Micro RNAs of Epstein-Barr Virus Promote Cell Cycle Progression and Prevent Apoptosis of Primary Human B Cells
Figure 6
Spontaneous apoptosis of primary B cells infected with prototype or miRNA-mutated EBVs.
To examine the spontaneous apoptosis of primary B cells early after infection, the samples as shown in Figure 5 were analyzed by FACS for Annexin-V binding and propidium iodide (PI) staining at different time points p.i.. (A) FSC and SSC characteristics of uninfected and prototype 2089 EBV-infected primary B cells on day 0 and day 5 p.i., respectively. To exclude subcellular debris but include highly granular, presumably dying or dead cells, only cells within the indicated gate were analyzed for their Annexin-V and PI staining. (B) Annexin V/PI staining analysis of B cells infected with 2089 EBV or miRNA mutants at different time points p.i.. One representative experiment out of three is shown. Cells in the AnnexinV−/PI− quadrants (red boxes) indicate surviving cells at each time point p.i.. (C) Summary of the data shown in (B). The proportion of live, AnnexinV−/PI− cells at each time point p.i. was calculated. Fewer live cells were detected after ΔmirBHRF1 or ΔmirALL EBV infection than after prototype 2089 or +mirBART EBV infection indicating an anti-apoptotic role of the BHRF1 miRNAs during the early phase of B cell infection. The error bars represent the standard deviation of the mean of three different experiments.