Immunohistochemical evaluation of murine HSV-1 keratouveitis.

The intraocular inflammatory reaction in a murine model of herpes simplex keratouveitis was studied using immunohistochemical techniques. 5 x 10(5) PFU of HSV-1 (Stewart strain) was applied to the abraded cornea of BALB/c mice. The subsequent development of keratouveitis was documented by sequential examination, conventional histology and immunohistochemical staining of frozen sections with the following monoclonal antibodies: Thy-1, Lyt-1, Lyt-2, Ia, Mac-1 and Lyb-8.2. At one week (in the early stage) there was moderate central corneal edema with inflammatory cell infiltration, consisting of a predominance of polymorphonuclear leukocytes, with the appearance of helper/inducer T-cells(Th/i). At two weeks (in the middle stage), a geographic corneal ulcer developed and the majority of inflammatory cells were still polymorphonuclear leukocytes. However, there was a further increase in the Th/i cell population, with the first appearance of B-cells. At three weeks (in the late stage), a dense stromal corneal scar was observed and there was a decrease in the inflammatory cell population, with the predominant cell being the B-cell. Throughout the evolution of HSV-1 keratouveitis, a mild inflammatory reaction was observed in the uvea. However, the number of inflammatory cells present was too small to allow more definitive characterization. Patchy Ia staining which is noted in the normal choroid increased markedly throughout the keratouveitis.