Recent fluid biomarker, neuropathological, and animal research in AD suggests that more severe astrocyte reactivity may contribute to propagating Aβ‐dependent tau phosphorylation at early disease stages11, 12, 13 and that GFAP‐positive astrocytes can internalize tau and may be implicated in its further spread.14, 15. Here, GFAP is linked to Alzheimer disease.