Fig. 1

Measurement of the ERK1/2 in CD56^dimCD16⁺ NK cells. For a representative individual, CD56^dimCD16⁺ NK cells were identified according to the surface expression of CD56 and CD16 (a) which was extrapolated onto a histogram plot to identify median fluorescence intensity (MFI) of ERK1/2 in US, K562 and PMA/I stimulated cells (b). Compared to the NFC, phosphorylated ERK1/2 in CD56^dimCD16⁺ NK cells from CFS/ME patients was significantly reduced (c, *p < 0.05). Data are presented as MFI with interquartile range