Novel constructs and 1-step chromatography protocols for the production of Porcine Circovirus 2d (PCV2d) and Circovirus 3 (PCV3) subunit vaccine candidates

• Porcine Circovirus 2 vaccines are vital in preventing large-scale losses pig farms. There is a need to develop low-cost against the prevalent PCV2d strains. A vaccine candidate has been expressed at very high levels E. coli . An effective single-step chromatography protocol gives yields of over 1 g/L culture. The purified product possesses virus neutralising activity cell based assays. circovirus type (PCV2) major problem for production industry worldwide decades. While majority commercially available on original PCV2a genotype, current dominant genotype PCV2d. notable differences between genotypes could lead incomplete cross-protection. Moreover, most subunit PCV2 generated from expensive insect culture technology. In this work, we present new workflow an updated and relatively inexpensive candidate. After expression fed-batch Escherichia fermentation systems with simple one-step ion-exchange purification protocol, yield PCV2d-based antigen reached g per litre bacterial Using similar procedures, also demonstrated even higher chimeric PCV2d-PCV3 capsid construct, which cleaved during release PCV2d- PCV3-related polypeptides. Although recombinant protein did not form viral-like particles as analysed by size-exclusion chromatography, it effectively induce capsid-specific PCV2d-neutralising antibodies immunised animals, indicating significant potential that can be easily manufactured commercial scale.