银屑病不但对个人的心理和生活质量造成较大影响，而且会合并系统性疾病如代谢综合征及心血管疾病等。IL-17A在其发病中发挥重要作用。银屑病患者存在皮肤屏障功能障碍，紧密连接蛋白是皮肤屏障的重要组成分子。IL-17A对紧密连接蛋白的影响主要集中于血脑屏障的研究，而对皮肤屏障中紧密连接蛋白的调控及可能机制目前并不清楚。本研究拟通过外源性IL-17A和添加IL-17A抑制剂影响表皮角质形成细胞中的IL-17A表达，以跨膜电阻和旁细胞渗透量为指标评估细胞屏障功能，并观察ERK途径中信号蛋白的表达改变，同时以TEWL为观察指标,在动物实验中验证IL-17A调控紧密连接蛋白的重要成员claudin蛋白和皮肤屏障功能的作用机制，以进一步阐述IL-17A在银屑病中调控claudin和皮肤屏障功能的分子机制，能为皮肤屏障功能相关的药物开发、临床防治提供新的研究思路和作用靶点。

Psoriasis not only effect on psychology and life quality of patients, but also can coincident with systemic diseases such as metabolic syndrome and cardiovascular disease.IL-17A plays an important role in its pathogenesis. While the regulation of the protein in the skin barrier and the possible mechanism has not been clear yet. This application plan to regulate the expression of IL-17A in epidermal keratinocytes by incubation with exogenous IL-17A or IL-17A inhibitor, and evaluate the cellular barrier function by evaluating transepithelial electrical resistance (TER) and paracellualr permeability. The downstream ERK molecules are also to be investigated. Using transepidermal water loss (TEWL), animal experiments further verify that IL-17A regulates claudins and influences the skin barrier. Thus, the study will reveal the molecular mechanism of IL-17A on claudins and skin barrier function, and supply novel insights into clinical control of barrier function associated cutaneous disorders.