Immunoglobulin E cross-reactivity between lupine conglutins and peanut allergens in serum of lupine-allergic individuals.
BACKGROUND
Lupine is used increasingly in food products. The development of lupine allergy in peanut-allergic patients is believed to occur as a result of cross-reactivity between lupine and peanut proteins.


OBJECTIVE
To investigate the degree of immunoglobulin (Ig) E cross-reactivity between allergens in lupine and peanut.


METHODS
We investigated IgE cross-reactivity between lupine alpha-, beta-, gamma-, and delta-conglutins and the major peanut allergens Ara h 1, Ara h 2 and Ara h 3 using enzyme-linked immunosorbent assay with sera from patients with coexisting peanut and lupine allergy.


RESULTS
Peanut proteins inhibited IgE binding towards alpha- conglutins, delta-conglutins, and, to a lesser degree, beta-conglutins, while no IgE cross-reaction with delta-conglutin was observed. Ara h 2 most potently inhibited IgE binding to lupine and delta-conglutins, while Ara h 1 most potently cross-reacted with beta-conglutin. Ara h 3 was apparently not involved in these mechanisms.


CONCLUSIONS
The present study reveals IgE cross-reactivity between the 2S albumins Ara h 2 and delta-conglutin, and the 7S vicilin-like Ara h 1 and beta-conglutin, which are possibly based on homologies between phylogenetically related proteins. Ara h 2 was the most potent inhibitor of IgE binding to lupine conglutins.
Dooper
M M B W
MM
National Veterinary Institute, Oslo, Norway.
Plassen
C
C
Holden
L
L
Lindvik
H
H
Faeste
C K
CK
D055516:2S Albumins, Plant / Q000276:immunology; D000293:Adolescent; D000485:Allergens / Q000276:immunology; D052179:Antigens, Plant / Q000276:immunology; D010367:Arachis / Q000276:immunology*; D001667:Binding, Competitive; D002648:Child; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes; D005260:Female; D005512:Food Hypersensitivity / Q000097:blood / Q000276:immunology*; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D031297:Lupinus / Q000276:immunology*; D008297:Male; D008565:Membrane Proteins; D021183:Peanut Hypersensitivity / Q000097:blood / Q000276:immunology; D010940:Plant Proteins / Q000276:immunology; D055314:Seed Storage Proteins / Q000276:immunology; D017386:Sequence Homology, Amino Acid
D055516:2S Albumins, Plant; D000485:Allergens; D052179:Antigens, Plant; C500889:Ara h 1 protein, Arachis hypogaea; C500890:Ara h 2 allergen, Arachis hypogaea; D000939:Epitopes; D006023:Glycoproteins; D008565:Membrane Proteins; D010940:Plant Proteins; D055314:Seed Storage Proteins; C118207:allergen Ara h3; C042457:conglutin protein, Lupinus angustifolius; D007073:Immunoglobulin E