In contrast, the R5 antibody was raised against a secalin extract; later, the epitope it reacts with was identified as the QQPFP pentapeptide. The distinction between the two antibodies relates to the fact that the G12 antibody specifically targets the toxic fragment that triggers the autoimmune reaction in celiac patients rather than a peptide sequence unrelated to clinical outcomes. It was confirmed during validation studies that G12 does not give false positive signals with soy and is suitable for measuring gluten in products containing soy. There is also no cross reactivity to maize or rice.
There is an ongoing debate about whether or not oats are safe. Several publications have concluded that certain oat varieties may cause an autoimmune response in celiac patients. During the validation of the AgraQuant Gluten G12 ELISA test and the AgraStrip Gluten G12 Lateral Flow Test, positive and negative responses to oat varieties were observed. The positive results appear to be a specific reaction of the antibody with the toxic fragment rather than a nonspecific response. Therefore, the G12 antibody may shed new light on this debate by recognizing oat varieties that trigger a response in celiac patients. The Spanish Celiac Association recently awarded the 6th National Prize for Research on Celiac Disease to a scientific team that used the G12 antibody to identify oat varieties containing low levels of gluten.
Celiac patients depend on the correct labeling of gluten-free food to maintain their health. Ensuring the safety of food is a demanding task, fueling new developments in detection methods for gluten. Results obtained from new immunochemical test systems based on the G12 antibody should be considered closer to the ideal of a food safety test, because they establish the important link between celiac disease and the detection of the immunotoxic peptides.
Elisabeth Hammer is a product manager with Romer Labs.