Can apples cure allergies?

Eating apples may offer an alternative approach to allergies, according to researchers at the Laimburg Research Centre. Together with other scientific partners they are now investigating this effect under the “AppleCare” project. In future, a doctor’s prescription could be something along the lines of “Eat half an apple each day for two years – Golden Delicious or similar – including the skin!”. It may in fact be possible to treat birch pollen allergy with an alternative approach, namely by eating apples. The Laimburg Research Centre is currently investigating this under the “AppleCare” project in collaboration with the dermatology departments at Bolzano Hospital, the University of Innsbruck and the Innsbruck Medical University.

Conventional immunotherapy

During the peak flowering period for birch trees, the eyes, noses and throats of many allergy sufferers turn critical: the conjunctiva are irritated and mucous membranes are swollen. Antihistamines provide rapid relief, but only immunotherapy will help over the long term. To gradually accustom the immune system to the allergen, it is administered for years under the skin, a therapy that is often unpleasant for patients. Over 70% of all birch pollen allergy sufferers also experience the same symptoms when eating certain types of fruit, especially apples: itching in the mouth and throat, on the lips, tongue, and up to the ear canals. Certain immune systems “confuse” the apple with birch pollen, with the overreaction generating the classic symptoms. This cross-reaction is very uncomfortable for patients, but offers the possibility of curing the allergy by means of an alternative immunotherapy.

Apples as a therapeutic agent

The structure of the apple allergen is very similar to that of the birch. Swiss studies have already demonstrated the therapeutic effect of birch pollen extract on the apple allergy. Together with its project partners, the Laimburg Research Centre is now taking the opposite approach with the “AppleCare” project, exploring how the repeated consumption of the apple allergen can have positive effects in curing birch pollen allergy. Apples thus become a “drug” that is easier to tolerate than conventional therapy – and is available prescription-free in any supermarket. The “AppleCare” project sees agriculture meeting structural chemistry, molecular biology and immunology, as the project involves an interdisciplinary approach: clinical studies are combined with analyses based upon molecular biology and structural chemistry. The idea arose from a collaborative effort between Thomas Letschka, head of applied genomics and molecular biology at the Laimburg Research Centre, and Klaus Eisendle, consultant at the dermatology department of Bolzano Hospital. The two dermatology departments in Bolzano and at the University Hospital in Innsbruck have chosen 20 individuals from a variety of potential subjects who are best suited to this study. The results are compared with gene expression analyses at the Laimburg Research Centre and with chemical analyses for clarifying the structure of apple allergens at the University of Innsbruck. These analyses aim to answer the following question: which of the over 30 different apple allergens most contribute to allergies and are most similar to the birch pollen allergen? Once the best candidates are identified, their concentration in different apple varieties will be measured, thus allowing a suitable therapy approach to be developed.

A cure without injections or tablets

This natural immunotherapy – simply eating apples – aims to replace the current immunotherapy and thus to cure the allergy without the use of injections or tablets. As in all likelihood a cure for apple allergy is also associated with a cure for birch pollen allergy, apples can and should also continue to be enjoyed after the therapy.

Allergies in small children

Toddlers should also be exposed to any allergens as soon as possible, i.e. from the fourth month of age, rather than avoiding contact for as long as possible with potentially allergic foods such as apples or legumes. This significantly reduces the development of allergies, as has already clearly been shown in the case of peanuts.

Thomas Letschka – Laimburg Reserch Centre (published in Der Landwirt, no. 4, 02/03/2018