水牛奶中β-乳球蛋白过敏原表位定位的初步研究

Primary Epitope Mapping of β-Lactoglobulin from Buffalo Milk

为绘制水牛奶中β-乳球蛋白的过敏原表位,本实验以兔抗水牛乳β-乳球蛋白的抗体IgG为固相筛选分子,免疫筛选噬菌体随机七肽库,采用间接ELISA和竞争抑制ELISA鉴定阳性克隆。经四轮富集后,得到16个阳性克隆子,进行测序,得到5个不同的肽段。与已知的表位比对,初步确定了六个IgG识别表位,分别为:第41～51位(VYVEELKPIPE)、第51～64位(EGDLEILLQKWENDE)、第81～96位(VFKIDALNE NKVLVLD)、第141～56位(KALPMHIRLSFNPTQL)、第127～136位(LNENKVLVLD)和第145～159位(MHIRLSFNPTQLEEQ)。

To map the mimotopes of β-lactoglobulin from water buffalo milk, the specific rabbit antibody against buffalo β-lactoglobulin were used to pan the specific phage from a heptapeptide phage display library. The positive clones were identified by indirect ELISA and competitive ELISA. After fourth round enrichment , sixteen positive clones were obtained and five different clones peptide sequence were deduced by DNA sequencing. Compared with the known IgG epitopes of β-lactoglobulin, six epitopes have been identified, which are located at fragment 41～51（VYVEELKPIPE）, fragment 51～64（EGDLEILLQKWENDE）, fragment81～96（VFKIDALNE NKVLVLD）, fragment 141～156（KALPMHIRLSFNPTQL）, fragment127～136 （LNENKVLVLD） and fragment 145～159（MHIRLSFNPTQLEEQ respectively.