Chymase/Mcpt4: A serine protease with a crucial role in the modulation of colonic epithelial cell permeability in colitis

Ulcerative colitis is characterized by impaired gut barrier function. Mast cell-derived chymase influences epithelial integrity, but its primary role remains unclear. Using the TAILS technique, we identified chymase/Mcpt4 substrates in colonic epithelial cells, revealing cytoskeletal and junction-associated proteins enrichment. Transepithelial electrical resistance assays confirmed chymase-mediated barrier disruption using T84 cells. Our data indicates that chymase/Mcpt4 plays a role in epithelial dysfunction in ulcerative colitis, suggesting it as a possible therapeutic target.