Budisavljevic M, Ronco P M, Verroust P J
INSERM U.64 Hôpital Tenon, Paris, France.
J Immunol. 1990 Sep 1;145(5):1440-9.
We have previously produced mAb against angiotensin II (AII), a phylogenetically conserved vasopressive octapeptide, and shown that they identify four distinct epitopes on the AII molecule. In addition we used internal image bearing polyclonal antiidiotypic antibodies raised against rabbit anti AII to produce mAb3. In this study we analyze the segregation of the idiotypic and paratopic repertoires of the mAb1 and mAb3. Analysis of mAb1 carried out with polyclonal Ab2 raised against the four distinct paratopes permitted classification of the mAb1 into four categories: (p+, id+) comprises antibodies with shared paratopic and idiotypic specificities: (p+, id-) is made up of antibodies that fail to express the Id defined by Ab2 raised against other antibodies pertaining to the same paratopic group; (p-, id+) includes antibodies that express cross-reactive Id on distinct paratopes; (p-, id-) refers to antibodies unrelated by their paratopes and Id mAb2 confirmed these results and showed expression of identical or closely related Id on clearly distinct paratopes. At the Ab3 level, using polyclonal Ab4, there was a higher degree of Id cross-reactivity between the two paratopes available. These data suggest that the parallel set concept may apply to the immune response to a natural peptidic Ag and its internal image. Comparison of idiotypic repertoires of mAb1 and mAb3 (using Ab2 and Ab4 antibodies) confirmed the lack of public Id and showed the predominance on mAb3 of "new" idiotypes absent from mAb1 molecules, as expected for internal image-induced antibodies. Cross-reactive idiotypes defined on mAb1 and conserved on mAb3 were expressed on the two paratopes defined at the Ab3 level. They were located on the H chain of the homologous paratope and required the association of H and L chains on the heterologous paratope. Our analysis suggests that, in the AII system, the idiotypic and paratopic repertoires segregate at least in part independently. The paratopic repertoire is limited to a small number of phylogenetically conserved specificities and may be encoded by germline genes. In contrast, the idiotypic repertoire is broader with respect to specificities, species, and localization on H and L chains. This extended diversity may be generated by somatic mutations or use of various combinations of H and L chains and/or V, D, J segments.
我们之前制备了针对血管紧张素II（AII）的单克隆抗体，AII是一种在系统发育上保守的血管收缩八肽，并且表明它们识别AII分子上的四个不同表位。此外，我们使用针对兔抗AII产生的带有内影像的多克隆抗独特型抗体来制备单克隆抗体3。在本研究中，我们分析了单克隆抗体1和单克隆抗体3的独特型和互补位库的分离情况。用针对四个不同互补位产生的多克隆抗体2对单克隆抗体1进行分析，可将单克隆抗体1分为四类：（p +，id +）包括具有共享互补位和独特型特异性的抗体；（p +，id -）由未能表达由针对属于同一互补位组的其他抗体产生的抗体2所定义的独特型的抗体组成；（p -，id +）包括在不同互补位上表达交叉反应独特型的抗体；（p -，id -）指其互补位和独特型不相关的抗体。单克隆抗体2证实了这些结果，并表明在明显不同的互补位上表达相同或密切相关的独特型。在单克隆抗体3水平，使用多克隆抗体4，两个可用互补位之间的独特型交叉反应程度更高。这些数据表明，平行集概念可能适用于对天然肽抗原及其内影像的免疫反应。对单克隆抗体1和单克隆抗体3的独特型库进行比较（使用抗体2和抗体4）证实缺乏公共独特型，并表明如内影像诱导抗体所预期的那样，单克隆抗体3上存在单克隆抗体1分子中不存在的“新”独特型占主导地位。在单克隆抗体1上定义并在单克隆抗体3上保守的交叉反应独特型在单克隆抗体3水平定义的两个互补位上表达。它们位于同源互补位的重链上，并且在异源互补位上需要重链和轻链的结合。我们的分析表明，在AII系统中，独特型和互补位库至少部分独立分离。互补位库限于少数在系统发育上保守的特异性，并且可能由种系基因编码。相比之下，独特型库在特异性、物种以及在重链和轻链上的定位方面更广泛。这种扩展的多样性可能由体细胞突变或重链和轻链以及/或V、D、J片段的各种组合的使用产生。
