Induction of cell surface antigen expression after DC CD2 engagement. The pDCs were isolated and cultured for 24 hours in the presence of either IR control or the anti-T11_2/3 mAb pair (A-B), or else anti-T11_1/2, -T11_2/3, or -T11_1/3 mAb pairs (C). Quadrant boundaries were set using isotype control. Percentages indicate the percentage of cells within the gated region. Cultures were harvested, stained, and analyzed by flow cytometry; the data shown are similar to those of 3 other experiments. Values in parentheses indicate the MFI of the high and low populations. Closed histograms indicate CCR7 expression on pDCs cultured with IR, and open histograms indicate CCR7 expression on pDCs cultured with mAb pairs.