Attempts to demonstrate virus-specific sequences in human tumors. IV. EB viral DNA in European Burkitt lymphoma and immunoblastic lymphadenopathy with excessive plasmacytosis.

Various biopsies from different European malignant lymphomas, two biopsies from nasopharyngeal carcinomas, and material from non-neoplastic lymph nodes were assayed for the presence of Epstein-Barr virus (EBV) DNA by nucleic acid hybridization. Reassociation kinetics of in vitro-labelled EBV DNA were studied in the presence of tumor DNA. The lymphomas tested included among others follicular lymphomas, germinocytomas, immunoblastic lymphomas and lymphoplasmacytoid immunocytomas. Epstein-Barr viral DNA was demonstrated within the two nasopharyngeal carcinoma biopsies as expected. A histologically typical Burkitt lymphoma as well as an immunoblastic lymphadenopathy with excessive plasmacytosis also contained EBV-DNA. The Burkitt biopsy revealed about 15 EBV genome equivalents per cell. Antibodies against EBV-specific antigens were highly elevated in the serum of this patient. The material of the patient with immunoblastic lymphadenopathy contained 2-3 EBV genome equivalents per cell.