title: Mechanisms of peripheral immune tolerance: conversion of the immune to the unresponsive phenotype.
abstract: Our studies on the immune response to foreign antigens are reviewed as they relate to the mechanisms of peripheral immune tolerance. The activation of suppressor T cells by distinct modes of antigen presentation is discussed. Through the use of mice expressing transgenic T-cell receptors specific for foreign antigens, we have concluded that the separable mechanisms of anergy and active suppression by CD25+ T cells work in concert to produce peripheral tolerance. In T-cell receptor Vbeta8.1 transgenic mice rendered tolerant of Mls-1a, the absence of the cell surface marker 6C10 defines the anergic population of CD4+ T cells, while 6C10+ CD4+ T cells are actively suppressed by CD25+ T cells. Through discussion of these observations, we have developed a historical perspective on recent advances in the understanding of mechanisms of peripheral tolerance.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine Philadelphia, PA 19104, USA.
authors.forename: Sandra J
authors.initials: SJ
authors.lastname: Saouaf
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Brennan
authors.forename: Yuan
authors.initials: Y
authors.lastname: Shen
authors.forename: Mark I
authors.initials: MI
authors.lastname: Greene
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D017635:Clonal Anergy; D006801:Humans; D007108:Immune Tolerance; D051379:Mice; D010641:Phenotype; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D015375:Receptors, Interleukin-2