Can Celiac Disease Be Prevented?

Celiac disease (CD) is an autoimmune disorder triggered by gluten in genetically susceptible individuals characterized by a variable combination of gluten-dependent symptoms, presence of specific autoantibodies and enteropathy. The health burden of CD is considerable, as it reduces quality of life  and, at a societal level, has extensive negative economic consequences. Prevention strategies are based on the identification of at-risk subjects and identification and elimination of risk factors. A number of prospective observational and interventional studies conducted on the general population, and more often in subjects at-risk, have given important information on the natural history of the disease. Both genetic and environmental factors have been identified with the former, in particular histocompatibility genes, playing a major role. Environmental factors, some operating already before birth, have been identified, with feeding pattern in the first year of life (breast feeding, amount and time of introduction of gluten) and infections being the most relevant. Prospective studies have also allowed the identification of biomarkers predictive of the disease which in perspective could better define the population on which to intervene. Interventions have been so far limited to modifications of feeding patterns. However, as also learnt from diseases that share with CD genetic risk factors and mechanisms of damage, such as type 1 diabetes (T1D), future strategies may be envisaged based on protection from infections, manipulation of microbiota, intervention on T cells.

Measures of gluten-related reactivity in children with autism spectrum disorders in the absence of overt gastrointestinal symptoms: a pilot study from the United Arab Emirates

Objectives

The aetiology of autism spectrum disorder (ASD) is multifactorial, sometimes genetic, and may be associated with abnormal immunological responses to peptides from proteins such as gluten. These peptides may cross the blood-brain barrier and affect neurotransmission, resulting in behavioural symptoms consistent with ASD. The aim of this study was to screen for markers of gluten-related immune reactivity in the absence of overt gastrointestinal symptoms in patients with ASD in the United Arab Emirates, a country associated with a high prevalence of ASD but lacking this type of research.

Methods

Patients diagnosed with ASD (using Diagnostic and Statistical Manual of Mental Disorders-IV-based criteria and Autism Diagnostic Observational Schedules) were compared with controls, regarding anti-tissue transglutaminase (tTG) immunoglobulin (Ig) A and anti-deamidated gliadin peptide (DGP) IgA levels.

Results

Sixty-six patients with ASD and 101 controls were included. Patients with ASD showed statistically significant lower anti-DGP IgA levels, but no significant difference in anti-tTG IgA levels, versus healthy controls. Correlations between immunological data and clinical symptoms were synergistic, but not statistically significant.

Conclusion

ASD may be associated with reduced levels of anti-DGP IgA.

Stability of the human gut virome and effect of gluten-free diet

The human gut microbiome consists of bacteria, archaea, eukaryotes, and viruses. The gut viruses are relatively underexplored. Here, we longitudinally analyzed the gut virome composition in 11 healthy adults: its stability, variation, and the effect of a gluten-free diet. Using viral enrichment and a de novo assembly-based approach, we demonstrate the quantitative dynamics of the gut virome, including dsDNA, ssDNA, dsRNA, and ssRNA viruses. We observe highly divergent individual viral communities, carrying on an average 2,143 viral genomes, 13.1% of which were present at all 3 time points. In contrast to previous reports, the Siphoviridae family dominates over Microviridae in studied individual viromes. We also show individual viromes to be stable at the family level but to vary substantially at the genera and species levels. Finally, we demonstrate that lower initial diversity of the human gut virome leads to a more pronounced effect of the dietary intervention on its composition.

