Increase of ISG15 in Psoriasis Lesions and Its Promotion of Keratinocyte Proliferation via the Wnt Signaling Pathway

Psoriasis is a frequent chronic, recurrent and immune-mediated inflammatory skin disease, whose pathogenesis remains unclear at present. The role of antiviral protein in the pathogenesis of psoriasis is the focus of current research. Interferon stimulated gene 15 (ISG15) is an important antiviral protein. The expression of ISG15 was significantly increased in skin tissues of patients with psoriasis detected by immunofluorescence. In the psoriasis cell model, a remarkable increase also occurred in the expression of ISG15. The rescue experiment verified that ISG15 promotes the proliferation of keratinocytes by regulating the wingless-related integration site (Wnt) signaling pathway. It was concluded that M5-induced Hacat cells and psoriasis skin tissues of patients witnessed the increased expression of ISG15. In psoriasis, knocking out ISG15 inhibits the proliferation of keratinocytes and blocks the cell cycle. Besides, ISG15 promotes the proliferation of keratinocytes through the Wnt signaling pathway.