Differential immunomodulatory effects of Lactobacillus rhamnosus DR20, Lactobacillus fermentum CECT 5716 and Bifidobacterium animalis subsp. lactis on monocyte-derived dentritic cells

Abstract

In this study we have identified, for the first time to our knowledge plasma CD-specific IgA Abs that recognize as specific antigen a novel deamidated gliadin peptide (FPLQPEQP), derived from an 8-mer peptide generated during duodenal degradation of gliadin by CD-specific duodenal proteases. The native peptide (FPLQPQQP) remained restricted to prolamin and glutenin proteins from toxic cereals to CD patients and was particularly expressed in ω-prolamins. The 8-mer peptide overlapped with a previously identified gluten T cell epitope and its ability to develop a humoral immune response in vivo in CD patients was confirmed by the detection of IgA anti-DGP 8-mer Abs in plasma samples from those patients. The DGP 8-mer could be used as a novel specific CD antigen for the diagnosis of CD and monitoring of the compliance of GFD. We have designed an ELISA test which detects IgA anti-DGP 8-mer Abs in plasma samples from CD- patients with a high specificity (94% in children and 98.8% in adults) and sensitivity (93.5% in children and 81.3% in adults). Future studies with larger number of samples and additional relevant data (i.e. use of novel tools for GFD compliance) will assess the full potential of the novel diagnostic tool for celiac diagnosis and management.