Fig. 6

A. Baseline NK cell cytotoxicity. B. Enhanced NK cell cytotoxicity following overnight IL-2 stimulation compared with baseline. Bar graphs represent percentage of K562 cell death for all effector:target ratios; 12.5:1 and 6.25:1. Data presented as mean ± SEM and *p < 0.05; ***p < 0.0001. HC, healthy controls; ME/CFS, Myalgic encephalomyelitis/chronic fatigue syndrome; IL-2, interleukin-2