Art v 1 IgE epitopes of patients and humanized mice are conformational.
Allergy
Art v 1
IgE epitope
allergen
allergen-specific immunotherapy
epitope mapping
mugwort pollen allergy
Journal
The Journal of allergy and clinical immunology
ISSN: 1097-6825
Titre abrégé: J Allergy Clin Immunol
Pays: United States
ID NLM: 1275002
Informations de publication
Date de publication:
10 2022
10 2022
Historique:
received:
16
04
2021
revised:
31
03
2022
accepted:
21
04
2022
pubmed:
24
6
2022
medline:
12
10
2022
entrez:
23
6
2022
Statut:
ppublish
Résumé
Worldwide, pollen of the weed mugwort (Artemisiavulgaris) is a major cause of severe respiratory allergy, with its major allergen, Art v 1, being the key pathogenic molecule for millions of patients. Humanized mice transgenic for a human T-cell receptor specific for the major Art v 1 T-cell epitope and the corresponding HLA have been made. We sought to characterize IgE epitopes of Art v 1-sensitized patients and humanized mice for molecular immunotherapy of mugwort allergy. Four overlapping peptides incorporating surface-exposed amino acids representing the full-length Art v 1 sequence were synthesized and used to search for IgE reactivity to sequential epitopes. For indirect mapping, peptide-specific rabbit antibodies were raised to block IgE against surface-exposed epitopes on folded Art v 1. IgE reactivity and basophil activation studies were performed in clinically defined mugwort-allergic patients. Secondary structure of recombinant (r) Art v 1 and peptides was determined by circular dichroism spectroscopy. Mugwort-allergic patients and humanized mice sensitized by allergen inhalation showed IgE reactivity and/or basophil activation mainly to folded, complete Art v 1 but not to unfolded, sequential peptide epitopes. Blocking of allergic patients' IgE with peptide-specific rabbit antisera identified a hitherto unknown major conformational IgE binding site in the C-terminal Art v 1 domain. Identification of the new major conformational IgE binding site on Art v 1, which can be blocked with IgG raised against non-IgE reactive Art v 1 peptides, is an important basis for the development of a hypoallergenic peptide vaccine for mugwort allergy.
Sections du résumé
BACKGROUND
Worldwide, pollen of the weed mugwort (Artemisiavulgaris) is a major cause of severe respiratory allergy, with its major allergen, Art v 1, being the key pathogenic molecule for millions of patients. Humanized mice transgenic for a human T-cell receptor specific for the major Art v 1 T-cell epitope and the corresponding HLA have been made.
OBJECTIVE
We sought to characterize IgE epitopes of Art v 1-sensitized patients and humanized mice for molecular immunotherapy of mugwort allergy.
METHODS
Four overlapping peptides incorporating surface-exposed amino acids representing the full-length Art v 1 sequence were synthesized and used to search for IgE reactivity to sequential epitopes. For indirect mapping, peptide-specific rabbit antibodies were raised to block IgE against surface-exposed epitopes on folded Art v 1. IgE reactivity and basophil activation studies were performed in clinically defined mugwort-allergic patients. Secondary structure of recombinant (r) Art v 1 and peptides was determined by circular dichroism spectroscopy.
RESULTS
Mugwort-allergic patients and humanized mice sensitized by allergen inhalation showed IgE reactivity and/or basophil activation mainly to folded, complete Art v 1 but not to unfolded, sequential peptide epitopes. Blocking of allergic patients' IgE with peptide-specific rabbit antisera identified a hitherto unknown major conformational IgE binding site in the C-terminal Art v 1 domain.
CONCLUSIONS
Identification of the new major conformational IgE binding site on Art v 1, which can be blocked with IgG raised against non-IgE reactive Art v 1 peptides, is an important basis for the development of a hypoallergenic peptide vaccine for mugwort allergy.
Identifiants
pubmed: 35738928
pii: S0091-6749(22)00701-1
doi: 10.1016/j.jaci.2022.04.031
pii:
doi:
Substances chimiques
Allergens
0
Amino Acids
0
Antigens, Plant
0
Epitopes, T-Lymphocyte
0
Immune Sera
0
Immunoglobulin G
0
Peptides
0
Plant Proteins
0
Immunoglobulin E
37341-29-0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
920-930Informations de copyright
Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.