T-cell response to different cultivars of farro wheat, Triticum turgidum ssp. dicoccum, in celiac disease patients (original) (raw)
Related papers
Cereal Research Communications, 2015
Enzyme-linked immunosorbent assays (ELISAs) are widely used to determine gluten contamination in gluten-free and low gluten food samples. ELISA assays developed using monoclonal antibodies against known toxic peptides have an advantage in the identification of toxic prolamin content in protein extracts of different food samples, as well as raw materials. R5 and G12 monoclonal antibodies specific for two known toxic peptides used in commercially available gluten ELISA assays were applied to test toxic peptide contents in wheat relatives and wild wheat species with different genome composition and complexity. Although the R5 peptide content showed some correlation with ploidy levels in Triticum species, there was a high variance among Aegilops species. Some of the analysed diploid Aegilops species showed extremely high R5 peptide contents. Based on the bioinformatics analyses, the R5 peptide was present in most of the sulphur rich prolamins in all the analysed species, whereas the G12 epitope was exclusively present in alpha gliadins. High variation was detected in the position and frequency of epitopes in sequences originating from the same species, thus highlighting the importance of genotypic variation within species. Identification of new prolamin alleles of wheat relatives and wild wheat species is of great importance in order to find germplasm for special end-use quality purposes as well as development of food with reduced toxicity.
Journal of Gastroenterology and Hepatology, 2007
In the present paper, the toxicity of prolamines derived from three cereals with a different genome was investigated in human colon cancer Caco-2/TC7 and human myelogenous leukemia K562(S) cells. The purpose of this study was to investigate if species from ancient wheat could be considered as healthy food crops devoid or poor in cytotoxic prolamines for celiac disease. Methods: Cytotoxicity was measured in terms of inhibition of cell growth, activation of apoptosis, release of nitric oxide (NO), detection of tissue transglutaminase (TG II) and alteration of transepithelial electrical resistance (TEER) on Caco-2/Tc7 and K562 (S) cell agglutination. Peptic-tryptic (PT) digest from bread wheat (T. aestivum S. Pastore) was used as a positive control. Results: PT digests of prolamins from spelt wheat (T. aestivum ssp. spelta) were found to exert toxic effects on Caco-2/TC7 cells and to agglutinate K562(S) cells. Increased amounts of NO and TG II expression were observed in Caco-2/TC7 cells exposed to 1 mg/mL of spelt prolamins, suggesting that spelt wheat can induce cellular mechanisms implicated in the pathogenesis of celiac disease. By contrast, the PT digests from monoccum wheat (Triticum monococcum) and farro wheat (T. turgidum ssp. dicoccum) did not exhibit any negative effects on Caco-2/TC7 and K562(S) cells.
European Journal of Nutrition, 2010
Purpose Celiac disease (CD) is a permanent intolerance to wheat prolamins and related proteins displayed by genetically susceptible individuals. Blocking or modulation of CD-specific T cell response by altered prolamin peptides are currently considered as a potential alternative to the only effective therapy of CD based on a life-long glutenfree diet. Two prolamin peptides, the 9-mer ASRVAPGQQ and the 10-mer GTVGVAPGQQ sequences, were identified by mass spectrometry in the peptic/tryptic digest of prolamins (PTP) from durum wheat (Triticum turgidum ssp. durum) cv. Adamello, and investigated for their ability to preclude the stimulation of CD-specific mucosal T cells by gluten proteins. Methods Gluten-specific polyclonal intestinal T cell lines from five CD children (mean age 5 years) were exposed to 50 lg/ml of a deamidated PTP from whole flour of common wheat (T. aestivum) cv. San Pastore, and tested for proliferation and production of interferon-c (INF-c) and interleukin 10 (IL-10). The same experiment was performed in the presence of 20 lg/ml of the 9-mer or the 10-mer peptide. Results T cells exposed to PTP showed a threefold increase in proliferation and INF-c production, and a significant (P B 0.05) reduction in IL-10 secretion as compared with control cells incubated with the culture medium. Addition of either the 9-mer or the 10-mer peptide to PTP downregulated T cell proliferation and INF-c production, and caused a significant (P B 0.05) increase in IL-10 secretion.
