Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands.
PLoS One. 2010 Dec 16;5(12):e15637. doi: 10.1371/journal.pone.0015637.
Celiac disease is caused by an uncontrolled immune response to gluten, a heterogeneous mixture of wheat storage proteins, including the α-gliadins. It has been shown that α-gliadins harbor several major epitopes involved in the disease pathogenesis. A major step towards elimination of gluten toxicity for celiac disease patients would thus be the elimination of such epitopes from α-gliadins. We have analyzed over 3,000 expressed α-gliadin sequences from 11 bread wheat cultivars to determine whether they encode for peptides potentially involved in celiac disease. All identified epitope variants were synthesized as peptides and tested for binding to the disease-associated HLA-DQ2 and HLA-DQ8 molecules and for recognition by patient-derived α-gliadin specific T cell clones. Several specific naturally occurring amino acid substitutions were identified for each of the α-gliadin derived peptides involved in celiac disease that eliminate the antigenic properties of the epitope variants. Finally, we provide proof of principle at the peptide level that through the systematic introduction of such naturally occurring variations α-gliadins genes can be generated that no longer encode antigenic peptides. This forms a crucial step in the development of strategies to modify gluten genes in wheat so that it becomes safe for celiac disease patients. It also provides the information to design and introduce safe gluten genes in other cereals, which would exhibit improved quality while remaining safe for consumption by celiac disease patients.
乳糜泻是由针对麸质的失控免疫反应引起的，麸质是小麦储存蛋白的一种不均匀混合物，包括α-麦醇溶蛋白。已经表明，α-麦醇溶蛋白含有几个参与疾病发病机制的主要表位。因此，消除乳糜泻患者的麸质毒性的重要步骤是从α-麦醇溶蛋白中消除这些表位。我们分析了来自 11 种面包小麦品种的 3000 多个表达的α-麦醇溶蛋白序列，以确定它们是否编码可能与乳糜泻有关的肽。所有鉴定的表位变体均被合成肽，并测试其与疾病相关的 HLA-DQ2 和 HLA-DQ8 分子的结合能力，以及与患者来源的α-麦醇溶蛋白特异性 T 细胞克隆的识别能力。对于涉及乳糜泻的每个α-麦醇溶蛋白衍生肽，都确定了几个特定的天然存在的氨基酸取代，这些取代消除了表位变体的抗原特性。最后，我们在肽水平上提供了原理证明，通过系统引入这种天然存在的变异，可以产生不再编码抗原肽的α-麦醇溶蛋白基因。这是开发在小麦中修饰谷蛋白基因以使其对乳糜泻患者安全的策略的重要步骤。它还提供了设计和引入其他谷物中安全谷蛋白基因的信息，这些基因在保持对乳糜泻患者安全的同时，还具有改善的质量。
