Fig. 4

1,25(OH)₂D₃ affects A. muciniphila colonization in gut. a Relative abundance of A. muciniphila in feces and b Relative levels of total bacteria in MLNs from wild type and Cyp27b1^−/− mice with 10–12-week age. c The mucus layer (arrows) from wild type and Cyp27b1^−/− mice with the age of 10–12 weeks assessed on Alcian blue-stained colonic sections. The histogram showing the mean percentage of the mucus layer. Scale bars, 100 μm. d Relative abundance of A. muciniphila in feces from wild type, Cyp27b1^−/− and Cyp27b1^−/− mice feed with 1,25(OH)₂D₃ at the age of 8–10 months. e The mucus layer (arrows) from wild type, Cyp27b1^−/− and Cyp27b1^−/− mice feed with 1,25(OH)₂D₃ on Alcian blue-stained colonic sections. The histogram showing the mean percentage of the mucus layer. Scale bars, 100 μm. f CD3 and F4/80 expression in colon tissues from the wild type and Cyp27b1^−/− mice at the age of 8–10 months by immunohistochemical staining. Magnification, ×400. The histogram showing the mean percentage of the CD3 or F4/80 positive cells from five randomly selected fields. *P < 0.05, **P < 0.01. WT: wild type, KO: Cyp27b1^−/−, KO + VD: Cyp27b1^−/− mice feed with 1,25(OH)₂D₃