IL17A and psoriasis: As for psoriasis, activated myeloid dendritic cells produce IL-12 and IL-23 to promote the development of Th1, Th17, and Th22 cells in psoriasis patients, thus leading to the overproduction of proinflammatory cytokines in psoriatic lesions, including interferon-γ (IFN- γ), IL-1, IL-17, IL-6, IL-12, IL-22, IL-23, and TNF-α (129).