PDCD1 and Alzheimer disease: As changes in the cognitive function after PD1/PDL1 blockade in both amyloid and tauopathy models have been confirmed (Baruch et al., 2016; Rosenzweig et al., 2019), we will use diverse models such as 3×Tg-AD mice and htau transgenic mice to further verify the PD1-PDL1-GSK3β-tau axis in the future.