The α-Gliadins in Bread Wheat: Effect of Nitrogen Treatment on the Expression of the Major Celiac Disease Immunogenic Complex in Two RNAi Low-Gliadin Lines

Celiac Disease (CD) is an autoimmune disorder that affects approximately 1% of the worldwide population. The α-gliadins of wheat contain the 33-mer peptide, the most active peptide in CD both in adults and pediatric patients. In this study, we have characterized the variants and expression profile of an α-gliadins amplicon, harboring the 33-mer peptide, in two low-gliadin RNAi wheat lines, under two different Nitrogen (N) treatments. We estimated that the amplicon expands 45 different α-gliadin variants with high variability due to length, randomly distributed SNPs, and the presence of encoded CD epitopes. Expression of this amplicon is reduced in both RNAi lines in comparison to the wild type. High N treatment significantly increases transcripts of the amplicon in the wild type, but not in the transgenic lines. Classification of α-gliadin variants, considering the number of epitopes, revealed that amplicon variants containing the full complement of 33-mer peptide were affected by N treatment, increasing their expression when N was increased. Line D793 provided higher and more stable silencing through different N fertilization regimes, expressing fewer CD epitopes than D783. Results of this study are important for better understanding of RNAi α-gliadin silencing in response to N treatments, and for undertaking new strategies by RNAi or CRISPR/Cas toward obtaining new varieties suitable for people suffering gluten intolerances.

Diagnosis of coeliac disease by flow cytometry of intraepithelial lymphocytes: a new 'gold' standard?

OBJECTIVE

The analysis of intraepithelial lymphocytes (IELs) by flow cytometry of duodenal biopsies-the 'IEL' lymphogram-has been proposed as a diagnostic test for coeliac disease. However, its clinical applicability has been limited due to variability in methods and definitions. This study set out to define useful parameters for the application of the IEL lymphogram to the diagnosis of coeliac disease.

DESIGN

Flow cytometry was performed on 117 sets of duodenal biopsies in 107 adult patients with active coeliac disease, long-term coeliac disease on a gluten free diet and a control group. The initial 95 samples were used for hypothesis generation for the subsequent samples comprising 12 patients with coeliac disease and 10 controls.

RESULTS

Rather than using single linear cut-offs for CD3 and T-cell receptor γδ (TCRγδ)+ve IELs, a discriminant function was identified as %CD3+ve IELs+2x(%TCRγδ+IELs)>100. This differentiated coeliac disease from control biopsies in the hypothesis generating group. These results were replicated in the validation group and found to be independent of histology in patients on long-term gluten free diet up to 12 years (combined sensitivity, 98.5%; specificity, 97.7%).

CONCLUSIONS

Flow cytometric analysis of IELs is a highly sensitive and specific adjunct to serology and histological examination for the diagnosis of coeliac disease, even in individuals with coeliac disease following a gluten free diet who exhibit normal duodenal histology.

Coffee Cherry Pulp by-Product as a Potential Fiber Source for Bread Production: A Fundamental and Empirical Rheological Approach

Effects of substituting of wheat flour with coffee cherry pulp powder (CCPP) (coffee by-product as fiber source) at 0, 1.2, 2.3, and 4.7% dry basis (0, 1.25, 2.5, and 5% wet basis) on dough and gluten rheological properties and baking quality were investigated. Rheological properties were analyzed during mixing, compression recovery, and creep-recovery. A rheological approach was adopted to study the viscoelasticity of dough enriched with fiber. The data obtained were analyzed with the Kelvin-Voigt model and the parameters were correlated to bread volume and crumb firmness to assess the effect of incorporating CCPP. A decrease in gluten's elastic properties was attributed to the water-binding and gelling properties of CCPP. Stiffness of dough and crumb firmness increased as the level of CCPP increased and bread volume decreased. Stiffer dough corresponded with lower compliance values and higher steady state viscosity compared to the control. A follow-up study with 5% CCPP and additives is recommended to overcome the reduction in elastic recovery and bread volume.

