Chemokine receptor expression on pbNK cells cocultured with ST decidual cells. pbNK cells from first-trimester pregnant women were cocultured with ST cells grown in the presence of progesterone (100 nM) (C) or with control medium (B) for 36 hours at 37°C. After incubation, chemokine receptor expression on gated CD56⁺CD3⁻ NK cells was analyzed. Control represents staining with FITC-conjugated GAM or GARB Abs. (A) Staining for the chemokine receptor expression on NK cells at the start of the experiment. Data are representative of 4 independent experiments. Percentages of total cells within the quadrant and the mean fluorescent intensity (m) are shown on the plots.