The top 100 most cited articles in the past 30 years of wheat allergy: a bibliometric analysis

Background

Wheat allergy (WA), characterized by immunological responses to wheat proteins, is a gluten-related disorder that has become increasingly recognized in recent years. Bibliometrics involves the quantitative assessment of publications within a specific academic domain.

Objectives

We aimed to execute an extensive bibliometric study, focusing on the past 30 years of literature related to wheat allergy.

Methods

We searched the Web of Science database on 5th Dec 2023. We used the keywords "wheat allergy or wheat anaphylaxis or wheat hypersensitivity," "gliadin allergy or gliadin anaphylaxis or gliadin hypersensitivity," "wheat-dependent exercise-induced anaphylaxis," and "baker's asthma" for our search. All items published between 1993 and 2023 were included. The top 100 most cited articles were identified and analyzed.

Results

Our study conducted an in-depth bibliometric analysis of the 100 most-cited articles in the field of wheat allergy, published between 2002 and 2019. These articles originated from 20 different countries, predominantly Japan and Germany. The majority of these articles were centered on the pathogenesis and treatment of wheat allergy (WA). The Journal of Allergy and Clinical Immunology (JACI) was the most prolific contributor to this list, publishing 14 articles. The article with the highest citation count was published by Biomed Central (BMC) and garnered 748 citations. The peak citation year was 2015, with a total of 774 citations, while the years 1998, 2001, and 2005 saw the highest publication frequency, each with 7 articles.

Conclusion

Our study aims to provide physicians and researchers with a historical perspective for the scientific progress of wheat allergy, and help clinicians effectively obtain useful articles that have a significant impact on the field of wheat allergy.

A possible unexpected link: Could wheat elimination trigger food protein-induced enterocolitis syndrome in a celiac disease patient?

Cases of association between celiac disease and wheat allergy have been described in the literature. However, to date, no reported cases have linked celiac disease with wheat food protein-induced enterocolitis syndrome (FPIES). We report a case of this association. A child diagnosed with celiac disease at the age of 2 years, following a gluten-free diet, experienced uncontrollable vomiting, and subsequent hypotension within 2 h of accidental ingestion of wheat flour. As a result, the child required hospitalization for fluid therapy. A similar episode occurred when the child turned 5 y, again resulting from accidental gluten ingestion. This time, the symptoms included vomiting, hypotension, and a loss of consciousness, leading to hospitalization for rehydration treatment. After this second episode, on suspicion of FPIES, the patient was referred to the pediatric allergists, who confirmed the diagnosis. To our knowledge, this is the first case of an association between celiac disease and FPIES. It has been hypothesized that exclusion diets in food-allergic children may lead to an increase in specific immunoglobulin E levels for those foods and, consequently, the risk of anaphylaxis. However, FPIES is not an immunoglobulin E-mediated condition. Hence, further investigations are warranted to elucidate the underlying mechanisms linking these 2 disorders.

Positive rate of wheat allergens in the Chinese allergic population: a systematic review and meta-analysis

In recent years, the prevalence of allergic diseases has increased significantly, causing great concern, and wheat, as one of the top 8 food allergens, is a common allergy trigger. Nevertheless, reliable estimates of the positivity rate of wheat allergens in the allergic population in China are still lacking. The systematic review and meta-analysis aims to evaluate the positive detection rate of wheat allergens in the Chinese allergic population and further provide a reference for the prevention of allergy. CNKI, CQVIP, WAN-FANG DATA, Sino Med, PubMed, Web of Science, Cochrane Library, and Embase databases were retrieved. Related research and case reports about the positive rate of wheat allergen in the Chinese allergic population published from inception to June 30, 2022, were searched, and meta-analysis was performed using Stata software. The pooled positive rate of wheat allergens and 95% confidence interval were calculated by random effect models, and the publication bias was evaluated using Egger's test. A total of 13 articles were included for the final meta-analysis, in which wheat allergen detection methods involved only serum sIgE testing and SPT assessment. The results showed that the wheat allergen positivity detection rate in Chinese allergic patients was 7.30% (95% CI 5.68-8.92%). Subgroup analysis showed that the positivity rate of wheat allergens was influenced by region, but hardly by age and assessment method. The positive rates of wheat allergy in the population with allergic diseases were 2.74% (95% CI 0.90-4.58%) and 11.47% (95% CI 7.08-15.87%) in southern and northern China, respectively. In particular, the positive rates of wheat allergens were greater than 10% in Shaanxi, Henan and Nei Mongol, all of which belong to the northern region. These results suggest that wheat allergens are an important cause of sensitization in allergic populations from northern China, and therefore attention should be paid to early prevention in high-risk populations.

