Fig. 1

TRPM2 and CD38 surface expression on CD56^BrightCD16^Dim/− and CD56^DimCD16⁺ NK cell subsets between groups post IL-2 stimulation. At baseline, TRPM2 surface expression was significantly higher in the ME/CFS group compared to HCs on CD56^BrightCD16^Dim/− (a) and CD56^DimCD16⁺ NK cells (b). A consistent finding was found at dual expression with CD38 on both NK cell subsets (c, d). Post IL-2 stimulation, TRPM2 with and without CD38 significantly decreased on the CD56^DimCD16⁺ subset within the ME/CFS group (b, d). No significant differences in TRPM2 and CD38 surface expression were found within the HC group pre and post IL-2 stimulation in either NK cell subset