CD8A and major depressive disorder: We then validated our hub DEGs using fluorescence-activated cell sorting to separate CD8+ TSCM cells and then performed qPCR to verify that the expression of TBX21, PRF1, and GNLY were significantly increased in CD8+ TSCM cells from MDD patients compared to psychiatrically healthy controls (Supplementary Fig. 4H–J and Supplementary Data 13).