Expression of VP1 protein of foot-and-mouth disease virus serotype O originated from Indonesia in mammalian cells as potential immunogen

Abstract

In 2022, Indonesia experienced foot-and-mouth disease (FMD) outbreak resulting in the death of hundreds of cattle; after more than 30 years, the country maintained FMD-free status. The FMD viral polypeptides-1 (VP1) protein contains major antigenic sites, making the protein have an important role in diagnostic applications or vaccine development. In this study, a synthetic codon-optimized vp1 gene from FMD virus serotype O was integrated into pcDNA3.1 vector and transformed to Escherichia coli TOP10F’ for plasmid propagation. The pcDNA3.1-1D-VP1 FMDV plasmid was then verified using agarose gel, showing in 659 bp size of the DNA fragment. The VP1 recombinant plasmid was transfected into HEK293T cells in DMEM medium supplemented with 10% FBS. Protein profiles were determined with SDS-PAGE showing target protein at 33KDa. Protein expression was confirmed by in-cell western assay using anti-VP1 type O polyclonal antibody and IRDye® 800CW goat anti-rabbit IgG as the secondary antibody. The result revealed a high-intensity fluorescence signal, indicating a strong interaction between expressed protein and anti-VP1 antibody. Thus, the results of this study demonstrate the potential for VP1 protein to be used as an immunogen in vaccine or diagnostic development against FMD infection. Nonetheless, some additional studies should be conducted.