Pfiffner P, Stadler BM, Rasi C, et al. Cross-reactions vs co-sensitization evaluated by in silico motifs and in vitro IgE microarray testing

University Institute of Immunology, University of Bern, Switzerland.
Allergy (Impact Factor: 6.03). 11/2011; 67(2):210-6. DOI: 10.1111/j.1398-9995.2011.02743.x
Source: PubMed

ABSTRACT Using an in silico allergen clustering method, we have recently shown that allergen extracts are highly cross-reactive. Here we used serological data from a multi-array IgE test based on recombinant or highly purified natural allergens to evaluate whether co-reactions are true cross-reactions or co-sensitizations by allergens with the same motifs.
The serum database consisted of 3142 samples, each tested against 103 highly purified natural or recombinant allergens. Cross-reactivity was predicted by an iterative motif-finding algorithm through sequence motifs identified in 2708 known allergens.
Allergen proteins containing the same motifs cross-reacted as predicted. However, proteins with identical motifs revealed a hierarchy in the degree of cross-reaction: The more frequent an allergen was positive in the allergic population, the less frequently it was cross-reacting and vice versa. Co-sensitization was analyzed by splitting the dataset into patient groups that were most likely sensitized through geographical occurrence of allergens. Interestingly, most co-reactions are cross-reactions but not co-sensitizations.
The observed hierarchy of cross-reactivity may play an important role for the future management of allergic diseases.

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    • "They used the term “co-sensitization” to describe multiple, unrelated sensitizations to several structurally unrelated allergen groups. The structural basis of cross-reactivity was recently confirmed by Pfiffner et al. [16] in a micro-array study; 3,143 serum samples were tested to see whether they contained IgE that bound to any of 103 highly purified natural or recombinant allergens immobilized on the array. The researchers confirmed the previous cross-reactivity data from conventional IgE assays and reported predictions of cross-reactivity based on an iterative, motif detection algorithm. "
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