Magnusson C G, Aalberse R C, Johansson S G
Int Arch Allergy Appl Immunol. 1986;80(3):329-32.
The specificity of five monoclonal anti-IgE antibodies (Mabs) was studied in direct latex agglutination and agglutination-inhibition experiments by particle-counting immunoassay. Twenty IgE myeloma proteins and several purified D epsilon O-, D epsilon 2-containing pepsin and papain fragments of IgE-DES(kappa) were used in the evaluation. The results demonstrate two Mabs with isotypic specificity for two distinct epitopes of the Fc epsilon-fragment within the D epsilon 1- and D epsilon 2-determinants. One Mab recognized only the immunizing IgE protein and was directed against determinants on the Fd epsilon-fragment probably related to the idiotype. Anti-Em(1) allotypic Mabs recognized all 20 IgE myeloma proteins including two of Japanese origin and the Em(1)-allotype was confined to D epsilon-determinants. Interestingly, one Mab (ALE) reacted with all 8 IgE myeloma proteins of the lambda light-chain type but none out of 12 bearing kappa chains. ALE seems therefore to recognize a new marker on IgE besides the known idiotypic, allotypic and isotypic ones. These results illustrate that a critical specificity control of Mabs is always warranted. Moreover, one should be aware of possible interference in IgE assays from the kind of determinants recognized by ALE whenever intact IgE myeloma proteins are used to raise polyclonal antisera, to get immunosorbent-purified anti-IgE antibodies or when used as tracers and standards.
通过颗粒计数免疫测定法，在直接乳胶凝集和凝集抑制实验中研究了五种单克隆抗IgE抗体（Mab）的特异性。在评估中使用了20种IgE骨髓瘤蛋白以及几种纯化的IgE-DES（κ）的含DεO-、Dε2的胃蛋白酶和木瓜蛋白酶片段。结果表明，两种Mab对Dε1和Dε2决定簇内Fcε片段的两个不同表位具有同种型特异性。一种Mab仅识别免疫原性IgE蛋白，并且针对可能与独特型相关的Fcε片段上的决定簇。抗Em（1）同种异型Mab识别所有20种IgE骨髓瘤蛋白，包括两种日本来源的蛋白，并且Em（1）同种异型局限于Dε决定簇。有趣的是，一种Mab（ALE）与所有8种λ轻链型IgE骨髓瘤蛋白反应，但与12种κ链型蛋白均无反应。因此，ALE似乎除了识别已知的独特型、同种异型和同种型标记外，还识别IgE上的一种新标记。这些结果表明，始终需要对Mab进行严格的特异性控制。此外，每当使用完整的IgE骨髓瘤蛋白来制备多克隆抗血清、获得免疫吸附纯化的抗IgE抗体或用作示踪剂和标准品时，人们应该意识到ALE识别的决定簇类型可能会对IgE测定产生干扰。
