THE ROLE OF NATURAL-KILLER-CELLS IN THE DEVELOPMENT OF HERPES-SIMPLEXVIRUS TYPE-1 INDUCED STROMAL KERATITIS IN MICE

Natural killer (NK) cells and acquired cell-mediated immunity effector cells (delayed type hypersensitivity (DTH) and cytotoxic T lymphocyte s (CTL)) have been reported to play a vital role in the defence of the host against tumour and viral infections in locations other than the eve. A vigorous cellular inflammatory response to viral infections of the cornea, however, with the attendant damage to the corneal clarity, has obvious evolutionary disadvantages, and a substantial body of evi dence indicates that in animals (e.g. mice) which are highly suceptibl e to inflammatory destruction of the cornea following corneal encounte r with herpes simplex virus, it is the animal's immunological/inflamma tory response which is responsible for the corneal damage. We examined the role of natural killer cells in the development of herpes stromal keratitis (HSK) in NK-deficient (C57BL/6J-bgj (beige)) mice and their NK-competent (C57BL/6J (black)) relatives. The beige (NK-deficient) m ice were just as resistant to HSK as were the black mice. We also stud ied the effects of NK cell depletion of BALB/c Igh-1 disparate congeni c mice. C.AL-20 (Igh-1d) mice are ordinarily highly susceptible to nec rotising HSK. In vivo NK-cell depletion in these mice significantly de creased the incidence and severity of HSK in these animals (p<0.0005). Corneas from untreated C.AL-20 mice contained T cells, macrophages an d NK cells. The corneal infiltrate from NK-depleted C.AL-20 mice consi sted of T cells and macrophages but no NK cells. These data indicate t hat NK cells are participants in the development of HSK in the murine model of this disease.