Timmerman Peter, Puijk Wouter C, Meloen Rob H
Pepscan Therapeutics B.V., PO Box 2098, 8203 AB Lelystad, The Netherlands.
J Mol Recognit. 2007 Sep-Oct;20(5):283-99. doi: 10.1002/jmr.846.
This paper describes immunization studies with CLIPS-constrained peptides covering only the major part (beta3-loop) of a structurally complex antigenic site on human Follicle Stimulating Hormone beta-subunit (FSH-beta). In cases where linear and SS-constrained peptides fail, the CLIPS-constrained peptides generate polyclonal antibodies with high neutralizing activity for hFSH. The sera were shown to be specific for hFSH over human Luteinizing Hormone (hLH) and human Chorionic Gonadotropin (hCG). ELISA-competition studies and circular dichroism (CD)-measurements illustrate clearly that activity of the peptides in antibody binding and generation relates directly to precise and appropriate fixation of the peptide conformation. Design of the CLIPS-peptides was entirely based on epitope mapping studies with two neutralizing anti-hFSH mAbs. Both mAbs were shown to bind to a conformational epitope located at the top of the beta1-beta3-loop covering the amino acid sequences Y58-P77 (beta3-loop). The results described in this paper show that CLIPS-constrained peptides covering the Y58-P77 sequence provide the minimally required structural entity necessary to generate reproducibly sera with high hFSH-neutralizing activity.
本文描述了针对仅覆盖人促卵泡激素β亚基（FSH-β）结构复杂抗原位点主要部分（β3环）的CLIPS约束肽的免疫研究。在线性肽和SS约束肽失效的情况下，CLIPS约束肽能产生对hFSH具有高中和活性的多克隆抗体。结果表明，这些血清对hFSH具有特异性，而对人促黄体生成素（hLH）和人绒毛膜促性腺激素（hCG）无特异性。ELISA竞争研究和圆二色性（CD）测量清楚地表明，肽在抗体结合和产生中的活性直接与肽构象的精确和适当固定有关。CLIPS肽的设计完全基于用两种中和抗hFSH单克隆抗体进行的表位作图研究。两种单克隆抗体均显示与位于β1-β3环顶部、覆盖氨基酸序列Y58-P77（β3环）的构象表位结合。本文所述结果表明，覆盖Y58-P77序列的CLIPS约束肽提供了产生具有高hFSH中和活性的可重复血清所需的最小结构实体。
