TOXICITY OF BREAD WHEAT LINES LACKING PROLAMINS ENCODED BY THE GLI-B1GLI-B5/GLU-B3 AND GLI-D1/GLU-D3 LOCI IN CELIAC-DISEASE AS DETERMINED BY THEIR AGGLUTINATING ACTIVITY/

Peptic-tryptic (PT) digests of alcohol-soluble proteins from the flour of three mutant lines of bread wheat, lacking gamma-gliadins, <(omega )over bar>-gliadins and low molecular-weight glutenin subunits encoded by the Gli-B1/Gli-B5/Glu-B3 loci (line S. Pastore 4A), the Gli-D1/Glu -D3 loci (line Alpe 1 I-) or both groups of loci (line DM 22166), were compared with those of the normal cultivars S. Pastore and Alpe 1 I f or their agglutinating activities on human myelogenous leukemia K562(S ) cells, agglutination being strongly associated with toxicity for the coeliac intestine. All of the genotypes tested contained A-type alpha -gliadins, which constituted about 19% of the gliadins in the S. Pasto re and Alpe 1 I cultivars, 24.5% in the S. Pastore 4A and Alpe 1 I- nu ll lines, and 34.8% in the double mutant line, DM 22166, as determined by densitometric scanning of their acid polyacrylamide gel electropho resis patterns. The minimal concentrations of PT digest required to ag glutinate 100% of K562(S) cells were 73 mg/l and 96 mg/l, in the 8. Pa store and Alpe 1 I cultivars, respectively, compared with 146 mg/l, 13 8 mg/l and 200 mg/l in the ''null'' lines, S. Pastore 4A, Alpe 1 I- an d DM 22166, respectively. The results indicated that proteins other th an cc-gliadins are involved in the gluten-sensitive enteropathy.