Patients with psoriasis experience higher TEWL, an abnormal proliferation and disrupted differentiation of keratinocytes, with inflammatory lesions, linked with augmented levels of growth factors, chemokines, pro-inflammatory markers, and cytokines like interleukin 17 (IL-17), interleukin 23 (IL-23) and tumor necrosis factor α (TNF-α). Here, IL17A is linked to psoriasis.