1. Neurons bearing DSBs enter late-stage DNA damage noticeable by NFkB–activated immune pathways and senescence.2. Suppressed NFkB transcription factor in neurons reduces the spread and activation of microglia in both early and late AD, and rescues synapse loss. 3. NFkB regulates immune gene expression in DSB-bearing neurons, which secrete CCL2 and CXCL10 as primary signaling molecules to recruit and activate microglia. This evidence concerns the gene CCL2 and Alzheimer disease.