Fig. 6

Treatment with a mixture of seven short-chain fatty acid-producing bacterial strains (7-mix) and the resulting culture supernatant mixture (mix-sup) induces M2 macrophage polarization, reducing ulcerative colitis and improving gut barrier function in macrophage-depleted mice. A. qRT-PCR analysis of the effect of 7-mix and mix-sup on the mRNA expression of cytokines produced by M1 and M2 macrophages. B. Flow cytometry analysis of the effect of 7-mix and mix-sup on macrophage polarization. C. RAW264.7 cells co-cultured with 7-mix and mix-sup. D. 7-mix and mix-sup induced M2 macrophage polarization. E. Caco-2/RAW264.7 and NCM460/RAW264.7 transwell co-culture system. F. qRT-PCR analysis of the effect of macrophage treatment with 7-mix or mix-sup on the mRNA expression of TNF-α, IL-6, occludin and ZO-1 in Caco-2 and NCM460 cells. N = 3–4. *P < 0.05, **P < 0.01, ***P < 0.001