Wheat Sensitivity and Functional Dyspepsia: A Pilot, Double-Blind, Randomized, Placebo-Controlled Dietary Crossover Trial with Novel Challenge Protocol

Introduction: Functional dyspepsia (FD), characterised by symptoms of epigastric pain or early satiety and post prandial distress, has been associated with duodenal eosinophilia, raising the possibility that it is driven by an environmental allergen. Non-coeliac gluten or wheat sensitivity (NCG/WS) has also been associated with both dyspeptic symptoms and duodenal eosinophilia, suggesting an overlap between these two conditions. The aim of this study was to evaluate the role of wheat (specifically gluten and fructans) in symptom reduction in participants with FD in a pilot randomized double-blind, placebo controlled, dietary crossover trial. Methods: Patients with Rome III criteria FD were recruited from a single tertiary centre in Newcastle, Australia. All were individually counselled on a diet low in both gluten and fermentable oligo-, di-, mono-saccharides, and polyols (FODMAPs) by a clinical dietitian, which was followed for four weeks (elimination diet phase). Those who had a ≥30% response to the run-in diet, as measured by the Nepean Dyspepsia Index, were then re-challenged with ‘muesli’ bars containing either gluten, fructan, or placebo in randomised order. Those with symptoms which significantly reduced during the elimination diet, but reliably reappeared (a mean change in overall dyspeptic symptoms of ≥30%) with gluten or fructan re-challenge were deemed to have wheat induced FD. Results: Eleven participants were enrolled in the study (75% female, mean age 43 years). Of the initial cohort, nine participants completed the elimination diet phase of whom four qualified for the rechallenge phase. The gluten-free, low FODMAP diet led to an overall (albeit non-significant) improvement in symptoms of functional dyspepsia in the diet elimination phase (mean NDI symptom score 71.2 vs. 47.1, p = 0.087). A specific food trigger could not be reliably demonstrated. Conclusions: Although a gluten-free, low-FODMAP diet led to a modest overall reduction in symptoms in this cohort of FD patients, a specific trigger could not be identified. The modified Salerno criteria for NCG/WS identification trialled in this dietary rechallenge protocol was fit-for-purpose. However, larger trials are required to determine whether particular components of wheat induce symptoms in functional dyspepsia.

Wheat Consumption Leads to Immune Activation and Symptom Worsening in Patients with Familial Mediterranean Fever: A Pilot Randomized Trial

We have identified a clinical association between self-reported non-celiac wheat sensitivity (NCWS) and Familial Mediterranean Fever (FMF). Objectives: A) To determine whether a 2-week double-blind placebo-controlled (DBPC) cross-over wheat vs. rice challenge exacerbates the clinical manifestations of FMF; B) to evaluate innate immune responses in NCWS/FMF patients challenged with wheat vs. rice. The study was conducted at the Department of Internal Medicine of the University Hospital of Palermo and the Hospital of Sciacca, Italy. Six female volunteers with FMF/NCWS (mean age 36 ± 6 years) were enrolled, 12 age-matched non-FMF, NCWS females, and 8 sex- and age-matched healthy subjects served as controls. We evaluated: 1. clinical symptoms by the FMF-specific AIDAI (Auto-Inflammatory Diseases Activity Index) score; 2. serum soluble CD14 (sCD14), C-reactive protein (CRP), and serum amyloid A (SSA); 3. circulating CD14+ monocytes expressing interleukin (IL)-1β and tumor necrosis factor (TNF)-α. The AIDAI score significantly increased in FMF patients during DBPC with wheat, but not with rice (19 ± 6.3 vs. 7 ± 1.6; p = 0.028). sCD14 values did not differ in FMF patients before and after the challenge, but were higher in FMF patients than in healthy controls (median values 11357 vs. 8710 pg/ml; p = 0.002). The percentage of circulating CD14+/IL-1β+ and of CD14+/TNF-α+ monocytes increased significantly after DBPC with wheat vs. baseline or rice challenge. Self-reported NCWS can hide an FMF diagnosis. Wheat ingestion exacerbated clinical and immunological features of FMF. Future studies performed on consecutive FMF patients recruited in centers for auto-inflammatory diseases will determine the real frequency and relevance of this association.

Irritable Bowel Syndrome and Gluten-Related Disorders

Background: Irritable bowel syndrome (IBS) is frequently associated with celiac disease (CD) and nonceliac gluten/wheat sensitivity (NCGS/NCWS), but epidemiological and pathophysiological aspects are still unclear. Furthermore, a gluten-free diet (GFD) can positively influence IBS symptoms. Methods: A comprehensive online search for IBS related to CD, NCGS and GFD was made using the Pubmed, Medline and Cochrane databases. Results: Although a systematic screening for CD in IBS is not recommended, CD prevalence can be increased in diarrhea-predominant IBS patients. On the other hand, IBS symptoms can be persistent in treated CD patients, and their prevalence tends to decrease on a GFD. IBS symptoms may overlap and be similar to those associated to nonceliac gluten and/or wheat sensitivity. Increased gut permeability could explain the gluten/wheat effects in IBS patients. Finally, a GFD could improve symptoms in a subgroup of IBS patients. Conclusions: The possible interplay between IBS and gluten-related disorders represents a scientifically and clinically challenging issue. Further studies are needed to confirm these data and better clarify the involved pathophysiological mechanisms.

Advances in Molecular Mechanisms of Wheat Allergenicity in Animal Models: A Comprehensive Review

The prevalence of wheat allergy has reached significant levels in many countries. Therefore, wheat is a major global food safety and public health issue. Animal models serve as critical tools to advance the understanding of the mechanisms of wheat allergenicity to develop preventive and control methods. A comprehensive review on the molecular mechanisms of wheat allergenicity using animal models is unavailable at present. There were two major objectives of this study: To identify the lessons that animal models have taught us regarding the molecular mechanisms of wheat allergenicity and to identify the strengths, challenges, and future prospects of animal models in basic and applied wheat allergy research. Using the PubMed and Google Scholar databases, we retrieved and critically analyzed the relevant articles and excluded celiac disease and non-celiac gluten sensitivity. Our analysis shows that animal models can provide insight into the IgE epitope structure of wheat allergens, effects of detergents and other chemicals on wheat allergenicity, and the role of genetics, microbiome, and food processing in wheat allergy. Although animal models have inherent limitations, they are critical to advance knowledge on the molecular mechanisms of wheat allergenicity. They can also serve as highly useful pre-clinical testing tools to develop safer genetically modified wheat, hypoallergenic wheat products, novel pharmaceuticals, and vaccines.

