A, Splenic B cells, pDCs and cDCs isolated from BALB/c mice were stimulated with medium (med), CpG-A DNA, CpG-B DNA, non-CpG DNA, or PMA for 45 min. B, Human PBMCs were stimulated with medium, PMA, CpG-B DNA, nCpG, E. coli DNA (EC), EC plus DNase I, or calf thymus DNA (CT) for 45 min. Activation status of PKDs was detected by phospho-specific Western blot assay.