 Epithelial tight junctions, TJs, are important structures that control the movement of substances across cell membranes. They form a physical barrier between two neighboring cells, allowing only certain molecules to pass through while blocking others. When this barrier is disrupted, it can lead to inflammation and other health problems such as inflammatory bowel disease, IBD. Research suggests that TJ disruption may be a cause of IBD, but its exact role in the disease is still unknown. Therapeutic strategies aimed at restoring TJ function could potentially reduce the severity of IBD symptoms. This article was authored by Sung Hee Lee.