TNF and bipolar disorder: Other studies have also shown that inflammatory markers, especially IL-6 and TNF-α, could vary according to different phases of psychiatric disorder.67, 68 The same was found for inflammatory monocyte gene expression; this was found to be significantly higher in patients with bipolar disorder then in healthy controls during a mood episode, but not in euthymic phase.69 These findings suggest that it is not activation of the immune system, but increased reactivity of the immune system that is associated with psychopathology.