Nucleic acid-based vaccines, such as DNA vaccine, are one of the options for vaccination against the disease COVID-19. Using the Gene Electro Transfer method, we improve the poor immunogenicity of the DNA vaccine and provide better efficacy. We have produced a vaccine based on plasmid DNA. As antigens were used two plasmids that encode SARS-CoV-2 spike (S) or nucleocapsid (N) protein. Transfection of mouse fibroblast cells L929 was performed by Gene Electro Transfer. In in vitro study, we checked the expression of the antigens at the mRNA and protein levels. Using RT-qPCR, we have shown that in experimental groups S, N, and N+S, gene expression for N and S proteins occurs. Finally, antigens were determined at the protein level. N protein was detected by ELISA in the cell medium and cell lysate. In the N+S group in the cell medium, we detected a 6 times higher concentration of N protein than in the N group. In cell lysate, we were able to demonstrate a 3-fold higher concentration of N protein in the N+S experimental group compared to the N group. We were not able to detect S protein with the ELISA assay, thus, could not confirm it at the protein level. The final outcomes of the in vitro study were used by the Department of Experimental oncology, OI for in vivo studies.
|
