title: IL-10-dependent infectious tolerance after the treatment of experimental allergic encephalomyelitis with redirected CD4+CD25+ T lymphocytes.
abstract: How small numbers of CD4+CD25+ regulatory T cells suppress autoimmune responses in vivo is unclear. In this report we analyze the immunomodulatory activity of CD4+CD25+ T cells that are antigen-specifically redirected against myelin basic protein (MBP)89-101-specific autoreactive T cells by a MBP89-101-IA(s)-zeta chimeric receptor. We have previously shown that these redirected regulatory T cells are highly potent in treating a model autoimmune disease, experimental allergic encephalomyelitis. We show here that they have only limited effect in vivo on autoreactive T cell proliferation and therefore do not act by deleting or suppressing the expansion of pathologic effector cells. Rather, the redirected CD4+CD25+ T cells divert the pathologic T helper 1 self-specific T cell response to one characterized by high IL-10 and lower IL-4 production. Significantly, when isolated from the inducing CD4+CD25+ regulatory T cells, these self-specific T cells can independently suppress the autoreactive T cell response and experimental allergic encephalomyelitis development in an IL-10-dependent manner. These results provide evidence that CD4+CD25+ regulatory T cells can manipulate the adaptive immune response in vivo through the infectious induction of tolerance, specifically by promoting the formation of antigen-specific, IL-10-secreting regulatory T cells.
authors.affiliation: Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
authors.forename: Divya J
authors.initials: DJ
authors.lastname: Mekala
authors.forename: Rajshekhar S
authors.initials: RS
authors.lastname: Alli
authors.forename: Terrence L
authors.initials: TL
authors.lastname: Geiger
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D049109:Cell Proliferation; D016207:Cytokines / Q000276:immunology; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000276:immunology* / Q000473:pathology; D005260:Female; D007108:Immune Tolerance / Q000276:immunology*; D007167:Immunotherapy; D007239:Infections / Q000276:immunology / Q000473:pathology; D016753:Interleukin-10 / Q000276:immunology*; D051379:Mice; D015375:Receptors, Interleukin-2 / Q000276:immunology*
chemical_list: D016207:Cytokines; D015375:Receptors, Interleukin-2; D016753:Interleukin-10