IL6 and post-traumatic stress disorder: Furthermore, posttraumatic stress disorder was found to cause upregulation of serum interleukin 6 (IL-6) and proinflammatory cytokines, such as interferon-gamma (IFN-γ), interleukin 1 β (IL-1β), interleukin 10 (IL 10), and tumor necrosis factor α (TNF α) [75–77].