IDENTIFICATION AND CHARACTERIZATION OF HERPES-SIMPLEX VIRUS-SPECIFIC CD4(-CELLS IN CORNEAS OF HERPETIC STROMAL KERATITIS PATIENTS() T)

Herpetic stromal keratitis (HSK) is a corneal disease initiated by a h erpes simplex virus (HSV) infection with a postulated T cell-mediated immunopathology. To study the antigen specificity of cornea-infiltrati ng T cells in HSK patients, T cells were isolated and expanded by mito genic stimulation from corneas of 2 patients with HSV-1-mediated HSK, A substantial number of the T cell clones (TCCs) obtained from these T cell lines were HSV-specific. All HSV-specific TCCs were of the CD3()CD4(+)CD8(-) phenotype. These TCCs responded to autologous HSV-infect ed corneal keratocytes, which expressed HLA class II molecules followi ng incubation with interferon-gamma. Upon HSV-specific stimulation, al l TCCs secreted interleukin-4, interleukin-5, and interferon-gamma. Th e data presented suggest that HSV-specific CD4(+) T cells play a role in the immunopathogenesis of HSK in humans and that corneal keratocyte s may act as antigen-presenting cells in this local T cell response.