Involvement of gliadin, a component of wheat gluten, in increased intestinal permeability leading to non-steroidal anti-inflammatory drug-induced small-intestinal damage

Gliadin, a component of wheat gluten known to be an important factor in the etiology of celiac disease, is related to several other diseases through its enhancing effect on intestinal paracellular permeability. We investigated the significance of gliadin in non-steroidal anti-inflammatory drug (NSAID)-induced small-intestinal damage in mice. 7-week-old C57BL/6 male mice were divided into the following groups: standard diet group, in which mice were fed with wheat-containing standard rodent diet (CE-2); gluten-free diet group, in which mice were fed with gluten-free diet (AIN-76A); and gliadin-administered group, in which mice fed with gluten-free diet were administered with gliadin (~250 mg/kg BW). Each group was subdivided into negative, healthy control group and NSAID-treated group. To some mice fed with gluten-free diet and administered with gliadin, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor was administered for clarification of the significance of EGFR in NSAID-induced small intestinal damage and intestinal permeability. In mice fed with a gluten-free diet, indomethacin or diclofenac induced very mild mucosal damage in the small intestine compared with that in mice fed with a wheat-containing standard diet. Gliadin exacerbated the NSAID-induced small-intestinal damage in mice fed with a gluten-free diet. With the administration of indomethacin, MPO activity, a marker of neutrophil infiltration into the mucosa and mRNA expression level of tumor necrosis factor α and interleukin-1β in the small intestine were higher in the gliadin-administered mice. Gliadin increased the intestinal paracellular permeability without indomethacin administration (4.3-fold) and further increased the permeability after indomethacin administration (2.1-fold). Gliadin induced phosphorylation of epidermal growth factor receptor (EGFR) in small-intestinal tissues, and erlotinib (an EGFR tyrosine kinase inhibitor) attenuated the indomethacin-induced intestinal damage and permeability exacerbated by gliadin, accompanied by inhibition of EGFR phosphorylation. These results suggest that gliadin plays an important role in the induction and exacerbation of NSAID-induced small-intestinal damage, and that increase in intestinal permeability via the EGFR signalling pathway is involved in its mechanism.

Energy Expenditure and Hormone Responses in Humans After Overeating High-Fructose Corn Syrup Versus Whole-Wheat Foods

OBJECTIVE

This study sought to understand how the dietary source of carbohydrates, either high-fructose corn syrup (HFCS) or complex carbohydrates, affects energy expenditure (EE) measures, appetitive sensations, and hormones during 24 hours of overfeeding.

METHODS

Seventeen healthy participants with normal glucose regulation had 24-hour EE measures and fasting blood and 24-hour urine collection during four different 1-day diets, including an energy-balanced diet, fasting, and two 75% carbohydrate diets (5% fat) given at 200% of energy requirements with either HFCS or whole-wheat foods as the carbohydrate source. In eight volunteers, hunger was assessed with visual analog scales the morning after the diets.

RESULTS

Compared with energy balance, 24-hour EE increased 12.8% ± 6.9% with carbohydrate overfeeding (P < 0.0001). No differences in 24-hour EE or macronutrient utilization were observed between the two high-carbohydrate diets; however, sleeping metabolic rate was higher after the HFCS diet (Δ = 35 ± 48 kcal [146 ± 200 kJ]; P = 0.01). Insulin, ghrelin, and triglycerides increased the morning after both overfeeding diets. Urinary cortisol concentrations (82.8 ± 35.9 vs. 107.6 ± 46.9 nmol/24 h; P = 0.01) and morning-after hunger scores (Δ = 2.4 ± 2.0 cm; P = 0.01) were higher with HFCS overfeeding.

CONCLUSIONS

The dietary carbohydrate source while overeating did not affect 24-hour EE, but HFCS overconsumption may predispose individuals to further overeating due to increased glucocorticoid release and increased hunger the following morning.

Effectiveness of Germination on Protein Hydrolysis as a Way To Reduce Adverse Reactions to Wheat

In this work, the aim is to study the effectiveness of germination on wheat protein degradation, with a specific focus on proteins involved in adverse reactions to wheat. The effects of 8 days of germination at 25 °C on the chemical composition and the protein profile were determined. Germination did not have a significant effect on starch, protein, lipid, and ash contents. General protein profile, as indicated by SDS-PAGE analysis, revealed that germination induced a relevant degradation in protein fraction. After in vitro gastrointestinal digestion, gluten peptides involved in celiac disease (CD) were identified and quantified using UPLC/ESI-MS technique. Also, CM3 protein, involved in baker's asthma and intestinal inflammation, was quantified by measuring a marker peptide. Statistical analysis underlined that germination and genotype had significant impact on the amount of both components. Regarding gluten peptides related to CD, germination enabled an average reduction of 47% in peptides eliciting adaptive immune response and 46% in peptides eliciting innate immune response. CM3 protein showed also a high average reduction (56%). Thus, this study suggests that germination might be a good bioalternative to provide a low "impact" raw ingredient for special wheat-based foodstuffs.

