Performance assessment of a new G12/A1 antibody-based rapid ELISA using commercially available and gluten-spiked food samples

OBJECTIVE

Food products with <20 mg/kg gluten can be labeled 'gluten-free' according to international regulations. Several antibodies-based ELISAs have been develop to track gluten traces in food products. Among them, R5 and G12 antibody-based ELISAs are the frequently used methods. However, these antibodies have certain limitations. We evaluated the accuracy of G12/A1 antibody-based 'Glutentox ELISA Rapid G12' and compared the results with the current reference method i.e., R5 antibody-based 'Ridascreen R5 ELISA'.

METHODS

In the first step, the performance of Glutentox ELISA Rapid G12 kit was inspected by determination of the threshold value i.e., > or <20 mg/kg gluten in different food products. In the second step, quantification accuracy was assessed by quantification of gluten in gluten-free food products spiked with gliadin reference material.

RESULTS

In total 47 food products (naturally and labeled gluten-free, and food with traces of gluten) were included. Of them, 29 products were quantified with <20 mg/kg, and 18 with a low level of gluten by both the kits. Six out of 29 gluten-free products were used for the recovery test at different spike levels. Gluten concentration and mean recovery rates of individual kits showed consistency.

CONCLUSION

GlutenTox Rapid G12 ELISA could be an appropriate choice for detecting gluten in food products but needs more in-house validation and collaborative tests.

Vitamin D status in healthy Italian school-age children: a single-center cross-sectional study

BACKGROUND

Vitamin D is involved in calcium homeostasis and bone metabolism, although its extra-skeletal actions are also well-known. Low serum 25(OH)D levels are common both in adults and children worldwide.

METHODS

The purpose of this cross-sectional study was to determine the distribution of 25(OH)D levels in a cohort of healthy Italian school-age children, aged 5-10 years, in relationship to determinants of vitamin D deficiency such as season, BMI, gender, age and ethnicity.

RESULTS

The mean serum 25(OH) D level was 28.2 ng/mL; the prevalence of 25(OH)D sufficiency (> 30 ng/mL), insufficiency (20-30 ng/mL), deficiency (10-20 ng/mL) and severe deficiency (< 10 ng/mL) was 36%, 37%, 21% and 6% of the study-group population, respectively. The lower serum 25(OH)D values were observed during winter (21.6 ng/mL) and spring (22.9 ng/mL), as compared to summer (46.7 ng/mL) (p < 0.001). Higher BMI z-scores were associated with lower 25(OH)D level while no statistical difference was observed as related to gender and age groups.

CONCLUSIONS

Healthy Italian schoolchildren show low 25(OH)D levels, particularly during winter and spring time. Seasonality, ethnicity and overweight/obesity were confirmed to influence the vitamin D status, thus indicating the need for effective initiatives to support adequate vitamin D status in this population group.

Determination of Urinary Gluten Immunogenic Peptides to Assess Adherence to the Gluten-Free Diet: A Randomized, Double-Blind, Controlled Study

INTRODUCTION

The adherence to a gluten-free diet (GFD) is a trending topic in the management of celiac disease. The aim of our study was to evaluate the diagnostic performance of urinary gluten immunogenic peptides (GIP) determination to detect gluten contamination of the GFD.

METHODS

In study A, 25 healthy adults on a standard GFD performed 6 gluten challenges (0, 10, 50, 100, 500, and 1,000 mg) with quantification of urinary GIP before (T0) and during the following 24 hours. In study B, 12 participants on a gluten contamination elimination diet underwent urinary GIP determination at T0 and after challenge with 5 or 10 mg gluten. Urine GIP concentration was determined by an immunochromatographic assay.

RESULTS

In study A, 51 of 150 baseline urine samples were GIP+ on GFD and 7 of 17 were GIP+ after the zero-gluten challenge, whereas only 55 of 81 were GIP+ after the 10-1,000 mg gluten challenges. There was no significant change in the 24-hour urinary GIP when increasing gluten from 10 to 1,000 mg. In study B, 24 of 24 baseline urine samples were GIP-, whereas 8 of 24 were GIP+ after 5 or 10 mg of gluten.

DISCUSSION

Traces of gluten in the standard GFD may cause positivity of urinary GIP determination, whereas a false negativity is common after a gluten intake of 10-1,000 mg. Owing to the impossibility of standardizing the test in normal conditions, it seems unlikely that urinary GIP determination may represent a reliable tool to assess the compliance to the GFD of patients with celiac disease or other gluten-related disorders.

