Fig. 4.

Expression of TNF and IFN-γ in non-stimulated and stimulated NK cells of the young, the old aged under 85 and the oldest seniors (aged over 85). Data are presented as means ± SEM and concern expression of the studied proteins in NK cells demonstrated as percentages of cells with expression of a particular protein (%) or mean fluorescence intensity (MFI). The same symbols over bars ^X, ^<, ^T, ^o, ^, ^Δ, ⁺, *, ^#, ^Y denote statistically significant differences between similarly treated NK cells of different age groups (i.e. young vs old; young vs oldest or old vs oldest). Horizontal lines above paired bars denote statistically significant differences between treated and untreated NK cells of the same age group (i.e. non-stimulated vs stimulated with IL-2, LPS or PMA with ionomycin): a Expression of TNF (%): ^, ^< p ≤ 0.001; *, ^Xp < 0.01; ^o,⁺p < 0.05. b Expression of TNF (MFI): ^X, ^#, ^<, ^, ⁺, *, ^Δ, ^Yp < 0.001. c Expression of IFN-γ (%): ^<, ^o p < 0.001; ^Δ, ^X, ^Tp < 0.01;⁺p < 0.05 d Expression of IFN-γ (MFI): ^#, *, ^op ≤ 0.01; ^ p < 0.05