SOX2 and Alzheimer disease: However, p53Gfap-icKO injured cortices displayed an increase in astrocyte doublets, which is indicative of recent astrocyte proliferation (Figures 2C and 2D) and, more strikingly, uniquely contained a subset of AD-tdTomato+ cells that co-expressed the stemness and transit-amplifying progenitor markers Sox2, Olig2, and Ascl1, indicating that they may have acquired stem-like characteristics (Figures 2C, 2E, 2F, and S2A).