Zhao et al. previously reported that the PD-L1/PD-1 pathway modulates hippocampal neuronal excitability and learning and memory behaviors (Zhao et al., 2023), whereas its dysregulation promotes Aβ plaque deposition in AD models (Topalian et al., 2012; Kummer et al., 2021). This evidence concerns the gene CD274 and Alzheimer disease.