Figure 7: Stimulation of DCs and monocytes.

(a) In stimulation assay, bacteria were fixed with 0.5% paraformaldehyde in PBS, washed and co-cultured at a ratio of 100:1 with mouse mesenteric CD11c⁺ DCs. Ec, E. coli EHV2; Bt, B. thetaiotaomicron. Cell surface expression of CD86, CD40 and MHC-II was analysed by flow cytometry. (b) Human monocytic THP-1 cells were stimulated with fixed bacteria at ratios of 5:1 and 1:1 to cells for 14 h at 37 °C. Cell surface expression of CD54 was analysed by flow cytometry. In (a,b), data are shown as mean fluorescence intensity, MFI±s.e.m. from three independent experiments. N=6, *P<0.05 (ANOVA, Bonferroni’s multiple comparison test). (c) Cytokine expression in the culture supernatant of stimulated mesenteric CD11c⁺ DCs stimulated for 14 h at 37 °C with fixed Ec, Bt and 500 ng ml⁻¹ of LPS. PBS was used as negative stimulation control. Data are shown as mean±s.e.m. from two independent experiments. N=4–5, *P<0.05 (ANOVA, Bonferroni’s multiple comparison test).