新型鹅细小病毒VP3病毒样颗粒的制备及免疫原性鉴定OA

Short beak and dwarfism syndrome(SBDS)in ducks could be caused by novel goose parvovirus(NGPV)that is a non-enveloped and single-stranded DNA virus.In order to prepare NGPV VP3 virus-like particles(VLPs)and evaluate their immunogenicity,VP3 gene of NGPV SD strain genome was amplified by PCR.The gene sequence was subsequently optimized(through codon preference optimization with addition of a translation-enhancing sequence at 5'end of the target gene),and a recombinant strain expressing the VP3 protein was constructed using a molecular chaperone co-expression strategy.The expressed VP3 protein was purified and emulsified for preparation of subunit vaccines.The prepared vaccine samples were inoculated into ducklings for assessment of their immune efficacy.The results showed that uniform VLPs approximately 20 nm in diameter were assembled from the purified VP3 protein,as confirmed by transmission electron microscopy.Immunogenicity analysis revealed that these VLPs exhibited high affinity with NGPV-positive serum(antigen titer 1∶512),and the prepared subunit vaccines induced high levels of neutralizing antibodies in target animals[titer:(6.20±0.65)log2].In conclusion,an efficient process for soluble expression of NGPV VP3 protein and preparation of VLPs was established,laying a foundation for further development and application of NGPV subunit vaccines.