Modulation of Epithelial Cell Growth by Intraepithelial γδ T Cells

The role played in immune surveillance by γδ T cells residing in various epithelia has not been clear. It is shown here that activated γδ T cells obtained from skin and intestine express the epithelial cell mitogen keratinocyte growth factor (KGF). In contrast, intraepithelial αβ T cells, as well as all lymphoid αβ and γδ T cell populations tested, did not produce KGF or promote the growth of cultured epithelial cells. These results suggest that intraepithelial γδ T cells function in surveillance and in repair of damaged epithelial tissues.