角质形成细胞在银屑病发病机制中的作用研究

As the major constituent of the epidermis, keratinocytes are believed to be crucial in both the early stages of psoriasis pathogenesis and later amplification of chronic inflammatory circuits. Psoriasis generally manifests as chronic inflammation of the skin and is characterized by hyperproliferation and altered differentiation of epidermal keratinocytes. This application focus on psoriatic epidermal keratinocytes from nonlesional, perilesional and lesional skin, as compared with epidermal keratinocytes from eczema and healthy skin. Potential biomarkers of psoriatic keratinocytes should be identified using various technologies including transcriptomics, proteomics and metabolomics, in combination with investigation on molecules in extracellular vesicles secreted by keratinocytes and data completed by genome-wide association study (GWAS). Furthermore, cytokines and chemokines and their receptors in keratinocytes should be determined. These research could screen out the most significant biomarkers expressed by psoriatic epidermal keratinocytes. By studying the effect of infection, in vitro wound and medicines on key biomarkers of epidermal keratinocytes and cells co-cultured with vascular endothelial cells and dermal T cells, we hope to find the most significant changed biomarkers from keratinocytes in the initiation, maintenance and regression of psoriasis. Next, knock-in and knockout mice are constructed to clarify the functions of screened key biomarkers and make out their role in the pathogenesis of psoriasis. Finally, whether keratinocytes themselves have their share in initiation and/or propagation of psoriasis should be identified.

银屑病表皮角质形成细胞可能既是银屑病发生的“始作俑者”，又是银屑病发展的“终末表现者”，其异常增生是银屑病的主要特征。本研究以角质形成细胞为研究对象，通过比较分析银屑病非皮损区、临近皮损区、皮损区与正常皮肤及慢性湿疹患者皮损区表皮及角质形成细胞蛋白质组学、转录组学、代谢组学以及角质形成细胞分泌胞外囊泡中分子的差异，结合既往GWAS研究发现的易感基因、细胞因子和趋化因子及其受体，筛选出银屑病角质形成细胞表达的优势基因，确定与银屑病角质形成细胞改变最相关的关键分子。以感染、创伤、药物、血管内皮细胞及T细胞等与角质形成细胞共孵育/共培养，发现银屑病角质形成细胞激发、维持、转归过程中的特异性优势标记物的变化。在此基础上构建基因敲入或敲除小鼠，进行功能研究，确定发现的关键分子在银屑病发病中的作用及机制，进一步明确银屑病角质形成细胞变化的特异性分子基础，确定角质形成细胞在银屑病中的作用。

银屑病表皮角质形成细胞既是银屑病发生的“始作俑者”，又是银屑病发展的“终末表现者”，其异常增生是银屑病的主要特征。本研究以角质形成细胞为研究对象，通过比较银屑病非皮损区、临近皮损区、皮损区与正常皮肤表皮角质形成细胞蛋白质组学、转录组学以及角质形成细胞分泌胞外囊泡中分子的差异，并进行差异蛋白GO分析和KEGG通路分析，找到银屑病发病机制中可能发挥重要作用的蛋白及关键作用分子：OAS家族蛋白。2’-5’寡聚腺苷酸合成酶（OAS）是一种干扰素诱导产生的抗病毒蛋白，在机体的抗病毒免疫过程中发挥着重要作用。人OAS 蛋白家族包括 OAS1、OAS2、OAS3 和 OASL。本研究对OAS家族的OAS1、OAS2、OAS3成员进行进一步探索，发现其成员OAS2在疾病发生发展中可能发挥重要作用。本研究发现，银屑病皮肤中OAS2蛋白与其疾病严重程度（PASI和BSA评分）呈正相关。本研究还明确了OAS家族在皮肤组织中的细胞来源以及OAS家族蛋白在银屑病患者血清中的变化。此外，本研究探索了I 型干扰素以及JAK 抑制剂对正常人表皮角质形成细胞中OAS1、OAS2 和 OAS3表达水平的影响，同时，进一步探索了敲低OAS家族蛋白OAS1、OAS2和OAS3对正常人表皮角质形成细胞中JAK-STAT通路的影响及细胞增殖和周期的影响。