Mutational analysis of major, sequential IgE-binding epitopes in αs1-casein, a major cow's milk allergen
Mutational analysis of major, sequential IgE-binding epitopes in αs1-casein, a major cow's milk allergen
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DOI：
10.1067/mai.2003.1617
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发表时间：
2003-08-01
影响因子：
14.2
通讯作者：
Beyer, K
中科院分区：
文献类型：
--
作者：
Cocco, RR;Järvinen, KM;Beyer, K
背景：牛奶过敏在儿童早期很常见，除了避免牛奶过敏外，没有其他治疗方法。在小鼠模型的花生过敏，免疫治疗与突变，工程，蛋白质出现prospected.Objective：我们试图确定的关键氨基酸（AAs）内的α（S1）-酪蛋白，一个主要的牛奶过敏原的主要B细胞表位的免疫球蛋白E（IgE）结合。这将提供必要的信息来改变的cDNA编码的蛋白质能够激活牛奶特异性T细胞，但降低IgE结合capability.Methods：IgE结合表位的突变分析，10-14 AA长度的肽合成上衍生的纤维素膜与单个或多个AA取代。膜免疫标记与汇集的血清从15牛的牛奶过敏的患者和8个人serum.Results：与汇集的血清，取代一个单一的AA导致完全废除IgE结合到2的8肽和减少结合在其余的。多个AA的取代导致剩余肽中结合的废除。在8种肽中的4种中，用合并血清鉴定的关键AA未导致与I个或多个个体患者的IgE结合显著降低。对于这些患者，其他关键的氨基酸被确定，表明在IgE recognition.Conclusion更异质性的模式：这项研究表明，单个或多个AA取代IgE结合表位内的结果减少结合牛奶特异性IgE抗体的患者的血清。然而.对于将来用突变肽进行的免疫干预，关键的AA应该用个体患者血清进行评估，以确定B细胞表位的异质性。
Background: Allergy to cow's milk is common in early childhood, and no therapy other than avoidance exists. In murine models of peanut allergy, immunotherapy with mutated, engineered, proteins appears promising.Objective: We sought to identify the critical amino acids (AAs) for immunoglobulin E (IgE) binding within the major B-cell epitopes of alpha(S1)-casein, a major cow's milk allergen. This will provide the necessary information to alter the cDNA to encode a protein capable of activating milk-specific T cells, but with reduced IgE-binding capacity.Methods: For mutational analysis of the IgE-binding epitopes, peptides of 10-14 AAs in length were synthesized on a derivatized cellulose membrane with single or multiple AA substitutions. Membranes were immunolabeled with pooled sera from 15 cow's-milk-allergic patients and with 8 individual sera.Results: With the pooled sera, substitution of a single AA led to complete abrogation of IgE binding to 2 of 8 peptides and diminished binding in the remainder. Substitution of multiple AAs led to an abrogation of binding in the remaining peptides. In 4 of the 8 peptides, the critical AA identified with pooled sera did not result in significant reduction of IgE binding with I or more individual patients. For these patients, other critical AAs were identified, indicating a more heterogeneous pattern in IgE recognition.Conclusion: This study indicates that single or multiple AA substitutions within IgE-binding epitopes result in reduced binding of milk-specific IgE antibodies by patients' sera. However. for future immunotherapeutic interventions with mutated peptides, critical AAs should be evaluated with individual patient sera to determine B-cell-epitope heterogeneity.