Porcine Deltacoronavirus-like Particles Produced by a Single Recombinant Baculovirus Elicit Virus-Specific Immune Responses in Mice

Viruses. 2023 Apr 29;15(5):1095. doi: 10.3390/v15051095.

Abstract

Porcine deltacoronavirus (PDCoV) causes diarrhea and vomiting in neonatal piglets worldwide and has the potential for cross-species transmission. Therefore, virus-like particles (VLPs) are promising vaccine candidates because of their safety and strong immunogenicity. To the best of our knowledge, the present study reported for the first time the generation of PDCoV VLPs using a baculovirus expression vector system, and electron micrograph analyses revealed that PDCoV VLPs appeared as spherical particles with a diameter similar to that of the native virions. Furthermore, PDCoV VLPs effectively induced mice to produce PDCoV-specific IgG and neutralizing antibodies. In addition, VLPs could stimulate mouse splenocytes to produce high levels of cytokines IL-4 and IFN-γ. Moreover, the combination of PDCoV VLPs and Freund's adjuvant could improve the level of the immune response. Together, these data showed that PDCoV VLPs could effectively elicit humoral and cellular immunity in mice, laying a solid foundation for developing VLP-based vaccines to prevent PDCoV infections.

Keywords: baculovirus; cytokine; immune response; neutralizing antibodies; porcine deltacoronavirus; virus-like particles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Neutralizing
  • Baculoviridae / genetics
  • Coronavirus Infections* / prevention & control
  • Coronavirus Infections* / veterinary
  • Coronavirus* / genetics
  • Immunity
  • Mice
  • Swine
  • Swine Diseases*

Substances

  • Antibodies, Neutralizing

Supplementary concepts

  • Porcine coronavirus HKU15

Grants and funding

This research was funded by the National Natural Science Foundation of China (32002302, 31870917), the fund of the Scientific and Technological research project of Henan province (202102110097, 222102110260), the Key Scientific Research Projects of Higher Education Institutions in Henan Province (22A180026), and the Foundation of Nanyang Normal University (2017ZX012).