Extraneuronal herpetic latency: animal and human corneal studies

HSV DNA has been previously detected by both in situ and dot blot hybridization in neuronal tissues latently infected with herpes simplex virus (HSV), but not in extraneuronal tissues. The present study, using dot blot hybridization with a cloned full-length HSV DNA probe and subtractive hybridization assays for detecting HSV RNA, reveals both the presence and activity of the HSV genome in 100% of HSV latently infected rabbit corneas tested. Studies on human herpetic corneas taken at keratoplasty using slot blot hybridization with a cloned full-length HSV DNA probe demonstrated positive binding (hybridization) to the probe in 50% of samples tested but no binding to normal human control DNA. These studies confirm earlier, less sensitive virus recovery assays and implicate the cornea as an extraneuronal site of HSV latency and reactivation.