IL6 and post-traumatic stress disorder: However, it is noteworthy that contrasting findings were reported by de Oliveira and colleagues (2018) as well as Guo and colleagues (2012), where both proinflammatory cytokines including IL-6 and anti-inflammatory cytokines including IL-4 and IL-10 were positively correlated and elevated in individuals with PTSD as compared to the respective healthy control group [54,72].