ISG15 and Skin ulcer: In order to identify a potential treatment for skin ulcerations due to ISG15 deficiency, we evaluated dexamethasone (DEXA), ruxolitinib (RUX; a JAK1/2 inhibitor that diminishes IFN-I signaling; ref. 32), doxycycline hyclate (DOXY), and TGF-β1.