Search for low-allergenic apple cultivars for birch-pollen-allergic patients: is there a correlation between in vitro assays and patient response?
BACKGROUND
Due to the cross-reactivity between Bet v 1 and proteins present in vegetable foods, birch pollen allergic patients frequently develop allergy to fruits and vegetables, mostly apples. Since many apple cultivars exist some of them might contain sufficiently low amounts of Mal d 1 to be tolerated by most allergic patients.


OBJECTIVE
To assess whether apple cultivars containing low amounts of Mal d 1 are better tolerated by apple-allergic patients.


METHODS
Mal d 1 content was determined in many apple cultivars by ELISA. Selected cultivars containing high (Golden Delicious) or low (Orim, G 198 and Vienna) amounts of Mal d 1 were compared in apple allergic patients both by SPT and oral challenges.


RESULTS
The 3 different apple cultivars induced wheals of similar size in most patients. Upon oral challenges no patient reported the total absence of oral symptoms following the ingestion of either high or low allergenic apples. Golden Delicious and G-198 elicited OAS of similar severity 3/7 cases. The 2 cultivars induced significantly more severe symptoms in 2 cases each.


CONCLUSIONS
Allergy to Mal d 1 is characterized by significant inter-patient variability. Moreover, marked inter-apple and intra-apple variability exists. As a consequence, the amount of Mal d 1 in apples classified as containing low concentrations of allergen may be sufficient to induce both clinical symptoms and skin reactivity in birch pollen-allergic patients. The search for low allergenic apples therefore should be continued and extended to other germplasm accessions, be it cultivars, breeding lines or wild species.
Asero
R
R
Ambulatorio di Allergologia, Clinica San Carlo, Paderno Dugnano, MI, Italy.
Marzban
G
G
Martinelli
A
A
Zaccarini
M
M
Machado
M Laimer da Camara
ML
D000284:Administration, Oral; D000328:Adult; D000485:Allergens / Q000009:adverse effects* / Q000276:immunology; D000799:Angioedema / Q000209:etiology; D052179:Antigens, Plant; D001947:Breeding; D003429:Cross Reactions; D005260:Female; D005512:Food Hypersensitivity / Q000209:etiology / Q000517:prevention & control*; D014644:Genetic Variation; D006636:Histamine Release; D006801:Humans; D008297:Male; D027845:Malus / Q000009:adverse effects* / Q000145:classification / Q000235:genetics / Q000276:immunology; D008875:Middle Aged; D010940:Plant Proteins / Q000009:adverse effects* / Q000276:immunology; D011058:Pollen / Q000009:adverse effects*; D011537:Pruritus / Q000209:etiology; D016037:Single-Blind Method; D012882:Skin Tests
D000485:Allergens; D052179:Antigens, Plant; C095551:MALD1 protein, Malus domestica; D010940:Plant Proteins; C061312:Bet v 1 allergen, Betula