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

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.

Objective: We investigated the immune mechanism and therapeutic targets of patients with recalcitrant DRESS with a prolonged disease course.

Methods: A total of 32 patients with recalcitrant DRESS with a prolonged treatment course ≥8 weeks, 28 patients with short-duration DRESS with a treatment course <2 weeks, and 26 healthy individuals were enrolled in the study for analysis.

Results: Bulk transcriptome results demonstrated that mRNA expression levels of CCR8 and CXCR3 were significantly increased in the blood samples from patients in the acute stage of prolonged DRESS (adjusted p-values: CCR8=1.50×10-9 and CXCR3=2.60×10-4, respectively, for comparison of patients with prolonged DRESS to the healthy donor group). Serum and skin lesional concentrations of CCL1 and CXCL10, as the ligands of CCR8 and CXCR3, respectively, were significantly elevated in patients with prolonged DRESS as compared to those patients with short-duration DRESS. The results from high-parameter flow cytometry and autoantibody screening also identified significant escalations of CD8+ GNLY+CXCR3+effector memory T cells, CD8+central memory T cells, CD4+CCR8+Th2 cells, and IgG-anti-HES6 autoantibodies in patients with prolonged DRESS. Furthermore, in vitro blocking assays revealed that JAK inhibitors (mainly tofacitinib and upadacitinib) significantly decreased the release of CCL1 and CXCL10, and some patients with prolonged DRESS were successfully treated with JAK inhibitors.

Conclusions: JAK inhibitors (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 contribute to disease pathogenesis for patients with recalcitrant DRESS and a long-term treatment course.