Construction of Porcine Epidemic Diarrhea Virus-Like Particles and Its Immunogenicity in Mice.

Jihee Kim,Jung-Eun Park,Jaewon Yoon

doi:10.3390/vaccines9040370

Abstract

Porcine epidemic diarrhea (PED), a highly contagious and lethal enteric disease in piglets, is characterized by diarrhea, vomiting, and dehydration, with high mortality in neonatal piglets. Despite the nationwide use of attenuated and inactivated vaccines, the outbreak of PED is still a major problem in the swine industry. Virus-like particles (VLPs) are artificial nanoparticles similar to viruses that are devoid of genetic material and are unable to replicate. VLPs have good safety profiles and elicit robust cellular and humoral immune responses. Here, we generated PED VLPs in eukaryotic cells and examined their immune responses in mice. We found that the M protein is essential for the formation of PED VLPs. Interestingly, PED VLP formation was decreased in the presence of E proteins and increased in the presence of N proteins. Both IgG and IgA antibodies were induced in mice immunized with PED VLPs. Moreover, these antibodies protected against PED virus infection in Vero cells. PED VLPs immunization induced Th2-dominant immune responses in mice. Our results indicate that PED VLPs induce strong immune responses in mice, suggesting that the VLP-based vaccine is a promising vaccine candidate.

Highlights

Laboratory of Veterinary Public Health, College of Veterinary Medicine, Chungnam National University, Research Institute of Veterinary Science, Chungnam National University, Daejeon 34134, Korea
M Protein Expression Is Sufficient for the Formation of Porcine epidemic diarrhea (PED) Virus-like particles (VLPs)
The PED virus (PEDV) S, E, M, and N genes were cloned into the pCAGGS vector, and the recombinant plasmid was confirmed using restriction digestion analysis as well as DNA

Summary

Introduction

PED is characterized by watery diarrhea, vomiting, anorexia, dehydration, and weight loss [2] It affects pigs of all ages, but most severely neonatal piglets, reaching morbidity and mortality of up to 100% [3]. The S protein mediates attachment of the virus to the host cell surface receptors and subsequent fusion between the viral and host cell membranes to facilitate viral entry into the host cell [12,13]. It is a key target for the host antibody response and a good candidate for a protein-based vaccine immunogen [14].

Methods

Results

Conclusion