Impact of PepT1 deletion on microbiota composition and colitis requires multiple generations

摘要

Colon tissues and feces were collected from 6-month-old PepT1−/− and WT mice. a Representative images of confocal microscopy analyses of microbiota localization in Carnoy-fixed colonic tissues of WT and PepT1−/− mice, showing mucus thickness (upper right) and distance of the closest bacteria to the intestinal epithelium (lower right) per genotype across five high-powered fields. Green, Muc2; purple, actin; red, bacteria; blue, DNA. Scale bar: 10 μm. b PCR-based quantification of bacterial load in feces (upper) and adhered to the mucosa (lower). c–e Total RNA was extracted from colons, and the expression levels of Zg16 (c), Lyz1 (d) and Defb1 (e) were quantified by qPCR and normalized to those of 36B4. f Enzymatic activity of lysozyme against peptidoglycan in feces supernatants. Data are presented as the mean ± SEM. Significance was determined by unpaired two-tailed student’s t-test (n = 5–6 mice/group; *P < 0.05, n.s. non-significant).