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

Abstract

Background and aimsCoeliac 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.MethodsIn 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.ResultsThree 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.ConclusionsThe 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.

Intentional and inadvertent non-adherence in adult coeliac disease. A cross-sectional survey

“…of agreement over what constitutes a strict GFD, for example, in relation to some foods such as different strains of oats (Comino et al, 2011).…”

Kernel‐based gluten contamination of gluten‐free oatmeal complicates gluten assessment as it causes binary‐like test outcomes

“…To expand the dietary options of patients with CD, as well as those following a GF diet, many researchers have investigated the suitability of dietary inclusion of oats (Lundin et al, 2003;Thompson, 2003;Comino et al, 2011Comino et al, , 2015Londono et al, 2013;Tapsas et al, 2014). Although there has been debate whether oats present risks to patients with CD (Comino et al, 2011(Comino et al, , 2015Londono et al, 2013), increasing amounts of clinical data show that most patients with CD can tolerate dietary intake of oats (Lundin et al, 2003;Thompson, 2003;Tapsas et al, 2014). Therefore, inclusion of pure oats in a GF diet is considered safe (Janatuinen et al, 1995;Lundin et al, 2003;Thompson, 2003;Tapsas et al, 2014) and viewed as a way to expand dietary options and improve nutritional status of GF conscious consumers (Comino et al, 2015).…”

“…Oats are recognised as one of the most important whole grain foods, being rich in dietary fibre, B-complex vitamins (thiamin, niacin and riboflavin), iron and proteins (Comino et al, 2015;Rebello et al, 2016). To expand the dietary options of patients with CD, as well as those following a GF diet, many researchers have investigated the suitability of dietary inclusion of oats (Lundin et al, 2003;Thompson, 2003;Comino et al, 2011Comino et al, , 2015Londono et al, 2013;Tapsas et al, 2014). Although there has been debate whether oats present risks to patients with CD (Comino et al, 2011(Comino et al, , 2015Londono et al, 2013), increasing amounts of clinical data show that most patients with CD can tolerate dietary intake of oats (Lundin et al, 2003;Thompson, 2003;Tapsas et al, 2014).…”

The safety of oats in the dietary treatment of coeliac disease

“…There is also the issue of how the oat material used in the clinical trial has been tested for contamination of gluten. In view of recent studies particularly on oat cultivar (30) , the whole area of accurate comparison has further been compounded as the vast majority of studies do not mention the variety of oat used.…”

“…However, a more recent study of the impact of oats using specific monoclonal antibodies showed more precise results (30) . This research group demonstrated variation in response to different cultivars of oats.…”