Association between programmed death-1 pathway and major depression

Objectives Major depression (MD) may be associated with inflammation and immunity. PD-1 (programmed death-1), PD-L1 (programmed death-ligand 1) and PD-L2 (programmed death-ligand 2) are among the inhibitory immune mediators on the PD-1 pathway. However, previous data regarding the association between MD and PD-1 pathway were still scarce; therefore, we investigated the association of PD-1 pathway with MD.