Innate and adaptive immunity: the yin and yang of celiac disease

The association of gluten-free diet with thyroid autoimmunity in patients with celiac disease: a meta-analysis

Background: Thyroid autoimmunity is an immune response to thyroid antigens that causes varying degrees of thyroid dysfunction. The sole effective treatment for Celiac Disease (CD) is a gluten-free diet (GFD). However, the association between GFD and thyroid autoimmunity in patients with CD has not been confirmed. Methods: A comprehensive search of several databases, involving PubMed, Embase, Web of Science, Medline, and Cochrane databases, was conducted to identify studies that primarily addressed the effects of GFD on thyroid autoimmunity in CD subjects. The meta-analysis involved studies that compared the risk of ATPO and ATG antibody positivity in CD patients with GFD, the risk of developing AITD, and the risk of developing thyroid dysfunction. Fixed-effects models or random-effects models were used to calculate the odds ratios (ORs) and their 95% confidence intervals (95% CIs). Results: A total of 10 observational studies met the inclusion criteria and included 6423 subjects. The results indicated that GFD is positively associated with thyroid autoimmunity in the children subgroup of CD patients (OR = 1.61, 95%CI 1.06-2.43, P = 0.02). However, there was no significant difference in thyroid autoimmunity between the group adhering to GFD and the control group in the total CD population. Conclusion: The results seem to indicate that subjects with a more pronounced autoimmunity (such as to have an early onset of CD) appear to have a greater risk of thyroid autoimmunity.

Inflammatory auto-immune diseases of the intestine and their management by natural bioactive compounds

Autoimmune diseases are caused by the overactivity of the immune system towards self-constituents. Risk factors of autoimmune diseases are multiple and include genetic, epigenetic, environmental, and psychological. Autoimmune chronic inflammatory bowel diseases, including celiac and inflammatory diseases (Crohn's disease and ulcerative colitis), constitute a significant health problem worldwide. Besides the complexity of the symptoms of these diseases, their treatments have only been palliative. Numerous investigations showed that natural phytochemicals could be promising strategies to fight against these autoimmune diseases. In this respect, plant-derived natural compounds such as flavonoids, phenolic acids, and terpenoids exhibited significant effects against three autoimmune diseases affecting the intestine, particularly bowel diseases. This review focuses on the role of natural compounds obtained from medicinal plants in modulating inflammatory auto-immune diseases of the intestine. It covers the most recent literature related to the effect of these natural compounds in the treatment and prevention of auto-immune diseases of the intestine.

Biomarkers to Monitor Adherence to Gluten-Free Diet by Celiac Disease Patients: Gluten Immunogenic Peptides and Urinary miRNAs

Celiac disease (CD) is a multifactorial autoimmune enteropathy with a prevalence greater than 1% in the pediatric population. The only therapy for CD patients is a strict gluten-free diet (GFD). Gluten-free food contamination by other cereals during packaging and cooking or accidental ingestion of gluten may cause several intestinal and extraintestinal symptoms in CD patients. Therefore, the monitoring of gluten contamination in food and assessing the level of ingested gluten by analytical biomarkers has been of great interest in recent years. To this aim, small gluten immunogenic peptides (GIPs) obtained by the hydrolysis of gluten and present in urine and feces have been studied as biomarkers of gluten intake and to monitor adherence to GFD by CD patients. More recently, the use of circulating, fecal and urinary miRNAs has emerged as a novel diagnostic tool that can be potentially applied to assess adherence to GFD. Moreover, the presence of GIPs and miRNAs in both feces and urine suggests a similar excretion modality and the possibility of using urinary miRNAs, similarly to GIPs, as potential biomarkers of GFD in CD patients.

Rapid spectroscopic method for quantifying gluten concentration as a potential biomarker to test adulteration of green banana flour

The demand for gluten-free banana flour has led manufactures to enforce strict measures for quality control. A need has arisen for the development of more sensitive and reliable methods to test the quality of green banana flour (GBF). The objective of this study was to develop rapid visible to near-infrared (Vis-NIR) based spectroscopic models to detect gluten concentration, as a biomarker to detect wheat flour adulteration in green banana flour (GBF). Spectroscopic data were acquired using a desktop (FOSS®) Vis-NIR spectroscopy ranging from 400 to 2500 nm of the electromagnetic spectrum. The spectral and reference data were submitted to principal component analysis (PCA) and partial least squares regression (PLSR) for the development of gluten adulteration detection models. Calibration models were constructed based on a full cross-validation approach, consisting of 51 samples for the calibration set and 21 samples for the test set. PCA scores plot discriminated gluten adulterated and unadulterated GBF samples with 100% accuracy for the first two principal components (PCs). The optimal prediction model was obtained after a combination of baseline (offset and baseline linear correlation) and standard normal variate (SNV) pre-processing technique. This model showed a 94% coefficient of determination of cross-validation (R²_cv) and prediction (R²_p); root mean square error of cross-validation (RMSECV) of 3.7 mg/kg, root mean square error of prediction (RMSEP) of 3.9 mg/kg; and RPD value of 4. This work has demonstrated that Vis-NIRS method is a robust and feasible technology that may be used to ensure the safety of banana flour and that this product stays gluten-free by providing good and reliable gluten detection and quantification prediction models.

Microbiome signatures of progression toward celiac disease onset in at-risk children in a longitudinal prospective cohort study

Other than exposure to gluten and genetic compatibility, the gut microbiome has been suggested to be involved in celiac disease (CD) pathogenesis by mediating interactions between gluten/environmental factors and the host immune system. However, to establish disease progression markers, it is essential to assess alterations in the gut microbiota before disease onset. Here, a prospective metagenomic analysis of the gut microbiota of infants at risk of CD was done to track shifts in the microbiota before CD development. We performed cross-sectional and longitudinal analyses of gut microbiota, functional pathways, and metabolites, starting from 18 mo before CD onset, in 10 infants who developed CD and 10 matched nonaffected infants. Cross-sectional analysis at CD onset identified altered abundance of six microbial strains and several metabolites between cases and controls but no change in microbial species or pathway abundance. Conversely, results of longitudinal analysis revealed several microbial species/strains/pathways/metabolites occurring in increased abundance and detected before CD onset. These had previously been linked to autoimmune and inflammatory conditions (e.g., Dialister invisus, Parabacteroides sp., Lachnospiraceae, tryptophan metabolism, and metabolites serine and threonine). Others occurred in decreased abundance before CD onset and are known to have anti-inflammatory effects (e.g., Streptococcus thermophilus, Faecalibacterium prausnitzii, and Clostridium clostridioforme). Additionally, we uncovered previously unreported microbes/pathways/metabolites (e.g., Porphyromonas sp., high mannose-type N-glycan biosynthesis, and serine) that point to CD-specific biomarkers. Our study establishes a road map for prospective longitudinal study designs to better understand the role of gut microbiota in disease pathogenesis and therapeutic targets to reestablish tolerance and/or prevent autoimmunity.

