γδTCR-independent origin of neonatal γδ T cells prewired for IL-17 production

A classical view of T cell lineages consists of two major clades of T cells expressing either the alpha beta or gamma delta T cell receptor (TCR). However, genome-wide assessments indicate molecular clusters segregating T cell subsets that are preprogrammed for effector function (innate) from those that mediate conventional adaptive response, regardless of the TCR types. Within this paradigm, gamma delta T cells remain the prototypic innate-like lymphocytes, many subsets of which are programmed during intrathymic development for committed peripheral tissue localization and effector responses. Emerging evidence for innate gamma delta T cell lineage choice dictated by developmental gene programs rather than the sensory TCR is discussed in this review.