Hansen T K, Bindslev-Jensen C, Skov P S, Poulsen L K
Food Allergy Unit, National University Hospital, Copenhagen, Denmark.
Clin Exp Allergy. 1996 Nov;26(11):1276-85. doi: 10.1111/j.1365-2222.1996.tb00525.x.
At present, several in vitro tests for immunoglobulin E (IgE)-mediated food allergy are available. An estimation of the diagnostic accuracy of the various tests used in predicting clinical sensitivity to codfish in a well-characterized allergic material is necessary.
To compare the diagnostic value of four specific IgE tests, and histamine release from basophils (HR) in identifying clinical type I allergy to codfish. As a true diagnosis, double-blind, placebo-controlled food challenges (DBPCFC) were employed.
Eight clinically codfish-allergic adult patients were investigated together with 30 codfish-tolerant control subjects for evidence of codfish-specific reactivity by Phadebas RAST (PHA), Pharmacia CAP System RAST (CAP), Magic Lite (ML) and HR. To characterize the diagnostic properties of a freshly prepared raw codfish extract, experiments were conducted employing an in-house radioallergosorbent test (RAST), the Maxisorp RAST (MAXI) and HR. Finally, protein profile and IgE-reacting allergens were detected by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting.
The sensitivities of HR with commercial extract and the three commercially available specific IgE analyses were 0.83 and 1.00 respectively. Specificities were 1.00 (HR) and 0.87-1.00 (specific IgE tests). Freshly prepared codfish extracts improved the sensitivity of HR. SDS-PAGE revealed approximately 29 bands (< 14.3-200 kDa) including a band of 12-13 kDa, and in immunoblotting 18 sera identified 17 IgE-binding bands. The protein migrating at 12-13 kDa was identified in the fresh codfish extract tested with sera from all clinical codfish allergics, while no significant reaction was seen in the control subjects.
Based on the small number of adult patients included in our study, the in vitro assays with commercial and fresh extracts have high sensitivity and are acceptable for screening for codfish allergy. Specificity of Phadebas, CAP, and our in-house RAST was less than unity, whereas ML and strong binding of IgE to a 12-13 kDa protein completely matches DBPCFC results, and thus seems sufficient for establishing the diagnosis.
目前，有几种针对免疫球蛋白E（IgE）介导的食物过敏的体外检测方法。有必要评估在一种特征明确的过敏物质中，用于预测对鳕鱼临床敏感性的各种检测方法的诊断准确性。
比较四种特异性IgE检测方法以及嗜碱性粒细胞组胺释放试验（HR）在识别对鳕鱼的临床I型过敏中的诊断价值。采用双盲、安慰剂对照食物激发试验（DBPCFC）作为确诊方法。
对8名临床诊断为对鳕鱼过敏的成年患者和30名对鳕鱼耐受的对照受试者进行研究，通过Phadebas RAST（PHA）、Pharmacia CAP System RAST（CAP）、Magic Lite（ML）和HR检测其对鳕鱼特异性反应的证据。为了表征新鲜制备的生鳕鱼提取物的诊断特性，采用内部放射变应原吸附试验（RAST）、Maxisorp RAST（MAXI）和HR进行实验。最后，通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和免疫印迹法检测蛋白质谱和IgE反应性过敏原。
使用商业提取物的HR以及三种市售特异性IgE分析方法的敏感性分别为0.83和1.00。特异性分别为1.00（HR）和0.87 - 1.00（特异性IgE检测）。新鲜制备的鳕鱼提取物提高了HR的敏感性。SDS-PAGE显示约29条带（<14.3 - 200 kDa），包括一条12 - 13 kDa的带，在免疫印迹中，18份血清鉴定出17条IgE结合带。在所有临床鳕鱼过敏患者血清检测的新鲜鳕鱼提取物中鉴定出迁移率为12 - 13 kDa的蛋白质，而在对照受试者中未观察到明显反应。
基于我们研究中纳入的成年患者数量较少，使用商业提取物和新鲜提取物的体外检测具有高敏感性，可用于鳕鱼过敏的筛查。Phadebas、CAP和我们的内部RAST的特异性小于1，而ML以及IgE与12 - 13 kDa蛋白质的强结合与DBPCFC结果完全匹配，因此似乎足以确立诊断。
