HUMAN OROPHARYNGEAL LESIONS WITH A DEFECTIVE EPSTEIN-BARR-VIRUS THAT DISRUPTS VIRAL LATENCY

The Epstein-Barr virus (EBV), a human herpesvirus that is predominantl y latent after infection, can be induced to replicate by deleted, rear ranged EBV DNA from cultures of laboratory strain P3HR-1. Because muco sal surfaces are permissive of EBV replication, 101 oral biopsies from 70 Chinese and 5 American patients were examined for natural counterp arts to tissue culture defective virus (WZhet), using as marker the ab normal juxtaposition of BamHI W and Z EBV DNA restriction fragments. O f the 49 oral biopsies that contained EBV DNA, 12 (24%) had the rearra nged WZ fragment by polymerase chain reaction analysis: 3 (42%) of 7 E BV-positive epithelial dysplasias or carcinomas, 6 (38%) of 16 hairy l eukoplakias, and 3 (12%) of 25 nonmalignant salivary gland biopsies. A ccompanying viral replication was confirmed by in situ cytohybridizati on and demonstration of the linear configuration of the genome in sele ct WZhet-positive lesions. These findings indicate that defective EBV with the unusual property of disrupting EBV latency is prevalent in na tural infections and may contribute to EBV's pathogenic diversity.