Citation
- Authors: Guo J. et al.
- Year: 2022
- Journal: J Med Virol 94 3791-3800
- Applications: in vitro / DNA / FectoPRO
- Cell type: FreeStyle 293-F
Method
For antibody purification, FreeStyle™ 293-F cells were transfected with equal quantities of heavy chain and light chain expression plasmids using FectoPRO transfection reagent (Polyplus-Transfection) for complete antibody expression. Four days posttransfection, the harvested supernatants were clarified by centrifugation, filtered through a 0.22 μm filter membrane, and loaded onto a HiTrap MabSelect Xtra Column (GE Healthcare). The successfully expressed and purified antibodies were then buffer-exchanged in PBS, sterilized by filtration through a 0.22-μm filter (Millipore), and stored at a concentration of 1 mg/ml at 4°C for further research.
Abstract
The emerging coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the causative agent of coronavirus disease 2019 (COVID-19), which has become a severe threat to global public health and local economies. In this study, several single-chain antibody fragments that bind to the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein were identified and used to construct human-mouse chimeric antibodies and humanized antibodies. These antibodies exhibited strong binding to RBD and neutralization activity towards a SARS-CoV-2 pseudovirus. Moreover, these antibodies recognize different RBD epitopes and exhibit synergistic neutralizing activity. These provide candidate to combination use or bispecific antibody to potential clinical therapy for COVID-19.