SERPINE1 and Alzheimer disease: 1. AD OM cells had increased amyloid-beta secretion.2. Multiple OM cells had altered signal transduction, RNA, protein metabolism, inflammatory and enriched immune system pathways. 3. From scRNA-seq data, eight genes were differentially expressed between the AD and control groups in entorhinal cortex, viz: HES1, BCYRN1, SERPINE1, MT-ND3, IFI27, MT-ND2, MAP1B, FTH1.