TRANSCRIPTION OF LATENT AND REPLICATIVE EPSTEIN-BARR-VIRUS GENES IN BONE-MARROW AND PERIPHERAL-BLOOD MONONUCLEAR-CELLS OF HEALTHY DONORS

Reverse-transcriptase polymerase chain reaction has been used to analy ze the expression of 2 latent genes (EBNA-1 and LMP-1) and one replica tive gene (BZLF-1) of Epstein-Barr virus in mononuclear cells from bon e marrow and peripheral blood of healthy donors. EBV-gene transcriptio n was detected in 8 out of 15 bone-marrow samples. Among these, 5 allo wed the detection of latency-associated transcripts in the absence of BZLF-1 expression, Only one sample showed positivity for expression of both latent and lytic genes. in 2 cases, BZLF-1 was the only transcri pt detected. In peripheral blood, 4 out of 7 samples showed evidence o f EBNA-1 transcription; LMP-1 was expressed in 5 samples, and in 2 cas es concomitant expression of EBNA-1 and BZLF-1 was detected, These res ults provide a direct demonstration by RT-PCR of EBV gene transcriptio n in bone-marrow-resident viral infected cells and suggest, in contras t to previous studies on peripheral blood, that LMP-1 and BZLF-1 are f requently transcribed also in absence of EBV-related disease. The hete rogeneous viral gene expression found makes it difficult to define a p attern of viral latency in vivo which coincides with that described fo r lymphoblastoid or Burkitt's-lymphoma cell lines at different stages of differentiation. (C) 1997 Wiley-Liss, Inc.