IL6 and immune system disorder: In patients with rheumatoid arthritis and depression (Figueiredo-Braga et al., 2018), treatment with IL-6 antagonists significantly attenuated depressive symptoms, although this was probably due to the reduction of the systemic auto-immune disease activity itself, while depressive and anxiety symptoms worsened in hematological patients treated with tocilizumab (Knight et al., 2021).