Palosuo K, Alenius H, Varjonen E, Kalkkinen N, Reunala T
Department of Dermatology, University of Helsinki and Hospital for Skin and Allergic Diseases, Helsinki, Finland.
Clin Exp Allergy. 2001 Mar;31(3):466-73. doi: 10.1046/j.1365-2222.2001.01023.x.
Patients with wheat-dependent, exercise-induced anaphylaxis experience severe allergic reactions when exercising after ingestion of wheat. The major wheat allergen associated with these reactions is a omega-5 gliadin, and patients following a gluten-free diet have remained free of symptoms. The aim of this study was to examine whether allergens cross-reacting with wheat omega-5 gliadin are present in rye, barley and oats. Sera from 23 adult patients with wheat-dependent, exercise-induced anaphylaxis were examined. Cereal allergens cross-reacting with wheat omega-5 gliadin were identified by immunoblot inhibition. The cross-reactive allergens were purified by gel filtration and reversed-phase chromatography and submitted to amino acid sequencing. Cross-reactivity was further studied by IgE ELISA and ELISA inhibition, and in vivo reactivity by skin prick testing. In immunoblotting rabbit anti-omega-5 gliadin antibodies bound to 70 kDa and 32 kDa proteins in rye and a 34-kDa protein in barley, but not to proteins in oats. N-terminal sequencing identified these proteins as rye gamma-70 secalin, rye gamma- 35 secalin and barley gamma-3 hordein, correspondingly. In ELISA 21/23 (91%) patients with wheat-dependent, exercise-induced anaphylaxis showed IgE antibodies to purified gamma-70 secalin, 19/23 (83%) to gamma-35 secalin and 21/23 (91%) to gamma-3 hordein. In ELISA inhibition omega-5 gliadin inhibited over 90% of the IgE binding of pooled patient sera to solid-phase gamma-secalins and gamma-3 hordein. Skin prick testing gave positive reactions to gamma-70 secalin in 10/15 (67%) patients, to gamma-35 secalin in 3/15 (20%) patients and to gamma-3 hordein in 7/15 (47%) patients. The results of this study show that gamma-70 and gamma-35 secalins in rye and gamma-3 hordein in barley cross-react with omega-5 gliadin, a major allergen in wheat-dependent, exercise-induced anaphylaxis. These findings suggest that also rye and barley may elicit symptoms in patients with wheat-dependent, exercise-induced anaphylaxis.
患有小麦依赖型运动诱发过敏反应的患者在摄入小麦后运动时会出现严重的过敏反应。与这些反应相关的主要小麦过敏原是一种ω-5醇溶蛋白，而遵循无麸质饮食的患者则没有症状。本研究的目的是检测黑麦、大麦和燕麦中是否存在与小麦ω-5醇溶蛋白发生交叉反应的过敏原。检测了23名患有小麦依赖型运动诱发过敏反应的成年患者的血清。通过免疫印迹抑制法鉴定了与小麦ω-5醇溶蛋白发生交叉反应的谷物过敏原。通过凝胶过滤和反相色谱法纯化交叉反应性过敏原，并进行氨基酸测序。通过IgE ELISA和ELISA抑制进一步研究交叉反应性，并通过皮肤点刺试验研究体内反应性。在免疫印迹中，兔抗ω-5醇溶蛋白抗体与黑麦中的70 kDa和32 kDa蛋白以及大麦中的34 kDa蛋白结合，但不与燕麦中的蛋白结合。N端测序确定这些蛋白分别为黑麦γ-70麦醇溶蛋白、黑麦γ-35麦醇溶蛋白和大麦γ-3大麦醇溶蛋白。在ELISA中，21/23（91%）患有小麦依赖型运动诱发过敏反应的患者显示出针对纯化的γ-70麦醇溶蛋白的IgE抗体，19/23（83%）针对γ-35麦醇溶蛋白，21/23（91%）针对γ-3大麦醇溶蛋白。在ELISA抑制试验中，ω-5醇溶蛋白抑制了合并患者血清与固相γ-麦醇溶蛋白和γ-3大麦醇溶蛋白的IgE结合的90%以上。皮肤点刺试验中，10/15（67%）的患者对γ-70麦醇溶蛋白呈阳性反应，3/15（20%）的患者对γ-35麦醇溶蛋白呈阳性反应，7/15（47%） 的患者对γ-3大麦醇溶蛋白呈阳性反应。本研究结果表明，黑麦中的γ-70和γ-35麦醇溶蛋白以及大麦中的γ-3大麦醇溶蛋白与ω-5醇溶蛋白发生交叉反应，ω-5醇溶蛋白是小麦依赖型运动诱发过敏反应中的主要过敏原。这些发现表明，黑麦和大麦也可能在患有小麦依赖型运动诱发过敏反应的患者中引发症状。