Contribution of Infectious Agents to the Development of Celiac Disease

The ingestion of wheat gliadin (alcohol-soluble proteins, an integral part of wheat gluten) and related proteins induce, in genetically predisposed individuals, celiac disease (CD), which is characterized by immune-mediated impairment of the small intestinal mucosa. The lifelong omission of gluten and related grain proteins, i.e., a gluten-free diet (GFD), is at present the only therapy for CD. Although a GFD usually reduces CD symptoms, it does not entirely restore the small intestinal mucosa to a fully healthy state. Recently, the participation of microbial components in pathogenetic mechanisms of celiac disease was suggested. The present review provides information on infectious diseases associated with CD and the putative role of infections in CD development. Moreover, the involvement of the microbiota as a factor contributing to pathological changes in the intestine is discussed. Attention is paid to the mechanisms by which microbes and their components affect mucosal immunity, including tolerance to food antigens. Modulation of microbiota composition and function and the potential beneficial effects of probiotics in celiac disease are discussed.

Suppressed immune profile in children with combined type 1 diabetes and celiac disease

Children diagnosed with a combination of type 1 diabetes (T1D) and celiac disease (CD) show a dysregulated T helper type 1 (Th1)/Th17 response. Besides the cellular involvement, several soluble immune markers are involved in the autoimmune process of both T1D and CD. Only few studies have examined the peripheral pattern of different cytokines, chemokines and acute-phase proteins (APP) in children with combined T1D and CD. To our knowledge, no studies have evaluated the serum levels of adipocytokines and matrix metalloproteinases (MMPs) in this context. The purpose of the present study was to acquire more knowledge and to gain deeper understanding regarding the peripheral immunoregulatory milieu in children with both T1D and CD. The study included children diagnosed with both T1D and CD (n = 18), children with T1D (n = 27) or CD (n = 16) and reference children (n = 42). Sera were collected and analysis of 28 immune markers (cytokines, chemokines, APPs, adipocytokines and MMPs) was performed using the Luminex technique. The major findings showed that children with a double diagnosis had lower serum levels of interleukin (IL)-22, monocyte chemoattractant protein (MIP)-1α, monocyte chemoattractant protein (MCP)-1, procalcitonin, fibrinogen, visfatin and matrix metalloproteinase (MMP)-2. These results indicate a suppressed immune profile in children with combined T1D and CD, including Th17 cytokines, chemokines, APPs, adipocytokines and MMPs. We conclude that, besides cytokines and chemokines, other immune markers, e.g. APPs, adipocytokines and MMPs, are of importance for further investigations to elucidate the heterogeneous immune processes present in patients diagnosed with T1D in combination with CD.

RNA sequencing of intestinal mucosa reveals novel pathways functionally linked to celiac disease pathogenesis

BACKGROUND & AIMS

The early steps in the pathophysiology of celiac disease (CD) leading to loss of tolerance to gluten are poorly described. Our aim was to use RNA sequencing of duodenal biopsies in patients with active CD, CD in remission, and non-CD controls to gain insight into CD pathophysiology, identify additional genetic signatures linked to CD, and possibly uncover targets for future therapeutic agents.

METHODS

We performed whole transcriptome shotgun sequencing of intestinal biopsies in subjects with active and remission CD and non-CD controls. We also performed functional pathway analysis of differentially expressed genes to identify statistically significant pathways that are up or down regulated in subjects with active CD compared to remission CD.

RESULTS

We identified the upregulation of novel genes including IL12R, ITGAM and IGSF4 involved in the immune response machinery and cell adhesion process in the mucosa of subjects with active CD compared to those in remission. We identified a unique signature of genes, related to innate immunity, perturbed exclusively in CD irrespective of disease status. Finally, we highlight novel pathways of interest that may contribute to the early steps of CD pathogenesis and its comorbidities such as the spliceosome, pathways related to the innate immune response, and pathways related to autoimmunity.

CONCLUSIONS

Our study confirmed previous findings based on GWAS and immunological studies pertinent to CD pathogenesis and describes novel genes and pathways that with further validation may be found to contribute to the early steps in the pathogenesis of CD, ongoing inflammation, and comorbidities associated with CD.

Nutritional composition of gluten-free food versus regular food sold in the Italian market

BACKGROUND

Some concerns have been raised about the nutritional composition of gluten-free (GF) food.

AIM

To compare the nutritional composition of GF food with regular foods.

METHODS

This study examined in total 235 GF products and 349 regular products purchased in Italy, from seven categories: biscuits, rusks, snacks, bread, pasta, bread substitutes and wheat flour. The following nutritional facts, have been considered: energy, proteins, total and saturated fats, carbohydrates, simple sugars, fibers and salt. The mean nutrient composition for products of the two groups was compared by independent samples t-test.

RESULTS

The protein content of GF food is lower in all the categories (P < 0.001). s. Total energy was lower for GF bread (P < 0.001) and higher for GF pasta (P = 0.05). GF biscuits and pasta had higher saturated fats content (P < 0.001 and P = 0.003). No difference was seen for total fat. Sugar content was lower for GF pasta (P < 0.001). Fiber content was lower in GF biscuits, bread substitutes (P < 0.001) and pasta (P = 0.02), higher in bread (P = 0.03). Salt content was higher in GF pasta (P < 0.001) and rusks (P = 0.04), lower in biscuits (P < 0.001).

CONCLUSIONS

There are some differences in the nutritional composition of GF food and regular food. These differences should be taken into account when planning a balanced GF diet.

Celiac Disease Autoimmunity

Celiac disease is an autoimmune condition triggered by the ingestion of gluten, the protein fraction of wheat, barley and rye. It is not simply an intestinal disease; it is multifactorial caused by many different genetic factors acting together with non-genetic causes. Similar to other autoimmune diseases, celiac disease is a polygenic disorder for which the major histocompatibility complex locus is the most important genetic factor, and is the result of an immune response to self-antigens leading to tissue destruction and the autoantibodies production. Celiac disease exemplifies how an illness can have autoimmune-like features having to be driven by exogenous antigen and how can be reasonably considered as a model of organ-specific autoimmunity.

