Fig. 6: B3galt5 deficiency disrupts mucus O-glycosylation and increases permeability of the intestinal barrier.

a The concentration of FITC-dextran in serum of WT and B3galt5 KO mice fed with CD or HFD for 12 weeks (n = 7 for CD, n = 5 for HFD). b Aician blue staining (top) and immunofluorescence staining of Muc2 (bottom) of colon in WT and B3galt5 KO mice fed with 12-week HFD. Quantification of mucus layer thickness (right; n = 12 for WT, n = 14 for KO). Scale bar: 50 μm. c Western blot analysis of Muc2 in intestinal mucus layer of WT and B3galt5 KO mice. d PAS staining of mucin treated with pronase in WT and B3galt5 KO mice. e PAS staining of mucin treated with OgpA and StcE in WT and B3galt5 KO mice. f Negative-ion mode capillary-LC/MS base peak chromatograms of O-glycan alditols of colonic mucin extracted from WT and B3galt5 KO mice. g The concentration of endotoxin in portal vein serum of WT and B3galt5 KO mice (n = 8 per group). h The mRNA expression of inflammation-related gene Mcp-1, Tnf-α and Il-1β in intestine of WT and B3galt5 KO mice fed with 12-week HFD (n = 8 for WT, n = 6 for KO). i Aician blue and Muc2 immunofluorescence staining of colon in WT mice fed with HFD supplemented with TBC 0.05% (w/w) for 12 weeks. Quantification of mucus layer thickness (right; n = 13 for Veh, n = 15 for TBC). Scale bar: 50 μm. CD chow diet, HFD high-fat diet, WT wild type, KO B3galt5 whole-body knockout, OgpA O-glycoprotease, StcE the secreted protease of C1 esterase inhibitor. Data are mean ± SEM. Significance was determined using unpaired two-tailed Student’s t test. Source data are provided as a Source Data file.