes in each cell type, with the most affected involving synaptic function (neurons), lipid metabolism (astrocytes), and immune response (microglia-like cells). APOE4 neurons exhibited increased synapse number and elevated Aβ42 secretion relative to isogenic APOE3 cells while APOE4 astrocytes displayed impaired Aβ uptake and cholesterol accumulation. Notably, APOE4 microglia-like cells exhibited altered morphologies, which correlated with reduced Aβ phagocytosis. Consistently, converting APOE4 to APOE3 in brain cell types from sAD iPSCs was sufficient to attenuate multiple AD-related pathologies. Our study establishes a reference for human cell-type-specific changes associated with the APOE4 variant. VIDEO ABSTRACT.

Keywords: APOE; Alzheimer’s disease; Aβ; Aβ uptake; CRISPR/Cas9; cerebral organoids; cholesterol; early endosomes; iPSC; immune response.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Video-Audio Media

MeSH terms

  • Alzheimer Disease / genetics*
  • Alzheimer Disease / metabolism
  • Amyloid beta-Peptides / metabolism*
  • Apolipoprotein E3 / metabolism
  • Apolipoprotein E4 / genetics*
  • Apolipoprotein E4 / metabolism
  • Astrocytes / metabolism
  • Brain / cytology
  • Brain / metabolism
  • CRISPR-Cas Systems
  • Cell Differentiation
  • Humans
  • Induced Pluripotent Stem Cells / metabolism*
  • Lipid Metabolism
  • Microglia / immunology
  • Microglia / metabolism
  • Neuroglia / metabolism*
  • Neurons / metabolism*
  • Organoids / metabolism
  • Peptide Fragments / metabolism*
  • Phosphoproteins / metabolism
  • Synaptic Transmission
  • Transcriptome
  • tau Proteins / metabolism*


  • Amyloid beta-Peptides
  • Apolipoprotein E3
  • Apolipoprotein E4
  • MAPT protein, human
  • Peptide Fragments
  • Phosphoproteins
  • amyloid beta-protein (1-42)
  • tau Proteins