Fig. 8.

Defective killing is associated with sustained Ca²⁺ flux. NK cells were pretreated for 2 h with 50 nM CMA or DMSO as a control and loaded with the calcium binding dye Fluo-8. Cells were allowed to form conjugates with K562 target cells for 30 min. Samples were subsequently diluted and agitated to prevent the formation of new conjugates. a The Ca²⁺ flux in NK cells in conjugates was analyzed over 90 min by flow cytometry. The Ca²⁺ level was plotted against time, and a regression line was calculated. b Slope of the regression line for the calcium signal over time in DMSO- and CMA-treated NK cells for three independent experiments using NK cells from different donors (*p < 0.05)