Ectopic PKB activation increases costimulatory molecule expression by pDCs. CD34⁺ HPCs, retrovirally transduced with myrPKB or a control vector, were differentiated toward pDCs in 2 weeks. Cells were either left unstimulated, or CpG-A or Lox was added during the last 18 hours of culture. Expression of HLA-DR, CD40, and CD86 by eGFP⁺CD123⁺BDCA-2⁺BDCA-4⁺ pDCs was determined. Specific staining was calculated by subtracting the mean fluorescence intensity (MFI) of the isotype control from the MFI measured for each marker (n = 3). (A) Representative FACS plots gated on eGFP⁺ pDCs are shown. Numbers in the FACS plots indicate the specific staining calculated for the experiment shown. (B) Mean ± SEM specific staining of eGFP⁺ pDC is shown. *P < .05, paired Student t test.