Type-specific identification of herpes simplex and varicella-zoster virus antigen in autopsy tissues

To identify antigens of herpes simplex virus (HSV) types 1 and 2 and varicella-zoster virus (VZV) in human tissue, polyclonal antisera and an immunoperoxidase method were used to examine formalin-fixed, paraffin-embedded tissues from autopsy cases and experimentally infected animals. These antisera readily distinguished between HSV and VZV antigen, with no evident cross-reactivity. Antiser ato HSV-1 and HSV-2 were more strongly reactive with antigen of the homologous virus than with that of heterologous virus. This difference in immunoreactivity was used to discriminate between HSV-1 and HSV-2 antigens in experimentally infected animal tissues containing HSV antigens of known type and, by extrapolation, to distinguish between these antigens in human autopsy tissues. Thus, with appropriate antisera and tissue controls, HSV-1, HSV-2, and VZV can be identified in paraffin sections.