title: Essential roles of CD8+CD122+ regulatory T cells in the maintenance of T cell homeostasis.
abstract: Regulation of immune system is of paramount importance to prevent immune attacks against self-components. Mice deficient in the interleukin (IL)-2/IL-15 receptor beta chain, CD122, are model animals of such immune attacks and characteristically have a high number of abnormally activated T cells. Here, we show that the transfer of CD8+CD122+ cells into CD122-deficient neonates totally prevented the development of abnormal T cells. Furthermore, recombination activating gene-2-/- mice that received wild-type mice-derived CD8+CD122- cells died within 10 wk after cell transfer, indicating that normal CD8+CD122- cells become dangerously activated T cells in the absence of CD8+CD122+ T cells. CD8+CD122+ cells could control activated CD8+ or CD4+ T cells both in vivo and in vitro. Our results indicate that the CD8+CD122+ population includes naturally occurring CD8+ regulatory T cells that control potentially dangerous T cells.
authors.affiliation: Dept. of Immunology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.
authors.forename: Muhaimin
authors.initials: M
authors.lastname: Rifa'i
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kawamoto
authors.forename: Izumi
authors.initials: I
authors.lastname: Nakashima
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Suzuki
mesh_terms: D000367:Age Factors; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D004268:DNA-Binding Proteins / Q000276:immunology; D005434:Flow Cytometry; D006706:Homeostasis / Q000276:immunology*; D051379:Mice; D008817:Mice, Mutant Strains; D016133:Polymerase Chain Reaction; D015375:Receptors, Interleukin-2 / Q000235:genetics / Q000276:immunology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; C499308:Rag2 protein, mouse; D015375:Receptors, Interleukin-2; C064655:V(D)J recombination activating protein 2