Reduced activity of canonical and noncanonical NF-κB components in the splenic and BM B cells of KA/KA mice. (A) Western blot showing the indicated protein levels in splenic cells. B220-enrich indicates column-purified B220⁺ cells; B220-flow, non-B cells that passed through the column; splenocytes, total cell lysate from whole spleen; β-actin, protein-loading control. (B-C) p65 (RelA), RelB, p100/52, and p105/p50 expression levels in nuclear and cytoplasmic fractions of spleen and BM B220⁺ cells of WT (+/+) and KA/KA mice. Lamin B and sp1 were used as controls for the purity of nuclear extracts.