IL17A and autism: Therefore, our findings indicate that increased production of Th1 cytokines (IFN-γ) and Th17 cytokines (IL-17), along with no change in Th2 cytokines (IL-4, IL-5, and IL-13), might suggest a skewing toward the Th1/Th17 phenotype and dampening of the Th2 phenotype in the context of autism (Figure 2).