title: A glucocorticoid amplifies IL-2-induced selective expansion of CD4(+)CD25(+)FOXP3(+) regulatory T cells in vivo and suppresses graft-versus-host disease after allogeneic lymphocyte transplantation.
abstract: Regulatory T (Treg) cells are a subpopulation of T cells that not only prevent autoimmunity, but also control a wide range of T cell-dependent immune responses. Glucocorticoid treatment (dexamethasone, or Dex) has been reported to amplify IL-2-mediated selective in vivo expansion of Treg cells. We simultaneously administered Dex and IL-2 to the donor in a murine allogeneic lymphocyte transplantation model to expand functional suppressive CD4(+)CD25(+)FOXP3(+) T cells in the graft and to raise the regulatory T cell/effector T cell (Treg/ Teff ) ratio to prevent graft-versus-host disease (GVHD). After combined treatment of the donor with Dex (5 mg/kg/day) and IL-2 (300,000 IU/mouse/day) for 3 days, grafts were subjected to flow cytometric analysis, and transplantation was carried out from male C57BL/6 mice to female BALB/c mice aged 8-12 weeks. Results showed that short-term simultaneous administration of Dex and IL-2 markedly expanded functional suppressive CD4(+)CD25(+)FOXP3(+) T cells in the murine spleen. In this murine allogeneic transplantation model, the grafts from donors with Dex and IL-2 pre-treatment led to a longer survival time for the recipients than for the control group (median survival time > 60 day vs. 12 day, P=0.0002). The ratio of Treg/Teff also increased remarkably (0.43+/-0.15 vs. 0.14+/-0.01, P=0.01). This study demonstrated that co-stimulation with Dex and IL-2 selectively expanded functional CD4(+)CD25(+)FOXP3(+) T cells in vivo, and that grafts from donors pre-treated with Dex and IL-2 led to longer survival time and greater suppression of GVHD after allogeneic transplantation. Thus, GVHD can be suppressed by the specific expansion of regulatory T cells with Dex and IL-2 in graft donors.
authors.affiliation: Department of Hematology, Huashan Hospital Affiliated to Fudan University, Shanghai 200040, China. xyh@medmail.com.cn
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Xie
authors.forename: Min
authors.initials: M
authors.lastname: Wu
authors.forename: Runhua
authors.initials: R
authors.lastname: Song
authors.forename: Jiexian
authors.initials: J
authors.lastname: Ma
authors.forename: Yi
authors.initials: Y
authors.lastname: Shi
authors.forename: Wenming
authors.initials: W
authors.lastname: Qin
authors.forename: Youxin
authors.initials: Y
authors.lastname: Jin
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D003907:Dexamethasone / Q000008:administration & dosage*; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage; D006086:Graft vs Host Disease / Q000276:immunology* / Q000517:prevention & control*; D007113:Immunity, Innate / Q000187:drug effects / Q000276:immunology*; D007376:Interleukin-2 / Q000276:immunology*; D017710:Lymphocyte Transfusion / Q000009:adverse effects*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology*
chemical_list: D005938:Glucocorticoids; D007376:Interleukin-2; D003907:Dexamethasone