Fig. 7.

Double silencing of Erk1/2 and S6K1 powerfully inhibits hsBAFF-stimulated B-cell viability/survival enhanced by IL-2, IL-4, IFN-γ, or TNF-α. Raji cells were infected with lentiviral shRNAs to S6K1/Erk1/2 and GFP, respectively. (A) The cells were subjected to Western blotting. The blots were probed for β-actin as a loading control. Similar results were observed in at least three independent experiments. (B and C) The cells were treated with/without hsBAFF (0.25 μg/ml) in the presence or absence of IL-2 (50 ng/ml), IL-4 (25 ng/ml), IFN-γ (100 ng/ml) or TNF-α (50 ng/ml) for 48 h, followed by cell viability using MTS assay (B) and relative number of live cells using trypan blue exclusion assay (C). Results are presented as mean ± S.E. (n = 5). ^ap < 0.05 difference with control group; ^bp < 0.05, difference with 0.25 μg/ml hsBAFF group; ^cp < 0.05 S6K1/Erk1/2 shRNA group vs GFP shRNA group.