Exploring the alpha-gliadin locus: the 33-mer peptide with six overlapping coeliac disease epitopes in Triticum aestivum is derived from a subgroup of Aegilops tauschii

Most alpha-gliadin genes of the Gli-D2 locus on the D genome of hexaploid bread wheat (Triticum aestivum) encode for proteins with epitopes that can trigger coeliac disease (CD), and several contain a 33-mer peptide with six partly overlapping copies of three epitopes, which is regarded as a remarkably potent T-cell stimulator. To increase genetic diversity in the D genome, synthetic hexaploid wheat lines are being made by hybridising accessions of Triticum turgidum (AB genome) and Aegilops tauschii (the progenitor of the D genome). The diversity of alpha-gliadins in A. tauschii has not been studied extensively. We analysed the alpha-gliadin transcriptome of 51 A. tauschii accessions representative of the diversity in A. tauschii. We extracted RNA from developing seeds and performed 454 amplicon sequencing of the first part of the alpha-gliadin genes. The expression profile of allelic variants of the alpha-gliadins was different between accessions, and also between accessions of the Western and Eastern clades of A. tauschii. Generally, both clades expressed many allelic variants not found in bread wheat. In contrast to earlier studies, we detected the 33-mer peptide in some A. tauschii accessions, indicating that it was introduced along with the D genome into bread wheat. In these accessions, transcripts with the 33-mer peptide were present at lower frequencies than in bread wheat varieties. In most A. tauschii accessions, however, the alpha-gliadins do not contain the epitope, and this may be exploited, through synthetic hexaploid wheats, to breed bread wheat varieties with fewer or no coeliac disease epitopes.

Interactions between dietary fiber and ferulic acid change the aggregation of glutenin, gliadin and glutenin macropolymer in wheat flour system

BACKGROUND

Glutenin macropolymer (GMP), glutenin and gliadin proteins are important indicators of the baking quality of dough. This study investigated the impacts of wheat bran and a mixture of ferulic acid (FA) and dietary fiber (DF) on the constitution of gluten proteins. Addition of wheat bran (100 and 150 g kg^-1 ) into gluten decreased the gliadin/glutenin ratio, while the addition of different amounts of FA + DF (C1 group: 20 g kg^-1 FA and 60 g kg^-1 DF; C2 group: 30 g kg^-1 FA and 90 g kg^-1 DF) had the opposite effect.

RESULTS

The GMP contents of wheat bran groups (B1 group: 100 g kg^-1 ; B2 group: 150 g kg^-1 ) were similar to that of the control group, and disulfide bond contents were increased. However, both GMP and disulfide bond contents of FA + DF groups significantly decreased. The GMP gel properties and microstructures were destroyed after addition of wheat bran and FA + DF. The wheat bran and FA + DF additives induced different effects on the thermal properties and secondary structures of glutenin, gliadin and GMP.

CONCLUSIONS

The results suggest that the interaction mechanism of bran fractions and gluten proteins is not only related to the physicochemical properties of the additives, but also to interactions between the additives and the components of gluten protein. © 2020 Society of Chemical Industry.

"Let Food Be Thy Medicine": Gluten and Potential Role in Neurodegeneration

Wheat is a most favored staple food worldwide and its major protein is gluten. It is involved in several gluten dependent diseases and lately was suggested to play a role in non-celiac autoimmune diseases. Its involvement in neurodegenerative conditions was recently suggested but no cause-and-effect relationship were established. The present narrative review expands on various aspects of the gluten-gut-brain axes events, mechanisms and pathways that connect wheat and gluten consumption to neurodegenerative disease. Gluten induced dysbiosis, increased intestinal permeabillity, enteric and systemic side effects, cross-reactive antibodies, and the sequence of homologies between brain antigens and gluten are highlighted. This combination may suggest molecular mimicry, alluding to some autoimmune aspects between gluten and neurodegenerative disease. The proverb of Hippocrates coined in 400 BC, "let food be thy medicine," is critically discussed in the frame of gluten and potential neurodegeneration evolvement.

Gluten-Free Foods Cooked in Shared Fryers With Wheat: A Pilot Study Assessing Gluten Cross Contact

Introduction: Consumers with celiac disease are discouraged from eating fried foods cooked in shared fryers with wheat-containing foods at restaurants based on presumed gluten exposure. The purpose of the present study is to assess gluten levels of fries free of gluten-containing ingredients cooked in shared fryers with wheat.

