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). The gene discussed is CXCR4; the disease is Alzheimer disease.