Fig. 4.

MICA silencing in vascular ECs impairs NK cell degranulation and IFNγ production. Primary cultures of ECs were mock transfected or transfected with either nontargeting (scramble) or MICA-targeting siRNAs. Twenty-four hours post-transfection, ECs were incubated with freshly isolated and purified NK cells at E:T ratio 20:1 for 6 h. Immunostaining for CD107a and intracellular IFNγ were performed as described in Materials and Methods. Untreated NK cells and NK cells stimulated with PMA and ionomycin were used as negative and positive controls, respectively. The percentages of positive cells are indicated. Results are representative of 3 independent experiments.