Methods: 20 orders of fries were purchased from 10 different restaurants. Restaurants confirmed that fries and oil were free of gluten-containing ingredients. All restaurants confirmed that their fryers were used to cook wheat-containing foods. Fries were sent to Bia Diagnostics and tested in 1-gram duplicates using the R7001 sandwich R5 ELISA and the R7021 competitive R5 ELISA. A microwave control also was run.

Results: The sandwich ELISA found gluten in 9/20 fry orders (7 to > 80 ppm). The competitive ELISA found gluten in 3/20 fry orders (14 to > 270 ppm). In the microwave control (60-ppm gluten mixture of wheat flour and canola oil), the unheated mixture tested at a mean level of 64 ppm gluten using the sandwich ELISA and 137 ppm gluten using the competitive ELISA. The mixture heated to 190°C tested at a mean level of 55 ppm gluten using the sandwich ELISA and < 10 ppm and 16 ppm gluten using the competitive ELISA.

Discussion: Based on test results, 25% of fry orders would not be considered gluten-free.

Summary: Gluten cross contact may occur when gluten-free foods are cooked in shared fryers with wheat. ELISAs may underperform when analyzing for gluten that has been heated.

Human leukocyte antigen (HLA)-DQ2 and -DQ8 haplotypes in celiac, celiac with type 1 diabetic, and celiac suspected pediatric cases

Celiac disease (CD) is an autoimmune enteropathy triggered by ingestion of gluten present in wheat, barley, and rye. Gluten along with environmental trigger starts an inflammatory reaction which results in damage to small intestine. Human leukocyte antigen (HLA)-DQA1∗05, -DQB1∗02, and -DQB1∗03:02 are the known risk alleles of CD. The diagnostic method for CD involves serological or intestinal biopsy, but genetic test could be implemented. HLA typing precludes the need for further diagnosis and it has high negative predictive value. The aim of this study was to make aware of HLA molecular typing for celiac disease among local laboratories and healthcare professionals. The prevalence and frequency distribution of HLA-DQ2 and -DQ8 haplotypes in 175 pediatric unrelated healthy controls, celiac patients, and CD with concurrent diabetes mellitus type 1 (DM1) was evaluated. The most common haplotype was DQ2 followed by DQ8. In control group only DQ2 was observed with frequency of 8.5%. In celiac patients 85.7% were DQ2, 11.4% were DQ8, and rest were DQ2/DQ8 (2.8%), and all had CD. In the group of CD with DM1, 31.4% had DQ2, 25% had DQ8, and 34% having both the haplotypes; while only 9 of these patients were suffering from CD. It was concluded that Celiac disease is frequently unrecognized by physicians, in part because of its variable clinical presentation and symptoms. Thus genetic testing for celiac disease could be an additive tool for diagnosis to exclude ambiguity.

Frequency of Gluten-Reactive T Cells in Active Celiac Lesions Estimated by Direct Cell Cloning

Chronic inflammation of the small intestine in celiac disease is driven by activation of CD4+ T cells that recognize gluten peptides presented by disease-associated HLA-DQ molecules. We have performed direct cell cloning of duodenal biopsies from five untreated and one refractory celiac disease patients, and three non-celiac disease control subjects in order to assess, in an unbiased fashion, the frequency of gluten-reactive T cells in the disease-affected tissue as well as the antigen fine specificity of the responding T cells. From the biopsies of active disease lesions of five patients, 19 T-cell clones were found to be gluten-reactive out of total 1,379 clones tested. This gave an average of 1.4% (range 0.7% - 1.9%) of gluten-reactive T cells in lamina propria of active celiac lesions. Interestingly, also the patient with refractory celiac disease had gluten-reactive T cell clones in the lamina propria (5/273; 1.8%). In comparison, we found no gluten-reactive T cells in any of the total 984 T-cell clones screened from biopsies from three disease control donors. Around two thirds of the gluten-reactive clones were reactive to a panel of peptides representing known gluten T-cell epitopes, of which two thirds were reactive to the immunodominant DQ2.5-glia-α1/DQ2.5-glia-α2 and DQ2.5-glia-ω1/DQ2.5-glia-ω2 epitopes. This study shows that gluten-reactive T cells in the inflamed duodenal tissue are prevalent in the active disease lesion, and that many of these T cells are reactive to T-cell epitopes that are not yet characterized. Knowledge of the prevalence and epitope specificity of gluten-specific T cells is a prerequisite for therapeutic efforts that target disease-specific T cells in celiac disease.

