Figure 7.

Restoration of the mucus layer in the colon by antibiotic withdrawal. The two-layer structure and the thickness of the inner mucus layer (bracket symbols) returned to control levels [see controls in Figure 3] for all groups of antibiotic-treated mice after 7 days of antibiotic withdrawal. No significant difference was found among treatment groups and controls. Intact bacteria (arrows) recolonized the outer mucus layer. LR group, MR group, and HR group represent the 7-day low, medium, and high-dose antibiotic treatments plus a 7-day recovery, respectively. E: Epithelium