Gliadin antibodies

Gliadin-Ak are antibodies (IgA or IgG antibodies) which are directed against the (native = unchanged) gliadin (storage proteins of wheat) ingested with food.

Gluten makes up about 80% of the total protein in wheat and consists of several fractions, including the proteins gliadin and glutenin.

Gliadin antibodies are not autoantibodies because they are not directed against the body's own structures, but against specific protein structures in the grain: Gliadin - is a protein component of thegluten protein in the grain. These antibodies are closely related to celiac disease and dermatitis herpetiformis.

Together with the determination of auto-Ac (IgA) against transglutaminase antibodies (tTG) or endomysium antibodies (EMA), the auto-Ac (IgA) against gliadin have the highest diagnostic significance in celiac disease. Under a strict gluten-free diet, there is a drop in gliadin antibody titers. There is a high association of celiac disease with HLA-DQw2 (over 95%), HLA-DR3, DR5 or DR7 (98%).

If symptoms suspicious for celiac disease are present, antibodies to tissue transglutaminase IgA, deaminated gliadin peptides (IgG), and total IgA are tested. If the transglutaminase IgA antibodies are negative, a gluten-sensitive enteropathy is largely excluded in symptomatic patients. A prerequisite for the test is a sufficiently gluten-containing diet in the preceding period, as the specific antibodies can fall below the detection limit during a successful gluten-free diet.