Emerging high-throughput proteomic technologies have recently been considered as a powerful means of identifying substrates involved in mood disorders. We performed proteomic profiling using liquid chromatography-tandem mass spectrometry to identify dysregulated proteins in plasma samples of 44, 49, and 50 patients with major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia , respectively, in comparison to 51 healthy controls (HCs).