title: Interferon-γ up-regulates major-histocompatibility-complex class I-related chain A expression and enhances major-histocompatibility-complex class I-related chain A-mediated cytolysis of human corneal epithelium by natural killer cells in vitro.
abstract: Natural killer (NK) cells are important in the ocular surface innate response against viral and bacterial infection. Major-histocompatibility-complex class I-related chain A (MICA) antigens are ligands of natural killer group 2D, an activating or coactivating receptor expressed on NK cells. Recent studies demonstrated that interferon-gamma (IFN-γ) could modulate MICA expression in tumor cells. However, little is known about MICA expression and regulation in human corneal epithelium. Our study assessed whether the proinflammatory cytokine, IFN-γ, affects MICA expression in human corneal epithelium. We identified low levels of surface MICA expression in corneal epithelium using flow cytometry. IFN-γ promoted surface MICA expression in corneal epithelium and increased soluble MICA levels in a dose-dependent manner. IFN-γ also enhanced NK cell-mediated cytotoxicity against the corneal epithelium. Anti-MICA antibodies could further block this process. In summary, we describe a novel IFN-γ function in the regulation of the innate response in ocular surfaces.
authors.affiliation: Department of Ophthalmology, Eye, Ear, Nose, and Throat Hospital, School of Shanghai Medicine, Fudan University, Shanghai, China.
authors.forename: Jiaxu
authors.initials: J
authors.lastname: Hong
authors.forename: Tingting
authors.initials: T
authors.lastname: Shao
authors.forename: Xinghuai
authors.initials: X
authors.lastname: Sun
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.forename: Jianjiang
authors.initials: J
authors.lastname: Xu
mesh_terms: D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000187:drug effects / Q000235:genetics; D019573:Epithelium, Corneal / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A; D007371:Interferon-gamma