The gastrointestinal epithelium, which is covered by a single layer of epithelial cells,
including enterocytes, intraepithelial lymphocytes, goblet cells, microfold cells, and dendritic
cells, serves as a protective barrier separating luminal contents from the underlying tissue
compartments. The epithelium plays an important role in the first line of host defense against
a variety of pathogens, as well as maintaining the homeostasis in gastrointestinal tract. All
these epithelial cells express junction complex proteins and form cell junctions such as …