Fig. 3.

Reduced expression of IL-12Rβ2 and phosphorylation of STAT4 on/in CD56^bright NK cells in systemic inflammation. PBMC from patients and from healthy control subjects (group 1; n = 10) were stimulated with inactivated S. aureus in the presence of autologous serum (a, b, d–f) or FCS (c). (a) Representative dot plots for staining of IL-12Rβ2 on CD56^bright NK cells from a control subject and a patient 1 d after injury. Numbers indicate the percentage of positive cells. (b) Cumulative data of the percentage of IL-12Rβ2⁺ CD56^bright NK cells in the presence of autologous serum. Note, due to insufficient cell numbers only n = 8–9 values were available for d1 and d8. (c) Percentage of IL-12Rβ2⁺ CD56^bright NK cells in the presence of FCS (n = 8 on d8). (d) Representative histograms showing the phosphorylated STAT4 (pSTAT4) expression of unstimulated (none) and stimulated cells from one control subject and one patient on day 1 after injury. ΔMFI depicts the difference between the mean fluorescence intensity (MFI) of stimulated and unstimulated cells. (e) Cumulative data of the ΔMFI of CD56^bright NK cells from controls and patients 1 or 8 d after injury (each n = 8) or at the day of discharge presented as Tukey box plots. Horizontal lines indicate the median and interquartile range. (f) Spearman correlation between the percentage of IL-12Rβ2⁺ cells (obtained from Fig. 3b) and ΔMFI pSTAT4 (obtained from Fig. 3e). Statistical analyses were performed using the Mann Whitney U test. #, p < 0.05; ##, p < 0.01; ###, p < 0.001 versus controls. c, control subjects; D, day of discharge; iso, isotype control.