Mucosal Cytokine Expression Associated With Deep Endoscopic Mucosal Healing in Ulcerative Colitis.

Area of Science:

• Gastroenterology
• Immunology
• Molecular Biology

Background:

• Ulcerative colitis (UC) is a chronic inflammatory bowel disease with unknown etiology and no cure.
• Cytokines are implicated in UC pathogenesis, and targeted therapies show promise for refractory cases.
• Identifying mucosal cytokines linked to nonrelapsing mucosal healing (MH) is crucial for treatment development.

Purpose of the Study:

• To quantify mucosal cytokines in UC patients.
• To correlate cytokine expression with endoscopic findings of mucosal healing.
• To identify specific cytokines as potential biomarkers for MH in UC.

Main Methods:

• Prospective observational study of 163 UC patients.
• Endoscopic evaluation using Mayo Endoscopic Subscore (MES) and linked color imaging (LCI).
• Quantification of cytokine mRNA expression via real-time PCR in biopsy tissue, correlated with endoscopic data.

Main Results:

• Elevated levels of IFNγ, IL-1β, IL-8, IL-17A, and IL-23 correlated with endoscopic severity (MES and LCI).
• Distinct cytokine profiles (IL-22, IL-33) were observed between MES and LCI classifications based on disease severity.
• RNA sequencing revealed IL-5 and IL-6 involvement in subtle endoscopic redness differences in patients with MES 0.

Conclusions:

• This study establishes a correlation between mucosal cytokine expression and MH pathogenesis in UC.
• Specific cytokines may serve as valuable molecular markers for MH in UC.
• Findings support targeting specific cytokines for improved therapeutic strategies in UC.