Figure 3.

Stimulated CD56^bright NK cells express increased levels of CD117 after trauma that inversely correlates with IFN-γ synthesis and IL-12Rβ2 expression. PBMC from control subjects (c) or patients (t) were stimulated with S. aureus and the expression of CD117, IFN-γ, and the IL-12Rβ2 chain was examined. Unstimulated cells (none) served as control. (A) Representative contour plots of the expression of CD117 and IL-12Rβ2 on gated CD3⁻CD56^bright NK cells. Numbers indicate the percentage of CD117⁺ among IL-12Rβ2⁻ cells (rectangle). (B) Cumulative data of the percentage of CD117⁺ cells among IL-12Rβ2⁻ cells (n = 12). (C,D) Spearman correlation of CD117 expression with IFN-γ synthesis (C) and IL-12Rβ2 expression (D) on CD3⁻CD56^bright NK cells. (E–G) Recombinant IL-15 or SB431542 (inhibitor of the TGF-βRI) was added during stimulation of PBMC from trauma patients with S. aureus [the values for cells stimulated with S. aureus alone are also shown in Figures 1B,C and (B)]. (E) Percentage of CD117⁺ cells among IL-12Rβ2⁻CD3⁻CD56^bright NK cells (n = 11–12). (F) Expression of the IL-12Rβ2 chain on CD3⁻CD56^bright NK cells (n = 11–12). (G) Expression of IFN-γ in CD3⁻CD56^bright NK cells (n = 12–13). Horizontal lines indicate the median/interquartile range. Statistical differences between control and trauma (B) were tested using the Mann-Whitney U-test, differences between different culture conditions (E–G) were tested using the Wilcoxon signed rank test. *p < 0.05; **p < 0.01; and ***p < 0.001.