title: Mechanisms of T cell peptide epitope-dependent late asthmatic reactions.
abstract: Short peptide sequences corresponding to T cell epitopes have been identified in the major cat allergen Fel d 1. In order to directly activate allergen-specific T cells in cat-allergic asthmatic individuals, peptides were administered by intradermal injection. Subsequently, a proportion of subjects experienced a delayed reduction of airway calibre manifested as a decrease in FEV(1). Changes in lung function occurred approximately 3 h after peptide injection, peaked at 6 h and resembled an isolated late asthmatic reaction (LAR). Using molecular tissue typing techniques, it was determined that many of the individuals experiencing isolated LAR expressed particular HLA-DR molecules. These molecules were shown in subsequent experiments to bind individual peptides within the preparation and thus to activate T cells in a major histocompatibility complex (MHC)-restricted fashion. The precise mechanisms whereby MHC-restricted activation of allergen-specific T cells gives rise to bronchoconstriction are currently under investigation.
authors: Allergy and Clinical Immunology, Imperial College School of Medicine, London, UK. m.larche@ic.ac.uk
authors: M
authors: M
authors: Larché
authors: B M
authors: BM
authors: Haselden
authors: W L
authors: WL
authors: Oldfield
authors: K
authors: K
authors: Shirley
authors: J
authors: J
authors: North
authors: Q
authors: Q
authors: Meng
authors: D S
authors: DS
authors: Robinson
authors: S
authors: S
authors: Ying
authors: A B
authors: AB
authors: Kay
mesh_terms: D000818:Animals; D001249:Asthma / Q000276:immunology*; D002415:Cats; D002460:Cell Line; D000939:Epitopes / Q000276:immunology*; D005541:Forced Expiratory Volume; D006023:Glycoproteins / Q000276:immunology; D006684:HLA-DR Antigens / Q000276:immunology; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology; D008213:Lymphocyte Activation; D010455:Peptides / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000939:Epitopes; D006023:Glycoproteins; D006684:HLA-DR Antigens; D010455:Peptides; C059296:Fel d 1 protein, Felis domesticus