T細胞於難治型伴隨嗜伊紅性白血球增加與全身症狀的藥物反應角色之研究

研究目的：伴隨嗜伊紅性白血球增加與全身症狀的藥物反應（DRESS）是一種危及生命的嚴重皮膚不良反應。多數DRESS病人在治療2週內皮疹能夠快速消退；而有些DRESS病人可能會經歷病程延長，治療效果差，甚至出現自體免疫後遺症，稱為難治型DRESS。本研究旨在探討這些難治型DRESS病人漫長病程的免疫機制與T細胞的角色，並尋找可能的治療方式。研究方法及資料：從台灣多個醫療中心納入32名治療期大於8週的難治型DRESS病人和28名治療期小於2週的快速治療反應的DRESS病人以及6名不伴隨系統性症狀的斑丘疹性藥物疹和26名健康個體進行分析。運用RNA轉錄組定序，細胞激素、趨化因子和發炎相關蛋白質的血清濃度評估，高參數流式細胞儀分析周邊血單核細胞，人類皰疹病毒6、7型檢測，病人皮膚病灶與健康對照組皮膚組織的免疫螢光染色，免疫球蛋白G自體抗體檢測，實驗室細胞阻斷試驗進行各種分析，並對部分難治型DRESS病人以Janus激?抑制劑治療並檢測治療前後趨化因子之變化。研究結果：轉錄分析結果顯示，在難治型DRESS病人急性階段的血液樣本中，CC基序趨化因子受體8（CCR8）和CXC基序趨化因子受體3（CXCR3）的mRNA表達量顯著增加（校正後P值分別為：CCR8=1.50×10^-9 和 CXCR3=2.60×10^-4；與健康個體組相比）。在發病後第8週時，CCR8的配體CCL1和CXCR3的配體CXCL10，的血清中含量在難治型DRESS病人中也顯著高於快速療效反應DRESS病人。高參數細胞分析結果顯示CD8+中央記憶T細胞性、CD8+CD69+GNLY+效應記憶性T細胞，以及CD4+Th2+CCR8+細胞的比例，在難治型DRESS病人中與快速治療反應DRESS病人相比顯著提高（所有P均 <0.05）。難治型DRESS病人組有發現臨床意義仍未明的IgG -抗-HES6自體抗體。體外T細胞阻斷試驗與後續Janus激?抑制劑治療顯示，新型Janus激?抑制劑能顯著減少難治型DRESS病人的CCL1和CXCL10分泌。結論與建議：CCR8/CCL1和CXCR3/CXCL10軸與難治型DRESS的致病機轉有關，可能是經由促進記憶性T細胞的招募，而導致難治型DRESS，也可能與病人長期自體免疫後遺症有關。JAK抑制劑可以是這類病人的治療選項。

Objective： Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is a life-threatening severe cutaneous adverse reaction. Though most DRESS patients respond well to treatment within two weeks, some may have autoimmune sequelae and need longer. This research aims to understand the immune system and roles of T cells of recalcitrant DRESS patients with extended courses and discover treatment targets. Methods and Materials： The study in Taiwan included 32 recalcitrant DRESS patients (treatment ?8 weeks), 28 rapid-respond DRESS (treatment <2 weeks), 6 maculopapular exanthema (MPE) patients without systemic symptoms, and 26 healthy individuals from various medical institutes. RNA transcriptome sequencing, serum cytokines, chemokines, and inflammation-related protein concentrations, high-parameter flow cytometry analysis of peripheral blood mononuclear cells, HHV6/7 detection, immunofluorescence staining of patient skin lesions and healthy control skin tissues, IgG autoantibodies measurement, and laboratory cell blocking assays were performed. Janus kinase (JAK) inhibitors were also given to recalcitrant DRESS patients, and chemokines were evaluated.Results： Recalcitrant DRESS patients had significantly higher mRNA expression levels of CC motif chemokine receptor 8 (CCR8) and CXC motif chemokine receptor 3 (CXCR3) in their blood samples (Adjusted P values: CCR8=1.50×10-9 and CXCR3=2.60×10-4, respectively, compared to healthy donor group). Recalcitrant DRESS patients had considerably higher serum levels of CCL1 and CXCL10, CCR8 and CXCR3 ligands at week 8 after onset than rapid-responders. Recalcitrant DRESS patients had significantly higher proportions of CD8+central memory T, CD8+CD69+GNLY+effector memory T, and CD4+Th2+CCR8+ cells compared to rapid-respond DRESS patients (all P <0.05). Recalcitrant DRESS patients have IgG-anti-HES6 autoantibodies with uncertain clinical relevance. In the in vitro T cell blocking experiment, new Janus kinase inhibitors markedly reduced CCL1 and CXCL10 secretions in recalcitrant DRESS patients. After JAK inhibitor treatment, plasma CCL1 and CXCL10 levels dropped rapidly.Conclusion and Suggestion：The CCR8/CCL1 and CXCR3/CXCL10 axis is associated with the pathogenesis of recalcitrant DRESS, potentially through the recruitment of memory T cells, leading to recalcitrant DRESS and possibly related to long-term autoimmune sequelae. JAK inhibitors could be one of the treatment options for such patients.