Location: Crop Improvement and Genetics ResearchTitle: Immunoglobulin-E-binding epitopes of wheat allergens in patients with food allergy to wheat and in mice experimentally sensitized to wheat proteins) Author
Submitted to: Clinical and Experimental Allergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/20/2011
Publication Date: 7/19/2011
Citation: Denery-Papini, S., Boninier, M., Pineau, F., Triballeau, S., Tranquet, O., Adel-Patient, K., Moneret-Vautrin, D.A., Bakan, B., Marion, D., Mothes, T., Mameri, H., Kasarda, D.D. 2011. Immunoglobulin-E-binding epitopes of wheat allergens in patients with food allergy to wheat and in mice experimentally sensitized to wheat proteins. Clinical and Experimental Allergy. 41(10):1478-1492. doi:10.1111.j.1365-2222.2011.03808.x. Interpretive Summary: Wheat grain proteins are commonly human allergens. In order to provide a basis for diminishing the allergenicity of wheat grain, further information about the structure of wheat allergens is needed. In this paper, the relationship between conformational structure and allergenicity has been investigated in regard to the type of epitopes (active amino acid sequences) expressed in the proteins. Compact conformational structure produces different epitopes from proteins with largely unstructured polypeptide chains. Mouse models of allergenicity were demonstrated to be useful in evaluating potential allergens.
Technical Abstract: Sera were obtained from 39 patients suffering from food allergy to wheat. Balb/c mice were sensitized to gliadins or LTP1 by intraperitoneal immunizations. Continuous epitopes bound by IgE were delineated by the Pepscan technique. The response to reduced, alkylated LTP1 was compared to that of the native form to evaluate the importance of protein folding on IgE reactivity. Few continuous epitopes of LTP1 reacted with IgE from allergic patients and mice, but one of them was common to several patients and sensitized mice. The unfolded protein was not recognized by either patient or mouse IgE, emphasizing the major role of LTP1 folding and discontinuous epitopes in IgE-binding. In contrast, many continuous epitopes were detected by patient and mouse IgE especially for an w5-gliadin, which is an unstructured protein, and to a lesser extent, for the other gliadinsand a LMW-glutenin subunit. The conformationa structures of LTP1 and w5-gliadin appeared to have a strong impact on the type of IgE-binding epitopes elicited by these proteins both in man and mouse. The responses in mice sensitized to gliadins or LTP1 were sufficiently comparable to the human response in terms of IgE-binding epitopes to provide support for the use of the mouse model in further investigations. Furthermore, differences for gliadin recognition between adults (many more continuous epitopes detected) and children were observed and may be linked to differentsensitization pathways.