*Current address: Division of Allergology, Paul-Ehrlich-Institute, Langen, Germany.
Digested Ara h 1 has sensitizing capacity in Brown Norway rats
Article first published online: 18 AUG 2009
© 2009 Blackwell Publishing Ltd
Clinical & Experimental Allergy
Volume 39, Issue 10, pages 1611–1621, October 2009
How to Cite
Bøgh, K. L., Kroghsbo, S., Dahl, L., Rigby, N. M., Barkholt, V., Mills, E. N. C. and Madsen, C. B. (2009), Digested Ara h 1 has sensitizing capacity in Brown Norway rats. Clinical & Experimental Allergy, 39: 1611–1621. doi: 10.1111/j.1365-2222.2009.03333.x
- Issue published online: 10 SEP 2009
- Article first published online: 18 AUG 2009
- Submitted 5 December 2008; revised 15 June 2009; accepted 16 June 2009
- animal model;
- Ara h 1;
- Brown Norway rats;
- food allergy;
Background Food allergies are a public health issue of growing concern, with peanuts in particular being associated with severe reactions. The peanut allergen, Ara h 1, belongs to the cupin plant food allergen family, which, unlike other structural families, appears to be broken down rapidly following gastrointestinal digestion.
Objective Using Ara h 1 as a model allergen, the ability of digested protein to sensitize has been investigated.
Methods Ara h 1 was purified from whole roasted peanuts. Intact Ara h 1 was digested in an in vitro model, simulating the human gastrointestinal digestion process. Digestion products were analysed for peptide sizes and their ability to aggregate. Brown Norway (BN) rats, used as an animal model, were immunized with purified intact Ara h 1 or the gastrointestinal digestion products thereof. The sensitizing capacity was evaluated by analyses of specific antibody (IgG1, IgG2a and IgE) responses and ability to trigger mediator release of rat basophilic leukaemia (RBL)-2H3 cells.
Results The present study showed that Ara h 1 was broken down, resulting in peptide fragments of sizes <2.0 kDa, of which approximately 50% was in aggregated complexes of Mr up to 20 kDa. Ara h 1 digesta were shown to have sensitizing capacity in BN rats, being capable of inducing specific IgG and IgE antibodies. The IgE response was functional, having the capacity to induce specific degranulation of RBL cells.
Conclusion From this study, it can be concluded that lability of a food allergen to gastrointestinal digestion does not necessarily abrogate its allergenic sensitizing potential.