“…Epstein-Barr virus (EBV) infects and establishes latency in B lymphocytes (for reviews, see references 12, 15, and 27). The virus has been implicated in the etiology of malignancies such as Burkitt's lymphoma (BL) (6,11,18,28) and in lymphoproliferative diseases in the immunocompromised host, including posttransplant lymphoproliferative disorders (PTLDs) and AIDS-related lymphomas (1,2,8,10,16,25,28). The high rate of mortality associated with the development of PTLDs has prompted several groups to retrospectively analyze EBV load in peripheral blood, virus shedding, localization of in situ markers for virus (by using an EB-encoded RNA [EBER] probe), and the anti-EBNA specific antibody responses in efforts to identify prognostic markers of disease (14,19,20,31).…”