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
Gluten diet and a self-diagnosis of gluten sensitivity. People with NCGS may develop gastrointestinal symptoms, which resemble those of irritable bowel syndrome or wheat allergy, or a wide variety of non-gastrointestinal symptoms, such as headache, chronic fatigue, fibromyalgia, atopic diseases, allergies, neurological diseases, or psychiatric disorders, among others. Besides gluten, additional components present in wheat, rye, barley, oats, and their derivatives, including other proteins called ATIs and short-chain carbohydrates known as FODMAPs, may cause NCGS symptoms. The effects of FODMAPs are only limited to gastrointestinal mild discomfort. ATIs may cause toll-like receptor 4 (TLR4)-mediated intestinal inflammation in humans. People can also