ATLA::Alternatives to Laboratory Animals

Volume 24, Number 1

Toxicity of bread wheat lines lacking prolamins encoded by the Gli-B1/Bli-B5/Glu-B3 and Gli-D1/Glu-D3 loci in coeliac disease as determined by their agglutinating activity.

ATLA 24, 39-48, January/February 1996

Massimo De Vincenzi,1 Maria R. Dessí1 Roberto Luchetti,1 Norberto Pogna,2 Rita Redaelli3 and Giovanni Galterio2

1Laboratorio di Metabolismo e Biochimica Patologica, Istituto Superiore di Sanitá, Viale Regina Elena 299, 00161 Rome, Italy; 2Istituto Sperimentale Cerealicoltura, Via Cassia 176, 00191 Rome, Italy; 3Istituto Sperimentale Cerealicoltura, Via Mulino 3, 20079 S. Angelo Lodigiano, Italy

SUMMARY

Peptic-tryptic (PT) digests of alcohol-soluble proteins from the flour of three mutant lines of bread wheat, lacking y-gliadins, w-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 for 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 a-gliadins, which constituted about 19% of the gliadins in the S. Pastore and Alpe 1 I cultivars, 24.5% in the S. Pastore 4A and Alpe 1 I- null lines, and 34.8% in the double mutant line, DM 22166, as determined by densitometric scanning of their acid polyacrylamide gel electrophoresis patterns. The minimal concentrations of PT digest required to agglutinate 100% of K562(S) cells were 73 mg/l and 96 mg/l, in the S. Pastore and Alpe 1 I cultivars, respectively, compared with 146 mg/l, 138mg/l and 200 mg/l in the "null" lines, S. Pastore 4A Alpe 1 I- and DM 22166, respectively. The results indicated that proteins other than a-gliadins are involved in the gluten-sensitive enteropathy.

Keywords: coeliac disease, gliadin, glutenin subunits, mutant lines, toxicity