title: New cohorts of naive T cells exacerbate ongoing allergy but can be suppressed by regulatory T cells.
abstract: Although as pretreatment oral tolerance is a potent means to achieve systemic suppression, its application in ongoing disease is controversial. Here we propose that availability of naive T cells may critically determine whether immunological tolerance is achieved during ongoing antigenic reactivity. Infusion of naive antigen-specific T cells into mice directly prior to eliciting a secondary Th2 response induces these naive cells to actively engage in the antigenic response despite presence of established memory. Naive antigen-specific T-cells divided faster, produced more interleukin (IL)-2, IL-4 and IL-5 and enhanced immunoglobulin E (IgE) release during a secondary Th2 response, compared with naive T cells that were infused prior to a primary response. Despite such contribution by new cohorts of naive T cells co-infusion of mucosal Tr together with naive T cells could suppress enhanced IgE release during a secondary Th2 response. We conclude that naive T cells contribute to a secondary Th2 response and although they can still be suppressed in the presence of sufficient numbers of mucosal Tr, they may interfere with potential therapeutic application of mucosal tolerance.
authors.affiliation: Department of Molecular Cell Biology and Immunology, VU Medical Center, PO Box 7057, Amsterdam, the Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Hauet-Broere
authors.forename: W W J
authors.initials: WW
authors.lastname: Unger
authors.forename: L A
authors.initials: LA
authors.lastname: van Berkel
authors.forename: J
authors.initials: J
authors.lastname: Garssen
authors.forename: M A
authors.initials: MA
authors.lastname: Hoijer
authors.forename: G
authors.initials: G
authors.lastname: Kraal
authors.forename: J N
authors.initials: JN
authors.lastname: Samsom
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D006967:Hypersensitivity / Q000276:immunology* / Q000503:physiopathology*; D007108:Immune Tolerance; D007165:Immunosuppression Therapy; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D009092:Mucous Membrane / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology
chemical_list: D011948:Receptors, Antigen, T-Cell