A pathogenic role for cystic fibrosis transmembrane conductance regulator in celiac disease

A

Immunoblot with anti‐TG2 or anti‐β‐actin as loading control in whole lysates from small intestine homogenates of Cftr ^{F508del/F508del} and wild‐type (Cftr ^WT) mice (n = 5 per group) and densitometric analysis of immunoblots. Mean ± SD of triplicates of independent pooled samples. **P < 0.01 (Student's t‐test).

B

Detection of NLRP3 expression (top) and caspase‐1 cleavage (bottom) by immunoblot of whole lysates from small intestine homogenates of Cftr ^WT and Cftr ^{F508del/F508del} mice (n = 5) and densitometric analysis of immunoblots. Mean ± SD of triplicates of independent pooled samples. **P < 0.01 Cftr ^WT vs. Cftr ^{F508del/F508del} (Student's t‐test).

C

Protein levels of IL‐17A and IFN‐γ from small intestine homogenates of Cftr ^WT and Cftr ^{F508del/F508del} (n = 10). Mean ± SD of triplicates of independent pooled samples. ***P < 0.001 Cftr ^WT vs. Cftr ^{F508del/F508del} (Student's t‐test).

D

IL‐15 mRNA (left) and protein (right) levels in small intestine homogenates from Cftr ^{F508del/F508del}, Cftr ^−/− or their Cftr ^WT littermates (n = 10 per group). Mean ± SD of triplicates of independent pooled samples. **P < 0.01 Cftr ^{F508del/F508del} vs. Cftr ^WT(FVB/129), or °°P < 0.01 Cftr ^−/− vs. Cftr ^WT(B6.129P2) (ANOVA, Bonferroni post hoc test).

E

IL‐15 mRNA levels in small intestine homogenates from Cftr ^WT mice or Cftr ^{F508del/F508del} or TG ^−/−/Cftr ^{F508del/F508del} or TG ^−/− mice (n = 10 per group). Mean ± SD of triplicates of independent pooled samples. ***P < 0.001 vs. Cftr ^WT, °°P < 0.01, ^## P < 0.01 vs. Cftr ^{F508del/F508del} (ANOVA, Bonferroni post hoc test).

F

Effects of 4 weeks of oral administration of gliadin on IL‐15, IL‐17A, and IFN‐γ protein levels in small intestine homogenates from Cftr ^{F508del/F508del} and Cftr ^WT mice (n = 10 mice per group of treatment). Mean ± SD of triplicates of independent pooled samples. **P < 0.01, ***P < 0.001 (Cftr ^{F508del/F508del} vs. Cftr ^WT mice prior gliadin challenge), °°°P < 0.001 (Cftr ^{F508del/F508del} mice vs. Cftr ^{F508del/F508del} mice after gliadin challenge; ANOVA, Bonferroni post hoc test).

G–I

BALB/c mice (G) fed with a gluten‐free diet for at least three generations, or (H) NOD or (I) NOD‐DQ8 mice orally challenged with vehicle or gliadin for 4 weeks (5 mg/daily for 1 week and then 5 mg/daily thrice a week for 3 weeks). Representative traces of CFTR‐dependent Cl⁻ secretion measured by forskolin (Fsk)‐induced increase in chloride current [Isc (μA/cm²)] in small intestines mounted in Ussing chambers; quantification of the peak CFTR inhibitor 172 (CFTRinh₁₇₂)‐sensitive Isc (∆Isc) in tissue samples (n = 3 independent experiments). Mean ± SD of samples assayed; **P < 0.01, ***P < 0.001 vs. challenged with gliadin (Student's t‐test).

Figure 1. CFTR malfunction favors gliadin responsiveness in vivo .