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.
Tsuji
Noriko M
NM
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
Kosaka
Akemi
A
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