A New Proposal for the Pathogenic Mechanism of Non-Coeliac/Non-Allergic Gluten/Wheat Sensitivity: Piecing Together the Puzzle of Recent Scientific Evidence

Non-coeliac/non-allergic gluten/wheat sensitivity (NCG/WS) is a gluten-related disorder, the pathogenesis of which remains unclear. Recently, the involvement of an increased intestinal permeability has been recognized in the onset of this clinical condition. However, mechanisms through which it takes place are still unclear. In this review, we attempt to uncover these mechanisms by providing, for the first time, an integrated vision of recent scientific literature, resulting in a new hypothesis about the pathogenic mechanisms involved in NCG/WS. According to this, the root cause of NCG/WS is a particular dysbiotic profile characterized by decreased butyrate-producing-Firmicutes and/or Bifidobacteria, leading to low levels of intestinal butyrate. Beyond a critical threshold of the latter, a chain reaction of events and vicious circles occurs, involving other protagonists such as microbial lipopolysaccharide (LPS), intestinal alkaline phosphatase (IAP) and wheat α-amylase trypsin inhibitors (ATIs). NCG/WS is likely to be a multi-factor-onset disorder, probably transient and preventable, related to quality and balance of the diet, and not to the presence of gluten in itself. If future studies confirm our proposal, this would have important implications both for the definition of the disease, as well as for the prevention and therapeutic-nutritional management of individuals with NCG/WS.

Usefulness of antigen-specific IgE probability curves derived from the 3gAllergy assay in diagnosing egg, cow's milk, and wheat allergies

BACKGROUND

Specific IgE (sIgE) antibody detection using the Siemens IMMULITE^® 3gAllergy™ (3gAllergy) assay have not been sufficiently examined for the diagnosis of food allergy. The aim of this study was to evaluate the utility of measuring sIgE levels using the 3gAllergy assay to diagnose allergic reactions to egg, milk, and wheat.

METHODS

This retrospective study was conducted on patients with diagnosed or suspected allergies to egg, milk and wheat. Patients were divided into two groups according to their clinical reactivity to these allergens based on oral food challenge outcomes and/or convincing histories of immediate reaction to causative food(s). The sIgE levels were measured using 3gAllergy and ImmunoCAP. Predicted probability curves were estimated using logistic regression analysis.

RESULTS

We analyzed 1561 patients, ages 0-19 y (egg = 436, milk = 499, wheat = 626). The sIgE levels determined using 3gAllergy correlated with those of ImmunoCAP, classifying 355 patients as symptomatic: egg = 149, milk = 123, wheat = 83. 3gAllergy sIgE levels were significantly higher in symptomatic than in asymptomatic patients (P < 0.0001). Predictive probability for positive food allergy was significantly increased and correlated with increased sIgE levels. The cut-offs for allergic reaction with 95% predictive probability as determined by the 3gAllergy probability curves were different from those of ImmunoCAP.

CONCLUSIONS

Measurements of sIgE against egg, milk, and wheat as determined by 3gAllergy may be used as a tool to facilitate the diagnosis of food allergy in subjects with suspected food allergies. However, these probability curves should not be applied interchangeably between different assays.

Contact Dermatitis Due to Nickel Allergy in Patients Suffering from Non-Celiac Wheat Sensitivity

Background: Non-celiac wheat sensitivity (NCWS) is a new clinical entity in the world of gluten-related diseases. Nickel, the most frequent cause of contact allergy, can be found in wheat and results in systemic nickel allergy syndrome and mimics irritable bowel syndrome (IBS). Objective: To evaluate the frequency of contact dermatitis due to nickel allergy in NCWS patients diagnosed by a double-blind placebo-controlled (DBPC) challenge, and to identify the characteristics of NCWS patients with nickel allergy. Methods: We performed a prospective study of 60 patients (54 females, 6 males; mean age 34.1 ± 8.1 years) diagnosed with NCWS from December 2014 to November 2016; 80 age- and sex-matched subjects with functional gastrointestinal symptoms served as controls. Patients reporting contact dermatitis related to nickel-containing objects underwent nickel patch test (Clinicaltrials.gov registration number: NCT02750735). Results: Six out of sixty patients (10%) with NCWS suffered from contact dermatitis and nickel allergy and this frequency was statistically higher (p = 0.04) than observed in the control group (5%). The main clinical characteristic of NCWS patients with nickel allergy was a higher frequency of cutaneous symptoms after wheat ingestion compared to NCWS patients who did not suffer from nickel allergy (p < 0.0001). Conclusions: Contact dermatitis and nickel allergy are more frequent in NCWS patients than in subjects with functional gastrointestinal disorders; furthermore, these patients had a very high frequency of cutaneous manifestations after wheat ingestion. Nickel allergy should be evaluated in NCWS patients who have cutaneous manifestations after wheat ingestion.

Managing symptoms and health through self-prescribed restrictive diets: What can general practitioners learn from the phenomenon of wheat avoidance?

BACKGROUND

Seven per cent of Australian adults report avoiding wheat products for the relief of symptoms. The objective of this study was to explore the experiences, symptoms, influences and beliefs that may explain the tendency for this behaviour to occur pre-dominantly in the absence of a reported medical diagnosis or expert dietary supervision.

METHODS

Data were collected through preliminary questionnaires and semi-structured interviews with 35 self-identified symptomatic individuals who avoid consumption of wheat-based products without a diagnosis of coeliac disease or wheat allergy.

