Production of SARS-CoV-2 Spike RBD using the Baculovirus Expression System

POODTS JOAQUÍN; IGNACIO SMITH; BIRENBAUM, JOAQUÍN MANUEL; MARÍA SOL RODRIGUEZ; MONTERO, LUCIANO; F. WOLMAN; ALONSO LEONARDO; A. TARGOVNIK; MARIA V MIRANDA

Conferencia; ACS Fall 2023; 2023

Insect cell-baculovirus expression vector system is one of the most established platformsto produce biological products, and it plays a fundamental role in the context of COVID-19 emergency, providing recombinant proteins for treatment, diagnosis, and prevention.SARS-CoV-2 infection is mediated by the interaction of the spike glycoprotein trimer viaits receptor-binding domain (RBD) with the host's cellular receptor. As RBD is requiredfor many applications, in the context of pandemic it is important to meet the challenge ofproducing a high amount of pure recombinant RBD (rRBD). For this reason, in thepresent study, we developed a process based on Sf9 insect cells to improve rRBD yield.Expressed under a novel chimeric promoter (polh-pSeL), rRBD yield was 25.6 ± 3.0mg/L culture, which is the highest performance described in Sf9 cell lines. rRBD wasrecovered from the supernatant of infected cells and easily purified in only one step bymetal ion affinity chromatography using Nuvia IMAC Ni-NTA Resin (BioRad), with ayield of 82% and purity higher than 95%. Finally, rRBD   was successfully used in anassay to detect specific antibodies in serum samples from COVID-19 serum samples. Theefficient strategy herein described has the potential to produce high-quality rRBD in Sf9cell line for different applications.