[An immunoperoxidase study of early phase experimental retinitis induced by herpes simplex virus]

Herpes simplex virus type 1 (HSV-1) was intravitreally inoculated in domesticated rabbits, and retinitis was observed with the ABC-method using peroxidase-conjugated antibody. Trypsin digestion was used for antigen visualization. Three days after inoculation, although cell degeneration was not found in the retina, DAB was deposited on the inner limiting membrane and the nerve fiber layer, which corresponded to the basal side of Müller cells. These findings indicated that viral antigen was already present in the retina at this early stage. Four or five days after inoculation, numerous variously sized exudative retinal lesions were seen. In the small exudative foci, DAB deposition was restricted to only in the nuclei of the nerve cells of the inner nuclear layer, while it extended to the outer and inner retinal layer in the large exudative foci. These results suggested that when HSV-1 was injected intravitreally it invaded from the basal side of Müller cells to the inner nuclear layer, where it replicated. The virus spread to the outer nuclear layer and ganglion cells as infection proceeded.