Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, Beijing, People's Republic of China.
College of Food Science and Technology, Henan Agricultural University, Henan, People's Republic of China.
J Mol Recognit. 2019 Jun;32(6):e2776. doi: 10.1002/jmr.2776. Epub 2019 Jan 20.
The antigen-antibody interaction determines the sensitivity and specificity of competitive immunoassay for hapten detection. In this paper, the specificity of a monoclonal antibody against alternariol-like compounds was evaluated through indirect competitive ELISA. The results showed that the antibody had cross-reactivity with 33 compounds with the binding affinity (expressed by IC ) ranging from 9.4 ng/mL to 12.0 μg/mL. All the 33 compounds contained a common moiety and similar substituents. To understand how this common moiety and substituents affected the recognition ability of the antibody, a three-dimensional quantitative structure-activity relationship (3D-QSAR) between the antibody and the 33 alternariol-like compounds was constructed using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods. The q values of the CoMFA and CoMSIA models were 0.785 and 0.782, respectively, and the r values were 0.911 and 0.988, respectively, indicating that the models had good predictive ability. The results of 3D-QSAR showed that the most important factor affecting antibody recognition was the hydrogen bond mainly formed by the hydroxyl group of alternariol, followed by the hydrophobic force mainly formed by the methyl group. This study provides a reference for the design of new hapten and the mechanisms for antibody recognition.
抗原-抗体相互作用决定了半抗原检测竞争免疫分析的灵敏度和特异性。本文通过间接竞争 ELISA 评估了一种针对 alternariol 类似物的单克隆抗体的特异性。结果表明，该抗体与 33 种具有结合亲和力（以 IC 表示）的化合物具有交叉反应性，其范围从 9.4 ng/mL 到 12.0 μg/mL。所有 33 种化合物都含有一个共同的部分和相似的取代基。为了了解这个共同的部分和取代基如何影响抗体的识别能力，使用比较分子场分析（CoMFA）和比较分子相似性指数分析（CoMSIA）方法构建了抗体与 33 种 alternariol 类似物之间的三维定量构效关系（3D-QSAR）。CoMFA 和 CoMSIA 模型的 q 值分别为 0.785 和 0.782，r 值分别为 0.911 和 0.988，表明模型具有良好的预测能力。3D-QSAR 的结果表明，影响抗体识别的最重要因素是 alternariol 羟基主要形成的氢键，其次是甲基主要形成的疏水作用力。本研究为新半抗原的设计和抗体识别机制提供了参考。