Autoantibodies in the Extraintestinal Manifestations of Celiac Disease

Increased antibody reactivity towards self-antigens is often indicative of a disruption of homeostatic immune pathways in the body. In celiac disease, an autoimmune enteropathy triggered by the ingestion of gluten from wheat and related cereals in genetically predisposed individuals, autoantibody reactivity to transglutaminase 2 is reflective of the pathogenic role of the enzyme in driving the associated inflammatory immune response. Autoantibody reactivity to transglutaminase 2 closely corresponds with the gluten intake and clinical presentation in affected patients, serving as a highly useful biomarker in the diagnosis of celiac disease. In addition to gastrointestinal symptoms, celiac disease is associated with a number of extraintestinal manifestations, including those affecting skin, bones, and the nervous system. Investigations of these manifestations in celiac disease have identified a number of associated immune abnormalities, including B cell reactivity towards various autoantigens, such as transglutaminase 3, transglutaminase 6, synapsin I, gangliosides, and collagen. Clinical relevance, pathogenic potential, mechanism of development, and diagnostic and prognostic value of the various identified autoantibody reactivities continue to be subjects of investigation and will be reviewed here.

New coeliac disease treatments and their complications

The only accepted treatment for coeliac disease is strict adherence to a gluten-free diet. This type of diet may give rise to reduced patient quality of life with economic and social repercussions. For this reason, dietary transgressions are common and may elicit intestinal damage. Several treatments aimed at different pathogenic targets of coeliac disease have been developed in recent years: modification of gluten to produce non-immunogenic gluten, endoluminal therapies to degrade gluten in the intestinal lumen, increased gluten tolerance, modulation of intestinal permeability and regulation of the adaptive immune response. This review evaluates these coeliac disease treatment lines that are being researched and the treatments that aim to control disease complications like refractory coeliac disease.

Gluten peptides drive healthy and celiac monocytes toward an M2-like polarization

Celiac disease (CD) is an immune-mediated enteropathy triggered by ingested gluten in genetically susceptible individuals and sustained by both adaptive and innate immune responses. Recent studies in murine macrophages demonstrated that the activation of arginase (ARG) metabolic pathway by gluten peptides contributes to the modulation of intestinal permeability in vitro. Here we characterize the effects of gluten on arginine metabolism and cell polarization in human monocytes from both healthy and CD subjects; both a simplified enzymatic digestion of gliadin and a physiological digestion of whole wheat have been tested. Results indicate that gluten digests induce the onset of an M2-like phenotype in activated macrophages; more precisely, both isoforms of arginase, ARG1 and ARG2, are induced likely due to the inhibition of mTOR and the consequent induction of C/EBPβ transcription factor. These effects are independent from the origin of gluten as well as from the digestive protocol employed; moreover, no statistical difference can be evidenced between healthy and CD patients, excluding a diverse predisposition of CD monocytes to gluten-triggered polarization with respect to healthy immune cells. Overall, the present findings sustain a role for arginase pathway in the immune response elicited by human monocytes toward ingested gluten that, hence, deserves particular attention when addressing the pathogenesis of CD.

A review on the relationship between gluten and schizophrenia: Is gluten the cause?

INTRODUCTION

Schizophrenia is a chronic disease that possesses various clinical manifestations. It presents rather heterogeneous characteristics with respect to onset type, symptoms, and the course of the disease. Although the lifetime prevalence is as low as 1%, it can cause serious disability. Thus, it is very important to develop efficient treatment methods. In some studies, it is hypothesized that removing gluten from the diet leads to a significant improvement in disease symptoms. Epidemiological studies revealed that the prevalence of celiac disease among schizophrenic patients is almost two times higher than that of the general population.

OBJECTIVE

In this review, we evaluate the effects of gluten and celiac disease on the onset of schizophrenia. Efficacy of gluten-free diet applications, antibody response against gluten, and the interaction of the brain-gut axis and the presence of common genetic points are also investigated.

METHODS

Without any publication date restriction, Pubmed database searches were made for 'schizophrenia, gluten, gliadin, celiac disease, exorphin, brain-gut axis, psychiatric disorders.' The keywords and the articles about the schizophrenia-celiac disease relationship are included in our review.

RESULTS

Several studies presented evidence to suggest that symptoms associated with schizophrenia were minimized when gluten was excluded from patients' diets. Immunological searches revealed that most schizophrenic patients with increased anti-gliadin antibodies did not possess celiac disease; yet, the presence of increased antibodies against gliadin can be the share point of the immunological abnormalities found in both of the diseases.

DISCUSSION

There were no consistent results in the clinical, immunological, microbiological, and epidemiological studies that investigated the relationship between schizophrenia and celiac disease. This presents a need for a larger scale study to confirm the presence of this suggested correlation between schizophrenia and celiac disease. The underlying mechanisms between the two diseases should be explored.

Redox signaling in the gastrointestinal tract

Redox signaling regulates physiological self-renewal, proliferation, migration and differentiation in gastrointestinal epithelium by modulating Wnt/β-catenin and Notch signaling pathways mainly through NADPH oxidases (NOXs). In the intestine, intracellular and extracellular thiol redox status modulates the proliferative potential of epithelial cells. Furthermore, commensal bacteria contribute to intestine epithelial homeostasis through NOX1- and dual oxidase 2-derived reactive oxygen species (ROS). The loss of redox homeostasis is involved in the pathogenesis and development of a wide diversity of gastrointestinal disorders, such as Barrett's esophagus, esophageal adenocarcinoma, peptic ulcer, gastric cancer, ischemic intestinal injury, celiac disease, inflammatory bowel disease and colorectal cancer. The overproduction of superoxide anion together with inactivation of superoxide dismutase are involved in the pathogenesis of Barrett's esophagus and its transformation to adenocarcinoma. In Helicobacter pylori-induced peptic ulcer, oxidative stress derived from the leukocyte infiltrate and NOX1 aggravates mucosal damage, especially in HspB+ strains that downregulate Nrf2. In celiac disease, oxidative stress mediates most of the cytotoxic effects induced by gluten peptides and increases transglutaminase levels, whereas nitrosative stress contributes to the impairment of tight junctions. Progression of inflammatory bowel disease relies on the balance between pro-inflammatory redox-sensitive pathways, such as NLRP3 inflammasome and NF-κB, and the adaptive up-regulation of Mn superoxide dismutase and glutathione peroxidase 2. In colorectal cancer, redox signaling exhibits two Janus faces: On the one hand, NOX1 up-regulation and derived hydrogen peroxide enhance Wnt/β-catenin and Notch proliferating pathways; on the other hand, ROS may disrupt tumor progression through different pro-apoptotic mechanisms. In conclusion, redox signaling plays a critical role in the physiology and pathophysiology of gastrointestinal tract.

