Orlandi R, Ménard S, Colnaghi M I, Boyer C M, Felici F
Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
Eur J Immunol. 1994 Nov;24(11):2868-73. doi: 10.1002/eji.1830241143.
To recover peptides that antigenically and immunogenically mimic the p185HER2 oncoprotein, we selected the phage-peptide libraries pVIII-9aa and pVIII-9aa. Cys using murine monoclonal antibodies (mAb) MGr2 and MGr6, directed against two distinct epitopes of the p185HER2 extracellular domain. Phage-displayed peptides containing consensus amino acid motifs were recovered and shown to compete specifically for mAb binding on tumor cells that overexpress p185HER2. The deduced amino acid sequence of the peptides suggests that both epitopes defined by the mAb on p185HER2 are discontinuous and that hydrophobic interactions are involved in binding with the mAb. A phage clone displaying the GPLDSLFAQ peptide elicited a specific immune response against the p185HER2 in BALB/c mice, demonstrating that this phage-displayed peptide represents an immunological equivalent of the MGr2 epitope on p185HER2 and might be used as a substitute for this oncoprotein in in vitro and in vivo immunological studies.
为了获得在抗原性和免疫原性上模拟p185HER2癌蛋白的肽段，我们使用针对p185HER2细胞外结构域两个不同表位的鼠单克隆抗体（mAb）MGr2和MGr6，筛选噬菌体肽库pVIII-9aa和pVIII-9aa.Cys。回收了含有共有氨基酸基序的噬菌体展示肽，并证明它们能在过表达p185HER2的肿瘤细胞上特异性竞争mAb结合。肽段的推导氨基酸序列表明，mAb在p185HER2上定义的两个表位都是不连续的，并且疏水相互作用参与了与mAb的结合。展示GPLDSLFAQ肽的噬菌体克隆在BALB/c小鼠中引发了针对p185HER2的特异性免疫反应，表明这种噬菌体展示肽代表了p185HER2上MGr2表位在免疫学上的等效物，可在体外和体内免疫学研究中用作该癌蛋白的替代物。
