- Ads -
Scientific Books
Dietary Management
Ernährung und Allergie

Internet Symposium on Food Allergens 2(Suppl. 4): 1-23 (2000) http://www.food-allergens.de
Subscribe: Online Access
Allergen Data Collection - Update:
Apple (Malus domestica)

Authors in alphabetical order [contact information]
BESLER (Hamburg, Germany)
ORTOLANI (Milan, Italy)
VIETHS (Langen, Germany)


The prevalence of apple allergy is most frequently associated with birch pollinosis in Northern Europe and North America. 40 to 90 % of birch pollen allergic patients are sensitized to apples. There is evidence for the predominant sensitization route by birch pollen allergens. Apple is known as one of the major foods involved in so-called "Oral Allergy Syndrome", which presents IgE-mediated symptoms occurring mainly at the mucosa of lips, tongue and throat after ingestion of apples and other fruits. Systemic reactions including anaphylaxis occur more frequently in apple allergic patients without related pollinosis.
There are differences in the allergenic potencies of different apple varieties and ripening stages of the fruits. Peels are more allergenic than pulps. The pollen related allergens are unstable to conventional processing of the fruits like canning, pulping or heating, therefore adverse reactions occur almost exclusively after ingestion of fresh fruits. Due to the labile nature of apple allergens diagnostic accuracy is highly dependent on the quality of extracts used in testing procedures.
Up to now four groups of cross-reactive allergens have been recognized in Rosaceae fruits (e.g. apple, apricot, cherry, pear, peach, and plum): 1. Pathogenisis related proteins like the major apple allergen Mal d 1, which are homologue to Bet-v-1 from birch pollen. 2. Glycoproteins in the range of 30-70 kDa, including a 35 kDa allergen cross-reactive to birch pollen and a 60 kDa allergen cross-reactive to mugwort pollen. 3. Actin-regulating profilins of appr. 14 kDa acting as panallergens. 4. Lipid-transfer proteins, which seem to be relevant in a smaller subpopulation of apple allergic individuals without birch pollinosis (9 kDa apple allergen Mal d 3). Lipid-transfer proteins are thought to be potentially stable allergens. Furthermore a thaumatin-homologue allergen, Mal d 2, has been characterized.
The present data collection reviews detailed information on the prevalence and symptoms of apple allergy as well as cross-reactivities, and molecular biological and allergenic properties of the major apple allergens in tabular form.
1 Prevalence of Apple Allergy
2 Symptoms of Apple Allergy
3 Diagnostic Features of Apple Allergy
4 Therapy of Apple Allergy
5 Composition of Apple
6 Allergens of Apple
6.1 Sensitization to Apple Allergens
6.2 Properties of Bet-v-1-homologous Protein (Mal d 1)
6.3 Properties of Thaumatin-homologous Protein 
(Mal d 2)
6.4 Properties of Lipid-transfer Protein (Mal d 3)
6.5 Properties of Apple Profilin
7 Isolation & Preparation
8 Cross-Reactivities
9 Stability of Apple Allergens
10 Allergen Sources
11 Allergenicity of Different Apple Varieties
12 References

The reference lists of the Allergen Data Collections are based mainly on searches of Medline and FSTA (Food Science & Technology Abstracts) databases up to the related dates of publication. The scientific rigor of the studies listed is variable and not subject of critique or evaluation by the authors or the editor of the Allergen Data Collections. The reader should be aware of considerable problems in comparing data from different studies (eg. patient cohorts, diagnostic performances, possible flaws in allergen preparations and methodologies for allergen characterization) and is encouraged to review the original publications.
The information provided by the Internet Symposium on Food Allergens is for educational, communication and information purposes only and is not intended to replace or constitute medical advice or treatments. Neither the authors nor the editorial board of the Internet Symposium on Food Allergens are responsible for use which might be made of the information.

copyright © 2000 by matthias besler -  ONLINE PUBLISHER
home: www.food-allergens.de