title: CD4+CD25-LAG3+ regulatory T cells controlled by the transcription factor Egr-2.
abstract: Regulatory T cells (Tregs) are engaged in the maintenance of immunological self-tolerance and immune homeostasis. IL-10 has an important role in maintaining the normal immune state. Here, we show that IL-10-secreting Tregs can be delineated in normal mice as CD4(+)CD25(-)Foxp3(-) T cells that express lymphocyte activation gene 3 (LAG-3), an MHC-class-II-binding CD4 homolog. Although approximately 2% of the CD4(+)CD25(-) T cell population consisted of CD4(+)CD25(-)LAG3(+) T cells in the spleen, CD4(+)CD25(-)LAG3(+) T cells are enriched to approximately 8% in the Peyer's patch. They are hypoproliferative upon in vitro antigenic stimulation and suppress in vivo development of colitis. Gene expression analysis reveals that CD4(+)CD25(-)LAG3(+) Tregs characteristically express early growth response gene 2 (Egr-2), a key molecule for anergy induction. Retroviral gene transfer of Egr-2 converts naïve CD4(+) T cells into the IL-10-secreting and LAG-3-expressing phenotype, and Egr-2-transduced CD4(+) T cells exhibit antigen-specific immunosuppressive capacity in vivo. Unlike Foxp3(+) natural Tregs, high-affinity interactions with selecting peptide/MHC ligands expressed in the thymus do not induce the development of CD4(+)CD25(-)LAG3(+) Tregs. In contrast, the number of CD4(+)CD25(-)LAG3(+) Tregs is influenced by the presence of environmental microbiota. Thus, IL-10-secreting Egr-2(+)LAG3(+)CD4(+) Tregs can be exploited for the control of peripheral immunity.
authors: Department of Allergy and Rheumatology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
authors: Tomohisa
authors: T
authors: Okamura
authors: Keishi
authors: K
authors: Fujio
authors: Mihoko
authors: M
authors: Shibuya
authors: Shuji
authors: S
authors: Sumitomo
authors: Hirofumi
authors: H
authors: Shoda
authors: Shimon
authors: S
authors: Sakaguchi
authors: Kazuhiko
authors: K
authors: Yamamoto
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis*; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D049109:Cell Proliferation; D051767:Early Growth Response Protein 2 / Q000378:metabolism / Q000502:physiology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D016753:Interleukin-10 / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000096:biosynthesis*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012190:Retroviridae / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D000093322:Lymphocyte Activation Gene 3 Protein
chemical_list: D015703:Antigens, CD; D051767:Early Growth Response Protein 2; C497327:Egr2 protein, mouse; D053645:Interleukin-2 Receptor alpha Subunit; D014157:Transcription Factors; D016753:Interleukin-10; D000093322:Lymphocyte Activation Gene 3 Protein