title: Continuous exposure of mice to superantigenic toxins induces a high-level protracted expansion and an immunological memory in the toxin-reactive CD4+ T cells.
abstract: We analyzed the responses of several T cell fractions reactive with superantigenic toxins (SAGTs), staphylococcal enterotoxin A (SEA), or Yersinia pseudotuberculosis-derived mitogen (YPM) in mice implanted with mini-osmotic pumps filled with SEA or YPM. In mice implanted with the SEA pump, SEA-reactive Vbeta3(+)CD4(+) T cells exhibited a high-level protracted expansion for 30 days, and SEA-reactive Vbeta11(+)CD4(+) T cells exhibited a low-level protracted expansion. SEA-reactive CD8(+) counterparts exhibited only a transient expansion. A similar difference in T cell expansion was also observed in YPM-reactive T cell fractions in mice implanted with the YPM pump. Vbeta3(+)CD4(+) and Vbeta11(+)CD4(+) T cells from mice implanted with the SEA pump exhibited cell divisions upon in vitro restimulation with SEA and expressed surface phenotypes as memory T cells. CD4(+) T cells from mice implanted with the SEA pump exhibited high IL-4 production upon in vitro restimulation with SEA, which was due to the enhanced capacity of the SEA-reactive CD4(+) T cells to produce IL-4. The findings in the present study indicate that, in mice implanted with a specific SAGT, the level of expansion of the SAGT-reactive CD4(+) T cell fractions varies widely depending on the TCR Vbeta elements expressed and that the reactive CD4(+) T cells acquire a capacity to raise a memory response. CD8(+) T cells are low responders to SAGTs.
authors.affiliation: Department of Microbiology and Immunology, School of Medicine, Tokyo Women's Medical University, Ohtsu, Japan.
authors.forename: Luqiu
authors.initials: L
authors.lastname: Chen
authors.forename: Madoka
authors.initials: M
authors.lastname: Koyanagi
authors.forename: Kenji
authors.initials: K
authors.lastname: Fukada
authors.forename: Ken'ichi
authors.initials: K
authors.lastname: Imanishi
authors.forename: Junji
authors.initials: J
authors.lastname: Yagi
authors.forename: Hidehito
authors.initials: H
authors.lastname: Kato
authors.forename: Tohru
authors.initials: T
authors.lastname: Miyoshi-Akiyama
authors.forename: Ruihua
authors.initials: R
authors.lastname: Zhang
authors.forename: Keishi
authors.initials: K
authors.lastname: Miwa
authors.forename: Takehiko
authors.initials: T
authors.lastname: Uchiyama
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000008:administration & dosage / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D002455:Cell Division / Q000276:immunology; D002478:Cells, Cultured; D002999:Clone Cells; D016207:Cytokines / Q000096:biosynthesis; D004768:Enterotoxins / Q000008:administration & dosage / Q000097:blood / Q000276:immunology*; D005260:Female; D007156:Immunologic Memory / Q000276:immunology*; D015918:Infusion Pumps, Implantable; D007274:Injections, Intraperitoneal; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D008934:Mitogens / Q000008:administration & dosage / Q000276:immunology*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis; D018089:Superantigens / Q000008:administration & dosage / Q000097:blood / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D015011:Yersinia pseudotuberculosis / Q000276:immunology*
chemical_list: D001426:Bacterial Proteins; D016207:Cytokines; D004768:Enterotoxins; D008934:Mitogens; D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens; C093313:Yersinia pseudotuberculosis-derived mitogen; C026066:enterotoxin A, Staphylococcal