Activation of STAT6 in Intestinal Epithelial Cells Predisposes to Gut Inflammation

Area of Science:

• Gastroenterology
• Immunology
• Molecular Biology

Background:

• Ulcerative colitis (UC), a form of inflammatory bowel disease (IBD), is linked to Type 2 immune responses.
• The role of signal transducer and activator of transcription (STAT) 6 signaling in intestinal epithelial cells (IECs) during IBD remains unclear.
• STAT6 is a transcription factor involved in immune cell signaling.

Purpose of the Study:

• To investigate the specific contribution of STAT6 activation within IECs to the development and severity of colitis.
• To elucidate the molecular mechanisms by which STAT6 in IECs influences gut inflammation.

Main Methods:

• Utilized a mouse model (VillinCre_STAT6vt) with constitutively active STAT6 specifically in IECs.
• Induced colitis using dextran sodium sulfate (DSS) to mimic UC.
• Performed bulk RNA sequencing on colonic tissue and analyzed gene expression patterns.
• Compared findings with human IBD single-cell RNA sequencing datasets.

Main Results:

• VillinCre_STAT6vt mice exhibited increased pathology and mortality in the DSS-induced colitis model.
• STAT6 activation in IECs led to enhanced and systemic inflammation.
• Differential gene expression in naïve VillinCre_STAT6vt mice revealed STAT6-regulated pathways including unfolded protein response, MTORC, MYC signaling, and protein secretion.
• Overlapping gene expression changes were observed in epithelial and macrophage compartments between the mouse model and human IBD patients.

Conclusions:

• Activation of STAT6 in the intestinal epithelium significantly predisposes to exacerbated colitis.
• STAT6 signaling in IECs plays a critical role in promoting gut inflammation in IBD.
• These findings highlight a potential therapeutic target for managing UC and related inflammatory conditions.