A Food-Grade Enzyme Preparation with Modest Gluten Detoxification Properties
Figure 9
Stimulation of T-cell lines derived from biopsies of celiac sprue patients with gluten digested by aspergillopepsin (ASP) and dipeptidyl peptidase IV (DPPIV).
Whole gluten powder (15 mg/ml) mixed with casein (50 mg/ml) was incubated with either 0.6 mg/ml pepsin or 0.35 mg/ml ASP and 0.7 mg/ml DPPIV. The digestions were initiated in 0.03 M HCl and 3 mg/ml CaCO3, and every 5 min additional HCl was added. After digestion for 60 min at 37°C, the samples were further treated with 0.375 mg/ml trypsin and 0.375 mg/ml chymotrypsin for 30 min at pH 6.0. The immunotoxic peptide content in the water-soluble fraction of the digests was measured by a T-cell proliferation assay. A stimulation index of 1 indicates background levels of T-cell proliferation and is denoted with a horizontal line. The name of the individual T-cell lines is indicated in the graph.