title: Regulatory T cell plasticity: beyond the controversies.
abstract: Forkhead box P3 (Foxp3)(+) regulatory T (Treg) cells represent a distinct cell lineage that is committed to suppressive functions, whose stable differentiation state ensures the robustness of self-tolerance and immune homeostasis in a changing environment. Recent studies have challenged this notion and suggest that Treg cells retain developmental plasticity to be reprogrammed to Foxp3(-) helper T cells in response to extrinsic perturbations such as inflammation and lymphopenia. This issue of Treg cell plasticity, however, remains controversial because other recent reports argue against the plasticity phenomena. Here, I propose that the controversies can be resolved by considering the heterogeneity model of plasticity, which hypothesizes that the observed plasticity does not reflect lineage reprogramming of Treg cells but rather a minor population of uncommitted Foxp3(+) T cells.
authors.affiliation: Research Unit for Immune Homeostasis, RIKEN Research Center for Allergy and Immunology, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan. shohei@rcai.riken.jp
authors.forename: Shohei
authors.initials: S
authors.lastname: Hori
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D019070:Cell Lineage; D051858:Forkhead Transcription Factors / Q000276:immunology; D006801:Humans; D050378:T-Lymphocytes, Regulatory / Q000166:cytology* / Q000276:immunology*
chemical_list: D051858:Forkhead Transcription Factors