title: Roles of T-cells in the development of allergic conjunctival diseases.
abstract: Massive infiltration of eosinophils is the typical histopathologic feature of severe forms of allergic conjunctival diseases (ACDs) such as vernal keratoconjunctivitis. Although ACD is an antigen (Ag)-specific disease, eosinophils lack Ag-specific receptors. Therefore, my group studied the likely roles of immunocompetent cells bearing Ag-specific receptors in inducing conjunctival eosinophil infiltration in ACDs. To induce experimental conjunctivitis (EC), Brown Norway rats and C57BL/6 and Balb/c mice were passively immunized by the transfer of Ag-specific or primed IgE, splenocytes, or purified T-cells and then challenged with Ag in eyedrops. The transfer of Ag-primed splenocytes or T-cells, but not of Ag-specific IgE, induced conjunctival eosinophil infiltration. We also showed that soon after EC induction by T-cell transfer, activated Ag-specific T-cells infiltrated the conjunctiva. Moreover, when EC-developing animals were topically treated with the T-cell-specific immunosuppressants cyclosporin A and FK506, conjunctival eosinophil infiltration was abrogated. In addition, only the transfer of Ag-specific type 2 helper T-cells (TH2 cells), but not of type 1 helper T-cells or CD8 T-cells, could induce conjunctival eosinophil infiltration. Our data show that Ag-specific TH2 cells play a crucial role in inducing conjunctival eosinophil infiltration during the development of EC. It is necessary to elucidate the roles that conjunctival residential cells and immunocompetent cells other than T-cells play in the conjunctival eosinophil infiltration of EC.
authors: Department of Ophthalmology and Visual Science, Kochi Medical School, Kohasu, Oko-cho, Nankoku-City 783-8505, Japan. fukusima@kochi-u.ac.jp
authors: Atsuki
authors: A
authors: Fukushima
mesh_terms: D000818:Animals; D003228:Conjunctiva / Q000276:immunology / Q000473:pathology*; D003233:Conjunctivitis, Allergic / Q000276:immunology* / Q000473:pathology; D018450:Disease Progression; D004804:Eosinophils / Q000473:pathology; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*