Blood-thirsty: S1PR5 and TRM

Abstract
In this elegant study, Evrard et al. (2021. J. Exp. Med. https://doi.org/10.1084/jem.20210116) find that sphingosine 1-phosphate receptor 5 (S1PR5) powerfully impairs tissue-resident memory T cell (T-RM) formation, and that tissue-derived TGF-beta limits S1pr5 expression by infiltrating T cells.