Subsequently, the secretion of inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), interleukin- (IL) 6, IL-17A and IL-22 elicits psoriasis inflammation that results in keratinocytes upregulation of neutrophil, attracting chemokines such as [(C-X-C motif) ligand-) CXCL1, CXCL2, CXCL3, CXCL5, CXCL8, (C-C motif) ligand-) CCL2, CCL20], antimicrobial peptides (lipocalin-2, β-defensins, S100 calcium-binding proteins) and immunomodulatory molecules such as intercellular adhesion molecule. The gene discussed is IL17A; the disease is psoriasis.