CpG down-regulates CD300a and CD300c transcripts in pDCs after CpG treatment. (A) pDCs isolated with the BDCA-4 kit were analyzed for purity by staining with BDCA-2 mAbs. Data were from one representative experiment (n = 10). Numbers on plots are percentages of purified BDCA-4⁺ cells. (B) Isolated pDCs were fixed and permeabilized and further stained intracellularly with TLR9-PE antibody and analyzed by flow cytometry. Data were from 1 of the 4 experiments. (C) pDCs were cultured with CpG ODN or control ODN for 2 and 24 hours; RNA were extracted and subjected to DNA microarray analysis. Normalized relative expression values of CD300a and CD300c mRNA in pDCs are shown (from left to right). Data were from one DNA microarray experiment. (D) Expression of CD300a and CD300c mRNA in pDCs (from left to right) cultured with or without CpG for 2 and 24 hours were analyzed using quantitative real-time PCR. Data were normalized according to level of the housekeeping gene UCE. Error bars represent SEM.