| Autor: |
Boccellato, F., Anastasiadou, E., Rosato, P., Kempkes, B., Frati, L., Faggioni, A., Trivedi, P. |
| Jazyk: |
angličtina |
| Rok vydání: |
2007 |
| Předmět: |
|
| Zdroj: |
J. Virol. 81, 2274-2282 (2007) |
| Popis: |
Epstein-Barr virus (EBV)-negative diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma-derived cell lines infected in vitro with a recombinant EBV expressed type II/III latency. High expression of EBNA2 inversely correlated with expression of germinal center (GC)-associated genes, BCL6 and TCL1. The decreased expression of BCL6 appeared to be dose dependent, with almost complete abrogation in highly EBNA2-expressing clones. The role of EBNA2 in negative regulation of these genes was confirmed by transfection and in a hormone-inducible EBNA2 cell system. LMP1 transfection reduced expression of TCL1, but not of BCL6, in DLBCLs. The GC-associated gene repression was at the transcriptional level and CBF1 independent. A decrease in HLA-DR, surface immunoglobulin M, and class II transactivator expression and an increase in CCL3, a BCL6 repression target, was observed in EBNA2-expressing clones. Since BCL6 is indispensable for GC formation and somatic hypermutations (SHM), we suggest that the previously reported lack of SHM seen in EBNA2-expressing GC cells from infectious mononucleosis tonsils could be due to negative regulation of BCL6 by EBNA2. These findings suggest that EBNA2 interferes with the GC phenotype. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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