Orfali Raquel L, Sato Maria N, Santos Vanessa G, Titz Tiago O, Brito Cyro A, Duarte Alberto J S, Takaoka Roberto, Aoki Valéria
Department of Dermatology, University of Sao Paulo School of Medicine, Sao Paulo, Brazil.
Laboratory of Medical Investigation in Dermatology and Immunodeficiency, University of Sao Paulo School of Medicine, Sao Paulo, Brazil.
Int J Dermatol. 2015 Aug;54(8):898-904. doi: 10.1111/ijd.12533. Epub 2014 Oct 14.
Atopic dermatitis (AD) is a chronic recurrent inflammatory disease, with prevalence of about 10-20% in children and 1-3% in adults. Staphylococcus aureus is present in 80-100% of skin from atopic patients and is related to worsening of the disease by the action of enterotoxins. The aim of this study was to evaluate the profile of anti-Staphylococcus aureus enterotoxin B (SEB) antibody isotypes and IgG subclass levels in adult AD.
We selected 38 patients with AD, diagnosed by Hanifin and Rajka's criteria, aged between 18 and 65, and 26 healthy controls (HC). The severity of the disease was established according to the Eczema Area and Severity Index and patients graded as mild (28%), moderate (58%), and severe (14%). Sera were assessed for IgG subclasses, IgA, IgM, and IgE against SEB by ELISA.
Elevated circulating IgE and IgG4 anti-SEB antibody levels associated with decreased IgA and IgM levels were detected in patients with AD, when compared to HC individuals. The severity of AD was related to low IgG1 and IgG3 levels and a high IgE antibody response to SEB. Interestingly, absence of IgG4 response to SEB was lower in patients with AD (2.63%), when compared to controls (34.6%), while a similar absence was detected for IgG1 and IgE antibodies (AD, 23.3 and 18.4% vs. HC, 38.5 and 19.2%).
Our findings evidenced a contributing role for IgG4 and IgE antibodies in AD pathogenesis, which are triggered by staphylococcal superantigens.
特应性皮炎（AD）是一种慢性复发性炎症性疾病，儿童患病率约为10%-20%，成人患病率为1%-3%。金黄色葡萄球菌存在于80%-100%的特应性患者皮肤中，通过肠毒素的作用与疾病恶化相关。本研究的目的是评估成年AD患者抗金黄色葡萄球菌肠毒素B（SEB）抗体亚型和IgG亚类水平。
我们选择了38例根据Hanifin和Rajka标准诊断的AD患者，年龄在18至65岁之间，以及26名健康对照（HC）。根据湿疹面积和严重程度指数确定疾病严重程度，患者分为轻度（28%）、中度（58%）和重度（14%）。通过ELISA检测血清中针对SEB的IgG亚类、IgA、IgM和IgE。
与HC个体相比，AD患者中检测到循环IgE和抗SEB IgG4抗体水平升高，同时IgA和IgM水平降低。AD的严重程度与低IgG1和IgG3水平以及对SEB的高IgE抗体反应相关。有趣的是，与对照组（34.6%）相比，AD患者中对SEB无IgG4反应的比例较低（2.63%），而IgG1和IgE抗体的类似无反应情况在AD患者中为23.3%和18.4%，在HC中为38.5%和19.2%。
我们的研究结果证明了IgG4和IgE抗体在AD发病机制中的作用，它们由葡萄球菌超抗原触发。
