The injection of human embryonic stem cell (ESC)-derived NPCs into immunocompromised APP/PS1-21-NOD-SCID mice [15] or Rag2−/−/AppNL−G−F mice [5] resulted in successful engraftment of neurons exhibiting key AD pathological features in the presence of amyloid plaques, which were not seen after cell injection into NOD-SCID or Rag2−/− control mice devoid of Aβ pathology. Here, APP is linked to Alzheimer disease.