Tight junctions are specialized connections between epithelial or endothelial cells that form a barrier to regulate the passage of ions and solutes between cells. They play a critical role in maintaining the integrity and function of epithelial barriers in various tissues, including the blood-brain barrier and the intestinal barrier. Research in the area of tight junctions focuses on understanding their structure, function, regulation, and contribution to various diseases and conditions, such as inflammatory bowel disease, cancer metastasis, and neurological disorders. This research aims to identify potential therapeutic targets for modulating tight junction function and improve our understanding of their role in maintaining tissue homeostasis.