中文摘要：

α-乳白蛋白是引起牛乳过敏的主要过敏原之一。识别α-乳白蛋白作用表位及影响致敏性的关键氨基酸，对于揭示α-乳白蛋白致敏机理及低致敏乳制品的开发具有重要的意义。本研究采用固相合成技术合成α-乳白蛋白系列多肽，以牛乳过敏患者血清为探针，通过酶联免疫吸附分析法识别α-乳白蛋白的作用表位和关键氨基酸。结果表明：免疫球蛋白（immunoglobulins，Ig）E作用表位的氨基酸序列定位为aa1-15、aa6-20、aa46-60、aa71-85和aa101-115。α-乳白蛋白IgE作用表位关键氨基酸为第8位的缬氨酸、第9位的苯丙氨酸、第10位的精氨酸、第103位的酪氨酸、第105位的亮氨酸和第107位组氨酸。本研究可以为过敏原cDNA克隆以激活T细胞、降低IgE结合能力提供重要思路。

英文摘要：

α-Lactalbumin represents one of the major allergens causing cow milk allergy.The identification of the epitopesofα-lactalbumin and the critical amino acids for its allergenicity is of great significance for understanding the mechanism ofaction ofα-lactalbumin and developing hypoallergenic dairy products.In this study,a series of peptides were synthesized bya solid phase method for the characterization of immunological epitopes and critical amino acids.The immunoglobulin(Ig)E-binding epitopes were immunolabeled with individual sera from cow milk-allergic patients as probes by enzyme linkedimmunosorbent assay(ELISA).Alanine scanning of immunodominant epitopes was used to identify the critical amino acids(aa).The results showed that IgE-binding epitopes were located within the sequences of aa1-15,aa6-20,aa46-60,aa71-85and aa101-115.Our initial data revealed that Val8,Phe9,Arg10,Tyr103,Leu105and His107were the critical amino acids forIgE-binding epitopes.This study will provide the necessary information to alter the cDNA to encode a protein capable ofactivating milk-specific T cells,but with reduced IgE-binding capacity.