Epithelial cells and their neighbors. III. Interactions between intraepithelial lymphocytes and neighboring epithelial cells.

Intraepithelial gammadelta-T cells are present in all epithelial tissues, where they reside in close contact with neighboring epithelial cells. Our data support the idea that the role of these cells is to monitor neighboring cells for signs of damage or disease. Once a problem is detected, the intraepithelial gammadelta-T cells can lyse damaged or malignant epithelial cells, directly participate in tissue repair through production of epithelial growth factors, and play a unique role in the recruitment of inflammatory cells to the site of damage. Intraepithelial gammadelta-T cells play unique roles in homeostasis and disease.