Two emerging T helper (Th) cell subsets, Th17 and Th22 cells, and their respective prototype cytokines interleukin 17A (IL-17A) and IL-17F and IL-22, link the immune response to tissue inflammation, and play important roles in host defense, autoimmunity, and allergic diseases (Akdis et al., 2012). Here, IL17A is linked to Autoimmunity.