The abnormal production of inflammatory cytokines, such as TNF-α, IL-6, IL-17 and IL-23, are confirmed to play key roles in psoriasis [36–38].The protein level of IARS was up-regulated in NHEKs treated with TNF-α, IL-6, IL-17 and IL-23(Fig. 6D). Here, TNF is linked to psoriasis.