Epithelial TNF controls cell differentiation and CFTR activity to maintain intestinal mucin homeostasis
Efren A. Reyes, … , Zev J. Gartner, Ophir D. Klein
Efren A. Reyes, … , Zev J. Gartner, Ophir D. Klein
Published August 29, 2023
Citation Information: J Clin Invest. 2023;133(20):e163591. https://doi.org/10.1172/JCI163591.
View: Text | PDF
Research Article Gastroenterology Article has an altmetric score of 26

Epithelial TNF controls cell differentiation and CFTR activity to maintain intestinal mucin homeostasis

Abstract

The gastrointestinal tract relies on the production, maturation, and transit of mucin to protect against pathogens and to lubricate the epithelial lining. Although the molecular and cellular mechanisms that regulate mucin production and movement are beginning to be understood, the upstream epithelial signals that contribute to mucin regulation remain unclear. Here, we report that the inflammatory cytokine tumor necrosis factor (TNF), generated by the epithelium, contributes to mucin homeostasis by regulating both cell differentiation and cystic fibrosis transmembrane conductance regulator (CFTR) activity. We used genetic mouse models and noninflamed samples from patients with inflammatory bowel disease (IBD) undergoing anti-TNF therapy to assess the effect of in vivo perturbation of TNF. We found that inhibition of epithelial TNF promotes the differentiation of secretory progenitor cells into mucus-producing goblet cells. Furthermore, TNF treatment and CFTR inhibition in intestinal organoids demonstrated that TNF promotes ion transport and luminal flow via CFTR. The absence of TNF led to slower gut transit times, which we propose results from increased mucus accumulation coupled with decreased luminal fluid pumping. These findings point to a TNF/CFTR signaling axis in the adult intestine and identify epithelial cell–derived TNF as an upstream regulator of mucin homeostasis.

Authors

Efren A. Reyes, David Castillo-Azofeifa, Jérémie Rispal, Tomas Wald, Rachel K. Zwick, Brisa Palikuqi, Angela Mujukian, Shervin Rabizadeh, Alexander R. Gupta, James M. Gardner, Dario Boffelli, Zev J. Gartner, Ophir D. Klein

×

Figure 3

TNF does not affect secretory cell turnover, but regulates the proportion of absorptive and secretory progenitors.

Options: View larger image (or click on image) Download as PowerPoint
TNF does not affect secretory cell turnover, but regulates the proportio...
(A) Experimental design. TAM, tamoxifen. (B) Micrograph of AtohCreERT2; Rosa26tdTomato control and Tnf–/– mice induced with tamoxifen at 0 hours to label secretory progenitors, injected with EdU at 24 hours to label proliferating cells, and analyzed at 72 hours. Yellow arrows mark tdTomato+EdU+ cells. Cyan arrows pinpoint the hinge region. (C) Quantification of secretory progenitor daughter cell (tdTomato+EdU+) displacement from the hinge region (n = 6 mice per group, 25 full-profile crypt-villus units per mouse). (D) Micrographs of AtohCreERT2; Rosa26tdTomato control and Tnf–/– mice induced with tamoxifen for 36 hours. White boxes highlight insets. Yellow brackets show the progenitor zone. (E) Representative crypts labeled for both absorptive (NICD+) and secretory (tdTomato+) progenitors. (F) Percentage secretory progenitors and (G) percentage absorptive progenitors were quantified as the number of tdTomato+ or NICD+ cells, respectively, over total progenitors (NICD+ and tdTomato+, shown in H) from the +4 region to the top of the crypt (n = 7 control, 8 Tnf–/– mice, with 20 full-profile crypts per mouse). (I) Representative RNAscope micrograph of Dll1 transcripts in control and Tnf–/– mice. (J) Dll1+ secretory progenitors were quantified by counting high-Dll1-expressing cells (with more than 3 dots per cell) from the +4 region to the top of the crypt (10 crypts per mouse, n = 3 mice per group). (K and L) Crypt length was measured as the distance from the bottom of the crypt to the hinge region. Villus length was measured as the distance from hinge region to villus tip (n = 3 mice per group, at least 30 full-profile crypts were measured per mouse). P values calculated by unpaired, 2-tailed t test (C, F–H, and J–L). Scale bars: 50 μm.