In addition to contributing to the etiology of depression, activation of proinflammatory signaling pathways occurs as a result of elevated OS.140 Evidence suggests that MDD is associated with the immune response, as shown by increased levels of IL-1β, TNF-α, and IL-6.141 LPS-induced astrocyte activation also contributes to the symptoms of MDD. The gene discussed is IL1B; the disease is major depressive disorder.