JAK inhibitor ruxolitinib inhibits the expression of cytokines characteristic of cutaneous lupus erythematosus.

This study was stimulated by the clinical observation of a rapid response of a chilblain lupus patient to treatment with JAK1/2-kinase inhibitor ruxolitinib. We investigated the in vivo expression of phospho-JAK2 in CLE skin samples as well as the immunomodulatory in vitro effect of ruxolitinib in cultured immortalized keratinocytes and in a 3D human epidermis model (epiCS). Our results demonstrate that ruxolitinib significantly decreases the production of CLE-typical cytokines (CXCL10, CXCL9, MxA) and might be a promising drug for future clinical studies in patients with CLE and related autoimmune skin diseases.