Improvement in the binding specificity of anti-isomiroestrol antibodies by expression as fragments under oxidizing conditions inside the SHuffle T7 E. coli cytoplasm

• Main Author: Juengsanguanpornsuk W.
• Other Authors: Mahidol University
• Format: Article
• Published: 2023
• Subjects: Medicine
• Online Access: https://repository.li.mahidol.ac.th/handle/123456789/85496

Sensitive and specific analysis of isomiroestrol (Iso) is required for the quality control of Pueraria candollei, a herb used to treat menopausal disorders. The anti-isomiroestrol monoclonal antibody (Iso-mAb) exhibits cross-reactivity with miroestrol and deoxymiroestrol, which impacts the analytical results. Here, the active and soluble forms of the single-chain variable fragment (Iso-scFv) and fragment antigen-binding (Iso-Fab) against Iso were expressed using Escherichia coli SHuffle® T7 to alter the binding specificity. The Iso-scFv format exhibited a higher binding activity than the Iso-Fab format. The reactivity of Iso-scFv towards Iso was comparable with that of the parental Iso-mAb. Remarkably, the binding specificity of the scFv structure was improved and cross-reactivity against analogs was reduced from 13.3-21.0% to 1%. The structure of recombinant antibodies affects the binding characteristics. Therefore, the immunoassays should improve specificity; these findings can be useful in agricultural processes and for quality monitoring of P. candollei-related materials.