Figure 3.

The cytoprotective effect of B. breve is not mediated by the TNF-α signalling pathway. C57 BL/6 mice were gavaged with PBS or B. breve and challenged with PBS or LPS for 1.5 h. Columns show TNF-α levels (via ELISA) in (a) whole small intestine intestinal homogenates or (b) plasma ± s.d. (c) Representative immunohistochemical staining for F4/80⁺ macrophages (brown cells) in control or B. breve-colonized mice. (d) Western blot analysis (F4/80 or housekeeping β-actin) of whole small intestinal homogenates, with (e) columns show relative density of F4/80 from (from d) whole intestinal homogenates. (f) Columns show F4/80 expression via RT-PCR ± SD. (g) Representative histology image of epithelial cell stripping protocol (modified Weiser method) leaving lamina propria intact (as indicated by arrows) and (h) FACS analysis for purity (anti-CD45). (i) Columns shown TNF-R1 expression via RT-PCR ± SD and (j) western blotting for protein expression in isolated intestinal epithelial cells, with (k) columns showing relative density of TNF-R1 (from (j)). n = 9 mice per group, representative of three experiments analysed with ANOVA Kruskal–Wallis test with Dunn's multiple comparison test (a), and with Mann–Whitney U-test (b,e,f,i,k).