Gluten Intake and All-Cause and Cause-Specific Mortality: Prospective Findings from the UK Biobank

BACKGROUND

Gluten has been linked to adverse effects on metabolic and vascular health.

OBJECTIVES

The present study determines the association between dietary gluten intake and all-cause (primary objective), as well as cause-specific, mortality in people without celiac disease.

METHODS

Gluten intake was estimated in 159,265 participants of the UK Biobank which is a large multicenter, prospective cohort study initiated in 2006. Cox proportional hazard regression models were used and HRs were determined for all-cause and cause-specific mortality. All models were adjusted for confounders and multiple testing.

RESULTS

Median (IQR) age was 57 (49-62) y with 52.1% of participants being female. Gluten intake was 8.5 (5.1-12.4) g/d with significantly higher consumption in males [10.0 (6.3-14.1) g/d] than in females [7.2 (4.6-10.7) g/d] (P < 0.0001). During a median follow-up of 11.1 (10.6-11.9) y and 1.8 million person-years, 6259 deaths occurred. Gluten intake was not significantly associated with all-cause mortality after adjusting for confounders (HR: 1.00; 95% CI: 1.00, 1.01; P = 0.59). Dietary gluten was not significantly associated with cancer (HR: 1.00; 95% CI: 1.00, 1.01; raw P = 0.24) or noncancer (HR: 1.00; 95% CI: 0.99, 1.01; raw P = 0.56) mortality. However, gluten intake was positively associated with ischemic heart disease mortality (HR: 1.02; 95% CI: 1.01, 1.04; raw P = 0.003, Holm-adjusted P = 0.04).

CONCLUSIONS

Gluten intake is not significantly associated with all-cause and cancer mortality in adults without celiac disease. The findings support the hypothesis that limiting gluten intake is unlikely to provide significant overall survival benefits on a population level. The positive association between gluten intake and ischemic heart disease mortality requires further study.

Epitope mapping of anti-amelogenin IgG in untreated celiac children

Children with untreated celiac disease (CeD) may develop enamel defects, and children with severe CeD have significantly increased levels of IgG to amelogenin, which may interfere with normal amelogenesis depending on which epitope(s) they bind. Children with untreated CeD (n = 42), for whom CeD had been confirmed either by biopsy (n = 17, cohort 1) or by the presence of particularly high serum levels of anti-transglutaminase 2 (TG2) IgA (n = 25, cohort 2), were selected from 146 children with CeD, and 10 controls were selected from 34 children who did not have CeD. Samples from these 52 children were used for detailed IgG anti-amelogenin, X isoform (AMELX) epitope mapping using 31 overlapping, 10-22mer peptides in ELISA. Although sera from both groups showed reactivity to peptides containing sequences from the N and C terminus of AMELX, sera from children with CeD reacted more strongly to peptides from the central region (amino acids 75-150) containing both a binding site for transforming growth factor-β (TGF-β), as well as the enzymatic cleavage sites for matrix metalloproteinase-20 and for kallikrein-4. Antigen-specific extraction revealed that only IgG to the central region cross-reacted to gliadin. Thus, cross-reactive anti-gliadin/amelogenin IgG may affect normal amelogenesis by interfering with enzymatic degradation, proper folding, and/or TGF-β signaling in children with untreated CeD.

