A case of allergy to beer showing cross-reactivity between lipid transfer proteins.
BACKGROUND
Lipid transfer proteins (LTPs) are highly conserved proteins present in a broad spectrum of fruits and vegetables that might represent a novel plant panallergen.


OBJECTIVE
To demonstrate that LTP is an important allergen in beer and that beer LTP cross-reacts with LTP from botanically unrelated plant-derived foods.


METHODS
Serum from a patient with clinical allergy to both beer and Rosaceae was studied for IgE reactivity to LTP to several vegetable foods by RAST, ELISA, immunoblot, and inhibition studies.


RESULTS
Patient's serum showed a strong IgE reactivity to LTP purified from peach peel, carrot, and broccoli, and to a 10 kD protein in both apple and peach immunoblots, whereas no reactivity to birch cross-reactive allergens such as Bet v 1, profilin, or carbohydrates was found. In inhibition studies, preabsorption of serum with apple, walnut, hazelnut, peanut, corn, and rice caused a fall of 97%, 20%, 66%, 91%, 94%, and 93%, respectively, of its reactivity to peach LTP. Beer RAST fell from 1.8 IU/mL to <0.1 IU/mL when a patient's serum was preabsorbed with recombinant carrot LTP.


CONCLUSIONS
LTP is a relevant allergen in beer. Beer LTP may cross-react with LTP from several other plant-derived foods.
Asero
R
R
Ambulatorio di Allergologia, Ospedale Caduti Bollatesi, Bollate, MI, Italy. r.asero@libero.it
Mistrello
G
G
Roncarolo
D
D
Amato
S
S
van Ree
R
R
D000328:Adult; D001515:Beer / Q000009:adverse effects*; D002352:Carrier Proteins / Q000276:immunology*; D003429:Cross Reactions / Q000276:immunology; D005512:Food Hypersensitivity / Q000097:blood / Q000209:etiology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male
D002352:Carrier Proteins; C030363:lipid transfer protein; D007073:Immunoglobulin E