Fig. 6. Epithelial GPR35 protects against Citrobacter rodentium infection.

C. rodentium CFU/g of (a) feces, (b) MLN and liver from Gpr35^f/fVil⁺ (n = 10) and Gpr35^wt co-housed littermates (n = 7). Mice were sacrificed at day 21 p.i. c IgG serum levels in Gpr35^f/fVil⁺ and Gpr35^wt co-housed littermates on day 21 p.i. d Representative AB/PAS staining of proximal colon sections obtained from Gpr35^f/fVil⁺ and Gpr35^wt co-housed littermates on day 21 p.i. Scale bars, 50 μm. e Cell count of goblet cells in (d) performed blindly by two different investigators in at least 30 crypts. f Representative images of proximal colon sections obtained from Gpr35^f/fVil⁺ and Gpr35^wt co-housed littermates on day 21 p.i and stained for Muc2 protein by immunohistochemistry. Scale bars, 50 μm. g mRNA expression levels of Muc2 measured by qRT-PCR in proximal colon samples obtained from Gpr35^f/fVil⁺ and Gpr35^wt co-housed littermates on day 21 p.i. h Representative AB/PAS staining of proximal colon sections obtained from Gpr35^f/fVil⁺ and Gpr35^wt co-housed littermates infected with C. rodentium. Mice were sacrificed at day 9 p.i. Scale bars, 50 μm. i Cell count of goblet cells in (h) performed blindly by two different investigators in at least 30 crypts. J Representative images of proximal colon sections obtained from Gpr35^f/fVil⁺ and Gpr35^wt co-housed littermates on day 9 p.i. and stained for Muc2 protein by immunohistochemistry. Scale bars, 50 μm. k Visualization of bacteria in relation to the epithelium via 16S rRNA fluorescence in situ hybridization (pink) in proximal colon sections obtained from Gpr35^f/fVil⁺ and Gpr35^wt co-housed littermates on day 9 p.i. Each dot represents one animal with medians. Data represent two independent experiments combined. Data are represented as mean ± SEM *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, ****p ≤ 0.0001 by two-way ANOVA with Tukey’s multiple comparisons test in (a) or unpaired student’s t test in (b), (e), (g) and (i).