title: Transfer of allergic airway responses with antigen-primed CD4+ but not CD8+ T cells in brown Norway rats.
abstract: Activated CD4+ helper T cells have been demonstrated in asthmatic airways and postulated to play a central role in eliciting allergic inflammation; direct evidence of their involvement seems to be lacking. We hypothesized that CD4+ T cells have the potential to induce allergic responses to antigen challenge, and tested this hypothesis in a model of allergic bronchoconstriction, the Brown Norway rat, using the approach of adoptive transfer. Animals were actively sensitized to either ovalbumin (OVA) or BSA and were used as donors of T cells. W3/25(CD4)+ or OX8(CD8)+ T cells were isolated from the cervical lymph nodes of sensitized donors and transferred to naive BN rats. 2 d after adoptive transfer recipient rats were challenged by OVA inhalation, and changes in lung resistance (RL), bronchoalveolar lavage (BAL) cells, and serum levels of antigen-specific IgE were studied. After OVA challenge recipients of OVA-primed W3/25+ T cells exhibited sustained increases in RL throughout the entire 8-h observation period and had significant bronchoalveolar lavage eosinophilia, which was detected by immunocytochemistry using an antimajor basic protein mAb. Recipients of BSA-primed W3/25+ T cells or OVA-primed OX8+ T cells failed to respond to inhaled OVA. OVA-specific immunoglobulin E was undetectable by ELISA or skin testing in any of the recipient rats after adoptive transfer. In conclusion, antigen-induced airway bronchoconstriction and eosinophilia were successfully transferred by antigen-specific W3/25+ T cells in Brown Norway rats. These responses were dependent on antigen-primed W3/25+ T cells and appeared to be independent of IgE-mediated mast cell activation. This study provides clear evidence for T cell mediated immune mechanisms in allergic airway responses in this experimental model.
authors.affiliation: Meakins-Christie Laboratories, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Watanabe
authors.forename: H
authors.initials: H
authors.lastname: Mishima
authors.forename: P M
authors.initials: PM
authors.lastname: Renzi
authors.forename: L J
authors.initials: LJ
authors.lastname: Xu
authors.forename: Q
authors.initials: Q
authors.lastname: Hamid
authors.forename: J G
authors.initials: JG
authors.lastname: Martin
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D004804:Eosinophils / Q000166:cytology / Q000276:immunology; D006967:Hypersensitivity / Q000276:immunology*; D007111:Immunity, Cellular; D007073:Immunoglobulin E / Q000032:analysis; D016219:Immunotherapy, Adoptive; D007249:Inflammation; D007958:Leukocyte Count; D008168:Lung / Q000276:immunology*; D008198:Lymph Nodes / Q000276:immunology; D008213:Lymphocyte Activation; D017710:Lymphocyte Transfusion; D008297:Male; D010047:Ovalbumin / Q000276:immunology; D051381:Rats; D011914:Rats, Inbred BN; D012137:Respiratory System / Q000276:immunology*; D012710:Serum Albumin, Bovine / Q000276:immunology; D012882:Skin Tests; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D000485:Allergens; D012710:Serum Albumin, Bovine; D007073:Immunoglobulin E; D010047:Ovalbumin