[Epstein-Barr virus infection--a lympho- and epitheliotropic infection].

Epstein-Barr virus (EBV) has long been thought to be primarily a B-lymphotropic virus. This tropism becomes obvious in the association of the virus with diseases that become manifest in lymphoproliferative conditions, such as acute infectious mononucleosis or endemic Burkitt's lymphoma. In the course of mononucleosis, however, viraemia cannot be detected and B-lymphocytes infected with EBV in vitro produce only small amounts of the virus. In contrast, recent studies document that EBV replicates in the epithelial cells in the mouth, and pronounced secretion of virus can also be detected. Cells of the basal layer of the epithelium can be infected via the EBV-specific CR2 receptor. Upon mitosis of the cells of the basal layer, EBV genome in episomal form is partitioned to the daughter cell. On the other hand, differentiation and maturation of the epithelial cells is paralleled by active virus production. Thus, there is evidence that the epithelial EBV infection is the main factor in the persistence and production of EBV. Accordingly, the EBV infection of epithelial cells which can result in diseases, seems to be the primary process, leading to the infection of B-lymphocytes and then to other diseases. Diseases associated with infection of epithelial cells by EBV and diseases involving B-lymphocytes are discussed with reference to this idea.