Figure 3.

Increase in mitochondrial mass and mitochondrial membrane potential induced by IL-2 is mediated by an increase in PGC-1α expression. Purified human NK cells were transfected with siRNA specific for PGC-1α or negative controls and then treated with 50 (control) or 2000 (activated) IU/mL of IL-2 for 72 h. (a) PGC-1α mRNA expression was determined by qRT-PCR. Relative expression was normalized with control NK cells, and results show the mean of 8 independent experiments ± SE (^∗ p < 0.05). (b) Mitochondrial mass. (c) Mitochondrial membrane potential was analyzed by flow cytometry. Data are shown as the mean of fluorescence intensity in cells and normalized against controls (control siRNA and 50 IU/mL IL-2). Results are mean ± SE from 5 independent experiments (^∗∗ p < 0.01).