eLife Assessment
Weiss et al. provide important new insights and convincing evidence to further our mechanistic understanding of how antigen presentation shapes skin persistence of CD8+ TRM. Using a mouse model for inducible genetic ablation of transforming growth factor beta receptor 3 (TGFBR3) in CD8+ T cells, they demonstrate TGFBR3's role in regulating CD8+ TRM persistence in skin. Furthermore, they show that the strength of T cell receptor (TCR) engagement upon initial CD8+ TRM skin seeding has a positive influence on subsequent TRM expansion following a secondary antigen-reencounter. Together, these mechanisms add to our understanding of how the skin CD8+ T cell repertoire is dynamically responsive to topical antigen.