Why Oats Are Safe and Healthy for Celiac Disease Patients

The water-insoluble storage proteins of cereals (prolamins) are called “gluten” in wheat, barley, and rye, and “avenins” in oat. Gluten can provoke celiac disease (CD) in genetically susceptible individuals (those with human leukocyte antigen (HLA)-DQ2 or HLA-DQ8 serotypes). Avenins are present at a lower concentration (10%–15% of total protein content) in oat as compared to gluten in wheat (80%–85%). The avenins in the genus Avena (cultivated oat as well as various wild species of which gene bank accessions were analyzed) are free of the known CD immunogenic epitopes from wheat, barley, and rye. T cells that recognize avenin-specific epitopes have been found very rarely in CD patients. CD patients that consume oats daily do not show significantly increased levels of intraepithelial lymphocyte (EIL) cells. The safety and the positive health effects of the long-term inclusion of oats in the gluten-free diet have been confirmed in long-term studies. Since 2009 (EC 41/2009) and 2013 (FDA) oat products may be sold as gluten-free in several countries provided a gluten contamination level below 20 ppm. Introduction of oats in the gluten-free diet of celiac patients is advised after the recovery of the intestine. Health effects of oat consumption are reflected in European Food Safety Authority (EFSA)- and Food and Drug Administration (FDA)-approved health claims. Oats can form a healthy, nutritious, fiber-rich, and safe complement to the gluten-free diet.

Treatment of allergic rhinitis with acupoint herbal plaster: an oligonucleotide chip analysis

Background

Allergic rhinitis is regarded as an imbalanced Th1/Th2 cell-mediated response. The present study used microarray analysis to compare gene expression levels between allergic rhinitis patients before and after a series of acupoint herbal plaster applications.

Methods

In this experimental pilot study, volunteers experiencing sneezing, runny nose, and congestion for more than 9 months in the year following initial diagnoses were included after diagnostic confirmation by otolaryngologists to exclude patients with sinusitis and nasal polyps. Patients with persistent allergic rhinitis each received four acupoint herbal plaster treatments applied using the moxibustion technique. Clinical outcomes were evaluated using the Rhinitis Quality of Life Questionnaire (RQLQ). Peripheral blood samples were analyzed using an ImmunoCAP Phadiatop test, and patients were classified as phadiatop (Ph)-positive or -negative. Microarray results were analyzed for genes that were differentially expressed between (1) Ph-positive and -negative patients treated with herbal plaster; and (2) before and after herbal plaster treatment in the Ph-positive patient group. Unsupervised and supervised methods were used for gene-expression data analysis.

Results

Nineteen Ph-positive and four Ph-negative participants with persistent allergic rhinitis were included in the study. RQLQ results indicated that the 19 Ph-positive volunteers experienced improvement in six of seven categories following acupoint herbal plaster treatments, whereas the four Ph-negative participants reported improvement in only two categories. Hierarchical clustering and principle component analysis of the gene expression profiles of Ph-positive and –negative participants indicated the groups exhibited distinct physiological responses to acupoint herbal treatment. Evaluation of gene networks using MetaCore identified that the “Immune response_IL-13 signaling via JAK-STAT” and the “Inflammation_Interferon signaling” were down- and up-regulated, respectively, among Ph-positive subjects.

Conclusions

In this preliminary study, we find that the IL-13 immune response via JAK-STAT signaling and interferon inflammation signaling were down- and upregulated, respectively, in the Ph-positive group. Further studies are required to verify these pathways in Ph-positive patients, and to determine the mechanism of such pathway dysregulation.

Trial registration

ClinicalTrials.gov: NCT02486159. Registered 30 Jun 2015.

Risk of Cross-Contact for Gluten-Free Pizzas in Shared-Production Restaurants in Relation to Oven Cooking Procedures

To allow celiac patients to have meals out, a growing number of restaurants and pizzas houses that simultaneously provide gluten-free (GF) pizzas and wheat-based (WB) pizzas have recently been opened in Italy. In these restaurants, GF pizzas are prepared with GF raw materials, following procedures that minimize the risk of gluten cross-contact. Here, we evaluate the risk of gluten cross-contact of GF pizzas in relation to the preparation procedures, thus aiming at identifying a safe procedure for cooking GF pizzas. Our results show that, when specific requirements are complied with, the simultaneous cooking of GF and WB pizzas is a procedure as safe as having an oven dedicated to GF pizzas or the alternate cooking of GF and WB pizzas in the same oven.

Gluten-free diet does not influence the occurrence and the Th1/Th17-Th2 nature of immune-mediated diseases in patients with coeliac disease

INTRODUCTION

Coeliac disease (CD) is the most common Th1-mediated enteropathy, frequently associated with other immune-mediated disorders (IMD).

AIMS

To evaluate: (1) the prevalence of IMD at the time of and after CD diagnosis; (2) a possible change in immune response to gluten free diet (GFD); (3) the potential role of GFD in reducing and/or preventing IMD in CD.

METHODS

Prospective study including all consecutive adult CD patients who underwent investigations for Th1-Th17/Th2-IMD at the time of CD diagnosis and after a 5-year follow-up period.

RESULTS

1255 CD were enrolled. Of these, 257 patients (20.5%) showed IMD at the time of CD diagnosis, with 58.4% presenting a Th1/Th17-IMD. After a 5-year follow-up period, 682 patients (54.3%) showed new IMD despite GFD. Of these, 57.3% presented a Th1/Th17-IMD and 42.7% a Th2-IMD (p=0.8). When compared the prevalence of each type of IMD before and after CD diagnosis, we did not identify any significant "switch" from Th1/Th17- to Th2-IMD or vice versa. The number of patients with Th1/Th17- and/or Th2-IMD increased during the GFD period (20.5% vs 54.3%; p<0.01; OR 1.9).

CONCLUSIONS

The prevalence of IMD at the time of CD diagnosis is high and it seems to increase in the follow-up period despite GFD.

Infant feeding and risk of developing celiac disease: a systematic review

OBJECTIVE

To review the evidence for the association of breast feeding, breastfeeding duration or the timing of gluten introduction and the later development of celiac disease (CD).

DESIGN

Systematic review.

METHODS

We searched MEDLINE, via PubMed, EMBASE and Web of Science, for studies published up to 31 August 2015 investigating the association of breastfeeding duration, breast feeding at the moment of gluten introduction or the timing of gluten introduction and the later development of CD. Prospective studies had to enrol infants/children at high risk of CD. For retrospective studies, participants had to be children or adults with CD. The paper quality was assessed by means of a GRADE score and the bias risk was assessed by the Newcastle-Ottawa Scale (for observational cohort studies) and Cochrane Collaboration's tool (for randomised trials).

RESULTS

Out of 149 retrieved papers, 48 were considered in depth and 16 were included in this review (9 were prospective and 2 were interventional). We found that neither duration of breastfeeding nor breastfeeding at time of gluten introduction nor the delayed introduction of gluten during weaning were effective in preventing later development of CD.

CONCLUSIONS

Currently, there is no evidence on the optimal breastfeeding duration or the effects of avoiding early (<4 months of age) or late (≥ 6 or even at 12 months) gluten introduction in children at risk of CD. Accordingly, no specific general recommendations about gluten introduction or optimal breastfeeding duration can be presently provided on evidence-based criteria in order to prevent CD.

