Lymphotoxin-Mediated Regulation of γδ Cell Differentiation by αß T Cell Progenitors

Abstract

The thymus gives rise to two T cell lineages, αβ and γδ, that are thought to develop independently of one another. Hence, double positive (DP) thymocytes expressing CD4 and CD8 coreceptors are usually viewed simply as progenitors of CD4 + and CD8 + αβ T cells. Instead we report that DP cells regulate the differentiation of early thymocyte progenitors and γδ cells, by a mechanism dependent on the transcription factor RORgt, and the lymphotoxin (LT) β receptor (LTβR). This finding provokes a revised view of the thymus, in which lymphoid tissue induction-type processes coordinate the developmental and functional integration of the two T cell lineages.