The interaction of dietary fibres with disulphide bonds (S-S) and a potential strategy to reduce the toxicity of the gluten proteins in coeliac disease

With a prevalence of 1% in western populations, coeliac disease (CD) is one of the better understood human leukocyte antigen system (HLA) linked disorders (Green and Cellier 2007). Despite the fact that CD shares immunological features with inflammatory bowel disease, it is characterized by: (1) a defined trigger (prolamins from wheat, barley and rye and in some individuals, oats); (2) the presence of HLA class II genes, HLA-DQ2 or HLA-DQ8, and (3) the generation of circulating auto antibodies to the enzyme tissue transglutaminase (TG2). TG2 catalyses the formation of a covalent bond between protein free amino groups and the g-carboxamide groups of glutamine residues, which constitute some 30-40 mol%, of the prolamins, this increases their affinity to HLA-DQ2 or HLA-DQ8 proteins (Schuppan 2000). As a result, CD4 T-helper 1 T-cell activation occurs, which can result in intestinal mucosal inflammation, malabsorption, and numerous secondary complications. When conducting severity assessments of coeliac disease, duodenal histology showing intraepithelial lymphocytosis, crypt hyperplasia, and various degrees of villous atrophy, in conjunction with clinical observations, are considered to be the gold standard for diagnosis.