Anti-transglutaminase antibodies antigen, presented by MHC molecules (HLA in humans) on antigen-reactive B-cells. These T-helper cells then stimulate B-cells to multiply and mature into plasma cells that make IgA and IgG to that protein. In the case of celiac disease, the current understanding is that tTG autoimmunity arises when T-cells are generated against wheat gliadin and similar gluten proteins made by a class of grasses called "Triticeae", which includes wheat (See Wheat taxonomy), barley, and rye. The T-cells are defined by the ability to react to HLA-DQ8 and DQ2.5 restricted antigens and gliadin is one of the antigens. Gliadin is a favored
Non-celiac gluten sensitivity in gluten and gluten-containing cereals (wheat, rye, barley, and their derivatives) may have a role in the development of symptoms. FODMAPs are present in gluten-containing grains and have recently been identified as a possible cause of gastrointestinal symptoms in NCGS patients, but do not justify extra-digestive symptoms. For these reasons, NCGS is a controversial clinical condition and some authors still question it. It has been suggested that "non-celiac wheat sensitivity" is a more appropriate term, without forgetting that other gluten-containing cereals are implicated in the development of symptoms. NCGS is the most common syndrome of gluten-related disorders with prevalence rates