Cytolytic activity against iDCs and induction of DC maturation by IL-2–activated LAD1 NK cells. (A) IL-2–activated NK cell populations derived from the LAD1 patient 1 and from the representative healthy donor 1 were analyzed for cytolytic activity against CD14⁻CD1a⁺ immature monocyte-derived iDCs either in the absence of mAb (white bar) or in the presence of the mAbs specific for the indicated molecules (black bars). The E/T ratio used was 10:1. The results are representative of 3 independent experiments; the standard deviation of the mean of the triplicates was less than 5%. (B) Immature DCs were cocultured for 2 days with NK cell populations derived from either the LAD1 patient or the representative healthy donor. DCs were analyzed by indirect immunofluorescence and cytofluorimetric analysis for expression of the indicated maturation markers. The percent of positive cells is indicated. Negative and positive controls (eg, iDCs cultured in medium alone [CTR] or in the presence of LPS, respectively) are shown.