DETECTION OF EBER-1 RNA IN PRIMARY BRAIN LYMPHOMAS IN IMMUNOCOMPETENTAND IMMUNOCOMPROMISED PATIENTS

Tissue from primary central nervous system lymphoma (PCNSL) which deve loped in five patients with acquired immune deficiency syndrome (AIDS) , nine patients without immunodeficiency, and two Epstein-Barr virus ( EBV)-positive control cell lines (B95-8 and Raji) were examined for th e presence of EBER-1 RNA. The tissues were hybridized with digoxigenin -labeled sense or anti-sense EBER-1 riboprobes. In all five AIDS-relat ed PCNSLs, strong hybridization signals were found with the EBER-1 ant i-sense probe. Signals could be eliminated by preincubation of the tis sues with RNase-A. Hybridization with the EBER-1 sense probe showed no signal. All PCNSLs from immunocompetent patients (five paraffin-embed ded, four frozen) showed no hybridization signals with EBER-1 sense or antisense probe but good hybridization signals with probes to immunog lobulin kappa or lambda light chain indicating RNA preservation. The p araffin-embedded B95-8-positive control cell-line showed positive hybr idization in most cells with the anti-sense EBER-1 probe, and up to on e percent of the cells had a weak signal with the sense probe. Most Ra ji cells showed a uniform signal with the anti-sense EBER-1 probe only . We conclude that, PCNSLs that arise in AIDS patients are associated with latent EBV infections, whereas PCNSLs from immunocompetent patien ts are not indicating a probable role for EBV in pathogenesis of these tumors.