Johansson Catharina, Ahlborg Niklas, Andersson Anna, Lundeberg Lena, Karlsson Maria A, Scheynius Annika, Tengvall Linder Maria
Clinical Allergy Research Unit, Department of Medicine Solna, Karolinska Institutet and University Hospital, Stockholm SE-171, Sweden.
Int Arch Allergy Immunol. 2009;150(1):51-8. doi: 10.1159/000210380. Epub 2009 Apr 2.
Atopic eczema is a chronic inflammatory skin disease in which several subgroups of cases can be identified. Atopy patch testing (APT) reveals allergen sensitization also in atopic eczema patients devoid of detectable allergen-specific IgE, suggesting the importance of factors other than IgE in the reaction. Here we investigate the relationship between APT reactions and allergen-specific peripheral IgE and T cell reactivity in atopic eczema patients.
Adult patients with atopic eczema (n = 64) and healthy controls (n = 24) were analyzed for reactivity to Malassezia sympodialis extract by APT, measurement of specific plasma IgE and in vitro determination of the frequency of allergen-reactive peripheral blood mononuclear cells producing interleukin-4 and interleukin-5 using the ELISpot method.
When combining the results of the APT, IgE measurements and the ELISpot analyses, reactivity to M. sympodialis was found in a majority of the atopic eczema patients (69%), whereas the healthy controls were negative throughout. T cell reactivity to M. sympodialis, manifested by production of both interleukins 4 and 5, was highly predictive for a positive APT reaction and displayed a strongly positive correlation with the APT score. In contrast, the allergen-specific IgE levels did not predict the APT outcome, and no correlation could be found between the IgE levels and the APT score.
Peripheral allergen-specific T helper 2 cell-mediated reactivity appears to be required for a positive APT reaction to M. sympodialis. The diagnostic potential of measuring peripheral allergen-specific T cell responses should be considered in atopic eczema.
特应性皮炎是一种慢性炎症性皮肤病，可分为几个亚组。特应性斑贴试验（APT）显示，在没有可检测到的过敏原特异性IgE的特应性皮炎患者中也存在过敏原致敏现象，这表明IgE以外的因素在该反应中具有重要作用。在此，我们研究了特应性皮炎患者中APT反应与过敏原特异性外周血IgE及T细胞反应性之间的关系。
通过APT分析、特异性血浆IgE测定以及使用酶联免疫斑点法（ELISpot）体外测定产生白细胞介素-4和白细胞介素-5的过敏原反应性外周血单个核细胞频率，对64例成年特应性皮炎患者和24例健康对照进行了马拉色菌提取物反应性分析。
综合APT、IgE测量和ELISpot分析结果，发现大多数特应性皮炎患者（69%）对马拉色菌有反应，而健康对照均为阴性。对马拉色菌的T细胞反应性表现为白细胞介素4和5的产生，对阳性APT反应具有高度预测性，且与APT评分呈强正相关。相比之下，过敏原特异性IgE水平不能预测APT结果，且IgE水平与APT评分之间未发现相关性。
对马拉色菌的阳性APT反应似乎需要外周过敏原特异性辅助性T细胞2介导的反应性。在特应性皮炎中应考虑测量外周过敏原特异性T细胞反应的诊断潜力。
