IL17A and psoriasis: We determined the mRNA expression levels of several inflammatory cytokines that are important in psoriasis (TNF-α, IL-23p19, IL-17A, IL-22, IFN-α, IL-1β, IL-6, and IL-10) and a chemokine that promotes the migration of neutrophils (CXCL2) using quantitative real-time PCR [2,29,30].