title: Murine keratocytes function as antigen-presenting cells.
abstract: Keratocytes express MHC class I molecules constitutively, and keratocytes stimulated with IFN-gamma express MHC class II molecules. Unstimulated keratocytes constitutively express B7-1 and ICAM-1, as well as low levels of CD40 and 4-1BBL. These findings indicate that keratocytes may deliver both antigen-specific and costimulatory signals to CD4(+) and CD8(+) T cells. To demonstrate that keratocytes expressing B7-1 provide a costimulatory signal to T cells, CD4(+) or CD8(+) mouse T cells were incubated with anti-CD3 mAb and irradiated keratocytes. Enhanced proliferation of both CD4(+) and CD8(+) T cells occurred, and could be inhibited by anti-B7-1 mAb, indicating T cell costimulatory activity by B7-1 on the keratocytes. To demonstrate that keratocytes can deliver an antigen-specific signal, CD4(+) and CD8(+) T cells from herpes-infected mice were incubated with HSV-1-infected, irradiated keratocytes. The resulting T cell proliferation and production of Th1 cytokines (IL-2, IFN-gamma) indicated T cell activation by antigens presented by the infected keratocytes. These results show that keratocytes in the corneal stroma of the mouse can function as antigen-presenting cells and, thus, may play a role in immune-mediated stromal inflammation such as herpetic stromal keratitis.
authors.affiliation: The Immunomodulation Research Center and Department of Biological Sciences, University of Ulsan, Ulsan, Korea.
authors.forename: S K
authors.initials: SK
authors.lastname: Seo
authors.forename: B M
authors.initials: BM
authors.lastname: Gebhardt
authors.forename: H Y
authors.initials: HY
authors.lastname: Lim
authors.forename: S W
authors.initials: SW
authors.lastname: Kang
authors.forename: S
authors.initials: S
authors.lastname: Higaki
authors.forename: E D
authors.initials: ED
authors.lastname: Varnell
authors.forename: J M
authors.initials: JM
authors.lastname: Hill
authors.forename: H E
authors.initials: HE
authors.lastname: Kaufman
authors.forename: B S
authors.initials: BS
authors.lastname: Kwon
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000502:physiology*; D015703:Antigens, CD / Q000032:analysis; D018122:B7-1 Antigen / Q000032:analysis; D051940:B7-2 Antigen; D019013:CD40 Antigens / Q000032:analysis; D002478:Cells, Cultured; D003315:Cornea / Q000166:cytology*; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007634:Keratitis / Q000276:immunology; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D017154:Stromal Cells / Q000502:physiology
chemical_list: D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; D019013:CD40 Antigens; C497965:Cd86 protein, mouse; D016207:Cytokines; D000949:Histocompatibility Antigens Class II; D008562:Membrane Glycoproteins