Fig. 5

Impact of E. coli and C. amalonaticus on intestinal maturation and colonization resistance. A Course of C. rodentium infection in indicated mice. B In vitro growth inhibition of C. rodentium in the presence of indicated bacteria. Data are shown as fold change compared to C. rodentium O/N culture control. C Expression of ICAM1⁺, CD146⁺, and MadCAM1⁺ on colonic endothelial cells. D Relative abundance (RA) of colonic LP CD45⁻ CD31⁺ endothelial cells in colonized mice. E Representative quantification of vascularization in stained whole-mount tissues in indicated mice. Partial vascularized crypts were quantified by insertion of contour surface modules (gray areas). F Intravital, multiphoton microscopy of small intestinal blood capillaries after i.v. injection of Qtracker™ 655. Vessel areas were quantified with trace image processing to make morphometric measurements within a bounding box (BB). Scale bar: 30 μm. Results are representative of 4–5 experiments. G C. rodentium carriers were cohoused with OMM¹² on day 22 p.i. All mice were gavaged 10 days later with MC² bacteria. CFUs of C. rodentium were determined in feces. H Fecal colonies of E.coli, E.faecalis (from OMM¹²) and C.amalonaticus on Columbia blood agar universal plate from mice of experiment (G) after pathogen elimination. Animals were orally infected with (10⁹ CFU/ml) C. rodentium. Data shown are mean ± SD of 2–3 independent experiments; each symbol represents the value for one mouse (D–F). Dotted line represents the reference range for OMM¹² + MC² mice (D–F). One-way ANOVA was used: ****p < 0.0001; **p ≤ 0.01; *p ≤ 0.05; ns, not significant