Gluten immunochemistry to react with gamma gliadin to a degree comparable to DQ2.5. T-cell responses to the high molecular weight glutenin may be more important with DQ8 mediated than DQ2.5 mediated celiac disease. Antibody recognition of gluten is complex. Direct binding to gluten such as anti-gliadin antibodies has an ambiguous pathogenesis in coeliac disease. The crosslinking of gliadin with tissue transglutaminase leads to the production of anti-transglutaminase antibodies, but this is mediated through T-cell recognition of gliadin. The allergic recognition of gliadin by mast cells, eosinophiles in the presence of IgE has notable direct consequences, such as exercise-induced anaphylaxis. Anti-gliadin antibodies, like
Gluten "generally recognized as safe" (GRAS). In August 2013, the FDA issued a final ruling, effective August 2014, that defined the term "gluten-free" for voluntary use in the labeling of foods as meaning that the amount of gluten contained in the food is below 20 parts per million. Gluten Gluten (from Latin "gluten", "glue") is a composite of storage proteins termed prolamins and glutelins that is stored together with starch in the endosperm (which nourishes the embryonic plant during germination) of various cereal (grass) grains. It is found in wheat, barley, rye, oats and related species and hybrids (such as spelt,