In autism, as in other neuroinflammatory disorders, changes in zonulin-mediated gut permeability lead to pro-inflammatory status characterized by increased levels of mucosal pro-inflammatory cytokines (IL-5, IL-15, and IL-17) and decreased anti-inflammatory cytokines (transforming growth factor beta 1, or TGFβ1) detected mainly in ASD children experiencing gastrointestinal (GI) symptoms42. Here, TGFB1 is linked to autism.