Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2011 Jul;60(7):915-22.
doi: 10.1136/gut.2010.225268. Epub 2011 Feb 12.

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

Affiliations

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

Isabel Comino et al. Gut. 2011 Jul.

Abstract

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 diet.

PubMed Disclaimer

Conflict of interest statement

Competing interests: None.

Figures

Figure 1
Figure 1
Evaluation of the presence of amplifiable DNA in oat varieties, wheat and rice by PCR. An ethidium bromide-stained agarose gel with oat, barley, rye and wheat PCR amplification products of two representative oat samples and other cereals (wheat and rice). MW, DNA molecular weight marker. Positive controls: DNA of these cereals amplified with 18S primers. The corresponding primers used were: (a) 18S; (b) ω-avenin; (c) ω-hordein; (d) ω-secalin; and (e) ω-gliadin. A representative example from the two biological replicates performed is shown.
Figure 2
Figure 2
Comparison of avenin fractions extracted from the oat varieties studied. Avenin spectra were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of the nine oat varieties. Analysis of proteins extracted from the oat varieties by sodium dodecyl sulfate–polyacrylamide gel electrophoreis (SDS–PAGE). MW, protein molecular weight marker.
Figure 3
Figure 3
Relative affinity of the monoclonal antibody (moAb) G12 for different oat varieties and gliadin. (A) Competitive ELISA using the anti-33-mer horseradish peroxidase-conjugated G12 to determine the relative affinity of this antibody for the different varieties of oat. Three assays were performed, with three replicates of each. (B) IC50 and CR of the different oat varieties. N.A., not applicable. (C) Western blot analysis of toxic fractions from different oat prolamins. Membranes were stained with the moAb G12. The colour code for labelling the varieties is the same as that used in A and B. MW, protein molecular weight marker.
Figure 4
Figure 4
Detection of the concentration of the 33-mer peptide in different oat varieties. The concentration of 33-mer was determined by competitive ELISA using the monoclonal antibody (moAb) G12 conjugated to horseradish peroxidase. Different independent dilutions were tested for each oat variety, each with three repetitions. The percentage of 33-mer of the variety assayed with respect to that of the most reactive variety (OM719). *The concentration of the 33-mer was lower than the limit of quantification of the competitive ELISA for the detection of 33-mer (5.4 ng/ml). N.A., not applicable.
Figure 5
Figure 5
Proliferative responses of T cells to deamidated peptides of prolamin from three different oat varieties. Peripheral blood mononuclear cells were stimulated by tissue transglutaminase-treated prolamin digest for 48 h. Gliadin and oryzein were used as the positive and negative control, respectively. The experiments were performed in duplicate and the mean stimulation index (SI) ±SD is shown. The SI values of T cells exposed to prolamin digests were statistically significant with respect to (A) the control (healthy patients) and (B) oryzein. *p
Figure 6
Figure 6
Interferon γ (IFN-γ) production by T cells with prolamin digests from three different oat varieties. T lymphocytes were stimulated with digested prolamins after treatment with tissue transglutaminase. IFN-γ production was evaluated by ELISA after 48 h of incubation. The results are shown as the means of duplicate wells and expressed as pg/ml. Gliadin and oryzein were used as the positive and negative control, respectively. Significant with respect to (A) healthy controls and (B) oryzein. *p

Similar articles

Cited by

References

    1. Bethune MT, Khosla C. Parallels between pathogens and gluten peptides in celiac sprue. PLoS Pathogens 2008;4:e34. - PMC - PubMed
    1. Anderson RP, Degano P, Godkin AJ, et al. In vivo antigen challenge in celiac disease identifies a single transglutaminase-modified peptide as the dominant A-gliadin T-cell epitope. Nat Med 2000;6:337–42 - PubMed
    1. Shan L, Molberg Ø, Parrot I, et al. Structural basis for gluten intolerance in celiac sprue. Science 2002;297:2275–9 - PubMed
    1. Tye-Din JA, Stewart JA, Dromey JA, et al. Comprehensive, quantitative mapping of T cell epitopes in gluten in celiac disease. Sci Transl Med 2010;2:41ra51 - PubMed
    1. Shan L, Qiao SW, Arentz-Hansen H, et al. Identification and analysis of multivalent proteolytically resistant peptides from gluten: implications for celiac sprue. J Proteome Res 2005;4:1732–41 - PMC - PubMed

Publication types

MeSH terms