Localization of 3H-thymidine-labeled HSV-1 in latently infected rabbit trigeminal ganglion cells.

Although current data favor conservation of virus in a nonreplicating form during latency, the actual host cell-virus relationship during this quiescent period remains an enigma. The purpose of this study was to develop a highly specific probe for direct localization of the HSV type 1 (HSV-1) genome in an animal model that closely mimics human disease. Tritium-labeled HSV-1 was inoculated onto trigeminal ganglion (TG) neurons in vitro and onto New Zealand white rabbit corneas in vivo. During acute infection in vivo and after establishment of latency in vivo or suppressed infection in vitro the TG neurons were processed for autoradiography. Silver grains were localized over nuclei of 8-10% of TG neuron cell bodies during suppressed infection in vitro. Acute infection in vivo resulted in the localization of label over 5-10% of neuron cell bodies and satellite cells per section. During latency the label appeared over nuclei of 1-10% of TG bodies per section. This study shows that directly labeled HSV-1 can be found in TG neuron nuclei both in vivo and in vitro. It also suggests that HSV genetic material is lost from certain neurons when latency is established.