Identification, characterization, and initial epitope mapping of pine nut allergen Pin k 2

Area of Science:

• Food allergy research
• Molecular allergology
• Plant biochemistry

Background:

• Pine nut allergy is a significant concern, with vicilin identified as a potential allergen in Korean pine (Pinus koraiensis).
• Understanding specific allergens is crucial for accurate diagnosis and management of food allergies.

Purpose of the Study:

• To predict, identify, and characterize Korean pine vicilin as a pine nut allergen.
• To investigate the allergenic potential of both natural and recombinant Korean pine vicilin.
• To analyze the chemical and thermal stability of Korean pine vicilin.

Main Methods:

• Recombinant Korean pine vicilin was expressed in E. coli and purified.
• Natural and recombinant vicilin were tested for IgE recognition by Western blot using sera from 14 patients with diagnosed pine nut allergy.
• Chemical and thermal stability were assessed using circular dichroism and urea-induced unfolding.

Main Results:

• Twenty-nine percent of patient sera recognized both natural and recombinant Korean pine vicilin, confirming it as a bona fide food allergen.
• Analysis of natural protein fragments suggested potential linear IgE epitope mapping at fragment boundaries.
• Recombinant Korean pine vicilin exhibited a thermal transition at Tm=76.6°C and urea-induced unfolding at Cm=4.6M.

Conclusions:

• Korean pine vicilin is a validated food allergen responsible for pine nut allergy.
• The study provides insights into IgE epitope mapping and the stability characteristics of this important allergen.