The use of peripheral blood mononuclear cells in celiac disease diagnosis and treatment

Introduction: Celiac disease is characterized by an abnormal immune activation driven by the ingestion of gluten from wheat, barley, and rye. Gluten-specific CD4⁺ T cells play an important role in disease pathogenesis and are detectable among peripheral blood mononuclear cells (PBMCs). Areas covered: This review summarizes the use of celiac disease patient PBMCs in clinical applications focusing on their exploitation in the development of diagnostic approaches and novel drugs to replace or complement gluten-free diet. Expert opinion: The most used PBMC-based methods applied in celiac disease research include ELISpot and HLA-DQ:gluten tetramer technology. ELISpot has been utilized particularly in research aiming to develop a celiac disease vaccine and in studies addressing the toxicity of different grains in celiac disease. HLA-DQ:gluten tetramer technology on the other hand initially focused on improving current diagnostics but in combination with additional markers it is also a useful outcome measure in clinical trials to monitor the efficacy of drug candidates. In addition, the technology serves well in the more detailed characterization of celiac disease-specific T cells, thereby possibly revealing novel therapeutic targets. Future studies may also reveal clinical applications for PBMC microRNAs and/or dendritic cells or monocytes present among PBMCs.

The addition of alpha amylase improves the quality of Chinese dried noodles

The effect of α-amylase on the quality attributes of Chinese dried noodles (CDN) was investigated. Adding α-amylase markedly decreased the cooking time and cooking loss of CDN at the level of 12.5 (mg/100 g flour). The elasticity of CDN was increased significantly (P < 0.05) after adding α-amylase. The firmness of noodles with 12.5 mg α-amylase per 100 g flour showed no obvious change compared to the control, whereas it decreased significantly (P < 0.05) when the amount of α-amylase increased to 25 (mg/100 g flour). In addition, the chewiness of CDN with 12.5 mg α-amylase per 100 g flour increased, while it showed a significant (P < 0.05) decreasing trend with further increased α-amylase levels. Starch structural and thermal properties were also changed by α-amylase, which showed increased relative crystallinity, swelling power, but decreased pasting property. The changed starch property restrained the cross-linking of gluten. The decrease in optimal cooking time and increase in elasticity of CDN were due to the increased swelling power and decreased peak time of the starch. In addition, the decreased setback of starch and protein cross-linking degree were responsible for the decreased firmness and chewiness of CDN with α-amylase ranging from 25 to 50 mg/100 g flour. Overall, α-amylase could be used as a functional additive to improve the quality of CDN when the amount was at 12.5 mg/100 g flour.

An updated overview on celiac disease: from immuno-pathogenesis and immuno-genetics to therapeutic implications

INTRODUCTION

Celiac disease (CD) is an autoimmune enteropathy triggered by ingestion of gluten. While presenting many similarities with other autoimmune diseases, celiac disease is unique in that the external trigger, gluten, and the genetic background necessary for disease development (HLA DQ2/DQ8) are well described. The prevalence of celiac disease is dramatically increasing over the years and new epidemiologic data show changes regarding age of onset and symptoms. A better understanding of CD-pathogenesis is fundamental to highlight the reasons of this rise of celiac diagnoses.

AREAS COVERED

In this review we describe CD-pathogenesis by dissecting all the components necessary to lose tolerance to gluten (ingestion of gluten, genetic predisposition, loss of barrier function and immune response). Additionally, we also highlight the role that microbiome plays in celiac disease as well as new proposed therapies and experimental tools.

EXPERT OPINION

Prevalence of autoimmune diseases is increasing around the world. As a result, modern society is strongly impacted by a social and economic burden. Given the unique characteristics of celiac disease, a better understanding of its pathogenesis and the factors that contribute to it may shed light on other autoimmune diseases for which external trigger and genetic background are not known.

