Wensing Marjolein, Knulst André C, Piersma Sander, O'Kane Francesca, Knol Edward F, Koppelman Stef J
Department of Dermatology/Allergology G02.124, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
J Allergy Clin Immunol. 2003 Feb;111(2):420-4. doi: 10.1067/mai.2003.61.
Serologic cross-reactivity among legumes has been described; however, it is rarely clinically significant. In this study 3 patients with a history of anaphylaxis to pea are described who subsequently had symptoms after ingestion of peanut.
We investigated whether the peanut-related symptoms were due to cross-reactivity between pea and peanut proteins.
Peanut-related symptoms were documented according to case history or double-blind, placebo-controlled food challenge results. Skin prick tests were performed, and specific IgE levels were determined for pea and peanut with the CAP system FEIA. IgE-binding proteins in pea and peanut were identified by using immunoblot analysis. Cross-reactivity was studied by means of immunoblot and ELISA inhibition studies with whole extracts and purified allergens.
Peanut-related symptoms consisted of oral symptoms in all patients, with additional urticaria and dyspnea or angioedema in 2 patients. All patients had a positive skin prick test response and an increased IgE level to pea and peanut. Immunoblotting revealed strong IgE binding to mainly vicilin in pea extract and exclusively to Ara h 1 in crude peanut extract. Immunoblot and ELISA inhibition studies with crude extracts, as well as purified proteins, showed that IgE binding to peanut could be inhibited by pea but not or only partially the other way around.
Clinically relevant cross-reactivity between pea and peanut does occur. Vicilin homologues in pea and peanut (Ara h 1) are the molecular basis for this cross-reactivity.
豆类之间的血清学交叉反应已有报道；然而，在临床上这种情况很少见。在本研究中，描述了3例有豌豆过敏史的患者，他们在食用花生后出现了症状。
我们调查了花生相关症状是否是由于豌豆和花生蛋白之间的交叉反应所致。
根据病史或双盲、安慰剂对照食物激发试验结果记录花生相关症状。进行皮肤点刺试验，并使用CAP系统FEIA测定豌豆和花生的特异性IgE水平。通过免疫印迹分析鉴定豌豆和花生中的IgE结合蛋白。采用免疫印迹和ELISA抑制试验，用全提取物和纯化过敏原研究交叉反应。
所有患者的花生相关症状均包括口腔症状，2例患者还伴有荨麻疹、呼吸困难或血管性水肿。所有患者的皮肤点刺试验均呈阳性，对豌豆和花生的IgE水平升高。免疫印迹显示，豌豆提取物中的主要过敏原伴刀豆球蛋白与IgE有强烈结合，而在粗制花生提取物中仅与Ara h 1有结合。用粗提取物以及纯化蛋白进行的免疫印迹和ELISA抑制试验表明，豌豆可抑制IgE与花生的结合，反之则不能或仅部分抑制。
豌豆和花生之间确实存在临床相关的交叉反应。豌豆和花生中的伴刀豆球蛋白同系物（Ara h 1）是这种交叉反应的分子基础。