RESULTS

Like other contested health phenomena, symptomatic wheat avoidance is characterised by broad symptomatology, perceived benefits, absence of clear biological markers, dissatisfaction with conventional medicine following previous negative test results, and the fact that presumed treatment - elimination of a dietary factor - requires no medical intervention.

DISCUSSION

Self-prescribed food avoidance represents a diagnostic and therapeutic challenge for practitioners, central to which is a tension between patient expectations and biomedical standards of evidence in the diagnostic relationship.

Long-term response to gluten-free diet as evidence for non-celiac wheat sensitivity in one third of patients with diarrhea-dominant and mixed-type irritable bowel syndrome

PURPOSE

Irritable bowel syndrome (IBS) is common but therapies are unsatisfactory. Food is often suspected as cause by patients, but diagnostic procedures, apart from allergy testing, are limited. Based on the hypothesis of non-celiac wheat sensitivity (WS) in a subgroup of IBS patients, we tested the long-term response to a gluten-free diet (GFD) and investigated HLA-DQ2 or -DQ8 expression as a diagnostic marker for WS in diarrhea-dominant (IBS-D) and mixed-type IBS (IBS-M).

METHODS

The response to a GFD served as reference test for WS and HLA-DQ2/8 expression was determined as index test. Patients were classified as responders if they reported complete or considerable relief of IBS symptoms on at least 75 % of weeks over a 4-month period of gluten-free diet. Established questionnaires (IBS-Quality of Life (IBS-QoL), IBS Symptom Severity Scale (IBS-SSS), European Quality of Life-5 Dimensions (EQ-5D)) were used for secondary outcome measures.

RESULTS

Thirty-five patients finished the study. Of these, 12 (34 %) were responders and classified as having WS (95 % CI 21-51 %). HLA-DQ2/8 expression had a specificity of 52 % (95 % CI 33-71 %) and sensitivity of 25 % (95 % CI 8-54 %) for WS. Responders showed improvement in quality of life and symptom scores. At 1-year follow-up, all responders and 55 % of non-responders were still on GFD and reported symptom relief.

CONCLUSION

Using strict criteria as recommended for IBS studies, about one third of patients with IBS-D or IBS-M are wheat sensitive, with a similar proportion in both IBS types. Expression of HLA-DQ2/8 is not useful as diagnostic marker for WS. Long-term adherence to a GFD is high and can sustain symptomatic improvement.

Coeliac disease

Essential facts [Figure: see text] Coeliac disease is a lifelong autoimmune condition where the body reacts to eating gluten, a protein found in wheat, rye and barley. This leads to chronic inflammation of the small intestine and can result in malabsorption of nutrients.

Nonceliac Gluten Sensitivity

Nonceliac gluten sensitivity (NCGS) refers to a clinical phenotype in which patients experience intestinal and extraintestinal symptoms related to ingesting a gluten-containing diet after a diagnosis of celiac disease (CD) or wheat allergy has been excluded. CD, an autoimmune disease characterized by villous atrophy triggered by the ingestion of gluten, has increased in prevalence in recent decades, although the majority of patients remain undiagnosed. There is now an increasing public awareness of NCGS and growing interest in the health effects of gluten among health professionals and the lay public. Several randomized controlled trials have explored NCGS but have left many questions unanswered surrounding the pathophysiology, biomarkers, and established diagnostic approach to patients with this condition. Future studies are necessary to establish biomarkers and to elucidate the pathophysiology of this condition because at present, NCGS likely comprises a heterogeneous patient population. In this review, we outline the clinical trials of NCGS as well as the approach to patients with possible NCGS as recommended by an international expert panel. Because maintaining a gluten-free diet has important health, social, and economic consequences, it is necessary for medical professionals to provide practical and evidence-based advice to patients with this condition.

Characterization of a hypoallergenic wheat line lacking ω-5 gliadin

BACKGROUND

There is no curative treatment for wheat-dependent exercise-induced anaphylaxis (WDEIA). ω-5 Gliadin is one of the dominant allergens affecting WDEIA patients. The use of ω-5 gliadin-free wheat flour in the regular diet is considered one of the prophylactic approaches against the elicitation of allergic symptoms and sensitization to ω-5 gliadin. We sought to find hypoallergenic bread wheat (or common wheat) that lacked the genes encoding ω-5 gliadin and to evaluate its in vitro allergenicity. We also aimed to evaluate the sensitization ability of one of the selected hypoallergenic wheat lines by using a possible animal model of wheat allergy.

METHODS

We screened the deletion lines of bread wheat by western blotting to ascertain common wheat lines lacking the ω-5 gliadin locus. The deletion lines we used have partial deficiency of chromosome 1B (Endo and Gill, 1996). To assess sensitization ability of gluten from the selected deletion line, guinea pigs were fed with either the gluten from the selected deletion line or commercially available gluten, and allergic score was evaluated after challenging the same gluten preparations.

RESULTS

We found that a deletion line 1BS-18 had the least deficiency of chromosome 1B among the deletion stocks lacking the ω-5 gliadin locus. The challenge test using the guinea pigs revealed that the symptoms induced by application of the 1BS-18 gluten were much less than that of commercially available gluten.

CONCLUSIONS

The deletion line 1BS-18, which lacked the ω-5 gliadin locus, is likely to have a low sensitization capacity in the guinea pig. The use of the wheat products of the 1BS-18 line in daily life may provide a feasible solution for the onset of wheat allergy.

