Murine T cells with invariant γδ antigen receptors: Origin, repertoire, and specificity

T cells bearing invariant γδ T cell antigen receptors localize to distinct epithelial sites in the adult mouse. These γδ T cells differ from the lymphoid αβand γδ T cells in several ways. The epithelial γδ T cells appear to be the product of the earliest waves of TCR expressing cells in the fetal thymus. Additionally, the rearranged TCR junctions exhibit a distinct lack of diversity, possibly a result of the fetal origin and a specialized selection process. The use of a single invariant TCR and strict tissue localization suggest that these γδ T cells may provide a specialized function in the epithelial tissues distinct from that of the circulating αβ and γδ T cells.