Figure 5. BAFF promotes ALL viability.
(A) Long-term viability of ALL (P-2) cells cultured on OP9 or MEFs. (B) Western blot analysis for BAFF in ALL P-2, US.7 and stromal OP9 and MEF cells. U937, positive human control; mouse spleen, positive murine control. Tubulin, loading control. (C, left) Viability of US.7 in the presence or absence (control) of added recombinant BAFF (1 μg/ml) in the absence of stroma. *p<0.05. (C, right) Viability of US.7 incubated with anti BAFF-R neutralizing antibody (5 μg/ml) as indicated. *p<0.05. (D) Viability of US.7 and P-2 (3×106 cells/ml) cultured in the absence of stroma with BAFF (200 ng/ml), BCMA-Fc (10 μg/ml), human-Ig-Fc (20 μg/ml) or both BAFF (200 ng/ml) and BCMA-Fc (10 μg/ml). *p<0.05 for BCMA-Fc compared to human-Ig-Fc, considered significant.