Jang Jae-Hyuk, Yang Eun-Mi, Lee Youngsoo, Ye Young-Min, Moon Jiyoung, Ryu Min Sook, Park Hae-Sim
Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, South Korea.
World Allergy Organ J. 2022 Feb 12;15(2):100629. doi: 10.1016/j.waojou.2022.100629. eCollection 2022 Feb.
IgE bound on the surface of mast cells contributes to the pathogenesis of chronic spontaneous urticaria (CSU). Atopy is a predisposing factor for CSU, where omalizumab is a widely used monoclonal antibody to control urticaria symptoms via capturing serum free IgE. However, the role of serum free IgE is not clarified in CSU. The present study evaluated the clinical relevance of serum free IgE in patients with CSU.
Eighty-eight patients with CSU and 76 healthy controls (HCs) were enrolled in this study. Serum total and ()-specific IgE levels were measured by ImmunoCAPs. The serum free IgE levels were measured by ELISA using a novel IgE, and their associations with clinical parameters, including urticaria activity score (UAS), were evaluated. Changes in serum free and total IgE levels after omalizumab treatment were observed in 23 CSU patients in comparison between responders (≥50% reduction in UAS) and non-responders (<50% reduction).
Significantly higher serum free/total IgE levels were noted in CSU patients than in HCs with a positive correlation between the 2 values ( = 0.87, < 0.001). Among CSU patients, atopics had significantly higher serum free IgE levels than non-atopics, while no associations were noted with UAS, urticaria duration, or the results of serum ANA or autologous serum skin tests. In addition, there were no significant changes in serum free IgE levels during 12 months of omalizumab treatment. No significant differences were noted in serum free/total IgE levels or clinical parameters between responders and non-responders, while responders have higher serum -specific IgE level and its ratio to serum free/total IgE level than non-responders ( < 0.05, respectively).
These findings suggest that increased serum free IgE may be involved in the development of CSU by activating mast cells, especially in atopics. High specific IgE level and its ratio to serum free IgE level may be a potential biomarker for predicting favorable responses to omalizumab in CSU.
结合在肥大细胞表面的IgE促成了慢性自发性荨麻疹（CSU）的发病机制。特应性是CSU的一个易感因素，其中奥马珠单抗是一种广泛使用的单克隆抗体，可通过捕获血清游离IgE来控制荨麻疹症状。然而，血清游离IgE在CSU中的作用尚未阐明。本研究评估了CSU患者血清游离IgE的临床相关性。
本研究纳入了88例CSU患者和76例健康对照（HCs）。采用免疫化学发光法测定血清总IgE和特异性IgE水平。使用一种新型IgE通过酶联免疫吸附测定法（ELISA）测定血清游离IgE水平，并评估其与包括荨麻疹活动度评分（UAS）在内的临床参数的相关性。观察23例CSU患者在奥马珠单抗治疗后血清游离和总IgE水平的变化，并比较反应者（UAS降低≥50%）和无反应者（UAS降低<50%）。
CSU患者的血清游离/总IgE水平显著高于HCs，且二者呈正相关（r = 0.87，P < 0.001）。在CSU患者中，特应性患者的血清游离IgE水平显著高于非特应性患者，而与UAS、荨麻疹病程或血清抗核抗体（ANA）及自体血清皮肤试验结果无关。此外，在奥马珠单抗治疗的12个月期间，血清游离IgE水平无显著变化。反应者和无反应者之间的血清游离/总IgE水平或临床参数无显著差异，但反应者的血清特异性IgE水平及其与血清游离/总IgE水平的比值高于无反应者（P均< 0.05）。
这些发现表明，血清游离IgE增加可能通过激活肥大细胞参与CSU的发生发展，尤其是在特应性患者中。高特异性IgE水平及其与血清游离IgE水平的比值可能是预测CSU患者对奥马珠单抗治疗反应良好的潜在生物标志物。
