We identified IL-17 as the main Th17 cell derived cytokine that induced upregulation of the genes encoding NF-kappa-B inhibitor zeta (NFKBIZ) and psoriasis-associated mediators, including CCL20, IL36G, and the antimicrobial peptide human β Defensin 2 (DEFB4A) (36–41). This evidence concerns the gene IL17A and psoriasis.