Regulation of entheseal IL-23 expression by IL-4 and IL-13 as an explanation for arthropathy development under dupilumab therapy

Objectives Dupilumab blocks the IL-4 receptor (IL-4R) and thus signalling of the ‘Th2’ cytokines IL-4 and IL-13. It has a license to treat atopic eczema and was recently linked to emergent enthesitis and psoriasis. We investigated the cellular and functional basis for how IL-4/IL-13 regulates the IL-23–IL-17 axis in entheseal stromal, myeloid and lymphocyte cells. Methods Immunohistochemistry was performed on healthy enthesis samples from...