title: Programmed cell death and extrathymic reduction of Vbeta8+ CD4+ T cells in mice tolerant to Staphylococcus aureus enterotoxin B.
abstract: Clonal deletion and functional inactivation of self-reactive cells have been invoked as mechanisms underlying intrathymic development of T-cell tolerance. The relative importance of these mechanisms in the development of tolerance of more mature, peripheral T cells either to self or to exogenous antigens is unclear, although recent data relate the development of T-cell tolerance in the periphery to clonal anergy. We have now investigated the induction of extrathymic tolerance using BALB/c mice that were made tolerant to Staphylococcus aureus enterotoxin B, a superantigen which specifically interacts in such mice with T cells bearing V beta 8 antigen receptors. Both euthymic and athymic mice made tolerant to S. aureus enterotoxin B had a markedly reduced number of V beta 8.1,2+ CD4+ peripheral T cells. This reduction was accompanied by genomic DNA fragmentation that is associated with cell death. These results indicate that a deletional mechanism can contribute to the induction of T-cell tolerance in peripheral lymphoid cells.
authors.affiliation: Department of Immunology and Medical Genetics, University of Toronto, Ontario, Canada.
authors.forename: Y
authors.initials: Y
authors.lastname: Kawabe
authors.forename: A
authors.initials: A
authors.lastname: Ochi
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016827:CD8 Antigens; D002470:Cell Survival / Q000276:immunology; D004247:DNA / Q000378:metabolism; D004768:Enterotoxins / Q000276:immunology*; D005434:Flow Cytometry; D015698:Genomic Library; D007108:Immune Tolerance / Q000276:immunology*; D008198:Lymph Nodes / Q000166:cytology; D051379:Mice; D008807:Mice, Inbred BALB C; D011948:Receptors, Antigen, T-Cell / Q000502:physiology*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D013997:Time Factors
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D016827:CD8 Antigens; D004768:Enterotoxins; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; C031818:enterotoxin B, staphylococcal; D004247:DNA