Varjonen E, Vainio E, Kalimo K, Juntunen-Backman K, Savolainen J
Department of Dermatology, Helsinki University Central Hospital, Finland.
Clin Exp Allergy. 1995 Nov;25(11):1100-7. doi: 10.1111/j.1365-2222.1995.tb03257.x.
Hypersensitivity to cereals may occur via inhalation or ingestion. Although cereals are essential in the daily nutrition, only little information is available of the allergens causing symptoms in patients with atopic dermatitis (AD).
The purpose of the present study was to analyse the IgE immune-response to various cereals and specific cereal fractions of wheat and oats in children with severe AD and correlate the results with challenge studies.
Skin-prick tests (SPT) with a NaCl suspension of wheat, oats, rice, corn, millet and buckwheat and the ethanol soluble gliadin fraction of wheat were performed to 34 wheat/oats challenge positive or negative children with AD. Simultaneously serum total IgE and specific IgE antibody radioallergosorbent test (RAST), levels to wheat, oats and gluten were determined. In addition serum samples of these 34 AD patients and five age matched controls were analysed with IgE immunoblotting using neutral and acidic protein extracts of wheat and oats.
From the 34 AD children 33 were SPT positive with wheat and 18 with oats. Positive RAST to wheat and oats could be detected in 32 and 30 samples respectively. From the oral wheat challenge positive children 12/14 appeared positive with gliadin SPT and revealed positive RAST to gluten, but each of the wheat challenge negative were negative in SPT with gliadin. In immunoblotting using neutral and acidic fractions of cereals the IgE binding with sera of challenge positive children showed the most intensive staining, but no correlation was found between different staining patterns and the clinical wheat sensitivity. The 26, 38 and 69 kDa bands in wheat and the 46 and 66 kDa in oats could be classified as major IgE binding proteins of these cereals (> 50% of the sera were positive). SPT with rice, corn, millet or buckwheat was positive in 16/34 patients.
Intensive IgE staining to neutral/acidic soluble proteins in wheat and oats was seen, with major IgE binding to 26, 38 and 69 kDa proteins in wheat and 46 and 66 kDa in oats, but no specific IgE staining patterns correlating with clinical cereal sensitivity were found. The strong association between the positive oral wheat challenge and the positive SPT with the ethanol soluble gliadin suggests that also gliadin is an important allergen in wheat-allergic children with AD. The allergens in rice, corn, millet and buckwheat should be better studied before they can be recommended as alternatives for cereal allergic children.
对谷物的超敏反应可能通过吸入或摄入发生。尽管谷物在日常营养中必不可少,但关于特应性皮炎(AD)患者出现症状的过敏原的信息却很少。
本研究的目的是分析重度AD儿童对各种谷物以及小麦和燕麦的特定谷物组分的IgE免疫反应,并将结果与激发试验相关联。
对34名小麦/燕麦激发试验阳性或阴性的AD儿童进行了小麦、燕麦、大米、玉米、小米和荞麦的氯化钠悬液以及小麦醇溶谷蛋白组分的皮肤点刺试验(SPT)。同时测定血清总IgE和针对小麦、燕麦和麸质的特异性IgE抗体放射变应原吸附试验(RAST)水平。此外,使用小麦和燕麦的中性和酸性蛋白提取物,通过IgE免疫印迹法分析了这34名AD患者和5名年龄匹配对照的血清样本。
34名AD儿童中,33名小麦SPT呈阳性,18名燕麦SPT呈阳性。分别在32份和30份样本中检测到针对小麦和燕麦的阳性RAST。在口服小麦激发试验阳性的儿童中,12/14名麦醇溶蛋白SPT呈阳性,且针对麸质的RAST呈阳性,但小麦激发试验阴性的儿童在麦醇溶蛋白SPT中均为阴性。在使用谷物中性和酸性组分的免疫印迹中,激发试验阳性儿童血清的IgE结合显示出最强的染色,但未发现不同染色模式与临床小麦敏感性之间存在相关性。小麦中的26、38和69 kDa条带以及燕麦中的46和66 kDa条带可被归类为这些谷物的主要IgE结合蛋白(>50%的血清呈阳性)。16/34名患者的大米、玉米、小米或荞麦SPT呈阳性。
观察到小麦和燕麦中对中性/酸性可溶性蛋白的强烈IgE染色,主要IgE与小麦中的26、38和69 kDa蛋白以及燕麦中的46和66 kDa蛋白结合,但未发现与临床谷物敏感性相关的特异性IgE染色模式。口服小麦激发试验阳性与醇溶谷蛋白SPT阳性之间的强关联表明,醇溶谷蛋白也是AD小麦过敏儿童的重要过敏原。在推荐大米、玉米、小米和荞麦作为谷物过敏儿童的替代品之前,应更好地研究它们的过敏原。