A COMPARISON OF RECURRENT AND PRIMARY HERPES-SIMPLEX KERATITIS IN NIHINBRED MICE

Herpes simplex virus (HSV) infection is one of the leading causes of c orneal blindness. This study compared the clinical, virologic, and imm unopathologic features of primary and recurrent murine models of herpe s simplex keratitis (HSK) in the National Institutes of Health (NIH) i nbred mouse strain. Primary infection resulted in multiple epithelial dendrites, followed by diffuse stromal opacification, symptoms that do not mimic what is seen in human HSK. In contrast, recurrent infection presented clinical features that included microdendrites, focal strom al opacities, disciform endotheliitis, and corneal neovascularization, which were similar to those observed in human disease. Immunohistoche mical characterizations indicated that the number and duration of T ce lls and macrophages in recurrent HSK resemble those observed in primar y disease. Results also indicated that the amount of infectious virus detected in the cornea during primary and recurrent disease was simila r. However, when corneas were stained for HSV-I antigens, mice with pr imary HSK displayed diffuse HSV antigen expression throughout the corn ea, whereas HSV antigens were more focally distributed in recurrent di sease. These data suggest that the clinical differences between the re current and primary herpetic keratitis may, in part, reflect the diffe rent distribution of HSV-1 antigens within the cornea.