Structural, Culinary, Nutritional and Anti-Nutritional Properties of High Protein, Gluten Free, 100% Legume Pasta

Wheat pasta has a compact structure built by a gluten network entrapping starch granules resulting in a low glycemic index, but is nevertheless unsuitable for gluten-intolerant people. High protein gluten-free legume flours, rich in fibers, resistant starch and minerals are thus a good alternative for gluten-free pasta production. In this study, gluten-free pasta was produced exclusively from faba, lentil or black-gram flours. The relationship between their structure, their cooking and Rheological properties and their in-vitro starch digestion was analyzed and compared to cereal gluten-free commercial pasta. Trypsin inhibitory activity, phytic acid and α-galactosides were determined in flours and in cooked pasta. All legume pasta were rich in protein, resistant starch and fibers. They had a thick but weak protein network, which is built during the pasta cooking step. This particular structure altered pasta springiness and increased cooking losses. Black-gram pasta, which is especially rich in soluble fibers, differed from faba and lentil pasta, with high springiness (0.85 vs. 0.75) and less loss during cooking. In comparison to a commercial cereal gluten-free pasta, all the legume pasta lost less material during cooking but was less cohesive and springy. Interestingly, due to their particular composition and structure, lentil and faba pasta released their starch more slowly than the commercial gluten-free pasta during the in-vitro digestion process. Anti-nutritional factors in legumes, such as trypsin inhibitory activity and α-galactosides were reduced by up to 82% and 73%, respectively, by pasta processing and cooking. However, these processing steps had a minor effect on phytic acid. This study demonstrates the advantages of using legumes for the production of gluten-free pasta with a low glycemic index and high nutritional quality.

Selection of lactic acid bacteria strains for the hydrolysis of allergenic proteins of wheat flour

BACKGROUND

Wheat flour is one of the most common causative agents of food allergy. The study presents the selection and characterization of lactic acid bacteria (LAB) strains capable of hydrolyzing/modifying allergenic proteins of wheat flour. Hydrolysis of wheat proteins was determined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with sera from patients with food allergy to gluten.

RESULTS

The analysis of electrophoretic profiles of protein extracted from sourdough shows the capability of selected LAB strains for proteolytic degradation of wheat proteins that belong to two factions: albumin/globulin (hydrolysis of 13 polypeptides with a molecular weight between 103 and 22 kDa); and gliadin (seven polypeptides with a molecular weight between 39 and 24 kDa). All analyzed strains were capable of hydrolyzing some IgE-binding epitopes of wheat allergens. The lack of such changes in control samples indicates that they were induced rather by the proteolytic activity of bacterial strains than endogenous enzymes of wheat flour. The gluten proteins were susceptible to hydrolysis by sequential digestion with pepsin and trypsin.

CONCLUSION

The selected strains exhibit proteolytic activity, which leads to a reduction in allergenicity of wheat sourdoughs. These strains may be applied as specific starter cultures to prepare bakery products of special nutritional use. © 2015 Society of Chemical Industry.

Other Dietary Confounders: FODMAPS et al

BACKGROUND

While it is well documented and widely appreciated that ingestion of wheat (and less so rye and barley) is associated with gastrointestinal symptoms such as bloating or abdominal pain, the component of wheat to which such an effect is attributed is less well established.

KEY MESSAGES

Wheat is a complex of proteins (80% gluten, 20% metabolic proteins), carbohydrates (starch, non-starch polysaccharides, fructans), lipids and other components. The majority of attention has focused on gluten as the culprit in triggering symptoms, but re-challenge studies have nearly all used wheat flour-related products (such as bread) as the stimulus. When carbohydrate-deplete gluten was used as the challenge agent, gluten-specific feelings of depression and not gut symptoms were observed in those who fulfilled strict criteria of 'non-coeliac gluten sensitivity', thereby underlining the complexity of cereals and of undertaking research in this area. Candidate components other than gluten include poorly absorbed oligosaccharides (mainly fructans), non-gluten wheat proteins such as amylase-trypsin inhibitors or wheat germ agglutinin, and exorphins released during the digestion of gluten. Specific biological and/or clinical effects associated with gluten-free diets or wheat ingestion need to be carefully dissected before attribution to gluten can be claimed.

CONCLUSIONS

Currently, coeliac disease is the only common condition that has been unequivocally linked to gluten. Inaccurate attribution will be associated with suboptimal therapeutic advice and at least partly underlies the current gluten-free epidemic gripping the Western world.

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.

A new reliable method for detecting specific IgE antibodies in the patients with immediate type wheat allergy due to hydrolyzed wheat protein: correlation of its titer and clinical severity

BACKGROUND

Immediate-type wheat allergy caused by a specific hydrolyzed wheat protein (HWP-IWA), Glupearl 19S (GP19S), typically develops food-dependent exercise-induced anaphylaxis (FDEIA), but is different from conventional FDEIA, or simple wheat allergy in many aspects. The skin prick test (SPT) is considered to be the most effective method for diagnosis of HWP-IWA. As SPT is a relatively qualitative method, we developed quantitative and high-throughput test method for HWP-IWA.

METHODS

An enzyme-linked immunosorbent assay (ELISA)-based GP19S-specific IgE assay was tested using sera from 14 HWP-IWA and five conventional wheat-dependent exercise-induced anaphylaxis (CO-WDEIA) patients, as well as five healthy subjects. Then a validation study at five different institutions was carried out using sera from 10 HWP-IWA and five CO-WDEIA patients, as well as five healthy subjects different from the previous studies.

