title: Identification of an immunodominant IgE epitope of the Parietaria judaica major allergen.
abstract: Par j 1.0101 is one of the two major allergens of the Parietaria judaica (Pj) pollen, and its three-dimensional structure was built by three-dimensional structural homology modeling. The resultant model was used to identify putative IgE binding regions. Western blot analysis of gene fragmentation products showed that the 1 to 30 region was capable of binding specific IgE from a pool of sera (n = 30) of patients allergic to Pj pollen. Using the structural model as a guide, deletion and site-directed mutagenesis of the 1 to 30 region was performed, and the amino acids involved in IgE binding were identified. In addition, a synthetic peptide covering the 1 to 30 region was capable of binding human IgE without triggering histamine release from basophils of Pj allergic patients (n = 6) and thus represents a haptenic molecule with potential use as an immunotolerant agent. This epitope is also present on the Par j 2.0101 major allergen representing a common IgE epitope. It is an immunodominant epitope, since it was capable of inhibiting 30% of all specific IgE against the Pj major allergens, and therefore, it might be a candidate for the future development of immunotherapeutics.
authors.affiliation: Istituto di Biologia dello Sviluppo Consiglio Nazionale Delle Ricerche, Palermo, Italy. colombo@ibs.pa.cnr.it
authors.forename: P
authors.initials: P
authors.lastname: Colombo
authors.forename: D
authors.initials: D
authors.lastname: Kennedy
authors.forename: T
authors.initials: T
authors.lastname: Ramsdale
authors.forename: M A
authors.initials: MA
authors.lastname: Costa
authors.forename: G
authors.initials: G
authors.lastname: Duro
authors.forename: V
authors.initials: V
authors.lastname: Izzo
authors.forename: S
authors.initials: S
authors.lastname: Salvadori
authors.forename: R
authors.initials: R
authors.lastname: Guerrini
authors.forename: R
authors.initials: R
authors.lastname: Cocchiara
authors.forename: M G
authors.initials: MG
authors.lastname: Mirisola
authors.forename: S
authors.initials: S
authors.lastname: Wood
authors.forename: D
authors.initials: D
authors.lastname: Geraci
mesh_terms: D000485:Allergens / Q000737:chemistry / Q000276:immunology*; D000595:Amino Acid Sequence; D018604:Epitope Mapping; D006636:Histamine Release; D006801:Humans; D016056:Immunodominant Epitopes; D007073:Immunoglobulin E / Q000276:immunology*; D008961:Models, Structural; D008969:Molecular Sequence Data; D011058:Pollen / Q000276:immunology*
chemical_list: D000485:Allergens; D016056:Immunodominant Epitopes; D007073:Immunoglobulin E