Fig. 6: ILA affects human immune responses via AhR and HCA3.
a, Fold change in IL-22 production in purified human CD4+ T cells cultured for 3 d under TH17-polarizing conditions in the presence of ILA at 5, 50 and 200 µM as compared to vehicle (DMSO control). ILA5µm versus vehicle, P = 0.54; ILA50µm versus vehicle, P = 0.031; ILA200µm versus vehicle, P = 0.0098. b, Fold changes over vehicle (DMSO control) in IL-22 production in human purified CD4+ T cells cultured under TH17-polarizing conditions in the presence of 200 µM ILA with and without the AhR antagonist CH-223191. ILA200µm versus ILA200µm + AhRant, P = 0.0005. c, Fold change in IL-12p70 production in purified human monocytes stimulated with LPS and IFN-γ in the presence of ILA at 5, 50 and 200 µM as compared to vehicle (DMSO control). ILA5µm versus vehicle, P = 0.27; ILA50µm versus vehicle, P = 0.041; ILA200µm versus vehicle, P = 0.031. d, Fold changes over vehicle (DMSO control) in IL-12p70 production in purified human monocytes stimulated with LPS and IFN-γ in the presence of 200 µM ILA with and without the AhR antagonist CH-223191. ILA200µm versus ILA200µm + AhRant, P = 0.033. e, Fold changes over vehicle (DMSO control) in IL-12p70 production in purified human monocytes stimulated with LPS and IFN-γ in the presence of 200 µM ILA and ScrRNA or HCA3 siRNA. ILA200µm + ScrRNA versus ILA200µm + HCA3 siRNA, P = 0.027. For all panels, bars show mean ± s.d.. Each dot represents data from an individual donor (n = 4–6), and, for both T cells and monocytes, the measurements are derived from two-to-three independent experiments. Statistical significance was evaluated by two-sided paired (a and c) or two-sided unpaired (b, d and e) t-tests (with Welch’s correction for b and asterisks indicating *P < 0.05, **P < 0.01, ***P < 0.001. For a and c, the absolute cytokine values were compared between ILA- versus vehicle-treated cells. For b, d and e, the fold changes over vehicle (ratios) were compared between ILA- and ILA + antagonist/siRNA-treated cells. Dashed lines indicate a fold change over vehicle of 1.
