Pine nut allergy: clinical features and major allergens characterization.
METHODS
The aims of this study were to evaluate IgE-mediated hypersensitivity to pine nut with details of clinical reactions and to characterize major pine nut allergens.


RESULTS
The study included ten consecutive teenagers and adults diagnosed with IgE-mediated clinical allergy to pine nut. Two major pine nut allergens were purified and identified and the secondary structures and susceptibility to digestion were characterized. Severe reactions represent 80% of allergic reactions to pine nut in this study. Moreover, 70% of the patients were monosensitized to this nut. Two major allergens with molecular weights of 6 and 50 kDa were purified and identified as albumin and vicilin, respectively. The 6 kDa protein (albumin), rich in α-helix content, was far more stable to peptic and tryptic digestion as compared with 50 kDa protein (vicilin), which was quickly broken down. The secondary structure of the purified 50 kDa protein showed 41% β-sheet, 5% α-helix, and 54% random coil and/or loops.


CONCLUSIONS
Eighty percent of allergic reactions to pine nut in the ten patients included in this study were severe. Most patients (70%) were monosensitized to this nut. Two major allergens with molecular weights of 6 and 50 kDa were purified and identified as albumin and vicilin, respectively.
Servicio de Alergia, Hospital Universitario 12 de Octubre, Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain. bcabanillas.hdoc@salud.madrid.org
Beatriz
B
Cabanillas
Hsiaopo
H
Cheng
Casey C
CC
Grimm
Barry K
BK
Hurlburt
Julia
J
Rodríguez
Jesús F
JF
Crespo
Soheila J
SJ
Maleki
D000293:Adolescent; D000328:Adult; D000418:Albumins / Q000276:immunology; D000485:Allergens / Q000009:adverse effects* / Q000737:chemistry / Q000276:immunology; D002942:Circular Dichroism; D003001:Cloning, Molecular; D003429:Cross Reactions / Q000276:immunology; D004311:Double-Blind Method; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D008297:Male; D008970:Molecular Weight; D021184:Nut Hypersensitivity / Q000175:diagnosis / Q000276:immunology*; D009754:Nuts / Q000737:chemistry* / Q000276:immunology; D010434:Pepsin A / Q000378:metabolism; D055314:Seed Storage Proteins / Q000276:immunology; D017422:Sequence Analysis, DNA; D014357:Trypsin / Q000378:metabolism; D055815:Young Adult
D000418:Albumins; D000485:Allergens; D055314:Seed Storage Proteins; D007073:Immunoglobulin E; C015575:vicilin protein, plant; D014357:Trypsin; D010434:Pepsin A