Abstract
The major carrot allergen Dau c 1 belongs to the group of pathogenesis related class 10 (PR-10) proteins and is homologous to the birch pollen allergen Betv1. In contrast to most other PR-10 allergens, Dau c 1 can elicit Bet v 1 independent sensitization. Although Dau c 1 is considered heat labile, allergic reactions against cooked carrots are possible. The pH and temperature stability as well as the allergenic potential before and after treatment of purified natural (n) Dau c 1 and different recombinant (r) isoallergens is investigated: rDau c 1.0104, rDau c 1.0105, rDau c 1.0201, rDau c 1.0301. All proteins except rDau c 1.0201 are able to refold at physiological pH. pH conditions around the pI (4.4-5.5) or the presence of the carrot matrix reduce the refolding capacity. Below the pI, most isoallergens are heat resistant and still able to cause mediator release, indicating allergenicity. Moreover, cooked carrot extract is still able to provoke mediator release due to remaining soluble Dau c 1. Patients allergic to carrots should avoid processed carrot containing foodstuff because heating or pH treatment do not completely abolish the allergenicity of Dau c 1.
Highlights
Scope: The major carrot allergen Dau c 1 belongs to the group of pathogenesis related class 10 (PR-10) proteins
The isoallergen/variant composition of nDau c 1 purified from carrot extract was analyzed by liquid chromatography-mass spectrometry (LC-MS) (Table 1)
All other Dau c 1 proteins exhibited lower mediator release after heating to 95 °C, pH 3, the circular dichroism (CD) spectra recorded under these conditions showed that the secondary structures were retained (Figure 4)
Summary
Patients allergic to carrots should avoid processed carrot containing foodstuff because heating or pH treatment do not completely abolish the allergenicity of Dau c 1. The major carrot allergen in Central Europe, Dau c 1, is homol- allergen might affect its ability to be recognized by antibodies ogous to the birch pollen allergen Bet v 1 and belongs to the and subsequently its allergic properties.[8] Thermal processing may cause protein deterioration.[9] Heating can reduce the al-. 30, Bayreuth 95447, Germany lergenicity of PR-10 proteins, for example, in hazelnut, apple, or celeriac.[4,10,11] We have shown previously that recombinant (r)Api g 1.0101 is heat resistant in vitro. The allergenicity cannot be entirely abolished by food-processing, suggesting that Dau c 1-allergic patients should completely avoid Dau c 1-containing food stuff
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
