We found that osimertinib reduced the percentage of AD-tdTomato+ cells in young adult p53Gfap-icKO mice to p53Gfap-wt/wt control levels, indicating that increased EGFR signaling is necessary for the destabilization of astrocyte identity following p53 loss (Figures 4B and 4C). Here, TP53 is linked to Alzheimer disease.