IL17A and inflammatory skin disease: Its protein expression level was approximately 3 times higher in psoriatic lesions than in other inflammatory skin disorders.[55] IL-36γ expression correlates with disease activity and decreases during TNF-α treatment, improving disease manifestation.[56] CXCL1 is a member of the CXC subfamily of chemokines, which is up-regulated in the lesional skin of psoriatic patients and down-regulated to normal levels by biologics targeting TNF-α or IL-17A.[57,58] The BPs involved were the response to IFN and granulocyte chemotaxis.