Attanasio R, Kennedy R C, Allan J S, Maino V C, Buck D, Kanda P
Department of Virology and Immunology, Southwest Foundation for Biomedical Research, San Antonio, TX 78284.
Mol Immunol. 1990 Jun;27(6):513-22. doi: 10.1016/0161-5890(90)90070-g.
A synthetic peptide corresponding to the third complementarity determining region (CDR) of the heavy chain (CDR3VH) of anti-Leu3a, a monoclonal anti-CD4 antibody which inhibits HIV gp120 binding to CD4, was used to elicit specific anti-peptide antibodies in rabbits. The anti-peptide antisera showed anti-idiotypic antibody (anti-Id) activity and recognized both the immunizing peptide and the intact cognate protein by ELISA. In addition, the antisera reacted with isolated heavy chains of anti-Leu3a by Western blot analysis. The lack of reactivity with a panel of monoclonal anti-CD4 antibodies suggested that the anti-peptide antisera recognize a private idiotype (Id) associated with the anti-Leu3a CDR3VH region. Further studies demonstrated the inability of the rabbit antisera to inhibit the binding of anti-Leu3a to the CD4 molecule. In addition, soluble recombinant CD4 was unable to inhibit the binding of the rabbit anti-peptide antisera to anti-Leu3a indicating that the CDR3VH region may not be involved in CD4 recognition. Anti-Id containing sera from mice, rabbits and nonhuman primates immunized with the intact anti-Leu3a molecule did not bind the CDR3VH synthetic peptide, suggesting that the corresponding region of anti-Leu3a may not represent an immunodominant idiotypic determinant in thes e species. These results suggest the potential use of synthetic peptides corresponding to immunoglobulin variable (V) region amino acid sequences in generating anti-Id reagents of a predefined specificity. In addition, V-region synthetic peptides may be useful in mapping the idiotopes recognized by an anti-Id response to the cognate molecule.
一种对应于抗Leu3a重链第三互补决定区（CDR3VH）的合成肽被用于在兔体内引发特异性抗肽抗体，抗Leu3a是一种抑制HIV gp120与CD4结合的单克隆抗CD4抗体。抗肽抗血清表现出抗独特型抗体（抗Id）活性，并且通过ELISA识别免疫肽和完整的同源蛋白。此外，通过蛋白质印迹分析，抗血清与抗Leu3a的分离重链发生反应。与一组单克隆抗CD4抗体缺乏反应性表明，抗肽抗血清识别与抗Leu3a CDR3VH区域相关的个体独特型（Id）。进一步的研究表明，兔抗血清无法抑制抗Leu3a与CD4分子的结合。此外，可溶性重组CD4无法抑制兔抗肽抗血清与抗Leu3a的结合，这表明CDR3VH区域可能不参与CD4识别。用完整的抗Leu3a分子免疫的小鼠、兔和非人类灵长类动物的含抗Id血清不与CDR3VH合成肽结合，这表明抗Leu3a的相应区域可能不代表这些物种中的免疫显性独特型决定簇。这些结果表明，对应于免疫球蛋白可变（V）区氨基酸序列的合成肽在产生具有预定义特异性的抗Id试剂方面具有潜在用途。此外，V区合成肽可能有助于将抗Id反应识别的独特型表位定位到同源分子上。
