TNF and psoriasis: Circulating blood levels and titer in skin lesions of TH1 cytokines (e.g., IFNγ, IL-2, TNFα) and TH17 cytokines (e.g., IL17A, IL17F, IL22, IL26) are significantly increasedin active psoriasis, as well as eruptive lesion IL23, IL20 and IL15 [11].