Format

Send to

Choose Destination
J Gen Virol. 2018 Jul;99(7):897-907. doi: 10.1099/jgv.0.001081. Epub 2018 Jun 7.

Development of a Japanese encephalitis virus genotype V virus-like particle vaccine in silkworms.

Author information

1
1​The Institute of Biological Resources, Okinawa, Japan.
2
2​Laboratory of Veterinary Pathology, Department of Veterinary, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan.
3
3​Equine Research Institute, Japan Racing Association, Tochigi, Japan.
4
4​National Institute of Advanced Science and Technology (AIST), Osaka, Japan.
5
5​Division of Microbiology, Nihon University School of Medicine, Tokyo, Japan.

Abstract

To counter the spread of multiple Japanese encephalitis virus (JEV) variants harboured in alternative host species and highly neurotoxic variants with new antigenicity, such as genotype V (Muar), methods for developing more effective and low-cost vaccines against a variety of epidemic JEV strains are required. Here, we successfully synthesized large amounts of a Muar virus-like particle (MVLP) vaccine for JEV in silkworm pupae by using a Bombyx mori nuclear polyhedrosis virus recombinant consisting of JEV codon-optimized envelope (E) DNA. In particular, histopathological examination suggested that MVLP was efficiently synthesized in body fat tissues as well as epithelial cells. Quantitative analysis indicated that one silkworm pupa produced 724.8 µg of E protein in the MVLP vaccine. Electron microscopic examination of purified MVLP vaccine defined a typical MVLP morphological structure. Detailed MVLP antigen assessment by immune-electron microscopy revealed that the majority of MVLPs were covered with approximately 10 nm projections. Boosted immunization with MVLP antigens in mice and rabbits tended to show improved plaque inhibition potency against homologous Muar and heterologous Nakayama, but less potency to Beijing-1 strains. Notably, mixed immune rabbit antisera against Nakayama and Muar VLP antigens led to an increase in the low antibody reaction to Beijing-1. Additionally, a stopgap divalent JEV vaccine consisting of MVLP and Nakayama VLP and its immune mouse serum significantly increased plaque inhibition titre against Muar, Nakayama and Beijing-1 strains. These findings suggested that low-cost MVLP vaccines prepared in silkworm pupae are suitable for providing simultaneous protection of individuals in developing countries against various JEV strains.

KEYWORDS:

Japanese encephalitis genotype V virus; silkworm; vaccine; virus-like particle

PMID:
29877787
DOI:
10.1099/jgv.0.001081
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Ingenta plc
Loading ...
Support Center