IL-17A acts in synergism with other key-cytokines in psoriasis such as TNF-α and IL-22, stimulating the expression AMPs (LL37, β-defensins, LCN2, S110A family proteins), inflammatory cytokines (IL-1 family members and IL-6), and chemokines (CXL1, -3, -5, -8, and CCL20). The gene discussed is IL17A; the disease is psoriasis.