REPORTS derived from murine gammaherpesvirus68-infected mice. Journal of Virology. 70(9):6516-8. 10. Webster GA, Perkins ND. 1999. Transcriptional cross talk between NFkappaB and p53. Molecular and Cellular Biology. 19(5):3485-95. 11. Wu TT, Usherwood EJ, Stewart JP, Nash AA, Sun R. 2000. Rta of murine gammaherpesvirus 68 reactivates the complete lytic cycle from latency. Journal of Virology. 74(8):3659-67.
Figure 7: Immunoblot of TPA and/or Bay11-treated HE cell lysates. At 48 hours, there is an increase in lytic antigen with TPA treatment (lane 8 versus lane 3). Combination with Bay11 further increases lytic antigen (lane 8 versus lane 10).
sus uninduced samples, showing a better delineation between the latent and lytic state. Therefore, we have continued using this cell line to evaluate optimal reactivation conditions.
Conclusions In this study, we aimed to optimize cell culture conditions to induce lytic replication in MHV68-infected B cell lines. For the latently infected A20-HE cells, TPA-stimulated reactivation was enhanced with the addition of NF-kB inhibitors, supporting our model whereby NF-kB activation promotes latency by repressing lytic gene expression. The S11 and M12 cell lines can also be induced to reactivate; however, because there is a great deal of spontaneous reactivation, they may not be ideal for studying the role of NF-kB in reactivation. In the future, we plan to explore additional cell lines, further validate our findings and identify the viral genes that are regulated by NF-kB signaling.
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