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

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 cells (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. (Chin J Ophthalmol, 2018, 54: 149-153).