摘要: Tight junctions are cellular structures present in epithelial, endothelial and mesothelial cells (1, 2, 3). They located at the apicolateral part of cell membrane regulate paracellular permeability layers which is called gate function (4). also have a fence segregating apical region from lateral parts preventing proteins area mixing up with those regions (1,4). take determination polarity prevent pathogens invading into subepithelial tissues thus can be considered to represent one innate immune system (5).