Oral tolerance: intestinal homeostasis and antigen-specific regulatory T cells.
Mucosal surfaces, especially those of the gastrointestinal (GI) tract, are sites for tolerance induction to numerous exogenous antigens (Ags), and provide a microenvironment suitable for generating tolerogenic dendritic cells (DCs) that contribute to the functional maturation of regulatory T cells. During immune homeostasis in the GI tract, innate immune signals provided by innocuous or commensal bacteria play important roles in stabilizing this noninflammatory microenvironment and function of regulatory T cells. Thus oral tolerance consists of two phases of immune response: the maintenance of homeostasis and the suppression of immune responses mediated by Ag-specific regulatory T cells. Elucidating mechanisms for both phases should contribute to physiological intervention of local and systemic immunity, thereby improving homeostasis in both health and disease.
Age Dimension Research Center, National Institute of AdvancedIndustrial Science and Technology (AIST), Tsukuba Central 6-13, Tsukuba, Ibaraki 305-8566, Japan. nm-tsuji@aist.go.jp
Noriko M
NM
Tsuji
Akemi
A
Kosaka
D000818:Animals; D000941:Antigens / Q000276:immunology*; D006706:Homeostasis / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology*; D018928:Immunity, Mucosal / Q000276:immunology; D007422:Intestines / Q000276:immunology*; D009061:Mouth Mucosa / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D000941:Antigens