Nuclear CD40 synergistically enhance c-Rel–potentiated BLyS promoter activation in LBCL cells. (A) LBCL cells (FN) were cotransfected with 6xNF-κB-CD40L reporter and the expression vectors for c-Rel (pCMV-c-Rel, 5 μg), CD40wt (pcDNA3.1/myc/his-CD40, 5 μg), and CD40NLSmut (pcDNA3.1/myc/his-CD40NLSmut, 5 μg) indicated in the figure. After 24 hours, luciferase activity was determined and normalized for transfection efficiency using β-gal activity. The data are representative of 3 independent experiments. The error bars indicate the standard deviation of triplicate samples. (B) LBCL cells (FN) were cotransfected with BLyS-luciferase reporter and the expression vectors for c-Rel (pCMV-c-Rel, 5 μg), p65 (pCMVp65, 5 μg), CD40wt (pcDNA3.1/myc/his-CD40, 5 μg), and CD40NLSmut (pcDNA3.1/myc/his-CD40NLSmut, 5 μg) indicated in the figure. After 24 hours, luciferase activity was determined as described for panel A.