Respiratory allergy to lipid transfer protein.
BACKGROUND
Due to unclear reasons, allergy to lipid transfer protein (LTP) is frequent in Mediterranean countries but rare in Northern Europe.


OBJECTIVE
We report a paradigmatic case of primarily airborne sensitization to LTP that might explain the geographical distribution of this type of food allergy.


METHODS
A 21-year-old woman began having severe perennial rhinitis 6 months after she started working in a wholesale fruit storehouse in Southern Italy where large amounts of fruits, including peaches, were handled; symptoms subsided when she left the workplace for >5 days and relapsed as soon as she was back at work. Later on, she developed severe food allergies to peach, hazelnut, peanut, apricot, plum and tomato. The patient underwent a nasal challenge with peach peel extract, and IgE reactivity was assessed by immunoblot analysis.


RESULTS
In vivo and in vitro analyses showed sensitivity to LTP. The nasal challenge with peach peel extract (6 microg protein) induced acute, severe respiratory symptoms. On immunoblot with peach peel extract patient's serum reacted uniquely against LTP, as demonstrated by inhibition assays with the recombinant peach protein.


CONCLUSIONS
LTP may induce sensitization via the respiratory tract due to inhalation of air-dispersed food particles, and this may precede the onset of food allergy. If this way of sensitization were effective in the majority of LTP allergic patients (e.g. by exposure to peaches showing intact fuzz in areas where peaches are grown and directly sold on the market) our findings could explain the strange geographical distribution of this type of food allergy.
Borghesan
Franco
F
Dipartimento di Medicina di Laboratorio, Padova, Italy.
Mistrello
Gianni
G
Roncarolo
Daniela
D
Amato
Stefano
S
Plebani
Mario
M
Asero
Riccardo
R
D000485:Allergens / Q000276:immunology*; D002352:Carrier Proteins / Q000276:immunology*; D005260:Female; D005512:Food Hypersensitivity / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D005638:Fruit / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D019570:Inhalation Exposure / Q000009:adverse effects; D009299:Nasal Provocation Tests; D016273:Occupational Exposure / Q000009:adverse effects; D027861:Prunus / Q000276:immunology*; D012130:Respiratory Hypersensitivity / Q000097:blood / Q000175:diagnosis* / Q000276:immunology
D000485:Allergens; D002352:Carrier Proteins; C030363:lipid transfer protein; D007073:Immunoglobulin E