Hairy leukoplakia: Epstein-Barr virus receptors on oral keratinocyte plasma membranes.

Hairy leukoplakia (HL) is an oral white lesion associated with, and probably caused by, the Epstein-Barr virus (EBV) among persons who are seropositive for infection with human immunodeficiency virus. A unique feature of HL is its localization to the lateral portion of the tongue. To determine site differences for EBV receptors according to epithelial phenotype, these receptors were mapped in oral mucosa with the use of monoclonal antibodies HB5 and B2(specific for the Complement Fraction 3d/EBV receptor on B lymphocytes). Immunoperoxidase and immunofluorescence techniques were employed with the use of both cytologic suspensions and frozen tissue sections of oral epithelium. Pericellular plasma membrane immunoreactants were localized to upper spinous layer cells of the parakeratin phenotype; basal and parabasilar layers as well as all strata of orthokeratinized epithelia were negative. Those cells harboring EBV DNA as detected by in situ hybridization corresponded to cells with C3d/EBV receptors.