Close link between development and function of gamma-delta T cells

Murine ?d T cells develop as the first T-cell lineage within the fetal thymus and disproportionately localize in mucosal tissues such as lung, skin, uterus, and intestine of adult mice. These unique developmental features and distribution patterns of ?d T cells enable rapid functioning against various insults from pathogens. ?d T cells are also able to respond to local inflammation and consequently regulate the pathogenesis of autoimmune disorders and development of tumors in mice and humans. Hence, it is clinically important to understand the mechanisms that regulate ?d T cell functions. Recent evidence has shown that generations of effector ?d T cell subsets producing IFN-?, IL-4, and IL-17 are programmed in the murine thymus before their migration to peripheral tissues. This review outlines our current understanding of the development and function of ?d T cells as they influence both innate and acquired immunity.