biostudies-literatureUnknown9(1)Durand ADespite being implicated in non-lymphoid tissues, non-recirculating T cells may also exist in secondary lymphoid organs (SLO). However, a detailed characterization of this lymphoid-resident T cell pool has not yet been done. Here we show that a substantial proportion of CD4 regulatory (Treg) and memory (Tmem) cells establish long-term residence in the SLOs of specific pathogen-free mice. Of these SLOs, only T cell residence within Peyer's patches is affected by microbiota. Resident CD4 Treg and CD4 Tmem cells from lymph nodes and non-lymphoid tissues share many phenotypic and functional characteristics. The percentage of resident T cells in SLOs increases considerably with age, with S1PR1 downregulation possibly contributing to this altered homeostasis. Our results thus show that T cell reNature communications68https://www.ebi.ac.uk/biostudies/studies/S-EPMC5754350biostudies-literatureProfiling the lymphoid-resident T cell pool reveals modulation by age and microbiota.PMC5754350Bonilla NGuichard VMattiuz RDurand AAudemard-Verger ARiviere MMartin BLucas BDelon JDelpoux AHamon PBoissonnas AAuffray CfalseProfiling the lymphoid-resident T cell pool reveals modulation by age and microbiota.Despite being implicated in non-lymphoid tissues, non-recirculating T cells may also exist in secondary lymphoid organs (SLO). However, a detailed characterization of this lymphoid-resident T cell pool has not yet been done. Here we show that a substantial proportion of CD4 regulatory (Treg) and memory (Tmem) cells establish long-term residence in the SLOs of specific pathogen-free mice. Of these SLOs, only T cell residence within Peyer's patches is affected by microbiota. Resident CD4 Treg and CD4 Tmem cells from lymph nodes and non-lymphoid tissues share many phenotypic and functional characteristics. The percentage of resident T cells in SLOs increases considerably with age, with S1PR1 downregulation possibly contributing to this altered homeostasis. Our results thus show that T cell re2018-01-01T00:00:00Z2018 Jan2026-05-02T17:42:34.243Z2025-06-01T12:02:45.513ZS-EPMC57543502930203410.1038/s41467-017-02458-4