DQ2.2 confers adaptive immunity to gliadin permitting coeliac disease. Rye flour is high in gliadin but low in glutenin. In disease, transglutaminase reacts with gliadin forming a linkage. These tightly linked glutenin subunits associate more loosely, along with gliadin, into larger gluten aggregates. Clinically these antibodies and IgG antibodies to gliadin are abbreviated as AGA. In forming this bond transglutaminase becomes linked to T-cell epitopes on gliadin. Deamidated gliadin is produced by acid or enzymatic treatment of gluten. Specific amino acid sequences within the gliadin proteins are responsible for this activity. The best known storage protein in wheat is the prolamin gliadin, a component of gluten. Th1 cells reactive towards gliadin have been discovered, but none against tTG. The latter case yields a permanently covalently linked complex between the gliadin and the tTg. The LMW ones are similar to Gliadin. This, however, could interfere with the effects that gliadin has on the quality of dough. Gliadin peptides cross the intestinal barrier by active transport.