Consistent with the chronic neuroinflammation observed in AD transgenic mouse models including APP/PS1 mice3,38, 7-month-old APP/PS1 mice exhibited substantial increase in the transcript levels of Il1β and Il6 (major pro-inflammatory factors) and intercellular adhesion molecule 1 (Icam1) (an anti-inflammatory cytokine) in the hippocampus (Fig. 2A–C) and cortex (Supplemental Fig. 2A–C) compared to their WT counterparts. Here, PSEN1 is linked to Alzheimer disease.