Elevated serum levels of interleukin-17A in children with autism

The T-helper (Th)1/Th2 dichotomy dominated the field of immune regulation until interleukin (IL)-17-expressing T cells (Th17) were proposed to be a third lineage of helper T cells, the key players in the pathogenesis of autoimmune disorders. Autoimmunity to brain tissue may play a pathogenic role in autism. IL-17A is a pro-inflammatory cytokine that has been shown to play an important role in various autoimmune neuroinflammatory diseases. The aim of this study was to measure serum levels of IL-17A in relation to the degree of the severity of autism. Serum IL-17A levels were measured by ELISA in 45 children with autism and 40 matched healthy controls. Children with autism had significantly higher serum IL-17A levels than healthy controls (P