Effects of Physical and Chemical Factors on the Structure of Gluten, Gliadins and Glutenins as Studied with Spectroscopic Methods

This review presents applications of spectroscopic methods, infrared and Raman spectroscopies in the studies of the structure of gluten network and gluten proteins (gliadins and glutenins). Both methods provide complimentary information on the secondary and tertiary structure of the proteins including analysis of amide I and III bands, conformation of disulphide bridges, behaviour of tyrosine and tryptophan residues, and water populations. Changes in the gluten structure can be studied as an effect of dough mixing in different conditions (e.g., hydration level, temperature), dough freezing and frozen storage as well as addition of different compounds to the dough (e.g., dough improvers, dietary fibre preparations, polysaccharides and polyphenols). Additionally, effect of above mentioned factors can be determined in a common wheat dough, model dough (prepared from reconstituted flour containing only wheat starch and wheat gluten), gluten dough (lack of starch), and in gliadins and glutenins. The samples were studied in the hydrated state, in the form of powder, film or in solution. Analysis of the studies presented in this review indicates that an adequate amount of water is a critical factor affecting gluten structure.

Differences in Processing Quality Traits, Protein Content and Composition between Spelt and Bread Wheat Genotypes Grown under Conventional and Organic Production

The unique rheological properties of bread wheat dough and the breadmaking quality of its flour are the main factors responsible for the global distribution and utilization of wheat. Recently, interest in the production and expansion of spelt wheat has been boosted due to its significance in the production of healthy food, mostly originated from organic production. The aim of this study was to examine and compare quality parameters (gluten content, Zeleny sedimentation volume, farinograph dough properties), protein content and composition (by the Dumas method, Size Exclusion (SE) and Reversed Phase (RP) High Performance Liquid Chromatography (HPLC) analyses) of five bread and five spelt wheat varieties grown under conventional and organic production in Hungary and under conventional production in Serbia. Most of the analyzed traits showed significant differences between varieties, wheat species and growing sites. Total protein content was significantly higher in spelt than in bread wheat and under conventional than under organic production. In comparison to spelt, bread wheat showed better breadmaking quality, characterized by a higher amount of glutenins (in particular high molecular weight glutenin subunits) and unextractable polymeric proteins. The proportion of the gliadins was also found to be different under conventional and organic systems. Spelt Ostro and Oberkulmer-Rotkorn and bread wheat varieties Balkan, Estevan and Pobeda proved suitable for low input and organic systems.

Methods for the Modification and Evaluation of Cereal Proteins for the Substitution of Wheat Gluten in Dough Systems

The substitution of wheat gluten in the food industry is a relevant research area because the only known treatment for celiac disease is abstinence from this protein complex. The use of gluten-free cereals in dough systems has demonstrated that the viscoelastic properties of gluten cannot be achieved without the modification of the protein fraction. The quality of the final product is determined by the ability of the modification to form a matrix similar to that of gluten and to reach this, different methods have been proposed and tested. These procedures can be classified into four main types: chemical, enzymatic, physical, and genetic. This article provides a comprehensive review of the most recent research done in protein modification of cereal and pseudocereals for gluten substitution. The reported effects and methodologies for studying the changes made with each type of modification are described; also, some opportunity areas for future works regarding the study of the effect of protein modifications on gluten-free products are presented.

Gliadin Sequestration as a Novel Therapy for Celiac Disease: A Prospective Application for Polyphenols

Celiac disease is an autoimmune disorder characterized by a heightened immune response to gluten proteins in the diet, leading to gastrointestinal symptoms and mucosal damage localized to the small intestine. Despite its prevalence, the only treatment currently available for celiac disease is complete avoidance of gluten proteins in the diet. Ongoing clinical trials have focused on targeting the immune response or gluten proteins through methods such as immunosuppression, enhanced protein degradation and protein sequestration. Recent studies suggest that polyphenols may elicit protective effects within the celiac disease milieu by disrupting the enzymatic hydrolysis of gluten proteins, sequestering gluten proteins from recognition by critical receptors in pathogenesis and exerting anti-inflammatory effects on the system as a whole. This review highlights mechanisms by which polyphenols can protect against celiac disease, takes a critical look at recent works and outlines future applications for this potential treatment method.

