MAPT and Alzheimer disease: Furthermore, imaging studies in people across the AD continuum showed that tau propagation follows the spread of activated microglia (Pascoal et al, 2021) and immunophenotyping of the CSF from people with AD revealed an increased number of activated peripheral immune cells (Berriat et al, 2023; Gate et al, 2020) providing further evidence for the interplay between the adaptive and innate immune system in AD (Heneka et al, 2025a).