Mutual interplay between IL-17–producing γδT cells and microbiota orchestrates oral mucosal homeostasis

Abstract

Significance Elucidating the mechanisms by which homeostasis is established and maintained in the oral mucosa is important for human health. In this study we investigated the ontogeny and function of gingival γδT cells. The majority of these cells originate from embryonic precursors that maintain themselves locally independent of circulating γδT cells arising from adult precursors. The oral microbiota regulates the development of γδT cells, particularly those of embryonic origin. γδT cells represent the major sources of IL-17–producing cells in the gingiva, and they play a critical role in down-modulating gingival steady-state immunity that subsequently shapes oral microbial diversity. This suggests that oral homeostasis requires mutual interactions between γδT cells and the microbiota.