Immunohistopathologic findings in herpes simplex virus chorioretinitis in the von Szily model.

After anterior chamber inoculation of herpes simplex virus type 1 (HSV-1), some mice have a characteristic pattern of ocular disease, including ipsilateral anterior uveitis, relative sparing of the ipsilateral retina, and necrotizing contralateral chorioretinitis. It was reported previously that susceptibility to the contralateral chorioretinitis is associated with the Igh-1 locus; congenic mice differing at this locus have different rates of contralateral disease. The immunohistopathologic findings of this model in Igh-1 disparate congenic mice are reported after examining immune cell populations (CD4, CD8, Thy 1.2, Ia, Mac, and immunoglobulin G cells) in both ipsilateral and contralateral eyes and the recruitment kinetics of these cell types in various ocular tissues. In both HSV-susceptible BALB/c and HSV-resistant C.B-17 mice, the ipsilateral eye undergoes early cellular infiltration, and the contralateral retina is devoid of cells until day 10 postinoculation. In BALB/c mice, a late dramatic rise develops in Mac and Ia cells in the ipsilateral and contralateral choroid (P less than 0.005) compared with C.B-17 mice. The C.B-17 mice have an earlier, mild cellular infiltration of the uveal tract in the ipsilateral eye, abrogation of the late Mac and Ia cellular recruitment in the ipsilateral choroid, and an absent contralateral response. These strain-specific immunohistopathologic differences help to explain Igh-1-linked HSV retinitis patterns in this model.