IL6 and depressive symptom measurement: Clinical studies have indicated that patients suffering from depression showed significantly higher levels of proinflammatory cytokines, including interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP), and inflammasome, than healthy people [6,20,21,22,23,24].