Both retention and recirculation contribute to long-lived regulatory T-cell accumulation in the thymus.

ABSTRACT: Natural Treg cells acquire their lineage-determining transcription factor Foxp3 during development in the thymus and are important in maintaining immunologic tolerance. Here, we analyzed the composition of the thymic Treg-cell pool using RAG2-GFP/FoxP3-RFP dual reporter mice and found that a population of long-lived GFP(-) Treg cells exists in the thymus. These long-lived Treg cells substantially increased with age, to a point where they represent >90% of the total thymic Treg-cell pool at 6 months of age. In contrast, long-lived conventional T cells remained at ∼ 15% of the total thymic pool at 6 months of age. Consistent with these studies, we noticed that host-derived Treg cells represented a large fraction (∼ 10%) of the total thymic Treg-cell pool in bone marrow chimeras, suggesting t

SUBMITTER: Yang E 

PROVIDER: S-EPMC4177035 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature