In a years’ time the covid-19 pandemic has had an impact on research publishing. Science worldwide have put their specific expertise to contribute to a better understanding of SARS-CoV-2 genome sequence, structure, and mechanism of action to develop vaccines at unprecedented speed. While the first developed vaccines are being administered less than a year after the beginning of the pandemic, the protection that these vaccines procure may be short-lived due to the emergence of SARS-COV-2 strains that evade vaccine immunity. Therefore, research is still actively strong to develop innovative strategies or alternatively repurpose existing treatments to fight against virus infection.
jetOPTIMUS® a lab bench essential for coronavirus research
jetOPTIMUS® is a broad range DNA transfection reagent that significantly improves delivery in all adherent cell types, whether easy to transfect such as HEK-293 cells or hard to transfect cells such as primary mesenchymal stem cells. Adherent HEK-293 cells offer a great cell model to identify protein interactions that play a decisive role in viral infection. For example, Zhang et al., 2021 used jetOPTIMUS® to study intracellular protein-protein interactions between NSP1 protein of SARS-CoV-2 and the mRNA export receptor NXF1 NXT1. Alike influenza viruses, NSP1 protein may also block endogenous gene expression in favor of its own replication by targeting the mRNA nuclear export machinery. jetOPTIMUS® was used to transfect adherent HEK-293 cells with plasmid DNA encoding for different constructs of NSP1 to perform GST pulldown and co-immunoprecipitation of NXF1 NXT1 from cell lysates.
Zhang K. et al. (2021) Sci Adv 7, eabe7386. Nsp1 protein of SARS-CoV-2 disrupts the mRNA export machinery to inhibit host gene expression.
FectoPRO® for scalable production of antibody against COVID-19 and novel strategies
The coronavirus spike protein is key to virus entry into cells with its ability to bind at high affinity to the cell surface metallopreotease ACE2. Researchers are focusing on specific tertiary structures of the spike protein to develop potent treatments. To study the spike protein, the first step is recombinant protein production in mammalian cells. FectoPRO® transfection reagent is optimized for rapid and high-yield recombinant protein production in mammalian cell line and derivatives of HEK-293 and CHO cells grown in suspension. There are several derivatives of HEK-293 and CHO cell lines that have been developed to grow at higher density, and FectoPRO® can be utilized to transfect these higher cell density derivatives. Here is an example of novel strategies that could be beneficial as complementary treatments to vaccines, especially with the growing number of existing variants. In a recent preprint study, Grishin et al., 2021 used FectoPRO® to quickly produce in high cell density Expi293 cells the receptor binding domain (RBD) of the Spike protein and the corresponding domain of the ACE2 receptor. Their goal was to study whether disruption of the multiple disulfide bonds in the RBD of the SARS-COV-2 Spike protein could disrupt its function, and therefore decrease its binding affinity to the ACE2 receptor. They demonstrated that reducing agents of disulfide bonds such as DTT and TCEP could have a strong antiviral effect and prevent infection.
Grishin AM et al. (2021). bioRxiv. Spike protein disulfide disruption as a potential treatment for SARS-CoV-2