Th1- and Th2-like cytokines in CD4+ and CD8+ T cells in autism.

Th1-like (IL-2, IFN-gamma) and Th2-like (IL-4, IL-6, and IL-10) cytokines were examined in CD4+ and CD8+ T cells in children with autism. Intracellular cytokines were measured using specific antibodies to various cytokines and anti-CD4 or anti-CD8 monoclonal antibodies by FACScan. Proportions of IFN-gamma+CD4+ T cells and IL-2+CD4+ T cells (Th1), and IFN-gamma+CD8+ and IL-2+CD8+ T cells (TC1) were significantly lower in autistic children as compared to healthy controls. In contrast, IL-4+CD4+ T cells (Th2) and IL-4+CD8+ T cells (TC2) were significantly increased in autism. The proportions of IL-6+ CD4+, IL-6+CD8+ and IL-10+CD4+, IL-10+CD8+ T cells were comparable in autism and control group. These data suggest that an imbalance of Th1- and Th2-like cytokines in autism may play a role in the pathogenesis of autism.