Role of epithelium in EBV persistence and pathogenesis of B-cell tumours.

EBV has long been thought to be primarily a B-lymphotropic virus. A manifestation of this tropism is the association of the virus with a variety of B-cell lymphoproliferative disorders and tumours. However, there is now considerable evidence to suggest that the permissive cell type for EBV replication is epithelial and that infection of B cells may be a secondary, and, from the point of view of the virus, an unimportant consequence. A re-evaluation of the role that epithelium plays in viral persistence and of the importance of the immune response in the development of persistent infection indicates that T-cell-mediated immunity to the epithelial infection is critical in maintaining the normal delicate balance between virus and host. It also suggests that uncontrolled EBV replication in pharyngeal epithelium may be central to the evolution of some (or all) EBV-associated lymphomas.