TWEAK/Fn14信号在组织炎症中发挥关键作用，但确切机制不清楚。我们前期研究提示，TWEAK/Fn14信号激活在不同炎症疾病动物模型中诱导角质形成细胞双向命运（增殖或凋亡）。因此本研究拟建立几种典型炎症微环境体外模型，探讨有关细胞因子对角质形成细胞表达TNFR亚型的影响；观察TWEAK刺激后TRAF2/c-IAP1复合物形成与泛素化水平；利用siRNA转染与质粒载体技术，分析TRAF2变化对TNFR表达及细胞周期相关蛋白Ras/ERK、cyclin/CDK等的作用。同时，还将利用杂交瘤筛选与真核表达技术，构建双效的Fn14-R2Fab及TWEAK-MV1耦合物，观察对体外炎症模型中角质形成细胞命运的纠偏效应，以及对K14-VEGF转基因小鼠的治疗作用。本研究将揭示TNFR1/2漂移与Fn14-TRAF2-TNFR效应轴介导TWEAK调控细胞双向命运的分子机制，并为治疗银屑病找到新靶点。

TWEAK/Fn14 pathway plays an important role in regional inflammation though its precise mechanism remains unclear. Previously, we demonstrated that TWEAK/Fn14 signaling induces either apoptosis or proliferation of keratinocytes depending on the murine inflammatory models. Such bidirectional modulation of cell fate correlates with inflammatory microenvironment. Therefore, this proposal is aimed to study the effect of cytokines and phenotype-related proteins on the expression of TNF receptors (TNFR) type 1 and 2 in the keratinocytes cultured in inflammatory models that mimic psoriatic, atopic dermatitis or lupus-like microenvironments. The formation and ubiquitination of TRAF2/c-IAP1 complexes will be observed in cells upon TWEAK stimulation. Also, both siRNA and plasmid vector transfection will be adopted for regulating tumor necrosis factor-associated factor 2 (TRAF2) expression while the changes of TNFR subtypes and cell cycle-related Ras/ERK and cyclin/CDK signals are to be determined. Moreover, the two conjugates of Fn14-R2Fab and TWEAK-MV1 that target TNFR2 and TRAF2/c-IAP1 respectively, will be constructed by selecting hydridoma clones and expressing eukaryotic plasmid vector. The influence of these conjugates on keratinocytes in inflammatory models will be analyzed accordingly. Finally, the therapeutic and side effects of two conjugates will be monitored on the K14-VEGF transgenic mice. The results from this study may not only elucidate the roles of TNFR1/2 shift and Fn14-TRAF2-TNFR axis in the bidirectional TWEAK modulation of keratinocyte fate, but also contribute to the development of novel therapeutic approaches for treating skin diseases such as psoriasis.