Ito K, Futamura M, Borres M P, Takaoka Y, Dahlstrom J, Sakamoto T, Tanaka A, Kohno K, Matsuo H, Morita E
Department of Allergy, Aichi Children's Health and Medical Center, Obu, Japan.
Allergy. 2008 Nov;63(11):1536-42. doi: 10.1111/j.1398-9995.2008.01753.x.
Gliadins have been implicated in immunoglobulin E (IgE)-mediated allergy to ingested wheat and omega-5-gliadin is known to represent a major allergen in wheat-dependent exercise-induced anaphylaxis. Less known is whether omega-5-gliadin is a clinically relevant allergen in children with immediate allergy to ingested wheat. This study investigates whether specific IgE antibodies to omega-5-gliadin (sIgE-omega-5-gliadin-ab) could be used as a marker for oral wheat challenge outcome in wheat-sensitized children. A secondary objective was to study whether the level of sIgE-omega-5-gliadin was related to symptom severity in children with a positive challenge test.
Serum samples from 88 children sensitized to wheat, of whom 35 underwent wheat challenge, were collected consecutively. sIgE-omega-5-gliadin-ab was related to a physician's diagnosis of wheat allergy and challenge symptoms.
The mean concentration of sIgE-omega-5-gliadin-ab was 7.25 kU(A)/l in patients with wheat allergy and 1.08 kU(A)/l in patients with no wheat allergy (P < 0.01). sIgE-omega-5-gliadin-ab was only detected in 12 of the non-wheat allergic children and 11 of them had a specific IgE to wheat below 1.30 kU(A)/l. Children reacting with severe symptoms upon challenge (n = 8) had increased levels of sIgE-omega-5-gliadin-ab compared to children with moderate, mild or no symptoms (P < 0.001).
The presence of sIgE-omega-5-gliadin-ab is related to the reaction level to wheat challenge outcome in wheat-sensitized children. The sIgE-omega-5-gliadin-ab was found to be associated with a strong convincing history of wheat allergy also in those cases when oral food challenge was avoided. The sIgE-omega-5-gliadin-ab level may serve as a marker for clinical reactivity in wheat-sensitized individuals.
麦醇溶蛋白与免疫球蛋白E（IgE）介导的摄入性小麦过敏有关，已知ω-5-麦醇溶蛋白是小麦依赖运动诱发过敏反应的主要过敏原。而ω-5-麦醇溶蛋白在摄入性小麦速发型过敏儿童中是否为临床相关过敏原则鲜为人知。本研究调查了针对ω-5-麦醇溶蛋白的特异性IgE抗体（sIgE-ω-5-麦醇溶蛋白抗体）能否作为小麦致敏儿童口服小麦激发试验结果的标志物。第二个目标是研究sIgE-ω-5-麦醇溶蛋白水平是否与激发试验阳性儿童的症状严重程度相关。
连续收集了88名小麦致敏儿童的血清样本，其中35名接受了小麦激发试验。sIgE-ω-5-麦醇溶蛋白抗体与医生对小麦过敏的诊断及激发试验症状相关。
小麦过敏患者中sIgE-ω-5-麦醇溶蛋白抗体的平均浓度为7.25 kU（A）/l，无小麦过敏患者中为1.08 kU（A）/l（P<0.01）。仅在12名非小麦过敏儿童中检测到sIgE-ω-5-麦醇溶蛋白抗体，其中11人的小麦特异性IgE低于1.30 kU（A）/l。与出现中度、轻度或无症状的儿童相比，激发试验时出现严重症状的儿童（n = 8）的sIgE-ω-5-麦醇溶蛋白抗体水平升高（P<0.001）。
sIgE-ω-5-麦醇溶蛋白抗体的存在与小麦致敏儿童对小麦激发试验结果的反应程度相关。在避免口服食物激发试验的情况下，sIgE-ω-5-麦醇溶蛋白抗体也与确凿的小麦过敏病史相关。sIgE-ω-5-麦醇溶蛋白抗体水平可作为小麦致敏个体临床反应性的标志物。
