PARALLEL EXISTENCE OF EPSTEIN-BARR-VIRUS (EBV) POSITIVE AND NEGATIVE CELLS IN A SPORADIC CASE OF BURKITT-LYMPHOMA

In the Burkitt lymphoma line Oma-BL1, EBV positive and negative cells coexist. We demonstrate that EBV positive and negative subclones are i dentical with respect to chromosome markers and HLA type and that the same c-myc rearrangement occurs in all the subclones. This shows that the tumor cells are derived from the same patient and are of monoclona l origin. In the positive subclones, the EBV genome was stably maintai ned in the episomal form. The EBV negative subclones could be derived from previously uncloned tumor cells in early passage, but not from th e EBV positive subclones.