title: In vivo modulation of antigen-experienced cells in response to high-dose oral antigen: deletion but no evidence for alterations in the cytokine phenotype.
abstract: Whether also antigen-experienced CD4(+) T cell populations undergo modulations upon oral antigen uptake supporting systemic unresponsiveness is still not fully understood. Using an adoptive transfer model with chicken ovalbumin (OVA)-specific T cells, we demonstrated that absolute numbers of transferred ex vivo-isolated CD4(+) memory T cells and in vitro-polarized T(h)1 cells considerably decrease within spleen and liver upon repetitive OVA feeding. As a consequence, these mice did not mount a delayed-type hypersensitivity reaction after OVA challenge. OVA-specific T(h)1 cells re-isolated from the liver showed augmented signs of apoptosis. However, there was no evidence that transferred effector or memory T cells acquired a regulatory phenotype, became anergic or underwent immune deviation. Our data suggest that oral antigen application does not induce alterations in the phenotype of CD4(+) effector and memory T cells. Instead, deletion of antigen-experienced CD4(+) T cells preferentially within the liver might be a major mechanism contributing to antigen-specific systemic unresponsiveness upon oral antigen uptake.
authors.affiliation: Experimentelle Rheumatologie, Charité Campus Mitte, Berlin, Germany.
authors.forename: Friderike
authors.initials: F
authors.lastname: Blumenthal-Barby
authors.forename: Katharina
authors.initials: K
authors.lastname: Eulenburg
authors.forename: Arnhild
authors.initials: A
authors.lastname: Schrage
authors.forename: Martin
authors.initials: M
authors.lastname: Zeitz
authors.forename: Alf
authors.initials: A
authors.lastname: Hamann
authors.forename: Katja
authors.initials: K
authors.lastname: Klugewitz
mesh_terms: D000284:Administration, Oral; D019264:Adoptive Transfer; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002452:Cell Count; D017637:Clonal Deletion; D016207:Cytokines / Q000378:metabolism; D007156:Immunologic Memory; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology; D037182:T-Cell Antigen Receptor Specificity / Q000187:drug effects / Q000276:immunology; D018417:Th1 Cells / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D014611:Vaccination
chemical_list: D016207:Cytokines; D010047:Ovalbumin