RESULTS

The mean unit values converted from measured absorbance of ELISA were 68.3, 1.3 and 1.1 respectively. Furthermore, the validation study revealed reproducible results across all five institutions, with the standard deviation (SD) being 0.3-0.4 for the healthy group, 0.2-0.6 for the CO-WDEIA group, and 3.8-9.6 for HWP-IWA group except for one case. One case of HWP-IWA was excluded from analysis due to the high SD of 53.3 units, indicating that samples with a unit value > 100.0 will affect inter-laboratory reproducibility.

CONCLUSIONS

Our findings suggest that the ELISA-based GP19S-specific IgE assay can be used to test HWP-IWA using venous blood samples, except for those with a unit value > 100.0.

Nutritional properties of einkorn wheat (Triticum monococcum L.)

The hulled wheat einkorn (Triticum monococcum L. ssp. monococcum), a staple food of early farmers for many thousand years, today is cropped only in small areas of the Mediterranean region and continental Europe. Increasing attention to the nutritional quality of foods has fostered renewed interest in this low-impact crop. The reappraisal of einkorn quality evidenced that this ancient wheat has some dietary advantages over polyploid wheats. Einkorn wholemeal is poor in dietary fibre but rich in proteins, lipids (mostly unsaturated fatty acids), fructans and trace elements (including zinc and iron). The good concentration of several antioxidant compounds (carotenoids, tocols, conjugated polyphenols, alkylresorcinols and phytosterols) and low β-amylase and lipoxygenase activities (which limit antioxidant degradation during food processing) contribute to the excellent nutritional properties of its flour, superior to those of other wheats. Conversely, einkorn has relatively low bound polyphenol content and high polyphenol oxidase activity. In spite of eliciting weaker toxic reactions than other Triticum species, einkorn is not suitable for coeliacs. Current trends towards the consumption of functional foods suggest that this cereal may still play a significant role in human consumption, especially in the development of new or special foods with superior nutritional quality.

Maize prolamins could induce a gluten-like cellular immune response in some celiac disease patients

Celiac disease (CD) is an autoimmune-mediated enteropathy triggered by dietary gluten in genetically prone individuals. The current treatment for CD is a strict lifelong gluten-free diet. However, in some CD patients following a strict gluten-free diet, the symptoms do not remit. These cases may be refractory CD or due to gluten contamination; however, the lack of response could be related to other dietary ingredients, such as maize, which is one of the most common alternatives to wheat used in the gluten-free diet. In some CD patients, as a rare event, peptides from maize prolamins could induce a celiac-like immune response by similar or alternative pathogenic mechanisms to those used by wheat gluten peptides. This is supported by several shared features between wheat and maize prolamins and by some experimental results. Given that gluten peptides induce an immune response of the intestinal mucosa both in vivo and in vitro, peptides from maize prolamins could also be tested to determine whether they also induce a cellular immune response. Hypothetically, maize prolamins could be harmful for a very limited subgroup of CD patients, especially those that are non-responsive, and if it is confirmed, they should follow, in addition to a gluten-free, a maize-free diet.

Fermentable fibers do not affect satiety or food intake by women who do not practice restrained eating

BACKGROUND

Fiber is thought to enhance satiety, although not all fibers are equally effective. Colonic fermentation may influence satiety and food intake.

OBJECTIVE

To test the satiating properties of four isolated fibers added to chocolate crisp bars.

DESIGN

Within-subject preload design with repeated measures. Each participant completed five conditions, presented in random order.

SUBJECTS

Participants were 22 adult women who do not practice restrained eating (body mass index 18 to 29).

INTERVENTION

The experimental conditions were four fiber treatments: 10 g oligofructose, inulin, soluble corn fiber, or resistant wheat starch in chocolate crisp bars. A no-added-fiber bar was evaluated as the control. The night before each treatment, participants consumed a dinner bar containing 10 g of the same fiber given the next morning.

MAIN OUTCOME MEASURES

Repeated ratings of feelings related to hunger and fullness at the lunch meal were the main measures. Secondary outcomes included breath hydrogen and methane, gastrointestinal symptoms, energy consumed at an ad libitum lunch, and energy from 24-hour dietary recall.

STATISTICAL ANALYSES PERFORMED

Mixed-effect linear models with random intercept for participants to model within-subject correlation.

RESULTS

All treatments were well tolerated. No differences were found in subjective satiety during the morning or food intake at lunch or over 24 hours. The oligofructose bar produced the greatest increase in breath hydrogen, and the most bloating and flatulence symptoms.

CONCLUSIONS

Functional fibers incorporated into chocolate bars at high fiber doses produce greater gastrointestinal symptoms than control, but do not alter satiety, hunger, or food intake compared with control in the short term.

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.

[The sensitivity and clinical course of patients with wheat-dependent exercise-induced anaphylaxis sensitized to hydrolyzed wheat protein in facial soap]

BACKGROUND

Recently an increasing number of patients with wheat-dependent exercise-induced anaphylaxis (WDEIA), developed during or after using hydrolyzed wheat protein (HWP)-containing soap (HWP-WDEIA), were reported in Japan.

METHODS

To clarify the relation between WDEIA and HWP-containing soap and their prognosis, we investigated the patients who visited Hiroshima University Hospital and were diagnosed as WDEIA from January 2010 to June 2011. We took detailed clinical histories, performed skin prick tests, serum immunoassays for antigen-specific IgE and basophil histamine release test, and followed up their clinical courses after the diagnosis.

