MODULATION OF EPITHELIAL-CELL GROWTH BY INTRAEPITHELIAL GAMMA-DELTA T-CELLS

The role played in immune surveillance by gamma delta T cells residing in various epithelia has not been clear. It is shown here that activa ted gamma delta T cells obtained from skin and intestine express the e pithelial cell mitogen keratinocyte growth factor (KGF). In contrast, intraepithelial alpha beta T cells, as well as all lymphoid alpha beta and gamma delta T cell populations tested, did not produce KGF or pro mote the growth of cultured epithelial cells. These results suggest th at intraepithelial gamma delta T cells function in surveillance and in repair of damaged epithelial tissues.