NKG2D expression on purified IL-2-stimulated NK cells (100 U/ml for 4 days) exposed to L-MICA-129Met (n = 25) or L-MICA-129Val clones (n = 25) for 0, 4, and 24 h was analyzed by flow cytometry. NK cells (2.5 × 105) were co-cultured with 5 × 104 target cells and analyzed for NKG2D expression after gating of CD3−CD56+ cells. The means and SD of the percentage of NKG2D+ NK cells (left panel) and of the MFI of NKG2D (right panel) are shown. Differences between the groups were analyzed by repeated measures ANOVA, and P-values for pairwise comparisons are indicated. 