An inter-laboratory study with 15 participating laboratories was performed to determine the performance characteristics of a rapid and simple competitive DQ2.5-glia-alpha 3 Gliadin ELISA for the... Show moreAn inter-laboratory study with 15 participating laboratories was performed to determine the performance characteristics of a rapid and simple competitive DQ2.5-glia-alpha 3 Gliadin ELISA for the detection of gluten in food. The ELISA test kit used in this study was previously validated in an infra-laboratory study showing excellent performance for determination of gluten in processed foodstuffs such as sauces, soups and beers. The participants of the inter-laboratory study obtained 20 samples and were asked to analyse them in accordance with the ELISA's manual. The samples included in this study were oats and gluten-free tomato soup powder spiked with gliadin standard obtained from the Working Group on Prolamin Analysis and Toxicity and 12 wheat starch samples naturally contaminated with gluten. The spiked samples were prepared by adding 10, 50 and 100 ppm of gliadin, what corresponds to 20, 100 and 200 ppm of gluten, respectively. Non-spiked samples were also provided. The spiking levels were chosen to test the ELISA performance with samples containing gluten at the concentrations relevant for the labelling requirements. In accordance with Commission Implementing Regulation 828/2014 foodstuffs containing maximum of 20 ppm and 100 ppm can be labelled "gluten-free" and "very low gluten", respectively. In case of spiked samples, the participants obtained average recoveries of PWG.gliadin from spiked oats and gluten-free tomato soup powder of 84.8-102.8% and 88.6-103.5% at all 3 spiking levels respectively. There was also a good agreement between the average results obtained in this study, LC-MS-MRM results and R5 sandwich ELISA reference method results for naturally contaminated wheat starch samples. This inter-laboratory study demonstrated the applicability of DQ2.5-glia-alpha 3 Gliadin ELISA for the quantitative screening of foodstuffs for the presence of gluten. Show less
Celiac disease is caused by an abnormal intestinal T cell response to cereal gluten proteins. The disease has a strong human leukocyte antigen (HLA) association, and CD4(+) T cells recognizing... Show moreCeliac disease is caused by an abnormal intestinal T cell response to cereal gluten proteins. The disease has a strong human leukocyte antigen (HLA) association, and CD4(+) T cells recognizing gluten epitopes presented by disease-associated HLA-DQ allotypes are considered to be drivers of the disease. This paper provides an update of the currently known HLA-DQ restricted gluten T cell epitopes with their names and sequences. Show less
Celiac disease is an intolerance to dietary gluten in genetically predisposed individuals, leading to alterations of the small bowel mucosa. The treatment consists of a life-long, gluten-free diet.... Show moreCeliac disease is an intolerance to dietary gluten in genetically predisposed individuals, leading to alterations of the small bowel mucosa. The treatment consists of a life-long, gluten-free diet. The aims of this thesis were to measure some of the environmental factors considered to play a role in the prevention of celiac disease. For that purpose breast milk was studied on the presence of glutenpeptides and a food frequency questionnaire was developed and validated to quantify gluten intake in young infants. Furthermore, the current treatment at different ages and the ability to develop gluten tolerance were studied. It became clear that the nutrient intake of adolescents on a gluten-free diet can be ameliorated, and that the rather new naturally gluten-free cereal tef is frequently used by Dutch celiac patients and a wide majority of them can consume tef without clinical symptoms. Therefore tef can be a valuable addition to their diet. Although celiac disease is considered to be a permanent condition, we made an attempt to find patients who have become tolerant to gluten. We found 2 of these exceptional patients and found that one of them had HLA-typing different from HLA-DQ2/DQ8, suggesting that genetic factors may play a role in the development of tolerance. The underlying mechanisms leading to prevention, disease development or tolerance to gluten are complex and need to be further studied. Show less
