title: Ovalbumin-specific IgE modulates ovalbumin-specific T-cell response after repetitive oral antigen administration.
abstract: BACKGROUND
  Some patients outgrow their food allergies even though their serum antigen-specific IgE levels remain high.
  
  
  OBJECTIVE
  To elucidate the role of T cells in outgrowing food allergies in the presence of antigen-specific IgE, we tracked antigen-specific T-cell responses after oral antigen administration.
  
  
  METHODS
  Ovalbumin (OVA)-specific T-cell receptor (TCR) and OVA-specific IgE transgenic (Tg) mice (OVA-TCR/IgE-Tg) and OVA-specific TCR Tg (OVA-TCR-Tg) mice were fed with high doses of OVA or PBS every other day. After 7 administrations, OVA-specific proliferation and cytokine production of mononuclear cells of the spleen, mesenteric lymph nodes, and Peyer's patches and the number of splenic CD4 + CD25 + T cells were analyzed.
  
  
  RESULTS
  Without OVA administration, the splenocytes from OVA-TCR/IgE-Tg mice exhibited a higher proliferative response and produced more IL-4 and IL-10 and less IFN-gamma than those from OVA-TCR-Tg mice. The proliferative responses of the splenocytes from either OVA-TCR/IgE-Tg mice or OVA-TCR-Tg mice fed with OVA were significantly reduced compared with those from PBS-fed mice. The number of OVA-specific TCR + T cells decreased in the spleen from OVA-fed mice, whereas the number of CD4 + CD25 + T cells increased. The suppressed proliferation of splenocytes of OVA-fed mice was partially resumed by neutralization of TGF-beta1, but not of IL-10.
  
  
  CONCLUSIONS
  The presence of OVA-specific IgE modulated the OVA-specific responses of the splenocytes. Irrespective of the presence of OVA-specific IgE, repetitive oral administration of OVA induced tolerance, which seems to be composed of clonal deletion/anergy and TGF-beta1-mediated active suppression.
authors.affiliation: Department of Pediatrics, Faculty of Medical Sciences, University of Fukui, 2303 Shimoaizuki, Matsuoka-cho, Yoshida-gun, Fukui 910-1193, USA.
authors.forename: Nemuko
authors.initials: N
authors.lastname: Omata
authors.forename: Yusei
authors.initials: Y
authors.lastname: Ohshima
authors.forename: Motoko
authors.initials: M
authors.lastname: Yasutomi
authors.forename: Akiko
authors.initials: A
authors.lastname: Yamada
authors.forename: Hajime
authors.initials: H
authors.lastname: Karasuyama
authors.forename: Mitsufumi
authors.initials: M
authors.lastname: Mayumi
mesh_terms: D000284:Administration, Oral; D000818:Animals; D016207:Cytokines / Q000032:analysis / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D007108:Immune Tolerance; D007073:Immunoglobulin E / Q000276:immunology*; D051379:Mice; D008822:Mice, Transgenic; D010047:Ovalbumin / Q000008:administration & dosage* / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D016207:Cytokines; D011948:Receptors, Antigen, T-Cell; D007073:Immunoglobulin E; D010047:Ovalbumin