Department of Dermatology/Allergology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
Clin Exp Allergy. 2018 Jan;48(1):60-65. doi: 10.1111/cea.13030. Epub 2017 Sep 28.
Little is known on the clinical relevance of peanut 2S albumin Ara h 7.
To investigate the discriminative ability of Ara h 7 in peanut allergy and assess the role of cross-reactivity between Ara h 2, 6 and Ara h 7 isoforms.
Sensitization to recombinant peanut storage proteins Ara h 1, 2, 3, 6, and 7 was assessed using a line blot in sera from 40 peanut-tolerant and 40 peanut-allergic patients, based on food challenge outcome. A dose-dependent ELISA inhibition experiment was performed with recombinant Ara h 2, 6 and Ara h 7 isoforms.
For Ara h 7.0201, an area under the ROC curve was found of 0.83, comparable to Ara h 2 (AUC 0.81) and Ara h 6 (AUC 0.85). Ara h 7 intensity values strongly correlated with those from Ara h 2 and 6 (r = 0.81). Of all patients sensitized to 2S albumins Ara h 2, 6, or 7, the majority was co-sensitized to all three (n = 24, 68%), although mono-sensitization to either 2S albumin was also observed in selected patients (Ara h 2: n = 6, 17%; Ara h 6: n = 2, 6%; Ara h 7: n = 2, 6%). Binding to Ara h 7.0101 could be strongly inhibited by Ara h 7.0201, but not the other way around.
Specific IgE against Ara h 7.0201 has a predictive ability for peanut allergy similar to Ara h 2 and 6 and possesses unique IgE epitopes as well as epitopes shared between the other Ara h 7 isoform and Ara h 2 and 6. While co-sensitization to all three 2S albumins is most common, mono-sensitization to either Ara h 2, 6, or 7 occurs in selected patients, leading to a risk of misdiagnosis when testing for a single 2S albumin.
关于花生 2S 白蛋白 Ara h 7 的临床相关性知之甚少。
研究 Ara h 7 在花生过敏中的鉴别能力，并评估 Ara h 2、6 和 Ara h 7 同工型之间交叉反应的作用。
基于食物挑战结果，使用线印迹法在 40 名花生耐受和 40 名花生过敏患者的血清中评估重组花生贮藏蛋白 Ara h 1、2、3、6 和 7 的致敏情况。用重组 Ara h 2、6 和 Ara h 7 同工型进行剂量依赖性 ELISA 抑制实验。
对于 Ara h 7.0201，ROC 曲线下面积为 0.83，与 Ara h 2（AUC 0.81）和 Ara h 6（AUC 0.85）相当。Ara h 7 强度值与 Ara h 2 和 6 的强度值密切相关（r = 0.81）。在所有对 2S 白蛋白 Ara h 2、6 或 7 致敏的患者中，大多数患者同时对所有三种蛋白致敏（n = 24，68%），尽管在一些患者中也观察到对单一 2S 白蛋白的单致敏（Ara h 2：n = 6，17%；Ara h 6：n = 2，6%；Ara h 7：n = 2，6%）。Ara h 7.0101 的结合可以被 Ara h 7.0201 强烈抑制，但反之则不然。
针对 Ara h 7.0201 的特异性 IgE 对花生过敏具有与 Ara h 2 和 6 相似的预测能力，并且具有独特的 IgE 表位以及与其他 Ara h 7 同工型以及 Ara h 2 和 6 之间的共同表位。虽然最常见的是同时对所有三种 2S 白蛋白致敏，但在一些患者中也会出现对 Ara h 2、6 或 7 的单一致敏，这导致在检测单一 2S 白蛋白时存在误诊的风险。
