In vitro Production and Characterization of a Recombinant Viral Protein (rVP1) of Coxsackievirus B3 (CVB3): Contribution for the Development of a Subunit Vaccine or an Immunodiagnostic Reagent

Coxsackievirus B3 is an Enterovirus implicated in diverse human pathologies, from viral myocarditis to neurological disorders. There isn’t a medicinal agent or vaccine for CVB3 in clinical use at the moment, despite the possibility that vaccination could lower the prevalence of these illnesses. This study focuses on the in vitro production and characterization of the viral protein 1 (VP1) in the objective to use it as subunit vaccine and/or immunodiagnostic reagent. VP1 is considered as the most immunogenic capsid protein of the CVB3 surface. We amplified the VP1 whole gene by RT-PCR from the extracted wild type Nancy strain RNA, then cloned it into the pUC19 plasmid expression vector, and expressed it in E. coli DH5a prokaryotic cells. The obtained recombinant proteins were then analyzed by SDS-PAGE and characterized by Bioinformatic software tools. Our results revealed that the produced recombinant amino acid VP1 (rVP1) is highly identical to the VP1 of the CVB3 wild-type strain and has very similar physicochemical properties. In addition, we demonstrated that rVP1 has the highest number of phosphorylation sites which means that rVP1 can translate the host cell signal via the phosphorylation mechanism. Moreover, The Linear B cell epitope analysis showed that the rVP1 contains many epitope regions that should be recognized by the humoral host immune response. Taken together, results demonstrate that the cloned and recombined expressed viral protein could be used to carry out any studies concerning the development a protein subunit vaccine against CVB3 infections or an immunodiagnostic reagent for detecting the virus in samples.