CD200 and Alzheimer disease: After integrating immune-related gene sets from the InnateDB and ImmPort database, we finally screened 15 IRDEGs (APLNR, TGFBR3, PSDM8, FABP3, CHGB, CXCR4, GFAP, FGF12, UCHL1, COX5B, UBE2N, MAP3K5, SYP, CD200, and GJA1) between the HC and AD groups (Fig. 3F).