PDCD1 and ischemic stroke: However, in other models of neurodegeneration and injury, mixed effects have been described when PD-1 is lacking, ranging from the induction of an “M1”-like phenotype in spinal cord injury in PD-1 KO mice (Yao et al., 2014), to unchanged inflammatory markers in acute and chronic pain models after PD-1 blockade (Chen et al., 2017), to reduced inflammation in ischemic stroke upon anti-PD-L1 antibody treatment (Bodhankar et al., 2015), indicating that the effect of immune checkpoint blockade is diverse depending on the exact disease context and experimental conditions.