Zhang Tao, Nagel-Steger Luitgard, Willbold Dieter
Institute of Complex Systems, Structural Biochemistry (ICS-6) Forschungszentrum Jülich 52425 Jülich Germany.
Institut für Physikalische Biologie Heinrich-Heine-Universität Düsseldorf 40225 Düsseldorf Germany.
ChemistryOpen. 2019 Jul 22;8(7):989-994. doi: 10.1002/open.201900167. eCollection 2019 Jul.
Amyloid β-peptides (Aβ) play a major role in the pathogenesis of Alzheimer's disease. Therefore, numerous monoclonal antibodies against Aβ have been developed for basic and clinical research. The present study applied fluorescence based analytical ultracentrifugation and microscale thermophoresis to characterize the interaction between Aβ42 monomers and three popular, commercially available antibodies, namely 6E10, 4G8 and 12F4. Both methods allowed us to analyze the interactions at low nanomolar concentrations of analytes close to their dissociation constants ( ) as required for the study of high affinity interactions. Furthermore, the low concentrations minimized the unwanted self-aggregation of Aβ. Our study demonstrates that all three antibodies bind to Aβ42 monomers with comparable affinities in the low nanomolar range. values for Aβ42 binding to 6E10 and 4G8 are in good agreement with formerly reported values from SPR studies, while the for 12F4 binding to Aβ42 monomer is reported for the first time.
淀粉样β肽（Aβ）在阿尔茨海默病的发病机制中起主要作用。因此，已开发出多种针对Aβ的单克隆抗体用于基础和临床研究。本研究应用基于荧光的分析超速离心和微量热泳技术来表征Aβ42单体与三种常用的市售抗体（即6E10、4G8和12F4）之间的相互作用。这两种方法都使我们能够在接近其解离常数（）的低纳摩尔浓度分析物下分析相互作用，这是研究高亲和力相互作用所必需的。此外，低浓度可将Aβ不必要的自聚集降至最低。我们的研究表明，所有三种抗体均以低纳摩尔范围内相当的亲和力与Aβ42单体结合。Aβ42与6E10和4G8结合的 值与先前SPR研究报告的值高度一致，而12F4与Aβ42单体结合的 值则是首次报道。
