CCR8/CCL1 and CXCR3/CXCL10 axis mediated memory T cell activations in recalcitrant drug-induced hypersensitivity patients

Abstract Background As a drug-induced hypersensitivity syndrome, drug reaction with eosinophilia and systemic symptoms (DRESS) is potentially fatal. Most patients with DRESS recover within a few weeks; however, some patients may suffer from a prolonged disease course and develop autoimmune sequelae. Objectives To investigate the immune mechanism and therapeutic targets of patients with recalcitrant DRESS with a prolonged disease course. Methods Thirty-two patients with recalcitrant DRESS with a prolonged treatment course (≥ 8 weeks; ‘prolonged DRESS’), 28 patients with DRESS with a short treatment course (< 2 weeks; ‘short-duration DRESS’) and 26 healthy donors (HDs) were enrolled. Results Bulk transcriptome results showed that the mRNA expression levels of CCR8 and CXCR3 were significantly increased in blood samples from patients in the acute stage of prolonged DRESS [Padj = 1.50 × 10–9 (CCR8) and Padj = 2.60 × 10–4 (CXCR3), patients with prolonged DRESS compared with the HD group]. Serum and skin lesion concentrations of CCL1 and CXCL10 (ligands of CCR8 and CXCR3, respectively) were significantly increased in patients with prolonged DRESS compared with patients with short-duration DRESS. The results from high-parameter flow cytometry and autoantibody screening also identified significant increases in CD8+ GNLY+ CXCR3+ effector memory T cells, CD8+ central memory T cells, CD4+ CCR8+ T helper 2 cells and IgG anti-HES-6 autoantibodies in patients with prolonged DRESS. Furthermore, in vitro blocking assays revealed that Janus kinase inhibitors (JAKi; mainly tofacitinib and upadacitinib) significantly decreased the release of CCL1 and CXCL10. Some patients with prolonged DRESS were successfully treated with JAKi. Conclusions JAKi (tofacitinib and upadacitinib) were associated with decreased concentrations of CCL1 and CXCL10, suggesting that they may attenuate CCR8/CCL1 and CXCR3/CXCL10 axis-mediated memory T-cell activation, which contributes to disease pathogenesis in patients with recalcitrant DRESS and a long-term treatment course.