IL4 and bipolar disorder: To provide a more granular view of how particular cytokines relate to brain structure and symptomatology in patients with first-episode schizophrenia and bipolar disorder with psychotic features, we focused on a narrow range of inflammatory markers implicated in previous meta-analyses [14, 15], which included pro-inflammatory cytokines IL-1β, IL-2, IL-6, IL-12, IFN-γ, and TNF-α and the anti-inflammatory cytokines IL-4 and IL-10.