TGFB1 and Alzheimer disease: Microglia suppress TGFβ signaling as they transition from a homeostatic to the DAM state in 5X-FAD mice (Krasemann et al, 2017), and DAM in human cases of AD have reduced pSMAD3 (Yin et al, 2023), indicating that DAM continue to suppress TGFβ signaling.