Application of the rat liver lysosome assay to determining the reduction of toxic gliadin content during breadmaking.

Enriched caricain was able to detoxify a major proportion of the gliadin in wholemeal wheat dough by allowing it to react for 5h at 37 °C during the fermentation stage. A reduction of 82% in toxicity, as determined by the rat-liver lysosome assay, was achieved using 0.03% enzyme on weight of dough. Without enzyme, only 26% reduction occurred. The difference in reduction of toxicity achieved is statistically significant (p < 0.01). The results are very similar to those obtained in our previous work using an immuno assay and the same enzyme preparation. They confirm the value of caricain as a means of reducing the toxicity of gliadin and open the way for enzyme therapy as an adjunct to the gluten free diet. This approach should lead to better control over the elimination of dietary gluten intake in conditions such as coeliac disease and dermatitis herpetiformis.

Reduction of toxic gliadin content of wholegrain bread by the enzyme caricain.

Increasingly the number of individuals being diagnosed with some form of sensitivity to the proteins in wheat grains represents a cause for concern. Currently, the treatment is dietary withdrawal of gluten, but commercial gluten-free bread presents some undesirable properties. The objective of this study has been to assess the ability of the enzyme caricain (from papaya latex) to detoxify gliadin in whole wheat flour and develop bread suitable for coeliacs and gluten intolerant individuals. Ion exchange chromatography was used to enrich the caricain in papaya latex and an enzyme-linked immunosorbent assay test kit was used for the analysis of gliadin residues in the baked bread. The partially purified enzyme was found to be more effective in reducing gliadin content than the crude papain and the resultant loaves had acceptable crumb and crust characteristics. Caricain appears to be capable of detoxifying gliadin and has the potential to mitigate the problems confronting coeliacs.

Avenins from different cultivars of oats elicit response by coeliac peripheral lymphocytes.

OBJECTIVE: The avoidance of oats in coeliac patients is still controversial. If oats is confirmed to be safe, it would be a valuable component and offer more variation in a gluten-free diet. The aim of this work was to evaluate whether avenins from different varieties of oats show different abilities in the activation of coeliac peripheral lymphocytes. MATERIAL AND METHODS: In order to assess whether the immunogenic effect of oats varies according to the cultivar, peripheral lymphocytes from 10 coeliac children were exposed to avenins from four different oats varieties: Lampton, Astra, Ava and Nave. Lymphocyte proliferation and interferon-gamma (IFN-gamma) release in the culture medium were measured as indexes of immune activation. RESULTS: All the varieties of oats tested were immunogenic, with Lampton and Ava avenins inducing lymphocyte activation similar to that activated by wheat gliadin, while Astra and Nave avenins showed less immunogenicity, but still with a measurable effect. CONCLUSIONS: There are still concerns about the suitability of including oats in a gluten-free diet. Coeliac patients consuming oats-containing food should be carefully monitored, until there is more evidence to show the safety of oats and varieties of low-toxicity oats.

Enzyme therapy for management of coeliac disease.

OBJECTIVE: Enzyme therapy based on animal digestive extracts was investigated as a means of completely digesting toxic residues from gluten in the small intestine, thus providing a means of protection of the mucosa. MATERIAL AND METHODS: A randomized, placebo-controlled, clinical trial of an encapsulated enzyme extract was conducted in 21 coeliac patients in remission who were challenged with a modest amount of gluten daily over 2 weeks. Enzyme extract (900 mg) in three divided doses was administered during this challenge to half the group and a placebo to the other half in a double-blind, crossover design. Symptoms were recorded in daily diaries; blood was taken for tissue transglutaminase antibodies (anti-tTG) at the start and at intervals up to 12 weeks. Duodenal biopsies were performed for histological assessment at the start and end of each challenge period for 6 patients chosen at random from volunteers. After a further 10 weeks, the groups were changed over, and the same assessments carried out. RESULTS: Only 8 of the 21 patients (38%) had more than 5 episodes of moderate to severe symptoms during either of the gluten challenge periods, and in these, symptoms scores were ameliorated during enzyme therapy compared with the placebo period (p<0.02). Rises of 5 U/ml or more in anti-tTG occurred in only 5 patients at about 6-8 weeks after challenge, but were not correlated with symptoms. CONCLUSIONS: Only 1 of the 6 patients had normal histology at entry, thus focusing attention on the need for better management of the disease. By histological criteria, enzyme therapy offered better protection than placebo during the gluten challenges. The study supports the use of enzyme supplementation as a safeguard for patients with coeliac disease because of the difficulty of ensuring a strictly gluten-free diet.