Immune dysfunction in autism

Cellular and humoral immune dysfunction, complement deficiencies, abnormal antibody production, and abnormal cytokine levels have been documented in autistic individuals. Complex interactions and links between the immune system, the endocrine system, and the central nervous system have been well established, and have relevance for the pathophysiology of autism. We review the literature of the last 25 years pertaining to the relationship between autism and altered immune response; propose three hypotheses of immunopathogenesis; and review preliminary immunomodulatory treatment strategies. Additional research is needed to determine the role of autoimmune and neuroendocrine factors in autism since most findings are preliminary and the implications of the findings need to be determined to see whether specific therapeutic agents targeting these systems might ameliorate or cure symptoms of autism.