Current Status and Perspectives on the Application of CRISPR/Cas9 Gene-Editing System to Develop a Low-Gluten, Non-Transgenic Wheat Variety

Wheat gluten contains epitopes that trigger celiac disease (CD). A life-long strict gluten-free diet is the only treatment accepted for CD. However, very low-gluten wheat may provide an alternative treatment to CD. Conventional plant breeding methods have not been sufficient to produce celiac-safe wheat. RNA interference technology, to some extent, has succeeded in the development of safer wheat varieties. However, these varieties have multiple challenges in terms of their implementation. Clustered Regularly Interspaced Short Palindromic Repeats-associated nuclease 9 (CRISPR/Cas9) is a versatile gene-editing tool that has the ability to edit immunogenic gluten genes. So far, only a few studies have applied CRISPR/Cas9 to modify the wheat genome. In this article, we reviewed the published literature that applied CRISPR/Cas9 in wheat genome editing to investigate the current status of the CRISPR/Cas9 system to produce a low-immunogenic wheat variety. We found that in recent years, the CRISPR/Cas9 system has been continuously improved to edit the complex hexaploid wheat genome. Although some reduced immunogenic wheat varieties have been reported, CRISPR/Cas9 has still not been fully explored in terms of editing the wheat genome. We conclude that further studies are required to apply the CRISPR/Cas9 gene-editing system efficiently for the development of a celiac-safe wheat variety and to establish it as a "tool to celiac safe wheat".

The Clinical Spectrum of Inflammatory Bowel Disease Associated With Specific Genetic Syndromes: Two Novel Pediatric Cases and a Systematic Review

Background and Aims: Inflammatory bowel disease (IBD) is a typical polygenic disorder and less frequently shows a monogenic origin. Furthermore, IBD can originate in the context of specific genetic syndromes associated with a risk of autoimmune disorders. We aimed to systematically evaluate the prevalence of IBD in specific genetic syndromes and to review the clinical characteristics of the published cases. Methods: According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, studies describing patients with IBD and a genetic syndrome and/or studies indicating the prevalence or incidence of IBD in subjects with a genetic syndrome were included. Results: Forty-six studies describing a total of 67 cases of IBD in six genetic syndromes and two personally assessed unpublished cases were included in the review. The majority of cases were associated with Turner syndrome (TS) (38 cases), Down syndrome (DS) (18 cases) and neurofibromatosis type 1 (NF1) (8 cases). Sporadic cases were described in DiGeorge syndrome (2), Kabuki syndrome (2), and Williams syndrome (1). The prevalence of IBD ranged from 0.67 to 4% in TS and from 0.2 to 1.57% in DS. The incidence of IBD was increased in TS and DS compared to the general population. Eight cases of IBD in TS had a severe/lethal course, many of which described before the year 2000. Two IBD cases in DS were particularly severe. Conclusion: Evidence of a greater prevalence of IBD is accumulating in TS, DS, and NF1. Management of IBD in patients with these genetic conditions should consider the presence of comorbidities and possible drug toxicities. Systematic Review Registration: PROSPERO, identifier: CRD42021249820.

Lower Level of Plasma 25-Hydroxyvitamin D in Children at Diagnosis of Celiac Disease Compared with Healthy Subjects: A Case-Control Study

OBJECTIVE

To evaluate the vitamin D status of children with a new diagnosis of celiac disease compared with healthy controls.

STUDY DESIGN

This was a case-control study. Cases were consecutive children with newly diagnosed celiac disease. Controls were healthy children matched for age, sex, ethnicity, and month of blood testing. Plasma 25-hydroxyvitamin D (25-OHD) was measured as the index of vitamin D nutritional status. The Student t test was used for comparisons. Differences in frequencies were evaluated with the χ² test. Associations between variables were estimated by calculating Pearson correlation coefficients.

RESULTS

There were 131 children with celiac disease enrolled (62% females; mean age 8.1 ± 1.1 years). The control group included 131 healthy children (62% females; mean age 8.2 ± 1.2). All were of European origin. Plasma 25-OHD levels were significantly lower in patients than in controls (25.3 ± 8.0 and 31.6 ± 13.7 ng/mL; P < .0001). The percentage of children with vitamin D deficiency (<20 ng/mL) was significantly higher in children with celiac diseaseas compared with controls (31% vs 12%; P < .0001). The concentration of 25-OHD was significantly lower in patients than in controls during summer (P < .01) and autumn (P < .0001).

CONCLUSIONS

In this case-control study, at diagnosis, children with celiac disease showed lower levels of plasma 25-OHD compared with healthy subjects. Vitamin D status should be checked at diagnosis of celiac disease, particularly during summer and fall months.