Abstract: Enhancing immunogenicity and antiviral protection of inactivated porcine reproductive and respiratory syndrome virus vaccine in piglets
OBJECTIVE
Porcine interferon-γ (poIFN-γ) and porcine granulocyte-macrophage colony-stimulating factor (poGM-CSF) are multifunctional cytokines that exhibit robust antiviral activity against porcine reproductive and respiratory syndrome virus (PRRSV). In this study, the immunoadjuvant effects of recombinant poIFN-γ-poGM-CSF fusion protein in inactivated PRRSV vaccine administered to piglets were assessed.
ANIMALS
Twenty-eight 4-week-old specific pathogen-free piglets.
METHODS
The experimental piglets were divided into control, highly pathologic PRRSV, PRRSV killed virus vaccine (KV), poIFN-γ-poGM-CSF, KV + 1.0 mg poIFN-γ-poGM-CSF, KV + 2.0 mg poIFN-γ-poGM-CSF, and KV + 4.0 mg poIFN-γ-poGM-CSF groups. A recombinant poIFN-γ-linker-poGM-CSF fusion gene was constructed via splicing by overlap extension PCR and prepared using an Escherichia coli expression system, after which its adjuvant activity in the context of PRRSV KV administration was assessed.
RESULTS
This analysis revealed the successful construction of the poIFN-γ-linker-poGM-CSF fusion gene via splicing by overlap extension PCR, with recombinant poIFN-γ-linker-poGM-CSF successfully being prepared in E coli with a plasmid vector for expressing thioredoxin fusion proteins with an enterokinase site. Importantly, the coadministration of poIFN-γ-linker-poGM-CSF and PRRSV KV significantly increased neutralizing antibody titers, accelerated viral clearance, reduced clinical symptoms, and prevented highly pathogenic PRRSV infection.
CLINICAL RELEVANCE
The recombinant poIFN-γ-poGM-CSF fusion protein is a promising candidate adjuvant for use in the context of swine immunization and viral challenge.
Wang, B., Zhang, S., Liu, Y., Zhao, Y., Wang, C., Li, Y., Zuo, Y., & Fan, J. (2024). Enhancing immunogenicity and antiviral protection of inactivated porcine reproductive and respiratory syndrome virus vaccine in piglets. American Journal of Veterinary Research (published online ahead of print 2024). Retrieved Jul 23, 2024, from https://doi.org/10.2460/ajvr.24.02.0025