Wei et al. used Foxp3-transduced conventional T cells as a gain-of-function probe, and identified an endogenous Foxp3+ subset that acquired Treg-like transcriptional, chromatin, and suppressive features, exclusively in vivo. Endogenous Foxp3 induction in vivo required a permissive environment created by reduced AKT-mTOR signaling and Foxp3 engagement with STAT5 and NF-κB at Foxp3 regulatory elements. Foxp3 drove a stepwise chromatin remodeling program at Foxp3-induced open chromatin regions, establishing NFκB-linked core modules shared across Treg subsets, and effector-specific modules co-regulated with AP-1.
Contributed by Shishir Pant
(1) Wei Y (2) Ago H (3) Murakami R (4) Funatsu S (5) Osaki M (6) Nakajima A (7) Hasegawa Y (8) Kawakami R (9) Sakaguchi S (10) Hori S
Wei et al. used Foxp3-transduced conventional T cells as a gain-of-function probe, and identified an endogenous Foxp3+ subset that acquired Treg-like transcriptional, chromatin, and suppressive features, exclusively in vivo. Endogenous Foxp3 induction in vivo required a permissive environment created by reduced AKT-mTOR signaling and Foxp3 engagement with STAT5 and NF-κB at Foxp3 regulatory elements. Foxp3 drove a stepwise chromatin remodeling program at Foxp3-induced open chromatin regions, establishing NFκB-linked core modules shared across Treg subsets, and effector-specific modules co-regulated with AP-1.
Contributed by Shishir Pant
ABSTRACT: Regulatory T cells (T(reg) cells) express the master regulator, Foxp3, and display distinctive epigenetic landscapes ensuring T(reg) cell-specific gene expression and stable suppressive functions, yet Foxp3's contribution to this epigenetic identity remains unclear. Leveraging Foxp3-transduced conventional T cells as a gain-of-function probe in mice, we identified a previously unrecognized subset that acquires endogenous Foxp3 expression, T(reg) cell-like transcriptomic and chromatin features, and suppressive functions exclusively in vivo. These Foxp3-driven features were conserved in T(reg) cells but impaired in Foxp3-mutant T(reg)-like cells, demonstrating a Foxp3 requirement. Induction of endogenous Foxp3 expression in vivo required reduced AKT-mTOR signaling and Foxp3-dependent engagement of STAT5 and nuclear factor _B (NF-_B). Temporal chromatin profiling revealed stepwise Foxp3-driven regulatory programs, including a core program shared across T(reg) cell subsets and effector-specific programs, both associated with NF-_B activity and Foxp3 binding. Thus, Foxp3 integrates cell-intrinsic and environmental contexts to drive epigenetic programs defining T(reg) cell identities and functions, with implications for Foxp3-based therapies.
Author Info:
(1) Laboratory of Immunology and Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan. (2) Laboratory of Immunology and Microbiology, Graduat
e School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan. (3) Laboratory of Immunology and Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan. Laboratory for Immune Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan. (4) Laboratory for Immune Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan. (5) Laboratory of Immunology and Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan. (6) Laboratory of Immunology and Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan. (7) Department of Applied Genomics, Kazusa DNA Research Institute, Chiba 292-0818, Japan. (8) Department of Experimental Pathology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan. (9) Department of Experimental Pathology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan. Laboratory of Experimental Immunology, Immunology Frontier Research Center, Osaka University, Osaka, Japan. (10) Laboratory of Immunology and Microbiology, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan. Laboratory for Immune Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.
Citation: Sci Immunol 2026 May 11:eaed2111 Epub05/01/2026