Novel avian single-chain fragment variable (scFv) targets dietary gluten and related natural grain prolamins, toxic entities of celiac disease

BACKGROUND

Celiac disease (CD) is a chronic, small intestinal inflammatory disease mediated by dietary gluten and related prolamins. The only current therapeutic option is maintenance of a strict life-long gluten-free diet, which implies substantial burden for CD patients. Different treatment regimes might be feasible, including masking of toxic celiac peptides with blocking antibodies or fragments thereof. The objective of this study was therefore to select and produce a recombinant avian single-chain fragment variable (scFv) directed against peptic-tryptic digested gliadin (PT-Gliadin) and related celiac toxic entities.

RESULTS

Gluten-free raised chicken of same age were immunized with PT-Gliadin. Chicken splenic lymphocytes, selected with antigen-coated magnetic beads, served as RNA source for the generation of cDNA. Chicken VH and VL genes were amplified from the cDNA by PCR to generate full-length scFv constructs consisting of VH and VL fragments joined by a linker sequence. ScFv constructs were ligated in a prokaryotic expression vector, which provides a C-terminal hexahistidine tag. ScFvs from several bacterial clones were expressed in soluble form and crude cell lysates screened for binding to PT-Gliadin by ELISA. We identified an enriched scFv motif, which showed reactivity to PT-Gliadin. One selected scFv candidate was expressed and purified to homogeneity. Polyclonal anti-PT-Gliadin IgY, purified from egg yolk of immunized chicken, served as control. ScFv binds in a dose-dependent manner to PT-Gliadin, comparable to IgY. Furthermore, IgY competitively displaces scFv from PT-Gliadin and natural wheat flour digest, indicating a common epitope of scFv and IgY. ScFv was tested for reactivity to different gastric digested dietary grain flours. ScFv detects common and khorasan wheat comparably with binding affinities in the high nanomolar range, while rye is detected to a lesser extent. Notably, barley and cereals which are part of the gluten-free diet, like corn and rice, are not detected by scFv. Similarly, the pseudo-grain amaranth, used as gluten-free alternative, is not targeted by scFv. This data indicate that scFv specifically recognizes toxic cereal peptides relevant in CD.

CONCLUSION

ScFv can be of benefit for future CD treatment regimes.

Distal duodenum versus duodenal bulb: intraepithelial lymphocytes have something to say in celiac disease diagnosis

BACKGROUND AND AIM

After clinical screening and the serological test, many patients still require a duodenal biopsy for celiac disease diagnosis. Mild histological lesions, unspecific findings and patchiness are frequent outcomes of this mandatory diagnostic tool, thus complicating clinical decisions.

METHODS

We analyzed the lymphoid components [number of total intraepithelial lymphocytes (IELs), TcR-γδ and CD3(-)IELs] of the duodenal epithelium by flow cytometry in samples obtained from bulb and distal duodenum during upper gastrointestinal endoscopies performed for diagnostic purposes.

RESULTS

IEL counts and IEL subset distribution (IEL lymphogram) remain invariant along duodenal mucosa revealing a specific profile (immunophenotype) that characterizes either a healthy mucosa or a celiac mucosa. The celiac immunophenotype persists regardless of the biopsy's anatomical location or the corresponding histological findings.

CONCLUSIONS

We propose the IEL lymphogram by flow cytometry as an immunological parameter to discern celiac condition from healthy mucosa. This obviates not only misinterpretation of minor histological changes, but also patchiness and the concerns about the location and number of biopsies.

Gliadin-dependent cytokine production in a bidimensional cellular model of celiac intestinal mucosa

The downstream cascade of the inflammatory response to gliadin in celiac intestinal mucosa encompasses the early activation of the innate immunity that triggers the adaptive response. Therefore, the in vitro study of the pathogenic mechanism of celiac disease (CD) on enterocytes alone or mucosal T lymphocytes alone does not fully consider all the aspects of gliadin-dependent inflammation. Although the in vitro culture of specimens of intestinal mucosa obtained from celiac patients is the gold standard for the study of CD, this technique presents several technical challenges and the bioptic specimens are not easily available. So, in this paper, we described the gliadin-dependent cytokine production in a bidimensional cellular system, which is able to mimic both the innate and the adaptive steps of the mucosal immune response of CD. In the upper compartment, the intestinal epithelial cells are grown on a filter, and in the lower compartment, the mononuclear cells isolated from peripheral blood of celiac patients are cultured. Cells were apically exposed to the toxic gliadin peptide p31-43 for 3 h and then with the immunodominant gliadin fragment pα-9 for 21 h. The incubation with gliadin peptides resulted in increased levels of IL-15, INF-γ, IL-6, tumor necrosis factor (TNF)-α, IL-1β, and CCL 2, 3 and 4 in the basal supernatants, with respect to cells exposed to medium alone. The p31-43-driven epithelial priming of mucosal response consists of transglutaminase (TG2)-mediated deamidation of the immunostimulatory gliadin peptides, as demonstrated by the inhibition of pα-9 activity, when the system is exposed to blocking anti-TG2 antibody.

Involvement of heat shock proteins in gluten-sensitive enteropathy

Gluten-sensitive enteropathy, also known as coeliac disease (CD), is an autoimmune disorder occurring in genetically susceptible individuals that damages the small intestine and interferes with the absorption of other nutrients. As it is triggered by dietary gluten and related prolamins present in wheat, rye and barley, the accepted treatment for CD is a strict gluten-free diet. However, a complete exclusion of gluten-containing cereals from the diet is often difficult, and new therapeutic strategies are urgently needed. A class of proteins that have already emerged as drug targets for other autoimmune diseases are the heat shock proteins (HSPs), which are highly conserved stress-induced chaperones that protect cells against harmful extracellular factors. HSPs are expressed in several tissues, including the gastrointestinal tract, and their levels are significantly increased under stress circumstances. HSPs exert immunomodulatory effects, and also play a crucial role in the maintenance of epithelial cell structure and function, as they are responsible for adequate protein folding, influence the degradation of proteins and cell repair processes after damage, and modulate cell signalling, cell proliferation and apoptosis. The present review discusses the involvement of HSPs in the pathophysiology of CD. Furthermore, HSPs may represent a useful therapeutic target for the treatment of CD due to the cytoprotective, immunomodulatory, and anti-apoptotic effects in the intestinal mucosal barrier.

