IL-2 dependent induction of NK cell apoptosis by <i>M. bovis</i> BCG.

<p>A) Representative FACS dot-plot of purified NK cells co-cultured or not with <i>M. bovis</i> BCG (MOI 1:5) and IL-2 (100U/ml) for 4 days before BrdU incorporation, antibody detection and 7AAD staining (One of three technical replicates). B) Bar graph showing on the left, the frequency of replicating events (BrdU⁺/7AAD⁺) and, on the right, the frequency of apoptotic events (BrdU^-/7AAD^low) of NK cells from one donor exposed or not to mycobacteria and IL-2 (Mean +/- SD of technical triplicates, unpaired t test, *** p<0.001). C) Frequencies of early (PI⁺/Annex V^-) versus late apoptotic events (PI⁺/Annex V⁺) over the time of purified NK cells cultured or not with <i>M. bovis</i> BCG (MOI 1:1) and IL-2 (100U/ml). D) Bar graph summarizing frequencies of apoptotic events after 48h of culture with or without mycobacteria and IL-2 from independent experiments and donors (n=3, paired t test, *p<0.05).