CD274 and Alzheimer disease: Mechanistic insights from non-AD neuroinflammatory systems provide complementary evidence: interferon-γ (IFN-γ) robustly induces PD-L1 expression in human astrocytes and microglia, establishing a checkpoint–redox interface that suppresses excessive oxidative injury (Smith et al., 2023; Linnerbauer et al., 2023; Gao et al., 2022).