Gibberellin-regulated protein in Japanese apricot is an allergen cross-reactive to Pru p 7.

Abstract

BACKGROUND:

Gibberellin-regulated protein (GRP, also known as peamaclein) was recently identified as a new marker allergen related to systemic reactions in peach allergy; however, its role in other fruit allergies is unknown.

OBJECTIVE:

To investigate the allergenicity of Japanese apricot (JA) GRP and clarify the clinical characteristics of JA allergy patients with GRP sensitization.

METHODS:

Seven patients (two males, five females, mean age 28.0 years) diagnosed with JA allergy based on relevant clinical history, positive skin test and/or challenge test were enrolled. JA GRP with a molecular weight of 6896.5 Da was purified by ion-exchange column chromatography. We performed enzyme-linked immunosorbent assay (ELISA), IgE-immunoblotting, basophil activating tests (BATs), and skin prick tests (SPTs) with purified JA GRP. To investigate the cross-reactivity between JA GRP and native Pru p 7 (nPru p 7), we performed ELISA inhibition tests. We measured specific IgE levels against apricot, peach, rPru p 1, rPru p 3, and rPru p 4 using ImmunoCAP.

RESULTS:

ELISA and IgE-immunoblotting using JA GRP showed positive reactions in six (85.7%) and seven (100%) patients, respectively. Five patients who provided informed consent for BATs and SPTs using JA GRP had positive results. In four patients who underwent ELISA inhibition tests using JA GRP and nPru p 7, IgE binding to one GRP inhibited binding to the other. The positivity for specific IgE against apricot, peach, rPru p 1, rPru p 3, and rPru p 4 was 14.3%, 57.1%, 0%, 0%, and 0%, respectively. Patients developed allergic reactions that were frequently accompanied with facial swelling, especially of the eyelids, which was dependent on cofactors, such as exercise.

CONCLUSIONS AND CLINICAL RELEVANCE:

These results indicated that GRP might be a causative allergen of JA allergy, whose onset frequently requires a cofactor, such as exercise, and might be cross-reactive between JAs and peaches.

• Authors: Naoko Inomata, Mami Miyakawa, Michiko Aihara
• Journal: Immunity, inflammation and disease (Immun Inflamm Dis) Vol. 5 Issue 4 Pg. 469-479 (12 2017) ISSN: 2050-4527 [Electronic] England
• PMID: 28685994 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2017 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

Chemical References

• Allergens
• Antigens, Plant
• Plant Proteins
• peamaclein protein, Prunus persica
• Immunoglobulin E

Topics

• Adolescent
• Adult
• Allergens (immunology)
• Amino Acid Sequence
• Antigens, Plant (immunology)
• Basophils (immunology, metabolism)
• Cross Reactions (immunology)
• Enzyme-Linked Immunosorbent Assay
• Female
• Food Hypersensitivity (diagnosis, immunology)
• Humans
• Immunization
• Immunoglobulin E (blood, immunology)
• Male
• Middle Aged
• Plant Proteins (immunology)
• Prunus armeniaca (immunology)
• Skin Tests
• Young Adult