Gluten immunogenic peptides (GIP)

Gluten immunogenic peptides (GIP) are fragments of gluten proteins, primarily gliadin, that remain undigested by human gastrointestinal enzymes due to their high proline and glutamine content. The most prominent of these is the 33-mer alpha-gliadin peptide, which is highly resistant to proteolysis and contains multiple overlapping T-cell epitopes. In individuals with Celiac disease, these peptides pass through the intestinal epithelium and are deamidated by tissue transglutaminase (tTG2), significantly increasing their affinity for HLA-DQ2 or HLA-DQ8 molecules on antigen-presenting cells. This interaction triggers an inflammatory T-cell response, leading to villous atrophy and malabsorption. Therapeutic strategies targeting GIP include the use of oral digestive enzymes (glutenases) to degrade the peptides in the stomach before they reach the small intestine, or sequestering agents to prevent their absorption.

Other names

33-mer gliadin peptideGliadin-derived peptidesToxic gluten peptidesAlpha-gliadin 33-merp56-88 peptidep31-43 peptide

Enzymatic degradation of immunogenic gluten peptides into non-toxic fragments in the gastrointestinal tract or sequestration to prevent immune activation.