Analytical and Bioanalytical Chemistry, 2009
Celiac disease (CD) is a permanent gastrointestinal disorder characterized by the intolerance to a group of proteins called gluten present in wheat, rye, barley, and possibly oats. The only therapy is a strict lifelong glutenfree diet. The standard method for gluten determination in foods produced for CD patients is the R5-enzyme-linked immunosorbent assay (ELISA) as proposed by the recent Codex Alimentarius Draft Revised Standard. This test is based on the determination of prolamins, the alcoholsoluble proteins of gluten, and is available as a sandwich ELISA for intact proteins and as a competitive ELISA for gluten-derived peptides. While the suitability of the sandwich ELISA including a wheat prolamin (gliadin) reference for calibration has been shown by various studies and a ring test, the competitive ELISA still lacks a convenient reference for the quantitation of gluten peptides in fermented cereal foods (e.g., sourdough products, starch syrup, malt extracts, beer). Therefore, the aim of the present study was to prepare a suitable reference for the quantitation of partially hydrolyzed gluten in fermented wheat, rye, and barley products. The prolamin fractions from barley (hordein) and rye (secalin) were isolated from corresponding flours by means of a modified preparative Osborne fractionation. The prolamin fraction from wheat was obtained as reference gliadin from the Prolamin Working Group. The prolamin fractions were successively digested by pepsin and trypsin or pepsin and chymotrypsin procedures, which have been used for CD-specific toxicity Keywords Celiac disease. Gluten-free diet. Gluten content. ELISA Abbreviations CD Celiac disease ELISA Enzyme-linked immunosorbent assay HMM High molecular mass HPLC High-performance liquid chromatography LOD Limit of detection LOQ Limit of quantitation M r Molecular mass (relative)
Molecular Breeding, 2018
Wheat proteins are important for the physicochemical properties of bread-dough and contribute to the protein intake in the human diet. In certain individuals, an immunological reactivity of the gluten protein family is strongly implicated in the etiology of celiac disease (CD) and non-celiac wheat sensitivity (NCWS). There is evidence that gluten-related disorders have increased in frequency in recent years. Gluten proteins were characterized and quantified by reversed-phase high-performance liquid chromatography (RP-HPLC) while the occurrence of CD immunogenic epitopes was searched in the gliadin sequences of Triticeae within the NCBI database. We have observed a tendency toward low content of gliadins in cultivated species compared to that of the wild ancestors in all Triticeae members. Regarding the glutenin subunits, there was no clear trend, but levels tended to be higher in cultivated species. Thousand-kernel weight is higher for domesticated and cultivated species. Quantification of DQ2and DQ8-restricted epitopes in gliadin sequences showed a great variability in the number of CD epitopes per species and genome. A higher frequency of immunnogenic epitopes was found to be associated with genomes of the DD, BBAADD, and RR type. Durum wheats tend to have a lower content of gluten and CD immunogenic epitopes. Cultivated barley could be an alternative cereal with low immunogenic epitopes and low gluten. The results reported in this study suggest that domestication and breeding have contributed to a decrease in the content of gliadins and total gluten in the Triticeae species over time.
Nutrients
The wheat varietal selection undertaken by breeders in recent decades has been tailored mainly to improve technological and productivity-related traits; however, the latter has resulted in a considerable impoverishment of the genetic diversity of wheat-based products available on the market. This pitfall has encouraged researchers to revalue the natural diversity of cultivated and non-cultivated wheat genotypes in light of their different toxic/immunogenic potential for celiac disease and wheat-allergic patients. In the present investigation, an advanced proteomic approach was designed for the global characterization of the protein profile of selected tetraploid wheat genotypes (Triticum turgidum). The approach combined proteins/peptides sequence information retrieved by specific enzymatic digestions (single and dual proteolytic enzymes) with protein digestibility information disclosed by means of in-vitro simulated human gastroduodenal digestion experiments. In both cases, the pept...
Spanish Journal of Agricultural Research, 2008
The allelic variation at seven prolamin loci involved in quality has been studied in a set of durum wheat landraces from all the Spanish regions where this crop has been traditionally cultivated. The genetic variability was higher than that found in other germplasm collections. All the loci, except Glu-B2, displayed a genetic variability higher than 0.62, with Glu-3 the most polymorphic. In total, five alleles were studied at Glu-A1, nine at Glu-B1, 15 at Glu-A3, 18 at Glu-B3, two at Glu-B2, and eight at Gli-A1 and Gli-B1. New allelic variants not previously identified in durum wheat were detected. The 30 different genotypes of B low-molecular-weight (B-LMW) glutenin subunits analysed, of which 25 are novel, provide an important source of genetic variability for quality breeding. Protein patterns for convars. durum and turgidum, and for the North and South of Spain were identified for the loci with significant influence on quality. Higher variability was observed in convar. turgidum and in the North zone than in convar. durum and the South, respectively, mainly for the Glu-B1 and Glu-B3. Also, convar. turgidum appeared to be a valuable source for new alleles for the LMW glutenin subunits. Wheats from the South were, however, more diverse for prolamins encoded at Glu-A3.
Gluten Free Wheat (Triticum Aestivum L.): A Genetic Way to Curb Coeliac Disease
Journal of Advanced Scientific Research
There are three main cereal crops, rice, maize and wheat, in which, latter constitutes the major portion in the category. According to 2017 reports, it is known to be harvested around 772 million tonnes. Wheat is present in a diverse range and gets its elasticity, viscosity and properties of binding by the storage protein, Gluten, which is a secretory protein synthesised on rough endoplasmic reticulum. Gluten is roughly 78-85% of total wheat protein and made of gliadin and glutenins. There is a part of population with genes which develop autoimmune response against gluten that majorly affects the small intestine by damaging its lining and have to suffer from problems like pain in abdomen, joints, anaemia, osteoporosis and various gastro intestinal problems, developmental problems and problems like cramping, itching and lactose tolerance and excess weight loss. The patients who suffer from this disease undergo either biopsy of small intestine or serological assay like Rapid or ELISA ...
Gluten proteins, namely gliadins, are the primary trigger of the abnormal immune response in celiac disease. It has been hypothesised that modern wheat breeding practices may have contributed to the increase in celiac disease prevalence during the latter half of the 20th century. Our results do not support this hypothesis as Triticum aestivum spp. vulgare landraces, which were not subjected to breeding practices , presented higher amounts of potential celiac disease's immunostimulatory epitopes when compared to modern varieties. Furthermore, high variation between wheat varieties concerning the toxic epitopes amount was observed. We carried out quantitative analysis of gliadin types by RP-HPLC to verify its correlation with the amount of toxic epitopes: x-type gliadins content explain about 40% of the variation of toxic epitopes in tetraploid wheat varieties. This research provides new insights regarding wheat toxicity and into the controversial idea that human practices may have conducted to an increased exposure to toxic epitopes.