Classification of intestinal T-cell receptor repertoires using machine learning methods can identify patients with coeliac disease regardless of dietary gluten status

In coeliac disease (CeD), immune-mediated small intestinal damage is precipitated by gluten, leading to variable symptoms and complications, occasionally including aggressive T-cell lymphoma. Diagnosis, based primarily on histopathological examination of duodenal biopsies, is confounded by poor concordance between pathologists and minimal histological abnormality if insufficient gluten is consumed. CeD pathogenesis involves both CD4⁺ T-cell-mediated gluten recognition and CD8⁺ and γδ T-cell-mediated inflammation, with a previous study demonstrating a permanent change in γδ T-cell populations in CeD. We leveraged this understanding and explored the diagnostic utility of bulk T-cell receptor (TCR) sequencing in assessing duodenal biopsies in CeD. Genomic DNA extracted from duodenal biopsies underwent sequencing for TCR-δ (TRD) (CeD, n = 11; non-CeD, n = 11) and TCR-γ (TRG) (CeD, n = 33; non-CeD, n = 21). We developed a novel machine learning-based analysis of the TCR repertoire, clustering samples by diagnosis. Leave-one-out cross-validation (LOOCV) was performed to validate the classification algorithm. Using TRD repertoire, 100% (22/22) of duodenal biopsies were correctly classified, with a LOOCV accuracy of 91%. Using TCR-γ (TRG) repertoire, 94.4% (51/54) of duodenal biopsies were correctly classified, with LOOCV of 87%. Duodenal biopsy TRG repertoire analysis permitted accurate classification of biopsies from patients with CeD following a strict gluten-free diet for at least 6 months, who would be misclassified by current tests. This result reflects permanent changes to the duodenal γδ TCR repertoire in CeD, even in the absence of gluten consumption. Our method could complement or replace histopathological diagnosis in CeD and might have particular clinical utility in the diagnostic testing of patients unable to tolerate dietary gluten, and for assessing duodenal biopsies with equivocal features. This approach is generalisable to any TCR/BCR locus and any sequencing platform, with potential to predict diagnosis or prognosis in conditions mediated or modulated by the adaptive immune response. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Do gastroenterologists have medical inertia towards coeliac disease? A UK multicentre secondary care study

OBJECTIVE

This study aimed to assess if there is secondary care medical inertia towards coeliac disease (CD).

DESIGN

Group (1): Time from primary care presentation to diagnostic endoscopy was quantified in 151 adult patients with a positive endomysial antibody test and compared with 92 adult patients with histologically proven inflammatory bowel disease (IBD). Group (2): Across four hospitals, duodenal biopsy reports for suspected CD were reviewed (n=1423). Group (3): Clinical complexity was compared between known CD (n=102) and IBD (n=99) patients at their respective follow-up clinic appointments. Group (4): 50 gastroenterologists were questioned about their perspective on CD and IBD.

RESULTS

Group (1): Suspected coeliac patients waited significantly longer for diagnostic endoscopy following referral (48.5 (28-89) days) than suspected patients with IBD (34.5 (18-70) days; p=0.003). Group (2): 1423 patients underwent diagnostic endoscopy for possible CD, with only 40.0% meeting guidelines to take four biopsies. Increased diagnosis of CD occurred if guidelines were followed (10.1% vs 4.6% p<0.0001). 12.4% of newly diagnosed CD patients had at least one non-diagnostic gastroscopy in the 5 years prior to diagnosis. Group (4): 32.0% of gastroenterologists failed to identify that CD has greater prevalence in adults than IBD. Moreover, 36.0% of gastroenterologists felt that doctors were not required for the management of CD.

CONCLUSION

Prolonged waiting times for endoscopy and inadequacies in biopsy technique were demonstrated suggesting medical inertia towards CD. However, this has to be balanced against rationalising care accordingly. A Coeliac UK National Patient Charter may standardise care across the UK.