Fig. 4
Inflammatory licensing of rMAPC leads to enhanced T-cell suppression. a Co-cultures of T cells with rMAPC in the presence of MBP, where rMAPC were either pre-treated or not (white bars) with different combinations of pro-inflammatory cytokines (IFNγ + TNFα, IFNγ + IL1β, TNFα + IL1β). Negative control (T cells without MBP) is shown as a dotted line. Asterisks indicate statistical significance compared to the positive control (1:0, T cells + MBP). Paragraph signs (§) indicate the statistical significance between the pre-treated (assigned bars) and non-treated (white bars) corresponding ratios. b Application of inhibitors in the co-culture (1:0.5 ratio) after IFNγ + TNFα pre-treatment (black bars). Significant differences compared to the positive control (1:0, T cells + MBP) are shown with asterisks. Paragraph signs (§) show differences with the non-pre-treated 1:0.5 ratio (white bar). c Application of inhibitors in the co-culture (1:0.5 ratio) after TNFα + IL1β pre-treatment (striped bars). Significant differences compared to the positive control (1:0, T cells + MBP) are shown with asterisks. Paragraph signs (§) show differences with the non-pre-treated 1:0.5 ratio (white bar). Results are shown as mean percentages ± SEM of proliferation normalized to the positive control (1:0, T cells + MBP), from three independent experiments, with triplicates per experiment. Data were analyzed with non-parametrical Kruskal Wallis multiple group comparison test, followed by Dunns for differences between the groups. *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001; § P ≤ 0.05, §§ P ≤ 0.01, §§§ P ≤ 0.001. 1-Mt-D 1-methyl-dextro-tryptophan, 1-Mt-L 1-methyl-levo-tryptophan, IFN interferon, IL interleukin, L-NMMA L-NG-monomethyl arginine citrate, MBP myelin basic protein, TNF tumor necrosis factor