新型抗ige人源化单克隆抗体的结构与功能分析-structural and functional analysis of a novel humanized monoclonal antibody against ige.docx

第二军医大学博士学位论文第二军医大学博士学位论文-- PAGE 4 -Hu7A5m18 epitope identified in this study. The Hu7A5m18 epitope is spatially close to the FcεRI-binding site, which explains why Hu7A5m18 can inhibit free IgE molecules to bind to receptors without affecting IgE already bound to cellular receptors. Moreover, because Hu7A5m18 and Omalizumab epitope are also spatially close, Hu7A5m18 could compete with Omalizumab in binding to human IgE.Conclusion: The present study shows that a new anti-IgE humanized anibody, Hu7A5m18, tightly binds to free circulating IgE molecules and prevents binding of these molecules to receptors. Our results provide first evidence that in IgE-sensitized cells the mAb Hu7A5m18 efficiently and dose-dependently inhibits anti-IgE-triggered degranulation. The 391KQR393 motif within the Cε3 domain of IgE-Fc was identified as the 7A5 epitope in the present study and found to be spatially close to the FcεRI-binding site, suggesting that 7A5 binding to IgE might block IgE binding to receptors via steric hindrance. Taken together, the anti-IgE monoclonal antibody7A5 may have the potential to be developed as a therapeutic agent for the treatment of allergic diseases.KEY WORDS: IgE, monoclonal antibody, epitope, phage display peptide library新型抗 IgE 人源化单克隆抗体的结构与功能研究缩略词表英文缩写 英文全称 中文全称BSA bovine serum albumin 牛血清白蛋白CDR complementary determinant region 互补决定区CHO Chinese hamster ovary 中国仓鼠卵巢细胞DAB diaminobenzidine 二甲基联苯胺EC Effective concentration 有效浓度ECL enhanced chemiluminescence 增强化学发光oli Escherichia coli 大肠杆菌ELISA enzyme linked immunosorbent assay 酶标记免疫吸附测定法FCS fetal calf serum 胎牛血清FDA Food and drug administration 食品药品监督管理局FITC fluoresceinisothiocyanate 异硫氰酸荧光素FR Frame region 框架区GSP Gene Specific Primer 基因特异性引物HAMA Human anti mouse antibody 人抗鼠抗体次黄嘌呤氨基蝶呤胸腺嘧啶HAT Hypoxantin aminopterin thymidin脱氧核苷HRP horseradish peroxidase 辣根过氧化物酶HT Hypoxantin thymidin 次黄嘌呤胸腺嘧啶脱氧核苷kDa kilodaltons 千道尔顿NC nitrocellulose 硝酸纤维素OD optical density 光密度PAGE polyacrylam