Activation of MAP-kinases and NFκB in wt CD40^+/+ and CD40/LMP1⁺//CD40^−/− B cells. Immunoblotting for the activation of the MAPKs and NFκB after stimulation with agonistic anti-CD40 antibody. Splenic B cells were isolated by CD43 depletion and stimulated with anti-CD40 for the indicated times. Whole-cell lysates were separated by SDS-PAGE and immunoblotted with the indicated antibodies. Ponceau-S staining is shown as a loading control.