Fitriana Wahyu, Sakai Takahiro, Duan Lian, Hengphasatporn Kowit, Shigeta Yasuteru, Mashima Tsuyoshi, Uda Taizo, Hifumi Emi, Hirota Shun
Division of Materials Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.
J Med Chem. 2024 Dec 26;67(24):22313-22321. doi: 10.1021/acs.jmedchem.4c02570. Epub 2024 Dec 10.
Development of different platforms would be useful for designing functional antibodies to improve the efficiency of antibody-based drugs. Three-dimensional domain swapping (3D-DS) may occur in the variable region of antibody light chain #4C214A, and a pair of domain-swapped dimers may interact with each other to form a tetramer. In this study, to stabilize the 3D-DS dimer structure in #4C214A, Val2 in strand A (swapping region) and Thr97 in strand G were replaced with Cys residues, generating #4 V2C/T97C/C214A with a Cys2-Cys97 disulfide bond that cross-links strands A and G of different protomers. The #4 V2C/T97C/C214A tetramer did not dissociate into monomers at low protein concentration (6 μM); however, some of the tetramers were converted to monomers by disulfide bond reduction. Two-dimensional free energy profile analysis for the tetramerization of two 3D-DS dimers was performed by molecular dynamics simulation. These results show that disulfide bond introduction is useful for controlling the dimerization/dissociation of the variable region through 3D-DS.
开发不同的平台对于设计功能性抗体以提高基于抗体的药物效率将是有用的。三维结构域交换（3D-DS）可能发生在抗体轻链#4C214A的可变区，一对结构域交换二聚体可能相互作用形成四聚体。在本研究中，为了稳定#4C214A中的3D-DS二聚体结构，将链A（交换区）中的Val2和链G中的Thr97替换为半胱氨酸残基，生成具有Cys2-Cys97二硫键的#4 V2C/T97C/C214A，该二硫键交联不同原体的链A和链G。#4 V2C/T97C/C214A四聚体在低蛋白浓度（6μM）下不会解离成单体；然而，一些四聚体通过二硫键还原转化为单体。通过分子动力学模拟对两个3D-DS二聚体的四聚化进行了二维自由能分布分析。这些结果表明，引入二硫键有助于通过3D-DS控制可变区的二聚化/解离。
