Komine Mayumi
Department of Dermatology, Jichi Medical University, Japan.
J Pharmacol Sci. 2009 Jul;110(3):260-4. doi: 10.1254/jphs.09r06fm.
Atopic dermatitis frequently accompanies bronchial asthma, allergic rhinitis, and allergic conjunctivitis, the pathogenesis of which has frequently focused on the immunological aspects; however, skin eruption in atopic dermatitis occurs mainly in the epidermis, whose barrier function and cytokine expression have been revealed to be abnormal. In addition, the epidermis contains Langerhans cells, antigen-presenting cells, which could be considered the sentinel of the immune system. Some atopic dermatitis patients have been revealed to have mutations or SNPs (single-nucleotide polymorphisms) in the filaggrin gene, which affect the epidermal barrier function. Proteinases in the epidermis are of importance in maintaining the epidermal barrier, abnormalities of which have been reported in atopic dermatitis. Abnormalities of various cytokines and chemokines produced by keratinocytes have also been reported. Thymic stromal lymphopoietin (TSLP) produced by keratinocytes has recently been a focus in atopic dermatitis. Adrenergic/cholinergic responses in the epidermis could also influence the pathogenesis of atopic dermatitis. Considering epidermal keratinocytes as a trigger of immune abnormalities, not only as a peripheral effector, would be important to further disclose the pathogenesis of this enigmatic disorder.
特应性皮炎常伴有支气管哮喘、过敏性鼻炎和过敏性结膜炎，其发病机制常聚焦于免疫学方面；然而，特应性皮炎中的皮疹主要发生在表皮，其屏障功能和细胞因子表达已被揭示存在异常。此外，表皮含有朗格汉斯细胞，即抗原呈递细胞，可被视为免疫系统的哨兵。一些特应性皮炎患者已被发现丝聚合蛋白基因存在突变或单核苷酸多态性（SNP），这会影响表皮屏障功能。表皮中的蛋白酶对于维持表皮屏障很重要，特应性皮炎中已报道存在其异常。角质形成细胞产生的各种细胞因子和趋化因子的异常也有报道。角质形成细胞产生的胸腺基质淋巴细胞生成素（TSLP）最近成为特应性皮炎的研究焦点。表皮中的肾上腺素能/胆碱能反应也可能影响特应性皮炎的发病机制。将表皮角质形成细胞视为免疫异常的触发因素，而不仅仅是外周效应器，对于进一步揭示这种疑难病症的发病机制很重要。
