IDO2 and triple-A syndrome: CTLA4, ICOS, TNFRSF25, and NRP had significantly higher expression levels in patients with AAA than in those with AS, whereas TNFSF9, ICOSLG, KIR3DL1, LAIR1, TNFRSF8, IDO2, CD276, CD274, LGALS9, and TMIGD2 were distinctly lower in patients with AAA than in those with AS (Fig. 10B).