These authors contributed equally to this work.
Is epitope recognition of shrimp allergens useful to predict clinical reactivity?
Article first published online: 22 DEC 2011
© 2011 Blackwell Publishing Ltd
Clinical & Experimental Allergy
Volume 42, Issue 2, pages 293–304, February 2012
How to Cite
- Issue published online: 30 JAN 2012
- Article first published online: 22 DEC 2011
- Manuscript Accepted: 11 OCT 2011
- Manuscript Revised: 19 SEP 2011
- Manuscript Received: 13 MAY 2011
- Food Allergy Initiative (FAI)
- World Allergy Organization
- Hospital Clínic de Barcelona, Emili Letang Award
- arginine kinase;
- food allergy;
- IgE epitope;
- microarray immunoassay;
- myosin light chain;
- sarcoplasmic calcium-binding protein;
Shrimp is a frequent cause of severe allergic reactions world-wide. Due to issues such as cross-reactivity, diagnosis of shrimp allergy is still inaccurate, requiring the need for double-blind, placebo-controlled food challenges (DBPCFC). A better understanding of the relationship between laboratory findings and clinical reactivity is needed.
To determine whether sensitization to certain shrimp allergens or recognition of particular IgE epitopes of those allergens are good biomarkers of clinical reactivity to shrimp.
Thirty-seven consecutive patients were selected with clinical histories of shrimp allergy. Skin prick test, specific IgE determinations, DBPCFC and immunoblot assays to shrimp extract were performed. IgE binding to synthetic overlapping peptides representing the sequence of the four allergens from the Pacific white shrimp (Litopenaeus vannamei) identified to date (Lit v1, Lit v2, Lit v3 and Lit v4) was analysed.
Of 37 (46%) patients, 17 had a positive challenge to shrimp (11 children and 6 adults). By microarray, patients with positive challenges showed more intense binding to shrimp peptides than those with negative challenges. Statistically significant differences in terms of the frequency and intensity of IgE binding to some epitopes were observed between the two groups. Diagnostic efficiency was higher for individual epitopes than for proteins. Particularly, efficiency was highest for certain Lit v 1 and Lit v 2 epitopes, followed by Lit v 3 and Lit v 4 epitopes.
Conclusion and Clinical Relevance
Patients with positive shrimp challenges present in general more intense and diverse epitope recognition to all four shrimp allergens. IgE antibodies to these shrimp epitopes could be used as biomarkers for prediction of clinical reactivity in subjects with sensitization to shrimp. Patients with positive shrimp challenges show more intense sensitization and more diverse epitope recognition. Several IgE-binding shrimp epitopes could be used as biomarkers for predicting clinical reactivity in subjects with sensitization to shrimp.