Diversity in oat potential immunogenicity: basis for the selection of oat varieties with no toxicity in coeliac disease

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/2.0/ and http://creativecommons.org/licenses/by-nc/2.0/legalcode.[Background and aims] Coeliac disease (CD) is triggered by an abnormal reaction to gluten. Peptides resulting from partially digested gluten of wheat, barley or rye cause inflammation of the small intestinal mucosa. Previous contradictory studies suggest that oats may trigger the abnormal immunological response in patients with CD. Monoclonal antibodies (moAbs) against the main immunotoxic 33-mer peptide (A1 and G12) react strongly against wheat, barley and rye but have less reactivity against oats. The stated aim of this study is to test whether this observed reactivity could be related to the potential toxicity of oats for patients with CD.[Methods] In the present study, different oat varieties, controlled for their purity and by their distinct protein pattern, were used to examine differences in moAb G12 recognition by ELISA and western blot. Immunogenicity of oat varieties was determined by 33-mer concentration, T cell proliferation and interferon γ production.[Results] Three groups of oat cultivars reacting differently against moAb G12 could be distinguished: a group with considerable affinity, a group showing slight reactivity and a third with no detectable reactivity. The immunogenicity of the three types of oats as well as that of a positive and negative control was determined with isolated peripheral blood mononuclear T cells from patients with CD by measurement of cell proliferation and interferon γ release. A direct correlation of the reactivity with G12 and the immunogenicity of the different prolamins was observed.[Conclusions] The results showed that the reactivity of the moAb G12 is proportional to the potential immunotoxicity of the cereal cultivar. These differences may explain the different clinical responses observed in patients suffering from CD and open up a means to identify immunologically safe oat cultivars, which could be used to enrich a gluten-free dietThis work was supported by Asociacio´n de Celı ´acos de Madrid (to SC) by grants PET2008_0055 from VI Plan Nacional de Investigacio´n Cientı ´fica, Desarrollo e Innovacio´n Tecnolo´gica (Ministerio de Ciencia e Innovacio´n), IAB (Instituto Andaluz de Biotecnologı ´a) (to SC) and by AGR2009-4966M (Proyecto de Excelencia, Junta de Andalucı ´a) (to TM). Biomedal thanks Corporacio´n Tecnolo´gica de Andalucı ´a and Agencia IDEA for co-founding this study (to CA).Peer reviewe