EXPRESSION OF EPSTEIN-BARR-VIRUS PROTEINS IN PRIMARY CNS LYMPHOMA IN AIDS PATIENTS

We examined the expression of the Epstein-Barr virus (EBV)-induced pro teins (LMP [latent membrane protein], EBNA-2, and CD23) and a lytic pr otein, viral capsid antigen (VCA), in five acquired immune deficiency syndrome (AIDS)-related primary CNS lymphomas (PCNSLs). We compared th at expression with the expression of the same proteins in PCNSL from s ix immunocompetent patients and severe combined immune deficiency (SCI D) mouse brains injected with EBV-infected lymphoblastoid cell lines ( LCLs). Brain biopsy tissue from an AIDS patient with progressive multi focal leukoencephalopathy (PML) and a normal brain was also studied. T hree of the AIDS PCNSLs expressed both human immunoglobulin kappa and lambda light chains and two expressed lambda light chain only. All non -AIDS-related PCNSLs expressed a single light-chain isotype. All five AIDS-related PCNSLs expressed LMP-1 (>40%), EBNA-2 (>60%), and VCA (1 to 5%) of tumor cells. These proteins were similarly expressed in the SCID/human chimeras. None of the PCNSLs from immunocompetent subjects, the normal brain, or the brain of the patient with PML expressed thes e proteins. PCNSL in AIDS patients bears greater similarity to EBV-inf ected LCLs than to PCNSL from immunocompetent patients.