Gluten immunochemistry motif", which is found in wheat and other "Triticeae" genera.(see also: ). Alpha-2 secalin, the glutinous protein in rye, is composed of two amino-terminal overlapping T-cell sites at positions (8-19) and (13-23). Although T-cell responses to many prolamins can be found in coeliac disease, one particular gliadin, α2-gliadin appears to be the focus of T-cells. These responses were dependent on prior treatment with tissue transglutaminase. Α2-gliadin differs from the other α-gliadins, specifically because it contains an insert of 14 amino acids. This particular insertion creates 6 T-cell sites where, in the most similar gliadins, there are 2 or less sites.
Gluten immunochemistry include: LTP (albumin/globulin), thioredoxin-hB, and wheat flour peroxidase. A particular 5 residue peptide, Gln-Gln-Gln-Pro-Pro motif, has been found to be a major wheat allergen. New immunogenic motifs appear in the literature almost monthly and new gliadin and "Triticeae" protein sequences appear that contain these motifs. The HLA DQ2.5 restricted peptide "I I Q P Q Q P A Q" produced approximately 50 hits of identical sequences in NCBI-Blast search is one of a several dozen known motifs whereas only a small fraction of Triticeae gluten variants have been examined. For this reason the immunochemistry is best discussed at the level