Human microglial transitions at the Aβ–Tau inflection point associate with divergent pathways to dementia and resilience

Alzheimer's disease depends not just on plaques and tangles, but on how brain cells respond to them. Using spatial and single-cell genomics across cognitively impaired octogenarians, healthy octogenarians, and cognitively intact centenarians with similar amyloid levels, we identified six spatial tissue states forming a disease continuum with a critical transition point where amyloid-driven inflammation gives way to tau-linked cellular programs. Microglia drive this shift, progressing from early inflammatory to late antigen-presenting states — and resilient individuals diverged here: healthy octogenarians never activated the late microglial program, while centenarians did so without the expected tau accumulation. This positions microglial state transitions at the amyloid-to-tau boundary as key targets for understanding and promoting resilience to Alzheimer's disease.

• Type: Transcriptome Sequencing
• Archiver: European Genome-phenome Archive (EGA)