Reaction of spice proteins with serum antibodies from celiac patients and rabbit antibodies raised to specific glutamine/proline-containing peptides

The aim of this study was to determine if extracts from selected spices (caraway, ginger, chili, sweet peppers, anise, sesame, nutmeg and black pepper) might be harmful to people suffering from celiac disease, wheat allergy or non-celiac gluten sensitivity. All of these spice extracts exhibited some reaction to antibodies found in sera from two celiac patients and to sera from rabbits that had been sensitized with the specific peptides, QQQPP, PQQQ and QQQP. These peptides had sequences that might be included in active epitopes for celiac disease and wheat allergy. Methodology followed in this study included ELISA, SDS-PAGE and immunoblotting. The observed reactivities suggest that spice proteins might produce adverse reactions in celiac patients, patients with various wheat allergies or with non-celiac gluten sensitivity. However, further work would be needed to elucidate this possibility.