RESULTS

Among 36 patients with WDEIA, 30 patients had used only one type of HWP-soap. The patients with HWP-WDEIA were mainly women and had developed facial symptoms and angioedema. They suffered from blood pressure reductions less frequently than patients with conventional WDEIA. The levels of glutens-specific IgE were higher than those of ω-5 gliadin in patients with HWP-WDEIA (p<0.05, One-way ANOVA). All patients with HWP-WDEIA were positive against HWP in histamine release test. Among the conventional wheat antigens, glutenins induced highest histamine release from basophils of patients with HWP-WDEIA. The sensitivities of patients against glutens and glutenins were reduced over months along with the discontinuance of HWP-soap.

CONCLUSIONS

The development of HWP-WDEIA is associated with the use of HWP-soap. The sensitivities to HWP that cross reacts with non-processed wheat may be reduced or possibly cured after the discontinuation of HWP-soap.

[Asthma and baker's allergy: experience with health programs]

Wheat flour sensitization may lead to several occupational diseases: persistent rhinitis, intermittent or persistent asthma, conjunctivitis, urticaria, and contact dermatitis. The main allergenic components of wheat have been identified, the prevalent mechanism is IgE-mediated, the worsening after starting of sensitization shows the characters of the "allergy march" till the respiratory functional impairment and disability. Nowadays the occupational rhinitis is the first important step to begin to start prevention, but its relevance is also for quality of life of subjects. Data about the prevalence of the sensitization in Italy seem to be spread, ranging from 4% to 24% in the literature and till 32% in a recent our investigation. A complete and early diagnosis is essential to manage the allergic bakers, aiming relocation in their own activity. A specific immunotherapy by allergenic vaccine has been studied and it is now possible. In our experience 43 bakers and pastry makers were treated by the same vaccine (Lofarma Laboratories, Milan) and revalued after many years; 83% were still at work and 70% claimed only poor or no-symptoms during work, in any way with a tolerable condition. At present the baker's disease may be managed by included interventions "man-environment" avoiding the extreme choice of leaving the working activity. The Lombardy Government published specific Guide Lines on the prevention and proposed a planned project for three years, to be adopted according to local needs in collaboration with the public health service.

The effect of past food avoidance due to allergic symptoms on the growth of children at school age

BACKGROUND

The influence of food avoidance due to allergic symptoms in infancy on the growth of children at school age has not been well evaluated.

METHODS

To determine the growth of schoolchildren who avoided eggs, milk, or wheat due to immediate allergic symptoms in infancy (food avoiders in infancy) (FAI), a questionnaire on the presence of allergic diseases, as well as present height and weight, was administered to the parents of 14,669 schoolchildren. 11,473 subjects had available data. The height and weight standard deviation scores (HtSDS and WtSDS) and body mass index percentile (BMI percentile) of each subject were calculated.

RESULTS

FAI had significantly lower WtSDS than non-FAI (P = 0.01). Among those with avoidance at age 3 years, those who avoided two or more foods and those who avoided milk had significantly lower HtSDS than their counterparts (P = 0.02 and 0.04, respectively). FAI had a significantly lower prevalence of obesity (P = 0.01) and overweight (P = 0.002), while there was no difference in the prevalence of underweight (P = 0.58), resulting in a significantly higher prevalence of appropriate weight (P = 0.01) compared to non-FAI. Significantly lower prevalence of obesity and overweight was observed even among those who terminated the avoidance by age 3 years.

CONCLUSIONS

FAI were less likely to be obese or overweight, resulting in a higher prevalence of appropriate weight at school age. Further investigation should contribute to better management of food allergy and obesity.

Infant and childhood diet and type 1 diabetes risk: recent advances and prospects

Type 1 diabetes is a chronic autoimmune disease characterized by a preclinical period of autoimmunity. It is well accepted that both genetic and environmental factors contribute to disease risk. Given that type 1 diabetes, and its preclinical autoimmunity, appear early in life, infant and childhood diet have been implicated as potential initiating exposures in the etiology of the disease. Several publications in the past year have provided further evidence for existing hypotheses regarding the roles of wheat, cow's milk, omega-3 fatty acids, and the maternal diet during pregnancy. However, inconsistencies in findings between studies suggest the need for collaboration and standardization of study methods to move forward in research in this area. One such example of this is the TEDDY (The Environmental Determinants of Diabetes in the Young) study, which is an international, multicenter birth cohort study with standardized recruitment, dietary collection methodologies, and analytic approaches.

Study of pulmonary (lung) functioning of commercial wheat grinding machine operators in India using spirometric testing

In ancient times, in India each household had a chakki to mill the wheat. There was no concept of getting wheat grounded from outside. With the fast changing lifestyle, this tradition has almost disappeared now. Today every city of India has numerous commercial wheat grinding machine shops located at various places. Other than states like Punjab, this occupation is mostly unorganized and little has been done to look into the welfare and health of these machine operators. Like most of the occupations, this occupation of wheat grinding also has several occupational hazards and injuries associated with it. The most obvious of them all in this case is due to the continuous exposure of the operators to the rising dust wheat particles, commonly called atta). This perpetual inhaling ofpollutants exposes the operators to risks of pulmonary malfunctioning. Therefore, this paper attempts to determine the pulmonary functioning of the commercial wheat grinding machine operators in India using spirometric testing. On the basis of the anthropometric data, effort has been done to develop the expected lung performance. Further, the actual lung performance of the operators is measured and compared with expected performance.