Diversity of oat varieties in eliciting the early inflammatory events in celiac disease

Purpose

Celiac disease (CD) is an autoimmune enteropathy, triggered by dietary gluten. The only treatment is a strict gluten-free diet. Oats are included in the list of gluten-free ingredients by European Regulation, but the safety of oats in CD is still a matter of debate. The present study examined the capability of different oat cultivars of activating the gliadin-induced transglutaminase-2 (TG2)-dependent events in some in vitro models of CD. In addition, we compared this capability with the electrophoresis pattern of peptic–tryptic digests of the proteins of the oat cultivars.

Methods

K562(S) cells agglutination, transepithelial electrical resistance of T84-cell monolayers, intracellular levels of TG2 and phosphorylated form of protein 42–44 in T84 cells were the early gliadin-dependent events studied.

Results

The results showed that the Nave oat cultivar elicited these events, whereas Irina and Potenza varieties did not. The ability of a cultivar to activate the above-described events was associated with the electrophoretic pattern of oat proteins and their reactivity to anti-gliadin antibodies.

Conclusion

We found significant differences among oat cultivars in eliciting the TG2-mediated events of CD inflammation. Therefore, the safety of an oat cultivar in CD might be screened in vitro by means of biochemical and biological assays, before starting a clinical trial to definitely assess its safety.

Pathogen-specific risk of celiac disease following bacterial causes of foodborne illness: a retrospective cohort study

BACKGROUND

The US CDC recently estimated over 2 million foodborne illnesses annually are caused by 4 major enteropathogens: non-typhoid Salmonella spp., Campylobacter spp., Shigella spp., and Yersinia enterocolitica. While recent data suggest functional gastrointestinal disorders are associated with these infections, studies linking foodborne illness to celiac disease (CD) are limited. We utilized a US Department of Defense medical encounter database to evaluate the risk of CD following select foodborne infections.

METHODS

We identified subjects with acute gastroenteritis between 1998 and 2009 attributed to Salmonella (nontyphoidal) spp., Shigella spp., Campylobacter spp., or Y. enterocolitica and matched each with up to 4 unexposed subjects. Exposed and unexposed subjects were followed for incident CD diagnosis for their entire military record duration (or a minimum of 1 year). Relative risks were calculated using modified Poisson regression to determine the relationship between pathogen-attributable gastroenteritis and CD while controlling for covariates.

RESULTS

A total of 1,753 pathogen-specific gastroenteritis cases (Campylobacter: 738; Salmonella: 624; Shigella: 376; Yersinia: 17) were identified and followed for a median of 3.8 years. The incidence (per 100,000 person-years) of CD was 0.05. We found a suggested risk of CD after Campylobacter, but not other foodborne infection etiologies.

CONCLUSIONS

These data support a previous study demonstrating increased risk of CD following Campylobacteriosis and highlight the need for additional research into how infections might trigger CD in susceptible individuals.

Markers of Celiac Disease and Gluten Sensitivity in Children with Autism

OBJECTIVE

Gastrointestinal symptoms are a common feature in children with autism, drawing attention to a potential association with celiac disease or gluten sensitivity. However, studies to date regarding the immune response to gluten in autism and its association with celiac disease have been inconsistent. The aim of this study was to assess immune reactivity to gluten in pediatric patients diagnosed with autism according to strict criteria and to evaluate the potential link between autism and celiac disease.

METHODS

Study participants included children (with or without gastrointestinal symptoms) diagnosed with autism according to both the Autism Diagnostic Observation Schedule (ADOS) and the Autism Diagnostic Interview, Revised (ADI-R) (n = 37), their unaffected siblings (n = 27), and age-matched healthy controls (n = 76). Serum specimens were tested for antibodies to native gliadin, deamidated gliadin, and transglutaminase 2 (TG2). Affected children were genotyped for celiac disease associated HLA-DQ2 and -DQ8 alleles.

RESULTS

Children with autism had significantly higher levels of IgG antibody to gliadin compared with unrelated healthy controls (p<0.01). The IgG levels were also higher compared to the unaffected siblings, but did not reach statistical significance. The IgG anti-gliadin antibody response was significantly greater in the autistic children with gastrointestinal symptoms in comparison to those without them (p<0.01). There was no difference in IgA response to gliadin across groups. The levels of celiac disease-specific serologic markers, i.e., antibodies to deamidated gliadin and TG2, did not differ between patients and controls. An association between increased anti-gliadin antibody and presence of HLA-DQ2 and/or -DQ8 was not observed.

CONCLUSIONS

A subset of children with autism displays increased immune reactivity to gluten, the mechanism of which appears to be distinct from that in celiac disease. The increased anti-gliadin antibody response and its association with GI symptoms points to a potential mechanism involving immunologic and/or intestinal permeability abnormalities in affected children.

Dietary proteins and functional gastrointestinal disorders

Food intolerance is a common complaint amongst patients with functional gastrointestinal (GI) disorders (FGIDs), including those with irritable bowel syndrome (IBS), functional dyspepsia, as well as gastroesophageal reflux disease. Although there has been a longstanding interest in the possible role of food allergy in IBS, there are limited data supporting the association. However, the prevalence of food allergy is sufficiently high that patients with FGID may also have food allergies or hypersensitivities. Food intolerances or sensitivities are reactions to foods, which are not due to immunological mechanisms. Lactose intolerance is common in the general population and can mimic symptoms of FGID or coexist with FGID. As discussed in other articles in this series, other carbohydrate intolerances may be responsible for symptom generation in patients with IBS and perhaps other FGIDs. There is a great interest in the role of a major dietary protein, gluten, in the production of symptoms that are very similar to those of patients with celiac disease without the enteropathy that characterizes celiac disease. Emerging research into a syndrome known as nonceliac gluten sensitivity suggests a heterogeneous condition with some features of celiac disease but often categorized as FGIDs, including IBS. This article summarizes the role of dietary proteins in the symptoms and pathophysiology of FGIDs.

Gluten-sensitive enteropathy coincides with decreased capability of intestinal T cells to secrete IL-17 and IL-22 in a macaque model for celiac disease

Celiac disease (CD) is an autoimmune disorder caused by intolerance to dietary gluten. The interleukin (IL)-17 and IL-22 function as innate regulators of mucosal integrity. Impaired but not well-understood kinetics of the IL-17/22 secretion was described in celiac patients. Here, the IL-17 and IL-22-producing intestinal cells were studied upon their in vitro stimulation with mitogens in class II major histocompatibility complex-defined, gluten-sensitive rhesus macaques. Pediatric biopsies were collected from distal duodenum during the stages of disease remission and relapse. Regardless of dietary gluten content, IL-17 and IL-22-producing cells consisted of CD4+ and CD8+ T lymphocytes as well as of lineage-negative (Lin-) cells. Upon introduction of dietary gluten, capability of intestinal T cells to secrete IL-17/22 started to decline (p<0.05), which was paralleled with gradual disruption of epithelial integrity. These data indicate that IL-17/22-producing cells play an important role in maintenance of intestinal mucosa in gluten-sensitive primates.

