Application of Baculovirus Expression Vector system (BEV) for COVID-19 diagnostics and therapeutics: a review

BACKGROUND

The baculovirus expression vector system has been developed for expressing a wide range of proteins, including enzymes, glycoproteins, recombinant viruses, and vaccines. The availability of the SARS-CoV-2 genome sequence has enabled the synthesis of SARS-CoV2 proteins in a baculovirus-insect cell platform for various applications. The most cloned SARS-CoV-2 protein is the spike protein, which plays a critical role in SARS-CoV-2 infection. It is available in its whole length or as subunits like S1 or the receptor-binding domain (RBD). Non-structural proteins (Nsps), another recombinant SARS-CoV-2 protein generated by the baculovirus expression vector system (BEV), are used in the identification of new medications or the repurposing of existing therapies for the treatment of COVID-19. Non-SARS-CoV-2 proteins generated by BEV for SARS-CoV-2 diagnosis or treatment include moloney murine leukemia virus reverse transcriptase (MMLVRT), angiotensin converting enzyme 2 (ACE2), therapeutic proteins, and recombinant antibodies. The recombinant proteins were modified to boost the yield or to stabilize the protein.

CONCLUSION

This review covers the wide application of the recombinant protein produced using the baculovirus expression technology for COVID-19 research. A lot of improvements have been made to produce functional proteins with high yields. However, there is still room for improvement and there are parts of this field of research that have not been investigated yet.

Current Status of Genetically Modified Baculovirus Insecticide for Pest Control

Baculovirus is an insect specific virus which is harmless to human. This feature has made it suitable to be applied as biopesticide. It has been used to control the insect pest particularly in agriculture sector for half a century and several success stories have been shared. Nevertheless, this insecticide still cannot compete with the synthetic pesticides owing to its slow killing speed and deficiency of compatible hosts. Genetically engineered baculovirus has improved pathogenicity against insect by incorporating foreign genes. These foreign genes encode neurotoxin, hormones, enzymes, and antisense DNA. Expression of these genes can enhance the insecticidal activities of the recombinant baculovirus. Nonetheless, the genetically modified baculovirus still has not been commercialised until today. This might be associated with the concern about the release of the genetically modified organism (GMO) into the environment as the environmental impact of the genetically modified virus is not well understood. Furthermore, it has been found to have effect on certain parasitoid. In conclusion, genetic modifications of the baculovirus have successfully improved its insecticidal activities but insufficient knowledge about its safety has limited its use in the field.