Celiac.com 06/22/2015 - Currently available digestive enzymes do not fully degrade gluten, and are thus of questionable use for people with celiac disease or gluten intolerance, say a team of researchers. Prior research had shown that post-proline cutting enzyme effectively degrade the immunogenic gluten peptides. Several existing digestive enzyme supplements claim to promote gluten degradation.
For their study, they assessed five commercially available digestive enzyme supplements along with purified digestive enzymes. They assessed these enzymes using enzyme assays and mass spectrometric identification. They monitored gluten epitope degradation using R5 ELISA, mass spectrometric analysis of the degradation products, and T cell proliferation assays.
They found that the enzyme supplements leave the nine immunogenic epitopes of the 26-mer and 33-mer gliadin fragments largely intact. This is due to the high proline content of gluten molecules, which prevents gastrointestinal proteases from fully degrading them, leaving large proline-rich gluten fragments intact, including an immunogenic 33-mer from α-gliadin and a 26-mer from γ-gliadin.
These latter peptides can trigger pro-inflammatory T cell responses resulting in tissue remodeling, malnutrition and a variety of other complications.
In contrast, the pure enzyme AN-PEP effectively degraded all nine epitopes in the pH range of the stomach at much lower dose.
From these results, the team concludes that currently available digestive enzyme supplements are ineffective in degrading immunogenic gluten epitopes.