[Recent studies on the distribution and immune characterization of dendritic cells in the corneal epithelium]

Langerhans cell-type dendritic cells (DCs) present in the corneal epithelium are capable of taking up, processing, and presenting antigens, leading to the initiation of T-lymphocyte responses. These cells are the professional antigen-presenting cells (APCs) of the corneal epithelium and serves as the critical sentinel cells of the immune system in the ocular surface. A recent study has demonstrated that normal limbal basal epithelium is in fact endowed with a small number of slow-cycling DCs with expression of a limbal stem cell marker, ABCG2. Furthermore, it has been found that central corneal inflammation induces recruitment of major histocompatibility complex (MHC) class II(+) DCs from limbal basal epithelium. These findings suggest that limbal basal epithelial DCs play an important role in corneal inflammatory reaction.