Biological aspects of Epstein-Barr virus (EBV)-infected lymphocytes in chronic active EBV infection and associated malignancies.

Most primary Epstein-Barr virus (EBV) infections are clinically inapparent, but occasionally EBV infection can cause acute infectious mononucleosis. EBV has been linked to a variety of hematologic and non-hematologic malignancies. Chronic active EBV (CAEBV) infection designates a recently identified EBV-associated syndrome characterized by a variety of serious hematological disorders, including malignant lymphoma. EBV was found to infect circulating T- and/or NK-cells in patients with CAEBV infection. These EBV-infected T- and/or NK-cells express EBNA-1, LMP-1, and LMP-2A, a type II form of EBV latency, which is also observed in nasopharyngeal carcinoma (NPC), Hodgkin's disease (HD), and peripheral T-cell lymphoma. CAEBV infections may thus represent a subset of EBV-associated T- and/or NK-cell lymphoproliferative disorders.