角膜朗格汉斯细胞在干眼发病机制中作用的研究进展

Research progress of corneal Langerhans cells＇ role in the pathogenesis of dry eye disease

干眼为目前发病率最高的眼表疾病，其核心病理机制为泪液渗透压升高及眼表慢性炎性反应。角膜朗格汉斯细胞是眼表免疫系统中的专职抗原提呈细胞，随着认识的深入，逐步发现其在眼表疾病过程中的双面性，既可进行抗原吞噬导致免疫耐受，又可完成抗原呈递导致免疫激活，进而引起效应T细胞放大炎性反应。以往对千眼炎性反应机制方面的研究主要着重于T淋巴细胞的作用，而对角膜朗格汉斯细胞研究较少。但实际上，角膜朗格汉斯细胞的功能状态对眼表免疫过程的发生、发展及转归有着深刻的影响。本文将对近年来角膜朗格汉斯细胞在干眼发病机制方面的研究进展进行总结，以期为临床开展相关研究提供参考。

Dry eye disease （DED） is the most common ocular surface diseasenowadays. DED can be divided into different types based on the pathogenesis. The progression of DED is strongly related to chronic ocular surface inflammation, regardless of the type of DED. The corneal Langerhans ceils （LC） are the dedicated antigen presenting cells in the ocular surface immune system. Along with further understanding of LC recently, its double-sided functions have been discovered： on one hand, LC phagocytize antigen and induce immune tolerance, and on the other hand, LC process and present antigen, and initiate immune response. Therefore, the functional status of LC is of profound impact on the progression and prognosis of DED. Previous researches on DED pathogenesis were mainly focused on T lymphocyte while the importance of LC have not been emphasized. This article reviews the researches on corneal LC in DED of recent years.