Farinin: characterization of a novel wheat endosperm protein belonging to the prolamin superfamily

Starch granule surface-associated proteins were separated by HPLC and identified by direct protein sequencing. Among the proteins identified was one that consisted of two polypeptide chains of 11 and 19 kDa linked by disulfide bonds. Sequencing of tryptic peptides from each of the polypeptides revealed similarities between some of the peptides and avenin-like b proteins encoded by partial cDNAs in NCBI. To identify a contiguous sequence that matched all of the peptides, contigs encoding three avenin-like b proteins were constructed from ESTs of the cultivar Butte 86. All peptide sequences were found in a protein encoded by one of these contigs that had not been identified previously. Protein and DNA sequences indicated that the two polypeptide chains were derived from a parent protein that had been cleaved at the C-terminal position of an asparagine residue. The name farinin is suggested for this protein and other avenin-like b proteins. Evolutionary relationships of the protein are discussed and a simple computer molecular model was constructed. On the basis of its sequence, the new protein was likely to be allergenic but unlikely to be active in celiac disease.

A randomized, double-blind study of larazotide acetate to prevent the activation of celiac disease during gluten challenge

OBJECTIVES

In patients with celiac disease, enteropathy is caused by the entry of gluten peptides into the lamina propria of the intestine, in which their immunogenicity is potentiated by tissue transglutaminase (tTG) and T-helper type 1-mediated immune responses are triggered. Tight junction disassembly and paracellular permeability are believed to have an important role in the transport of gluten peptides to the lamina propria. Larazotide acetate is a tight-junction regulator peptide that, in vitro, prevents the opening of intestinal epithelial tight junctions. The aim of this study was to evaluate the efficacy and tolerability of larazotide acetate in protecting against gluten-induced intestinal permeability and gastrointestinal symptom severity in patients with celiac disease.

METHODS

In this dose-ranging, placebo-controlled study, 86 patients with celiac disease controlled through diet were randomly assigned to larazotide acetate (0.25, 1, 4, or 8 mg) or placebo three times per day with or without gluten challenge (2.4 g/day) for 14 days. The primary efficacy outcome was the urinary lactulose/mannitol (LAMA) fractional excretion ratio. Secondary endpoints included gastrointestinal symptom severity, quality-of-life measures, and antibodies to tTG.

RESULTS

LAMA measurements were highly variable in the outpatient setting. The increase in LAMA ratio associated with the gluten challenge was not statistically significantly greater than the increase in the gluten-free control. Among patients receiving the gluten challenge, the difference in the LAMA ratios for the larazotide acetate and placebo groups was not statistically significant. However, larazotide acetate appeared to limit gluten-induced worsening of gastrointestinal symptom severity as measured by the Gastrointestinal Symptom Rating Scale at some lower doses but not at the higher dose. Symptoms worsened significantly in the gluten challenge-placebo arm compared with the placebo-placebo arm, suggesting that 2.4 g of gluten per day is sufficient to induce reproducible gluten toxicity. Larazotide acetate was generally well tolerated. No serious adverse events were observed. The most common adverse events were headache and urinary tract infection.

CONCLUSIONS

LAMA variability in the outpatient setting precluded accurate assessment of the effect of larazotide acetate on intestinal permeability. However, some lower doses of larazotide acetate appeared to prevent the increase in gastrointestinal symptom severity induced by gluten challenge.

The incidence and risk of celiac disease in a healthy US adult population

OBJECTIVES

Celiac disease (CD) is an increasingly common disease that may affect as many as 1% of the North American population. Recent population-based data suggest a substantial increase in the prevalence of CD over the last several decades. Several factors are hypothesized as possible disease triggers including intercurrent illnesses, such as gastroenteritis, surgeries, and trauma. We used the active duty US military, a unique healthy worker population with essentially complete medical diagnostic coding, as an opportunity to describe trends in CD and deployment-related risk factors.

METHODS

Using electronic medical encounter data (1999-2008) on active duty US military (over 13.7 million person-years), a matched, nested case-control study describing the epidemiology and risk determinants of CD (based on ≥2 ICD-9 medical encounters) was conducted. Incidence and duration of CD-related medical care were estimated, and conditional logistic regression was utilized to evaluate CD risk following infectious gastroenteritis (IGE) occurring within 3 years before CD diagnosis while controlling for other risk factors.

RESULTS

A total of 455 incident cases of CD were identified and age, gender, and time matched to 1,820 controls. The incidence of CD increased five-fold from 1.3 per 100,000 in 1999 to 6.5 per 100,000 in 2008, with the highest rates of increase among those over 34 years of age (average annual increase of 0.8 cases per 100,000). A total of 172 IGE episodes, predominately of "viral etiology" (60.5%), were documented. In multivariate models, a significant association between IGE and CD was found (Odds ratio (OR): 2.06, 95% confidence interval (CI) 1.43, 2.97). Risk generally increased with temporal proximity to, and non-viral etiology of, exposure. Other notable risk factors for CD in multivariate models were Caucasian race (OR: 3.1, P<0.001), non-Army service (OR: 1.5, P=0.001), and greater than a high-school education (OR: 1.3, P=0.05).

CONCLUSIONS

Incidence of CD diagnosis in the US military is increasing, particularly among those in the fourth and fifth decades of life and appears higher than other population-based estimates. An association between antecedent IGE and risk of CD was noted, but the potential for exposure misclassification cannot be ruled out and further study is needed to link pathogen-specific exposure to incident CD anti-gluten antibody development or symptom onset.

Review article: coeliac disease, new approaches to therapy

BACKGROUND

Coeliac disease is managed by life-long gluten withdrawal from the diet. However, strict adherence to a gluten-free diet is difficult and is not always effective. Novel therapeutic approaches are needed to supplement or even replace the dietary treatment.

AIM

To review recent advances in new therapeutic options for coeliac disease.

METHODS

A literature search was performed on MEDLINE, EMBASE, Web of Science, Scopus, DDW.org and ClinicalTrials.gov for English articles and abstracts. The search terms used included, but not limited to, 'Celiac disease', 'new', 'novel', 'Advances', 'alternatives' and 'Drug therapy'. The cited articles were selected based on the relevancy to the review objective.

RESULTS

Several new therapeutic approaches for coeliac disease are currently under development by targeting its underlying pathogenesis. Alternative therapies range from reproduction of harmless wheat strains to immunomodulatory approaches. Some of these therapies such as enzymatic cleavage of gluten and permeability inhibitors have shown promise in clinical studies.

CONCLUSIONS

Gluten-free diet is still the only practical treatment for patients with coeliac disease. Novel strategies provide promise of alternative adjunctive approaches to diet restriction alone for patients with this disorder.

