Among the three different approaches tested in our study to induce a “psoriasis-like” inflammatory response in keratinocytes, we selected a method with direct treatment of the HaCaT cells with a mix of proinflammatory cytokines (IL-1A, IL-17A, IL-22), oncostatin M (OSM) and tumor necrosis factor-α (TNF-α) as the most efficient in terms of the expected characteristics. The gene discussed is IL22; the disease is psoriasis.