Celiac disease, inflammation and oxidative damage: a nutrigenetic approach

Celiac disease (CD), a common heritable chronic inflammatory condition of the small intestine caused by permanent intolerance to gluten/gliadin (prolamin), is characterized by a complex interplay between genetic and environmental factors. Developments in proteomics have provided an important contribution to the understanding of the biochemical and immunological aspects of the disease and the mechanisms involved in toxicity of prolamins. It has been demonstrated that some gliadin peptides resistant to complete proteolytic digestion may directly affect intestinal cell structure and functions by modulating gene expression and oxidative stress. In recent years, the creation of the two research fields Nutrigenomics and Nutrigenetics, has enabled the elucidation of some interactions between diet, nutrients and genes. Various dietary components including long chain ω-3 fatty acids, plant flavonoids, and carotenoids have been demonstrated to modulate oxidative stress, gene expression and production of inflammatory mediators. Therefore their adoption could preserve intestinal barrier integrity, play a protective role against toxicity of gliadin peptides and have a role in nutritional therapy of celiac disease.

Interferon-γ activates transglutaminase 2 via a phosphatidylinositol-3-kinase-dependent pathway: implications for celiac sprue therapy

The mechanism for activation of extracellular transglutaminase 2 (TG2) in the small intestine remains a fundamental mystery in our understanding of celiac sprue pathogenesis. Using the T84 human enterocytic cell line, we show that interferon-γ (IFN-γ), the predominant cytokine secreted by gluten-reactive T cells in the celiac intestine, activates extracellular TG2 in a dose-dependent manner. IFN-γ mediated activation of TG2 requires phosphatidylinositol-3-kinase (PI3K) activity, but is uninfluenced by a number of other kinases reported to be active in T84 cells. Pharmacological inhibition of PI3K in the presence of IFN-γ prevents TG2 activation as well as the previously characterized increase in transepithelial permeability. Our findings therefore establish PI3K as an attractive target for celiac sprue therapy, a possibility that is underscored by the encouraging safety profiles of several PI3K inhibitors undergoing human clinical trials.

Improved xenobiotic metabolism and reduced susceptibility to cancer in gluten-sensitive macaques upon introduction of a gluten-free diet

BACKGROUND

A non-human primate (NHP) model of gluten sensitivity was employed to study the gene perturbations associated with dietary gluten changes in small intestinal tissues from gluten-sensitive rhesus macaques (Macaca mulatta).

METHODOLOGY

Stages of remission and relapse were accomplished in gluten-sensitive animals by administration of gluten-free (GFD) and gluten-containing (GD) diets, as described previously. Pin-head-sized biopsies, obtained non-invasively by pediatric endoscope from duodenum while on GFD or GD, were used for preparation of total RNA and gene profiling, using the commercial Rhesus Macaque Microarray (Agilent Technologies),targeting expression of over 20,000 genes.

PRINCIPAL FINDINGS

When compared with normal healthy control, gluten-sensitive macaques showed differential gene expressions induced by GD. While observed gene perturbations were classified into one of 12 overlapping categories--cancer, metabolism, digestive tract function, immune response, cell growth, signal transduction, autoimmunity, detoxification of xenobiotics, apoptosis, actin-collagen deposition, neuronal and unknown function--this study focused on cancer-related gene networks such as cytochrome P450 family (detoxification function) and actin-collagen-matrix metalloproteinases (MMP) genes.

CONCLUSIONS/SIGNIFICANCE

A loss of detoxification function paralleled with necessity to metabolize carcinogens was revealed in gluten-sensitive animals while on GD. An increase in cancer-promoting factors and a simultaneous decrease in cancer-preventing factors associated with altered expression of actin-collagen-MMP gene network were noted. In addition, gluten-sensitive macaques showed reduced number of differentially expressed genes including the cancer-associated ones upon withdrawal of dietary gluten. Taken together, these findings indicate potentially expanded utility of gluten-sensitive rhesus macaques in cancer research.

Docosahexaenoic acid modulates in vitro the inflammation of celiac disease in intestinal epithelial cells via the inhibition of cPLA2

BACKGROUND & AIMS

The cytosolic phospolypase A(2) (cPLA(2)) - dependent release of arachidonic acid (AA) from the intra-epithelial lymphocytes plays a pivotal role in arming lymphocytes to cytolysis in the immune response of celiac disease. However, little is known about the role of enterocytes in releasing AA. Docosahexaenoic acid (DHA) is a long chain polyunsaturated fatty acid that counteracts many of the proinflammatory effect of AA. The aims of the present work were to evaluate if: 1) intestinal epithelial cells have a role in the celiac inflammation, releasing AA, and 2) if DHA is able to modulate the celiac inflammation, down-regulating the release of AA.

METHODS

A human intestinal epithelial cell line (Caco-2) was exposed to gliadin peptides (PT-gl) (500 μg/ml) and DHA (2 μg/ml), both alone and simultaneously up to 24 h.

RESULTS

The exposure of those cells to PT-gl alone resulted in an increased AA release, cycloxygenase-2 expression, cPLA(2) activity and prostaglandin E(2) and interleukin-8 release in culture medium, whereas the simultaneous exposure of the cells to DHA and PT-gl prevented the above-mentioned increases.

CONCLUSIONS

These results suggest that intestinal epithelial cells sustain the celiac inflammation, releasing AA when stimulated with gliadin and that DHA inhibits the AA release by these cells.

Influence of early feeding practices on celiac disease in infants

AIM

To investigate whether duration of breastfeeding and timing of gluten introduction influence the age at diagnosis and severity of celiac disease.

METHODS

Medical records of 89 infants (59 girls and 30 boys; mean age of 14.2 months, standard deviation 4.80) diagnosed with classic celiac disease at the University Children's Hospital in Belgrade from 2000 to 2008 were retrospectively analyzed to determine the duration of breastfeeding and timing of gluten introduction. The severity of celiac disease was assessed based on weight loss, longitudinal growth retardation, anemia, and secondary lactose intolerance.

RESULTS

Longer breastfeeding significantly reduced the risk that celiac disease would manifest in the first year of life (odds ratio, 0.655; 95% confidence interval, 0.481-0.891; P=0.007), and duration of breastfeeding was the most significant predictor of developing celiac disease (B=0.49; 95% confidence interval, 0.131-0.768; P=0.007). There were no significant differences in age at diagnosis between infants who had started consuming gluten before the fourth month and those who had started between the fourth and sixth month. Neither breastfeeding nor timing of gluten introduction affected the severity of the disease.

CONCLUSION

Longer breastfeeding and continuation of breastfeeding after gluten introduction delay the onset of classic celiac disease. On the other hand, neither breastfeeding nor the timing of gluten introduction affects the severity of celiac disease.